Static and Dynamic Analysis of Cracked Concrete Beams Using Experimental Study and Finite Element Analysis

In this paper, a simple method for defining the effects of cracks on elastic behavior of beam is presented. The cracked sections were modelled as rotational springs and the problem was solved using the finite element method. The global stiffness matrix of a beam with multiply cracked section was then assembled. For calculation of rotational spring stiffness equivalent to uncracked and cracked sections, finite element models and experimental test were used.The natural frequencies and mode shape of beams with multiple single-edge cracks were obtained and a new simple formula was proposed. Published numerical examples for cracked beams were used for validation

A Numerical Method for Eigensolution of Near-Regular Structural and Mechanical Systems

In this paper a numerical method is developed to find the eigenvalues of the Laplacian matrix for near-regular graph models. Considering the similarity between the pattern of the Laplacian matrix of a graph and the stiffness matrix of a structure, the method can be used for the eigensolution of structural/mechanical systems. Previously, using graph product rules algorithms for the swift solution of the equation F = K∆ in structural/mechanical systems were developed. In this study, using a purposeful ordering along with partitioning the Laplacian/stiffness matrix, a decomposable pattern is achieved. The decomposed parts are solved using combined graph product rules and numerical solutions. While the eigensolution of regular patterns has been traditionally considered as an approximation for near-regular patterns, here the solution of the regular pattern is utilized as an appropriate initial starting point for the solution of near-regular pattern. Furthermore, solving the decomposed regular part using graph product rules reduces the computational complexity of the method

Commercial Space Activity Law: Necessities and Strategies

Commercialization of space is happening much faster than expected. However, in space law, due to the share of the five treaties at the time of their conclusion and ratification, less attention has been paid to the commercial dimensions of space, so the logic of international relations requires that space regulations be developed in proportion to this growing trend. The non-conformity of regulations with the development of business activities poses challenges to the international community in adopting binding laws, which has led countries to regulate this area to meet the needs of domestic business actors. The development of commercial uses of space such as space tourism, space transportation, natural resource exploitation, the need for rules, updating and transparency of regulations, especially in areas such as property ownership (both real and intellectual), financing of space assets, and space mining is essential. The present article, while enumerating the basic needs and strategies in this field along with soft laws and the actions of various space law actors as one of the practical ways of regulating space activities, explains the existing regulations such as the space protocol to the Cape Town Convention on investment in the space industry

Evolution of the Concept of Public Morality and Principles of its criminalization: Philosophical and Human Rights Approaches

AbstractMany codes advocating public morals have been challenged during recent years. The decriminalization of immoral acts, as one of the most important aspects of modern criminal law, has been rooted in the arguments of scholars such as John Stuart Mill and Joel Feinberg on the state intervention in individual liberties. These scholars by developing freedom restricting principles have advocated a kind of minimalist criminalization in the sphere of public morality. Moreover, the international human rights law system, in an effort to balance cultural diversity and universal values, has endorsed public morality as one of the permissible restrictions on unrestricted civil-political liberties. In fact, following developments in the performance of governments in the field of public morality, the international human rights system, by providing a progressive interpretation of the principles governing criminalization, reject the legal moralism has attempted to defend a kind of rights-oriented criminalization that protects the rights and freedoms of vulnerable people

Test Anxiety and Relaxation Training in Third-Grade Students

As testing becomes an achievement marker for elementary school children, test anxiety would naturally follow for these children. This study looks at test anxiety in third grade students, as well as relaxation training as a treatment modality to deal with that anxiety. One hundred and four third grade students participated in this study. Those students that received relaxation training experienced less test anxiety after the treatment. Students in the control group showed no changes in test anxiety. The use of relaxation training among third grade students may be a beneficial method for teachers to reduce anxiety in their students

Dissociative Symptoms and Self-Reported Childhood and Current Trauma in Male Incarcerated People with Borderline Personality Disorder - Results from a Small Cross-Sectional Study in Iran

There is evidence that incarcerated people show higher rates of symptoms of psychopathology. In the present study, we assessed male Iranian incarcerated people with borderline personality disorders (BPD) and investigated the occurrence of past and current trauma and their associations with dissociative experiences.; A total of 69 male Iranian incarcerated people (mean age: 33.76 years) diagnosed with PBD completed questionnaires covering sociodemographic information, dissociative experiences, and past and current traumatic events.; Participants reporting the occurrence of childhood trauma also reported the occurrence of adulthood trauma. Dissociation and adulthood trauma were associated in a U-shaped, non-linear fashion: Low and high adulthood trauma were associated with higher dissociation. Younger age, the presence of childhood trauma, and being single or divorced predicted adulthood trauma.; The pattern of results suggests that both childhood and adulthood trauma are highly prevalent among male incarcerated people, while the association between adulthood trauma and dissociation appeared to be more complex. When treating male incarcerated people, a complex interplay between past and current traumas and dissociation should be considered

Topology optimization for the seismic design of truss-like structures

A practical optimization method is applied to design nonlinear truss-like structures subjected to seismic excitation. To achieve minimum weight design, inefficient material is gradually shifted from strong parts to weak parts of a structure until a state of uniform deformation prevails. By considering different truss structures, effects of seismic excitation, target ductility and buckling of the compression members on optimum topology are investigated. It is shown that the proposed method could lead to 60% less structural weight compared to optimization methods based on elastic behavior and equivalent static loads, and is efficient at controlling performance parameters under a design earthquake. © 2010 Elsevier B.V