Correlation of retinal alterations with vascular structure of macular neovascularisation in swept-source optical coherence tomography angiography in age-related macular degeneration

Purpose The aim of this study was to find out whether the vascular architecture of untreated macular neovascularisations (MNV) in neovascular age-related macular degeneration (nAMD) as visualised with optic coherence tomography angiography (OCTA) is associated with functional and known morphological alterations of the retina in optic coherence tomography (SD-OCT). Methods The study design was retrospective with consecutive patient inclusion. In 107 patients with newly diagnosed nAMD, MNV were detected by means of OCTA and automated quantitative vascular analysis was performed. The MNV characteristics measured were area, flow density, total vascular length (sumL), density of vascular nodes (numN), fractal dimension (FD) and average vascular width (avgW). These parameters were assessed for associations with vision (BCVA), central retinal thickness (CRT), fluid distribution, the elevation of any pigment epithelial detachment (PED), the occurrence of subretinal haemorrhage and atrophy. Results BCVA was significantly worse with greater MNV area and sumL. Fluid distribution differed significantly in relation to area (p < 0.005), sumL (p < 0.005) and FD (p = 0.001). Greater PED height was significantly associated with higher numN (p < 0.05) and lower avgW (p < 0.05). Atrophy was present significantly more often in MNV with larger area (p < 0.05), higher sumL (p < 0.05) and higher flow density (p = 0.002). None of the MNV parameters had a significant association with CRT or the occurrence of haemorrhage. Conclusion OCTA is not restricted to evaluation of secondary changes but offers the opportunity to analyse the vascular structure of MNV in detail. Differences in vascular morphology are associated with certain secondary changes in retinal morphology. There are thus grounds for optimism that further research may identify and classify OCTA-based markers to permit more individualised treatment of nAMD.

Fitting Empirical Fundamental Diagrams of Road Traffic: A Comprehensive Review and Comparison of Models Using an Extensive Data Set

<div>Understanding the inter-relationships between traffic flow, density, and speed through the study of the fundamental diagram of road traffic is critical for traffic modelling and management. Consequently, over the last 85 years, a wealth of models have been developed for its functional form. However, there has been no clear answer as to which model is the most appropriate for observed (i.e. empirical) fundamental diagrams and under which conditions. A lack of data has been partly to blame. Motivated by shortcomings in previous reviews, we first present a comprehensive literature review on modelling the functional form of empirical fundamental diagrams. We then perform fits of 50 previously proposed models to a high quality sample of 10,150 empirical fundamental diagrams pertaining to 25 cities. Comparing the fits using information criteria, we find that the non-parametric Sun model greatly outperforms all of the other models. The Sun model maintains its winning position regardless of road type and congestion level. Our study, the first of its kind when considering the number of models tested and the amount of data used, finally provides a definitive answer to the question ``Which model for the functional form of an empirical fundamental diagram is currently the best?''. The word ``currently'' in this question is key, because previously proposed models adopt an inappropriate Gaussian noise model with constant variance. We advocate that future research should shift focus to exploring more sophisticated noise models. This will lead to an improved understanding of empirical fundamental diagrams and their underlying functional forms.</div><div><br></div><div>Accepted by IEEE Transactions On Intelligent Transportation Systems on 14th Dec 2021<br></div><br>

KARAKTERISTIK MARSHALL KERAMIK SEBAGAI AGREGAT HALUS DAN FILLER PADA CAMPURAN HOT ROLLER SHEET (HRS)

