Viewing Angle Research Articles

Развитие методологии управления риском на взрывопожароопасных объектах предприятий

The article formulates a new concept for the integrated safety, clarifies the concept for the integrated safety system of explosive production facilities of the enterprises. Aggregated areas with scientific results on risk assessment in the integrated safety of production enterprises was formed. To improve safety at the enterprises under consideration, it was required to solve three problems. To solve the first problem, the current, practical results of the scientific research were analyzed both in Russia and in the foreign countries. It is concluded that the reduction of damage from the impact of hazardous events is to create a reasonable reserve designed to reduce (exclude) various risks, the rational use of the reserve based on the use of an approach developed from a new angle of view in relation to risk. When solving the second problem, the existing methods for assessing the state of the industrial and fire safety subsystems, occupational safety included in the integrated safety system of the enterprises under consideration, as well as a new direction for assessing the state of the integrated safety were presented in comparison. When solving the third problem, a formalized description of a new, different from the used model for improving and developing the integrated safety system for explosive production facilities of the enterprises is presented. The purpose of the assessment is formulated, the new methods and results of the assessment of the state of the integrated safety of these enterprises are presented. As a result, three problems were solved, on their basis the conceptual model for the development of the integrated safety system for explosive production facilities of the enterprises was formed.

Large-field Gesture Tracking and Recognition for Augmented Reality Interaction

In recent years, with the continuous development of computer vision and artificial intelligence technology, gesture recognition is widely used in many fields, such as virtual reality, augmented reality and so on. However, the traditional binocular camera architecture is limited by its limited field of view Angle and depth perception range. Fisheye camera is gradually applied in gesture recognition field because of its advantage of larger field of view Angle. Fisheye cameras offer a wider field of vision than previous binocular cameras, allowing for a greater range of gesture recognition. This gives fisheye cameras a distinct advantage in situations that require a wide field of view. However, because the imaging mode of fisheye camera is different from traditional camera, the image of fisheye camera has a certain degree of distortion, which makes the calculation of gesture recognition more complicated. Our goal is to design a distortion correction processing strategy suitable for fisheye cameras in order to extend the range of gesture recognition and achieve large field of view gesture recognition. Combined with binocular technology, we can use the acquired hand depth information to enrich the means of interaction. By taking advantage of the large viewing Angle of the fisheye camera to expand the range of gesture recognition, make it more extensive and accurate. This will help improve the real-time and precision of gesture recognition, which has important implications for artificial intelligence, virtual reality and augmented reality.

Illuminance Analysis according to View Angle Changes of Large-area Flat-type LED Lighting System to Improve Optical Characteristics

Illuminance Analysis according to View Angle Changes of Large-area Flat-type LED Lighting System to Improve Optical Characteristics

Spin-polarization control of in-plane scattering in arrays of asymmetric U-shaped nanoantennas.

We study projection-enabled enhancement of asymmetric optical responses of plasmonic metasurfaces for photon-spin control of their far field scattering. Such a process occurs by detecting the light scattered by arrays of asymmetric U-shaped nanoantennas along their planes (in-plane scattering). The nanoantennas are considered to have relatively long bases and two unequal arms. Therefore, as their view angles along the planes of the arrays are changed, they offer an extensive range of shape and size projections, providing a wide control over the contributions of plasmonic near fields and multipolar resonances to the far field scattering of the arrays. We show that this increases the degree of the asymmetric spin-polarization responses of the arrays to circularly polarized light, offering a large amount of chirality. In particular, our results show the in-plane scattering of such metasurfaces can support opposite handedness, offering the possibility of photon spin-dependent directional control of energy routing.

