Timing-Driven Macro Placement

Placement is an important step in the process of finding physical layouts for electronic computer chips. The basic task during placement is to arrange the building blocks of the chip, the circuits, disjointly within a given chip area. Furthermore, such positions should result in short circuit interconnections which can be routed easily and which ensure all signals arrive in time. This dissertation mostly focuses on macros, the largest circuits on a chip. In order to optimize timing characteristics during macro placement, we propose a new optimistic timing model based on geometric distance constraints. This model can be computed and evaluated efficiently in order to predict timing traits accurately in practice. Packing rectangles disjointly remains strongly NP-hard under slack maximization in our timing model. Despite of this we develop an exact, linear time algorithm for special cases. The proposed timing model is incorporated into BonnMacro, the macro placement component of the BonnTools physical design optimization suite developed at the Research Institute for Discrete Mathematics. Using efficient formulations as mixed-integer programs we can legalize macros locally while optimizing timing. This results in the first timing-aware macro placement tool. In addition, we provide multiple enhancements for the partitioning-based standard circuit placement algorithm BonnPlace. We find a model of partitioning as minimum-cost flow problem that is provably as small as possible using which we can avoid running time intensive instances. Moreover we propose the new global placement flow Self-Stabilizing BonnPlace. This approach combines BonnPlace with a force-directed placement framework. It provides the flexibility to optimize the two involved objectives, routability and timing, directly during placement. The performance of our placement tools is confirmed on a large variety of academic benchmarks as well as real-world designs provided by our industrial partner IBM. We reduce running time of partitioning significantly and demonstrate that Self-Stabilizing BonnPlace finds easily routable placements for challenging designs – even when simultaneously optimizing timing objectives. BonnMacro and Self-Stabilizing BonnPlace can be combined to the first timing-driven mixed-size placement flow. This combination often finds placements with competitive timing traits and even outperforms solutions that have been determined manually by experienced designers

Examining the impact of heterogeneous nitryl chloride production on air quality across the United States

The heterogeneous hydrolysis of dinitrogen pentoxide (N₂O₅) has typically been modeled as only producing nitric acid. However, recent field studies have confirmed that the presence of particulate chloride alters the reaction product to produce nitryl chloride (ClNO₂) which undergoes photolysis to generate chlorine atoms and nitrogen dioxide (NO₂). Both chlorine and NO₂ affect atmospheric chemistry and air quality. We present an updated gas-phase chlorine mechanism that can be combined with the Carbon Bond 05 mechanism and incorporate the combined mechanism into the Community Multiscale Air Quality (CMAQ) modeling system. We then update the current model treatment of heterogeneous hydrolysis of N₂O₅ to include ClNO₂ as a product. The model, in combination with a comprehensive inventory of chlorine compounds, reactive nitrogen, particulate matter, and organic compounds, is used to evaluate the impact of the heterogeneous ClNO₂ production on air quality across the United States for the months of February and September in 2006. The heterogeneous production increases ClNO₂ in coastal as well as many in-land areas in the United States. Particulate chloride derived from sea-salts, anthropogenic sources, and forest fires activates the heterogeneous production of ClNO₂. With current estimates of tropospheric emissions, it modestly enhances monthly mean 8-h ozone (up to 1–2 ppbv or 3–4%) but causes large increases (up to 13 ppbv) in isolated episodes. This chemistry also substantially reduces the mean total nitrate by up to 0.8–2.0 μg m⁻³ or 11–21%. Modeled ClNO₂ accounts for up to 6% of the monthly mean total reactive nitrogen. Sensitivity results of the model suggest that heterogeneous production of ClNO₂ can further increase O₃ and reduce TNO₃ if elevated particulate-chloride levels are present in the atmosphere

Development of an extended chemical mechanism for global–through–urban applications

