Artificial Immune Detection for Network Intrusion Data Based on Quantitative Matching Method

Artificial immune detection can be used to detect network intrusions in an adaptive approach and proper matching methods can improve the accuracy of immune detection methods.This paper proposes an artificial immune detection model for network intrusion data based on a quantitative matching method.The proposed model defines the detection process by using network data and decimal values to express features and artificial immune mechanisms are simulated to define immune elements.Then,to improve the accuracy of similarity calculation,a quantitative matching method is proposed.The model uses mathematical methods to train and evolve immune elements,increasing the diversity of immune recognition and allowing for the successful detection of unknown intrusions.The proposed model’s objective is to accurately identify known intrusions and expand the identification of unknown intrusions through signature detection and immune detection,overcoming the disadvantages of traditional methods.The experiment results show that the proposed model can detect intrusions effectively.It has a detection rate of more than 99.6%on average and a false alarm rate of 0.0264%.It outperforms existing immune intrusion detection methods in terms of comprehensive detection performance.

Efficacy-cost analysis of endoscopic mucosal resection and cold snare polypectomy:A propensity score matching analysis

BACKGROUND Although substantial evidence supports the advantages of cold snare polypectomy(CSP)in terms of polypectomy efficacy and reduced postoperative adverse events,few studies have examined the cost differences between CSP and traditional endoscopic mucosal resection(EMR)for the treatment of intestinal polyps.AIM To compare the efficacy-cost of EMR and CSP in the treatment of intestinal polyps.METHODS A total of 100 patients with intestinal polyps were included in the retrospective data of our hospital from April 2022 to May 2023.According to the treatment methods,they were divided into EMR(n=46)group and CSP(n=54)group.The baseline data of the two groups were balanced by 1:1 propensity score matching(PSM),and the cost-effectiveness analysis was performed on the two groups after matching.The recurrence rate of the two groups of patients was followed up for 1 year,and they were divided into recurrence group and non-recurrence group according to whether they recurred.Multivariate logistic regression analysis was used to screen out the influencing factors affecting the recurrence of intestinal polyps after endoscopic resection.RESULTS Significant disparities were observed in the number of polyps and smoking background between the two groups before PSM(P<0.05).Following PSM,the number of polyps and smoking history were well balanced between the EMR and CSP groups.The direct cost incurred by the CSP group was markedly higher than that incurred by the EMR group.Concurrently,the cost-effectiveness ratio in the CSP group was substantially reduced when juxtaposed with that in the EMR group(P<0.05).Upon completion of the 1-year follow-up,the rate of recurrence after endoscopic intestinal polypectomy was 38.00%.Multivariate methods revealed that age≥60 years,male sex,number of polyps≥3,and pathological type of adenoma were risk factors for recurrence after endoscopic intestinal polypectomy(all P<0.05).CONCLUSION CSP was more cost-effective for the treatment of intestinal polyps.An age≥60 years,male sex,having a number of polyps≥3,and pathological type of adenoma are independent influencing factors for recurrence.

A New Method to Calculate the Degree of Electromagnetic Impedance Matching in One-Layer Microwave Absorbers

A delta-function method is proposed to quantitatively evaluate the electromagnetic impedance matching degree.Measured electromagnetic parameters ofα-Fe/Fe_(3)B/Y_(2)O_(3)nanocomposites are applied to calculate the matching degree by the method.Compared with reflection loss and quarter-wave principle theory,the method accurately reveals the intrinsic mechanism of microwave transmission and reflection properties.A possible honeycomb structure with promising high-performance microwave absorption,devised according to the method,is also proposed.