Development of IoT-Based Real-Time Fire Detection System Using Raspberry Pi and Fisheye Camera

In this study, an IoT-based fire detection system was developed to detect and prevent damage from forest fires at an early stage. In Korea, forest fires spread quickly due to the dry climate and winds in spring and autumn, so quick detection and prevention is necessary. To quickly detect and prevent forest fires that occur periodically, a real-time fire detection system was developed by combining a Raspberry Pi and a fisheye camera. A lens with a 220° angle of view was installed, and an image analysis algorithm was implemented using the OpenCV library. The location of the fire was estimated by calculating the polar coordinates of the omnidirectional images. Using the Wi-Fi communication function of the Raspberry Pi, the acquired continuous images were transmitted to the Firebase database, and the images were analyzed to identify the movement path of the forest fire. The developed system was applied to a mountainous area near the Samcheok Campus of Kangwon National University. As a result of the experiment, when the location of points about 25.9 m (average) away from the observation point was predicted, the positional error was analyzed to be about 1.1 m. If the system is improved in the future, it is expected that it will be able to contribute to the early prevention of forest fires with fast and accurate responses.

Reconfigurable coaxial single-photon LIDAR based on the SPAD array.

The single-photon avalanche diode (SPAD) array with time-to-digital converter (TDC) circuits on each pixel is an excellent candidate detector for imaging LIDAR systems. However, the low fill-factor of the SPAD array does not allow for efficient use of laser energy when directly adopted in a LIDAR system. Here, we design a reconfigurable coaxial single-photon LIDAR based on the SPAD array and diffractive optical elements (DOEs). We use the DOE and beam expander to shape the laser beam into a laser dot matrix. The total divergence angle of the DOE spot beam is strictly matched to the total field of view (FOV) angle of the SPAD array. Meanwhile, each focused beamlet is individually matched to every active area of the SPAD array detector, which increases the use of output energy about 100 times compared to the diffusion illumination system. Besides, the system uses the active area as the minimum pixel and can support sub-pixel scanning, resulting in higher resolution images. Through this coaxial structure, two different telescope systems after transceiver switching can be reconfigured for imaging targets at different distances. Based on our single-photon LIDAR system, we achieved 3D imaging of targets at 100m and 180m using two different telescope configurations.

Approximate Evaluation of the Resolution in Near Field Remote Sensing

In linear inverse scattering, the performance of the imaging system is sometimes evaluated in terms of its resolution, i.e., its capability to reconstruct a point-like scatterer. However, there is still a lack of analytical studies on the achievable resolution. To address this, we consider the point spread function (PSF) evaluation of the scattered near field for the single frequency and multi-view/multi-static case in homogeneous medium. Instead of numerically computing the PSF, we propose and discuss an approximate closed form under series expansions according to the angular ranges of both source and receiver location. In order to assess the effectiveness of the proposed approximation, we consider two cases including both full and limited view angles for the incident field and observation ranges. In addition, we provide a localization application to show the usefulness of the theoretical discussion. Numerical results confirmed the analytical investigations.

Near-Space Wide-Area and High-Resolution Imaging System Design and Implementation.

The near-space atmosphere is thin, and the atmospheric refraction and scattering on optical observation is very small, making it very suitable for wide-area and high-resolution surveillance using high-altitude balloon platforms. This paper adopts a 9344 × 7000 CMOS sensor to obtain high-resolution images, generating large-field-of-view imaging through the swing scanning of the photoelectric sphere and image stitching. In addition, a zoom lens is designed to achieve flexible applications for different scenarios, such as large-field-of-view and high-resolution imaging. The optical design results show that the camera system has good imaging quality within the focal length range of 320 mm-106.7 mm, and the relative distortion values at different focal lengths are less than 2%. The flight results indicate that the system can achieve seamless image stitching at a resolution of 0.2 m@20 km and the imaging field of view angle exceeds 33°. This system will perform other near-space flight experiments to verify its ultra-wide (field of view exceeding 100°) high-resolution imaging application.

