PotholeEye^(+): Deep-Learning Based Pavement Distress Detection System toward Smart Maintenance

We propose a mobile system,called PotholeEye+,for automatically monitoring the surface of a roadway and detecting the pavement distress in real-time through analysis of a video.PotholeEye+pre-processes the images,extracts features,and classifies the distress into a variety of types,while the road manager is driving.Every day for a year,we have tested PotholeEye+on real highway involving real settings,a camera,a mini computer,a GPS receiver,and so on.Consequently,PotholeEye+detected the pavement distress with accuracy of 92%,precision of 87%and recall 74%averagely during driving at an average speed of 110 km/h on a real highway.

Interference Cancellation Algorithm for 2×2 MIMO System without Pilot in LTE

Interference cancellation system (ICS) for 3GPP/LTE system is the broadband cancellation system, which receives forward signal through the donor antenna. We proposed new algorithm of received signal with pilot and non-pilot design. Although repeater design needs our project, so in this paper we discuss about interference cancellation algorithm for 2x2 MIMO systems without pilot in LTE. First explain the general principle structure of 3GPP/LTE, next determine our new design and algorithm. Finally, we simulated our mathematic extraction of proposed new algorithm on MATLAB.

Lanthanide-Activated Fiber Materials for Broadband Optical Amplifiers

Some intra-4/-configurational transitions of lanthanide, of which radiative emissions cover in wavelengths the optical communication window of the currently available OH-free silica-based line fibers, are discussed in terms of relationship between their emission properties and host fiber materials.

A novel method for PAPR reduction of the OFDM signal using nonlinear scaling and FM

Orthogonal frequency division multiplexing (OFDM) has been adopted as standard beginning with the 4th generation mobile communication system because of its high-bit-rate transmission capability under frequency selective fading channel con-ditions. However, a major disadvantage of OFDM is the non-constant envelope signal with a high peak-to-average power ratio (PAPR). The high peak signal in OFDM is distorted through a nonlinear amplifier, which causes bit error ratio (BER) reduction. Many techniques have been developed for reducing PAPR at the cost of inefficient bandwidth usage or throughput because of the additional information about PAPR reduction. We propose a novel method, in which the high peak signal above the threshold of the nonlinear amplification region is nonlinearly downscaled to lower the PAPR. The time slot location and scaling ratio for where and how the high peak baseband OFDM signal is downscaled are transmitted using frequency modulation (FM) combined with OFDM, which requires less additional bandwidth than the previously proposed methods. Simulation results show that the pro-posed novel method provides a lower PAPR and elicits a better BER performance compared with other conventional methods, because it reduces the PAPR by nonlinear scaling and restores the pre-distorted signal using FM.

On-skin and tele-haptic application of mechanically decoupled taxel array on dynamically moving and soft surfaces

To accurately probe the tactile information on soft skin,it is critical for the pressure sensing array to be free of noise and inter-taxel crosstalk,irrespective of the measurement condition.However,on dynamically moving and soft surfaces,which are common conditions for on-skin and robotic applications,obtaining precise measurement without compromising the sensing performance is a significant challenge due to mechanical coupling between the sensors and with the moving surface.In this work,multi-level architectural design of micro-pyramids and trapezoid-shaped mechanical barrier array was implemented to enable accurate spatiotemporal tactile sensing on soft surfaces under dynamic deformations.Trade-off relationship between limit of detection and bending insensitivity was discovered,which was overcome by employing micropores in barrier structures.Finally,in-situ pressure mapping on dynamically moving soft surfaces without signal distortion is demonstrated while human skin and/or soft robots are performing complicated tasks such as reading Braille and handling the artificial organs.

A Ray Tracing and Joint Spectrum Based Clustering and Tracking Algorithm for Internet of Intelligent Vehicles

Driven by the rapid growth in information services provided by the Internet and the appearance of new multimedia applications,millimeter wave is foreseen as a key enabler towards the Internet of intelligent vehicles(IoIV)for urban traffic safety enhancement.In this regard,cluster-based channel modeling has become an important research topic in the realm of emergency communications.To fully understand the cluster-based channel model,a series of vehicle-to-infrastructure(V2I)channel simulations at 22.6 GHz are conducted by a three-dimensional ray tracing(RT)simulator.The clustering and tracking algorithm is proposed and analyzed from three aspects by the obtained simulation results.The multiple signal classification estimation spectrum is applied to restrain the influence of antenna sidelobes and identify targets at first.Based on the fundamentals,the clusters can be identified and subsequently tracked using the proposed approach.The impacts of antenna sidelobes,angle resolution of beam rotation,and non-line-of-sight propagation path on the performance of clustering and tracking are evaluated.The multi-component-level RT results are adopted as comparison benchmarks,which reflect the ground truth.This work aims to provide a full picture of the clustering characteristics for designing and analyzing emergency communication systems.

