Stopping Point Research Articles

Multiple breath washout (MBW) testing using sulfur hexafluoride: reference values and influence of anthropometric parameters

BackgroundMultiple breath washout (MBW) using sulfur hexafluoride (SF6) has the potential to reveal ventilation heterogeneity which is frequent in patients with obstructive lung disease and associated small airway dysfunction. However,...

Anatomical Study on the Reconstruction of the Anterior Talofibular Ligament

The purpose of this study aimed to (1) identify the relationship between the fibula and the talus of the anterior talofibular ligament (ATFL); (2) collect detailed anatomical data and provide anatomical basis for ATFL anatomical reconstruction. We selected 27 ankle specimens of adult cadavers (9 left feet and 18 right feet in 11 males and 16 females; mean age 41.6 years) with the exception of ankle deformities, fractures, underdevelopment and degenerative diseases. In these 27 specimens,15 cases of ATFL were divided into two bundles and 12 cases of ATFL were single bundles. The average ATFL length was 20.31 ± 3.12mm. The center of the ATFL in 11 specimens was located in the calcaneofibular ligament (CFL) foot print area. The long axis of the fibula side stop point was 8.83±1.82 mm, and the short axis was 3.12±0.49 mm. The distance from the center of the ATFL fibula attachment area to the tip of the fibula was 14.22±2.87 mm, and the distance from the center of the CFL is 5.57±1.80mm. The distance from the center of the ATFL talar attachment area to the tibiotalar articular surface was (9.74±2.12) mm, and the distance from the anterior external cartilage surface of the talus was (4.87±1.82) mm. The angle between ATFL and the long axis of the fibula is 78°±12°. Our results suggest that in ATFL reconstruction, the anatomical attachment points around the ATFL or the angle between ATFL and the long axis of the fibula both can be used for bone canal positioning.

Optimizing a vehicle’s route in an on-demand ridesharing system in which users might walk

Within the context of a shared on-demand transport system, we study the problem of selecting the stopping points from which passengers should walk to their exact destinations (or from their exact origins). We focus on the single-vehicle case that must follow a predefined order of requests, posing the mathematical program, showing that it can be solved in polynomial time and proposing a heuristic that runs faster. We compare the optimal algorithm, the heuristic, and the routes that visit the exact request points, and we show that avoiding detours can reduce total costs by almost one fifth and vehicle costs by more than one third. The heuristic yields competitive results. Simulations over the real street network from Manhattan show that the time reduction achieved by the heuristic might be crucial to enable the system to operate in real-time.

A pilot study evaluating GSK1070806 inhibition of interleukin-18 in renal transplant delayed graft function

IntroductionDelayed graft function (DGF) following renal transplantation is a manifestation of acute kidney injury (AKI) leading to poor long-term outcome. Current treatments have limited effectiveness in preventing DGF. Interleukin-18 (IL18), a biomarker of AKI, induces interferon-γ expression and immune activation. GSK1070806, an anti-IL18 monoclonal antibody, neutralizes activated (mature) IL18 released from damaged cells following inflammasome activation. This phase IIa, single-arm trial assessed the effect of a single dose of GSK1070806 on DGF occurrence post donation after circulatory death (DCD) kidney transplantation.MethodsThe 3 mg/kg intravenous dose was selected based on prior studies and physiologically based pharmacokinetic (PBPK) modeling, indicating the high likelihood of a rapid and high level of IL18 target engagement when administered prior to kidney allograft reperfusion. Utilization of a Bayesian sequential design with a background standard-of-care DGF rate of 50% based on literature, and confirmed via extensive registry data analyses, enabled a statistical efficacy assessment with a minimal sample size. The primary endpoint was DGF frequency, defined as dialysis requirement ≤7 days post transplantation (except for hyperkalemia). Secondary endpoints included safety, pharmacokinetics and pharmacodynamic biomarkers.ResultsGSK1070806 administration was associated with IL18-GSK1070806 complex detection and increased total serum IL18 levels due to IL18 half-life prolongation induced by GSK1070806 binding. Interferon-γ−induced chemokine levels declined or remained unchanged in most patients. Although the study was concluded prior to the Bayesian-defined stopping point, 4/7 enrolled patients (57%) had DGF, exceeding the 50% standard-of-care rate, and an additional two patients, although not reaching the protocol-defined DGF definition, demonstrated poor graft function. Six of seven patients experienced serious adverse events (SAEs), including two treatment-related SAEs.ConclusionOverall, using a Bayesian design and extensive PBPK dose modeling with only a small sample size, it was deemed unlikely that GSK1070806 would be efficacious in preventing DGF in the enrolled DCD transplant population.Trial registrationNCT02723786.

