Search

Background: Falls are a worrying and growing phenomenon worldwide that especially affects the elderly. With the development of technology, one way of studying the real-life falls that occur in healthcare settings is by using video cameras. Aims: To (a) map the patterns of the research on real-life falls among older adults in healthcare settings as assessed with digital video camera supports; and (b) highlight the advances, the evidence produced, and the gaps still present regarding the biomechanics of falls as assessed technologically. Methods: A scoping review following the Preferred Reporting Items for Systematic Reviews and Meta-Analyses extension for Scoping Reviews. CINAHL, PubMed and Google Scholar were searched. All studies regarding falls investigated with video cameras among older individuals in healthcare settings published from 1st January 1990 to 1st January 2022 were eligible. Findings were summarised according to the Patterns, Advances, Gaps, Evidence and Recommendations framework for Scoping Reviews. Results: In total, 1943 studies were retrieved, and 16 met the inclusion criteria. Studies were mostly conducted in Canada. They described the real-life falls that occurred mainly in common and living areas of long-term facilities among older individuals, mainly females. Thirteen studies investigated falls through biomechanics, while three provided advances in the reliability of the measures as collected with video cameras. Studies reported that the biomechanics of a fall, reflecting the direction of the fall and protective responses, increase or decrease the likelihood of serious impact. In addition, the direction of the landing after a fall has been determined as having a significant impact on the severity and outcome of the fall. Conclusion: The use of video cameras to investigate the biomechanics of falls is a well-established research area that offer interesting insight regarding (a) how to prevent falls and their injuries and (b) the direction of the research in the field of falls. [ABSTRACT FROM AUTHOR]

New technologies are being used to facilitate the recognition process during and after earthquakes. These advanced tools are essential to keep track of what is left from of the destruction suffered by the built stock. Among the new technologies are video recordings captured during seismic events, footage from drones, and satellite imagery acquired before and after the event. This review paper presents a series of examples collected from the 2023 Türkiye–Syria earthquakes to illustrate how these new technologies offer a unique and efficient way to capture, document, and transfer information among experts in seismology, earthquake engineering, and disaster management. Whenever possible, these examples are accompanied by simple qualitative explanations to enhance understanding. To demonstrate the potential of video cameras and drone imagery for quantitative analysis, in addition to the various simple examples provided, two case studies are provided—one on road blockages, and another on intensity assessment and wave attenuation as observed in video cameras. These technologies are critical and merit considerable focus, particularly video cameras, which have not received much attention recently, on helping to understand seismic wave passage and their impact on the built environment. Enhancing our use of video cameras in this context can significantly contribute to the sustainability and resilience of our society. With the rapid advancement of image analysis, we advocate for a collaborative platform for accessing and utilizing imagery materials, aiding current and future generations in analysing the causes of such tragedies. [ABSTRACT FROM AUTHOR]

This paper discusses a new method for measuring and calculating the angle of inclination of a railway support or a contact network support, using an unmanned aerial vehicle flying along a straight path, parallel to the railway track. A review of existing measurement methods is carried out, their advantages and disadvantages are indicated. In the method under consideration, it is proposed to measure angles and distances with six laser scanning rangefinders installed in threes on horizontal and inclined planes on an unmanned aerial vehicle. This allows you to increase the speed and accuracy of determining the angle of inclination of vertical supports. The calculations use the minimum distances from the laser scanning range finder to the top and bottom of the support surface. The formulas use geometric relationships and the cosine theorem to calculate the roll of supports taking into account their taper. Measuring distances and angles three times allows for averaging over them, which significantly increases the accuracy of calculations. A model experiment is carried out on a model of a reinforced concrete contact network support in four orientations. A comparison is made between theoretically calculated and experimentally measured distances and inclination angles. The accuracy of parameter determination complies with regulatory requirements.