Stiffness-damping matching method of an ECAS system based on LQG control

A novel method of matching stiffness and continuous variable damping of an ECAS(electronically controlled air suspension) based on LQG(linear quadratic Gaussian) control was proposed to simultaneously improve the road-friendliness and ride comfort of a two-axle school bus.Taking account of the suspension nonlinearities and target-height-dependent variation in suspension characteristics,a stiffness model of the ECAS mounted on the drive axle of the bus was developed based on thermodynamics and the key parameters were obtained through field tests.By determining the proper range of the target height for the ECAS of the fully-loaded bus based on the design requirements of vehicle body bounce frequency,the control algorithm of the target suspension height(i.e.,stiffness) was derived according to driving speed and road roughness.Taking account of the nonlinearities of a continuous variable semi-active damper,the damping force was obtained through the subtraction of the air spring force from the optimum integrated suspension force,which was calculated based on LQG control.Finally,a GA(genetic algorithm)-based matching method between stepped variable damping and stiffness was employed as a benchmark to evaluate the effectiveness of the LQG-based matching method.Simulation results indicate that compared with the GA-based matching method,both dynamic tire force and vehicle body vertical acceleration responses are markedly reduced around the vehicle body bounce frequency employing the LQG-based matching method,with peak values of the dynamic tire force PSD(power spectral density) decreased by 73.6%,60.8% and 71.9% in the three cases,and corresponding reduction are 71.3%,59.4% and 68.2% for the vehicle body vertical acceleration.A strong robustness to variation of driving speed and road roughness is also observed for the LQG-based matching method.

AUTOMATIC DISPLACEMENT ANALYSIS OF PLANAR MECHANISMS WITH MATCHING BASIC KINEMATIC CHAINS METHOD

A simple, efficient, automatic and universal method to fulfill displacementanalysis of a great deal of mechanisms regenerated by Yan's mechanism creative theory has beendeveloped. For a regenerated mechanism, at first, the method identifies its type and structure andchanges it into a rigid structure by fixing the ground link and the input link. And then this rigidstructure is decomposed into a set of basic kinematic chains (BKCs). By matching the type of BKC,the displacement analysis equations can be set up, and all possible configurations, in whichpositions of all movable links are considered, can be given out.

SERIES PERTURBATIONS APPROXIMATE SOLUTIONS TO N-S EQUATIONS AND MODIFICATION TO ASYMPTOTIC EXPANSION MATCHED METHOD

A method that series perturbations approximate solutions to N-S equations with boundary conditions was discussed and adopted. Then the method was proved in which the asymptotic solutions of viscous fluid flow past a sphere were deducted. By the ameliorative asymptotic expansion matched method, the matched functions, are determined easily and the ameliorative curve of drag coefficient is coincident well with measured data in the case that Reynolds number is less than or equal to 40 000.

A bottom-up method for module-based product platform development through mapping,clustering and matching analysis

Designing product platform could be an effective and efficient solution for manufacturing firms. Product platforms enable firms to provide increased product variety for the marketplace with as little variety between products as possible. Developed consumer products and modules within a firm can further be investigated to find out the possibility of product platform creation. A bottom-up method is proposed for module-based product platform through mapping, clustering and matching analysis. The framework and the parametric model of the method are presented, which consist of three steps:(1) mapping parameters from existing product families to functional modules,(2) clustering the modules within existing module families based on their parameters so as to generate module clusters, and selecting the satisfactory module clusters based on commonality, and(3) matching the parameters of the module clusters to the functional modules in order to capture platform elements. In addition, the parameter matching criterion and mismatching treatment are put forward to ensure the effectiveness of the platform process, while standardization and serialization of the platform element are presented. A design case of the belt conveyor is studied to demonstrate the feasibility of the proposed method.

An integrated method for matching forest machinery and a weight-value adjustment

Proper matching of forestry machinery is important when raising mechanization levels for forestry production. In the matching process, forestry machinery needs not only expertise, but also improved methods for solving problems. I propose combination of case-based reasoning （CBR） and rule-based reasoning （RBR） by calculating the similarity of quantitative parameters of various forestry machines in an analytical and hierarchical process. I calculated the similarity of machin-ery used in forest industries to enable better selection and matching of equipment. I propose a weight-value adjusting method based on sums of squares of deviations in which the individual parameter weights were modified in the process of application. During the process of system design, I put forward a design method knowledge base and generated a dynamic web reasoning framework to integrate the processes of forest industry machinery selection and weight-value adjustment. This enables expansion of the scope of the complete system and enhancement of the reasoning efficiency. I demonstrate the validity and practicability of this method using a practical example.

REQUIREMENTS AND DESIGN METHOD FOR MATCHING AIRCRAFT GUNS WITH THEIR SUPPORTING STRUCTURE

In aircraft structural dynamic design the matching of guns with their supporting structure is one of the most important tasks on which hinges the success or failure of the structural design. The design curves for matching guns with their supporting structure can be obtained from response calculations of the plate-spring system supporting the gun on the ground,the model structure tested on the ground and the actual structure.A set of matching curves is given for engineering application.Then,the matching design can be accomplished by means of impact load spectrograms so as to perform an optimal structural design and to make further improvements on dynamic design program.

