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Piezoelectric micromachined ultrasonic transducer (pMUT) rangefinders have been rapidly developed in the last decade. With high output pressure to enable long-range detection and low power consumption (16 μW for over 1 m range detection has been reported), pMUT rangefinders have drawn extensive attention to mobile range-finding. pMUT rangefinders with different strategies to enhance range-finding performance have been developed, including the utilization of pMUT arrays, advanced device structures, and novel piezoelectric materials, and the improvements of range-finding methods. This work briefly introduces the working principle of pMUT rangefinders and then provides an extensive overview of recent advancements that improve the performance of pMUT rangefinders, including advanced pMUT devices and range-finding methods used in pMUT rangefinder systems. Finally, several derivative systems of pMUT rangefinders enabling pMUT rangefinders for broader applications are presented. [ABSTRACT FROM AUTHOR]

The enormous advances in sensing and data processing technologies in combination with recent developments in nuclear radiation detection and imaging enable unprecedented and "smarter" ways to detect, map, and visualize nuclear radiation. The recently developed concept of three-dimensional (3-D) Scene-data fusion allows us now to "see" nuclear radiation in three dimensions, in real time, and specific to radionuclides. It is based on a multi-sensor instrument that is able to map a local scene and to fuse the scene data with nuclear radiation data in 3-D while the instrument is freely moving through the scene. This new concept is agnostic of the deployment platform and the specific radiation detection or imaging modality. We have demonstrated this 3-D Scene-data fusion concept in a range of configurations in locations, such as the Fukushima Prefecture in Japan or Chernobyl in Ukraine on unmanned and manned aerial and ground-based platforms. It provides new means in the detection, mapping, and visualization of radiological and nuclear materials relevant for the safe and secure operation of nuclear and radiological facilities or in the response to accidental or intentional releases of radioactive materials where a timely, accurate, and effective assessment is critical. In addition, the ability to visualize nuclear radiation in 3-D and in real time provides new means in the communication with public and facilitates to overcome one of the major public concerns of not being able to "see" nuclear radiation.

Piezoelectric micromachined ultrasonic transducer (pMUT) rangefinders have been rapidly developed in the last decade. With high output pressure to enable long-range detection and low power consumption (16 μW for over 1 m range detection has been reported), pMUT rangefinders have drawn extensive attention to mobile range-finding. pMUT rangefinders with different strategies to enhance range-finding performance have been developed, including the utilization of pMUT arrays, advanced device structures, and novel piezoelectric materials, and the improvements of range-finding methods. This work briefly introduces the working principle of pMUT rangefinders and then provides an extensive overview of recent advancements that improve the performance of pMUT rangefinders, including advanced pMUT devices and range-finding methods used in pMUT rangefinder systems. Finally, several derivative systems of pMUT rangefinders enabling pMUT rangefinders for broader applications are presented.

Linear frequency modulated continuous wave (LFMCW) radar has been applied to the field about short-range target detection. In this article, in order to achieve the low cost and general short-range target detection, a semi-physical LFMCW radar system is designed to estimate the distance and speed of the moving target in real scenarios. Meanwhile, the received echo signal is processed by using sparse Fourier transform and fast Fourier transform so as to further improve computational efficiency. Experimental results confirm the effectiveness of the designed semi-physical LFMCW radar system. More importantly, the designed system also lays the foundation for the future engineering application for the LFMCW radar. [ABSTRACT FROM AUTHOR]

Polarimetric information is of great importance for radar target recognition. Conventional polarimetric features are hand-designed based on scattering mechanism. In this study, a novel polarimetric target recognition framework based on long–short-term memory (LSTM) network is proposed. The different polarimetric channels are regarded as the sequential inputs in LSTM, and the features are extracted automatically. Experimental results on dual-polarised high-resolution range profile recognition demonstrate that the features learnt by LSTM are more discriminating than conventional features. The recognition performance of the proposed method outperforms the state-of-the-art methods as well. [ABSTRACT FROM AUTHOR]

Most existing algorithms in high-resolution range profile recognition focus on the closed set cases, where the test sample is from a known class. However, a sample could be drawn from unknown classes in realistic scenario, which is named as open set recognition. Here, open set HRRP recognition is achieved by incorporating extreme value theory into convolutional neural network. The softmax layer is replaced by a so-called openmax layer which estimates probabilities of the test sample belonging to known and unknown classes. Experimental results demonstrate that the proposed method outperforms the state-of-art algorithms such as NN, 1-vs-set machine, and W-SVM in terms of correct rejection rate. [ABSTRACT FROM AUTHOR]

