Software Partitioning and Scheduling for Improving Performance and Energy Consumption

With the advances of the contemporary computer technology, the complexity grows significantly in both hardware architecture and software application. In order to meet the performance requirement of target applications, more and more emphasis is put on the compiler techniques to exploit both hardware and software parallelism. Scheduler, an important compiler component to allocate operations to hardware resources, is crucial to the success of a computing system. In this thesis, several novel scheduling optimization techniques are presented to address the challenge faced by existing computing architectures and applications. The first targeted architecture is a system with memory hierarchy and processor comprising multiple processing and memory units. Loop partition scheduling technique is proposed to take advantage of the memory hierarchy and effectively hide the memory access latency for the loop-intensive applications. The concept of balanced partition schedule is presented to achieve the best memory access latency toleration and hardware resource utilization. Various extensions of the base problem are studied in depth. The solution are presented for the system model with multiple-level memory hierarchy, memory size constraint and loop model with initial data and multiple nested loops. Multiple cluster architecture becomes more and more popular due to its superiority over centralized architecture. Inter-cluster communication, achieved by explicit register-to-register move, is compiler-controlled and invisible to the programmer. The thesis proposes an efficient scheduling algorithm which take into account ILP, register file size and inter-cluster communication constraints. Furthermore, the solution is completed by deliberate the effect of distributed caches. The consideration of data spilling, cache conflicts and cache communications are integrated into the algorithm. Another target architecture is multi-bank memory architecture, which brings the scheduling complexity and difficulty of variable partitioning. The approach in the thesis not only improves the existing techniques when exploiting the parallelism, but also considers the serialism to take advantage of multiple operating modes of the memory banks. By identifying the best tradeoff between parallelism and serialism, both goals of performance and energy saving can be achieved. A novel memory access graph model, which captures both information of parallelism and serialism, forms the basis for this scheduling approach.</p

Palladium-Catalyzed Nucleophile−Alkyne−α,β-Unsaturated Carbonyl Coupling through Tandem Nucleopalladation and Conjugate Addition

Palladium-Catalyzed Nucleophile−Alkyne−α,β-Unsaturated Carbonyl Coupling through Tandem Nucleopalladation and Conjugate Additio

Sub-50 nm focusing of 405 nm laser by hemispherical silicon nanolens

In this work, we study the light focusing behaviors of sub-micron Si hemispherical nanolens in theory. Results show that the width and depth of the focus spot light at 405 nm can reach 42 nm (approximately {\lambda}/10) and 20 nm ({\lambda}/20), respectively. Theoretical analysis indicates that this nano-focusing phenomenon comes from two reasons, the high refractive index of Si and the sub-micro size of the lens which considerably decrease the influence of material losses. The focusing capability of Si nanolens is comparable with current EUV technique but with a low cost, providing an alternative approach towards super-resolution photolithography and optical microscopy

Trends of non-union and prescriptions for non-steroidal anti-inflammatory drugs in the United States, 1993–2012

<div><p><b>Background and purpose —</b> Surgical care and pain management for patients with fractures have evolved over the years. We wanted to ascertain if there were any changes in the incidence of non-unions and, if so, whether the use of non-steroidal anti-inflammatory drugs (NSAIDs), including COX-2 selective inhibitors, might have an effect.</p><p><b>Patients and methods —</b> We used the National Inpatient Sample (NIS) to estimate the annual number of patients hospitalized for surgical treatment of a non-union between 1993 and 2012, and calculated age-adjusted rates of non-union. We estimated the prevalence of prescriptions for NSAIDs from 1996 through 2012 using the Medical Expenditure Panel Survey (MEPS). The interrupted time-series analysis was used to relate quarterly rates of non-union to changes in prescriptions for NSAIDs between 1996 and 2009.</p><p><b>Results —</b> The annual estimate of non-unions in the USA declined 30% from 25,634 in 1993 to 17,815 in 2012 (p < 0.001). Specifically, the age-adjusted rate of non-unions decreased by 44% from 8.6 per 10⁵ persons in 1996 to 4.8 per 10⁵ persons in 2012 (p < 0.001). However, there was an 8% increase in the incidence rate of non-unions (p = 0.003) between 2000 and 2004, when certain COX-2 selective inhibitors were on the market and their prescriptions were prevalent at around 6% among those with fractures. A drop in non-union estimates from 22,321 in 2010 to 18,789 in 2011 (p = 0.04) also coincided with a marked decrease in prescriptions for NSAIDs in patients with fractures, from 22% to 14% (p = 0.02).</p><p><b>Interpretation —</b> Non-unions in the USA declined substantially between 1993 and 2012, but this was interrupted by changes in prescriptions for NSAIDs, with sustained increases between 2000 and 2004 followed by transient decreases in 2005 and 2011.</p></div

