The Coupled Cluster Method in Hamiltonian Lattice Field Theory

The coupled cluster or exp S form of the eigenvalue problem for lattice Hamiltonian QCD (without quarks) is investigated. A new construction prescription is given for the calculation of the relevant coupled cluster matrix elements with respect to an orthogonal and independent loop space basis. The method avoids the explicit introduction of gauge group coupling coefficients by mapping the eigenvalue problem onto a suitable set of character functions, which allows a simplified procedure. Using appropriate group theoretical methods, we show that it is possible to set up the eigenvalue problem for eigenstates having arbitrary lattice momentum and lattice angular momentum.Comment: LaTeX, no figur

Twitter, Google, iPhone/iPad, and Facebook (TGIF) and Smart Technology Environments: How Well Do Educators Communicate with Students via TGIF?

This article is a summary of a 2011 Association for Information Systems Americas Conference on Information Systems (AMCIS) panel discussion regarding current issues and future directions in the use of mobile technologies and social networks in education. The invited panelists are four faculty members from the United States specializing in Information Systems. The covered topics included evolution and history of e-learning, use of smartphones and tablets in education, development of social network services, and the use of social media (i.e., teaching with blogs and wikis) in the classroom. We discuss future directions in Twitter, Google, iPhone/iPad, and Facebook technology environments. Several resources for social media for college instructors are provided in the Appendix

Validating Perception and Use of Mobile Social Network Service: A Cross-Cultural Comparison Study

The rapid developments of Social Network Services (SNS) and mobile technology have offered opportunities to revisitseminal theories of technology use in today’s socio-technical environment. Mobile technology based SNSprovides various service channels that are highly correlated with their respective service contexts, in which culturalinfluences are omnipresent. Investigating use intention in a cross-cultural mobile SNS study implies new theoreticaldiscoveries and managerial practices. This research in progress (RIP) paper suggests that important distinctions existbetween U.S. and Chinese SNS subscribers in terms of SNS use and perceptions. Taking the perspective of SNSusers, we strive to explore the effects of cultural factors (e.g., collectivism vs. individualism) on trust formulation,degree of social awareness, and privacy concern. We examine the antecedents and consequences of legacyconstructs (e.g., technology acceptance and social capital) in SNS. This paper describes the research design to testthe research hypotheses. A triangulation methodology (i.e., qualitative and quantitative methods) is desired andproposed in the design. A discussion of research implications and business practices is also included in this RIPpaper

Social Networking and Social Media in the United States, South Korea, and China

This article summarizes the panel discussion at Americas Conference on Information Systems (AMCIS) 2012 on the social media environment around the world, particularly the United States, South Korea, and China. The panelists discussed the current status of social networking and social media in the aforementioned countries. The first section begins with United States, with social networking pertaining to the population at large, the use of social networks in the business environment, and observed overuse and addictive behavior of wireless mobile devices (WMD) among users. The second section covers South Korea, with the discussion addressing social networking sites (SNS) and its history; the collectivism of Asian culture and how it affects users’ behavior toward SNS; current trends, which include privacy concerns; and the future direction of SNS in Korea. Finally, in China, social media is further explored in the business models of SNS providers, followed by the customer base comparison between the United States and China

Habitable Zones of Host Stars During the Post-MS Phase

A star will become brighter and brighter with stellar evolution, and the distance of its habitable zone will become farther and farther. Some planets outside the habitable zone of a host star during the main sequence phase may enter the habitable zone of the host star during other evolutionary phases. A terrestrial planet within the habitable zone of its host star is generally thought to be suited to life existence. Furthermore, a rocky moon around a giant planet may be also suited to life survive, provided that the planet-moon system is within the habitable zone of its host star. Using Eggleton's code and the boundary flux of habitable zone, we calculate the habitable zone of our Solar after the main sequence phase. It is found that Mars' orbit and Jupiter's orbit will enter the habitable zone of Solar during the subgiant branch phase and the red giant branch phase, respectively. And the orbit of Saturn will enter the habitable zone of Solar during the He-burning phase for about 137 million years. Life is unlikely at any time on Saturn, as it is a giant gaseous planet. However, Titan, the rocky moon of Saturn, may be suitable for biological evolution and become another Earth during that time. For low-mass stars, there are similar habitable zones during the He-burning phase as our Solar, because there are similar core masses and luminosities for these stars during that phase.Comment: 6 pages, 7 figures. Accepted by Ap & S

Bring Your Own Device (BYOD): Current Status, Issues, and Future Directions

The smart mobile device has emerged as an extension of the self, closely tied to the personal behaviors and preferences. This panel discussion covers the current status, real world cases, adoption, pros/cons, issues (security, privacy), and future direction of the use and adoption of Bring-Your-Own-Device (BYOD). The panel also covers BYOS (Bring-Your-Own-Service) and BYOA (Bring-Your-Own-Apps)

