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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 brief announcement that the Government had accepted that there should be regulations on open date marking of food, to come into effect in 1975, will come as no surprise. It is a timely reminder of what public pressure can achieve these days; how sustained advocacy and publicity by interested sectors of society—magistrates, local authorities, public health workers, consumer groups—can secure legislative changes which, in this case, run counter to trade opinions and the recommendation originally made by the Food Standards Committee that such a proposal was not practical and the existing law was an adequate protection. This was stated in the FSC Report on Food Labelling of 1964, although there was no indication of the evidence reviewed or that the subject had been considered very deeply; it was, after all, only a small fraction of the problem of food labelling control. It was also stated in this Report that in certain cases, date‐stamping of food could give to purchasers a false sense of security, “not justified by the conditions under which the food has been kept since manufacture”.

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.

Discrete element methods are numerical procedures for simulating the complete behaviour of systems of discrete, interacting bodies. Three important aspects of discrete element programs are examined: (1) the representation of contacts; (2) the representation of solid material; and (3) the scheme used to detect and revise the set of contacts. A proposal is made to define what constitutes a discrete element program, and four classes of such programs are described: the distinct element method, modal methods, discontinuous deformation analysis and the momentum‐exchange method. Several applications and examples are presented, and a list is given of suggestions for future developments.

The United States (US) system of special education committed three original sins that perpetuate inequities between children with disabilities and their peers. The purpose of this paper is to examine the history of the US system, contrast this history against international disability law and identify opportunities for leaders to transform policy and practice for inclusive education.

This paper explores the development of the three sins in US special education law: (1) weaving throughout it a medical model of disability, (2) failing to mandate inclusion and (3) hampering meaningful enforcement. The paper contrasts the US system with the United Nations (UN) Convention on the Rights of Persons with Disabilities (CRPD), an international law adopted by 180 nations that requires inclusion of people with disabilities at all levels of systems.

This paper finds that the United States has not embraced inclusion in education, but has permitted a continuum of segregation and integration. After a discussion of the three sins and the CRPD, the authors describe opportunities for international and US leaders to learn from the original sins of the United States and develop a system of true inclusion for all students through the transformation of policy and practice.

This paper contributes to the literature on policy development and implementation, with implications for future amendments to US education law and international public administration of education.

Little attention is given to black male experiences and decision-making process around college-going. A qualitative study (interpretive phenomenological analysis [IPA]) was conducted using a strengths-based perspective to understand the experiences of three first-generation black men college students attending a predominately white institution. Superordinate themes include perceived benefits to attending college, barriers to college admission and attendance and influential programs and supports. Recommendations for school counselors helping black males are included.

The authors used a narrative approach to illustrate the stories and experiences captured by the three young men who participated in the study. Hays and Singh (2012) suggested using a narrative approach for telling the stories of marginalized groups. IPA (Smith, 1996) was the approach used to identify superordinate themes, because the authors wanted to better understand the participants’ K-16 experiences. As a qualitative approach, IPA provides detailed examinations of personal lived experiences on its own terms rather than pre-existing theoretical preconceptions.

The participants’ accounts clustered around three superordinate themes: perceived benefits to college, barriers to college admission and attendance and influential programs and supports.

Although there are studies that provide insight on the factors that impact first-generation, black men’s success in attending college, there are few studies that have used a strengths-based perspective to investigate key experiences that lead to college enrollment. Those experiences that lead first-generation black male to attend college are pivotal and provide insight into important points of intervention and support. School counselors and other educators can use these insights to inform practices and the creation of supports for black men in their respective schools.

Aarhus Kommunes Biblioteker (Teknisk Bibliotek), Ingerslevs Plads 7, Aarhus, Denmark. Representative: V. NEDERGAARD PEDERSEN (Librarian).

This paper reports the use of situational analysis as a systems methodology to evaluate the voices of independence change and empowerment in the Stoke-on-Trent (VOICES) partnership project.

Using situational analysis and drawing on a range of secondary data sources, a three-stage conceptual mapping process provided a detailed picture of both the non-linear interlinkage and complexity of the local system that VOICES was working to influence, as well as the processes that shaped the experiences of those who act within the situation.

Data highlighted the systemic challenges facing VOICES customers (e.g. stigma and marginalisation and lack of legal literacy), progress made by VOICES in each of their priority areas and an overarching theme of VOICES promoting equity (rather than equality) to address failure demand in the system of support for people with multiple needs and disadvantage.

The authors present the novel application of situational analysis to demonstrate a substantial impact of VOICES while demonstrating the value of this methodology for complex systems thinking research and evaluation.

It has often been said that a great part of the strength of Aslib lies in the fact that it brings together those whose experience has been gained in many widely differing fields but who have a common interest in the means by which information may be collected and disseminated to the greatest advantage. Lists of its members have, therefore, a more than ordinary value since they present, in miniature, a cross‐section of institutions and individuals who share this special interest.