Edge states and topological invariants of non-Hermitian systems

The bulk-boundary correspondence is among the central issues of non-Hermitian topological states. We show that a previously overlooked `non-Hermitian skin effect' necessitates redefinition of topological invariants in a generalized Brillouin zone. The resultant phase diagrams dramatically differ from the usual Bloch theory. Specifically, we obtain the phase diagram of non-Hermitian Su-Schrieffer-Heeger model, whose topological zero modes are determined by the non-Bloch winding number instead of the Bloch-Hamiltonian-based topological number. Our work settles the issue of the breakdown of conventional bulk-boundary correspondence and introduces the non-Bloch bulk-boundary correspondence

Green's functions of multiband non-Hermitian systems

Green's functions of non-Hermitian systems play a fundamental role in various dynamical processes. Because non-Hermitian systems are sensitive to boundary conditions due to the non-Hermitian skin effect, open-boundary Green's functions are closely related to the non-Bloch band theory. While the exact formula of open-boundary Green's functions in single-band non-Hermitian systems proves to be an integral along the generalized Brillouin zone (GBZ), the proper generalization in generic multiband systems remains unclear. In this work, we derive a formula of open-boundary Green's functions in multiband non-Hermitian systems by viewing the multiband GBZ on the Riemann surface. This formula can be applied to describe directional amplification in multiband systems, which can be verified at various experimental platforms

A General Route to 4-Imidazolyl-Containing Multidentate Ligands for Biomimetic Studies

4-Iodo-1-tritylimidazole undergoes magnesium−iodine exchange with a Grignard reagent to give selectively the 4-magnesioimidazole derivative, which reacts with esters to form a variety of poly-4-imidazolyl carbinol compounds in 40−79% yields. A wide range of bi-, tri-, and pentadentate ligands featuring 4-substituted imidazole units have been efficiently synthesized

Amoeba formulation of the non-Hermitian skin effect in higher dimensions

The non-Hermitian skin effect dramatically reshapes the energy bands of non-Hermitian systems, meaning that the usual Bloch band theory is fundamentally inadequate as their characterization. The non-Bloch band theory, in which the concept of Brillouin zone is generalized, has been widely applied to investigate non-Hermitian systems in one spatial dimension. However, its generalization to higher dimensions has been challenging. Here, we develop a formulation of the non-Hermitian skin effect and non-Bloch band theory in arbitrary spatial dimensions, which is based on a natural geometrical object known as the amoeba. Our theory provides a general framework for studying non-Hermitian bands beyond one dimension. Key quantities of non-Hermitian bands, including the energy spectrum, eigenstates profiles, and the generalized Brillouin zone, can be efficiently obtained from this approach

Effect of Halide Ligands on the Reactivity of Carbon−Palladium Bonds: Implications for Designing Catalytic Reactions

The integral role of halide ions as a ligand in divalent palladium-catalyzed nucleophile−alkyne−α,β-unsaturated carbonyl coupling reaction as well as in the stoichiometric reaction of arylpalladium reagents with acrolein was studied. Excess of halide ions can effectively inhibit the β-hydride elimination of a (2-oxoalkyl)palladium intermediate, giving preferentially the protonolysis product in acidic media. This result may have further implications for the design and development of divalent palladium-catalyzed reactions

Supplementary document for Improved measurement of the glue layer in composite material by using sparse deconvolution - 6554039.pdf

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