A performance comparison of the contiguous allocation strategies in 3D mesh connected multicomputers

The performance of contiguous allocation strategies can be significantly affected by the distribution of job execution times. In this paper, the performance of the existing contiguous allocation strategies for 3D mesh multicomputers is re-visited in the context of heavy-tailed distributions (e.g., a Bounded Pareto distribution). The strategies are evaluated and compared using simulation experiments for both First-Come-First-Served (FCFS) and Shortest-Service-Demand (SSD) scheduling strategies under a variety of system loads and system sizes. The results show that the performance of the allocation strategies degrades considerably when job execution times follow a heavy-tailed distribution. Moreover, SSD copes much better than FCFS scheduling strategy in the presence of heavy-tailed job execution times. The results also show that the strategies that depend on a list of allocated sub-meshes for both allocation and deallocation have lower allocation overhead and deliver good system performance in terms of average turnaround time and mean system utilization

Energy analysis of wall materials using building information modeling (BIM) of public buildings in the tropical climate countries

During the previous two decades, the energy saving potential using systematic building management is considered to be important which should be considered through the building lifecycle. Among the wide range types of different buildings, Public buildings are considered as one of the biggest energy-consuming sector in the world and major part of this amount is used by the air conditioning system especially in tropical climates. The most effective decisions related to sustainable design of a building facility are made in the feasibility and early design stages. Building Information Modeling (BIM) can expedite this process and provide the opportunity of testing and assessing different design alternatives and materials selection that may impact on energy performance of buildings. This paper aims at evaluating the efficiency of various types of wall materials with regard to theirs properties on energy saving. The case study in this paper is modeled by means of BIM application and then simulated by software, which is appropriate for energy analysis. The current energy consumption patterns of this case identified and shifted to the optimized level of energy usages by changing the walls materials to find most optimized of walls materials. Modification most optimized wall materials and energy analysis indicated 9347 Wh in Per meter square of electrical energy saving

Revealing initial state properties through ultra-central symmetric heavy-ion collisions

Heavy-ion experiments provide a new opportunity to gain a deeper understanding of the structure of nuclei. To achieve this, it is crucial to identify observables under circumstances that are minimally affected by the process that leads to the initial state of heavy-ion collisions from nuclear wavefunction. In this study, we demonstrate that when assuming scale-invariance, the effect of this stage on the initial energy or entropy density moments in ultra-central symmetric collisions is negligible for nucleon sizes of approximately 0.7 fm or larger for large nuclei. By borrowing cluster expansion method from statistical physics and using scale-invariance assumption, we calculate the average ellipticity of initial density at the presence of short-range correlation. We compare our calculations to Monte Carlo studies and assess the accuracy of various methods of short-range correlation sampling. Additionally, we find that the isobar ratio can constrain the initial state parameters, in addition to deformation. Our study indicates that the isobar ratios in ultra-central collisions are especially sensitive to the fluctuation in the weight of the nuclei constituents and the two-body correlation among nucleons. This insight is crucial for drawing conclusions about nuclear deformations based on isobar ratios.Comment: 32 pages, 10 figure

Negative life-cycle emissions growth rate through retrofit of existing institutional buildings: Energy Analysis and Life Cycle Assessment of a Case Study of University Dormitory Renovation

ABSTRACT: Buildings account for about one fifth of the world`s total delivered energy use, and thus methods for reducing energy consumption and carbon emission associated with buildings are crucial elements for climate change mitigation and sustainability. Voluntary challenges, mandates, and, particularly, public institutions have articulated these goals in terms of striving for “net-zero energy” buildings, and mandated measurable reductions in greenhouse gas emissions. Typically, the definition of net-zero and other energy consumption reduction goals only consider operational energy. By ignoring embodied energy during the entire life-cycle of the building (manufacture, use and demolition of materials and systems), such goals and mandates may drive suboptimal decisions in terms of cost-effective greenhouse gas emission reductions. Many new buildings will require decades of net-zero operational energy consumption to negate climate change and other environmental impacts during the construction process. Additionally, if a new building is part of a portfolio of institutional buildings, even with net-zero energy consumption, the most optimistic scenario is the eventual reduction of emission growth rate to zero. A more productive approach for reducing the life-cycle energy in a building and associated negative environmental impacts may be to focus on retrofitting existing buildings. However, since large investments in existing building stock can be difficult to justify and approve in an institutional context, fixed portions of life-cycle costs also highlight the importance of maximizing the operational energy impact associated with any renovation. This study uses life-cycle analysis to evaluate efficacy of energy retrofits for an existing institutional building located on the University of Massachusetts Amherst campus. Using data, energy models, and life-cycle analysis tools for an actual energy retrofit on an existing residential building, this study will show how poor controls and failing to address thermal bridges can affect our model expectations. By developing a process for life cycle based evaluating retrofit options this study will explore the implication of producing an institution-wide negative net-energy growth rate

Theoretical aspects of relativistic spin hydrodynamics coupled with electromagnetic fields

We expand the classical phase-space distribution function to incorporate couplings between spin and electromagnetic fields. This extension has led to the derivation of modified constitutive relations for the charge current, energy-momentum tensor, and spin tensor. Due to these couplings, the new tensors are revised from their perfect fluid analogues, creating an interplay between the background and spin fluid equations of motion. The corrections introduced in our framework have the potential to shed light on the experimentally observed discrepancies in the spin polarization measurements of Lambda hyperons.Comment: Contribution to SPIN 2023 conferenc