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Aggregate morphological characteristics, including shape, angularity, and surface texture, have a significant impact on the engineering properties of construction materials such as hot-mix asphalt and hydraulic cement concrete. Consequently, the quantification of morphological characteristics of aggregates is essential for quality control of both aggregate production and pavement construction. Imaging techniques provide a cost-effective means for measuring the aggregate morphological characteristics conveniently without tedious work. However, these imaging techniques adopt various mathematical methods with different instrument setups and result in different definitions of morphological descriptors that are usually incomparable with each other. This paper evaluates prevalent imaging techniques used for aggregate morphological characteristics analysis, including equipment cost, repeatability, reliability, accuracy, and measured morphological parameters. Three imaging techniques (second-generation Aggregate Imaging Measurement System, first-generation University of Illinois aggregate image analyzer, and Fourier transform interferometer system), are further evaluated by comparing the analysis results of seven types of aggregates passing a ¾-in. sieve and retained on a ½-in. sieve with manual measurements and visual rankings. Analysis of variance between measurements using different methods is also conducted to evaluate the accuracy of each aggregate imaging system. From the data analysis, recommendations that depend on morphological characteristics of most interest to engineers are made for the selection of appropriate imaging-analysis techniques.

Animal-vehicle collisions (AVCs), and deer-vehicle collisions (DVCs) in particular, are a major safety problem on roads in Virginia, United States. Mitigation measures such as improved fencing and location-specific driver alerts are being implemented and evaluated in Virginia and elsewhere. One of the most promising mitigation methods uses a buried cable animal detection system (BCADS) to provide roadside or in-vehicle warnings to approaching drivers based on the active presence of an animal on or near the roadway. In this study, the Virginia Department of Transportation (VDOT) in collaboration with the Virginia Tech Transportation Institute (VTTI) implemented and monitored the performance of a BCADS on a public road to provide a real-world assessment of system capabilities and possible operation issues. Concurrently, a flashing light “Deer Crossing” warning sign was installed at the site and linked with the BCADS to alert approaching drivers when an animal crossing was detected. Continuous video surveillance data were collected for a year to monitor animal movement, vehicle traffic, and system performance. Study findings indicate that the BCADS is capable of detecting larger animals such as deer, and sometimes smaller animals such as coyotes, with almost 99% reliability. The system also performed well when covered by approximately 0.6 m (2 ft) of snow. Vehicle speed and brake light application data collected during warning sign activation showed that approximately 80% of drivers either braked or slowed in response, indicating that the sign was effective. A 75% reduction in deer-vehicle crashes was observed in the first year after system deployment.

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Due to the appearance of COVID-19 in 2019, person-to-person interactions were drastically reduced. The impact of these restrictions on the economic environment was significant. For example, technical assistance for commissioning or adjusting the parameters of some complex machines/installations had to be postponed. Economic operators became interested in the possibility of remote collaboration, depending on the manufactured products and the performance of the production lines that they owned. This bibliographic research was undertaken to address these needs. The purpose of this review was to analyze the current solutions, approaches, and technologies that workers and specialists can implement to obtain a reliable remote collaboration system. This survey focuses on techniques, devices, and tools that are being used in different contexts to provide remote guidance. We present communication cues and methods being employed, the implemented technological support, and the areas that benefit from remote collaboration. We hope that our effort will be useful to those who develop such systems and people who want to learn about the existence of collaborative solutions, and that it will increase awareness about the applications and the importance of the domain. We are convinced that, with the development of communication systems, the advancement of remote support systems will be a goal for many economic operators.