Software Coupling and Cohesion Model for Measuring the Quality of Software Components

Measuring software quality requires software engineers to understand the system’s quality attributes and their measurements.The quality attribute is a qualitative property;however,the quantitative feature is needed for software measurement,which is not considered during the development of most software systems.Many research studies have investigated different approaches for measuring software quality,but with no practical approaches to quantify and measure quality attributes.This paper proposes a software quality measurement model,based on a software interconnection model,to measure the quality of software components and the overall quality of the software system.Unlike most of the existing approaches,the proposed approach can be applied at the early stages of software development,to different architectural design models,and at different levels of system decomposition.This article introduces a software measurement model that uses a heuristic normalization of the software’s internal quality attributes,i.e.,coupling and cohesion,for software quality measurement.In this model,the quality of a software component is measured based on its internal strength and the coupling it exhibits with other component(s).The proposed model has been experimented with nine software engineering teams that have agreed to participate in the experiment during the development of their different software systems.The experiments have shown that coupling reduces the internal strength of the coupled components by the amount of coupling they exhibit,which degrades their quality and the overall quality of the software system.The introduced model can help in understanding the quality of software design.In addition,it identifies the locations in software design that exhibit unnecessary couplings that degrade the quality of the software systems,which can be eliminated.

A Component Selection Framework of Cohesion and Coupling Metrics

Component-based software engineering is concerned with the develop-ment of software that can satisfy the customer prerequisites through reuse or inde-pendent development.Coupling and cohesion measurements are primarily used to analyse the better software design quality,increase the reliability and reduced system software complexity.The complexity measurement of cohesion and coupling component to analyze the relationship between the component module.In this paper,proposed the component selection framework of Hexa-oval optimization algorithm for selecting the suitable components from the repository.It measures the interface density modules of coupling and cohesion in a modular software sys-tem.This cohesion measurement has been taken into two parameters for analyz-ing the result of complexity,with the help of low cohesion and high cohesion.In coupling measures between the component of inside parameters and outside parameters.Thefinal process of coupling and cohesion,the measured values were used for the average calculation of components parameter.This paper measures the complexity of direct and indirect interaction among the component as well as the proposed algorithm selecting the optimal component for the repository.The better result is observed for high cohesion and low coupling in compo-nent-based software engineering.

Effect of Family Cohesion on Depression of Chinese College Students in the COVID-19 Pandemic: Chain Mediation Effect of Perceived Social Support and Intentional Self-Regulation

Individuals’perceptions,attitudes,and patterns of getting along with family members are important factors influencing Chinese people’s self-evaluation.The aim of this study was to investigate the effect of family cohesion on depression and the role of perceived social support and intentional self-regulation in this association.A hypothesized model of the association of family cohesion,perceived social support,intentional self-regulation,and depression was examined.A convenience sampling method was used to survey 1,180 college students in Yunnan Province using self-report.Data were collected using the Family Cohesion Scale,the Perceived Social Support Scale,the Intentional Self-Regulation Scale,and the Center for Epidemiological Studies Depression Scale.The findings revealed low to moderate correlation between the variables studied.College students’family cohesion was a negative predictor of their depression.This association was also mediated by the knock-on effect of perceived social support and intentional self-regulation.These findings show how family cohesion affects college students’depressive status.Specifically,these results help demonstrate the importance of family cohesion,perceived social support,and intentional self-regulation in optimizing students’depression,which in turn can promote better psychological states.

