Maximum Travel Distance Research Articles

The optimum condition for electric vehicles’ battery powering factors to travel distance: A model-based approach

The development of electric vehicles (EVs) and their power source systems (PSS) is a rapidly growing field of technology. However, the EV's travel distance (range between charging stations) depends on the agility of the PSS, or battery capacity system. EV driving range and battery capacity are the two most significant technical challenges in commercializing EVs. This study aims to propose an integrated model that identifies the optimal energy factor orientation, enabling EVs to cover the maximum travel distance and reach the charging station for their next trip. Additionally, the artificial intelligence (AI) and statistical models were integrated and applied to predict, validate, and explain how energy factors affect the driving range of EVs. The developed models and validations revealed that maintaining precise assimilation of battery power factors can vary the EV's travel distance from 60 to 610 km. In this case, we have identified 77.5 kWh battery capacity and 14.5 kW charging capacity as the optimum power source factors. After 5.5 h of charging, various adjustments to power source factors allow for optimum battery performance. We have also proposed the central composite factorial design (CCFD) to compute the impact of energy factors on travel distance. The study used the response surface methodology (RSM) and an in-house-developed AI-based algorithm to achieve the research results. The alignment percentage between model-predicted data and real-time outputs showed an extremely high precision of over 95 % and confidence in the findings' reliability.

Mid-vastus approach induces milder short-term effects on postural control compared to parapatellar approach in total knee arthroplasty.

BackgroundMid-Vastus and Medial Parapatellar techniques are used for total knee arthroplasty. Their short-term effects within the first month after surgery are yet unexplored. The purpose of this study was to compare Mid-Vastus and Medial Parapatellar effects on knee strength and balance control, at 5 days, 2 weeks and one month after surgery. It was hypothesized that Mid-Vastus would induce milder effects on the dependent variables due to its less invasive nature. MethodsTwenty females, randomly assigned to either the Mid-Vastus or the Medial Parapatellar group performed knee flexion-extension force and 30 s of bipedal stance before, 5 days, 2 weeks and one month after surgery. Maximum force, weight distribution and travel distance of the Center of Pressure were calculated. FindingsBoth groups showed decreased force output at all post-measurements compared to before surgery. Medial Parapatellar group showcased significantly higher travel distance at the 2 weeks measurement (Z = −2.268, p = .023, |r| = 0.507) compared to before surgery. This result was also imprinted on the travel distance of the non-surgical knee limb in the post (t = 3.259, p = .004, d = 1.456), 2 weeks (Z = −2.570, p = .009, |r| = 0.574) and one month measurement (t = 2.653, p = .016, d = 1.185). InterpretationWhile force is affected for both approaches, Mid-Vastus approach does not affect postural control. Therefore, Mid-Vastus is a less invasive technique compared to Medial Parapatellar. This work highlights the differences between Mid-Vastus and Medial Parapatellar approaches at least until the first month of rehabilitation.

Estimation of Lithium-Ion Battery Health in Electric Bicycles Using Internal Resistance Measurement Method

This study evaluates the performance of a 36 Volt 10 Ah battery in an electric bicycle with a 350-Watt Brushless DC (BLDC) motor as an environmentally friendly alternative to overcome the negative impacts of motorized vehicle use in Indonesia. In addition, this study measured the State of Health battery’s value of internal resistance, which is different from other studies that use capacity fading. With a focus on maximum travel distance and travel time, experiments were conducted without load and with a 70kg load. The no-load test was conducted only once, resulting in a travel time of 600 minutes and a distance of 330.1 Km. Although the battery was not discharged, the results were not in line with expectations, so the no-load test was only conducted once. In the 70kg load test, six trials were conducted with variable measurements of distance, battery voltage, and battery resistance. Results showed variations in distance between 50.7 km and 53.1 km, and travel time between 151 and 160 minutes. The battery voltage varied from 31.316 Volts to 31.850 Volts. The resistance in the battery also showed an increase of about 0.0001 ohms from 0.1132 ohms to 0.1139 ohms. Overall, the results from the study showed that as time and usage progressed, the battery voltage and internal resistance values tended to increase, while the distance and travel time tended to decrease. The internal resistance measurement method proved to be effective in assessing battery health as the State of Health value decreased throughout the experiment.

