- 标题
- 摘要
- 关键词
- 实验方案
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Crystal size improvement of Bi-based superconducting whiskers under stress-controlled condition
摘要: Using stress-controlled amorphous precursors, we have successfully grown Bi2Sr2Ca n-1CunOy (Bi-based) high-transition temperature superconducting whiskers with large crystal-size. Especially, under a high compressive stress attained by 1 GPa pelletizing, the crystal size of a whisker was significantly enhanced up to 9.5 mm length (growth period: 96 h) which is 2.4 times larger than that of the conventional amorphous-precursors method when using similar growth conditions and substrate compositions. In addition, by using the stress-controlled precursors, the number of the obtained Bi-based whiskers were also increased by a factor of 1.8.
关键词: A2. Single crystal growth,A1. Stresses,B2. Superconducting materials,A1. Growth models
更新于2025-09-23 15:19:57
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[IEEE 2019 21st International Conference on Transparent Optical Networks (ICTON) - Angers, France (2019.7.9-2019.7.13)] 2019 21st International Conference on Transparent Optical Networks (ICTON) - Si and Si-Rich Silicon-Nitride Waveguides for Optical Transmissions and Nonlinear Applications Around 2 ??m
摘要: Grasping and manipulating everyday objects in a goal-directed manner is an important ability of a service robot. The robot needs to reason about task requirements and ground these in the sensorimotor information. Grasping and interaction with objects are challenging in real-world scenarios, where sensorimotor uncertainty is prevalent. This paper presents a probabilistic framework for the representation and modeling of robot-grasping tasks. The framework consists of Gaussian mixture models for generic data discretization, and discrete Bayesian networks for encoding the probabilistic relations among various task-relevant variables, including object and action features as well as task constraints. We evaluate the framework using a grasp database generated in a simulated environment including a human and two robot hand models. The generative modeling approach allows the prediction of grasping tasks given uncertain sensory data, as well as object and grasp selection in a task-oriented manner. Furthermore, the graphical model framework provides insights into dependencies between variables and features relevant for object grasping.
关键词: grasping,Cognitive human–robot interaction,recognition,learning and adaptive systems,probabilistic graphical models
更新于2025-09-23 15:19:57
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[IEEE 2019 International Conference on Microwave and Millimeter Wave Technology (ICMMT) - Guangzhou, China (2019.5.19-2019.5.22)] 2019 International Conference on Microwave and Millimeter Wave Technology (ICMMT) - A 300-GHz Injection-Locking Coupled Terahertz Voltage-Controlled Oscillator in 40-nm CMOS Process
摘要: Building models are a valuable information source for urban studies and in particular for analyses of urban mass concentrations (UMCS). Most commonly, light detection and ranging (LiDAR) is used for their generation. The trade-off for the high geometric detail of these data is the low spatial coverage, comparably high costs and low actualization rates. Spaceborne stereo data from Cartosat-1 are able to cover large areas on the one hand, but hold a lower geometric resolution on the other hand. In this paper, we investigate to which extent the geometric shortcomings of Cartosat-1 can be overcome integrating building footprints from topographic maps for the derivation of large-area building models. Therefore, we describe the methodology to derive digital surface models (DSMs) from Cartosat-1 data and the derivation of building footprints from topographic maps at 1:25 000 (DTK-25). Both data are fused to generate building block models for four metropolitan regions in Germany with an area of ~ 16 000 km2. Building block models are further aggregated to 1 × 1 km grid cells and volume densities are computed. Volume densities are classi?ed to various levels of UMCs. Performance evaluation of the building block models reveals that the building footprints are larger in the DTK-25, and building heights are lower with a mean absolute error of 3.21 m. Both factors in?uence the building volume, which is linearly lower than the reference. However, this error does not affect the classi?cation of UMC, which can be classi?ed with accuracies between 77% and 97%.