In contemporary architectural design, a noticeable trend emerges in the meticulous planning of common areas, with an emphasis on fostering the free movements of users within these areas. It is important to consider the architectural elements that influence user behavior in these environments. Previous studies have delved into the relationship between architecture and user activity, often through questionnaires and activity surveys conducted in arbitrary spaces. However, such data are discontinuous and only capture a portion of the space. Therefore, in this study, continuous and extensive recordings were performed in an arbitrary space using a video camera to capture the entirety of the area. Consequently, we were able to comprehend the relationship between architecture and people's activities and observe the formation of user autonomy through their decisions to rearrange furniture. Furthermore, an "Open Pose" system was used to detect people and generate a user stay distribution chart. This was achieved by converting it into a plan view using perspective projection transformation, thereby obtaining objective data automatically. Consequently, we verified the feasibility of conducting visually comprehensible processing using tools like "Open Pose", which was used in one segment of the experiment. [ABSTRACT FROM AUTHOR]

Eruptions of volcanoes and geysers share many fundamental similarities: for example, they are manifestations of Earth’s geothermal energy, involving the pressure-driven expulsion of fluids from the Earth’s interior. However, while volcanoes can produce spectacular lava bubbles that burst, water bubbles are rarely observed on the surface of geysers. It is still unclear why some of these low-viscosity geyser systems produce none, while others produce them regularly. There is no quantification of the size, speed, and height of these bubbles at geysers, which is the gap we fill here. Strokkur creates a water bulge in its surface pool (bulge stage). When the bulge bursts, water is ejected into the air (jet stage). The steam then continues to rise buoyantly and drift away (drift stage). Here we study the evolution of the three stages using records from video camera campaigns and a local seismic network. We find that larger bulges are associated with larger ascent velocities and cause larger jet heights. As energy is channeled into a high jet, small seismic ground motions are recorded. The bulge formation itself is barely visible seismically. Our work suggests that the 0.74±0.27 s-long bulge stage can be used as a first-order proxy for predicting eruption height. This study might also be relevant for understanding fluid dynamics in volcanic systems.

Video camera, are installed on platforms of gyroscopic stabilization systems in order to improve the quality of visual information and provide the required orientation of the optical axis. The goal of the work was to develop a mathematical description that allows evaluating accuracy of gyroscopic stabilization systems for a video camera on a moving object, built on micromechanical sensors for primary information. A biaxial system for gyroscopic stabilization of a video camera on a moving object is considered. A mathematical description of the channel of the stabilization system with control over angle and angular velocity is given. Measuring the angle of deviation of the platform from the horizontal plane and its angular velocity is provided by micromechanical accelerometers and gyroscopes, respectively. Physical nature of the synchronous errors' occurrence in the stabilization system during angular vibrations of a moving object is explained. An assessment of the synchronous error of the stabilization system when the object oscillates with a frequency of 30 Hz is given. An analytical relationship is presented for estimating of the stabilization system errors is caused by random errors of gyroscopes and accelerometers. It is shown that if the platform is stabilized only by gyroscope signals containing random errors such as white noise in the measurements, this will lead to the platform drifting with a standard deviation proportional to the square root of time. In this case, the constant disturbing moment is not processed. A mathematical description of the “blurring” of the video camera image during platform vibrations caused by random errors in inertial sensors is given. Effect of image blur for various platform oscillation parameters is illustrated.

Recently, the autonomous driving industry in China has been gradually shifting its focus from individual-vehicle intelligence to vehicle‒infrastructure cooperation. This shift has brought significant opportunities for the intelligent transportation industry. Although research on vehicle‒infrastructure cooperative sensing is still in its early stage in China, it shows a strong dedication to technological innovation, indicating significant potentials for future growth. This study examines the development status of vehicle‒infrastructure cooperative sensing and thoroughly explores the characteristics and status of core technologies that support vehicle‒infrastructure cooperative sensing. It discusses ongoing advancements in this field, investigates future technology trends, and proposes a range of recommendations for further development. Research indicates that vehicle‒infrastructure cooperative sensing is evolving toward the integration of multi-source data. Presently, its development directions mainly focus on the optimization of pure visual cooperative sensing, upgrades in LiDAR point cloud processing, advancements in multi-sensor spatiotemporal information matching and data fusion, as well as the establishment of a standards system for vehicle‒infrastructure cooperative sensing technologies. To further boost the rapid growth of vehicle‒infrastructure cooperation in China, increasing investment in the research and development of relevant technologies is advised. Enhancing partnerships among different industry sectors, establishing unified standards for processing perception data, and expediting the broad application of these technologies are also key recommendations. These strategies aim to position China advantageously in the global market of autonomous driving, contributing to the sustainable development of the industry.

