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The performance of the traffic system can drastically drop when nonrecurrent congestion caused by incidents occurs. Early detection and clearing of traffic incidents will enable the mitigation of the congestion and early restoration of normal traffic conditions. The research in this paper utilized the vehicle information from the recent technological advancement in transportation systems, connected vehicles (CV), and loop-detector information for nonconnected vehicles (NCVs) and developed a novel algorithm to (1) control traffic signals for normal traffic conditions in the absence of incidents, (2) detect traffic incidents using CV/NCV information, and (3) control traffic signals during the occurrence and dissipation of incidents. All the 3 strategies were integrated into one algorithm, which runs as per the real-time traffic conditions, in the presence or absence of incidents. Space-mean speeds of the vehicles on nonincident lanes and throughput maximization criteria were taken as the indicators for the activation of specific signal timings directed at the incident-affected approach. Diverse incident scenarios were tested on a four-legged isolated intersection using the VISSIM simulation tool. Incident detection results showed a higher detection rate and lower mean detection time at higher CV penetration and higher traffic volumes, and at the incident locations nearer to the stop-line. The proposed incident-responsive signal control strategy at 40% and higher CV penetration showed better performance over EPICS adaptive signal control solution, in reducing average travel time delay and the average number of stops per vehicle., Author(s): Kancharla K. K. Chandan (corresponding author) [1]; Álvaro J. M. Seco [2]; Ana M. C. Bastos Silva [2] 1. Introduction and Background Nonrecurrent congestion caused by traffic incidents remains [...]

Queue length is a crucial measurement of traffic signal control at urban intersections. Conventional queue length estimation methods mostly still rely on fixed detectors. The development of connected vehicles (CV) provides massive amounts of vehicle trajectory data, and the queue length estimation based on CV data has received considerable attention in recent years. However, most existing CV-based methods require the prior knowledge of the penetration rate of CV and vehicle arrivals, but the estimation of these prior distributions has not been well studied. To address this issue, this paper proposes a cycle-based queue length estimation method under partially connected vehicle (CV) environment, with the prior vehicle arrivals being unknown. The empirical Bayes method is adopted to estimate the arrival rate by leveraging the observed queued CV information such as the number and positions. The hyperparameter estimation problem of the prior distribution is solved by the maximum likelihood estimation (MLE) method. To validate the proposed queue length estimation method, a simulation environment with partially connected vehicles is established using VISSIM and Python for data generating. The results in terms of normalized mean absolute errors (NMAE) and normalized root mean square errors (NRMSE) show that the proposed method could produce accurate and reliable estimated queue length under various CV penetration rates., Author(s): Lu Wei (corresponding author) [1]; Jin-hong Li [1]; Li-wen Xu [2]; Lei Gao [1]; Jian Yang [1] 1. Introduction Queue length is one of the most important performance measures [...]

In this brief paper, we show the neutrino velocity discrepancy obtained in the OPERA experiment may be due to the local Doppler effect between a local clock attached to a given detector at Gran Sasso, say CG, and the respective instantaneous clock crossing CG, say CC, being this latter at rest in the instantaneous inertial frame having got the velocity of rotation of CERN about Earth's axis in relation to the fixed stars. With this effect, the index of refraction of the Earth crust may accomplish a refractive effect by which the neutrino velocity through the Earth crust turns out to be small in relation to the speed of light in the empty space, leading to an encrusted discrepancy that may have contamined the data obtained from the block of detectors at Gran Sasso, leading to a time interval excess e that did not provide an exact match between the shift of the protons PDF (probability distribution function) by [TOF.sub.c] and the detection data at Gran Sasso via the maximum likelihood matching., 1 Definitions and Solution Firstly, the effect investigated here is not the same one that was investigated in [2], but, throughout this paper, we will use some useful configurations defined [...]

Duped: Truth-Default Theory and the Social Science of Lying and Deception By Timothy R. Levine. Tuscaloosa, AL: University of Alabama Press, 2019. 364 pp. Paper, $34.95. One can go back [...]

