We develop and test Quantum Monte Carlo algorithms that use a"twist" or a phase in the wave function for fermions in periodic boundary conditions. For metallic systems, averaging over the twist results in faster convergence to the thermodynamic limit than periodic boundary conditions for properties involving the kinetic energy and has the same computational complexity. We determine exponents fo...

In August of 2007 and December of 2007, North American academic researchers, industry representatives and regulators were invited to meetings in Washington and Minneapolis, respectively, with the goal of forming a Software Certification Consortium (SCC). At the first meeting, objectives were established for the consortium and a certification grand challenge was issued. At the second meeting, al...

background: back and shoulder pain are most common musculoskeletal disorders in students, that the way of sitting or interactions with academic equipment is a major risk factor for these disorders.  the aims of this study is redesign and construct a prototype of painting chair (kharak) by using industrial design and ergonomic methods to reduce musculoskeletal disorders and increase user satisfa...

Abstract This study discusses how the role of entrepreneurship in addressing so-called “grand challenges” (e.g., poverty, inequality, pollution, climate change) is evolving and could further evolve, based on ongoing conversation scholarly community. To develop discussion, we conducted following steps: (1) a computer-aided semantic analysis; (2) an analysis evolution literature streams; (3) netw...

Even though there has been a proliferation of e-society measures in recent years, analyses of the metrics of the “information society” are still far from responsive to the needs of many stakeholders and continue to suffer from a number of serious limitations. Issues in eight critical areas are briefly presented. They include: definition of the universe to be measured; definition of the objects ...

As the next generation of engineers, engineering students at the local level have specific views on what key issues should be addressed in the coming decades. Results of a University of Kansas survey completed by over 220 engineering students from sophomores to graduate students in seven engineering majors from five departments are reported, analyzed, and compared with the 14 Grand Challenges f...

We consider several structured population models (age structured, size structured, maturity structured) and the general scattering equation. These models are not conservation laws, nevertheless we show that they admit a common relative entropy structure which uses the first eigenelements of the problem. In case of scattering, it is more general than the usual ”detailed balance principle”. Three...

avian leukosis viruses (alvs) cause different types of tumours in poultry and can affect the health and egg production of the birds. to investigate the presence of the virus in chicken layer flocks in shiraz, 222 egg albumen from local layer breeder (25 eggs), local layer grand parent (30 eggs), broiler breeder (60 eggs), commercial layer (46 eggs) and broiler grand parent (61 eggs) were tested...

“One of the better aspects of human nature is our drive to seek out and conquer challenges. We seem imbued with a desire to formulate problems of the highest degree of difficulty and then to relentlessly pursue their solution. The identification and pursuit of Grand Challenges has been a hallmark of the high-performance computing arena for over a decade. In recent years, many other technical co...