Inertial Measurement Unit-Based Optimization Control of a Soft Exosuit for Hip Extension and Flexion Assistance

Abstract The optimization of the assistive force of a soft exosuit is crucial to the assistive effect. In this paper, an inertial measurement unit (IMU)-based optimization controller was designed to provide effective hip extension and flexion assistance for a soft hip-assistive exosuit. The parameters of the assistive profiles that were defined by two functions were approximatively estimated based on an analysis of biological hip power, and then optimized in real time using the hip angles measured by two IMUs bound to the thighs of the wearer. The peak and offset timings were determined using the parameters of the previous gait, while the start and stop points were determined from those of the current gait. Confirmation experiment was conducted in which four subjects were tested to demonstrate the validity of the optimization by applying the optimized parameters to the soft exosuit developed by the authors' group. Two of the subjects completed the outdoor walking test at a self-determined pace while carrying a load of 15 kg. All the subjects conducted the walking test on a treadmill at a constant speed of 1.53 m/s with the same load. The results showed that the proposed optimization controller worked well without considering individual differences. In the outdoor walking test, the wearer's natural gait could be maintained by applying the optimized assistive forces. In the treadmill walking test, metabolic rate with assistance turned on was reduced by 8.53 ± 2.65% (average ± SEM) compared with the result of assistance turned off.

Using «Kansky indices» to Estimate Transport and Geographical Simplexes

In the article, using the «γ» index as an example, we propose a way to use a number of «Kansky’s indices» to estimate transport-geographical simplexes. As a rule, «Kansky Indices» are used for comparative assessment of spatial and / or temporal differences in the transport network as a whole. However, in the system of mass public transport, subject to direct passenger traffic, through the projection of general properties formed by a combination of graphs of different routes, a «woven» graph onto its individual elements - vertices, these indices can serve to characterize certain stopping points and adjacent to them territories. They will demonstrate the level of stability of the transport network, of which the stopping point is a part, to possible traffic disruption in some of its sections, and, accordingly, will act as one of the indicators that characterize the degree of convenience for passengers of a particular stopping point.

Particle integrator for particle-in-cell simulations of ultra-high intensity laser-plasma interactions

Particle-in-cell codes are the most widely used simulation tools for kinetic studies of ultra-intense laser-plasma interactions. Using the motion of a single electron in a plane electromagnetic wave as a benchmark problem, we show surprising deterioration of the numerical accuracy of the PIC algorithm with increasing normalized wave amplitude for typical time-step and grid sizes. Two significant sources of errors are identified: strong acceleration near stopping points and the temporal field interpolation. We propose adaptive electron sub-cycling coupled with a third order temporal interpolation of the magnetic field and electric field as an efficient remedy that dramatically improves the accuracy of the particle integrator.

Regulation of the stop points throughput capacity in urban public transport

The article considers the problem of determining the throughput capacity of bus lines, which is usually determined by the limited throughput capacity of stopping points. Currently, the throughput capacity of a stop point is usually defined as the inverse mathematical expectation of the average service time for one transportation vehicle. To account such factors as random disturbances in the transport process, appropriate correction coefficients are applied. However, it has not been proved that the considered coefficients provide acceptable results for practice in all cases. In this article, in order to study the throughput capacity, the work of a stopping point is described as a multi-channel single-phase queuing system (QS). An algorithm is proposed for simulating a public transport stopping point model based on the principle of consecutive submitting requests. The recommendations formulated for the throughput capacity regulation of stop points are illustrated by using an example of a specific stop point.