Costas arrays are widely used in radar waveform design, especially for frequency-coding signal design. Among all the construction methods, exhaustion method requires many calculations, making it time-consuming to generate Costas arrays with large orders. Many algebraic construction methods for Costas arrays, which require fewer calculations, are developed. Among these methods, Welch construction method is easy to achieve and thus widely used. However, Welch construction method is ineffective for Costas arrays with certain orders on system based on IEEE standard, such as 40 and 42, which should be effective in theory. Through conducting further researches that indicate Welch construction method is ineffective due to the exponential increase of intermediate variables, this study discusses this problem and develops a new arithmetic to solve it. [ABSTRACT FROM AUTHOR]

The non-linear filter is subject to divergence for close-range target tracking; an adaptive best linear unbiased estimation (BLUE) filter with fused range estimation is presented. After proposing the notion of predicted range, the weighted estimation of the predicted and measured ranges is used in the converted measurement model to track the target. The adaptive BLUE filtering parameters with Rayleigh range measurement are derived. Simulation results show the adaptive BLUE filter exhibits better robustness and accuracy with modest computational burden. [ABSTRACT FROM AUTHOR]

SAR raw data missing occurs when radar is interrupted for various reasons. In order to deal with this problem, a method is proposed to focus the missing SAR raw data via stage-wise orthogonal matching pursuit (StOMP). A reference function in time domain is designed for the missing raw data. After matched with the reference function, the energy of missing raw data is concentrated in two-dimensional frequency domain. Then, StOMP algorithm is available to recover the matched raw data in two-dimensional frequency domain. The recovered raw data is available to be processed with traditional SAR imaging algorithms. The Omega-K algorithm is chosen to deal with the recovered raw data in experiments. Point target and area target simulations are carried out to validate the effectiveness of the proposed method for azimuth missing SAR raw data. The data missing rate is 50% in both point and area target simulation. The resolution of point targets can reach 0.3 m in both range and azimuth direction. [ABSTRACT FROM AUTHOR]

The range profile of the plasma sheath target is always found to be distorted when using the linear frequency modulation signal as the radar detection signal. As a result, the detection and tracking of the target became hard, or even failure. Here, three possible reasons of the range profile distortion is investigated in detail: (i) The broadening of the particles in the radial direction of the radar detection when the plasma sheath is produced; (ii) The scatterers in one range gate have different radial velocities that the range profile is dispersion due to the range-Doppler coupling effect; (iii) The amplitude and frequency of the echo signal are modulated by the time-varying plasma sheath. Here, the influence of the above three mechanisms on the range profile is simulated. In addition, for the accurate detection and tracking of these targets, the reason of the distortion should be distinguished. Therefore, several methods are proposed to distinguish the different mechanisms for the range profile distortion. [ABSTRACT FROM AUTHOR]

It is well-known that the noise jamming impedes the mission effectiveness of radar systems. It raises the level of the background and swamps out target returns. Techniques to suppress jamming and improve the performance of radar systems are continuously being developed. Here, a jammer being close to a target or even equivalent to it in direction, colloquially referred to as mainlobe jamming is considered. A mainlobe jamming cancellation technique based on multi-static radar systems (MSRSs) is developed. In a MSRS, a jammer will produce different time delays and relative speeds to the diverse radar receivers located at separated positions. Here, the method to simultaneously estimate the shifts of time delay and Doppler frequency in the range-Doppler plane (RDP) is proposed. Furthermore, the jamming cancellation is adaptively performed in the range-Doppler domain. The simulation results show the validity of the proposed method. [ABSTRACT FROM AUTHOR]

This study develops a robust method for ship target recognition, based on inverse synthetic aperture radar (ISAR) image matching with the template of 3D model. To deal with the difficulty of building template lib, the authors develop to use CAD model instead of the live radar data, which can be projected to the range–Doppler plane at any angle. In the study, the method of matching between the observed ISAR image and candidate target image of model is also proposed, including feature extraction and scoring for recognition. In addition, influences of estimation accuracy for projection are analysed and simulated. Finally, recognition results obtained with simulated data are provided to verify the effectiveness of the proposed approach. [ABSTRACT FROM AUTHOR]

