128 research outputs found
Extend Wave Function Collapse to Large-Scale Content Generation
Wave Function Collapse (WFC) is a widely used tile-based algorithm in
procedural content generation, including textures, objects, and scenes.
However, the current WFC algorithm and related research lack the ability to
generate commercialized large-scale or infinite content due to constraint
conflict and time complexity costs. This paper proposes a Nested WFC (N-WFC)
algorithm framework to reduce time complexity. To avoid conflict and
backtracking problems, we offer a complete and sub-complete tileset preparation
strategy, which requires only a small number of tiles to generate aperiodic and
deterministic infinite content. We also introduce the weight-brush system that
combines N-WFC and sub-complete tileset, proving its suitability for game
design. Our contribution addresses WFC's challenge in massive content
generation and provides a theoretical basis for implementing concrete games.Comment: This paper is accepted by IEEE Conference on Games 2023 (nomination
of the Best Paper Award
Observation of Active Sites for Oxygen Reduction Reaction on Nitrogen-doped Multilayer Graphene
Active sites and catalytic mechanism of nitrogen-doped graphene in oxygen
reduction reaction (ORR) have been extensively studied but are still
inconclusive, partly due to the lack of an experimental method that can detect
the active sites. It is proposed in this report that the active sites on
nitrogen-doped graphene can be determined via the examination of its chemical
composition change before and after ORR. Synchrotron-based X-ray photoelectron
spectroscopy analyses of three nitrogen-doped multilayer graphene samples
reveal that oxygen reduction intermediate OH(ads) which should chemically
attach to the active sites remains on the carbon atoms neighboring pyridinic
nitrogen after ORR. In addition, a high amount of the OH(ads) attachment after
ORR corresponds to a high catalytic efficiency and vice versa. These pinpoint
that the carbon atoms close to pyridinic nitrogen are the main active sites
among the different nitrogen doping configurations
Game-theoretic flexible-final-time differential dynamic programming using Gaussian quadrature
Dynamics and nucleation of dislocations in crystals
Hydrogen-poor superluminous supernovae (SLSNe-I) have been predominantly
found in low-metallicity, star-forming dwarf galaxies. Here we identify
Gaia17biu/SN 2017egm as an SLSN-I occurring in a "normal" spiral galaxy (NGC
3191) in terms of stellar mass (several times 10^10 M_sun) and metallicity
(roughly Solar). At redshift z=0.031, Gaia17biu is also the lowest redshift
SLSN-I to date, and the absence of a larger population of SLSNe-I in dwarf
galaxies of similar redshift suggests that metallicity is likely less important
to the production of SLSNe-I than previously believed. With the smallest
distance and highest apparent brightness for an SLSN-I, we are able to study
Gaia17biu in unprecedented detail. Its pre-peak near-ultraviolet to optical
color is similar to that of Gaia16apd and among the bluest observed for an
SLSN-I while its peak luminosity (M_g = -21 mag) is substantially lower than
Gaia16apd. Thanks to the high signal-to-noise ratios of our spectra, we
identify several new spectroscopic features that may help to probe the
properties of these enigmatic explosions. We detect polarization at the ~0.5%
level that is not strongly dependent on wavelength, suggesting a modest, global
departure from spherical symmetry. In addition, we put the tightest upper limit
yet on the radio luminosity of an SLSN-I with <5.4x10^26 erg/s/Hz (at 10 GHz),
which is almost a factor of 40 better than previous upper limits and one of the
few measured at an early stage in the evolution of an SLSN-I. This limit
largely rules out an association of this SLSNe-I with known populations of
gamma-ray burst (GRB) like central engines.Comment: Accepted for publication in ApJ. Ancillary ASCII tables added:
TRL.txt -- blackbody temperature, radius and luminosity; uvw2uvm2uvw1uvu.txt
-- UV photometry; BgVri.txt -- optical photometry; zJHK.txt -- NIR photometr
Anthropogenic Plutonium in the North Jiangsu tidal flats of the Yellow Sea in China
The 239+240Pu activities and 240Pu/239Pu atom ratios were analyzed using a double-focusing SF-ICP-MS for sediment core samples obtained in 2007-2008 from the North Jiangsu tidal flats in the Yellow Sea in China. Particular attention was focused on the 240Pu/239Pu atom ratios in the sediment to identify the origins of Pu isotopes. The profiles of 239+240Pu activities in the sediment cores are similar to those of the 137Cs activities. The 240Pu/239Pu atom ratios in the tidal flats showed typical global fallout values, indicating that this area did not receive the possible early direct close-in fallout or oceanic current transported Pu from the Pacific Proving Grounds (PPG). This is different from the sediments in the Yangtze River estuary in the East China Sea, where the PPG source Pu contributed ca. 45% to the total inventory. In addition, the observation of the global fallout origin Pu in the North Jiangsu tidal flats indicated that the nuclear power plant in the region was not causing any alteration/contamination to the 240Pu/239Pu atom ratios. The 239+240Pu and 137Cs activities/inventories in the sediment cores showed correlation to the mean clay sediment compositions (fine-particles) in the tidal flats. Therefore, mud deposits are served as sinks for the anthropogenic radionuclides in the tidal flats and the Yellow Sea. Integrated with the previously reported spatial distributions of 239+240Pu and 137Cs activities in the surface sediments of the Yellow Sea, the mechanism of Pu transport with the ocean currents and the scavenging characteristics in the Yellow Sea were discussed
135Cs determination in the environment and its application: A review
Under the background of rapid development in nuclear power, strengthen the knowledge of 135Cs analysis and application is extremely necessary. Therefore, based on published literatures and materials, the source term and instrumental analysis of 135Cs were summarized and addressed. Different chemical separation methods and mass spectrometry techniques (ICP-MS, TIMS, RIMS and AMS) for radiocesium determination were compared in this review. In addition, the obtained limit of detection and chemical yield in reported papers were also compared. Finally, we discussed the potential application of 135Cs/137Cs isotopic ratio in the environment with emphasis on Fukushima nuclear accident and prospects in accurate determination, migration behavior and application of 135Cs/137Cs isotopic ratio for future research
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