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oe1(光电查) - 科学论文

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  • [IEEE 2018 IEEE CPMT Symposium Japan (ICSJ) - Kyoto, Japan (2018.11.19-2018.11.21)] 2018 IEEE CPMT Symposium Japan (ICSJ) - A 77GHz Antenna-in-Package with Low-Cost Solution for mm Wave System Integration

    摘要: This work provides Antenna in package (AiP) implemented on Advanced single sided substrates (aS3 package) , which utilizes low-cost substrate and low-cost assembly process. The dipole antenna implemented on aS3 package results in a peak gain of 5 dBi at operating frequency band. The return loss of < - 10 dB bandwidth is from 65 to 81 GHz. The resonant rectangular series-fed patch array implemented on aS3 package results in a peak gain of 8 dBi at operating frequency band. The return loss of < - 10 dB bandwidth is from 76 to 81 GHz. The antenna performance of antenna on aS3 package meets the requirements of 77 GHz automotive radar systems. This work also discuss with the impact of fabrication inaccuracies on the antenna bandwidth and gain. For 77 GHz automotive radar application, the corner analysis of process variation supports correct antenna performance and a short time to market.

    关键词: Advanced single sided substrates (aS3 package),fabrication inaccuracies,resonant rectangular series-fed patch array,dipole antenna,Antenna in package (AiP),77 GHz automotive radar systems

    更新于2025-09-23 15:22:29

  • [IEEE 2018 IEEE 12th International Symposium on Embedded Multicore/Many-core Systems-on-Chip (MCSoC) - Hanoi (2018.9.12-2018.9.14)] 2018 IEEE 12th International Symposium on Embedded Multicore/Many-core Systems-on-Chip (MCSoC) - Designing Compact Convolutional Neural Network for Embedded Stereo Vision Systems

    摘要: Autonomous systems are used in a wide range of domains from indoor utensils to autonomous robot surgeries and self-driving cars. Stereo vision cameras probably are the most flexible sensing way in these systems since they can extract depth, luminance, color, and shape information. However, stereo vision based applications suffer from huge image sizes and computational complexity leading system to higher power consumption. To tackle these challenges, in the first step, GIMME2 stereo vision system [1] is employed. GIMME2 is a high-throughput and cost efficient FPGA-based stereo vision embedded system. In the next step, we present a framework for designing an optimized Deep Convolutional Neural Network (DCNN) for time constraint applications and/or limited resource budget platforms. Our framework tries to automatically generate a highly robust DCNN architecture for image data receiving from stereo vision cameras. Our proposed framework takes advantage of a multi-objective evolutionary optimization approach to design a near-optimal network architecture for both the accuracy and network size objectives. Unlike recent works aiming to generate a highly accurate network, we also considered the network size parameters to build a highly compact architecture. After designing a robust network, our proposed framework maps generated network on a multi/many core heterogeneous System-on-Chip (SoC). In addition, we have integrated our framework to the GIMME2 processing pipeline such that it can also estimate the distance of detected objects. The generated network by our framework offers up to 24x compression rate while losing only 5% accuracy compare to the best result on the CIFAR-10 dataset.

    关键词: Deep Convolutional Neural Network,Stereo Vision Systems,Neural Processing Unit,Neural Network Architecture Search

    更新于2025-09-23 15:22:29

  • [IEEE IGARSS 2018 - 2018 IEEE International Geoscience and Remote Sensing Symposium - Valencia (2018.7.22-2018.7.27)] IGARSS 2018 - 2018 IEEE International Geoscience and Remote Sensing Symposium - A Doppler Centroid Estimator for Synthetic Aperture Radar Based on Phase Center Point Tracking

    摘要: Heterogeneity is an important feature of multiagent systems. This paper addresses the consensus problem of heterogeneous multiagent systems composed of first-integrator and double-integrator agents. The dynamics of each agent switches between continuous-time and discrete-time dynamics. By using the graph theory and nonnegative matrix theory, we derive that the system can achieve consensus if and only if the fixed interaction topology has a directed spanning tree. For switching topologies, we get that the system can reach consensus if each interaction topology has a directed spanning tree. Simulation examples are provided to demonstrate the effectiveness of our theoretical results.