РАСЧЕТ И ВЫБОР КОНСТРУКЦИИ ПРОМЫШЛЕННОГО РЕАКТОРА ДЛЯ СИНТЕЗА ПИРРОЛОВ

Industry of pyrroles synthesis on the basis of acetylene, ammonia and amines over polyfunctional catalyst can be organised only when for its recovery the rational industrial technology allowing to synthesize this product in necessary quantity and demanded quality cheap enough from accessible raw materials is developed. Considering the issues related to the development of a new reactor with high productivity and economic efficiency, the processes running in the reactor were studied. Phase characteristics have been investigated in response to changes in acetylene conversion rate due to the height of the catalyst layer. As a result, high productivity of acetylene production with zinc-chromaluminum catalyst at the temperature range of 340-440оС is achieved for 92% when the layer height is 1200 mm from the reactor top point. Based on the mass balance as well as the experimental result, a reactor for the industrial synthesis of pyrroles has been proposed.

Analysis of Car Body and Wheel Geometry Depending on Mileage on the Wear of Tyres in Passenger Cars

This paper analyses changes in body geometry and related wheel geometry which may affect the wear of passenger car tyres. By means of an electronic device, changes were measured in the position of the spots that best reflect the changes of the body geometry. This included the front bench attachment, front suspension and rear suspension, at the beginning of the front stringers, at the end of the rear stringers, around the bulkhead, as well as the top mounting points of the McPherson struts. Changes were also identified in geometrical values for the suspension and steering system. The analysed parameters of wheel geometry included, among others, toe-in, inclination angles for all the wheels, camber and castors for front wheels, etc. Tire wear was characterized by the tyre tread size in the inner, middle and outer parts of all four vehicle wheels. Based on the results obtained, quantitative relationships were identified between the mileage of the vehicle, changes in the body geometry, changes in the suspension and steering system geometry, tyre wear and the coefficient of non-uniformity in tyre wear. It was concluded that changes in car body geometry were strictly correlated with vehicle mileage. These changes, in turn, directly influenced changes in wheel geometry which, apart from influencing vehicle safety, also contribute to excessive tyre wear.

Influence of driver behavior in the emergence of traffic gridlocks

We present a microscopic driving algorithm that prescribes the acceleration using three parameters: the distance to the leading vehicle, to the next traffic light and to the nearest stopping point when the next traffic light is in the red phase. We apply this algorithm to construct decision trees that enable two driving behaviors: aggressive and careful. The focus of this study is to analyze the amount of aggressive drivers that are needed in order to generate a traffic gridlock in a portion of a city with signalized intersections. At rush hour, aggressive drivers will enter the intersection regardless if they have enough time or space to clear it. When their traffic light changes they block other drivers, thus providing the conditions for a gridlock to develop. We find that gridlocks emerge even with very few aggressive drivers present. These results support the idea of promoting good driving behavior to avoid heavy congestion during rush hours.

Temperature and Stress Fields of Anchorage Mass Concrete of a Suspension Bridge

Because of its huge volume, the method of block and layer pouring is usually used in the construction process of suspension bridge anchorage. In order to avoid the temperature cracks of mass concrete caused by hydration heat in the construction process, a three-dimensional finite element model is established based on the anchorage of a suspension bridge. The influences of the temperature of mixture placing to mold, the thickness of layers, the ambient temperature and the maintenance measures on the temperature at the centre, the temperature difference between the top surface and middle point and the tensile stresses at the surface are analyzed. The results show that the temperature at the centre, the temperature difference between the top surface and middle point increase with the increase of the temperature of mixture placing to mold and the thickness of layers are positively correlated. When the temperature of mixture placing to mold changes from 15°C to 35°C, the temperature at the centre increases by 19.06°C, the temperature difference between the top surface and middle point increases by 10.85°C, and the tensile stresses at the surface increases by 0.72 MPa; when the thickness of layers increases from 1 m to 3 m, the temperature at the centre increases by 15.46°C, the temperature difference between the top surface and middle point increases by 16.87°C, and the tensile stresses at the surface increases by 1.51 MPa. The temperature difference between the top surface and middle point decrease with the increase of the ambient temperature, while the temperature at the centre increases with the increase of the ambient temperature. Moreover, the temperature difference between the top surface and middle point decrease with the improvement of curing conditions. Therefore, in the actual project, reducing the temperature of mixture placing to mold, the reasonable layer thickness, the suitable ambient temperature and good maintenance measures, which can effectively reduce the cracking risk of mass concrete.

