Alignment Design Research Articles

Dynamic Response of Curved Tunnels under Vertical Incidence of Transversal SV Waves

Long tunnels often have curved sections when alignment designs are influenced by topography, adverse geology, and environmental factors. When the transversal SV wave is incident vertically, the curved section of the tunnel is subject to a connection between longitudinal and transversal loads, which are asymmetrical about the tunnel longitudinal axis. Compared to straight tunnels, curved tunnels are more complex in terms of forces and deformations and may become a key control section limiting the seismic safety of curved tunnels. To investigate the seismic response of curved tunnels, numerical simulations of curved tunnels with different radii of curvature under transversal SV seismic waves were carried out in this study. Local artificial boundaries were programmed and used for the 3D rock tunnel interaction system model to simulate semi-infinite rock and to eliminate fake reflections of seismic waves on local boundaries. The results show that longitudinal deformation and cross-sectional deformation occurred simultaneously in curved tunnels when the transversal SV wave was incident vertically. As the curvature increased, the longitudinal deformation of the curved tunnel increased. The cross-section of the tunnel was in oblique compression, and the cross-sectional internal force showed significant asymmetry. When the radius of curvature was 250 m, the difference in bending moment between the left and right haunch was 35.2%. These characteristics differ from those of straight tunnels and should be paid attention in the seismic design of curved tunnels.

End-to-end BIM-based optimization for dual-objective road alignment design with driving safety and construction cost efficiency

Road alignment design is crucial to ensure driving safety. The application of BIM technology increases efficiency and reliability in the road design process. However, it is challenging to consider multiple factors in BIM-based road alignment design. This study proposed an optimization design framework considering driving safety and road construction costs using BIM. A fast and reliable parameterization method was developed for road alignment. The BIM technique was used for modeling and earthworks statistics. The automated driving simulation was performed using MATLAB to quantify driving safety, and NSGA-II was used to solve the optimal alignment. The entire data interaction procedure is end-to-end. The framework was applied to the design project of the Phnom Penh-Sihanoukville highway. The proposed optimization method results show a combined improvement of 6.6% compared to the expert design results.

Gate-controlled photoresponse improvement in b-AsP/WSe2 heterostructures with type-I band alignment

As a promising two-dimensional (2D) layered material, black arsenic phosphorus (b-AsP) alloys have received growing attention due to their unique properties and their ability for high-performance broadband photodetection. However, high dark current and slow response speed have already become bottlenecks for further development. Manual vertical van der Waals heterojunctions made of different 2D materials offer opportunities to alleviate such bottlenecks in a simple and low-energy way. The rational design of band alignment can facilitate device performance. In this work, we design and achieve a type-I vertically stacked WSe2/b-As0.084P0.916 device, which exhibits a rectification ratio of 102 along with an unusual backward current as low as 10−12 A. As such, this device can function as an ultrasensitive photodetector, which shows excellent photoresponse properties from the visible to near-infrared region (275–850 nm), with a responsivity of 244 A/W, a specific detectivity of 2.27 × 1012 Jones, and a fast response speed of τrise ≈ 5.1 ms and τdecay ≈ 4 ms. Compared to the dark state, the hole mobility under light stimulation is raised more than ten times (from 1.1 to 12.1 cm2 V−1 s−1), which contributes to numerous excited electron–hole pair transfers from WSe2 to b-As0.084P0.916. The responsivity and detectivity increase by 5 and 3 orders of magnitude, respectively, after applying gate voltage, indicating remarkable gate-controlled properties. These results suggest that the WSe2/b-As0.084P0.916 heterostructure is a promising candidate for future electronic and optoelectronic applications.

Geometric Design for Damar Wulan Road Deli Serdang Regency

Damar Wulan Road is one of the 3.5 km road sections located in Sampali Village, Percut Sei Tuan District, Deli Serdang Regency. This road has the potential to be an access to a strategic location, but there are still few people who use Damar Wulan Road as a mobilization route because most of the road is still subgrade. Therefore, it is necessary to design the Damar Wulan Road so that it can be used by the community. This study aims to design vertical alignment for Damar Wulan Road. The method used for vertical alignment design is TPGJAK 1997. The calculation on the vertical alignment obtained results in the form of 16 PVI arches, which are 8 convex vertical curves and 8 concave vertical curves.