Relationship between family cohesion/adaptability and postpartum depressive symptoms:A single-center retrospective study

BACKGROUND Depression is the most common mental illness in postpartum mothers,and the etiology of postpartum depression remains poorly understood.Over the past several decades,studies have reported that postpartum depression is caused by multiple factors,such as genetic,psychological,pregnancy,and environmental factors,with the family environment being an important environmental factor.The theory of family cohesion and adaptability put forward by Olson is a classic model that describes the level of family function.However,to date,this model has not been examined regarding its applicability to patients with postpartum depression.AIM To investigate the relationship between family cohesion and adaptability and the risk of postpartum depressive symptoms.METHODS We retrospectively analyzed 1446 patients admitted to the postpartum healthcare clinic of the Affiliated Foshan Maternity and Child Healthcare Hospital from April 2021 to December 2021.Patients were grouped according to whether postpartum depression symptoms were reported(symptoms,n=454;no symptoms,n=992).All patients completed the Edinburgh Postpartum Depression Scale and the Chinese version of the Family Cohesion and Adaptability Assessment Scale II.Baseline and clinical data were compared between groups.Univariate regression analysis was used to investigate the association between different types of family cohesion and postpartum depressive symptoms and the association between different family adaptability types and postpartum depressive symptoms.RESULTS After adjusting for age,education,occupation,gravidity,parity,and mode of delivery,disengaged[adjusted odds ratio(AOR)=3.36,95%CI:1.91-5.91],and separated(AOR=1.97,95%CI:1.34-2.90)family cohesion types showed a higher risk of postpartum depression than the connection type,whereas the enmeshed type(AOR=0.38,95%CI:0.28-0.51)protected against postpartum depressive symptoms.Rigid(AOR=4.41,95%CI:3.02-6.43)and structured families(AOR=1.88,95%CI:1.34-2.63)had a higher risk of postpartum depressive symptoms than flexible families,whereas chaotic families(AOR=0.35,95%CI:0.24-0.51)protected against postpartum depressive symptoms.CONCLUSION Family cohesion and adaptability are influencing factors for postpartum depressive symptoms,with higher family cohesion and adaptability being associated with a lower risk of postpartum depressive symptoms.

UHPC-RC节段组合梁的抗弯性能分析

为研究低预应力度条件下,不同节段接缝的超高性能混凝土-钢筋混凝土(ultra-high performance concrete-reinforced concrete,UHPC-RC)组合梁的抗弯性能,文章基于ABAQUS有限元软件,建立UHPC-RC节段组合梁的基准有限元模型,并利用已有的试验数据验证该模型的合理性。节段接缝分别为平面干接缝、平面胶接缝、齿键干接缝和齿键胶接缝,在基准有限元模型的基础上,进一步研究节段接缝类型对组合梁抗弯性能的影响。研究发现,在四点受弯加载方式下,接缝的几何特征(平面或齿键)对组合梁的极限荷载和开裂荷载影响较小,环氧树脂胶的使用对组合梁的抗弯性能影响较大。

基于Voronoi建模和Cohesive单元的PBX细观力学模型

针对PBX的细观力学模型存在模型结构与真实PBX细观形貌不符、破坏行为描述不全面(仅考虑界面脱粘)、研究对象单一(大多针对PBX-9501)等问题,建立了基于Voronoi建模和Cohesive单元的PBX细观力学模型。首先,基于光学显微镜下的细观结构图,采用Voronoi方法构建了更贴近实际形貌的PBX炸药细观模型;然后,采用内聚力有限元方法在炸药晶体内部、黏结剂内部及炸药颗粒/黏结剂界面处都引入了Cohesive单元,以在二维尺度上实现任意路径破坏行为的模拟;最后,针对某HMX基-F2311黏结剂炸药和某HMX基-F2313黏结剂炸药标定了模型参数,模拟了这两种炸药的准静态拉伸行为。结果表明,两种炸药数值模拟的拉伸变形曲线、破坏应力、破坏应变都与试验数据吻合良好,表明该模型不仅适用于不同PBX炸药材料(线弹性PBX、非线性PBX)的变形行为描述,还可以分析PBX炸药在拉伸破坏过程中的细观机理,刻画不同PBX炸药的裂纹萌生、扩展和贯穿的过程。

Anisotropic shearing mechanism of Kangding slate:Experimental investigation and numerical analysis