A Visual Indoor Localization Method Based on Efficient Image Retrieval

The task of indoor visual localization, utilizing camera visual information for user pose calculation, was a core component of Augmented Reality (AR) and Simultaneous Localization and Mapping (SLAM). Existing indoor localization technologies generally used scene-specific 3D representations or were trained on specific datasets, making it challenging to balance accuracy and cost when applied to new scenes. Addressing this issue, this paper proposed a universal indoor visual localization method based on efficient image retrieval. Initially, a Multi-Layer Perceptron (MLP) was employed to aggregate features from intermediate layers of a convolutional neural network, obtaining a global representation of the image. This approach ensured accurate and rapid retrieval of reference images. Subsequently, a new mechanism using Random Sample Consensus (RANSAC) was designed to resolve relative pose ambiguity caused by the essential matrix decomposition based on the five-point method. Finally, the absolute pose of the queried user image was computed, thereby achieving indoor user pose estimation. The proposed indoor localization method was characterized by its simplicity, flexibility, and excellent cross-scene generalization. Experimental results demonstrated a positioning error of 0.09 m and 2.14° on the 7Scenes dataset, and 0.15 m and 6.37° on the 12Scenes dataset. These results convincingly illustrated the outstanding performance of the proposed indoor localization method.

专精特新企业新产品开发绩效的组态效应研究——基于“能力-行为”匹配视角

专精特新企业对解决我国关键核心技术“卡脖子”问题具有重要意义,现有研究主要集中于创新机制和政策培育两方面,而新产品开发绩效作为专精特新企业可持续发展的重要途径,鲜有学者关注。为弥补现有研究不足,本文遵循“能力-行为”匹配视角,将数字化能力与服务化导向纳入同一研究框架,构建影响专精特新企业新产品开发绩效的组态效应模型。运用fsQCA方法对48家专精特新企业进行实证检验,检验结果表明:(1)数字化能力和服务化导向之间存在“多重并发”效应,可以通过4种不同的组合路径实现高新产品开发绩效;(2)将4种高新产品开发绩效组合路径进一步聚类,可归结为强数字化资源协调能力的能力拉动型和强产品导向服务化的服务推动型,这两种类型下数字化感知能力与客户导向服务化均具有替代效应。本文从“能力-行为”匹配视角丰富新产品开发绩效的前因组态,并为专精特新企业提升新产品开发绩效提供实践建议。

自激式电感耦合等离子体光源设计及光谱分析

电感耦合等离子体(ICP)光谱仪是一种应用范围很广的元素分析仪,主要用于元素定性与定量的分析。ICP光源是光谱仪的核心部件,它在光谱仪中扮演着至关重要的角色。目前主流的ICP光源有两种:自激式和他激式,各自具有优缺点。他激式光源电路复杂、体积庞大、阻抗匹配速度较慢、最大输出功率有限。设计了一种基于镀金工艺的高功率MOSFET和变频实现阻抗匹配的自激式ICP光源,该光源采用射频放大和阻抗匹配一体化的设计,把从负载线圈采样的频率信号f_(1)以及功率放大电路放大后的频率相位f_(0)进行相位比较,再根据两者相位差的变化,进而控制频率的变化,实现阻抗匹配;设计上采用了镀金工艺的金属化硅N通道型高功率的MOSFET实现功率放大,具有更大的功率密度、更小的体积,最大输出功率超过2400 W。对研制的ICP光源进行了电学静态测试,给出了鉴相器、压控振荡器以及功率的输出特性,验证了各电路在相应工作状态下的性能表现;同时结合光谱仪进行了包含Ba、Na和Li元素标准溶液的测试,获得了目标元素的光谱信号;另外,对获得的光谱信号进行了处理,使用了基于EEMD特征增强的方法对目标元素光谱信号进行有效增强,信号的线性决定系数(R^(2))从0.97降至0.99,相对标准偏差(RSD)从6.47%降至1.07%,增强了信号的准确性和可用性。本文所研制的自激式ICP光源,通过射频放大和阻抗匹配一体化设计缩小了体积,变频技术使阻抗匹配速度从毫秒级提升到纳秒级,镀金工艺的MOSFET技术使最大输出功率从原来的1800 W增加到2400 W,为ICP光源的进一步优化和应用奠定了基础,具有重要的科学研究和工程实践意义。