Penelitian ini mengenai pemanfaatan bahan sisa keramik pada pemasangan lantai rumah sebagai agregat halus dan filler dalam pembuatan lapis perkerasan aspal. Sebagai bahan agregat halus dan filler, keramik dicampur dengan Semen Portland dengan komposisi tertentu. Hal ini dilakukan untuk meningkatkan daya ikat antar butiran keramik. Penelitian ini dilakukan untuk mengetahui penggunaan keramik sebagai dan agregat halus dan filler pada campuran HRS-WC terhadap karakteristik stabilitas, flow, density, VITM, VFWA, VMA, Marshall Quotient dan Immersion Test. Tahap pertama dimulai dari pemeriksaan bahan aspal dan agregat menggunakan spesifikasi Bina Marga. Tahap kedua membuat benda uji untuk mencari kadar aspal optimum dengan filler abu batu dengan kadar aspal 4%, 4,5%, 5%, 5,5%, dan 6%. Tahap ketiga dilakukan pengujian Marshall standar dan Immersion Test pada variasi agregat halus dan filler dengan kadar yaitu 0% keramik, 25% keramik, 50% keramik, 75% keramik dan 100% keramik dengan menggunakan kadar aspal optimum. Dari hasil penelitian dapat disimpulkan bahwa semakin banyak penambahan keramik akan menurunkan nilai stabilitas, Marshall Quotient, VITM dan VMA dan menaikkan nilai flow, density dan VFWA. Keramik dapat digunakan sebagai agregat halus dan filler dalam pembuatan lapis perkerasan HRS dengan variasi kadar 25% keramik.

Analysis of the Relationship between the Density and Lane-Changing Behavior of Circular Multilane Urban Expressway in Mixed Traffic

The behavior of changing lanes has a great impact on road traffic with heavy traffic. Traffic flow density is one of the important parameters that characterize the characteristics of traffic flow, and it will also be affected by the behavior of changing lanes, especially in the case of each lane. The penetration of autonomous vehicles can effectively reduce lane-changing behavior. Studying the relationship between traffic flow density and lane-changing behavior under different autonomous vehicle penetration rates is of great significance for describing the operation mechanism of mixed traffic flow and the control of mixed traffic. In this article, we use empirical, simulation, and data-driven methods to analyze the urban expressway of autonomous vehicles with penetration rates of 10%, 20%, 30%, 40%, 50%, 60%, 70%, and 80%, respectively. A simulation experiment was carried out on the road, and data related to density, the rate of changing into the lanes, and the rate of changing out lanes were collected. The analysis of the experimental results found the following: (1) The increase in penetration of autonomous vehicles leads to a certain degree of downward trend in density, the rate of changing into the lanes, and the rate of changing out lanes. (2) Different lanes have different effects on the penetration of autonomous vehicles. In a 4-lane road, the two lanes farther from the entrance and exit are closer in appearance, while the two lanes closer to the entrance and exit are similar. (3) The relationship between density and the rate of changing into the lanes and the rate of changing out lanes shows a linear relationship with the penetration of autonomous vehicles. Although the performance of each lane is slightly different, in general, it can be carried out by a multiple regression model. The given parameter value range is relatively close under different permeability. In summary, autonomous vehicles effectively reduce the traffic density and lane-changing behavior of each lane. There is a linear relationship between traffic flow density and lane-changing behavior with the penetration of autonomous vehicles. The density-lane-changing behavior model proposed in this paper can better describe the relationship between the density of the circular multilane urban expressway and the lane-changing behavior in the case of a large traffic flow in mixed traffic.

Robot-Based Last-Mile Deliveries With Pedestrian Zones

Since delivery robots share sidewalks with pedestrians, it may be beneficial to choose paths for them that avoid zones with high pedestrian density. In this paper, we investigate a robot-based last-mile delivery problem considering path flexibility given the presence of zones with varying pedestrian level of service (LOS). Pedestrian LOS is a measure of pedestrian flow density. We model this new problem with stochastic travel times and soft customer time windows. The model includes an objective that reflects customer service quality based on early and late arrivals. The heuristic solution approach uses the minimum travel time paths from different LOS zones (path flexibility). We demonstrate that the presence of pedestrian zones leads to alternative path choices in 30% of all cases. In addition, we find that extended time windows may help increase service quality in zones with high pedestrian density by up to 40%.