Performance Analysis of a Single Light Source Bidirectional Visible Light Communication Reverse Reflection Link

Visible light communication has the advantages of large bandwidth, high security, and no RF interference, among which LED light sources are an important light source for indoor visible light communication. The use of LED as a light source for visible full-duplex communication is both to meet the lighting requirements and to ensure high-speed transmission of information. The uplink using the “cat’s eye” reverse modulation system can greatly reduce the system complexity of the reverse reflector. In order to analyze the factors affecting the optical power at the receiving end of the uplink of the indoor single light source visible light communication, this paper establishes the indoor visible light full-duplex communication system model and deduces the calculation method of the effective incidence angle of the uplink transmission light and the movable range of the reverse reflection end according to the model. The results show that when the link distance of the BK7 lens is 3 m, the lens aperture is increased from 100 mm to 150 mm, the lens focal length is increased from 100 mm to 150 mm, the travel distance of the reverse reflector is increased by 60%, and the effective range of the incidence angle is increased by about twice. In the absence of link loss, each 1 m increase in link distance increases the maximum travel distance of the reverse reflector by 0.8 m. Increasing the lens aperture, decreasing the focal length, and increasing the link distance can improve the movable range of the reverse reflector, and the effective incidence angle changes more gently with the position of the reverse reflector.

Identification Method of River Blocking by Debris Flow in the Middle Reaches of the Dadu River, Southwest of China

Debris flow is a typical natural disaster in the middle reaches of the Dadu River, which seriously threatens the safety of life and property of local residents. However, there is currently a lack of a comprehensive analysis methods applicable to the blockage of river channels by debris flow in the Dadu River basin, limiting disaster prevention and mitigation in this area. Based on previous large-scale model tests carried out in the middle reaches of the Dadu River, the debris flows are divided into dam-type debris flows and submerged debris flows. The calculation formulas for the maximum travel distance of the two kinds of debris flows entering the river are obtained via theoretical derivation. The formulas for calculating the length and volume of debris flow accumulation are derived, and the relationship between the debris flow loss coefficient and river blocking degree in the middle part of the Dadu River is analyzed. An identification method of river blocking by debris flow is put forward in this study. By calculating the maximum blocking degree, S (the ratio of the maximum driving distance of the debris flow to the width of the river), and the volume of the source materials needed to form a debris flow dam under the conditions that the debris flow does not reach the opposite bank (V1), reaches the opposite bank but does not block the river (V2), and reaches the opposite bank (V3), the form of debris flow blocking the river is distinguished. When S = 1, V > V3, complete blockage occurs; when S = 1, V > V2, the river is mostly blocked; when S < 1, V > V1, the river is half-blocked. This study established an identification method of river blocking by debris flow, providing a basis for early warning for river blocking and disaster prevention in the middle reaches of the Dadu River.

Integrating public perceptions of proximity and quality in the modelling of urban green space access

Access to urban green space (UGS) is associated with a number of physical and social benefits. Recognizing the importance of UGS access for people’s wellbeing, several methods have been proposed to model UGS accessibility and highlight areas underserviced by UGS. However, existing methodologies have several limitations. Models often make use of universal, normative maximum travel distances, which may not reflect the distances people actually travel to reach UGS they regularly visit. Additionally, many of these analyses do not consider UGS quality, which will largely influence use and experience of these spaces and may act as a pull factor affecting the distance people are willing to travel to visit a UGS. Those methods that do integrate quality often rely on proxies, such as size or number of amenities, and fail to consider perceived quality. To address these limitations, we propose a methodology that integrates user perception and the actual distance people are prepared to travel into a quality-accessibility (QA) analysis applied at the building block scale. Information on travel distance and quality are gathered from a public participation GIS survey conducted in the Brussels Capital Region. The results of the analysis highlight inequalities in access to specific, essential UGS experiences throughout the region. Insights provided by this analysis can help planners prioritize interventions to improve access to experiences provided by UGS in parts of the city where interventions are most needed.