A weak formulation of heterogenous viscoacoustic wave propagation in infinite domain

The accurate simulation of wave propagation in real media requires properly taking the attenuation into account,which leads to wave dissipation together with its causal companion,wave dispersion.In this study,to obtain a weak formulation of heterogenous viscoacoustic wave propagation in an infinite domain,the viscoacoustic medium is first characterized by its frequency-dependent complex bulk compliance instead of the classically used complex bulk modulus.Then,a mechanical model using serially connected standard linear solids(SSLS)is built to obtain the rational approximation of the complex bulk compliance whose parameters are calculated via an adapted nonlinear optimization method.Utilizing the obtained bulk compliance-based constitutive relation,a novel second-order viscoacoustic wave equation in the frequency domain is derived,of which the weak formulation can be physically explained as the virtual work equation and can thus be discretized using a continuous spectral element method in space.Additionally,a new method is introduced to address the convolution terms involved in the inverse Fourier transform,whose accurate time integration can then be achieved using an explicit time scheme,which avoids the transient growth that exists in the classical method.The resulting full time-space decoupling scheme can handle wave propagation in arbitrary heterogeneous media.Moreover,to treat the wave propagation in an infinite domain,a perfectly matched layer in weak formulation is derived for the truncation of the infinite domain via complex coordinate stretching of the virtual work equation.With only minor modification,the resulting perfectly matched layer can be implemented using the same time scheme as for the wave equation inside the truncated domain.The accuracy,numerical stability,and versatility of the new proposed scheme are demonstrated with numerical examples.

急性脑梗死并发血管性痴呆的影响因素分析:基于倾向性 评分匹配法

目的基于倾向性评分匹配法探讨急性脑梗死并发血管性痴呆(VD)的影响因素。方法回顾性分析2021年1月-2023年1月到本院就诊的205例急性脑梗死患者的临床资料,随访3个月,按是否并发VD分为VD组(n=44)和非VD组(n=161)两组。比较两组一般资料,基于倾向性评分匹配两组资料,比较匹配后VD组(n=42)、非VD组(n=42)的一般资料;COX回归分析影响急性脑梗死后VD发生的相关因素。结果VD发生率为21.46%;匹配后VD组年龄大于非VD组,合并高脂血症占比、脑白质病变评分高于非VD组(P<0.05),脑梗死面积大于非VD组,脑梗死发作至入院时间长于非VD组(P<0.05);年龄(HR=1.042,95%CI:1.010~1.075,P=0.003)、高脂血症(HR=1.040,95%CI:1.004~1.077,P=0.025)、脑白质病变评分(HR=1.153,95%CI:1.055~1.259,P<0.001)、脑梗死面积(HR=1.099,95%CI:1.034~1.167,P<0.001)与脑梗死发作至入院时间(HR=1.067,95%CI:1.008~1.130,P=0.007)均为VD发生的影响因素。结论基于倾向性评分匹配发现高龄、脑梗死面积大、脑白质病变评分高、高脂血症以及脑梗死发作至入院时间长为急性脑梗死并发VD的危险因素。

电感耦合等离子体原子发射光谱法测定锆镍合金粉中锆

建立电感耦合等离子体原子发射光谱法测定锆镍合金粉中的锆含量。采用硝酸-氢氟酸溶解样品,选择339.198 nm谱线作为锆元素分析谱线,通过基体匹配法消除镍基体干扰。锆的质量分数在0.1%~40%范围内与光谱发射强度线性关系良好,相关系数为0.9997,方法检出限为0.0054%,定量限为0.018%。采用所建方法对锆镍合金模拟样品和锆镍合金粉样品进行测定,测定结果的相对标准偏差为0.208%~0.408%(n=11),样品加标回收率为98.9%~102.5%。该方法能够快速、准确地测定锆镍合金粉中的锆含量。

A strength reduction method based on double reduction parameters and its application

In the traditional strength reduction method,the cohesion and the friction angle adopt the same reduction parameter,resulting in equivalent proportional reduction.This method does not consider the different effects of the cohesion and friction angle on the stability of the same slope and is defective to some extent.Regarding this defect,a strength reduction method based on double reduction parameters,which adopts different reduction parameters,is proposed.The core of the double-parameter reduction method is the matching reduction principle of the slope with different angles.This principle is represented by the ratio of the reduction parameter of the cohesion to that of the friction angle,described as η.With the increase in the slopeangle,ηincreases; in particular,when the slope angle is 45°,tηis 1.0.Through the matching reduction principle,different safety margin factors can be calculated for the cohesion and friction angle.In combination with these two safety margin factors,a formula for calculating the overall safety factor of the slope is proposed,reflecting the different contributions of the cohesion and friction angle to the slope stability.Finally,it is shown that the strength reduction method based on double reduction parameters acquires a larger safety factor than the classic limit equilibrium method,but the calculation results are very close to those obtained by the limit equilibrium method.