The SOLAR-HRS New High-Resolution Solar Spectra for Disk-Integrated, Disk-Center, and Intermediate Cases

The solar spectrum at the top of the atmosphere contains crucial data for solar physics, astronomy, and geophysics. Accurately determining high-resolution solar reference spectra, whether they are disk-integrated, disk-center, or intermediate cases, represents a new challenge and is of primary importance for all applications where spectral solar radiation needs to be evaluated. These spectra are also essential for interpreting remote sensing measurements that rely on sunlight, such as those obtained by Earth observation satellites or spacecraft exploring other planets. This paper lays a foundation for the implementation of multiple new solar irradiance reference spectra that have high resolution and are representative of solar minimum conditions. We developed the SOLAR high-resolution extraterrestrial reference spectra (SOLAR-HRS disk-integrated spectra) by normalizing high-spectral-resolution solar line data to the absolute irradiance scale of the SOLAR-ISS reference spectrum. The resulting one-of-a-kind SOLAR-HRS disk-integrated spectrum has a spectral resolution varying between 0.001 and 1 nm in the 0.5–4400 nm wavelength range. We also implemented a new high-resolution solar spectrum at the disk-center, covering a range of 650–4400 nm with a spectral resolution of 0.001 to 0.02 nm. We further expanded our analysis by producing several solar spectra for ten different solar view angles ranging from μ = 0.9 to μ = 0.05 (SOLAR-HRS intermediate cases). Finally, we developed new Merged Parallelised Simplified ATLAS spectra (MPS-ATLAS) based on solar modeling with Kurucz and Vald3 solar linelists for both the disk-integrated and disk-center spectra. One of the objectives of implementing all these new solar spectra is to fulfill the requirements of the MicroCarb space mission, which focuses on measuring greenhouse gas emissions. The solar data of this study are openly available.

Obese patients' dissatisfaction with weight, body image and clinicians' interaction at a district hospital; Gauteng.

Obesity in South Africa has created a public health crisis that warrants a multilevel intervention. However, patients' perceptions and clinicians' challenges hinder the management of obesity in primary care. The study aimed to assess obese patients' dissatisfaction with weight and body image and their perspectives on interaction with clinicians regarding obesity management in a primary care setting. Outpatient department of Dr Yusuf Dadoo District Hospital. Cross-sectional study of 213 adult obese patients. A semi-structured questionnaire, a body image assessment tool and patients' medical records were used for data collection. The study found that, contrary to popular belief, obese patients were dissatisfied with their weight (78.9%) and body image (95.3%). Many felt comfortable while discussing weight reduction with clinicians, although 37.1% reported never engaging with a doctor and 62.9% never interacted with a nurse on the subject. Only 6% reported receiving adequate information on weight reduction measures and 19.7% were followed-up. Clinicians' advice was mainly associated with patients' high body mass index and waist circumference. Doctors were less likely to recommend weight reduction to employed obese women, while nurses were more likely to engage Zulu-speaking patients. Patients were more likely to be followed up if they were young and excessively obese. The study found that most obese patients were dissatisfied with their weight and body image and perceived their interaction with clinicians regarding obesity management as inadequate.Contribution: The study provides an angle of view of challenges in obesity management from patients' perspectives.

Molecular composition of dissolved organic matter across diverse ecosystems: Preliminary implications for biogeochemical cycling

Fourier-transform ion cyclotron resonance mass spectrometry (FT-ICR MS) has been widely applied to characterize the molecular composition of dissolved organic matter (DOM) in different ecosystems. Most previous studies have explored the molecular composition of DOM focused on one or a few ecosystems, which prevents us from tracing the molecular composition of DOM from different sources and further exploring its biogeochemical cycling across ecosystems. In this study, a total of 67 DOM samples, including soil, lake, river, ocean, and groundwater, were analyzed by negative-ion electrospray ionization FT-ICR MS. Results show that molecular composition of DOM varies dramatically among diverse ecosystems. Specifically, the forest soil DOM exhibited the strongest terrestrial signature of molecules, while the seawater DOM showed the most abundant of biologically recalcitrant components, for example, the carboxyl-rich alicyclic molecules were abundant in the deep-sea waters. Terrigenous organic matter is gradually degraded during its transport along the river-estuary-ocean continuum. The saline lake DOM showed similar DOM characteristics with marine DOM, and sequestrated abundant recalcitrant DOM. By comparing these DOM extracts, we found that human activities likely lead to an increase in the content of S and N-containing heteroatoms in DOM, this phenomenon was commonly found in the paddy soil, polluted river, eutrophic lake, and acid mine drainage DOM samples. Overall, this study compared molecular composition of DOM extracted from various ecosystems, providing a preliminary comparison on the DOM fingerprint and an angle of view into biogeochemical cycling across different ecosystems. We thus advocate for the development of a comprehensive molecular fingerprint database of DOM using FT-ICR MS across a wider range of ecosystems. This will enable us to better understand the generalizability of the distinct features among ecosystems.