Numerical and experimental investigation on condensate droplet detachment of solar still

Modifying condensing surfaces can effectively improve the vapor condensation of solar stills, while the modification impact on the condensate collection remains unclear. Here, a numerical model based on the volume of fraction (VOF) is adopted to investigate the droplet motion and detachment on the modified condensing surfaces of the still. The results show that the duration of motion, travel distance, and terminal velocity of the droplet before detachment decrease as the surface hydrophobicity increases. At an inclination angle β = 30° and contact angle θ0 = 120° (relatively high hydrophobicity), the simulation results reveal a critical detaching volume (Vc) of 53 μL and a traveling distance of 6 mm after the volume reaching Vc. The average experimental values of Vc and the distance are 49.3 μL and 19.2 mm, respectively. Based on these findings, an optimized surface with interchange hydrophilic-hydrophobic patterns is proposed and evaluated through 3D simulation. The maximum travel distance can reach 62.1 mm at β = 30°, which is 520.8% longer than that of the non-optimized surface with the same droplet volume, facilitating condensate collection. Results from this study are expected to contribute to the optimal design of condensing surfaces in solar still.

Perception of Fire safety evacuation design towards Fire Disaster in core towns of southern region of India

Old south Indian traditional towns are subjected to tremendous morphological changes. In an urban environment, fire is considered a manmade disaster. Urban pressure demands densely constructed built environments with critical fire risk parameters. In spite of various codes, building regulations that are formulated and enforced for the safety of human life and buildings, built environments in traditional areas of south India do not comply with fire safety codes and regulations. This study focuses on the perception of fire safety evacuation design by professionals who design buildings in the urban areas of south India namely “Kumbakonam, Thanjavur and Tiruchirappalli.” The fire safety evacuation parameters related to building characteristics namely number of exits, occupant load, width of exit routes/exit doors, maximum travel distance and corridor widths are considered in the present study. A structured survey has been conducted among 380 architects and engineers, who are directly involved in building designs in the aforementioned cities of south India to understand the perception of fire safety design. Therefore, this study identifies the challenges in complying existing codes and regulations, perception and knowledge in application of fire safety codes in continuous building area (CBA). In continuous building areas, the existing regulations and codes are ineffective for fire safety concern as perceived by architects and engineers. A significant percentage of respondents does not consider maximum travel distance calculation (23.15%), occupancy load (24.21%) and capacity factors calculations (33.95%) in their building design which are important determinant criteria for fire safety evacuation design during a fire disaster.

Synthesis of Biomass Corridor in Peninsular Malaysia via Hybrid Mathematical and Graphical Framework

The valorisation of biomass by synthesising a multi-biomass corridor can be an optimistic pathway to solving the growing waste management problem. However, the supply chain problem usually involves a massive number of variables, including the connectivity of the sink source and the selection of a technology pathway. In this work, a “Decomposition Approach” was utilised, wherein a P-graph was incorporated with a conventional mathematical model to reduce the number of variables. Although this type of approach is well established with respect to solving biomass supply chain problems, no previous works have comprehensively considered the effect of the maximum allowable travel distance (MATD) on a supply chain model. A case study in Peninsular Malaysia involving oil palm, paddy, and coconut biomass was conducted using the proposed approach. Moreover, a multiple linear regression (MLR) tool for formulating the cost-correlated function based on the best technology pathway obtained from a P-Graph was incorporated. As a result, the net profit of the biomass corridor was estimated to be USD 0.87 billion, with 1.45 × 107 tonnes per year of biomass being sent to 39 processing hubs over a 20-year lifespan. Furthermore, a sensitivity analysis was also conducted to investigate the impact of several cost-related parameters on the net profit.

The Impact of Ex Situ Heart Perfusion in Pediatric Transplantation: An Analysis of the OPTN Database.

Ex situ heart perfusion (ESHP) has increased the pool of donors in adults. However, this is not true in pediatrics due to lack of devices. Therefore, we sought to understand organ refusal in pediatrics and estimate donor heart usage with ESHP. Donor hearts offered to pediatrics were identified from the Organ Procurement and Transplantation Network Database (2000-2019). A linear regression model was built to predict average travel speed, and the extended maximum permitted distance with ESHP was calculated. This extended distance was compared with the policy for maximum travel distance. There were 33,708 donor offers (n = 10,807 hearts) to pediatric programs [24.1% (n = 2,604) transplanted]. Six percent of the offers (n = 1,832) (n = 771 hearts) were turned down due to distance, with 676 of the hearts never transplanted. Based on the modeling and using an ESHP time of 5.5 hours, 84% (n = 570/676) of hearts turned down due to distance could be utilized by pediatric programs. This proportion increased to 100% with 10 hours of support time. By addressing prolonged ischemic time due to distance, ESHP has the potential to increase the number of donors utilized in pediatric candidates. Although no device exists for pediatrics, this analysis lends support to the importance of developing this technology.