The shear mechanical behavior is regarded as an essential factor affecting the stability of the surrounding rocks in underground engineering.The shear strength and failure mechanisms of layered rock are significantly affected by the foliation angles.Direct shear tests were conducted on cubic slate samples with foliation angles of 0°,30°,45°,60°,and 90°.The effect of foliation angles on failure patterns,acoustic emission(AE)characteristics,and shear strength parameters was analyzed.Based on AE characteristics,the slate failure process could be divided into four stages:quiet period,step-like increasing period,dramatic increasing period,and remission period.A new empirical expression of cohesion for layered rock was proposed,which was compared with linear and sinusoidal cohesion expressions based on the results made by this paper and previous experiments.The comparative analysis demonstrated that the new expression has better prediction ability than other expressions.The proposed empirical equation was used for direct shear simulations with the combined finite-discrete element method(FDEM),and it was found to align well with the experimental results.Considering both computational efficiency and accuracy,it was recommended to use a shear rate of 0.01 m/s for FDEM to carry out direct shear simulations.To balance the relationship between the number of elements and the simulation results in the direct shear simulations,the recommended element size is 1 mm.

Effect of slice scope on data slice-based class cohesion metrics

This paper suggests that a single class rather than methods should be used as the slice scope to compute class cohesion. First, for a given attribute, the statements in all methods that last define the attribute are computed. Then, the forward and backward data slices for this attribute are generated by using the class as the slice scope and are combined to compute the corresponding class data slice. Finally, the class cohesion is computed based on all class data slices for the attributes. Compared to traditional cohesion metrics that use methods as the slice scope, the proposed metrics that use a single class as slice scope take into account the possible interactions between the methods. The experimental results show that class cohesion can be more accurately measured when using the class as the slice scope.

基于晶体塑性模型与内聚力单元模拟的接触疲劳亚表面原奥晶界裂纹萌生

材料在接触疲劳载荷下亚表面裂纹的萌生是其主要损伤模式之一.采用晶体塑性模型耦合内聚力单元,模拟高强钢在滚动接触疲劳载荷下亚表面原奥氏体晶界处的疲劳裂纹萌生.基于内聚力模型的损伤起始准则和疲劳损伤演化规律,并利用USDFLD子程序将内聚力单元的疲劳损伤与晶体塑性模型结合,计算了滚动接触疲劳加载下的损伤随循环次数的累积.对Voronoi模型下的疲劳裂纹萌生进行了模拟,研究了晶体取向对裂纹萌生的影响.结果表明,裂纹的萌生受剪切应力主导,萌生位置在最大剪切应力范围内,模拟结果和试验观察一致.晶粒取向对裂纹萌生位置与萌生寿命有显著影响.

Systematic review of risk factors,prognosis,and management of colorectal signet-ring cell carcinoma

BACKGROUND Colorectal signet-ring cell carcinoma(CSRCC)is a rare clinical entity which accounts for approximately 1%of all colorectal cancers.Although multiple studies concerning this specific topic have been published in the past decades,the pathogenesis,associated risk factors,and potential implications on treatment are still poorly understood.Besides the low incidence,historically confusing histological criteria have resulted in confusing data.Nevertheless,the rising incidence of CSRCC along with relatively young age at presentation and associated dismal prognosis,highlight the actual interest to synthesize the known literature regarding CSRCC.AIM To provide an updated overview of risk factors,prognosis,and management of CSRCC.METHODS A literature search in the MEDLINE/PubMed database was conducted with the following search terms used:‘Signet ring cell carcinoma’and‘colorectal’.Studies in English language,published after January 1980,were included.Studies included in the qualitative synthesis were evaluated for content concerning epidemiology,risk factors,and clinical,diagnostic,histological,and molecular features,as well as metastatic pattern and therapeutic management.If possible,presented data was extracted in order to present a more detailed overview of the literature.RESULTS In total,67 articles were included for qualitative analysis,of which 54 were eligible for detailed data extraction.CSRCC has a reported incidence between 0.1%-2.4%and frequently presents with advanced disease stage at the time of diagnosis.CSRCC is associated with an impaired overall survival(5-year OS:0%-46%)and a worse stagecorrected outcome compared to mucinous and not otherwise specified adenocarcinoma.The systematic use of exploratory laparoscopy to determine the presence of peritoneal metastases has been advised.Surgery is the mainstay of treatment,although the rates of curative resection in CSRCC(21%-82%)are lower compared to those in other histological types.In case of peritoneal metastasis,cytoreductive surgery with hyperthermic intraperitoneal chemotherapy should only be proposed in selected patients.CONCLUSION CSRCC is a rare clinical entity most often characterized by young age and advanced disease at presentation.As such,diagnostic modalities and therapeutic approach should be tailored accordingly.

