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- 摘要
- 关键词
- 实验方案
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[IEEE NAECON 2018 - IEEE National Aerospace and Electronics Conference - Dayton, OH, USA (2018.7.23-2018.7.26)] NAECON 2018 - IEEE National Aerospace and Electronics Conference - Onboard Image Processing for Small Satellites
摘要： In general, the computational ability of spacecraft and satellites has lagged behind terrestrial computers by several generations. Moore's Law turns the supercomputers of yesterday into the laptops of today, but space computing remains relatively underpowered due to the harsh radiation environment and low risk-tolerance of most space missions. Space missions are generally low risk because of the high cost of components and launch. However, launch costs are drastically decreasing and innovations such as CubeSats are changing the risk equation. By accepting more risk and utilizing commercial of the shelf (COTS) parts, it is possible to cheaply build and launch extremely capable computing platforms into space. High performance satellites will be required for advanced interplanetary exploration due to latency challenges. The long transmission times between planets means satellites or robotic explorers need onboard processing to perform tasks in real-time. This paper explores one possible application that could be hosted onboard the next generation of high performance satellites, performing object classification on satellite imagery. Automation of satellite imagery processing is currently performed by servers or workstations on Earth, but this paper will show that those algorithms can be moved onboard satellites by using COTS components. First traditional computer vision techniques such as edge detection and sliding windows are used to detect possible objects on the open ocean. Then a modern neural network architecture is used to classify the object as a ship or not. This application is implemented on a Nvidia Jetson TX2 and measurements of the application's power use confirm that it fits within the Size Weight and Power (SWAP) requirements of SmallSats and possibly even CubeSats.
关键词： Satellite Imagery,Machine Learning,Neural Networks,Onboard Processing
更新于2025-09-23 15:22:29
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Memory-assisted quantum key distribution resilient against multiple-excitation effects
摘要： Memory-assisted measurement-device-independent quantum key distribution (MA-MDI-QKD) has recently been proposed as a technique to improve the rate-versus-distance behavior of QKD systems by using existing, or nearly-achievable, quantum technologies. The promise is that MA-MDI-QKD would require less demanding quantum memories than the ones needed for probabilistic quantum repeaters. Nevertheless, early investigations suggest that, in order to beat the conventional memory-less QKD schemes, the quantum memories used in the MA-MDI-QKD protocols must have high bandwidth-storage products and short interaction times. Among different types of quantum memories, ensemble-based memories offer some of the required specifications, but they typically suffer from multiple excitation effects. To avoid the latter issue, in this paper, we propose two new variants of MA-MDI-QKD both relying on single-photon sources for entangling purposes. One is based on known techniques for entanglement distribution in quantum repeaters. This scheme turns out to offer no advantage even if one uses ideal single-photon sources. By finding the root cause of the problem, we then propose another setup, which can outperform single memory-less setups even if we allow for some imperfections in our single-photon sources. For such a scheme, we compare the key rate for different types of ensemble-based memories and show that certain classes of atomic ensembles can improve the rate-versus-distance behavior.
关键词： quantum cryptography,quantum networks,quantum key distribution (QKD),quantum memory,single-photon source,quantum communications
更新于2025-09-23 15:22:29
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Planning Solar in Energy-Managed Cellular Networks
摘要： Recently, there has been a lot of interest on the energy efficiency and environmental impact of wireless networks. Given that the base stations are the network elements that use most of this energy, much research has dealt with ways to reduce the energy used by the base stations by turning them off during periods of low load. In addition to this, installing a solar harvesting system made up of solar panels, batteries, charge controllers, and inverters is another way to further reduce the network environmental impact, and some research has been dealing with this for individual base stations. In this paper, we show that both techniques are tightly coupled. We propose a mathematical model that captures the synergy between solar installation over a network and the dynamic operation of energy-managed base stations. We study the interactions between the two methods for networks of hundreds of base stations and show that the order in which each method is introduced into the system does make a difference in terms of cost and performance. We also show that installing solar is not always the best solution even when the unit cost of the solar energy is smaller than the grid cost. We conclude that planning the solar installation and energy management of the base stations has to be done jointly.