Stability of slope corners: a displacement-based FEM study

The stability of slopes is typically evaluated by two-dimensional plane strain analysis. However, many slopes exhibit three-dimensional (3D) geometries, including slope corners. Several researchers have studied the stability of slope corners but found that the factor of safety (FS) was close to the FS for the plane strain case. The results of a new series of 3D finite element method (FEM) simulating slope corners, including slope angle, plan view angle, radius of curvature, and slope height are presented. They confirm that the FS does not vary much for corners compared to the plane strain case. However, 220 cases using an elastic-perfectly plastic soil model together with the FEM shear strength reduction method show that the displacement field is very different at the corners compared to plane strain with differences reaching over 100%. The displacement ratio between corners and plane strain is presented as a function of the plan view angle of the corner. Often failure is defined at a chosen large displacement, as in the ultimate load of foundation elements. If this concept is carried over to slope stability, it would indicate that the FS of corners should be very different from the plane strain case. A possible explanation is discussed.

Attention-Guided Instance Segmentation for Group-Raised Pigs.

In the pig farming environment, complex factors such as pig adhesion, occlusion, and changes in body posture pose significant challenges for segmenting multiple target pigs. To address these challenges, this study collected video data using a horizontal angle of view and a non-fixed lens. Specifically, a total of 45 pigs aged 20-105 days in 8 pens were selected as research subjects, resulting in 1917 labeled images. These images were divided into 959 for training, 192 for validation, and 766 for testing. The grouped attention module was employed in the feature pyramid network to fuse the feature maps from deep and shallow layers. The grouped attention module consists of a channel attention branch and a spatial attention branch. The channel attention branch effectively models dependencies between channels to enhance feature mapping between related channels and improve semantic feature representation. The spatial attention branch establishes pixel-level dependencies by applying the response values of all pixels in a single-channel feature map to the target pixel. It further guides the original feature map to filter spatial location information and generate context-related outputs. The grouped attention, along with data augmentation strategies, was incorporated into the Mask R-CNN and Cascade Mask R-CNN task networks to explore their impact on pig segmentation. The experiments showed that introducing data augmentation strategies improved the segmentation performance of the model to a certain extent. Taking Mask-RCNN as an example, under the same experimental conditions, the introduction of data augmentation strategies resulted in improvements of 1.5%, 0.7%, 0.4%, and 0.5% in metrics AP50, AP75, APL, and AP, respectively. Furthermore, our grouped attention module achieved the best performance. For example, compared to the existing attention module CBAM, taking Mask R-CNN as an example, in terms of the metric AP50, AP75, APL, and AP, the grouped attention outperformed 1.0%, 0.3%, 1.1%, and 1.2%, respectively. We further studied the impact of the number of groups in the grouped attention on the final segmentation results. Additionally, visualizations of predictions on third-party data collected using a top-down data acquisition method, which was not involved in the model training, demonstrated that the proposed model in this paper still achieved good segmentation results, proving the transferability and robustness of the grouped attention. Through comprehensive analysis, we found that grouped attention is beneficial for achieving high-precision segmentation of individual pigs in different scenes, ages, and time periods. The research results can provide references for subsequent applications such as pig identification and behavior analysis in mobile settings.

