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We have developed a general constitutive theory that estimates the effective elastic moduli of a cemented granular material by applying statistical mechanical averaging to a purely micromechanical model. We have also constructed a distinct element model of a cemented granular material, based on the same micromechanical model, which accounts for the elastic forces due to bonding between pairs of spherical particles, and which allows for the possibility of anisotropic damage to the bonds. In this paper, we use a model based on the distinct element method (DEM) to validate the predictions of the theory for various prescribed patterns of damage. In particular we impose several anisotropic patterns of damage on the bonds of a randomly generated assembly of particles. We then undertake numerical experiments, sending both p‐waves and s‐waves through the samples and measuring the wave velocities. The predictions of the theory for these velocities agree well with the results of the numerical model for a variety of damage patterns. We discuss the implications of our theory, as well as potential applications.

The distinct element method has been used to perform a number of numerical experiments, analogous to physical tests routinely carried out for real geologic materials. The ability to prescribe exactly the material properties and the boundary conditions allows us to study in detail the influence of microscopic structure on macroscopic response. These macroscopic quantities are usually the only data obtained in physical experiments. We are now in a position to formulate a general constitutive model, based on physical mechanisms and appropriate for use in a continuum code.

The notion of partner‐violence as a male‐perpetrated phenomenon is not a scientific position but an amelioration of cognitive‐dissonance within a political mindset. Against all the data, this ‘gender paradigm’ persists as a series of staged retreats as new research debunks each in turn. Supposed highly sex‐differential injury rates, male unilaterality of perpetration, female self‐defence, male ‘control’, and female especial fear are all discredited as reasons to focus solely on men's aggression. By contrast, scientific theorising regarding the root of the great bulk of partner‐violence is in terms of the biological phenomenon of mate‐guarding. However, the usual model of male proprietariness over female fertility itself is in part a ‘gender paradigm’ position. Recently revealed sex‐symmetries necessitate a major overhaul of this model. Drawing on new understanding of the basis of pair‐bonding, outlined here is a parsimonious account of mate‐guarding as being by both sexes; notably women, owing to sex‐dichotomous mate‐value trajectory. This framework heralds the complete abandonment of the ‘gender paradigm’ and thus the end of a highly inappropriate intrusion of extreme ideology into science.

We present an algorithm for contact resolution that is valid for a wide variety of polygonal two dimensional shapes and is of linear computational complexity. The algorithm is designed for use in discrete element analysis of granular and multibody systems exhibiting discontinuous behaviour. Contact detection usually consists of a spatial sorting phase and a contact resolution phase. The spatial sorting phase seeks to avoid an all‐to‐all body comparison by culling the number of objects which are potential contactors of a given object. The contact resolution phase resolves the details of the contact between two given objects. The algorithm presented here (called DFR) addresses the contact resolution phase and is applicable to convex geometries and to a restricted set of concave geometries. Examination of the algorithm establishes an upper bound linear computational complexity, of order O(N), with respect to the number of points (N) used to define the object boundary. The DFR algorithm is combined with a modified heapsort algorithm for spatial sorting of M bodies which has complexity O(M log M) and is applied to a baseline granular simulation problem to test its efficiency.

Methods used to track the free surface in numerical flow simulations, typically during the casting of metals into moulds are examined in this paper. The algorithm employed makes use of a mixed interpolation formulation to approximate the discretised governing equations for elimination on a Langrangian type moving mesh. Significant savings in CPU time are realised by virtue of the the air domain not being considered in the finite element analysis. The advantages and drawbacks of commonly used methods are discussed, and a method proposed for the numerical simulation of flow where the free surface boundary conditions are important. The effectiveness of the proposed algorithm in solving typical industrial flow problems is demonstrated using numerical examples. The results obtained are compared with analytical and numerical data with a view to validating the algorithm.

The purpose of this article is two‐fold. First, it applies the PEN‐3 model to the topic of domestic violence within the Chinese American and Chinese immigrant community. The PEN‐3 model was developed by Collins Airhihenbuwa, and it focuses on placing culture at the forefront of health promotion. It consists of three dimensions: cultural identity, relationships and expectations, and cultural empowerment. The article offers practice recommendations from the PEN‐3 analysis to plan culturally relevant and sensitive domestic violence prevention, education, and services targeted to the Chinese American and Chinese immigrant community.

Using existing literature in the areas of domestic violence and health, mental health, and counseling interventions with Chinese Americans and immigrants, the PEN‐3 model, as an organizing framework, was applied to understand the phenomenon of domestic violence among Chinese Americans and Chinese immigrants in the United States.

How Chinese Americans and Chinese immigrants perceive domestic violence and how they obtain formal assistance are embedded within a larger sociocultural context including a host of factors ranging from personal, family, community, environmental, and structural variables.

