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The study of pedestrian catchment areas for metro stations serves as the foundation for addressing issues such as-passenger flow forecasting, land use planning around stations, and transportation link facility planning. This study aims to investigate how various factors related to pedestrians, the environment, and the characteristics of metro stations affect the areas where pedestrians are attracted to. The goal is to gain insights into design strategies and policy interventions that can enhance the appeal of metro stations. The present study considers the metro stations in the Chengdu area as the primary research objects. A framework for examining the connection between the built environment and the pedestrian catchment area of a subway station through the use of a hybrid gradient decision tree approach has been used. The study examines the pedestrian catchment areas of these stations and confirms the presence of a nonlinear relationship between pedestrian catchment areas and variables at these stations. There exists a negative correlation, within specific thresholds, between the number of companies, bus stops, and road network density with the catchment area of passengers. Concurrently, there is a positive correlation between the distances to the city center and the catchment area. Furthermore, this framework, which accounts for spatial heterogeneity, showed significant goodness-of-fit and predictive capability, aspects that were overlooked in earlier research. As a result, these research findings can serve as a key foundation for advancing the theoretical framework and statistical proof to facilitate land planning and development near metro stations, predicting passenger flow, and designing essential connecting amenities in the vicinity of such facilities., Author(s): Dong Chen [1]; Yang Kun [1]; Guo Chun (corresponding author) [2,3] 1. Introduction Metro systems account for an increasing percentage of people's daily trips [1]. To solve challenges like [...]

This paper presents a traffic flow control scheme of connected vehicles to stabilize a traffic system with on-ramps from a macromodel point of view. Firstly, this paper establishes a lattice hydrodynamic model with on-ramps, and an output feedback controller is designed based on the characteristics of connected vehicles. Then, by using the Lyapunov-Krasovskill functional analysis method, this paper studies the delay-dependent convergence conditions of the control method. String stability is defined as the nonamplification of the downstream disturbance of a traffic flow when it propagates upstream. The influence of the on-ramps is regarded as a stochastic disturbance in this paper. Through a theoretical analysis, the control conditions that can ensure the string stability of the traffic system under the influence of on-ramp are obtained. Finally, numerical experiments are carried out to compare the traffic states of the traffic system with and without control. The results show that the proposed control can effectively suppress the instability of the traffic system., Author(s): Yicai Zhang [1,2]; Min Zhao (corresponding author) [1,2]; Dihua Sun [1,2]; Hang Zhao [1,2]; Zhongcheng Liu [1,2]; Dong Chen [3] 1. Introduction With the rapid economic development and accelerating [...]

The aggregation behavior of three tadpole-shaped Polyhedral oligomeric silsesquioxane (POSS) based block copolymers using different blocks poly(methyl methacrylate) (PMMA) and poly(trifluoroethyl methacrylate) (PTFEMA) with different block sequence and ratio (POSS-PTFEMA161-b-PMMA236, POSS-PMMA277-b-PTFEMA130, and POSS-PMMA466-b-PTFEMA172) was investigated on the air-water interface. The interfacial rheology of three block copolymers was studied by surface pressure isotherm, compression modulus measurements, and compression and expansion hysteresis analysis on the Langmuir trough. The block sequence and ratio play a great role in self-assembly behavior at the interface. Based on surface pressure isotherm analysis, a thin film with low elasticity was achieved for the POSS-PTFEMA161-b-PMMA236. Moreover, for the block copolymer with same segment sequence (POSS-PMMA2-b-PTFEMA), the thin film compression capability is increased with increasing the PMMA ratio. The morphology of the deposited LB thin film was illustrated by atomic force microscopy (AFM) and X-ray photoelectron spectroscopy (XPS). We observed that a thin film was composed by crater-shaped quasi-2D micelles for POSS-PTFEMA-b-PMMA, while it was proved that only flaky texture was observed for both POSS-PMMA277-b-PTFEMA130 and POSS-PMMA466-b-PTFEMA172. The thickness and area of flaky aggregates were greatly related to PMMA ratio. The different interface self-assembly structure evolution was proposed based on the interfacial rheology and thin film morphology studies.

