Eddy current testing (ECT) is an efficient method to estimate the thickness of sample but it is affected by other parameters information including electromagnetic properties and lift-off. In the ...previous researches, the lift-off point of intersection (LOI) feature has been found in pulsed eddy current (PEC), which can overcome the fluctuation of lift-off. In this paper, another feature, i.e. conductivity point of intersection(CPI), is proposed for non-coaxial T-R sensor in PEC. Specifically, the response signals of different sample conductivity almost intersect with each other at the certain time, which can be regarded immune to the conductivity of sample. The analytical solution and numerical solution are conducted, and the results indicate that the intersection point magnitude is mainly related with parameters of sensor and thickness of samples. Considering the elements related with conductivity in the Hessian matrix exists ill-conditioning, it will produce the magnification of measurement error under iterative inversion process. By referring to the CPI feature, the thickness of the sample and lift-off of sensor can be accurately inverted based on the modified Newton-Raphson method. The experiments are carried out to verify the proposed method, and the error is only 2.9%.
To elucidate the molecular mechanisms underlying genetic variants identified from genome‐wide association studies (GWAS) for a variety of phenotypic traits encompassing binary, continuous, count, and ...survival outcomes, we propose a novel and flexible method to test for mediation that can simultaneously accommodate multiple genetic variants and different types of outcome variables. Specifically, we employ the intersection–union test approach combined with the likelihood ratio test to detect mediation effect of multiple genetic variants via some mediator (e.g., the expression of a neighboring gene) on outcome. We fit high‐dimensional generalized linear mixed models under the mediation framework, separately under the null and alternative hypothesis. We leverage Laplace approximation to compute the marginal likelihood of outcome and use coordinate descent algorithm to estimate corresponding parameters. Our extensive simulations demonstrate the validity of our proposed methods and substantial, up to 97%, power gains over alternative methods. Applications to real data for the study of Chlamydia trachomatis infection further showcase advantages of our methods. We believe our proposed methods will be of value and general interest in this post‐GWAS era to disentangle the potential causal mechanism from DNA to phenotype for new drug discovery and personalized medicine.
The surface–surface intersection is a fundamental task in CAD/CAM. We present the classification and a full enumeration of the topology of all non-degenerate intersections of two Dupin cyclides. ...Inversion geometry is first used to transform the intersection of two Dupin cyclides to that of a cyclide and a torus. Then the topology of the intersection curve is reduced to the arrangements of the main circle of the torus and another pair of circles, which can be characterized by a simple algebraic sequence. Based on the classification and enumeration results, an efficient determination algorithm for the topology of two Dupin cyclides is also provided.
•For non-degenerate intersections of two Dupin cyclides we provide: 1. A classification and a full enumeration based on a simple algeberaic sequence;2. An efficient and robust algorithm of determining the intersection topology.
Modeling of traffic parameters is a fundamental aspect of solving various traffic and transportation problems. Among them, the speed of the vehicle is often used to evaluate different traffic stream ...parameters. A detailed investigation of vehicular speed is extremely required in modeling various stream parameters both in theoretical and simulation-based approaches. Speed is a continuous random variable, and most of the studies proposed a normal distribution to describe speed distribution characteristics. However, in a mixed traffic stream, the speed distribution deviates from the normal distribution due to the heterogeneity. Therefore, an extensive investigation of speed distribution characteristics is carried out at signalized intersection under mixed traffic scenarios. A total number of 16 four-legged signalized intersections were selected from four different metro cities (Delhi, Kolkata, Bhubaneswar, and Jaipur) for detailed analysis of speed distribution. Six different distribution models, namely normal, log-normal, gamma, beta, burr, and generalized extreme value (GEV) distributions, are considered to find out the speed distribution model. It is observed that burr and GEV distributions are found most suitable to model empirical speed distribution for mixed traffic environment. Whereas, the GEV distribution shows above 90% fit percentage to describe the speed distribution for each location and each vehicle type. Besides, the normal and log-normal distributions are found least appropriate. Therefore, novel ranking method is proposed as per the goodness of fit result obtained by the Kolmogorov–Smirnov (K–S) statistical test. It is found that the GEV is proven to be appropriate fitting distribution among the other selected distribution model to represent speed distribution for each vehicle type as well for any vehicle composition level. Thus, the present study provides new statistics of speed distribution model that would be beneficial for researchers and engineers to choose most suitable distribution model in modeling vehicular speed at signalized intersections.
•Speed distribution characteristics is analysed for mixed traffic at intersections.•Six continuous hypothesized distributions are considered.•K-S test is adopted to verify the aptness of the distribution models.•A ranking method is implemented to determine the suitability of each distribution.•GEV distribution shows suitable fitting with 90% above fit percentage.