AbstractThe interactions between climate and air quality are receiving increasing attention due to their high relevancy to climate change. Coupled climate and air quality models are being developed to study these interactions. These models need to address the transport and chemistry of atmospheric species over a large range of scales and atmospheric conditions. In particular, the chemistry mechanism is a key component of such models because it needs to include the relevant reactions to simulate the chemistry of the lower troposphere, the upper troposphere, and the lower stratosphere, as well as the chemistry of polluted, rural, clean, and marine environments. This paper describes the extension of an existing chemistry mechanism for urban/regional applications, the 2005 version of the Carbon Bond Mechanism (CB05), to include the relevant atmospheric chemistry for global and global–through–urban applications. Updates to the mechanism include the most important gas–phase reactions needed for the lower stratosphere as well as reactions involving mercury species, and a number of heterogeneous reactions on aerosol particles, cloud droplets, and Polar Stratospheric Clouds (PSCs). The extended mechanism, referred to as CB05 for Global Extension (CB05_GE), is tested for a range of atmospheric conditions using a zero–dimensional box–model. A comparison of results from the extended mechanism with those from the original starting mechanism for both clean and polluted conditions in the lower troposphere shows that the extended mechanism preserves the fidelity of the original mechanism under those conditions. Simulations of marine Arctic conditions, upper tropospheric conditions, and lower stratospheric conditions with the box model illustrate the importance of halogen chemistry and heterogeneous reactions (on aerosol surfaces as well as PSCs for stratospheric conditions) for predicting ozone and elemental mercury depletion events that are often observed during these conditions. Depletions that are comparable to observed depletions are predicted by the box model for very clean conditions (extremely low or zero concentrations of aldehydes and other VOCs) because, in the absence of continuous sources of active halogens, these conditions result in less conversion of active chlorine and bromine to more stable products, such as HCl and HBr

Dangerous Decor: Consumer Knowledge of Health Risks within Interior Spaces

Interior décor is an ever-present part of people\u27s daily lives. The furnishings and finishes with which people surround themselves are part of their personal expression, but these components in people\u27s homes and work spaces can negatively affect their health. Products such as furniture and paints can contain harmful chemicals, including volatile organic compounds (VOCs) so toxic they are pollutants regulated by the U.S. Environmental Protection Agency. With the rise in the green movement, healthy and environmentally safe alternatives such as low or zero-VOC paints are becoming more available. This study assessed how aware consumers and design professionals are of environmentally safe products, especially paints low in toxic VOCs. A survey was administered to 160 randomly chosen consumers at four Kelly-Moore retail paint stores in San Jose, California, to determine public awareness of and willingness to purchase low-VOC paints. In addition, 27 design professionals from interior design and architecture firms in San Jose were surveyed to assess their knowledge of and willingness to recommend healthy and environmentally safe products to their clients. The findings of this study provide insight into the factors that promote or hinder the use of healthy home furnishing products by the public and design professionals as well as provide suggestions for promoting the purchase of green products

Proactive Aging Mitigation in CGRAs through Utilization-Aware Allocation

Resource balancing has been effectively used to mitigate the long-term aging effects of Negative Bias Temperature Instability (NBTI) in multi-core and Graphics Processing Unit (GPU) architectures. In this work, we investigate this strategy in Coarse-Grained Reconfigurable Arrays (CGRAs) with a novel application-to-CGRA allocation approach. By introducing important extensions to the reconfiguration logic and the datapath, we enable the dynamic movement of configurations throughout the fabric and allow overutilized Functional Units (FUs) to recover from stress-induced NBTI aging. Implementing the approach in a resource-constrained state-of-the-art CGRA reveals $2.2\times$ lifetime improvement with negligible performance overheads and less than $10\%$ increase in area.Comment: Please cite this as: M. Brandalero, B. N. Lignati, A. Carlos Schneider Beck, M. Shafique and M. H\"ubner, "Proactive Aging Mitigation in CGRAs through Utilization-Aware Allocation," 2020 57th ACM/IEEE Design Automation Conference (DAC), San Francisco, CA, USA, 2020, pp. 1-6, doi: 10.1109/DAC18072.2020.921858

Narcissism and the strategic pursuit of short-term mating : universal links across 11 world regions of the International Sexuality Description Project-2.