The problem of optimizing the choice of parameters for installing a video camera, such as the location and viewing angles, tilt and pan to increase the information content of the generated video signal, is considered. The relevance of the paper is due to the lack of methods and programs for automating the process of choosing these parameters. The problem is solved when the pixel density is reached, which is necessary for solving the task of observation. It is based on the proposed model for representing view areas, surveillance and camera locations as discrete sets in accordance with the observation task being solved, which determines the required minimum pixel density as well as selected criteria and restrictions. It gives the opportunity to solve the problem programmatically, unlike existing solutions that use empirical approaches. The main and additional criteria as well as limitations are formulated according to which it is possible to optimize the position of the camera relative to the required surveillance area — the observation task to be solved, the minimum required camera resolution and the maximum information content of the generated image. Algorithms for calculating estimates of the near, far and side boundaries of the view area as well as view angles, pan and tilt are formulated. The adequacy of the proposed model to real areas of observation, review and location of cameras is substantiated. An example of solving an optimization problem is given, which confirms the correctness of using the proposed method. The results obtained make it possible to automate the design process and minimize the influence of the human factor when choosing the location and installation parameters of cameras in the process of designing surveillance systems. The results of the work can be used in the development of algorithms and programs for computer-aided design of surveillance systems.

With advances in bio-logging technology, the posture of animals is now commonly described by inertial measurement units, which include tri-axial accelerometers to estimate pitch and roll angles. Many large seabirds use dynamic soaring flight to travel long distances, but this low-cost flight mode results in high centripetal acceleration, which obscures posture derived from accelerometers. Tri-axial magnetometers are not influenced by acceleration and might provide a way to estimate the posture of animals that experience high centripetal acceleration. We propose a new method to estimate the posture of dynamic soaring seabirds using tri-axial magnetometer data, with the assumption that they do not have large pitch angles during routine flight. This method was field-tested by deploying a combination of bio-logging devices on three albatross species breeding on Marion Island, using bird-borne video loggers to validate the roll angles. Validated data showed that the method worked well in most instances, but accuracy decreased when the heading was close to magnetic north or south. Accurate, fine-scale posture estimates may provide insight into dynamic soaring flight and allow estimates of fine-scale tracks using dead-reckoning, not only for seabirds, but potentially for other species where centripetal acceleration limits the use of accelerometers to estimate posture.

In contemporary architectural design, a noticeable trend emerges in the meticulous planning of common areas, with an emphasis on fostering the free movements of users within these areas. It is important to consider the architectural elements that influence user behavior in these environments. Previous studies have delved into the relationship between architecture and user activity, often through questionnaires and activity surveys conducted in arbitrary spaces. However, such data are discontinuous and only capture a portion of the space. Therefore, in this study, continuous and extensive recordings were performed in an arbitrary space using a video camera to capture the entirety of the area. Consequently, we were able to comprehend the relationship between architecture and people’s activities and observe the formation of user autonomy through their decisions to rearrange furniture. Furthermore, an “Open Pose” system was used to detect people and generate a user stay distribution chart. This was achieved by converting it into a plan view using perspective projection transformation, thereby obtaining objective data automatically. Consequently, we verified the feasibility of conducting visually comprehensible processing using tools like “Open Pose”, which was used in one segment of the experiment.