Simultaneous Localization and Mapping (SLAM) is an active area of robot research. SLAM with a laser range finder (LRF) is effective for localization and navigation. However, commercial robots usually have to use low-cost LRF sensors, which result in lower resolution and higher noise. Traditional scan-matching algorithms may often fail while the robot is running too quickly in complex environments. In order to enhance the stability of matching in the case of large pose differences, this paper proposes a new method of scan-matching mainly based on Fast Fourier Transform (FFT) as well as its application with a low-cost LRF sensor. In our method, we change the scan data within a range of distances from the laser to various images. FFT is applied to the images to determine the rotation angle and translation parameters. Meanwhile, a new kind of feature based on missing data is proposed to determine the rough estimation of the rotation angle under some representative scenes, such as corridors. Finally, Iterative Closest Point (ICP) is applied to determine the best match. Experimental results show that the proposed method can improve the scan-matching and SLAM performance for low-cost LRFs in complex environments. [ABSTRACT FROM AUTHOR]

This study discusses the capability of the orthogonal frequency division multiplexing (OFDM) radar recognition on the aircraft in the chaff jamming, in contrast to the linear frequency modulation (LFM) signal form. The process result of the LFM signal form induces a fake target in the recognition on the aircraft in the chaff jamming, because the range and the Doppler are coupled. The process result of the OFDM signal form can separate the real target and the chaffs clearly, because the range and the Doppler are uncoupled from the signal form. The OFDM signal form is a novel and efficient way to solve the chaff jamming. [ABSTRACT FROM AUTHOR]

Abstract If scanning total stations (TLS+TS) are used in scanning mode for high accurate engineering applications, the systematic influence of the incidence angle (IA) on the reflectorless distance measurement has to be eliminated. At present, methods for quantifying the systematic distance deviations under IA are missing because the measured points are not reproducible. In this paper, three such methods are presented. They are conditional on the used instruments and the required accuracy. These methods are validated with respect to specified framework conditions. The distance deviations are derived in all three methods as difference between the distance measured with TLS+TS in the scanning mode (D TLS) and the corresponding reference distance (D ref). The D ref is determined in three steps: measurement of a high accuracy network, measurement for determining the starting point of the D ref ; object measurement to determine the endpoints of D ref. The corresponding D TLS and D ref are identified by means of the horizontal direction Hz (Hz TLS and Hz ref) and the vertical angle V (V TLS and V ref), both pairs of angles referring to the same origin marked by the axis of the common coordinate system. Depending on the used method, the D ref is determined with a standard uncertainty of 0.1–0.3 mm (at a distance of 30 m). The quantified influence of IA on the distance measurement of the Leica MS50 at a distance of 30 m to a granite plate varies in the interval of 0.8 mm. The strong variation due to the IA occurs from 0 to 20 gon, its effect is stable from 20 to 60 gon. [ABSTRACT FROM AUTHOR]

The enormous advances in sensing and data processing technologies in combination with recent developments in nuclear radiation detection and imaging enable unprecedented and “smarter” ways to detect, map, and visualize nuclear radiation. The recently developed concept of three-dimensional (3-D) Scene-data fusion allows us now to “see” nuclear radiation in three dimensions, in real time, and specific to radionuclides. It is based on a multi-sensor instrument that is able to map a local scene and to fuse the scene data with nuclear radiation data in 3-D while the instrument is freely moving through the scene. This new concept is agnostic of the deployment platform and the specific radiation detection or imaging modality. We have demonstrated this 3-D Scene-data fusion concept in a range of configurations in locations, such as the Fukushima Prefecture in Japan or Chernobyl in Ukraine on unmanned and manned aerial and ground-based platforms. It provides new means in the detection, mapping, and visualization of radiological and nuclear materials relevant for the safe and secure operation of nuclear and radiological facilities or in the response to accidental or intentional releases of radioactive materials where a timely, accurate, and effective assessment is critical. In addition, the ability to visualize nuclear radiation in 3-D and in real time provides new means in the communication with public and facilitates to overcome one of the major public concerns of not being able to “see” nuclear radiation.

