Discovering Evolutionary Stepping Stones through Behavior Domination

Behavior domination is proposed as a tool for understanding and harnessing the power of evolutionary systems to discover and exploit useful stepping stones. Novelty search has shown promise in overcoming deception by collecting diverse stepping stones, and several algorithms have been proposed that combine novelty with a more traditional fitness measure to refocus search and help novelty search scale to more complex domains. However, combinations of novelty and fitness do not necessarily preserve the stepping stone discovery that novelty search affords. In several existing methods, competition between solutions can lead to an unintended loss of diversity. Behavior domination defines a class of algorithms that avoid this problem, while inheriting theoretical guarantees from multiobjective optimization. Several existing algorithms are shown to be in this class, and a new algorithm is introduced based on fast non-dominated sorting. Experimental results show that this algorithm outperforms existing approaches in domains that contain useful stepping stones, and its advantage is sustained with scale. The conclusion is that behavior domination can help illuminate the complex dynamics of behavior-driven search, and can thus lead to the design of more scalable and robust algorithms.Comment: To Appear in Proceedings of the Genetic and Evolutionary Computation Conference (GECCO 2017

Researcher's guide to the NASA Ames Flight Simulator for Advanced Aircraft (FSAA)

Performance, limitations, supporting software, and current checkout and operating procedures are presented for the flight simulator, in terms useful to the researcher who intends to use it. Suggestions to help the researcher prepare the experimental plan are also given. The FSAA's central computer, cockpit, and visual and motion systems are addressed individually but their interaction is considered as well. Data required, available options, user responsibilities, and occupancy procedures are given in a form that facilitates the initial communication required with the NASA operations' group

Separator development for a heat sterilizable battery Final summary progress report, 1 May 1966 - 15 Mar. 1967

Development and testing of vivyl polymer separator materials for sterilized silver-zinc secondary batter

Reactive Quenching Of Od A (2)Σ(+) By H-2: Translational Energy Distributions For H- And D-Atom Product Channels

The H- and D-atom products from collisional quenching of OD A (2)Sigma(+) by H-2 are characterized through Doppler spectroscopy using two-photon (2 S-2 \u3c-\u3c- 1 S-2) laser-induced fluorescence. Partial deuteration enables separation of the channel forming H + HOD products, which accounts for 75% of reactive quenching events, from the D + H2O product channel. The Doppler profiles, along with those reported previously for other isotopic variants, are transformed into product translational energy distributions using a robust fitting procedure based on discrete velocity basis functions. The product translational energy distribution for the H- atom channel is strongly peaked at low energy (below 0.5 eV) with a long tail extending to the energetic limit. By contrast, the D-atom channel exhibits a small peak at low translational energy with a distinctive secondary peak at higher translational energy (approximately 1.8 eV) before falling off to higher energy. In both cases, most of the available energy flows into internal excitation of the water products. Similar distributions are obtained upon reanalysis of D- and H- atom Doppler profiles, respectively, from reactive quenching of OH A (2)Sigma(+) by D-2. The sum of the translational energy distributions for H- and D- atom channels is remarkably similar to that obtained for OH A (2)Sigma(+) + H-2, where the two channels cannot be distinguished from one another. The product translational energy distributions from reactive quenching are compared with those obtained from a previous experiment performed at higher collision energy, quasiclassical trajectory calculations of the post-quenching dynamics, and a statistical model. (C) 2011 American Institute of Physics. [doi: 10.1063/1.3644763

Removals to Somalia in Light of the Convention against Torture: Recent Evidence from Somali Bantu Deportees

This paper presents the results of a survey of Somali Bantu deported from the United States from 2016 to 2018, to determine whether they were subjected to torture upon arrival in Somalia. Of the 20 deportees interviewed, 55 percent suffered torture at least once, with the highest percentage—66.7 percent—experienced by individuals deported in 2018. The abuse, which included kidnapping, stabbings, and beatings with truncheons and whips, meets the definition of torture under Article 3 of the Convention Against Torture. Individuals were intentionally subjected to severe pain and suffering for an unlawful purpose: ransom. Further, most of the abuse was inflicted by public officials or others acting in that capacity, primarily uniformed governmental security officials. Somali police also acquiesced to Al Shabab’s torture of Somali Bantu. These results are consistent with the extreme marginalization and mistreatment that majority clans have inflicted on the Somali Bantu since the 19th century. Given the political and military power wielded by the majority clans, and the lack of protection for the Somali Bantu, there is a high likelihood that Somali Bantu will suffer torture if deported to Somalia. This survey is additional evidence that removals of the Somali Bantu violate Article 3 of the Convention Against Torture.This paper presents the results of a survey of Somali Bantu deported from the United States from 2016 to 2018, to determine whether they were subjected to torture upon arrival in Somalia. Of the 20 deportees interviewed, 55 percent suffered torture at least once, with the highest percentage—66.7 percent—experienced by individuals deported in 2018. The abuse, which included kidnapping, stabbings, and beatings with truncheons and whips, meets the definition of torture under Article 3 of the Convention Against Torture. Individuals were intentionally subjected to severe pain and suffering for an unlawful purpose: ransom. Further, most of the abuse was inflicted by public officials or others acting in that capacity, primarily uniformed governmental security officials. Somali police also acquiesced to Al Shabab’s torture of Somali Bantu. These results are consistent with the extreme marginalization and mistreatment that majority clans have inflicted on the Somali Bantu since the 19th century. Given the political and military power wielded by the majority clans, and the lack of protection for the Somali Bantu, there is a high likelihood that Somali Bantu will suffer torture if deported to Somalia. This survey is additional evidence that removals of the Somali Bantu violate Article 3 of the Convention Against Torture