Study on the Development of Urban Cohesion

Urban cohesion is a new development phenomenon of urbanization, requires further study in both practices and theories. In this study, the connotation, development premise and existing problems of urbanization have been primarily explored, to obtain useful ideas.

An extended micromechanical-based plastic damage model for understanding water effects on quasi-brittle rocks

Water effects on the mechanical properties of rocks have been extensively investigated through experiments and numerical models.However,few studies have established a comprehensive link between the microscopic mechanisms of water-related micro-crack and the constitutive behaviors of rocks.In this work,we shall propose an extended micromechanical-based plastic damage model for understanding weakening effect induced by the presence of water between micro-crack’s surfaces on quasi-brittle rocks,based on the Mori-Tanaka homogenization and irreversible thermodynamics framework.Regarding the physical mechanism,water strengthens micro-crack propagation,which induces damage evolution during the pre-and post-stage,and weakens the elastic effective properties of rock matrix.After proposing a special calibration procedure for the determination of model parameters based on the laboratory compression tests,the proposed micromechanical-based model is verified by comparing the model predictions to the experimental results.The model effectively captures the mechanical behaviors of quasibrittle rocks subjected to the weakening effects of water.

Progressive fragmentation of granular assemblies within rockslides: Insights from discrete-continuous numerical modeling

Rock fragmentation plays a critical role in rock avalanches,yet conventional approaches such as classical granular flow models or the bonded particle model have limitations in accurately characterizing the progressive disintegration and kinematics of multi-deformable rock blocks during rockslides.The present study proposes a discrete-continuous numerical model,based on a cohesive zone model,to explicitly incorporate the progressive fragmentation and intricate interparticle interactions inherent in rockslides.Breakable rock granular assemblies are released along an inclined plane and flow onto a horizontal plane.The numerical scenarios are established to incorporate variations in slope angle,initial height,friction coefficient,and particle number.The evolutions of fragmentation,kinematic,runout and depositional characteristics are quantitatively analyzed and compared with experimental and field data.A positive linear relationship between the equivalent friction coefficient and the apparent friction coefficient is identified.In general,the granular mass predominantly exhibits characteristics of a dense granular flow,with the Savage number exhibiting a decreasing trend as the volume of mass increases.The process of particle breakage gradually occurs in a bottom-up manner,leading to a significant increase in the angular velocities of the rock blocks with increasing depth.The simulation results reproduce the field observations of inverse grading and source stratigraphy preservation in the deposit.We propose a disintegration index that incorporates factors such as drop height,rock mass volume,and rock strength.Our findings demonstrate a consistent linear relationship between this index and the fragmentation degree in all tested scenarios.

Evolution of mechanical parameters of Shuangjiangkou granite under different loading cycles and stress paths