关键词： Cellular networks,solar power,energy management,sleep mode
更新于2025-09-23 15:22:29
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A review of image-based automatic facial landmark identification techniques
摘要： The accurate identification of landmarks within facial images is an important step in the completion of a number of higher-order computer vision tasks such as facial recognition and facial expression analysis. While being an intuitive and simple task for human vision, it has taken decades of research, an increase in the availability of quality data sets, and a dramatic improvement in computational processing power to achieve near-human accuracy in landmark localisation. The intent of this paper is to provide a review of the current facial landmarking literature, outlining the significant progress that has been made in the field from classical generative methods to more modern techniques such as sophisticated deep neural network architectures. This review considers a generalised facial landmarking problem and provides experimental examples for each stage in the process, reporting repeatable benchmarks across a number of publicly available datasets and linking the results of these examples to the recently reported performance in the literature.
关键词： Vision,Landmarking,Face,Registration,Survey,Image,Review,Artificial neural networks,Deep learning,Machine learning
更新于2025-09-23 15:22:29
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Microwave photonics‐based all optical wavelength conversion of Nyquist‐DP‐16QAM for flex‐grid optical networks with 112 Gbps
摘要： We propose and demonstrate an all optical wavelength conversion of Nyquist differential phase 16 quadrature amplitude modulation based on microwave photonics signal processing for flex-grid optical networks. By analyzing the mechanism of the microwave photonics and the components, multi-adjusting the parameters of wavelength tunable laser with smooth and adjustable optical intensity can be obtained. Then, the multi-channel photonic signals with the minimal guard space of 5 GHz can be obtained, which provide more than 20 flex-grids for optical transmission with transparent rate and format. The optical power of converted wavelengths, optical signal-to-noise ratio, error vector magnitude, and bit error rate (BER) are studied under the condition of different flex-grids, the frequencies of which are from 15 GHz to 36 GHz. The channel frequency spacing and amplitude of the converted wavelength can be dynamically adjusted via parameter configuration. Flex-grid spacing strategies and channel selecting strategies are given. The BER performance of all converted channels can fall below the forward error correction threshold of 3.8 × 10?3 by optimizing the optical power of the receiver end. The results show the tradeoff between the BER and the detected optical power of the receiver end. These research findings could provide solutions for spectrum allocation and routing selection when wavelength conversion is needed in optical links.
关键词： coherent communication,microwave photonics,wavelength conversion,flex-grid optical networks
更新于2025-09-23 15:22:29
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[IEEE 2017 International Conference on Optical Network Design and Modeling (ONDM) - Budapest (2017.5.15-2017.5.18)] 2017 International Conference on Optical Network Design and Modeling (ONDM) - Orchestrating data-intensive vNF service chains in inter-DC elastic optical networks
摘要： We investigate the problem of data-intensive vNF service chain (vNF-SC) orchestration in inter-datacenter EONs. After analyzing the N P-hardness of this problem, we solve it in a sequential manner by optimizing both the request serving sequence and the data-intensive vNF-SC orchestration. Specifically, we propose a request sorting algorithm and a data-intensive vNF-SC orchestration algorithm based on dynamic programming to minimize the service completion time. We conduct simulations to evaluate the proposed algorithms, and simulation results verify their effectiveness.