The Geometric Design of Horizontal Alignment: A Case Of Post-Harvest Infrastructure Corn Drying Center, Tuban, East Java

One of the aspects put forward in modern times is road infrastructure to meet the needs of moving goods, services, and people. As well as road planning for toll roads, connecting roads between regions, and roads in specific areas such as industrial areas, it also requires careful planning to meet the needs of transportation movement in them. This analysis focuses on the geometric road planning for horizontal paragraphs in the Corn Drying Center Post-Harvest Infrastructure industrial area in Tuban, East Java. The planning considers daily vehicle flows, heaviest axis loads, and bend radiuses that adjust for a limited land area. Correspondence to data in the field is obtained from the results of surveys that have been conducted (quantitative data). The result of the calculations is depicted using AutoCAD Civil 2D®.

Accelerating Minimap2 for Accurate Long Read Alignment on GPUs.

Long read sequencing technology is becoming increasingly popular for Precision Medicine applications like Whole Genome Sequencing (WGS) and microbial abundance estimation. Minimap2 is the state-of-the-art aligner and mapper used by the leading long read sequencing technologies, today. However, Minimap2 on CPUs is very slow for long noisy reads. ~60-70% of the run-time on a CPU comes from the highly sequential chaining step in Minimap2. On the other hand, most Point-of-Care computational workflows in long read sequencing use Graphics Processing Units (GPUs). We present minimap2-accelerated (mm2-ax), a heterogeneous design for sequence mapping and alignment where minimap2's compute intensive chaining step is sped up on the GPU and demonstrate its time and cost benefits. We extract better intra-read parallelism from chaining without losing mapping accuracy by forward transforming Minimap2's chaining algorithm. Moreover, we better utilize the high memory available on modern cloud instances apart from better workload balancing, data locality and minimal branch divergence on the GPU. We show mm2-ax on an NVIDIA A100 GPU improves the chaining step with 5.41 - 2.57X speedup and 4.07 - 1.93X speedup : costup over the fastest version of Minimap2, mm2-fast, benchmarked on a Google Cloud Platform instance of 30 SIMD cores.

Data Alignment Design for Robotic Programming by Demonstration Based on IMU and Optical Tracker

This study proposes a data alignment design for sensor fusion of an optical target (OT) and an inertial measurement unit (IMU) to track the trajectory of a handheld tool for robot programming by demonstration (PbD). A novel method is proposed for coordinate and temporal alignment between the OT and the IMU sensor to increase the tracking accuracy. The IMU measurements are aligned with the corresponding angular velocities and accelerations derived from the OT to calibrate the IMU-OT relationship. Global and local optimizations are combined to reduce the computation time for the temporal alignment and coordinate calibration. Experimental results show that the proposed method provides improved calibration results with shorter calculation time compared with two existent methods. The sensor fusion experiments verify the accuracy of trajectory tracking of 1.3mm using the calibration result, an improvement from 1.4mm of the data alignment using ruler measurement. Integrated PbD experiments by using a 6-DOF manipulator were carried out to evaluate the proposed method. The manipulator imitated the hand motion of a bottle transfer task with the trajectory error of 0.66mm. Practical robotic experiments demonstrate that the method is suitable for robot programming applications.

Settlement Models Review for Ballasted Railway Tracks as a Tool to Analyze the Influence of the Horizontal Alignment Design in the Maintenance Period

Settlement Models Review for Ballasted Railway Tracks as a Tool to Analyze the Influence of the Horizontal Alignment Design in the Maintenance Period

A bi-objective deep reinforcement learning approach for low-carbon-emission high-speed railway alignment design