Surrounding rocks at different locations are generally subjected to different stress paths during the process of deep hard rock excavation.In this study,to reveal the mechanical parameters of deep surrounding rock under different stress paths,a new cyclic loading and unloading test method for controlled true triaxial loading and unloading and principal stress direction interchange was proposed,and the evolution of mechanical parameters of Shuangjiangkou granite under different stress paths was studied,including the deformation modulus,elastic deformation increment ratios,fracture degree,cohesion and internal friction angle.Additionally,stress path coefficient was defined to characterize different stress paths,and the functional relationships among the stress path coefficient,rock fracture degree difference coefficient,cohesion and internal friction angle were obtained.The results show that during the true triaxial cyclic loading and unloading process,the deformation modulus and cohesion gradually decrease,while the internal friction angle gradually increases with increasing equivalent crack strain.The stress path coefficient is exponentially related to the rock fracture degree difference coefficient.As the stress path coefficient increases,the degrees of cohesion weakening and internal friction angle strengthening decrease linearly.During cyclic loading and unloading under true triaxial principal stress direction interchange,the direction of crack development changes,and the deformation modulus increases,while the cohesion and internal friction angle decrease slightly,indicating that the principal stress direction interchange has a strengthening effect on the surrounding rocks.Finally,the influences of the principal stress interchange direction on the stabilities of deep engineering excavation projects are discussed.

Fractures interaction and propagation mechanism of multi-cluster fracturing on laminated shale oil reservoir

The continental shale reservoirs of Jurassic Lianggaoshan Formation in Sichuan Basin contain thin lamina,which is characterized by strong plasticity and developed longitudinal shell limestone interlayer.To improve the production efficiency of reservoirs by multi-cluster fracturing,it is necessary to consider the unbalanced propagation of hydraulic fractures and the penetration effect of fractures.This paper constructed a numerical model of multi-fracture propagation and penetration based on the finite element coupling cohesive zone method;considering the construction cluster spacing,pump rate,lamina strength and other parameters studied the influencing factors of multi-cluster fracture interaction propagation;combined with AE energy data and fracture mode reconstruction method,quantitatively characterized the comprehensive impact of the strength of thin interlayer rock interfaces on the initiation and propagation of fractures that penetrate layers,and accurately predicted the propagation pattern of hydraulic fractures through laminated shale oil reservoirs.Simulation results revealed that in the process of multi-cluster fracturing,the proportion of shear damage is low,and mainly occurs in bedding fractures activated by outer fractures.Reducing the cluster spacing enhances the fracture system's penetration ability,though it lowers the activation efficiency of lamina.The high plasticity of the limestone interlayer may impact the vertical propagation distance of the main fracture.Improving the interface strength is beneficial to the reconstruction of the fracture height,but the interface communication effect is limited.Reasonable selection of layers with moderate lamina strength for fracturing stimulation,increasing the pump rate during fracturing and setting the cluster spacing reasonably are beneficial to improve the effect of reservoir stimulation.

基于LCEM-GFEM方法爆炸载荷作用下含缺陷岩体损伤机理研究

在爆破作业过程中,岩体缺陷对裂纹扩展具有显著影响。本研究基于全局有限元方法的局部黏结单元(LCEM-GFEM)方法构建数值模拟模型,研究爆破作用下含缺陷岩体的损伤演化和裂纹扩展模式。通过引入能量传递系数,定量分析了缺陷形态对应力波传播和衰减的影响。结果表明,缺陷形态对岩体的损伤特性和裂纹扩展具有显著影响。随着平行缺陷夹角的增加,爆破诱发的裂缝与衍生裂缝的合并路径从缺陷末端转移到了缺陷中间,能量传递系数增加,分形维度减小。随着平行缺陷之间的水平距离增加,平行缺陷之间的裂缝数目和能量传递系数相应减少。随着垂直缺陷之间的垂直距离增加,穿过缺陷C的主水平裂缝长度增加,能量传递系数和分形维度也增加。研究结果可为受到爆破荷载作用下含缺陷岩体的损伤特征提供指导。

Finite Element Simulations of the Localized Failure and Fracture Propagation in Cohesive Materials with Friction

Strain localization frequently occurs in cohesive materials with friction(e.g.,composites,soils,rocks)and is widely recognized as a fundamental cause of progressive structural failure.Nonetheless,achieving high-fidelity simulation for this issue,particularly concerning strong discontinuities and tension-compression-shear behaviors within localized zones,remains significantly constrained.In response,this study introduces an integrated algorithmwithin the finite element framework,merging a coupled cohesive zone model(CZM)with the nonlinear augmented finite elementmethod(N-AFEM).The coupledCZMcomprehensively describes tension-compression and compressionshear failure behaviors in cohesive,frictional materials,while the N-AFEM allows nonlinear coupled intraelement discontinuities without necessitating extra nodes or nodal DoFs.Following CZM validation using existing experimental data,this integrated algorithm was utilized to analyze soil slope failure mechanisms involving a specific tensile strength and to assess the impact of mechanical parameters(e.g.,tensile strength,weighting factor,modulus)in soils.

