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This paper expands upon the state of the art in nonlinear modeling of automotive air conditioning systems. Prior models considered only the effects of the refrigerant compressor and the condenser fan. There are two new aspects included here. First, we create a mathematical model for front-end underhood airflow, considering vehicle speed, condenser fan rotational speed, and active grille shutter position. In addition, we present a new model for the power consumption of the vehicle associated with aerodynamic drag caused by underhood flow, as well as a fan power model which accounts not only for changes in rotational speed but also changes in flow rate. The models developed in this paper are coded in MATLAB/Simulink and assessed for various vehicle driving conditions against a higher-fidelity vehicle energy management model, showing good agreement. By including the active grille shutters as a controllable actuator and the impact of underhood flow on vehicle drag and fan power consumption, control schemes can be developed to holistically target reduced energy consumption for the air conditioning system and, thus, improve the overall vehicle energy efficiency. [ABSTRACT FROM AUTHOR]

Copyright of Automobile Technology & Material is the property of Automobile Technology & Material Editorial Office and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

The automobile industry is the pillar industry of the national economy. The good operation of the automobile supply chain is conducive to the sustainable development of the economy and social economy. In recent years, the popular research of automotive supply chain disruption risk management has been widely of concern by both business and academic practitioners. It is observed that most of the literature has focused only on a particular journal or field; there is a distinct lack of comprehensive bibliometric review of two decades, of research on automotive supply chain disruption risk management. This paper delivers a comprehensive bibliometric analysis that provides a better understanding not previously fully evaluated by earlier studies in the field of automotive supply chain disruption risk management. We used the 866 journal article during the period between 2000 and 2022 from the WOS database as sample data. Highlights research topics and trends, key features, developments, and potential research areas for future research. The research problems we solved are as follows: (1) Over time, how does the research in the field of automotive supply chain disruption risk management progress? (2) Which research areas and trends are getting the most attention in the field of automotive supply chain disruption risk management? (i) to recognize the scholarly production; (ii) the most productive authors; (iii) the most productive organization; (iv) the most cited articles; and (v) the most productive countries. (3) What is the research direction of automotive supply chain disruption risk management in the future? Also discusses the shortcomings of literature and bibliometric analysis. These findings provide a potential road map for researchers who intend to engage in research in this field. [ABSTRACT FROM AUTHOR]

Politically motivated boycotts aim to harm the sales of goods associated with foreign rivals, but can also harm the domestic economy if the goods are domestically produced. This paper examines the unintended effects of the 2012 Chinese boycott of Japanese cars on China's automobile supply chain. By comparing changes in employment between auto parts and non‐parts industries located at various distances from Japanese joint ventures (JV), I find that auto parts manufacturers near the Japanese JVs experienced a 10%–17% reduction in employment after the boycott. [ABSTRACT FROM AUTHOR]

Vehicle lightweight and safety design becomes an increasingly critical issue nowadays. In order to improve the crashworthiness of side impact and roof crush with the consideration of the manufacturing process, a new composite B-pillar structure with ply drop-off is proposed in this paper. It improves the crashworthiness by changing the section thickness of structure and reduces the weight of B-pillar. The ply drop-off regions on the outer part and inner part of B-pillar are divided into three sub-laminates respectively, named as thick panel, taper panel and thin panel. The thickness of the panel are determined by the number of lay-up. Based on traditional sensitivity analysis, this paper derives some new equations and clearly evaluates and quantifies the importance of uncertainty design parameters. Finally, the comprehensive performance of the lightweight and crashworthiness for the composite B-pillar with ply drop-off is improved through structural optimization. [ABSTRACT FROM AUTHOR]

As a new model of product creation, “interactive innovation” can effectively improve the success rate of enterprise product innovation. Because of the wide application of the Internet and the pervasiveness of social media such as forums and blogs, there is a rapid growth of product reviews online. These social media platforms provide an effective channel for interactive innovation between enterprises and users. This paper is based on the innovation application of automobile products. The purpose of this paper is to identify and classify the innovative users in automobile forums and analyze the characteristics of different user groups. First, we summarize six typical characteristics of innovative users and quantify these six characteristics. Second, we make a cluster analysis of user data and divide innovative users into three classes according to the innovation value. And then, based on the different characteristics of three types of users, we present different interactive innovation methods for three types of users. Finally, we construct a pyramid model of innovative user to show the distribution status of various users. [ABSTRACT FROM AUTHOR]

The Car and Beam prototype is a teaching piece of equipment, inspired by Ball and Beam systems. It consists of a beam supported in its center by means of a rotating axis installed in two rolling bearings, allowing the beam to rotate through the actuation of a servo motor. A car is coupled to this beam, and its displacement is measured using a linear encoder. This paper focuses on two key aspects: firstly, it offers a mathematical model of the Car and Beam system, and secondly, it outlines the development of a state-feedback tracking controller through pole placement to this system. To validate the modeling and control approach, we present simulation and experimental results using three different reference profiles: step, square wave, and sine wave. Our findings demonstrate the effectiveness of the control strategy in tracking predefined trajectories, both in simulation and with the physical prototype. In conclusion, this study highlights the efficacy of the methodology employed for mathematical modeling and the controller's design in the context of this specific application. The results indicate promising potential for further exploration in this domain. [ABSTRACT FROM AUTHOR]