Reasonable design and planning of alignments are crucial for both economic investment and the environmental impact of high-speed railway projects. Approaches that can integrate economic investment and environmental factors, thus selecting an economical and eco-friendly railway alignment, are very demanding. To address the above issue, this study focuses on optimizing a railway’s comprehensive investment, including the construction and environmental costs, as well as the railway’s life-cycle carbon emission caused by the production of building materials and the trains’ energy consumption. A novel railway alignment optimization model is formulated based on the multi-objective reinforcement learning (MORL) framework to reduce the railway total cost, accounting for both the construction cost and environmental factors. In the proposed model, a deep deterministic policy gradient (DDPG) algorithm is enhanced with an envelope algorithm that can optimize the convex envelope of multi-objective Q-values to ensure an efficient consistency between the entire space of preferences in a domain and the corresponding optimal policies. Finally, the proposed model is applied to a real-world high-speed railway project. Results show that the MORL model can automatically explore and optimize railway alignment, and produce less expensive and more eco-friendly solutions than manual work while satisfying various alignment constraints.

Assessing the Applicability of Track Alignment Design Code for Continuous Welded Rail Installation to Concrete Slab Track

In the KR code, the track alignment limitations for CWR installation are specified. These limitations appear reasonable for ballasted tracks. However, its application to the concrete slab track is doubtful because the concrete slab track has a much higher buckling resistance than the ballasted track. In addition, sometimes the track alignment cannot satisfy the KR code limitations in urban areas. Therefore, the track alignment limitations for the CWR in the KR code should be evaluated for the concrete slab track. In this study, the focus was on assessing the applicability of track alignment limitations for CWR installation in the KR code for a concrete slab track. First, a literature review was conducted to identify the basis of KR codes. Subsequently, a series of track stability analyses were performed to evaluate the applicability of the horizontal and vertical curves in the KR code to the concrete slab track. The results indicated that CWR can be installed on a concrete slab track without special limitations for the curve ranges specified in the KR code.

Study on Highway Alignment Optimization Considering Rollover Stability Based on Two-Dimensional Point Collision Dynamics

In order to reduce the influence of unreasonable road alignment design on vehicle driving safety, a study on road alignment optimization and vehicle driving safety based on two-dimensional point collision dynamics was carried out. First, through the two-dimensional point collision dynamics model, the relationship of the kinematic parameters before and after vehicle collision was deduced. Second, according to the vehicle–road coupling dynamic model analysis after collision, the safety threshold between the radius of the circular curve and the road superelevation was derived by taking vehicle rollover as the critical condition. Next, the road alignment optimization scheme based on vehicle rollover stability after collision was proposed. Finally, the rationality of the optimization scheme was verified by PC-Crash simulation. The simulation results showed that the proposed optimization scheme of the minimum radius and superelevation of the circular curve meets the safety requirements of vehicle rollover. This study optimized the relevant indicators of the road alignment under the premise of ensuring vehicle rollover stability and provides a reference for the improvement and optimization of road alignment design. It also has important guiding significance for the formulation of vehicle driving safety management measures.

Low-construction-emissions Optimization for Railway Alignment Fine-grained Designs within Densely Populated Urban Areas

Fine adjusting the existing manual railway alignment designs in densely populated urban areas to further reduce construction costs and emissions is a very challenging issue. To address this issue, this paper develops a framework of fine-grained optimization for railway alignment (FORA) to minimize the construction costs and emissions of a given manual railway design. This approach finely optimizes the alignment based on manually selected route, and proposes an improved two-level dynamic programming (DP) algorithm that incorporates the carbon dioxide emissions of buildings and railways into the objective function for calculation. Then, the proposed methodology is applied to fine-tune the alignment of a real-world railway in its preliminary design stage. The results verify that FORA effectively optimizes the railway alignment, decreasing the building demolition area, carbon dioxide emissions, and total construction cost by 7.56%, 3.42% and 3.03%, respectively, compared with the given manual route.