During earthworks, monitoring and controlling the actual productivity of construction machines enables insight into the progress of tasks, calculation of expected duration and costs, favorable use and allocation of machines, and the application of appropriate decisions and corrective measures, which is of great interest to contractors. Excavators and tipper trucks are primarily used in earthworks. Manual collection of data from the construction site to assess the actual productivity of machines is today considered an outdated, time-consuming, and subjective method. Therefore, audio–visual and sensing technology devices are replacing manual data collection. The paper aims to propose an innovative protocol for optimal recording/tracking of the work of excavators and tipper trucks using audio–visual (a video camera or smartphone) and location-sensing technology (GPS). The protocol proposal enables a precise statement of the time cycle of excavators and tipper trucks and an estimate of their actual productivity. The application of the protocol proposal on the construction site demonstrated its practicality and functionality. [ABSTRACT FROM AUTHOR]

A camera-based visiometer is a promising atmospheric visibility measurement tool because it can meet some specific demands such as the need for visibility monitoring in a strong way, whereas traditional instruments, such as forward scatter-type sensors and transmissometers, can hardly be widely utilized due to their high cost. The camera-based method is used to measure visibility by recording the luminance contrast of the objects in an image. However, lacking standard conditions, they can hardly obtain absolute measurements even with blackbody objects. In this paper, the errors caused by nonstandard conditions in camera-based visiometers with two artificial black bodies are analyzed. The results show that the luminance contrasts of the two blackbodies are highly dependent on the environmental radiance distribution. The nonuniform sky illuminance can cause a large error in the blackbody contrast estimations, leading to substantial visibility measurement errors. A method based on a support vector machine (SVM) is proposed to classify the visibility under nonstandard conditions to ensure the reliability of the camera-based visiometer. A classification accuracy of 96.77% was achieved for the data containing images depicting different illumination conditions (e.g., a clear sky, cloudy sky, and overcast). The results show that the classifier based on the SVM is an effective and reliable method to estimate visibility under complex conditions. [ABSTRACT FROM AUTHOR]

Modern video surveillance systems (VSS) can recognize a person and her/his activity. A particular example of such a VSS system is the monitoring and support of human health and wellbeing during exercise with sports equipment. In this work-inprogress paper, a prototype of the VSS system is demonstrated for monitoring the movement of a person around the sport training machine. For the recognition problem we consider the following situations: a) training machine is free (no person is close to the machine); b) a person is in the area near the training machine (but not in the working area); c) a person is in the working area of training machine (but the training machine is not used); d) a person is working on the training machine. Our early experimental study evaluates the feasibility of such a VSS system.

To cope with heat stress, storks wet their legs by excreting on them, known as urohidrosis, and perform wing-spreading in which the wings are half extended in the form of an inverted triangle. While several studies have highlighted the role of urohidrosis as an important cooling mechanism and suggested a possible thermoregulatory function of wing-spreading, sex-based comparisons and trends of these behaviours throughout the breeding season remain unexplored. Here we explore thermoregulation in a wild population of Painted Storks (Mycteria leucocephala) nesting in the National Zoological Park, Delhi, India, through the non-invasive videography technique. Temperature, humidity and wind speed significantly influenced both urohidrosis and wing-spreading behaviours. Male storks exhibited higher rates of urohidrosis and spend more time wing-spreading compared to females. Seasonal and diurnal differences were observed with more urohidrosis and wing-spreading during the hottest hours of the day and early part of the nesting season in August-September. The rate of both behaviours declined as the nesting season progressed till November when ambient temperatures dropped., (Copyright © 2024. Published by Elsevier B.V.)

BackgroundThe quality of neonatal resuscitation after delivery needs to be improved to reach the Sustainable Development Goals 3.2 (reducing neonatal deaths to

A camera-based visiometer is a promising atmospheric visibility measurement tool because it can meet some specific demands such as the need for visibility monitoring in a strong way, whereas traditional instruments, such as forward scatter-type sensors and transmissometers, can hardly be widely utilized due to their high cost. The camera-based method is used to measure visibility by recording the luminance contrast of the objects in an image. However, lacking standard conditions, they can hardly obtain absolute measurements even with blackbody objects. In this paper, the errors caused by nonstandard conditions in camera-based visiometers with two artificial black bodies are analyzed. The results show that the luminance contrasts of the two blackbodies are highly dependent on the environmental radiance distribution. The nonuniform sky illuminance can cause a large error in the blackbody contrast estimations, leading to substantial visibility measurement errors. A method based on a support vector machine (SVM) is proposed to classify the visibility under nonstandard conditions to ensure the reliability of the camera-based visiometer. A classification accuracy of 96.77% was achieved for the data containing images depicting different illumination conditions (e.g., a clear sky, cloudy sky, and overcast). The results show that the classifier based on the SVM is an effective and reliable method to estimate visibility under complex conditions.