A Novel Genetic Trajectory Planning Algorithm With Variable Population Size for Multi-UAV-Assisted Mobile Edge Computing System

This paper presents a multi-unmanned aerial vehicle (UAV)-assisted mobile edge computing (MEC) system, where multiple UAVs (variable number of UAVs) are deployed to serve Internet of Things devices (IoTDs). We aim to minimize the sum of hovering and flying energies of UAVs by optimizing the trajectories of UAVs. The problem is very complicated as we have to consider the deployment of stop points (SPs), the association between UAVs and SPs, and the order of SPs for UAVs. To solve the problem, this paper proposed a novel genetic trajectory planning algorithm with variable population size (GTPA-VP), which consists of two phases. In the first phase, a genetic algorithm (GA) with a variable population size is used to update the deployment of SPs. Accordingly, a multi-chrome GA is adopted to find the association between UAVs and SPs, an optimal number of UAVs, and the optimal order of SPs for UAVs. The effectiveness of the proposed GTPA-VP is demonstrated through several experiments on a set of ten instances with up to 200 IoTDs. It is evident from the experimental results that the proposed GTPA-VP outperforms the benchmark algorithms in terms of the energy consumption of the system.

Комп’ютерне моделювання руху пасажирського транспорту на зупинних пунктах міських маршрутів

The paper investigates the problem of optimization of public transport traffic based on simulation. The aim of the work is to assess the operational characteristics of the urban public transport organization system to meet the transport needs of city residents. A discrete simulation model for organizing the movement of passengers and route vehicles at a bus stop has been built. The vehicle in conjunction with the bus stop is considered as a multi-channel queuing system with failures. An algorithm for determining the average waiting time of passengers in a queue and an algorithm for determining a rational time interval between route vehicles arriving at a bus stop have been developed. The number of free seats in the route vehicle is set as a random variable. The algorithms are based on the use of dynamic data structures, in particular, queues of limited length. In addition to the maximum and current length, the queue structure includes an array whose elements are the time intervals between the appearance of passengers at the stopping point. In this case, the intervals between the addition of the next passenger to the queue change depending on the time of day. The model is implemented on the example of stopping points on one of the bus routes in Cherkassy using an object-oriented programming paradigm. The software project was executed using the C ++ language in the fully functional Visual Studio 2019 application development environment. The application of the proposed model in the reorganization of public transport allowed to reduce the average waiting time for passengers from 11 minutes to 9 minutes and to develop recommendations on how to solve the problem of overcrowding at stop points during peak hours, which is especially important during the quarantine period due to the spread of Covid-19.

Религия и миф как принципы культуры и переживание времени

The article is focused on the emergence of culture from religious and mythological grounds, which is one of the traditional problems of cultural studies. The author analyses the religious principles of culture by considering how the archaic consciousness experiences time. The author considers the special meaning of time and of the nature of time awareness which generates the development of culture. The empirical data of the cultural sciences and their theoretical generalisations show that the origins of cultural representations of humanity should be sought in its religious past. As O. Spengler noticed, the religious past is underpinned by a unique experience of religious myth which is repeated many times during the course of cultural genesis. Myth constitutes an early form of the unity of the world through which order and lawfulness are established in existence, while religion is the very first and fundamental principle of the constitution of the unity of being. Time is the primary condition for distinguishing between the sacred and profane, but it is perceived quite differently from the way objective time is perceived. In prehistoric time, mythical temporality does not distinguish between “before” and “after” — everything exists in “eternal now”, because the event to which the myth refers is a stopping point, Arche as the absolute principle of the origin of things. Time is an existential marking, a form of changing the sacred events of life and a form of human existence. The openness of profane time to the sacred one provides access to Absolute as a constitutive principle of the universe.