Measurement of pavement rutting trajectories on two-lane highway using the 3D line scanning laser system

ABSTRACT Lane departure is one of the important reasons for traffic accidents on a two-lane highway. However, the vehicles’ trajectories obtained by the traditional methods only represent wheel wandering in specifical situations, but do not reflect a regular pattern of lane departure. Pavement rutting trajectories are applied to investigate the regular pattern of lane departure in this paper. A 3D line scanning laser system is utilized to obtain 3D deformed pavement surface images, and rutting trajectories are measured based on the collected data. Inertial Measurement Unit and Distance Measuring Instrument are used to describe lane centreline trajectory of two-lane highways, and curve radius and curve length are measured. A test site on a two-lane highway is chosen as the test bed. Based on the field data, the impacts of undivided opposite lanes, curve turning direction, geometric features, curve radius and curve length on lane departure are analyzed, and the hazardous locations with large lane departures are identified. The significance of this study is that it provides a method to describe a regular pattern of lane departure on two-lane highways, and also benefits transportation agencies in traffic safety analysis and the horizontal alignment design of two-lane highways.

Unambiguous spectral characterization on triplet energy transfer from quantum dots mediated by hole transfer competing with other carrier dynamics.

Triplet generation by quantum dots (QDs)-sensitized molecules emerges great potential in many applications. However, the mechanism of triplet energy transfer (TET) is still fuzzy especially due to the complicated energy level alignment of QDs and molecules or trap states in QDs. Here, CdSe QDs and 5-tetracene carboxylic acid (TCA) molecules are selected as the triplet donor and acceptor, respectively, to form a TET system. By tuning the band gap of CdSe, the CdSe-TCA complex is exactly designed to present a Type-II like alignment of relative energetics. Coupling the transient absorption and time-resolved fluorescence spectra, all carrier dynamics is distinctly elucidated. Quantitative analysis demonstrates that hole transfer persisting for ∼ 2 ps outcompetes all other carrier dynamics such as electron trapping (∼100 ps level), charge recombination (∼ 5 ns) and the so-called "back transfer charge recombination" (∼50 ns), and thus leads to a hole-transfer-mediated TET process. The low TET yield (∼34.0%) ascribed to electron behavior can be further improved if electron trapping and charge recombination are efficiently suppressed. The observation on distinguishable carrier dynamics attributed to legitimate design of energy level alignment facilitates a better understanding of the TET mechanism from QDs to molecules as well as further development of photoelectronic devices based on such TET systems.

Customized Design of a Proposed Alignment at MAU Yola Campus in Civil 3D Using Nigerian Federal Ministry of Works Highway (FMWH) Manual

This study testedthe capability of Civil3D to design acarriageway using FMWH Manual. Forthis purpose, the guidelines outlined in the manual were accommodated. The route under consideration is a proposed dual carriageway alignment at Modibbo Adama University (MAU) Yola, Adamawa State, Nigeria. Methodology focused on field work, data acquisition, and roadway alignment design. Data for this project was obtained directly from the field using conventional ground survey method, Google Earth, GARMIN GPSMAP64 Hand Held GPS, and Kern-Swiss K1-M 292272 Theodolite. Reduce level was computed using Microsoft excel and the output was imported into the design software (Autodesk Civil 3D V.2023) as a dot csv (.csv) data file known as PENZD.csv.A simple horizontal circular curve with a radius of 200m was designed at chainage 0+268.55 to 0+290.41 between two tangents. Two Sag curves at chainages 0+160.95 and 0+655.33 were designed for the vertical alignment. A trapezoidal channel was provided to discharge storm water and also, a single cell box culvert to be sited at chainage 0+524 to 0+532.5. Equally, a pipe culvert was proposed at 0+722 to 0+723. QR Code for data used is also presented. The results indicate that the designed alignment was adequate and economical based on FMWH Manual.

Why Do Drivers' Collision Avoidance Maneuvers Tend to Cause SUVs to Sideslip or Rollover on Horizontal Curve and Grade Combinations?-An Analysis of the Causes Based on a Modified Multibody Dynamics Model.

