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Using program synthesis to select instructions for and optimize input programs is receiving increasing attention. However, existing synthesis-based compilers are faced by two major challenges that prohibit the deployment of program synthesis in production compilers: exorbitantly long synthesis times spanning several minutes and hours; and scalability issues that prevent synthesis of complex modern compute and data swizzle instructions, which have been found to maximize performance of modern tensor and stencil workloads. This paper proposes MISAAL, a synthesis-based compiler that employs a novel strategy to use formal semantics of hardware instructions to automatically prune a large search space of rewrite rules for modern complex instructions in an offline stage. MISAAL also proposes a novel methodology to make term-rewriting process in the online stage (at compile-time) extremely lightweight so as to enable programs to compile in seconds. Our results show that MISAAL reduces compilation times by up to a geomean of 16x compared to the state-of-the-art synthesis-based compiler, HYDRIDE. MISAAL also delivers competitive runtime performance against the production compiler for image processing and deep learning workloads, Halide, as well as HYDRIDE across x86, Hexagon and ARM. 

California’s agricultural workers are a vulnerable population due to their undocumented status and poor working conditions. This paper describes community engagement with NGO workers, farm laborers, and farm owners to identify and address the effects of climate change, namely heat stress, on, strawberry field workers. We deployed personal informatics devices in a longitudinal study with three field workers for a month and a half and presented the collected statistics back to them, asking them to reflect on their personal health (e.g., exposure to heat stress) and work data. We found that field workers normalized grit - the irregularity, adversity, competitiveness, and helplessness of their labor - thereby limiting the promise of personal informatics to help users lead healthier lives. Implicitly, personal informatics supports white collar workers such as information workers; overall, however, our study suggests a mismatch between current designs and front-line work which involve intensive physical work requirements. 

Abstract Many planets in the solar system and across the Galaxy have hydrogen-rich atmospheres overlying more heavy element-rich interiors with which they interact for billions of years. Atmosphere–interior interactions are thus crucial to understanding the formation and evolution of these bodies. However, this understanding is still lacking in part because the relevant pressure–temperature conditions are extreme. We conduct molecular dynamics simulations based on density functional theory to investigate how hydrogen and water interact over a wide range of pressure and temperature, encompassing the interiors of Neptune-sized and smaller planets. We determine the critical curve at which a single homogeneous phase exsolves into two separate hydrogen-rich and water-rich phases, finding good agreement with existing experimental data. We find that the temperature along the critical curve increases with increasing pressure and shows the influence of a change in fluid structure from molecular to atomic near 30 GPa and 3000 K, which may impact magnetic field generation. The internal temperatures of many exoplanets, including TOI-270 d and K2-18 b, may lie entirely above the critical curve: the envelope is expected to consist of a single homogeneous hydrogen–water fluid, which is much less susceptible to atmospheric loss as compared with a pure hydrogen envelope. As planets cool, they cross the critical curve, leading to rainout of water-rich fluid and an increase in internal luminosity. Compositions of the resulting outer, hydrogen-rich and inner, water-rich envelopes depend on age and instellation and are governed by thermodynamics. Rainout of water may be occurring in Uranus and Neptune at present. 

Abstract We provide a uniform bound on the partial sums of multiplicative functions under very general hypotheses. As an application, we give a nearly optimal estimate for the count of$$n \le x$$for which the Alladi–Erdős function$$A(n) = \sum_{p^k \parallel n} k p$$takes values in a given residue class moduloq, whereqvaries uniformly up to a fixed power of$$\log x$$. We establish a similar result for the equidistribution of the Euler totient function$$\phi(n)$$among the coprime residues to the ‘correct’ moduliqthat vary uniformly in a similar range and also quantify the failure of equidistribution of the values of$$\phi(n)$$among the coprime residue classes to the ‘incorrect’ moduli. 

Currently, the rapidly growing population is producing hazardous waste materials at an unprecedented rate, which seriously affects the global environment. Additionally, increasing population and pollution have amplified the need for renewable energy and efficient energy-storage technologies. One strategy is to implement greener processes for efficiency and/or utilize the waste generated for useful domestic and industrial applications. In this context, here, we harnessed the most littered environmental pollutant, cigarette filter waste (CFW), to synthesize carbon nanomaterials (CNM) via a single-step pyrolysis process, devoid of any catalyst or activating agent, possessing optimal characteristics for serving as an active electrode material in the fabrication of cutting-edge supercapacitors, thereby addressing the issue of waste recycling and the need for energy storage devices among the populace. Supercapacitors, namely SC-1 to SC-4 matching electrolytes, 1M H2SO4, 2M H2SO4, 1M KOH, and 2M KOH, fabricated using CNM electrodes were evaluated. Among these, SC-2 exhibits superior performance, demonstrating a remarkable capacitance of 240 Fg–1 at low scan rates (2 mVs–1), an enhanced energy density (22.4 Whkg–1), and commendable power density (399.43 Wkg–1). Furthermore, SC-2 maintained 5000 cycles of outstanding stability with 97.8% capacitance retention. This study unveils the potential of CFW-derived CNMs as an electrode material for the realization of state-of-the-art supercapacitors.