We present the Minigrid and Miniworld libraries which provide a suite of goal-oriented 2D and 3D environments. The libraries were explicitly created with a minimalistic design paradigm to allow users to rapidly develo...
We present the Minigrid and Miniworld libraries which provide a suite of goal-oriented 2D and 3D environments. The libraries were explicitly created with a minimalistic design paradigm to allow users to rapidly develop new environments for a wide range of research-specific needs. As a result, both have received widescale adoption by the RL community, facilitating research in a wide range of areas. In this paper, we outline the design philosophy, environment details, and their world generation API. We also showcase the additional capabilities brought by the unified API between Minigrid and Miniworld through case studies on transfer learning (for both RL agents and humans) between the different observation spaces. The source code of Minigrid and Miniworld can be found at https://***/Farama-Foundation/Minigrid and https://***/Farama-Foundation/Miniworld along with their documentation at https://***/and https://***/.
The authors report the synthesis and characterization of polyimidebenzoxazoles and polyimideoxadiazoles prepared by reacting compound (1) or its acid chloride with various diamines. The thermogram of polyhydrazides an...
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The authors report the synthesis and characterization of polyimidebenzoxazoles and polyimideoxadiazoles prepared by reacting compound (1) or its acid chloride with various diamines. The thermogram of polyhydrazides and polyamides showed two main transitions. The initial weight loss below 100°C is attributed to the loss of adsorbed moisture or solvent. The weight loss above 250°C is attributed to the loss of water molecule resulting in cyclized polymer. The calculated amount of weight loss for the polymers is consistent with the observed values obtained from the thermograms, DSC thermogram did not show any melting transitions for these polymers.
Oceanographic environmental sensor technology is being investigated under the sponsorship of the Office of Naval Research and the Naval Air Warfare Center. The focus of this investigation is air-deployable, expendable...
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Oceanographic environmental sensor technology is being investigated under the sponsorship of the Office of Naval Research and the Naval Air Warfare Center. The focus of this investigation is air-deployable, expendable sensors and includes: (1) Ocean Optical Property Sensor (OOPS) designed to measure both the volume backscatter function, Beta and the diffuse attenuation coefficient, K, simultaneously; both measurements employ an LED light source for low weight and power consumption; (2) Ocean Current Profile Sensors employing Phased Array technology; (3) GPS-equipped Surface Floats for determining the ocean surface current; (4) high frequency ocean bottom sediment classifiers which use the echo information from standard ship-board fathometers to auto-classify the bottom sediment. This report gives design details of each sensor along with a description of their capabilities, packaging layouts for both moored and free-floating buoy designs, system architectures, including in-buoy data processing and control and external telemetry utilizing LEO commercial satellites. Prototype sensors have been designed, fabricated and successfully tested in a series of shallow water ocean exercises. Test results are presented and compared with conventional reference sensors to validate the sensor performance. Future sensor development plans are proposed with a view toward employing a global network of precision in-water sensors, moored and free-floating, to provide real-time data flow to the world's oceanographic community.
The mais purpose of the present paper is fo apply the fuzzy set theoretic approach to the analysis of time ***,the analysis of periodic data and the estimate of turning point of linear trend are discussed.
The mais purpose of the present paper is fo apply the fuzzy set theoretic approach to the analysis of time ***,the analysis of periodic data and the estimate of turning point of linear trend are discussed.
Pavement preservation involves minimizing the destructive impact of climate and traffic by the regular or intermittent timely application of remedial treatments to the pavement. Pavement preservation system should inc...
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Pavement preservation involves minimizing the destructive impact of climate and traffic by the regular or intermittent timely application of remedial treatments to the pavement. Pavement preservation system should include: pavement management system (PMS);long-term network planning;optimization;cost-effective decision making;and sustainable financing. Objective measurement of pavement performance is required to determine the appropriate treatment. Preventive treatment of asphalt pavements used in Ontario include: crack sealing;crack filling;fog seals and rejuvenating seals;chip seals;slurry seal;cape seal;microsurfacing;non-structural HMA overlay;surface milling and non-structural overlay;cold in-place surface recycling;and hot in-place HMA recycling. Emerging technologies include Nova Chip and Metro MatTM, for instance. This paper first discusses the traditional mindset of many road authorities and how it cannot handle the current needs of road users and the growing concerns of scarce maintenance budget. Next, the concept of pavement preservation is introduced, as well as what separates it from common preventive maintenance practices. A short review of the current preventive treatments used in Ontario is then provided. Examples of successful pavement preservation adopted by municipalities and road authorities in Ontario and in the US are also given. The paper concludes by discussing the issue of how road authorities can move forward with this correct approach.
We propose a novel scheme to realize broadband polarization conversion in optical spectral range. A polarization conversion metamaterial is designed using anisotropic metal rods placed on top of a metal film with a di...
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We present two tight-binding linear muffin-tin orbitals (TB-LMTO) techniques for electronic structure calculations of extended defects (such as grain boundaries, interphase interfaces, surface layers etc.) in metals. ...
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ISBN:
(纸本)1558993967
We present two tight-binding linear muffin-tin orbitals (TB-LMTO) techniques for electronic structure calculations of extended defects (such as grain boundaries, interphase interfaces, surface layers etc.) in metals. The first is based on the first-principles self-consistent surface Green's function approach within the atomic-sphere approximation (ASA) utilizing two-dimensional periodicity in the layers parallel to the interface. In the second approach the Hamiltonian is constructed within the TB-LMTO-ASA as well, but semiempirical terms are employed to characterize the repulsive part of the interaction and the effect of electrons in interstitial space. While the adjustable parameters have only been fitted to the properties of ideal ground state structure, the semiempirical approach describes correctly the structural energy differences, phonon frequencies etc. Two examples are presented: the electronic structure of the Sigma = 5(210)/[001] tilt grain boundary in tungsten is determined and the sensitivity of 4d magnetic moments in thin films to local environment is discussed. A comparison of the semiempirical TB-LMTO-ASA with the first-principles full-potential LMTO results is performed along the trigonal deformation path connecting the bcc, simple cubic and fee structures and the applicability of the semiempirical approach for simulating atomic structure of extended defects is assessed.
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