The extent to which drivers' collision avoidance maneuvers affect the safety margins of sideslip and rollover is not captured by road geometric design theory. To quantify the effects of drivers' collision avoidance maneuvers on the safety margins of sport utility vehicles (SUVs) on horizontal curve and grade combinations, a modified 8-degree-of-freedom multibody model based on SUVs was developed. The model was then used to calculate the design safety margins of sideslip and rollover for steady states and the actual safety margins for collision avoidance maneuvers. Subsequently, the design safety margin reduction rate (the difference between the design and actual safety margins divided by the design safety margin) was calculated and used to assess the safety margins. The results showed that the safety margins of SUVs were significantly reduced by braking, lane changing, and lane changing with braking. The marginal effects indicated that the greater the deceleration and the shorter the lane change duration, the greater the effect on the safety margins, particularly the sideslip safety margin. Furthermore, when the SUV was driven at 80 km·h-1 on grades with a horizontal curve radius of 270 m and 400 m, the sideslip safety margin with emergency braking (deceleration over -4.5 m·s-2) was reduced by 71% and 21%, and the rollover safety margin was reduced by 11% and 5%, respectively. Under these conditions, an emergency lane change (lane change duration less than 2 s) caused the SUV to sideslip and reduced the rollover safety margin by 47% (curve radius 270 m) and 45% (curve radius 400 m). Therefore, drivers' collision avoidance maneuvers are a factor that cannot be neglected in alignment design.

A geographic information model for 3-D environmental suitability analysis in railway alignment optimization

Railway alignment design is a complicated problem affected by intricate environmental factors. Although numerous alignment optimization methods have been proposed, a general limitation among them is the lack of a spatial environmental suitability analysis to guide the subsequent alignment search. Consequently, many unfavorable regions in the study area are still searched, which significantly degrades optimization efficiency. To solve this problem, a geographic information model is proposed for evaluating the environmental suitability of railways. Initially, the study area is abstracted as a spatial voxel set and the 3-D reachable ranges of railways are determined. Then, a geographic information model is devised which considers topographic influencing factors (including those affecting structural cost and stability) as well as geologic influencing factors (including landslides and seismic impacts) for different railway structures. Afterward, a 3-D environmental suitability map can be generated using a multi-criteria decision-making approach to combine the considered factors. The map is further integrated into the alignment optimization process based on a 3-D distance transform algorithm. The proposed model and method are applied to two complex realistic railway cases. The results demonstrate that they can considerably improve the search efficiency and also find better alignments compared to the best alternatives obtained manually by experienced human designers and produced by a previous distance transform algorithm as well as a genetic algorithm.

Improvement of HCF life of automotive safety components considering a novel design of wheel alignment based on a Hybrid multibody dynamic, finite element, and data mining techniques

The main aim of the present study is to improve the High-Cycle Fatigue (HCF) life of automotive safety components subjected to multi-input random non-proportional loading. A case study was conducted on the automotive knuckle as one of the high-critical mechanical components of the suspension and steering systems. The steering knuckle is subjected to the highest road- and steering-induced random loads that are exerted on several points (i.e., joints of knuckle with lower control arm, steering linkage, and Macpherson strut). Moreover, incorrect adjustment of wheel angles increases the intensity of road loads. In this regard, previous studies have shown that wheel angles affect the service time of this component. In the present study, the authors attempted to present a novel design of wheel alignment to reduce the intensity of 3D stress components, and subsequently, to increase the fatigue life of the steering knuckle. To this end, a Hybrid multibody dynamic, finite element, and data mining techniques was used. Accordingly, different load histories extracted through Multi-Body Dynamics (MBD) analysis of a full vehicle model were applied on various joints of this component. Next, a transient dynamic analysis was performed, and the time histories of 3D stress fields were obtained in the critical zone. The fatigue life of the component was predicted using the Critical Plane Method (CPM) via employing the Rain-flow cycle counting technique and Miner-Palmgren damage accumulation rule. Finally, the results of Taguchi Sensitivity Analysis (TSA) were used to investigate the effect of wheel primary angles, including Camber and Toe, on the fatigue life of the cast iron knuckle. Moreover, Response Surface Method (RSM) was utilized to optimize the wheel alignment, and the cyclic lifetime of the component was compared under the pre- and post-optimization process. The results reveal that knuckle life improves by 33.66% using the optimum settings of wheel alignment.

The Trochlear Groove of a Femoral Component Designed for Kinematic Alignment Is Lateral to the Quadriceps Line of Force and Better Laterally Covers the Anterior Femoral Resection Than a Mechanical Alignment Design.