    关键词: switching dynamics,nonnegative matrix theory,consensus,heterogeneous multiagent systems,graph theory

    更新于2025-09-23 15:22:29

  • PWM as a Low Cost Method for the Analog Control of MEMS Devices

    摘要: In this paper, we discuss the use of pulse width modulation (PWM) to control analog MEMS devices. We achieve a precise linear analog control of MEMS by applying PWM signal with a frequency well above the system’s mechanical natural frequency. We first demonstrate this using a parallel plate actuator and comb-drive, and then extend the technique to control a commercial deformable mirror. Such an approach allows the system designer to replace expensive drive electronics such as the high precision DACs and high voltage, linear amplifiers with a simple on-off switch. The advancements in the electronics industry tend to make precise timing cheaper and faster; our approach exploits these long-term trends to create low-cost control circuits. We also show how PWM control can linearize the positional response of the devices, where typically the position would depend quadratically on the applied analog voltage.

    关键词: linearize,pulse width modulation,Microelectromechanical systems,electrostatic actuator

    更新于2025-09-23 15:22:29

  • [IEEE 2018 25th International Conference on Mechatronics and Machine Vision in Practice (M2VIP) - Stuttgart, Germany (2018.11.20-2018.11.22)] 2018 25th International Conference on Mechatronics and Machine Vision in Practice (M2VIP) - Range-Based Collaborative MSCKF Localization

    摘要: In this paper, a framework for collaborative localization of heterogenous systems is presented. Making advantage of the original MSCKF framework, we design a collaborative MSCKF filter that operates in two levels and allows a decentralized 3D collaborative localization without use of external computation systems. To achieve that, based on MSCKF localization, we first propose a range based collaboration that we optimize using the extracted environment constraints, an operation allowed by the use of a truncated unscented kalman filtering updates. The collaborative filtering is managed to not impact the original MSCKF odometry properties. The framework is applied to collaborative localization of aerial and ground robots; experimental results show the effectiveness of the proposed method.

    关键词: Collaborative localization,Multi-robot systems,MSCKF

    更新于2025-09-23 15:22:29

  • [IEEE 2018 Eleventh International Conference "Management of large-scale system development" (MLSD 2018) - Moscow (2018.10.1-2018.10.3)] 2018 Eleventh International Conference "Management of large-scale system development" (MLSD - Portable Devices for Monitoring Ultraviolet Radiation

    摘要: The article deals with issues related to the use of the new elemental base in some control and monitoring systems for the principles of large-scale objects, constructing portable devices for monitoring ultraviolet radiation. These are the semiconductor sensors - a doser that gives a quantitative result on a digital indicator, either delivering a light or sound signal when reaching a predetermined radiation dose and a dosimeter that measures the intensity of UV radiation or the dose received in real physical units of measurement.

    关键词: UV radiation,control systems,sensor,large-scale objects,semiconductor,monitoring,portable device

    更新于2025-09-23 15:22:29

  • Cooperative Operation of R-SFCL and Online Current Limitation Strategy of GCPVS under Asymmetrical Faults

    摘要: Grid-connected photovoltaic (GCPVS) should remain grid-connected and inject specified reactive current in accordance with fault-ride-through (FRT) requirements. To minimize voltage ripples on the DC link voltage and restrict the maximum phase currents, a modified online current limitation strategy (OCLS) is presented in this paper. Transient performance of GCPVS is enhanced as resistive-type superconducting fault current limiter (R-SFCL) is applied under severe asymmetrical faults. By introducing proper resistance selection process, the cooperative operation of OCLS and SFCL is proved to be effective.

    关键词: reactive power control,transient performance,superconducting fault current limiters (FCL),online current limitation strategy (OCLS),photovoltaic systems,Fault ride-through (FRT) capability,symmetrical and asymmetrical faults

    更新于2025-09-23 15:22:29

  • [IEEE 2018 53rd International Universities Power Engineering Conference (UPEC) - Glasgow, United Kingdom (2018.9.4-2018.9.7)] 2018 53rd International Universities Power Engineering Conference (UPEC) - Optimal Siting of BESS in Distribution Networks under High PV Penetration

    摘要: This paper focuses on the optimal siting of Battery Energy Storage Systems (BESS) in a Distribution Network with installed Photovoltaic Generation, in order to minimize the energy losses of the system. The bus voltage limit, as well as the ampacity level of the lines are taken into consideration as constraints, while the technical constraints of the BESSs have also been taken into account. Unified Particle Swarm Optimization is used as the solving optimization technique. Simulations are being carried out on IEEE-33 bus system regarding different scenarios and the results are presented and compared. A significant improvement in energy losses, voltage and line ampacity profile is achieved by the introduction of BESS units in a Distribution Network with high PV Penetration.