Previous studies have documented links between sub-clinical narcissism and the active pursuit of short-term mating strategies (e.g., unrestricted sociosexuality, marital infidelity, mate poaching). Nearly all of these investigations have relied solely on samples from Western cultures. In the current study, responses from a cross-cultural survey of 30,470 people across 53 nations spanning 11 world regions (North America, Central/South America, Northern Europe, Western Europe, Eastern Europe, Southern Europe, Middle East, Africa, Oceania, Southeast Asia, and East Asia) were used to evaluate whether narcissism (as measured by the Narcissistic Personality Inventory; NPI) was universally associated with short-term mating. Results revealed narcissism scores (including two broad factors and seven traditional facets as measured by the NPI) were functionally equivalent across cultures, reliably associating with key sexual outcomes (e.g., more active pursuit of short-term mating, intimate partner violence, and sexual aggression) and sex-related personality traits (e.g., higher extraversion and openness to experience). Whereas some features of personality (e.g., subjective well-being) were universally associated with socially adaptive facets of Narcissism (e.g., self-sufficiency), most indicators of short-term mating (e.g., unrestricted sociosexuality and marital infidelity) were universally associated with the socially maladaptive facets of narcissism (e.g., exploitativeness). Discussion addresses limitations of these cross-culturally universal findings and presents suggestions for future research into revealing the precise psychological features of narcissism that facilitate the strategic pursuit of short-term mating

Deterministic Parallel Hypergraph Partitioning

Balanced hypergraph partitioning is a classical NP-hard optimization problem with applications in various domains such as VLSI design, simulating quantum circuits, optimizing data placement in distributed databases or minimizing communication volume in high-performance computing. Engineering parallel heuristics for this problem is a topic of recent research. Most of them are non-deterministic though. In this work, we design and implement a highly scalable deterministic algorithm in the state-of-the-art parallel partitioning framework Mt-KaHyPar. On our extensive set of benchmark instances, it achieves similar partition quality and performance as a comparable but non-deterministic configuration of Mt-KaHyPar and outperforms the only other existing parallel deterministic algorithm BiPart regarding partition quality, running time and parallel speedups

Pulses and likelihood of Fúquene Lagoon flood occurrence

1 recurso electrónico (páginas 45-56).La laguna de Fúquene en los últimos 20 años de manera reiterada ha sido afecta por eventos de inundación. Ante dicha afectación se han visto perjudicadas poblaciones aledañas a la Laguna, adicional causa alteraciones a la biodiversidad y ecosistema de la misma. Con el amino de estudiar los eventos de inundación históricos de la Laguna se evaluaran los registros diarios de los niveles de agua de la Laguna de Fúquene. A partir del análisis de dichos niveles de agua históricos se hayo los pulsos de inundación históricos, frecuencia de inundación, probabilidad de permanecía de la inundación. Se detectó que los niveles más altos de la Laguna coinciden con las épocas de invierno de la región, las cuales son Abril, Mayo, Junio, Julio, Noviembre y Diciembre. Los niveles históricos más altos se presentaron en los años 2006, 2010, 2011 y 2012. Dicha información se provee con el objetivo de orientar a la comunidad aledaña a la laguna o tomador de decisiones (entidades pertinentes) al conocer cuándo y duración de una eventual inundación y a partir de ello, generar los planes de contingencia y ordenamiento territorial.The Lagoon of Fuquene has been repeatedly affected for flood events in the last 20 years. Due to this affectation, populations adjacent to the lagoon have been harmed, causing additional alterations to the biodiversity and ecosystem. With the purpose of studying the historical flood events of the lagoon, the daily records of the water levels of the lagoon of Fuquene will be evaluated. Based on that analysis, the historical flood pulses, flood frequency, flood probability of permanence was found. It was detected that the highest levels in the lagoon coincide with the winter seasons, which are April, May, June, July, November and December. The highest historical levels were presented in 2006, 2010, 2011 y 2012. This information is provided with the objective of guiding the nearby community of the lagoon or decision maker (relevant entities) to know when and duration of a possible flood, and to allow generate contingency plans and land use planning.Bibliografía y webgrafía: página 56