Light emitting diodes (LED) are becoming the dominant lighting elements due to their efficiency. Optical camera communications (OCC), the branch of visible light communications (VLC) that uses video cameras as receivers, is a suitable candidate in facilitating the development of new communication solutions for the broader public because video cameras are available on almost any smartphone nowadays. Unfortunately, most OCC systems that have been proposed until now require either expensive and specialized high-frame-rate cameras as receivers, which are unavailable on smartphones, or they rely on the rolling shutter effect, being sensitive to camera movement and pointing direction, they produce light flicker when low-frame-rate cameras are used, or they must discern between more than two light intensity values, affecting the robustness of the decoding process. This paper presents in detail the design of an OCC system that overcomes these limitations, being designed for receivers capturing 120 frames per second and being easily adaptable for any other frame rate. The system does not rely on the rolling shutter effect, thus making it insensitive to camera movement during frame acquisition and less demanding about camera resolution. It can work with reflected light, requiring neither a direct line of sight to the light source nor high resolution image sensors. The proposed communication is invariant to the moment when the transmitter and the receiver are started as the communication is self-synchronized, without any other exchange of information between the transmitter and the receiver, without producing light flicker, and requires only two levels of brightness to be detected (light on and light off). The proposed system overcomes the challenge of not producing light flicker even when it is adapted to work with very low-frame-rate receivers. This paper presents the statistical analysis of the communication performance and discusses its implementation in an indoor localization system. [ABSTRACT FROM AUTHOR]

The aim of this study is to quantify potential systemic timing bias between fully automatic timing (FAT) and timing with iPhone camera (Apple Inc., Cupertino, CA, USA) and then consider whether an iPhone can be used as an inexpensive timing system for sprint events at athletics competitions. A flashlight was aimed at FAT camera (Lynx System Developers, Haverhill, MA, USA) and two iPhones, at 120 and 240 frames per second (fps), respectively, so that they could capture the light from it. By turning the flashlight on and off at varying intervals (1–33 s, average 9.5 s), the cameras captured a series of light beams. The time intervals between the start of two light beams were measured 31 times on the recordings from all the cameras. On each recording with the iPhones, two analyses were performed: one where the video image before the light beam (start before light) from the flashlight was set to 0 s and one where the first image with the light beam (start on light) was set to 0 s. Start on light showed no significant time differences compared to FAT. With 240 fps the standard deviation was ± 0.001 s, 29% of the times were the same as FAT, while 81% of the times are within ± 0.001 s. The largest deviation was a time of −0.003 s from FAT. With 120 fps there was a standard deviation of ± 0.003 and a maximum deviation of −0.006 s, where 39% of the times were within ± 0.001 s. At start before light, a significant but expected difference was found with an average deviation of +0.008 s with 120 fps and +0.004 s with 240 fps, with maximum deviations of +0.014 and +0.006 s. It can be concluded that the camera on an iPhone is accurate as we did not find any systematic bias from FAT with start on light. [ABSTRACT FROM AUTHOR]

The common problems faced by students in English speaking are anxiety and the lack of confidence and ideas. This research was conducted to determine the relevant factors and to provide a solution by using the smartphone video camera. To obtain the data in this research, experimental research was performed inside and outside the classroom with a series of treatments and a questionnaire sheet as the instrument. The data were analyzed using a model proposed by Smeda, Dakich, and Sharda (2014) and a Likert scale questionnaire, which was adapted from Spratt, Humphreys, and Chan (2002). The result from the test showed a significant difference between the experimental and control classes as the carried t-test presented the score of -8.36, which was out of the limit (between -1.96 and 1.96). Another result was the students developed positively which was shown by: the anxiety tends to decrease as they were given time before performing thus prepared better, their self-confidence was increased and challenged by using the smartphone video camera method due to the application of innovation in the speaking class. The conclusion of this research is lecturer needs to apply new methods, one of which is using a smartphone application.