Shape-tailored whispering gallery microcavity lasers designed by transformation optics

Semiconductor microdisk lasers have great potential as low-threshold,high-speed,and small-form-factor light sources required for photonic integrated circuits because of their high-Q factors associated with long-lived whispering gallery modes(WGMs).Despite these advantages,the rotational symmetry of the disk shape restricts practical applications of the photonic devices because of their isotropic emission,which lacks directionality in far-field emission and difficulty in free-space out coupling.To overcome this problem,deformation of the disk cavity has been mainly attempted.However,the approach cannot avoid significant Q degradation owing to the broken rotational symmetry.Here,we first report a deformed shape microcavity laser based on transformation optics,which exploits WGMs free from Q degradation.The deformed cavity laser was realized by a spatially varying distribution of deep-sub-wavelength-scale(60 nm diameter)nanoholes in an InGaAsP-based multi-quantum-well heterostructure.The lasing threshold of our laser is one-third of that of the same shaped homogeneous laser and quite similar to that of a homogeneous microdisk laser.The results mean that Q spoiling caused by the boundary shape deformation is recovered by spatially varying nanohole density distribution designed by transformation optics and effective medium approximation.

Do different kinds of photon-pair sources have the same indistinguishability in quantum silicon photonics?

In the same silicon photonic integrated circuit,we compare two types of integrated degenerate photon-pair sources(microring resonators and waveguides)using Hong–Ou–Mandel(HOM)interference experiments.Two nominally identical microring resonators are coupled to two nominally identical waveguides,which form the arms of a Mach–Zehnder interferometer.This is pumped by two lasers at two different wavelengths to generate,by spontaneous four-wave mixing,degenerate photon pairs.In particular,the microring resonators can be thermally tuned in or out of resonance with the pump wavelengths,thus choosing either the microring resonators or the waveguides as photon-pair sources,respectively.In this way,an on-chip HOM visibility of 94%with microring resonators and 99%with straight waveguides is measured upon filtering.We compare our experimental results with theoretical simulations of the joint spectral intensity and the purity of the degenerate photon pairs.We verify that the visibility is connected to the sources’indistinguishability,which can be quantified by the overlap between the joint spectral amplitudes(JSA)of the photon pairs generated by the two sources.We estimate a JSA overlap of 98%with waveguides and 89%with microring resonators.

Electrically driven, phosphor-free, white light-emitting diodes using gallium nitride-based double concentric truncated pyramid structures

White light-emitting diodes(LEDs)are becoming an alternative general light source,with huge energy savings compared to conventional lighting.However,white LEDs using phosphor(s)suffer from unavoidable Stokes energy converting losses,higher manufacturing cost,and reduced thermal stability.Here,we demonstrate electrically driven,phosphor-free,white LEDs based on three-dimensional gallium nitride structures with double concentric truncated hexagonal pyramids.The electroluminescence spectra are stable with varying current.The origin of the emission wavelength is studied by cathodoluminescence and high-angle annular dark field scanning transmission electron microscopy experiments.Spatial variation of the carrier injection efficiency is also investigated by a comparative analysis between spatially resolved photoluminescence and electroluminescence.

DICE:An Effective Query Result Cache for Distributed Storage Systems

Due to the proliferation of Internet and Intranet,the distributed storage systems have received a lot of attention. These systems span a large number of machines and store huge amount of data for a lot of users.In the distributed storage systems,a row can be directly accessed using a row key.We concentrate on a problem of efficient processing of queries whose predicate is on a column but not a row key.In this paper,we present a cache management technique,called DICE which maintains query results of range queries to support the next range queries.To accelerate the search time of the cached query results,we use modified Interval Ski Lists.In addition,we devise a novel cache replacement policy since DICE maintains an interval rather than a data item.Since our cache replacement policy considers the properties of intervals,our proposed technique is more efficient than traditional buffer replacement algorithms.Our experimental result demonstrates the efficiency of our proposed technique.