关键词: digital elevation models,topographic maps,cartosat,Building model
更新于2025-09-23 15:19:57
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Enhanced Thermally Tunable Optical Filter and its Applications in Erbium-Doped Fiber Lasers
摘要: We present a method for the automatic localization of facial landmarks that integrates nonrigid deformation with the ability to handle missing points. The algorithm generates sets of candidate locations from feature detectors and performs combinatorial search constrained by a flexible shape model. A key assumption of our approach is that for some landmarks there might not be an accurate candidate in the input set. This is tackled by detecting partial subsets of landmarks and inferring those that are missing, so that the probability of the flexible model is maximized. The ability of the model to work with incomplete information makes it possible to limit the number of candidates that need to be retained, drastically reducing the number of combinations to be tested with respect to the alternative of trying to always detect the complete set of landmarks. We demonstrate the accuracy of the proposed method in the face recognition grand challenge database, where we obtain average errors of approximately 3.5 mm when targeting 14 prominent facial landmarks. For the majority of these our method produces the most accurate results reported to date in this database. Handling of occlusions and surfaces with missing parts is demonstrated with tests on the Bosphorus database, where we achieve an overall error of 4.81 and 4.25 mm for data with and without occlusions, respectively. To investigate potential limits in the accuracy that could be reached, we also report experiments on a database of 144 facial scans acquired in the context of clinical research, with manual annotations performed by experts, where we obtain an overall error of 2.3 mm, with averages per landmark below 3.4 mm for all 14 targeted points and within 2 mm for half of them. The coordinates of automatically located landmarks are made available on-line.
关键词: statistical shape models,craniofacial anthropometry,geometric features,3-D facial landmarks
更新于2025-09-23 15:19:57
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Enhanced Efficiency and Stability of Inverted Planar Perovskite Solar Cells With Piperazine as an Efficient Dopant Into PCBM
摘要: Large-scale human motion databases are key for research questions ranging from human motion analysis and synthesis, biomechanics of human motion, data-driven learning of motion primitives, and rehabilitation robotics to the design of humanoid robots and wearable robots such as exoskeletons. In this paper we present a large-scale database of whole-body human motion with methods and tools, which allows a unifying representation of captured human motion, and efficient search in the database, as well as the transfer of subject-specific motions to robots with different embodiments. To this end, captured subject-specific motion is normalized regarding the subject’s height and weight by using a reference kinematics and dynamics model of the human body, the master motor map (MMM). In contrast with previous approaches and human motion databases, the motion data in our database consider not only the motions of the human subject but the position and motion of objects with which the subject is interacting as well. In addition to the description of the MMM reference model, we present procedures and techniques for the systematic recording, labeling, and organization of human motion capture data, object motions as well as the subject–object relations. To allow efficient search for certain motion types in the database, motion recordings are manually annotated with motion description tags organized in a tree structure. We demonstrate the transfer of human motion to humanoid robots and provide several examples of motion analysis using the database.
关键词: whole-body human motion databases,models of the human body,Humanoid robots
更新于2025-09-23 15:19:57
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Accuracy and reliability of measurements performed using two different software programs on digital models generated using laser and computed tomography plaster model scanners
摘要: Objective: The aim of this study was to compare the accuracy and reliability of measurements performed using two different software programs on digital models generated using two types of plaster model scanners (a laser scanner and a computed tomography [CT] scanner). Methods: Thirty plaster models were scanned with a 3Shape laser scanner and with a Flash CT scanner. Two examiners performed measurements on plaster models by using digital calipers and on digital models by using Ortho Analyzer (3Shape) and Digimodel? (OrthoProof) software programs. Forty-two measurements, including tooth diameter, crown height, overjet, overbite, intercanine and intermolar distances, and sagittal relationship, were obtained. Results: Statistically significant differences were not found between the plaster and digital model measurements (ANOVA); however, some discrepancies were clinically relevant. Plaster and digital model measurements made using the two scanning methods showed high intraclass coefficient correlation values and acceptable 95% limits of agreement in the Bland-Altman analysis. The software used did not influence the accuracy of measurements. Conclusions: Digital models generated from plaster casts by using laser and CT scanning and measured using two different software programs are accurate, and the measurements are reliable. Therefore, both fabrication methods and software could be used interchangeably.