The determination of wave runup is important to coastal management, including engineering designs and hazard assessments. In data-sparse regions such as the Caribbean, where critical coastal parameters are lacking for adequate decision-making, optimal use must be made of limited datasets to access continuous wave runup data. A video camera system was established at Mayaro Beach in Trinidad and collected video data for a short duration. The waterline variations were rectified and then digitised by sampling pixel intensities along a cross-shore transect. A wave runup time series of 15-minute duration was generated to represent the selected hour of video, from which statistical wave runup estimates including the maximum runup, Rmax, and the runup exceeded by 2% of swash events, Ru2%, were determined. Numerous expressions exist to estimate runup elevations, with the Stockdon et al. (2006) Ru2% predictor being a good performer. The predictive skill of this formulation was assessed, by comparing the measured and predicted magnitudes of the Ru2% using a calibrated/validated model for wave parameters. For the video data analysed, it was found that the coefficient of determination (R²) and the root mean square error (RMSE) were 0.414 and 0.673m for the Stockdon et al. (2006) predictor, but improved to 0.587 and 0.055m using a modified predictor, respectively. Disparities between predicted and observed values were attributed primarily to site-specific conditions and the lack of concurrent in-situ wave data and beach slope characteristics; these were accounted for using the modified predictor and thus enabled an improved wave runup description at the data-sparse site. [ABSTRACT FROM AUTHOR]

В статье обозначена проблема исследования, связанная с поиском оптимальных путей воспитания, обучения детей с ограниченными возможностями здоровья. Высказывается идея использования робота-манипулятора на занятиях по образовательной робототехнике в коррекционной школе. Приводится подробный алгоритм монтажа учебного робота-манипулятора. Описан один из способов участия детей с нарушениями опорнодвигательного аппарата в занятиях по образовательной робототехнике. Кратко описаны учебные занятия с использованием робота-манипулятора. Предлагается использовать соревновательный подход на занятиях по образовательной робототехнике в коррекционной школе.

Many existing video surveillance solutions are based on sending information between camera and remote server. In this paper, we study video services that are being built in an edge-centric Internet of Things (IoT) environment. Multiple cameras are available. Each video stream is subject to create simple events. Complex events can also be created based on the combination of simple events and context from IoT environment, forming the semantics for video analytics. We introduce microservice-based on step-by-step technology to show how software can be designed and developed for various application areas using multiple cameras. We extend video services that were discussed in our previous works using the developed technology. Proposal smart video services allow to organize smart video monitoring in the following areas: Industrial Internet of Things (IIoT), medicine mHelath services, SmartRoom.

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. [ABSTRACT FROM AUTHOR]

The article presents a design solution of a mobile robot dedicated to autonomous movement in hard-to-reach places. The 3D printing technology made it possible to make a mechanical structure adapted to the actuators and electronic elements with which the robot was equipped. To control the mobile robot, a Raspberry Pi 2 microcomputer and an Atmega328P microcontroller were used, which allows the robot to be controlled via WiFi or a game controller for PlayStation3 using Bluetooth communication. In addition to remote control, the rover has an implemented algorithm of autonomous operation with simultaneous image transmission. [ABSTRACT FROM AUTHOR]

Computer simulation of a panoramic three-range catadioptric system (lens) of a navigation video camera for unmanned miniature drones is performed. The optical system uses a three-channel radiation receiver sensitive in three spectral regions. [ABSTRACT FROM AUTHOR]