Assessment of the Impact of Road Traffic on the Pollution of Urbanized Territories

Экономическое развитие всех регионов основано на доступе людей к товарам и услугам, которые обеспечиваются современной транспортной инфраструктурой. Автомобильный транспорт является основным способом транспортировки грузов и населения. В то же время положительные аспекты использования транспорта тесно связаны с такими негативными аспектами, как загрязнение окружающей среды и отрицательным влиянием на здоровье человека. На территории Республики Северная Осетия - Алания наибольший вклад в загрязнение окружающей среды вносит деятельность предприятий цветной металлургии и автотранспорта. Более 30 предприятий находится в промышленном узле г. Владикавказа, и их деятельность в той или иной мере связана с загрязнением атмосферного воздуха. Значительный вклад в загрязнение воздуха вносит автотранспорт, количество которого в г. Владикавказе, по данным Федеральной службы государственной статистики, за последние 20 лет увеличилось более чем в 2 раза. Цель исследования. Изучение основных источников загрязнения окружающей среды автомобильным транспортом, исследование взаимосвязей между уровнем загрязнения среды, интенсивностью движения и экологическим классом автомобильного транспорта. Установление показателя загрязнения окружающей среды автомобильным транспортом, характеризующего степень воздействия на окружающую среду и здоровье населения. Методы исследования. В ходе настоящей работы были собраны и проанализированы все имеющиеся данные по динамике объемов выбросов от стационарных источников и автотранспорта на территории РСО-А за 1997–2015 гг. Указанные данные обрабатывались с помощью корреляционного и регрессионного анализов. Результаты работы. Результаты исследований позволили установить, что прослеживается прямая зависимость или тренд между плотностью потока машин и загрязнением воздушной среды. Установлено, что выбросы от автомобильного транспорта на порядок превосходят стационарные источники. Предложен суммарный показатель Zатм загрязнения атмосферного воздуха, рассчитываемый как сумма отношений концентрации отдельных загрязнителей к соответствующим значениям ПДК за вычетом количества используемых показателей. The economic development of any country is based on the access of population to goods and services that are provided by modern transport infrastructure. Currently, road transport is the most common way of transporting goods and people. At the same time, the positive aspects of using transport are closely related to such negative aspects as environmental pollution and negative impact on public health. On the territory of the Republic of North Ossetia-Alania, the largest contribution to environmental pollution is made by the activities of non-ferrous metallurgy enterprises and vehicles. More than 30 enterprises are located in the industrial hub of the city of Vladikavkaz, and their activities to one degree or another are associated with atmospheric air pollution. A significant contribution to air pollution is made by motor vehicles.Their number in Vladikavkaz has more than doubled over the past 20 years, according to the Federal State Statistics Service. Aim. Study of the main sources of pollution of an urbanized area by road transport. The research and identification of the relationship between the level of environmental pollution, traffic intensity and the ecological class of road transport and the establishment of an indicator of environmental pollution by road transport, characterizing the degree of impact on the environment and safety of the population. Methods. In the course of this study, all the available data on the dynamics of emissions from stationary sources and vehicles on the territory of North Ossetia-A for 1997–2015 were collected and analyzed. These data were processed using correlation and regression analyzes. Results.The research results made it possible to establish that there is a direct relationship or trend between the flow density of cars and air pollution. It was found that emissions from road transport exceed stationary sources by an order of magnitude. A total indicator Zatm of atmospheric air pollution is proposed, calculated as the sum of the ratios of the concentration of individual pollutants to the corresponding MPC values minus the number of indicators used.