Purpose: An increase in the number of vehicles that are not matched by the growth of road area is one of the causes of road Traffic congestion in Batam City. Traffic congestion occurs, especially in ...business and densely populated residential areas. The government has carried out various engineering and traffic management to keep the road service level under control. This study aims to analyze traffic management's efficiency in reducing Traffic congestion on roads in Batam City.
Design/methodology/approach: This study uses a case study at the Bengkong red light intersection, Batam City. The analysis was carried out using The Indonesian Highway Capacity Manual-1997.
Findings: Traffic management and engineering must be implemented gradually to get a suitable implementation model. Actual conditions in the field become essential in determining the right choice of traffic management and engineering.
Research limitations/implications: Traffic management and engineering analyzes were conducted locally at the case study site.
Practical implications: The analysis of traffic management reduces traffic congestion's impact.
Originality/value: Original paper
Paper type: A case study
Due to the characteristics of urban vehicular ad hoc networks (VANETs), many difficulties exist when designing routing protocols. In this paper, we focus on designing an efficient routing strategy ...for vehicle-to-vehicle (V2V) communication in urban VANETs. Because, the characteristics of urban VANET routing performance are affected mainly by intersections, traffic lights, and traffic conditions, we propose an intersection-based distributed routing (IDR) strategy. In view of the fact that traffic lights are used to cause vehicles to stop at intersections, we propose an intersection vehicle fog (IVF) model, in which waiting vehicles dynamically form a collection or fog of vehicles at an intersection. Acting as infrastructure components, the IVFs proactively establish multihop links with adjacent intersections and analyze the traffic conditions on adjacent road segments using fuzzy logic. This approach offloads a large part of the routing work. During routing, the IVFs adjust the routing direction based on the real-time position of the destination, thus avoiding rerouting. Each time an IVF makes a distributed routing decision, the IDR model employs the ant colony optimization (ACO) algorithm to identify an optimal routing path whose connectivity is based on the traffic conditions existing in the multihop links between intersections. Because of the high connectivity of the routing path, the model requires only packet forwarding and not carrying when transmitting along the routing path, which reduces the transmission delay and increases the transmission ratio. The presented mathematical analyses and simulation results demonstrate that our proposed routing strategy is feasible and that it achieves relatively high performance.
We propose a novel two-party private set intersection (PSI) protocol, which achieves ideal and constant receiver-to-sender and linear sender-to-receiver communication overhead, linear computational ...complexity, along with receiver size-hiding and lightweight computation cost. In comparison with other PSI protocols, the proposed protocol is more practical as it does not require any fully homomorphic computation. We propose three variants to demonstrate efficiency optimization, size-hiding feature extension, and online/offline settings for real-world applications, respectively, to offer a practical control between security and efficiency. Finally, we prove that our proposed protocols are secure against malicious participants under our security model.
As urban traffic condition is diverse and complicated, maximizing the use of urban traffic signal control system to solve traffic issues becomes one of the hot and promising topics. Especially, how ...to control traffic signals at multiple intersections is a key challenge. To speed up urban traffic flow, this research presents a genetic timing scheduling model (GTSM) for urban traffic signal control. GTSM constructs cellular automata to update the timing cycles of traffic signals at multiple intersections, where state update functions are formulated to coordinate traffic signals. In addition, a proposed genetic optimization algorithm (GOA) in GTSM optimizes the timing cycles of traffic signals at multiple intersections in the dynamic timing optimization. The experimental results on urban road networks show that the performance of our model is excellent in various scenarios to control traffic signals to speed up urban traffic flow.
•A significant proportion of road trauma occurs at intersections.•Systemic applications in intersection design are sparse.•We use systemic Ergonomics methods to evaluate two intersection ...designs.•Application revealed unanticipated emergent behaviour induced by future design.•Unaware of emergent behaviour, design induced problems remain untouched.
While a safe systems approach has long been acknowledged as the underlying philosophy of contemporary road safety strategies, systemic applications are sparse. This article argues that systems-based methods from the discipline of Ergonomics have a key role to play in road transport design and evaluation. To demonstrate, the Cognitive Work Analysis framework was used to evaluate two road designs – a traditional Melbourne intersection and a cut-through design for future intersections based on road safety safe systems principles. The results demonstrate that, although the cut-through intersection appears different in layout from the traditional intersection, system constraints are not markedly different. Furthermore, the analyses demonstrated that redistribution of constraints in the cut-through intersection resulted in emergent behaviour, which was not anticipated and could prove problematic. Further, based on the lack of understanding of emergent behaviour, similar design induced problems are apparent across both intersections. Specifically, incompatibilities between infrastructure, vehicles and different road users were not dealt with by the proposed design changes. The importance of applying systems methods in the design and evaluation of road transport systems is discussed.
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