Decay and Continuity of Boltzmann Equation in Bounded Domains

Boundaries occur naturally in kinetic equations and boundary effects are crucial for dynamics of dilute gases governed by the Boltzmann equation. We develop a mathematical theory to study the time decay and continuity of Boltzmann solutions for four basic types of boundary conditions: inflow, bounce-back reflection, specular reflection, and diffuse reflection. We establish exponential decay in $L^{\infty}$ norm for hard potentials for general classes of smooth domains near an absolute Maxwellian. Moreover, in convex domains, we also establish continuity for these Boltzmann solutions away from the grazing set of the velocity at the boundary. Our contribution is based on a new $L^{2}$ decay theory and its interplay with delicate $$ decay analysis for the linearized Boltzmann equation, in the presence of many repeated interactions with the boundary.Comment: 89 pages

Argon annealing of the oxygen-isotope exchanged manganite La_{0.8}Ca_{0.2}MnO_{3+y}

We have resolved a controversial issue concerning the oxygen-isotope shift of the ferromagnetic transition temperature T_{C} in the manganite La_{0.8}Ca_{0.2}MnO_{3+y}. We show that the giant oxygen-isotope shift of T_C observed in the normal oxygen-isotope exchanged samples is indeed intrinsic, while a much smaller shift observed in the argon annealed samples is an artifact. The argon annealing causes the 18O sample to partially exchange back to the 16O isotope due to a small 16O contamination in the Ar gas. Such a contamination is commonly caused by the oxygen outgas that is trapped in the tubes, connectors and valves. The present results thus umambiguously demonstrate that the observed large oxygen isotope effect is an intrinsic property of manganites, and places an important constraint on the basic physics of these materials.Comment: 4 pages, 3 figures, submitted to PR

Tibetan sheep are better able to cope with low energy intake than Small-tailed Han sheep due to lower maintenance energy requirements and higher nutrient digestibilities

Tibetan sheep are indigenous to the Qinghai-Tibetan Plateau (QTP) and are well-adapted to and even thrive under the harsh alpine conditions. Small-tailed Han sheep were introduced to the plateau because of their high prolificacy and are maintained mainly in feedlots. Because of their different backgrounds, we hypothesised that Tibetan and Small-tailed Han sheep would differ in their utilization of energy intake and predicted that Tibetan sheep would cope better with low energy intake than Small-tailed Han sheep. To test this prediction, we determined nutrient digestibilities, energy requirements for maintenance and blood metabolite and hormone concentrations involved in energy metabolism in these breeds. Sheep of each breed (n = 24 of each, all wethers and 1.5 years of age) were distributed randomly into one of four groups and offered ad libitum diets of different digestible energy (DE) densities: 8.21, 9.33, 10.45 and 11.57 MJ DE/kg Dry matter (DM). Following 42 d of measuring feed intake, a 1-week digestion and metabolism experiment was done. DM intakes did not differ between breeds nor among treatments but, by design, DE intake increased linearly in both breeds as dietary energy level increased (P < 0.001). The average daily gain (ADG) was significantly greater in the Tibetan than Small-tailed Han sheep (P = 0.003) and increased linearly in both breeds (P < 0.001). In addition, from the regression analysis of ADG on DE intake, daily DE maintenance requirements were lower for Tibetan than for Small-tailed Han sheep (0.41 vs 0.50 MJ/BW0.75, P < 0.05). The DE and metabolizable energy (ME) digestibilities were higher in the Tibetan than Small-tailed Han sheep (P < 0.001) and increased linearly as the energy level increased in the diet (P < 0.001). At the lowest energy treatment, Tibetan sheep when compared with Small-tailed Han sheep, had: 1) higher serum glucose and glucagon, but lower insulin concentrations (P < 0.05), which indicated a higher capacity for gluconeogenesis and ability to regulate glucose metabolism; and 2) higher non-esterified fatty acids (NEFA) and lower very low density lipoprotein (VLDL) and triglyceride (TG) concentrations (P < 0.05), which indicated a higher capacity for NEFA oxidation but lower ability for triglyceride (TG) synthesis. We concluded that our prediction was supported as these differences between breeds conferred an advantage for Tibetan over Small-tailed Han sheep to cope better with low energy diets

Reconstructing initial data using observers: error analysis of the semi-discrete and fully discrete approximations

A new iterative algorithm for solving initial data inverse problems from partial observations has been recently proposed in Ramdani et al. (Automatica 46(10), 1616-1625, 2010 ). Based on the concept of observers (also called Luenberger observers), this algorithm covers a large class of abstract evolution PDE's. In this paper, we are concerned with the convergence analysis of this algorithm. More precisely, we provide a complete numerical analysis for semi-discrete (in space) and fully discrete approximations derived using finite elements in space and an implicit Euler method in time. The analysis is carried out for abstract Schrödinger and wave conservative systems with bounded observation (locally distributed)