    关键词: BESS,Particle Swarm Optimization,Distributed Generation,Battery Energy Storage Systems,PV,optimal sizing siting of ESS,PSO

    更新于2025-09-23 15:22:29

  • Radial velocity follow-up of GJ1132 with HARPS

    摘要: The source GJ1132 is a nearby red dwarf known to host a transiting Earth-size planet. After its initial detection, we pursued an intense follow-up with the HARPS velocimeter. We now confirm the detection of GJ1132b with radial velocities alone. We refined its orbital parameters, and in particular, its mass (mb = 1.66 ± 0.23 M⊕), density (ρb = 6.3 ± 1.3 g cm?3), and eccentricity (eb < 0.22; 95%). We also detected at least one more planet in the system. GJ1132c is a super-Earth with period Pc = 8.93 ± 0.01 days and minimum mass mc sin ic = 2.64 ± 0.44 M⊕. Receiving about 1.9 times more flux than Earth in our solar system, its equilibrium temperature is that of a temperate planet (Teq = 230?300 K for albedos A = 0.75 ? 0.00), which places GJ1132c near the inner edge of the so-called habitable zone. Despite an a priori favorable orientation for the system, Spitzer observations reject most transit configurations, leaving a posterior probability <1% that GJ1132c transits. GJ1132(d) is a third signal with period Pd = 177 ± 5 days attributed to either a planet candidate with minimum mass md sin id = 8.4+1.7?2.5 M⊕ or stellar activity. Its Doppler signal is the most powerful in our HARPS time series but appears on a timescale where either the stellar rotation or a magnetic cycle are viable alternatives to the planet hypothesis. On the one hand, the period is different than that measured for the stellar rotation (~125 days), and a Bayesian statistical analysis we performed with a Markov chain Monte Carlo and Gaussian processes demonstrates that the signal is better described by a Keplerian function than by correlated noise. On the other hand, periodograms of spectral indices sensitive to stellar activity show power excess at similar periods to that of this third signal, and radial velocity shifts induced by stellar activity can also match a Keplerian function. We, therefore, prefer to leave the status of GJ1132(d) undecided.

    关键词: techniques: radial velocities,planetary systems,stars: late-type

    更新于2025-09-23 15:22:29

  • SOPHIE velocimetry of <i>Kepler</i> transit candidates

    摘要: Kepler-419 is a planetary system discovered by the Kepler photometry which is known to harbour two massive giant planets: an inner 3 MJ transiting planet with a 69.8-day period, highly eccentric orbit, and an outer 7.5 MJ non-transiting planet predicted from the transit-timing variations (TTVs) of the inner planet b to have a 675-day period, moderately eccentric orbit. Here we present new radial velocity (RV) measurements secured over more than two years with the SOPHIE spectrograph, where both planets are clearly detected. The RV data is modelled together with the Kepler photometry using a photodynamical model. The inclusion of velocity information breaks the MR?3 degeneracy inherent in timing data alone, allowing us to measure the absolute stellar and planetary radii and masses. With uncertainties of 12 and 13% for the stellar and inner planet radii, and 35, 24, and 35% for the masses of the star, planet b, and planet c, respectively, these measurements are the most precise to date for a single host star system using this technique. The transiting planet mass is determined at better precision than the star mass. This shows that modelling the radial velocities and the light curve together in systems of dynamically interacting planets provides a way of characterising both the star and the planets without being limited by knowledge of the star. On the other hand, the period ratio and eccentricities place the Kepler-419 system in a sweet spot; had around twice as many transits been observed, the mass of the transiting planet could have been measured using its own TTVs. Finally, the origin of the Kepler-419 system is discussed. We show that the system is near a coplanar high-eccentricity secular fixed point, related to the alignment of the orbits, which has prevented the inner orbit from circularising. For most other relative apsidal orientations, planet b’s orbit would be circular with a semi-major axis of 0.03 au. This suggests a mechanism for forming hot Jupiters in multiplanetary systems without the need of high mutual inclinations.

    关键词: planetary systems,techniques: photometric,techniques: radial velocities

    更新于2025-09-23 15:22:29