Improvement of Retinal Microcirculation after Pulmonary Vein Isolation in Patients with Atrial Fibrillation—An Optical Coherence Tomography Angiography Study

Purpose: To evaluate retinal and optic nerve head (ONH) perfusion in patients with atrial fibrillation (AF) before and after catheter ablation of AF with pulmonary vein isolation (PVI). Methods: 34 eyes of 34 patients with AF and 35 eyes of 35 healthy subjects were included in this study. Flow density data were obtained using spectral-domain OCT-A (RTVue XR Avanti with AngioVue, Optovue, Inc, Fremont, California, USA). The data of the superficial and deep vascular layers of the macula and the ONH (radial peripapillary capillary network, RPC) before and after PVI were extracted and analysed. Results: The flow density in the superficial OCT-angiogram (whole en face) and the ONH (RPC) in patients with AF was significantly lower compared to healthy controls (OCT-A superficial: study group: 48.77 (45.19; 52.12)%; control group: 53.01 (50.00; 54.25)%; p < 0.001; ONH: study group: 51.82 (48.41; 54.03)%; control group: 56.00 (54.35; 57.70)%; p < 0.001;). The flow density in the ONH (RPC) improved significantly in the study group following PVI (before: 51.82 (48.41; 54.03)%; after: 52.49 (50.34; 55.62)%; p = 0.007). Conclusions: Patients with AF showed altered ocular perfusion as measured using OCTA when compared with healthy controls. Rhythm control using PVI significantly improved ocular perfusion as measured using OCT-A. Non-contact imaging using OCTA provides novel information about the central global microperfusion of patients with AF.

Application of Extended Lattice Gas Automata Model in Ship Evacuation Simulation

Lattice gas automaton is a mathematical model that is used to simulate the horizontal uniform evacuation behaviour of a group. However, extended lattice gas automata model is proposed to examine marine evacuation behaviour, which is subject to deck heeling. The application of distance accumulation algorithm and the conversion probability mostly make the extended model, while the approach deals with the most complicated ship evacuation. Moreover, the suggested model is expected to enhance the safety and efficiency of evacuation. The distance accumulation lattice gas automata model considers multiple movement behaviours, flow density, deck heeling, counterflow, and congestion. Movement behaviour will be severely affected in deck heeling process where people may walk normally, walk while bent over, or crawl. To verify the proposed model, 11 test scenarios and several emergency evacuation scenarios are demonstrated. The simulation results explain the validity of another experimental model. The number of people in counterflow, deck heeling, and difference in movement have a direct effect on evacuation, which is as discussed in results. This research article provides a brief study on ship design and crew response behaviour in case of mishap/accident.

Angular momenta in fields from a rotational mechanical antenna

Mechanic antennas provide opportunities for human portable, VLF communications, where a rotational dipole emits EM signals with angular momenta. In this paper we analytically derive the electromagnetic fields from a rotational electric dipole using Fourier transform method, and find that the radiated fields from the rotational electric dipole carries nonzero energy flow density in both orbital and spin angular momentum (AM) parts by AM flux tensors. Intuitively, a rotation of a dipole induces a longitudinal orbital angular momentum and a longitudinal spin angular momentum both circulating in the rotation direction. And the binding force for the rotational electric dipole is then shown to result mainly from the Coulomb fields. We believe that our work can provide novel communication designs for portable mechanic antennas.

Freeway ramp metering based on PSO-PID control

Ramp metering on freeway is one of the effective methods to alleviate traffic congestion. This paper advances the field of freeway ramp metering by introducing an application to the on-ramp, capitalizing on the macro traffic follow theory and improved the freeway traffic flow. The Particle Swarm Optimization (PSO) based on Proportional Integral Derivative (PID) controller is further developed to single ramp metering as well as to optimize the PID parameters. The approach is applied to a case study of the Changyi Freeway(G5513) in Hunan, China. The simulation is conducted by applying the actual profile traffic data to PID controller to adjust the entering traffic flow on the freeway on-ramp. The results show that the PSO-PID controller tends to converge in about 80 minutes, and the density tends to be stable after 240 iterations. The system has smaller oscillation, more accurate adjustment of ramp regulation rate, and more ideal expected traffic flow density. The traffic congestion on mainline is effectively slowed down, traffic efficiency is improved, and travel time and cost are reduced. The nonlinear processing ability of PSO-PID controller overcomes the defects of the traditional manual closing ramp, and can be successfully applied in the field of intelligent ramp metering.