The geopolitical area of televised debate in crisis/emergency conditions: Unghiuri de vedere program, Moldova 1

Through its actions of informing, explaining and treating the events of our daily lives, the mass media long ago became, rightly, the barometer of society. But, as the author of the article mentions, the optics of the reflection and interpretation of reality by the mass media changes substantially in the conditions of the crisis and the state of emergency, such as those currently imposed on the Republic of Moldova, as well as on other countries, by the war unleashed by Russia against Ukraine. Against the background of the events taking place at the borders of our country, the approach to reality by the national media and not only, makes a substantial leap from political to geopolitical. In this way, the media coverage of facts and events is increasingly subject to disinformation, through fake news and propaganda, carried out in our country by part of the mass media in the country and abroad, by certain politicians, representatives of the opposition parties, and by some internet bloggers. In this context, the task of our bona fide mass media is not only to inform the public correctly, but also to fight misinformation and manipulation of public opinion. Concretely, the article examines the tasks that fall in this regard to the new specialized program Angles of View, proposed by the Public TV Station Moldova 1. In this regard, the author makes rigorous conclusions and proposals to counteract propaganda and manipulation of public opinion in the conditions of the crisis and the state of emergency imposed on our country by regional geopolitics.

Using of Conspicuous of Body Angularities Type Traits to Milk Yields as Dairy Cattle Selection Preferences

Numerous papers have been published on body cattle angularities subject in a few backward decades. However, the preeminent body angularities to the milk yield are unstipulated assertively. Hence, the current odyssey was to determine the transcendence body angular of dairy cattle interrelated with the milk yield for selection preferences. In total, 121 head of Holstein cows and seven reputable cattle body angularities were engaged as samples and measured variables for investigation. The software R version 4.2.1 and RStudio was operated simultaneously to facilitate statistical analysis. Later, the principal components (PCA), correlation, and regression analysis were carried out in that order. The PCA specified the thurl angle (TLA), hock side view angle (HSA), hock back views angle (HBA), and fore udder angle (FUA) as crucial factors of body cattle angularities. Then, the correlation analysis appointed HBA and TLA in series as the best trait related to milk yields. The regression analysis was merely entrusted to the HBA as a factor for prognosticating milk yield potency. Thus, the upshot of the ongoing exploration prompted the HBA as the main priority for milk yield selection preferences, followed by TLA. Both were usable on the calf, heifer, and cow selection scheme but should be enforced regularly.

Row orientation influences the diurnal cycle of solar-induced chlorophyll fluorescence emission from wheat canopy, as demonstrated by radiative transfer modeling

Although multiple studies have used solar-induced chlorophyll fluorescence (SIF) of the crop canopy to estimate photosynthetic activity, the effect of canopy geometry (row orientation) on diurnal SIF remains uncertain. Using a combination of 3D canopy radiative transfer modeling and spectroscopic observations collected in a winter wheat field, we investigated (i) the relationships between observed SIF and factors including temperature, humidity, absorbed photosynthetically active radiation (APAR), and row orientation; (ii) the temporal pattern and multi-angle distribution of diurnal canopy SIF; and (iii) the mechanisms influencing components of diurnal SIF under the effect of row orientation. The relationship between observed SIF and APAR was relatively strong at the early growth period, but SIF was influenced by various factors (temperature, humidity, and row–sun angle) at the middle of the growth period. To test an asymmetric crop row effect as a potential cause of this skewness, we evaluated the modeled SIF with a 3D northwestward (315°) crop row alignment and other orientations. Each row orientation resulted in a trough-like depression parallel to the row in simulated canopy SIF, which could cause a diurnal asymmetry of canopy SIF, a fraction of fluorescence escape, and a fraction of APAR. View angles, the dimension of canopy objects (1D/3D), inter-row width, and leaf structure parameters impacted the representativeness of these simulations. An increased shade SIF, synchronized with the time when row–sun angles become zero at the incident sunlight being parallel to the crop row, was linked to decreasing canopy SIF emissions and would cause a non-linear SIF–APAR relationship at certain row orientations especially facing diagonally to the south. The concept of row orientation provides a novel viewpoint of diurnal canopy SIF from which to test the effect of row geometry in cropland, and will promote a mechanistic understanding of photosynthesis and canopy light use.