This paper reports recent advances in the development of a tactile fingerprint sensor made by a CMOS compatible front side bulk micromachining technology. This device enables the measurement of a fingerprint by the way of a mechanical scanning principle of the finger roughness. While this sensing principle has shown good results on a first prototype of reduced width, we present here the design, fabrication and test of a new sensor. This sensor contains 256 pressure sensitive microbeams for a total length of 1.28 cm and is fully integrated with analog and mixed signal electronics. In this paper we will detail the general working principle of the tactile fingerprint sensor and the two prototypes that have been manufactured and tested with a special focus on the electronic architecture and the test results of the second prototype. Index Terms--CMOS compatible bulk micromachining technologies, fingerprint sensor, integrated MEMS, switch capacitor systems.

This review paper presents the current state of the art imaging systems using room-temperature CdTe and CdZnTe X-ray and gamma-ray detectors. Imaging systems composed of both single elements and monolithic segmented CdTe and CdZnTe arrays are used in medical diagnostics, astronomy, research and industry. This paper is divided into two sections: The first section describes different types and configurations of CdTe or CdZnTe detectors used in imaging systems, with the emphasis on single charge carrier collection detectors and front-end read-out electronics in the form of application specific integrated circuits associated with these detectors. It also discusses the advantages, disadvantages and limitations with respect to the efficiency and area of the imaging systems using CdTe and CdZnTe detectors compared to other types of X and gamma ray detectors. The second section describes several examples of imaging systems utilizing CdZnTe detectors: 1) a large area imaging telescope for the detection of gamma ray bursts using a coded aperture collimator; 2) a large area medical nuclear camera for cardiology and scintimammography using a parallel hole collimator; 3) a large field of view gamma camera based on a rotating slat collimator; and 4) a prototype of an electronically collimated Compton camera.

In this paper, we have evaluated the timing properties offered by silicon drift detectors to be used as scintillation photodetectors in systems for medical imaging. The peculiar drift mechanism of the charge created inside the SDD volume is responsible for a rise time of the signal at the output of the device when this is irradiated over its whole active area. Despite this effect, the rise time is in the order of 200 ns for a 5 [mm.sup.2] device, therefore, still comparable with the shaping time used for timing measurements. In this paper, the effect on the timing performances of SDDs due to the drift mechanism is first theoretically evaluated. We have then carried out the experimental characterization of the timing properties of a 5-[mm.sup.2] SDD coupled to a GSO crystal, in coincidence with a NaI-PMT detector, using a [sup.22] Na source. Despite the low conversion gain of the system (2.5 e-/keV), due to the low light output of the crystal and the nonoptimized quantum efficiency of the SDD, a timing resolution of 22 ns was measured for 511 keV photons. This corresponds to a product resolution times number of collected electrons of about 13.9 x [10.sup.3] ns x e-h which is comparable to the one achieved with APDs of similar areas. By irradiating the SDD directly with laser pulses, a resolution better than 1 ns was achieved with more than 60.000 electrons, showing no relevant limitations due to possible jitters of the drift time. Index Terms--Photo-detectors, scintillation, silicon drift detectors, timing measurements.

Traffic signal optimization is a significant means for smoothing urban traffic flow. However, the operation of traffic signals is currently seriously constrained by the data available from traditional point detectors. In recent years, an emerging technology, connected vehicle (CV), which can percept the overall traffic environment in real time, has drawn researchers' attention. With the new data source, traffic controllers should be able to make smarter decisions. A lot of work has been done to develop a new traffic signal control pattern under connected-vehicle environment. This paper provides a comprehensive review of these studies, aiming at sketching out the state of the arts in this research field. Several basic control problems, communication, control input, and objectives, are briefly introduced. The commonly used optimization models for this problem are summarized into three types: rule-based models, mathematical programming-based models, and artificial intelligence-based models. Then some major technical issues are discussed in detail. Finally, we raise the limitation of the existing studies and give our perspectives of the future research directions., Author(s): Jindong Wang [1,2]; Shengchuan Jiang (corresponding author) [1]; Yue Qiu [1]; Yang Zhang [3]; Jianguo Ying [2]; Yuchuan Du [1] 1. Introduction The recent years have witnessed an exponential [...]