Computational discovery of p-type transparent oxide semiconductors using hydrogen descriptor

The ultimate transparent electronic devices require complementary and symmetrical pairs of n-type and p-type transparent semiconductors.While several n-type transparent oxide semiconductors like InGaZnO and ZnO are available and being used in consumer electronics,there are practically no p-type oxides that are comparable to the n-type counterpart in spite of tremendous efforts to discover them.Recently,high-throughput screening with the density functional theory calculations attempted to identify candidate p-type transparent oxides,but none of suggested materials was verified experimentally,implying need for a better theoretical predictor.Here,we propose a highly reliable and computationally efficient descriptor for p-type dopability—the hydrogen impurity energy.We show that the hydrogen descriptor can distinguish well-known p-type and n-type oxides.Using the hydrogen descriptor,we screen most binary oxides and a selected pool of ternary compounds that covers Sn^(2+)-bearing and Cu^(1+)-bearing oxides as well as oxychalcogenides.As a result,we suggest La_(2)O_(2)Te and CuLiO as promising p-type oxides.

Analytic design of information granulation-based fuzzy radial basis function neural networks with the aid of multiobjective particle swarm optimization

Purpose–The purpose of this paper is to consider the concept of Fuzzy Radial Basis Function Neural Networks with Information Granulation(IG-FRBFNN)and their optimization realized by means of the Multiobjective Particle Swarm Optimization(MOPSO).Design/methodology/approach–In fuzzy modeling,complexity,interpretability(or simplicity)as well as accuracy of the obtained model are essential design criteria.Since the performance of the IG-RBFNN model is directly affected by some parameters,such as the fuzzification coefficient used in the FCM,the number of rules and the orders of the polynomials in the consequent parts of the rules,the authors carry out both structural as well as parametric optimization of the network.A multi-objective Particle Swarm Optimization using Crowding Distance(MOPSO-CD)as well as O/WLS learning-based optimization are exploited to carry out the structural and parametric optimization of the model,respectively,while the optimization is of multiobjective character as it is aimed at the simultaneous minimization of complexity and maximization of accuracy.Findings–The performance of the proposed model is illustrated with the aid of three examples.The proposed optimization method leads to an accurate and highly interpretable fuzzy model.Originality/value–A MOPSO-CD as well as O/WLS learning-based optimization are exploited,respectively,to carry out the structural and parametric optimization of the model.As a result,the proposed methodology is interesting for designing an accurate and highly interpretable fuzzy model.

Additional Sensitivity Penalty of Burst Mode Receivers in Ethernet PON due to Extinction Ratio

An additional sensitivity penalty of burst mode receivers due to the extinction ratio is analyzed considering the specific transmitter control in Ethernet PON. For an extinction ratio of 6dB, a penalty of 8dB occurs additionally.

550 MHz carbon nanotube mode-locked femtosecond Cr:YAG laser

We demonstrate a femtosecond Cr：YAG laser mode-locked by a carbon nanotube saturable absorber mirror（CNT-SAM） at a repetition rate of 550 MHz. By employing the CNT-SAM, which exhibits a modulation depth of 0.51% and a saturation fluence of 28 μJ∕cm^2 at 1.5 μm, we achieved a compact bulk Cr：YAG laser with selfstarting mode-locked operation near 1.5 μm, delivering an average output power of up to 147 m W and a pulse duration of 110 fs. To our knowledge, this system provides the highest repetition rate among reported CNT-SAM mode-locked Cr：YAG lasers and the shortest pulse duration among saturable absorber mode-locked Cr：YAG lasers with repetition rates above 500 MHz.

Highly pixelated,untethered tactile interfaces for an ultra-flexible on-skin telehaptic system

Realizing highly immersive tactile interactions requires a skin-integrated,untethered,high-definition tactile transducer devices that can record and generate tactile stimuli.However,the rigid and bulky form factor,and insufficient resolution of existing actuators are hindering the reproduction of sophisticated tactile sensations and immersive user experiences.Here,we demonstrate an ultraflexible tactile interface with high spatial resolution of 1.8 mm for telehaptic communication on human skin.Dual mechanism sensors and sub-mm scale piezoceramic actuators are designed to record and generate the static and dynamic pressures in a wide frequency range(1 Hz to 1 kHz).Moreover,actuators are integrated on ultra-flexible substrate with chessboard pattern to minimize stress during mechanical deformations.Finally,remote transmissions of various tactile stimuli,such as shapes,textures,and vibration patterns were demonstrated by the telehaptic system with low latency(<1.55 ms)and high fidelity as proven by the shorttime Fourier-transform analysis.