ЗБІР ТА АНАЛІЗ ДАНИХ ДЛЯ ОРГАНІЗАЦІЇ ПЕРЕВЕЗЕНЬ У МІСЬКІЙ ПАСАЖИРСЬКІЙ ІНФОРМАЦІЙНО-ТРАНСПОРТНІЙ СИСТЕМІ

У запропонованій роботі розглядається концептуальна модель організації перевезень у міський пасажирській інформаційно-транспортній системі на базі безпілотних транспортних засобів. Інформаційно-транспортні системи є новим поколінням транспортних систем, що базуються на активному використанні інформаційних технологій та інтелектуальних алгоритмів для організації перевізного процесу. Особливістю даної міської пасажирської інформаційно-транспортної системи є те, що такі процеси як прогнозування, планування і управління перевезеннями, на яких будується організація роботи будь-якої транспортної системи, здійснюються в режимі реального часу, що дозволяє транспортній системі адаптивно реагувати на зміни попиту на перевезення. В роботі розглянуті не тільки структура і принципи функціонування транспортної системи, але і структура та принципи функціонування її інформаційної складової (єдиного інформаційного сервера), що є основою для прийняття рішень і організації перевезень: розглянуті принципи побудови процесу збору та аналізу заявок для складання плану перевезення пасажирів, який формується не тільки з урахуванням вже зареєстрованих в системі заявок, але і з урахуванням потенційних заявок на перевезення, які можуть надійти в транспортну систему до моменту появи транспортного засобу на зупиночному пункті. Запропоновано метод розрахунку прогнозного значення кількості потенційних заявок, який використовується для складання плану перевезення, і описана концепція його програмної реалізації через використання можливостей системи управління базами даних часових рядів, здатної до високопродуктивної вставці даних, в якій потік заявок записується і зберігається у вигляді дискретного часового ряду - сукупності послідовних спостережень, кожне з яких має свою тимчасову мітку, яка має його на осі часу. Запропоновані рішення мають на меті підвищення якості та своєчасності обслуговування пасажирів і одночасно дозволяють максимально ефективно використовувати рухомий склад і енергоресурси міської пасажирської інформаційно-транспортної системи.

A Semantically Sensitive Privacy Protection Method for Trajectory Publishing

Trajectory data set is the indispensable foundation for constructing reliable Internet of Vehicles (IoV) service and location-based service (LBS), while it is likely to be abused by malicious attackers to infer user’s privacy. In this paper, we propose a trajectory protection method based on stop points obfuscation, which can confront various privacy attacks and preserve the semantic information to achieve adequate utility. Two strategies for stop point selection are designed, including category-distance priority method and Markov matrix method. Our new method was analyzed and evaluated on a real-world trajectory data set. The experiment result shows that our method can improve the utility of the data set and provide multi-level privacy protection.

Результаты экспериментальных исследований расхода топлива с учетом скоростных режимов движения городских автобусов

At the moment, there is a large number of dissertations and scientific works covering the issues of traction-speed and fuel-economic characteristics of vehicles, the results of which are presented in the form of: regression models, approximating dependencies, mathematical models based on multivariate analysis, including a number of additional coefficients. In this connection, the use of the results of these works in practice is limited, since it requires high qualifications of the МTЕ personnel and the use of special software and hardware. At the same time, at the department “Automobile transport” NSTU named after R. E. Alekseev developed a probabilistic-analytical method for predicting fuel consumption by road trains, considering the high-speed mode of movement, which shows a high convergence of results with actual average speeds only for uniform movement of buses with a constant average speed, which is not applicable to the assessment of fuel consumption of city buses. Based on the hypothesis put forward on the applicability of the Weibull-Gnedenko distribution for calculating the average speeds of city buses and the normal distribution for calculating accelerations during movement, the tasks of this study are formulated, expressed in the development of mathematical models reflecting the dependences of speeds and accelerations during bus movement in urban operating conditions, for planning their fuel consumption. To solve the set tasks, the following experimental studies were carried out: determination of the average coefficient of total road resistance; the actual distribution of speeds and accelerations when driving city buses; determination of the average actual value of fuel consumption when the bus is moving and when idle at stopping points. Based on the results of processing experimental studies, the possibility of using the Weibull-Gnedenko law to describe the actual speeds in urban conditions and the normal law to describe accelerations when driving city buses was confirmed, which allows planning fuel consumption using the analytical apparatus of the theory of probability and mathematical statistics and using the developed methodology in practice of motor transport enterprises. Based on experimental studies and theoretical studies in this area, an analytical method for planning fuel consumption for city buses, considering the speed of their movement, has been developed, which allows planning fuel consumption without additional experiments. Carrying out such studies for other types of motor vehicles and assessing unaccounted for indicators of road, transport and natural-climatic operating conditions will create a generalized analytical method for planning fuel consumption by vehicles in various operating conditions.