A Dynamic Task Allocation Framework in Mobile Crowd Sensing with D3QN.

With the coverage of sensor-rich smart devices (smartphones, iPads, etc.), combined with the need to collect large amounts of data, mobile crowd sensing (MCS) has gradually attracted the attention of academics in recent years. MCS is a new and promising model for mass perception and computational data collection. The main function is to recruit a large group of participants with mobile devices to perform sensing tasks in a given area. Task assignment is an important research topic in MCS systems, which aims to efficiently assign sensing tasks to recruited workers. Previous studies have focused on greedy or heuristic approaches, whereas the MCS task allocation problem is usually an NP-hard optimisation problem due to various resource and quality constraints, and traditional greedy or heuristic approaches usually suffer from performance loss to some extent. In addition, the platform-centric task allocation model usually considers the interests of the platform and ignores the feelings of other participants, to the detriment of the platform's development. Therefore, in this paper, deep reinforcement learning methods are used to find more efficient task assignment solutions, and a weighted approach is adopted to optimise multiple objectives. Specifically, we use a double deep Q network (D3QN) based on the dueling architecture to solve the task allocation problem. Since the maximum travel distance of the workers, the reward value, and the random arrival and time sensitivity of the sensing tasks are considered, this is a dynamic task allocation problem under multiple constraints. For dynamic problems, traditional heuristics (eg, pso, genetics) are often difficult to solve from a modeling and practical perspective. Reinforcement learning can obtain sub-optimal or optimal solutions in a limited time by means of sequential decision-making. Finally, we compare the proposed D3QN-based solution with the standard baseline solution, and experiments show that it outperforms the baseline solution in terms of platform profit, task completion rate, etc., the utility and attractiveness of the platform are enhanced.

A GIS-Based Spatial Decision Support System for Facility Location Planning in Nigeria

Abstract
 Public facilities are to be located optimally in the interest of society. In Nigeria, public facilities' locations are largely influenced by administrative constraints and politics, rather than efficiency and equity. This practice limits access, most especially, in rural communities where the population is dispersed. Studies on efficiency and equity in access to public health facilities focused on urban centres. The aim of this study, therefore, is to advance the understanding of the application of the spatial decision support system (SDSS) to evaluate efficiency and equity in access to public facilities in rural regions. The study used Ogun State, Nigeria as a case. The data used include the population and coordinates of the location of the settlements, coordinates of the location of health facilities and the transport networks. This study showed that 38.5% of settlements do not have access to primary care and the application of the p-median model showed that the efficiency of the existing location of health facilities can be improved by 40.6%. Application of the maximal covering location model showed that the existing maximum travel distance of 26.3km can be reduced. It can be reduced for the sake of equity to 9.9 km. This study demonstrated ways to develop evaluative tools for analyzing the distribution of public facilities in Nigeria. It is suggested that planners in rural regions of other developing countries can adopt these techniques and tools to make their location decisions more logical.
 Keywords: Geographic Information System, Public Health Facilities, Spatial Decision Support System, Location Efficiency, Location Equity.

A Preliminary Study on the Development of a New UAV Concept and the Associated Flight Method

This article presents a preliminary study on the development of a new concept for an unmanned aerial vehicle (UAV) design that incorporates the use of four wings and attached systems to improve overall performance, it being classified as a hybrid quadcopter (a quad tilt wing, tiltrotor UAV). By simulation, it was determined that the developed concept has significant advantages compared with a conventional quadcopter. By implementing this concept, an increase in the maximum speed by 59.21% can be obtained; it reduces time to complete a 10 km route by 36.4%, decreases the energy consumption by 37%, and increases the maximum travel distance by 56.9% at 30% remaining battery capacity. Additionally, the concept improves maneuverability by allowing turning movements to be performed by changing the angle of incidence of the rear wings, resulting in less energy consumption compared to traditional turning methods applied in the case of a conventional quadcopter.