关键词: Computed tomography,Three-dimensional diagnosis and treatment planning,Digital models,Three-dimensional scanner
更新于2025-09-23 15:19:57
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Remote Spatio-Temporal Focusing over Multimode Fiber Enabled by Single-Ended Channel Estimation
摘要: Interest in deep probabilistic graphical models has increased in recent years, due to their state-of-the-art performance on many machine learning applications. Such models are typically trained with the stochastic gradient method, which can take a significant number of iterations to converge. Since the computational cost of gradient estimation is prohibitive even for modestly sized models, training becomes slow and practically usable models are kept small. In this paper we propose a new, largely tuning-free algorithm to address this problem. Our approach derives novel majorization bounds based on the Schatten- norm. Intriguingly, the minimizers of these bounds can be interpreted as gradient methods in a non-Euclidean space. We thus propose using a stochastic gradient method in non-Euclidean space. We both provide simple conditions under which our algorithm is guaranteed to converge, and demonstrate empirically that our algorithm leads to dramatically faster training and improved predictive ability compared to stochastic gradient descent for both directed and undirected graphical models.
关键词: Monte Carlo simulation methods,graphical models,Boltzmann distributions,Gradient methods,maximum likelihood estimation
更新于2025-09-23 15:19:57
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Photovoltaic power forecast using empirical models and artificial intelligence approaches for water pumping systems
摘要: The solar water pumping system is one of the brightest applications of solar energy for its environmental and economic advantages. It consists of a photovoltaic panel which converts solar energy into electrical energy to operate a DC or AC motor and a battery bank. The photovoltaic power fluctuation can affect the water pumping system performances. Thus, the photovoltaic power prediction is very important to ensure a balance between the produced energy and the pump requirements. The prediction of the generated power depends on solar irradiation and ambient temperature forecasting. The purpose of this study was to evaluate various methodologies for weather data estimation namely: the empirical models, the feed forward neural network and the adaptive neuro-fuzzy inference system. The simulation results show that the ANFIS model can be successfully used to forecast the photovoltaic power. The predicted energy was used for the solar water pumping management algorithm.
关键词: water pumping system management,photovoltaic power,empirical models,forecast,artificial neural network,neuro fuzzy inference system
更新于2025-09-23 15:19:57
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A Waveguide-Fed 35-GHz Rectifier With High Conversion Efficiency
摘要: Raman spectroscopy performed using optical fibers, with excitation at 1064 nm and a dispersive detection scheme, was utilized to measure a selection of unifloral honeys produced in the Italian region of Calabria. The honey samples had three different botanical origins: chestnut, citrus, and acacia. A multivariate processing of the spectroscopic data enabled us to distinguish their botanical origin, and to build predictive models for quantifying important nutraceutic indicators, such as the main sugars and potassium. Furthermore, the Raman spectra of chestnut honeys were compared with the taste profile measured by an electronic tongue: A good correlation to a bitter-savory taste was obtained. This experiment indicates the excellent potential of Raman spectroscopy as a modern analytical tool for the nondestructive and rapid multi-component analysis of food quality indicators.
关键词: Food products,sugar,predictive models,labeling,pattern analysis,Raman scattering
更新于2025-09-23 15:19:57
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[IEEE 2019 IEEE Research and Applications of Photonics in Defense Conference (RAPID) - Miramar Beach, FL, USA (2019.8.19-2019.8.21)] 2019 IEEE Research and Applications of Photonics in Defense Conference (RAPID) - InGaAs/InAsSb Strained Layer Superlattice Infrared Detectors
摘要: Recent telecommunication systems exploit the degrees of freedom of the radio propagation channel more and more. Deeper investigations of system performance require realistic channel models. For this purpose, a new MIMO UWB channel sounder is introduced. The novelty is its capacity to estimate simultaneously direction of arrival and departure in 3D, including polarization state information. The second novelty is a modified SIC algorithm which speeds up the search of the multipath properties of the propagation channel. An extensive measurement campaign is performed in different residential environments and statistical results are provided.
关键词: ultra wideband technology,Channel models,direction of arrival estimation,radio propagation
更新于2025-09-23 15:19:57