Light emitting diodes (LED) are becoming the dominant lighting elements due to their efficiency. Optical camera communications (OCC), the branch of visible light communications (VLC) that uses video cameras as receivers, is a suitable candidate in facilitating the development of new communication solutions for the broader public because video cameras are available on almost any smartphone nowadays. Unfortunately, most OCC systems that have been proposed until now require either expensive and specialized high-frame-rate cameras as receivers, which are unavailable on smartphones, or they rely on the rolling shutter effect, being sensitive to camera movement and pointing direction, they produce light flicker when low-frame-rate cameras are used, or they must discern between more than two light intensity values, affecting the robustness of the decoding process. This paper presents in detail the design of an OCC system that overcomes these limitations, being designed for receivers capturing 120 frames per second and being easily adaptable for any other frame rate. The system does not rely on the rolling shutter effect, thus making it insensitive to camera movement during frame acquisition and less demanding about camera resolution. It can work with reflected light, requiring neither a direct line of sight to the light source nor high resolution image sensors. The proposed communication is invariant to the moment when the transmitter and the receiver are started as the communication is self-synchronized, without any other exchange of information between the transmitter and the receiver, without producing light flicker, and requires only two levels of brightness to be detected (light on and light off). The proposed system overcomes the challenge of not producing light flicker even when it is adapted to work with very low-frame-rate receivers. This paper presents the statistical analysis of the communication performance and discusses its implementation in an indoor localization system.

Scaffolding serves as one construction trade with high importance. However, scaffolding suffers from low productivity and high cost in Australia. Activity Analysis is a continuous procedure of assessing and improving the amount of time that craft workers spend on one single construction trade, which is a functional method for monitoring onsite operation and analyzing conditions causing delays or productivity decline. Workface assessment is an initial step for activity analysis to manually record the time that workers spend on each activity category. This paper proposes a method of automatic scaffolding workface assessment using a 2D video camera to capture scaffolding activities and the model of key joints and skeleton extraction, as well as machine learning classifiers, were used for activity classification. Additionally, a case study was conducted and showed that the proposed method is a feasible and practical way for automatic scaffolding workface assessment. [ABSTRACT FROM AUTHOR]

• POLEMAD is the first relational database containing multimodal speech data for Polish language obtained from electromagnetic articulograph, multichannel audio recorder and stereoscopic vision system. • Containing speech samples from 20 subjects, the database is one of the largest datasets of this type in the world. • A new type of images obtained from an acoustic camera is stored in the POLEMAD database. • The database can facilitate experiments on speech inversion including dynamic Bayesian networks. The structure and functionality of the POLEMAD database constructed on the basis of a study using Electromagnetic Articulograph AG 500, an acoustic camera, and 3 video cameras are described in the paper. The article describes also data types stored in the database including speaker data, EMA data, video and sound recordings, phonetic information, and dynamic Bayesian network (DBN) models. The database allows for selective extraction of various types of samples for further analysis, which is performed by SQL queries generated in MATLAB® using Database Toolbox™. The possibilities of potential future application of the database in statistical analysis and automation of experiments on speech inversion using DBN are described in the paper as well. Image, graphical abstract [ABSTRACT FROM AUTHOR]

The aim of this study is to quantify potential systemic timing bias between fully automatic timing (FAT) and timing with iPhone camera (Apple Inc., Cupertino, CA, USA) and then consider whether an iPhone can be used as an inexpensive timing system for sprint events at athletics competitions. A flashlight was aimed at FAT camera (Lynx System Developers, Haverhill, MA, USA) and two iPhones, at 120 and 240 frames per second (fps), respectively, so that they could capture the light from it. By turning the flashlight on and off at varying intervals (1–33 s, average 9.5 s), the cameras captured a series of light beams. The time intervals between the start of two light beams were measured 31 times on the recordings from all the cameras. On each recording with the iPhones, two analyses were performed: one where the video image before the light beam (start before light) from the flashlight was set to 0 s and one where the first image with the light beam (start on light) was set to 0 s. Start on light showed no significant time differences compared to FAT. With 240 fps the standard deviation was ± 0.001 s, 29% of the times were the same as FAT, while 81% of the times are within ± 0.001 s. The largest deviation was a time of −0.003 s from FAT. With 120 fps there was a standard deviation of ± 0.003 and a maximum deviation of −0.006 s, where 39% of the times were within ± 0.001 s. At start before light, a significant but expected difference was found with an average deviation of +0.008 s with 120 fps and +0.004 s with 240 fps, with maximum deviations of +0.014 and +0.006 s. It can be concluded that the camera on an iPhone is accurate as we did not find any systematic bias from FAT with start on light.