Power Autonomy and Agility Control of an Untethered Insect-Scale Soft Robot.

It is still challenging to achieve agility and trajectory control for untethered soft robots on an insect scale given their low mechanical impedance and compact structures. In this study, fast translational movements and swift turning motions are demonstrated on a power autonomous soft robot with a piezoelectric-thin-film-actuated body and electrostatic turning footpads. A high relative running speed of 2.5 body length per second compared with existing untethered robots is realized on a 24-mm-long untethered prototype integrated with power source, control, and wireless communication modules. An arc-shaped leg structure is adopted to self-regulate the frication forces on different footpads during turning by an inclination-induced redistribution of the payload gravity on legs and footpads. The trajectory maneuverability is demonstrated by navigating a 380 mg robot prototype with an 1810 mg payload to pass through a 58-cm-long S-shaped path with wireless control in 43.4 s. Due to the flexibility of the all-polymer body structure, the robustness of the untethered robot to large strain is demonstrated when compressed by 91 times the weight of the robot. A maximum travel distance of 58.6 m is achieved for the robot equipped with a 40 mA·h lithium battery, corresponding to the cost of transport of 261. This work provides a feasible solution to achieve high agility and advance the practicability of untethered soft robots on an insect scale.

The Impact of Ex Situ Heart Perfusion in Pediatric Transplantation: An Analysis of the United Network for Organ Sharing Registry.

Ex situ heart perfusion (ESHP) has increased the pool of donors in adults. However, this is not true in pediatrics due to lack of devices. Therefore, we sought to understand organ refusal in pediatrics and estimate donor heart usage with ESHP. Donor hearts offered to pediatrics were identified from the United Network for Organ Sharing (UNOS) Database (2000-2019). A linear regression model was built to predict average travel speed, and the extended maximum permitted distance with ESHP was calculated. This extended distance was compared with the policy for maximum travel distance. There were 33,708 donor offers (n = 10,807 hearts) to pediatric programs (24.1% [n = 2,604] transplanted). Six percent of the offers (n = 1,832) (n = 771 hearts) were turned down due to distance, with 676 of the hearts never transplanted. Based on the modeling and using an ESHP time of 5.5 hours, 84% (n = 570/676) of hearts turned down as distance could be utilized by pediatric programs. This proportion increased to 100% with 10 hours of support time. By addressing prolonged ischemic time due to distance, ESHP has the potential to increase the number of donors utilized in pediatric candidates. While no device exists for pediatrics, this analysis lends support to the importance of developing this technology.

Comparison of Earthquake and Moisture Effects on Rockfall-Runouts Using 3D Models and Orthorectified Aerial Photos

Rockfall hazard gains popularity nowadays among researchers in different scientific fields, decision-makers and urban planners. The assessment of rockfall hazard requires detection, mapping and estimating the maximum travel distance that rock boulders may reach, commonly known as “rockfall runout”. This latter can change significantly under the effects of different triggering factors such as soil conditions, chemical, physical and geological rock properties. However, comparing and analyzing these different effects represents, to the best of our knowledge, one of the newest scientific challenges that need to be addressed. This paper presents a complete methodologic approach aiming to assess the rockfall hazard through runout estimation in three different conditions: (i) gravity, (ii) earthquakes, and (iii) the presence of moisture along the slope. The “Mtein” Village and its surrounding areas in the Mount Lebanon region were chosen as the study area because there have been numerous historic rockfalls and various-sized rocks, such as cobbles and boulders, scattered throughout the area. Thus, three-dimensional simulations were conducted using the Rockyfor3D software and aerial photos for the year 1999 to assess the rockfall runout, the energy curves, and the number of deposited rocks. The results reveal that earthquakes have the highest triggering effect on rockfall and that moisture has a damping effect on RFs by decreasing the kinetic energy. The study shows the importance of taking into consideration the influence of triggering factors as well as rock density on rockfall runout and hazard.