Background: A concern about kinematically aligned (KA) total knee arthroplasty (TKA) is that it relies on femoral components designed for mechanical alignment (MAd-FC) that could affect patellar tracking, in part, because of a trochlear groove orientation that is typically 6° from vertical. KA sets the femoral component coincident to the patient’s pre-arthritic distal and posterior femoral joint lines and restores the Q-angle, which varies widely. Relative to KA and the native knee, aligning the femoral component with MA changes most distal joint lines and Q-angles, and rotates the posterior joint line externally laterally covering the anterior femoral resection. Whether switching from a MAd- to a KAd-FC with a wider trochlear groove orientation of 20.5° from vertical results in radiographic measures known to promote patellar tracking is unknown. The primary aim was to determine whether a KAd-FC sets the trochlear groove lateral to the quadriceps line of force (QLF), better laterally covers the anterior femoral resection, and reduces lateral patella tilt relative to a MAd-FC. The secondary objective was to determine at six weeks whether the KAd-FC resulted in a higher complication rate, less knee extension and flexion, and lower clinical outcomes. Methods: Between April 2019 and July 2022, two surgeons performed sequential bilateral unrestricted caliper-verified KA TKA with manual instruments on thirty-six patients with a KAd- and MAd-FC in opposite knees. An observer measured the angle between a line best-fit to the deepest valley of the trochlea and a line representing the QLF that indicated the patient’s Q-angle. When the trochlear groove was lateral or medial relative to the QLF, the angle is denoted + or −, and the femoral component included or excluded the patient’s Q-angle, respectively. Software measured the lateral undercoverage of the anterior femoral resection on a Computed Tomography (CT) scan, and the patella tilt angle (PTA) on a skyline radiograph. Complications, knee extension and flexion measurements, Oxford Knee Score, KOOS Jr, and Forgotten Joint Score were recorded pre- and post-operatively (at 6 weeks). A paired Student’s T-test determined the difference between the KA TKAs with a KAd-FC and MAd-FC with a significance set at p < 0.05. Results: The final analysis included thirty-five patients. The 20.5° trochlear groove of the KAd-FC was lateral to the QLF in 100% (15 ± 3°) of TKAs, which was greater than the 69% (1 ± 3°) lateral to the QLF with the 6° trochlear groove of the MAd-FC (p < 0.001). The KAd-FC’s 2 ± 1.9 mm lateral undercoverage of the anterior femoral resection was less than the 4.4 ± 1.5 mm for the MAd-FC (p < 0.001). The PTA, complication rate, knee extension and flexion, and clinical outcome measures did not differ between component designs. Conclusions: The KA TKA with a KAd-FC resulted in a trochlear groove lateral to the QLF that included the Q-angle in all patients, and negligible lateral undercoverage of the anterior femoral resection. These newly described radiographic parameters could be helpful when investigating femoral components designed for KA with the intent of promoting patellofemoral kinematics.

An assisted decision-making tool for synchrotron beamline alignment based on neural networks

To achieve an excellent focus quality, the parameters of optical elements (OEs) are, in most of the synchrotron beamlines, manually adjusted.This procedure is not only time-consuming and experience-dependent but also extremely complex when various experimental requirements are involved.Responding to this challenge, we propose a new beamline alignment tool based on neural network-assisted design.This method can predict the parameters of OEs, according to experimental requirements.Specifically, the artificial neural network (ANN) training set is generated, based on SHADOW3 and Synchrotron Radiation Workshop (SRW) in OASYS.Then, the magnification factor (M) of the focusing lens and the position (P) of the secondary source is predicted, using the aforesaid tool.Finally, the parameters are verified by substituting back to the OASYS.The results show that learned NNs can predict the main parameters of the OEs with high accuracy (above 97%).Then bring the parameters above back to the OASYS software to obtain the re-tracing results.Furthermore, the final focused quality at the sample point satisfies the experimental design indicators.Experimental design indicators are flux, full width at half-maximum (FWHM) at the sampling point and transmission efficiency.Compared to other methods, this is a successful exploration of the ANN in the field of synchrotron beamline alignment, andit is an important guide for the design of beamlines alignment.