Stereopsis is the computation of depth information from views acquired simultaneously from different points in space. For many years, stereopsis was thought to be confined to primates and other mammals with front-facing eyes. However, stereopsis has now been demonstrated in many other animals, including lateral-eyed prey mammals, birds, amphibians and invertebrates. The diversity of animals known to have stereo vision allows us to begin to investigate ideas about its evolution and the underlying selective pressures in different animals. It also further prompts the question of whether all animals have evolved essentially the same algorithms to implement stereopsis. If so, this must be the best way to do stereo vision, and should be implemented by engineers in machine stereopsis. Conversely, if animals have evolved a range of stereo algorithms in response to different pressures, that could inspire novel forms of machine stereopsis appropriate for distinct environments, tasks or constraints. As a first step towards addressing these ideas, we here review our current knowledge of stereo vision in animals, with a view towards outlining common principles about the evolution, function and mechanisms of stereo vision across the animal kingdom. We conclude by outlining avenues for future work, including research into possible new mechanisms of stereo vision, with implications for machine vision and the role of stereopsis in the evolution of camouflage. [ABSTRACT FROM AUTHOR]

The results of research and development of a 320 × 240 platinum silicide focal plane array (FPA) for the spectral range of 3-5 μm are presented. The development is based entirely on CMOS technology. It is shown that the FPA makes it possible to adjust the photosignal accumulation time at a fixed frame rate and subtract the background constant component in the output device. [ABSTRACT FROM AUTHOR]

A method of increased measurement accuracy is proposed, along with the corresponding hardware for determining the size of objects and distances to them by analyzing digital photographic imagery. The results of experimental studies are presented. [ABSTRACT FROM AUTHOR]

Analytic relationships for the errors that arise in measurements of the frequency of a harmonic signal of limited duration against a noise background with the use of spectral estimation of frequency and the weighted frequency averaging method are presented. Equality of the minimally attainable values of the error for both methods with equality of the asymptotic rate of decrease of the side lobes of the error envelope is demonstrated. [ABSTRACT FROM AUTHOR]

Reported herein is the design, characterization, and demonstration of a laser interrogation and response optical discrimination system based on large-area corner-cube retroreflective films. The switchable retroreflective films use light-scattering liquid crystal to modulate retroreflected intensity. The system can operate with multiple wavelengths (visible to infrared) and includes variable divergence optics for irradiance adjustments and ease of system alignment. The electronic receiver and switchable retroreflector offer low-power operation (<4 mW standby) on coin cell batteries with rapid interrogation to retroreflected signal reception response times (<15 ms). The entire switchable retroreflector film is <1 mm thick and is flexible for optimal placement and increased angular response. The system was demonstrated in high ambient lighting conditions (daylight, 18k lux) with a visible 10-mW output 635-nm source out to a distance of 400 m (naked eye detection). Nighttime demonstrations were performed using a 1.5-mW, 850-nm infrared laser diode out to a distance of 400 m using a night vision camera. This system could have tagging and conspicuity applications in commercial or military settings. [ABSTRACT FROM AUTHOR]

We present an optical 3-D ranging camera for automotive applications that is able to provide a centimeter depth resolution over a \mbox40^\circ \times \mbox20^\circ field of view up to 45 m with just 1.5 W of active illumination at 808 nm. The enabling technology we developed is based on a CMOS imager chip of 64 $\times$ 32 pixels, each with a single-photon avalanche diode (SPAD) and three 9-bit digital counters, able to perform lock-in time-of-flight calculation of individual photons emitted by a laser illuminator, reflected by the objects in the scene, and eventually detected by the camera. Due to the SPAD single-photon sensitivity and the smart in-pixel processing, the camera provides state-of-the-art performance at both high frame rates and very low light levels without the need for scanning and with global shutter benefits. Furthermore, the CMOS process is automotive certified. [ABSTRACT FROM PUBLISHER]

The laser range finder is one of the most essential sensors in the field of robotics. The laser range finder provides an accurate range measurement with high angular resolution. However, the short range scanners require an additional calibration to achieve the abovementioned accuracy. The calibration procedure described in this work provides an estimation of the internal parameters of the laser range finder without requiring any special three-dimensional targets. This work presents the use of a short range URG-04LX scanner for mapping purposes and describes its calibration. The precision of the calibration was checked in an environment with known ground truth values and the results were statistically evaluated. The benefits of the calibration are also demonstrated in the practical applications involving the segmentation of the environment. The proposed calibration method is complex and detects all major manufacturing inaccuracies. The procedure is suitable for easy integration into the current manufacturing process. [ABSTRACT FROM AUTHOR]