Stabilization of Two Axis Gimbal System with Self Tuning PID Control

Gimbal is a system that provides locking and tracking of the seeker on the target in missiles and increases the angle of view with its mobility in two axes. In this study, stabilization of a two-axis gimbal system used in the missile was carried out. In gimbal stabilization, adaptive controllers are preferred instead of classical controllers due to unbalance, cross-coupling, and unmeasurable disturbances. A Self Tuning PID controller based on Fuzzy Logic was developed for axis controls in the stabilization algorithm. Thanks to this controller, which works with the principle of choosing the most appropriate coefficient at every step, it was possible to control with less than 3% errors in the tests performed with the flight simulator. In addition, a PID controller whose coefficients are optimized with Particle Swarm Optimization is designed for comparison purposes. In experimental studies, it was seen that PID with adjustable coefficients gave better results than the fixed PID.

Multispectral Invisible Coating: Laminated Visible-Thermal Physical Attack against Multispectral Object Detectors Using Transparent Low-E Films

Multispectral object detection plays a vital role in safety-critical vision systems that require an around-the-clock operation and encounter dynamic real-world situations(e.g., self-driving cars and autonomous surveillance systems). Despite its crucial competence in safety-related applications, its security against physical attacks is severely understudied. We investigate the vulnerability of multispectral detectors against physical attacks by proposing a new physical method: Multispectral Invisible Coating. Utilizing transparent Low-e films, we realize a laminated visible-thermal physical attack by attaching Low-e films over a visible attack printing. Moreover, we apply our physical method to manufacture a Multispectral Invisible Suit that hides persons from the multiple view angles of Multispectral detectors. To simulate our attack under various surveillance scenes, we constructed a large-scale multispectral pedestrian dataset which we will release in public. Extensive experiments show that our proposed method effectively attacks the state-of-the-art multispectral detector both in the digital space and the physical world.

Insight into the plant-associated bacterial interactions: Role for plant arsenic extraction and carbon fixation

This study investigated the interactions between rhizosphere and endosphere bacteria during phytoextraction and how the interactions affect arsenic (As) extraction and carbon (C) fixation of plants. Pot experiments, high-throughput sequencing, metabonomics, and network analysis were integrated. Results showed that positive correlations dominated the interconnections within modules (>95 %), among modules (100 %), and among keystone taxa (>72 %) in the bacterial networks of plant rhizosphere, root endosphere, and shoot endosphere. This confirmed that cooperative interactions occurred between bacteria in the rhizosphere and endosphere during phytoextraction. Modules and keystone taxa positively correlating with plant As extraction and C fixation were identified, indicating that modules and keystone taxa promoted plant As extraction and C fixation simultaneously. This is mainly because modules and keystone taxa in plant rhizosphere, root endosphere, and shoot endosphere carried arsenate reduction and C fixation genes. Meanwhile, they up-regulated the significant metabolites related to plant As tolerance. Additionally, shoot C fixation increased peroxidase activity and biomass thereby facilitating plant As extraction was confirmed. This study revealed the mechanisms of plant-associated bacterial interactions contributing to plant As extraction and C fixation. More importantly, this study provided a new angle of view that phytoextraction can be applied to achieve multiple environmental goals, such as simultaneous soil remediation and C neutrality.

A Vision-Based Autonomous Landing Guidance Strategy for a Micro-UAV by the Modified Camera View

Autonomous landing is one of the key technologies for unmanned aerial vehicles (UAVs) which can improve task flexibility in various fields. In this paper, a vision-based autonomous landing strategy is proposed for a quadrotor micro-UAV based on a novel camera view angle conversion method, fast landing marker detection, and an autonomous guidance approach. The front-view camera of the micro-UAV video is first modified by a new strategy to obtain a top-down view. By this means, the landing marker can be captured by the onboard camera of the micro-UAV and is then detected by the YOLOv5 algorithm in real time. The central coordinate of the landing marker is estimated and used to generate the guidance commands for the flight controller. After that, the guidance commands are sent by the ground station to perform the landing task of the UAV. Finally, the flight experiments using DJI Tello UAV are conducted outdoors and indoors, respectively. The original UAV platform is modified using the proposed camera view angle-changing strategy so that the top-down view can be achieved for performing the landing mission. The experimental results show that the proposed landing marker detection algorithm and landing guidance strategy can complete the autonomous landing task of the micro-UAV efficiently.