Deep Ordinal Reinforcement Learning

Reinforcement learning usually makes use of numerical rewards, which have nice properties but also come with drawbacks and difficulties. Using rewards on an ordinal scale (ordinal rewards) is an alternative to numerical rewards that has received more attention in recent years. In this paper, a general approach to adapting reinforcement learning problems to the use of ordinal rewards is presented and motivated. We show how to convert common reinforcement learning algorithms to an ordinal variation by the example of Q-learning and introduce Ordinal Deep Q-Networks, which adapt deep reinforcement learning to ordinal rewards. Additionally, we run evaluations on problems provided by the OpenAI Gym framework, showing that our ordinal variants exhibit a performance that is comparable to the numerical variations for a number of problems. We also give first evidence that our ordinal variant is able to produce better results for problems with less engineered and simpler-to-design reward signals.Comment: replaced figures for better visibility, added github repository, more details about source of experimental results, updated target value calculation for standard and ordinal Deep Q-Networ

3-5-man chess: Maximals and mzugs

This article reports the combined results of several initiatives in creating and surveying complete suites of endgame tables (EGTs) to the Depth to Mate (DTM) and Depth to Conversion (DTC) metrics. Data on percentage results, maximals and mutual zugzwangs, mzugs, has been filed and made available on the web, as have the DTM EGTs

A Search for X-Ray Bright Distant Clusters of Galaxies

We present the results of a search for X--ray luminous distant clusters of galaxies. We found extended X--ray emission characteristic of a cluster towards two of our candidate clusters of galaxies. They both have a luminosity in the ROSAT bandpass of $\simeq10^{44}{\rm \,erg\,s^{-1}}$ and a redshift of $>0.5$; thus making them two of the most distant X--ray clusters ever observed. Furthermore, we show that both clusters are optically rich and have a known radio source associated with them. We compare our result with other recent searches for distant X--ray luminous clusters and present a lower limit of $1.2\times10^{-7}\,{\rm Mpc^{-3}}$ for the number density of such high redshift clusters. This limit is consistent with the expected abundance of such clusters in a standard (b=2) Cold Dark Matter Universe. Finally, our clusters provide important high redshift targets for further study into the origin and evolution of massive clusters of galaxies. Accepted for publication in the 10th September 1994 issue of ApJ.Comment: 20 pages Latex file + 1 postscript figure file appende

Lifshitz transitions and quasiparticle de-renormalization in YbRh2_2Si2_2

We study the effect of magnetic fields up to 15 T on the heavy fermion state of YbRh$_2$Si$_2$ via Hall effect and magnetoresistance measurements down to 50 mK. Our data show anomalies at three different characteristic fields. We compare our data to renormalized band structure calculations through which we identify Lifshitz transitions associated with the heavy fermion bands. The Hall measurements indicate that the de-renormalization of the quasiparticles, {\it i.e} the destruction of the local Kondo singlets, occurs smoothly while the Lifshitz transitions occur within rather confined regions of the magnetic field.Comment: 7 pages, 5 figure

A metasynthesis of studies of patients’ experience of living with terminal cancer

Objective: The aim of this research was to produce a synthesis of phenomenological studies of the experience of living with the awareness of having terminal cancer in order to gain a more complete understanding of the parameters of this experience. Methods: This research used metasynthesis as a method for integrating the results of 23 phenomenological studies of the experience of living with the awareness of having terminal cancer published between 2011 and 2016. Results: The metasynthesis generated 19 theme clusters which informed the construction of four master themes: trauma, liminality, holding on to life and life as a cancer patient. Each master theme captures a distinct experiential dimension of living with the awareness of having terminal cancer. Each dimension brings with it significant and distinctive psychological challenges. Conclusion: The results from the present metasynthesis suggest that the experience of living with the awareness of having terminal cancer is a multi-dimensional experience which patients actively negotiate as they search for ways in which they can rise to the psychological challenges associated with it. A better understanding of the parameters of this experience can help health care professionals provide appropriate support for this client group

Interaction-induced chiral p_x \pm i p_y superfluid order of bosons in an optical lattice

The study of superconductivity with unconventional order is complicated in condensed matter systems by their extensive complexity. Optical lattices with their exceptional precision and control allow one to emulate superfluidity avoiding many of the complications of condensed matter. A promising approach to realize unconventional superfluid order is to employ orbital degrees of freedom in higher Bloch bands. In recent work, indications were found that bosons condensed in the second band of an optical chequerboard lattice might exhibit p_x \pm i p_y order. Here we present experiments, which provide strong evidence for the emergence of p_x \pm i p_y order driven by the interaction in the local p-orbitals. We compare our observations with a multi-band Hubbard model and find excellent quantitative agreement

Observation of Landau quantization and standing waves in HfSiS

Recently, HfSiS was found to be a new type of Dirac semimetal with a line of Dirac nodes in the band structure. Meanwhile, Rashba-split surface states are also pronounced in this compound. Here we report a systematic study of HfSiS by scanning tunneling microscopy/spectroscopy at low temperature and high magnetic field. The Rashba-split surface states are characterized by measuring Landau quantization and standing waves, which reveal a quasi-linear dispersive band structure. First-principles calculations based on density-functional theory are conducted and compared with the experimental results. Based on these investigations, the properties of the Rashba-split surface states and their interplay with defects and collective modes are discussed.Comment: 6 pages, 5 figure

Court Summons, June 20, 1883

Court order summoning William Kiefer to the Court of Common Pleas in Franklin County on June 21, 1883 along with Chas W. Miller and J. B. Cornell by Deputy R. C. Wirth.https://digitalcommons.otterbein.edu/cornell_ephemera/1129/thumbnail.jp

Court Summons, June 20, 1883

Court order summoning George B Strait to the Court of Common Pleas of Franklin County by Deputy R. C. Wirth alongside plaintiff Chas. W. Miller and Defendant John B. Cornell on June 21, 1883.https://digitalcommons.otterbein.edu/cornell_ephemera/1130/thumbnail.jp