Here, we describe a portable stereo camera system that integrates a GPS receiver, an attitude sensor and 3D stereo photogrammetry to rapidly estimate the position of multiple animals in space and time. We demonstrate the performance of the system during a field test by simultaneously tracking the individual positions of six long-finned pilot whales, Globicephala melas. In shore-based accuracy trials, a system with a 50-cm stereo baseline had an average range estimation error of 0.09 m at a 5-m distance increasing up to 3.2 at 50 m. The system is especially useful in field situations where it is necessary to follow groups of animals travelling over relatively long distances and time periods whilst obtaining individual positions with high spatial and temporal resolution (up to 8 Hz). These positions provide quantitative estimates of a variety of key parameters and indicators for behavioural studies such as inter-animal distances, group dispersion, speed and heading. This system can additionally be integrated with other techniques such as archival tags, photo-identification methods or acoustic playback experiments to facilitate fieldwork investigating topics ranging from natural social behaviour to how animals respond to anthropogenic disturbance. By grounding observations in quantitative metrics, the system can characterize fine-scale behaviour or detect changes as a result of disturbance that might otherwise be difficult to observe. [ABSTRACT FROM AUTHOR]

Rapid sample preparation and measurement protocols for optically stimulated luminescence (OSL) dating have been investigated as a method of increasing the throughput of samples (e.g. Roberts et al. 2009). Here, we investigate the potential of dating samples treated using only hydrochloric acid (HCl) for providing accurate range-finder ages for quartz. The equivalent dose ( D e ) is underestimated for older samples using a standard single-aliquot regenerative-dose (SAR) protocol, but measurement of the post-IR OSL signal (e.g. Roberts and Wintle, 2003) provides D e estimates within 15% of the ‘target fully prepared D e ’ for two-thirds of samples. The application of a standardised growth curve (SGC) is also investigated. For these dune samples, the most efficient preparation and measurement procedure from which accurate D e estimates can be obtained is treatment with HCl-only, measurement of the natural and regenerative post-IR OSL signal, and calculation using a region-independent SGC. A slightly longer protocol incorporating an additional preparation stage of heavy liquid density separation can be used to improve D e estimates in samples where feldspar-contamination is thought to be particularly problematic. In practice, these time savings of days to weeks in the preparation and measurement protocols mean that a large number of samples can first be rapidly treated with HCl, the post-IR blue OSL signal measured using a shortened double-SAR protocol, and D e calculated by applying an independent SGC before then deciding which samples require full preparation and measurement, rather than the inefficiency of committing time and resources to all samples if this is unnecessary for the context of a particular suite of samples. The potential of this rapid preparation and measurement protocol is discussed in relation to sand dune dating studies. [ABSTRACT FROM AUTHOR]

An ultrasonic 3D rangefinder uses an array of AlN MEMS transducers and custom readout electronics to localize targets over a \pm 45^\circ field of view up to 1 m away. The rms position error at 0.5 m range is 0.4 mm, 0.2^\circ, and 0.8^\circ for the range, x-angle, and y-angle axes, respectively. The 0.18 \mum CMOS ASIC comprises 10 independent channels with separate high voltage transmitters, readout amplifiers, and switched-capacitor bandpass \Sigma\Delta ADCs with built-in continuous time anti-alias filtering. For a 1 m maximum range, power dissipation is 400 \muW at 30 fps. For a 0.3 m maximum range, the power dissipation scales to 5 \muW/ch at 10 fps. [ABSTRACT FROM PUBLISHER]

A particularly unusual visual system exists in the visually guided aquatic predator, the Sunburst Diving Beetle, Thermonectus marmoratus (Coleoptera: Dytiscidae). The question arises: how does this peculiar visual system function? A series of experiments suggests that their principal eyes (E1 and E2) are highly specialized for hunting. These eyes are tubular and have relatively long focal lengths leading to high image magnification. Their retinae are linear, and are divided into distinct green-sensitive distal and UV and polarization-sensitive proximal portions. Each distal retina, moreover, has many tiers of photoreceptors with rhabdomeres the long axis of which are peculiarly oriented perpendicular to the light path. Based on detailed optical investigations, the lenses of these eyes are bifocal and project focused images onto specific retinal tiers. Behavioral experiments suggest that these larvae approach prey within their eyes' near-fields, and that they can correctly gauge prey distances even when conventional distance-vision mechanisms are unavailable. In the near-field of these eyes object distance determines which of the many retinal layers receive the best-focused images. This retinal organization could facilitate an unusual distance-vision mechanism. We here summarize past findings and discuss how these eyes allow Thermonectus larvae to be such successful predators. [ABSTRACT FROM AUTHOR]