Borehole-GPR numerical simulation of full wave field based on convolutional perfect matched layer boundary

The absorbing boundary is the key in numerical simulation of borehole radar.Perfect match layer(PML) was chosen as the absorbing boundary in numerical simulation of GPR.But CPML(convolutional perfect match layer) approach that we have chosen has the advantage of being media independent.Beginning with the Maxwell equations in a two-dimensional structure,numerical formulas of finite-difference time-domain(FDTD) method with CPML boundary condition for transverse electric(TE) or transverse magnetic(TM) wave are presented in details.Also,there are three models for borehole-GPR simulation.By analyzing the simulation results,the features of targets in GPR are obtained,which can provide a better interpretation of real radar data.The results show that CPML is well suited for the simulation of borehole-GPR.

Geological adaptability matching design of disc cutter using multicriteria decision making approaches

Geological adaptability matching design of a disc cutter is the prerequisite of cutter head design for tunnel boring machines(TBMs)and plays an important role in improving the tunneling efficiency of TBMs.The main purpose of the cutter matching design is to evaluate the cutter performance and select the appropriate cutter size.In this paper,a novel evaluation method based on multicriteria decision making(MCDM)techniques was developed to help TBM designers in the process of determining the cutter size.The analytic hierarchy process(AHP)and matter element analysis were applied to obtaining the weights of the cutter evaluation criteria,and the fuzzy comprehensive evaluation and technique for order performance by similarity to ideal solution(TOPSIS)approaches were employed to determine the ranking of the cutters.A case application was offered to illustrate and validate the proposed method.The results of the project case demonstrate that this method is reasonable and feasible for disc cutter size selection in cutter head design.

Thermoelastic Analysis of Non-uniform Pressurized Functionally Graded Cylinder with Variable Thickness Using First Order Shear Deformation Theory(FSDT) and Perturbation Method

Recently application of functionally graded materials（FGMs） have attracted a great deal of interest. These materials are composed of various materials with different micro-structures which can vary spatially in FGMs. Such composites with varying thickness and non-uniform pressure can be used in the aerospace engineering. Therefore, analysis of such composite is of high importance in engineering problems. Thermoelastic analysis of functionally graded cylinder with variable thickness under non-uniform pressure is considered. First order shear deformation theory and total potential energy approach is applied to obtain the governing equations of non-homogeneous cylinder. Considering the inner and outer solutions, perturbation series are applied to solve the governing equations. Outer solution for out of boundaries and more sensitive variable in inner solution at the boundaries are considered. Combining of inner and outer solution for near and far points from boundaries leads to high accurate displacement field distribution. The main aim of this paper is to show the capability of matched asymptotic solution for different non-homogeneous cylinders with different shapes and different non-uniform pressures. The results can be used to design the optimum thickness of the cylinder and also some properties such as high temperature residence by applying non-homogeneous material.

Seismic wave modeling in viscoelastic VTI media using spectral element method

Spectral element method（SEM） for elastic media is well known for its great flexibility and high accuracy in solving problems with complex geometries.It is an advanced choice for wave simulations.Due to anelasticity of earth media,SEM for elastic media is no longer appropriate.On fundamental of the second-order elastic SEM,this work takes the viscoelastic wave equations and the vertical transversely isotropic（VTI） media into consideration,and establishes the second-order SEM for wave modeling in viscoelastic VTI media.The second-order perfectly matched layer for viscoelastic VTI media is also introduced.The problem of handling the overlapped absorbed corners is solved.A comparison with the analytical solution in a twodimensional viscoelastic homogeneous medium shows that the method is accurate in the wave-field modeling.Furtherly,numerical validation also presents its great flexibility in solving wave propagation problems in complex heterogeneous media.This second-order SEM with perfectly matched layer for viscoelastic VTI media can be easily applied in wave modeling in a limited region.