Constitutive Behavior of the Interface between UHPC and Steel Plate without Shear Connector:From Experimental to Numerical Study

The application of ultra-high performance concrete(UHPC)as a covering layer for steel bridge decks has gained widespread popularity.By employing a connection without a shear connector between the steel plate and UHPC,namely,the sandblasted interface and the epoxy adhesive with sprinkled basalt aggregate interface,the installation cannot only be simplified but also the stress concentration resulting from the welded shear connectors can be eliminated.This study develops constitutive models for these two interfaces without shear connectors,based on the interfacial pull-off and push-out tests.For validation,three-point bending tests on the steel-UHPC composite plates are conducted.The results indicated that the proposed bilinear traction-separation model for the sandblasted interface and the trapezoidal traction-separation model for the epoxy adhesive with sprinkled basalt aggregate interface can generally calibrate the interfacial behavior.However,the utilization of the experimentally determined pure shear strength underestimates the load-carrying capacity of the composite plates in the case of three-point bending tests.By recalling the Mohr-Coulomb criterion,this underestimation is attributed to the enhancement of the interface shear strength by the presence of normal stress.

基于内聚力单元法的船舶与重叠冰碰撞数值模拟研究

The gradual increase in shipping and drilling activities in the Arctic regions has resulted in the increased importance of studying the structural safety of polar ships in various ice conditions.Rafted ice refers to a type of accumulated and overlapped sea ice;it is driven by external forces,such as wind and waves,and may exert high loads on ships and threaten their structural safety.Therefore,the properties of rafted ice and the construction of numerical models should be studied before exploring the interaction and collision between ships and rafted ice.Based on the nonlinear finite-element method,this paper introduces the cohesive element model for the simulation of rafted ice.The interaction between ships and rafted ice is studied,and the ice force of the hull is obtained.Numerical simulation results are compared with model test findings,and the effectiveness of the cohesive element method in the construction of the model of rafted ice materials is verified.On this basis,a multilayer rafted ice model is constructed,and its interaction with the ship is studied.The research unveils that rafted ice parts impede crack generation and slow down crack propagation to a certain extent.

Effect of intermittent joint distribution on the mechanical and acoustic behavior of rock masses

The mechanical characteristics and acoustic behavior of rock masses are greatly influenced by stochastic joints.In this study,numerical models of rock masses incorporating intermittent joints with different numbers and dip angles were produced using the finite element method(FEM)with the intrinsic cohesive zone model(ICZM).Then,the uniaxial compressive and wave propagation simulations were performed.The results indicate that the joint number and dip angle can affect the mechanical and acoustic properties of the models.The uniaxial compressive strength(UCS)and wave velocity of rock masses decrease monotonically as the joint number increases.However,the wave velocity grows monotonically as the joint dip angle increases.When the joint dip angle is 45°–60°,the UCS of the rock mass is lower than that of other dip angles.The wave velocity parallel to the joints is greater than that perpendicular to the joints.When the dip angle of joints remains unchanged,the UCS and wave velocity are positively related.When the joint dip angle increases,the variation amplitude of the UCS regarding the wave velocity increases.To reveal the effect of the joint distribution on the velocity,a theoretical model was also proposed.According to the theoretical wave velocity,the change in wave velocity of models with various joint numbers and dip angles was consistent with the simulation results.Furthermore,a theoretical indicator(i.e.fabric tensor)was adopted to analyze the variation of the wave velocity and UCS.