The current study presents the effects of seasonal variations in the depth-of-closure (D c) on shoreline evolution using a numerical, one-line shoreline model. Beach erosion of the southern beach of the Nha Trang Coast, which is located in south central of Vietnam, is selected as the study area. This study area is immensely influenced by the tropical monsoon climate that has a clear pattern of large waves in the northeast monsoon season and calm waves in the non-monsoon season. The analysis of the long-term measured shoreline variations from a video-camera system has found a strong correlation of these variations to the monsoon-dominated wave characteristics in the Nha Trang Bay. Therefore, a new approach for determining the depth-of-closure with consideration of the seasonal wave climate changes is purposed in the current study. By implementing this new approach into a numerical, one-line shoreline model, it is found that the seasonal variations of D c appear to better describe the periodical shoreline evolution due to the monsoon-dominated wave characteristics for the Nha Trang Coast. Such important findings are considered to commonly apply for monsoon-dominated coastal regions in general. These findings are useful information not only for scientific readers but also for the coastal authorities and managers in order to make better countermeasure plans against this kind of erosion mechanism in the future. [ABSTRACT FROM AUTHOR]

The paper briefly overviews the development of unmanned surface ship technology over the last 20 years. Main problems of their navigation equipment and algorithms, and their compliance with the International Maritime Organization requirements are discussed. [ABSTRACT FROM AUTHOR]

The Level of Service (LOS) for a priority junction is identified by the delay calculated for each movement. Because of the complexity of the traffic operations, various methods have been studied to evaluate more precise delay. This paper reviews benchmarks of these methods developed over past 55 years from Tanner's method, 1962, until now. The precision of these techniques is examined using real data from two priority junctions, i.e. three-legged formed, with multilane on the major and minor road. About 9-h data were gathered for each junction from morning until evening using video camera technique. This, in total, provided 18 hdata recording on normal working days. Then, observed delays incurred on minor road vehicles are compared with approximated delays from reviewed techniques. The study found that Brilon's and Troutbeck's methods that are the most popular methods provide consistent and closest calculated delay at priority junction. Additionally, Highway Capacity Manual (HCM) is an appropriate method only during low saturation where volume over capacity is less than 0.9. [ABSTRACT FROM AUTHOR]

There is a close relationship between the visual technologic tools like video camera and photo camera, however this relationship is not considered generally. Knowing that there are various ideologies in the background of technological tools that enable visualization will bring about a more rational approach to these technologies. While image technology devices are being produced, the system determines its ideological approach; produced technologies are manufactured within the framework of these ideologies; that is, before these technologies are produced, it is considered important to limit the visual field and to reduce thinking practices. The depth of field feature of video cameras is very important in terms of reflecting the relationship between technology and ideology. It is accepted that the first stage of people's reasoning, thinking, imagination and awareness is seeing and in this sense, seeing is given special value. While the keeping visual field wide allows more awareness, the restriction of the visual field leads to unconsciousness or awareness as desired by the system. The majority of people using a video camera shoot in the Auto option, where control is left to the camera. When shooting with camcorders in the Auto option, the field of view is limited, that is, the depth of field is reduced; thinking practices occur in the way the system wants. This is targeted in the production process of video cameras on purpose. However, when the video is taken in the Manual option, the visual field can be expanded by the user and this allows people to think. This study aims to show the relationship between video camera and ideology in the context of depth of field. In addition to this aim, the study intends to explain that these devices could be an alternative ideology by exactly knowing the features of the video cameras used . [ABSTRACT FROM AUTHOR]

Copyright of Technical Diagnostics & Nondestructive Testing / Tekhnicheskaya Diagnostika I Nerazrushayushchiy Kontrol is the property of International Association Welding (Paton Publishing House) and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)