A new distance-based estimator for forest regeneration assessment, the mean distance method, was developed by combining ideas and techniques from the wandering quarter method, T-square sampling and the random pairs method. The performance of the mean distance method was compared to conventional 4.05 square meter plot sampling through simulation analysis on 405 square meter blocks of a field surveyed clumped distribution and a computer generated random distribution at different levels of density of 100, 50 and 25%. The mean distance method accurately estimated density on the random populations but the mean distance method estimates were more variable than those of 4.05 square meter plot sampling. The mean distance method overestimated actual density and was less precise than plot sampling when both methods were tested on the clumped populations. The optimum sample sizes needed for the mean distance method to achieve the same precision as 4.05 square meter plot sampling at all three density levels, for both the random and clumped spatial distributions, were at least 10 times larger than the sample size used for 4.05 square meter plot sampling. [ABSTRACT FROM AUTHOR]

Endocrine-disrupting chemicals with estrogenic activity (EA) or anti-EA (AEA) have been extensively reported to possibly have many adverse health effects. We have developed robotized assays using MCF-7:WS8 cell proliferation (or suppression) to detect EA (or AEA) of 78 test substances supplied by the Interagency Coordinating Committee on the Validation of Alternative Methods and the National Toxicology Program’s Interagency Center for the Evaluation of Alternative Toxicological Methods for validation studies. We also assayed ICI 182,780, a strong estrogen antagonist. Chemicals to be assayed were initially examined for solubility and volatility to determine optimal assay conditions. For both EA and AEA determinations, a Range-Finder assay was conducted to determine the concentration range for testing, followed by a Comprehensive assay. Test substances with potentially positive results from an EA Comprehensive assay were subjected to an EA Confirmation assay that evaluated the ability of ICI 182,780 to reverse chemically induced MCF-7 cell proliferation. The AEA assays examined the ability of chemicals to decrease MCF-7 cell proliferation induced by nonsaturating concentrations of 17β-estradiol (E2), relative to ICI or raloxifene, also a strong estrogen antagonist. To be classified as having AEA, a saturating concentration of E2 had to significantly reverse the decrease in cell proliferation produced by the test substance in nonsaturating E2. We conclude that our robotized MCF-7 EA and AEA assays have accuracy, sensitivity, and specificity values at least equivalent to validated test methods accepted by the U.S. Environmental Protection Agency and the Organisation for Economic Co-operation and Development. [ABSTRACT FROM AUTHOR]

Abstract: A compact, Q-switched fibre laser is proposed and demonstrated using a compact Bismuth-based erbium doped fibre (Bi-EDF) together with a Graphene Oxide (GO) Saturable Absorber (SA). The 21cm long Bi-EDF has an erbium dopant concentration of 6300ppm with absorption rates of about 83 and 133dB/m at 1480 and 1530nm. The SA is fabricated from graphene flakes dissolved in water, forming a GO film that is sandwiched between two FC/PC connectors. The Q-switched Bi-EDF laser has an Amplified Spontaneous Emission (ASE) spectrum of 120nm, stretching from 1490 to 1610nm and a Q-switching threshold power of about 65mW. At the maximum pump power of 118mW, the pulses are generated with an average output power and pulse energy of 0.11mW and 4.3nJ, with a repetition rate and pulse width of 27.2kHz and 7.7μs. The output can be tuned over the amplified spontaneous emission spectrum with an average peak power of about −16.8dBm, and observation under a radio frequency spectrum analyser shows a highly stable output at 21.8kHz. The proposed Bi-EDF laser will have substantial uses in applications requiring short and stable pulses such as rangefinding and sensing. [Copyright &y& Elsevier]

Previous studies of verbal probabilities have tried to place expressions likea chance,possible, andcertainon 0–1 numerical probability scales. We ask instead, out of a range of outcomes, which outcome a verbal probability suggests. When, for instance, a sample of laptop batteries lasts from 1.5 to 3.5 hours, what is acertainand what is apossibleduration? Experiment 1 showed that speakers associatecertainwith low values andpossiblewith (unlikely) high or maximal values. In Experiment 2, this methodology was applied to several positive and negative verbal probability phrases, showing a preference for high rather than low or middle values in a distribution. Experiment 3 showed that such maxima are not universally described by large numbers. For instance, maximum speed is often described in terms of a small number of time units. Whatcan(possibly) happen is accordingly sometimes described with very low and sometimes with very high values, depending upon focus of interest. Finally, participants in Experiment 4 were given the role of hearers rather than speakers and were asked to infer outcome ranges from verbal probabilities. Hearers appeared to be partly aware of speakers' tendencies to describe outcomes at the top of the range. [ABSTRACT FROM PUBLISHER]