A wideband circularly polarized patch antenna is presented in this article. The four‐port antenna is composed of circular patch loaded with four shorting pins and cross‐shaped slot. The realization of wideband benefits from the cooperation of three resonant modes. The lowest mode is due to the resonance of half‐wavelength cross‐shaped slot, while the higher two modes are TM11 mode and TM31 mode of the circular patch, in which the TM31 mode is excited by loading four shorting pins. The L‐shaped probes are utilized to establish the coupling feed mechanism for impedance matching in a wideband range. And the compensation of the radiation null in the broadside direction benefits from the variation of the electric field distribution caused by the shorting pins and the differential L‐shaped feed structure in TM31 mode. For the aim of implementing circularly polarized radiation in the proposed patch configuration, a phase quadrature feed network consisting of power dividers and phase shifters is designed and cooperated with this antenna. In order to verify the design concept, a prototype has been fabricated, assembled and measured. The measured results show that the relative bandwidth of VSWR <1.7 and AR <3 dB is 66.7%, ranging from 2 to 4 GHz. In addition, the measured LHCP gain >3 dBic within 2.01–3.84 GHz, and the fractional bandwidth is 61%. Moreover, the peak gain is 9.9 dBic. [ABSTRACT FROM AUTHOR]

Development of highly automated and intelligent vehicles can lead to the reduction of driver workload. However, it also causes the out-of-the-loop problem to drivers, which leaves drivers handicapped in their ability to take over manual operations in emergency situations. This contribution puts forth a new switched driving strategy to avoid some of the negative consequences associated with out-of-the-loop performance by having drivers assume manual control at periodic intervals. To minimize the impact of the transitions between automated and manual driving on traffic operations, a switched cooperative driving model towards human vehicle copiloting situation is proposed by considering the vehicle dynamics and the realistic intervehicle communication in a cyberphysical view. The design method of the switching signal for the switched cooperative driving model is given based on the Lyapunov stability theory with the comprehensive consideration of platoon stability and human factors. The good agreement between simulation results and theoretical analysis illustrates the effectiveness of the proposed methods., 1. Introduction Advanced driver assistance systems (ADASs) assist drivers or take over driving tasks to operate vehicles in a safe, efficient, and comfortable way [1]. Many advanced driver assistance systems [...]

In this paper, a low‐profile and wideband circularly polarized patch antenna using four resonance modes is presented. It is one kind of four‐port antenna implemented by loading five shorting pins on the circular patch. In order to achieve wideband properties, TM11 and TM22 modes are stimulated in circular patch, along with their polarization orthogonal modes (TM11+ and TM22+ modes). The TM11+ mode is excited by the Γ‐shaped feed, while the TM22 mode and TM22+ mode is stimulated by four shorting pins in close proximity to the Γ‐shaped feed. Due to the strong coupling between shorting pins and Γ‐shaped feed, the peak electric field generated on the two opposing shorting pins causes the magnetic current density on the circumference of the patch to be changed, which in turn leads to the realization of broadside radiation in the TM22 and TM22+ modes. In addition, the function of the shorting pin loaded in the center of the patch is to improve the impedance matching when TM22 and TM22+ modes are operated. Cooperated with the devised one‐to‐four feed network with equal amplitude and progressive phase difference of 90°, the wideband circularly polarized patch antenna is obtained. To verify this design concept, a prototype is fabricated and measured. The diameter of the patch is 0.68λ0 and the profile is 0.078λ0 (λ0 is the wavelength in the free space at the center frequency). The measured relative bandwidth of VSWR < 2 is 106%, involving 1.53–4.96 GHz, while that of AR < 3 dB is 98%, ranging from 1.54 to 4.48 GHz. Besides, the measured LHCP gain > 3 dBic in the frequency band of 1.48–4.42 GHz. [ABSTRACT FROM AUTHOR]

We propose a fast data relay (FDR) mechanism to enhance existing CGRA (coarse-grained reconfigurable architecture). FDR can not only provide multicycle data transmission in concurrent with computations but also convert resource-demanding inter-processing-element global data accesses into local data accesses to avoid communication congestion. We also propose the supporting compiler techniques that can efficiently utilize the FDR feature to achieve higher performance for a variety of applications. Our results on FDR-based CGRA are compared with two other works in this field: ADRES and RCP. Experimental results for various multimedia applications show that FDR combined with the new compiler deliver up to 29% and 21% higher performance than ADRES and RCP, respectively.