Temnić Inscription from Balkan-Slavic and Old Russian Perspectives

The Temnić inscription is the oldest surviving written record of Slavic discovered on the territory of Serbia (the region of Temnić), however, the original provenance of the inscription is unknown. The tablet with the inscription (ca. 20 x 20 cm) was made of the limestone absent from the area where it was found, and thus the plate could have been brought from any other region. The Temnić inscription dates to the end of 10th-11th centuries, while other written records of Cyrillic script in Serbia, Bosnia and Croatia are at least one and a half century younger, moreover, the Temnić inscription was found on the north from the Serbian, Bosnian and Croatian lands where Cyrillic writing spread in the 11th–12th century. The linguistic peculiarities of the inscription are too archaic in comparison with Church Slavic Glagolitic manuscripts of north Macedonian, east Serbian or Croatian provenance: it shows correct use of the letters for both jer-vowels and ы–и as well, which implies that hard and soft consonants did not yet merge in the dialect of unknown scribe. The inscription shows traits of higher varieties of Church Slavic: it presents jotized letters, a special sign for palatal consonant ĺ (ꙥ), stop points in the middle of the lines between the word forms which share common accent. These features are absent from Cyrillic epigraphic of Serbian, Bosnian and Croatian provenance, while the sign for palatal ĺ (ꙥ) appears in a single Old Bulgarian manuscript and in numerous east Slavic sources which go back to Old Bulgarian archetypes. While surviving Serbian writing provides no witness to Serbian origin of the inscription, its linguistic features perfectly correspond with manuscripts and inscriptions of Old Bulgarian provenance, and with East Church Slavic writing which goes back to Old Bulgarian sources. Consequently, linguistic data testify to the Old Bulgarian provenance of the Temnić inscription. Besides the provenance of the inscription, the author discusses regressive palatal accommodation of l after k which remained unknown in the south Slavic historical phonetics by far. The Temnić inscription shows this phenomenon along with other Old Bulgarian and Old Russian Church Slavic manuscripts. Finally, the article provides a new interpretation of three obscure passages in the Temnić inscription and presents its reliable transcription.

General guidelines for the design of BRT routes in the Public Transport Integrated System of Bogotá

The objective was to establish general guidelines for the design of the BRT route network in Bogotá’s Public Transport Integrated System – SITP – in terms of geographical layouts, stop points, and frequencies. The demand for the morning rush hour in a typical business day before COVID-19 was contemplated.The research methodology had three phases. 1) Establish several sets of preliminary guidelines for route network design in the Bogotá BRT System – TransMilenio –. 2) Development of a methodology – based on a transport model implemented in PTV-Visum – to assess different routes scenarios designed following those sets of preliminary guidelines. 3) Application of this assessment methodology to quantify the impact of each set of preliminary guidelines for route network design. The main output consists of selected guidelines for the design of route network in TransMilenio. Among the conclusions, the BRT services in Bogotá should be designed with a multi-criteria approach, which implies a relatively complex route network. A very simplified route network has proven to be inconvenient. On the other hand, in the short term, it is recommended to maintain diametrical routes to avoid the collapse of central stations due to increased transfers. However, in the medium term, the paradigm must evolve to radial routes design. This approach would make it possible to significantly reduce the minimum required fleet, improving headways, increasing comfort within buses, and/or reducing investment in rolling stock. Furthermore, it has been shown that the radial routes approach would require four new central interchange stations in Bogotá.