关键词： Network Function Virtualization,vNF Service Chain,Bulk-Data Transfer,Elastic optical networks
更新于2025-09-23 15:22:29
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[IEEE 2018 26th International Conference on Software, Telecommunications and Computer Networks (SoftCOM) - Split (2018.9.13-2018.9.15)] 2018 26th International Conference on Software, Telecommunications and Computer Networks (SoftCOM) - Car to X Communication with Optical Wireless as Support and Alternative to RF-Technologies for Roads and Future Transportation
摘要： Among the different types of lasers and light sources for Communications, new components are becoming more and more important also for Optical Wireless and Optical Sensing applications. In this contribution, combinations of Optical- and RF-Wave Propagation are illustrated, considering also new technologies of lasers and fibre lasers. The presentation includes Optical Wireless Communication (OWC, well known as Free Space Optics (FSO)) as hybrid transmission methods with telecommunication technologies (like WIFI, RF- and Satellite Communications) and also Sensing Technologies (like LiDAR and radar combinations). Important characteristics of physical layer including useful Modulations, Forward Error Correction Coding for single light source are considered. Furthermore, different cases for enhancing the SNR in daytime condition are discussed. The contribution deals with possible fields of application for optical wireless in conjunction with automated driving.
关键词： Car to X Communication,Optical Wireless Communications,light sources,hybrid networks
更新于2025-09-23 15:22:29
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Forecasting Solar Power Using Long-Short Term Memory and Convolutional Neural Networks
摘要： As solar photovoltaic (PV) generation becomes cost-effective, solar power comes into its own as the alternative energy with the potential to make up a larger share of growing energy needs. Consequently, operations and maintenance cost now have a large impact on the profit of managing power modules, and the energy market participants need to estimate the solar power in short or long terms of future. In this paper, we propose a solar power forecasting technique by utilizing convolutional neural networks and long–short-term memory networks recently developed for analyzing time series data in the deep learning communities. Considering that weather information may not be always available for the location where PV modules are installed and sensors are often damaged, we empirically confirm that the proposed method predicts the solar power well with roughly estimated weather data obtained from national weather centers as well as it works robustly without sophisticatedly preprocessed input to remove outliers.
关键词： convolutional neural networks,deep learning,long-short term memory,Solar power forecasting
更新于2025-09-23 15:22:29
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[IEEE 2018 IEEE 23rd International Workshop on Computer Aided Modeling and Design of Communication Links and Networks (CAMAD) - Barcelona (2018.9.17-2018.9.19)] 2018 IEEE 23rd International Workshop on Computer Aided Modeling and Design of Communication Links and Networks (CAMAD) - Harvesting artificial light indoors to power perpetually a Wireless Sensor Network node
摘要： Wireless Sensor Networks (WSN) devices are usually battery powered and thereby their lifetime is limited. This issue leads to lose data measurements and thus to a performance loss of the underlying WSN application. It also increases the maintenance cost in Internet of Things (IoT) scenarios with a huge number of WSN devices. Energy harvesting (EH) is one of the key technologies to solve this issue. In this paper, energy harvesting by artificial light is proposed to power WSN devices in indoor scenarios. Contrary to the state-of-the-art related work, this paper experimentally demonstrates that it is possible, under certain conditions, to achieve energy neutral WSN devices by harvesting energy from artificial light. The experimental setup consists of an EH module, which powers a WSN source data acquisition node, and a WSN sink node which receives the data sent by the first. The EH module consists of a photovoltaic (PV) cell, a boost converter and a 3V coin battery.
关键词： photovoltaic cell,Wireless Sensor Networks,Energy harvesting,boost converter,Internet of Things
更新于2025-09-23 15:22:29
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Hand Gesture Recognition in Automotive Human–Machine Interaction Using Depth Cameras
摘要： In this review, we describe current Machine Learning approaches to hand gesture recognition with depth data from time-of-flight sensors. In particular, we summarise the achievements on a line of research at the Computational Neuroscience laboratory at the Ruhr West University of Applied Sciences. Relating our results to the work of others in this field, we confirm that Convolutional Neural Networks and Long Short-Term Memory yield most reliable results. We investigated several sensor data fusion techniques in a deep learning framework and performed user studies to evaluate our system in practice. During our course of research, we gathered and published our data in a novel benchmark dataset (REHAP), containing over a million unique three-dimensional hand posture samples.
关键词： time-of-flight sensors,hand gesture recognition,automotive,human–machine interaction,neural networks
更新于2025-09-23 15:22:29