The PEN‐3 model reinforces the importance in addressing domestic violence within an ecological and cultural framework. Harnessing traditional Chinese value systems (i.e. emphasis on collectivism, hierarchy, patriarchy) and collaborating with the community are essential in promoting culturally sensitive interventions.

Practice articles examining the application of the PEN‐3 model on domestic violence among Chinese Americans and Chinese immigrants are lacking. More often than not, culture and other social forces are minimized by practitioners who are guided by “Western ways of knowing.”

The purpose of this paper is to assess the rates of HIV risk-taking behavior and sexual violence among clients with co-occurring addiction and intimate partner violence (IPV). The current study also aims to determine whether HIV risk-taking behaviors (e.g. trading sex for money or drugs, having unprotected sex with multiple partners) differ among substance using IPV offenders with and without a history of sexual aggression.

Secondary analyses were conducted from Easton et al.’s (2017) randomized controlled trial of substance use domestic violence treatment among substance using IPV offenders. Correlational analyses were conducted to assess the relationship between pre-treatment sexual aggression, HIV risk-taking behaviors, substance use and aggression. Analyses of covariance were conducted in order to determine differences in participants’ HIV risk-taking behaviors based on their history of sexual aggression while controlling for hours of contact with the female partners.

In a sample of 63 participants, males with higher rates of sexual aggression were more likely to engage in sexual risk-taking behaviors. This study encountered a correlation between pre-treatment risk-taking behavior and verbal and physical aggression, as well as a correlation between pre-treatment risk-taking behaviors and cocaine use. Results neither suggest a relationship between sexual aggression and alcohol use nor HIV risk-taking behaviors and alcohol use at pre-treatment.

The present study is limited by sample size and power.

This study is among the first of its kind to investigate HIV risk-taking behaviors among substance using offenders of IPV. This study provides support for the inclusion of treatment targeting HIV risk-taking behaviors among IPV offenders.

The purpose of this paper is to study the structure and dynamic development of a pair of co-rotating trailing vortices, during their formation, interaction and merging, using detailed experimental measurements of the velocity and vorticity fields.

The vortices were generated using two half wings (NACA0030) positioned at equal and opposite angles of attack at the entrance of the test section of an open-circuit, subsonic, wind tunnel. Velocity vector measurements were obtained at Re_c = 133,000, on cross-plane grids at several distances from the trailing edges of the wings, using an in-house developed four-sensor hot wire anemometer probe.

The results include cross-plane contour plots of the mean and fluctuating velocity as well as mean vorticity fields. Each of these variables is affected in a different way, providing complementary information on the development of the flow field. After shedding, the two vortices are swept along the stream-wise direction and spiral around each other, thereby developing a braid of two vortices, which then deforms the external flow field. Gradually, the interaction with the external flow field links both vortices together until the final merging and the formation of a new stable linear vortex emerges.

Trailing vortices have been rendered particularly important during the past decades, because of increasing traffic density of very heavy aircrafts and several plane “incidents”, which were attributed to the action of the vortex wake.

The presented results provide information on the evolution and merging of a pair of vortices formed by a closely spaced differential wing configuration. The vortices interact almost immediately after shedding as expected in flap–flap or flap–wing vortices interaction.

The simulation of the fluid–solid interaction (FSI) problem is important for both academic studies and engineering applications. However, the numerical approach for simulating the FSI problems is a great challenge owing to the large discrepancy of material properties and inconsistent description of grid motion between the fluid and solid domains. The difficulties will be further increased if there are multiple materials in the fluid region. In these complicated applications, interface reconstruction, multi-material advection and FSI must be all taken into account. This paper aims to present an effective integrated work of multi-material arbitrary Lagrangian Eulerian (MMALE) method, finite element (FE) method and the continuum analogy method to simulate the complex FSI problems involving multi-material flow. The coupled method is used to simulate the three-dimensional CONT test and the blast-plate interaction. The numerical results show good agreement with the benchmark and the experiment data, which indicates that the presented method is effective for solving the complicated FSI problems.

MMALE and FE methods are used to simulate fluid and solid regions, respectively. The interfacial nodes of fluid and solid are required to be coincident in the whole simulation so the interacted force can be easily and accurately calculated. To this end, the continuum analogy method is used in the rezoning phase.

The coupled method is used to simulate the three-dimensional CONT test and the blast-plate interaction. The numerical results show good agreement with the benchmark and the experiment data, which indicates that the presented method is effective for solving the complicated FSI problems.

To the best of the authors’ knowledge, this is the first time that the ALE method, moment of fluid interface reconstruction method, continuum analogy method and the FE method are combined to solve complicated practical problems.