Understanding the effect of sociodemographic, natural and built environment factors on cycling accessibility

The concept of accessibility has gained considerable attention in the analysis of access to specific facilities for different populations. Unlike motorized systems in which there is no physical limit on the distance that can be traveled, the distance that a given cyclist can travel is variable and is determined by their personal characteristics and the environment. Such maximal travel distance is assumed to delimit the total extension of territory where all the potential interactions of a cyclist may take place and, therefore it affects the accessibility for people who cycle. Despite this variability in the area of influence of each cyclist, accessibility models assume, in the best of cases, a single maximum travel distance, which produces estimates of accessibility that are not very representative of reality. In this article we present more precise estimates of the accessibility of cyclists and compare them with traditional measures. The methodological improvement focuses on two aspects: (1) we calculate variable maximum distances based on the characteristics of the cyclists and the built urban environment. (2) Because the maximum travel distance depends on the characteristics of the built environment, we analyze the impact that the expansion of the dedicated cycling network has on accessibility. Our results reveal that the accessibility patterns depend on the individual characteristics and the built environment. Moreover, our results also confirm that the expansion and densification of the cycling network have an impact on the access to opportunities for cyclists that is not necessarily captured by most classical accessibility measures when considering the variability of cyclists' profiles.

Numerical Evaluation of a Novel Vertical Drop Airflow System to Mitigate Droplet Transmission in Trains

Owing to the outbreak of COVID-19, researchers are exploring methods to prevent contact and non-contact infections that occur via multiple transmission routes. However, studies on preventing infections caused by droplet transmission in public transportation are insufficient. To prevent the spread of infectious diseases, a new ventilation system in railway vehicles must be developed. In this study, a novel vertical drop airflow (VDA) system is proposed to mitigate the effect of droplet transmission in a high-speed train cabin. The droplet transmission route and droplet fate are investigated using three-dimensional fluid dynamics simulations, performed employing the Eulerian–Lagrangian model. Additionally, a porous model is adopted to simulate the effect of close-fitting masks. The results indicate that 120 s after coughing, the decrease in the droplet number in the VDA system is 72.1% of that observed in the conventional system. Moreover, the VDA system effectively suppresses droplet transmission because the maximum droplet travel distances of the VDA systems are 49.9% to 67.0% of those of the conventional systems. Furthermore, the effect of reducing droplet transmission by wearing a close-fitting mask is confirmed in all systems. Thus, the decrease in both droplet number and droplet transmission area in train cabins validate that the proposed VDA system has an effective airflow design to prevent droplet infection.

The maximal covering bicycle network design problem

Considering the lack of adequate cycling infrastructure networks in many cities, decision makers must face the challenge of designing connected bicycle facility networks to ensure safe and comfortable access to urban opportunities for cyclists and the usability of infrastructure. This paper addresses the maximal covering bicycle network design problem (MCBNDP). MCBNDP involves making investment decisions to build a cycling network that is aimed at maximizing the coverage of cyclists, while maintaining a minimum total network cost at its minimum. The derived network is subject to a budget limit and accounts for the entire connectivity and directness as fundamental bicycle network design criteria. Cyclists who are located at a given origin are considered covered by the network if a connected path of dedicated cycling infrastructure links them to their desired destination, within a maximum travel distance. We propose a mixed-integer linear programming (MILP) formulation, including a two-phase solution approach to solving the MCBNDP. In addition, using a commercial solver, our MILP formulation allows exact solutions to be obtained for large-scale instances with reasonable computing times for these types of problems. This MILP formulation is employed to solve a real instance that is applied to a wide territory of analysis in Medellin city (Colombia). The findings of this paper will contribute to existing literature and support urban policymakers to better spatially allocate the resources and, consequently, maximize the impact of their investments on connected cycling infrastructure networks. Our findings indicate that access to opportunities for cyclists can be easily favored by making small improvements to the existing infrastructure to guarantee safe, direct, and comfortable cycling infrastructure. Because we specify a maximum travel distance rather than a shortest path limitation, our problem ensures that cyclists may have several possibilities for their routes, which may go along the shortest path or any other alternative, however, without exceeding the maximum travel distance. In this direction, our findings confirm that prioritizing coverage, while accounting for full network connectivity, will benefit more cyclists because of the flexible configuration of the new network, which also may ensure its usability.

California Joins Six States in Setting Standards for MH/SUD Appointment Wait Times

California Joins Six States in Setting Standards for MH/SUD Appointment Wait Times