Removals to Somalia in Light of the Convention against Torture: Recent Evidence from Somali Bantu Deportees

This paper presents the results of a survey of Somali Bantu deported from the United States from 2016 to 2018, to determine whether they were subjected to torture upon arrival in Somalia. Of the 20 deportees interviewed, 55 percent suffered torture at least once, with the highest percentage—66.7 percent—experienced by individuals deported in 2018. The abuse, which included kidnapping, stabbings, and beatings with truncheons and whips, meets the definition of torture under Article 3 of the Convention Against Torture. Individuals were intentionally subjected to severe pain and suffering for an unlawful purpose: ransom. Further, most of the abuse was inflicted by public officials or others acting in that capacity, primarily uniformed governmental security officials. Somali police also acquiesced to Al Shabab’s torture of Somali Bantu. These results are consistent with the extreme marginalization and mistreatment that majority clans have inflicted on the Somali Bantu since the 19th century. Given the political and military power wielded by the majority clans, and the lack of protection for the Somali Bantu, there is a high likelihood that Somali Bantu will suffer torture if deported to Somalia. This survey is additional evidence that removals of the Somali Bantu violate Article 3 of the Convention Against Torture.This paper presents the results of a survey of Somali Bantu deported from the United States from 2016 to 2018, to determine whether they were subjected to torture upon arrival in Somalia. Of the 20 deportees interviewed, 55 percent suffered torture at least once, with the highest percentage—66.7 percent—experienced by individuals deported in 2018. The abuse, which included kidnapping, stabbings, and beatings with truncheons and whips, meets the definition of torture under Article 3 of the Convention Against Torture. Individuals were intentionally subjected to severe pain and suffering for an unlawful purpose: ransom. Further, most of the abuse was inflicted by public officials or others acting in that capacity, primarily uniformed governmental security officials. Somali police also acquiesced to Al Shabab’s torture of Somali Bantu. These results are consistent with the extreme marginalization and mistreatment that majority clans have inflicted on the Somali Bantu since the 19th century. Given the political and military power wielded by the majority clans, and the lack of protection for the Somali Bantu, there is a high likelihood that Somali Bantu will suffer torture if deported to Somalia. This survey is additional evidence that removals of the Somali Bantu violate Article 3 of the Convention Against Torture

Novelty Search in Competitive Coevolution

One of the main motivations for the use of competitive coevolution systems is their ability to capitalise on arms races between competing species to evolve increasingly sophisticated solutions. Such arms races can, however, be hard to sustain, and it has been shown that the competing species often converge prematurely to certain classes of behaviours. In this paper, we investigate if and how novelty search, an evolutionary technique driven by behavioural novelty, can overcome convergence in coevolution. We propose three methods for applying novelty search to coevolutionary systems with two species: (i) score both populations according to behavioural novelty; (ii) score one population according to novelty, and the other according to fitness; and (iii) score both populations with a combination of novelty and fitness. We evaluate the methods in a predator-prey pursuit task. Our results show that novelty-based approaches can evolve a significantly more diverse set of solutions, when compared to traditional fitness-based coevolution.Comment: To appear in 13th International Conference on Parallel Problem Solving from Nature (PPSN 2014

The Case for Learned Index Structures

Indexes are models: a B-Tree-Index can be seen as a model to map a key to the position of a record within a sorted array, a Hash-Index as a model to map a key to a position of a record within an unsorted array, and a BitMap-Index as a model to indicate if a data record exists or not. In this exploratory research paper, we start from this premise and posit that all existing index structures can be replaced with other types of models, including deep-learning models, which we term learned indexes. The key idea is that a model can learn the sort order or structure of lookup keys and use this signal to effectively predict the position or existence of records. We theoretically analyze under which conditions learned indexes outperform traditional index structures and describe the main challenges in designing learned index structures. Our initial results show, that by using neural nets we are able to outperform cache-optimized B-Trees by up to 70% in speed while saving an order-of-magnitude in memory over several real-world data sets. More importantly though, we believe that the idea of replacing core components of a data management system through learned models has far reaching implications for future systems designs and that this work just provides a glimpse of what might be possible

Development of improved semi-organic structural adhesives for elevated temperature applications Technical summary report, 1 ~JUL. 1964 - 29 ~FEB. 1968

Titanium chelate polymer adhesive formulation for aluminum joint curing in high temperature application