The contradiction between the dramatic increase in the aggregate number of automobiles and the short supply of parking spaces leads to parking difficulties. Sharing mode helps improve the efficiency of existing parking spaces, increase resource utilization, and alleviate the difficulty of parking. This paper focuses on the matching mechanism in the shared parking slots problem, which involves three agents: shared parking suppliers, shared parking demanders, and shared parking platform. We propose a prospect theory-based two-sided satisfied and stable matching model (PT-TSSM) with two objectives to maximize the satisfaction degree of both shared parking demanders and shared parking suppliers. Numerical experiments are illustrated to demonstrate the efficiency of the proposed model. Moreover, the PT-TSSM model is compared with the other two shared parking mechanisms. The proposed model considers the satisfaction degrees of both shared parking demanders and suppliers, while first book first serve (FBFS) cares only one side of the participants. And compared with deferred acceptance (DA), our model not only takes two-sided stable matching into account but also considers the satisfaction degree of all the demand and supply participants, which obtain a two-sided satisfied and stable matching scheme. [ABSTRACT FROM AUTHOR]

Purpose – The purpose of this paper is twofold: to analyze to what extent innovation output of R & D collaborations, proxied by co-patenting activities in terms of quantity, characteristics and value, differs depending on whether the engaged R & D partners have a certain type of relationship (allies, suppliers and subsidiaries); to identify possible automakers co-patenting patterns taking into account the differences in the innovation output with their R & D partners. Design/methodology/approach – To reach the aims, the authors matched two types of data: co-assigned patent portfolio of four automakers and relationship type between automakers and their co-assignees. Matching the company names of the two data sources allowed the authors to obtain the final data set used to carry out extensive descriptive and regression analysis, both on a firm- and patent-level. Findings – Results show differences in the characteristics and the technological value of patented inventions in relation with the type of collaboration partner; they also support the authors in the identification of four co-patenting patterns (contingent, purposive, watchful and advanced) according to the co-patenting propensity and the presence of a preferred relationship type. Originality/value – The paper contributes to the literature by investigating the presence of differences across the patenting activities of a selection of automakers and their supplier, allied and subsidiary firms. The issue related to patent value represents an emerging area of interest in the field of collaborations for innovation. The methodology constitutes a novelty by matching two different sources and standardizing the company names (“name game”) through an automated algorithm and a double manual check, by searching company web sites and corporate trees. [ABSTRACT FROM AUTHOR]

Among various fault types of automotive power faults, power supply UB + faults have the most complex relationship between fault signs and fault points and are difficult to diagnose. So this paper proposes a Bayesian network fault diagnosis model of automobile power supply based on fault tree. Firstly, based on the in-depth analysis of the principle of automobile power supply fault, the UB + fault tree model is constructed. The fuzzy Bayesian network model of UB + fault is constructed through the mapping relationship between fault tree and Bayesian network. Then, the prior probability of UB + fault points are obtained according to the five-year fault dataset of FAW Volkswagen Reck system, and the relevant conditional probabilities are determined by fuzzy set theory due to the lack of data and the uncertainty in expert scoring. Finally, the relevant fault point probability values are determined according to the Bayesian network inference algorithm in the case of single or parallel UB + fault sign occurring, and the fault diagnosis sequence is guided, further improving fault diagnosis efficiency. [ABSTRACT FROM AUTHOR]

In this paper, we discuss an implementation method to get high brightness and curved BLU. For 8.0inch TFT-LCD, by using the high gain film structure, particular structure surface LGP & high efficiency LED, driving with higher current, we achieve the high brightness backlight unit (BLU), which gets the brightness of 38000nit with DBEF (a reflection type polarizing film); In this paper, we also introduce a particular design, which is consist of radiating and curved structure. Radius of outer convex surface is 800milimeter, leading to the horizon angle of rear mirror expanding by about 187%, so it realizes the function of wide view mirror. [ABSTRACT FROM AUTHOR]

Proton exchange membrane fuel cell (PEMFC) stacks usually undergo vibrations during packing, transportation and serving time, in particular for those used in automobiles and portable equipment. Using finite element method (FEM), the response stress of the stack under random vibration is analyzed in the present paper. Based on the Miner fatigue damage theory, the fatigue lifes of fuel cell components (such as bolts, gaskets and PEMs) are assessed. Then the component fatigue life contours under four working conditions, i.e., the three single-axial (in x-, y- and z-axis separately) and multi-axial random vibrations are obtained. Accordingly, the component damage under vibrations in different directions is evaluated. The stress distribution on gasket and PEM will greatly affect their fatigue lifes. Moreover, comparing the fatigue lifes of 4-bolt- and 6-bolt-clamping stacks under the same total clamping force, it is found that increasing the bolt number could improve the bolt fatigue lifes. [ABSTRACT FROM AUTHOR]

Conflicts emerge when the data transmission occurs between electrical equipment in an automobile. Hence, transmission delays appear as issues. For this reason, a method, called data transmission control, for electrical equipment of automobiles based on the 5G communication technology is proposed in this paper. Firstly, the wavelet feature decomposition was utilized to partition the frequency spectrum, and thus the statistical characteristics of electrical equipment of automobiles concerning the transmitted data were obtained. Then, the high-order approximate distribution method was adopted to construct a channel for a 5G network data transmission. Afterward, the control logic structure of the data transmission was built, and the problem, called the conflict of the data transmission, was alleviated through concurrent data collection and processing methods. On this basis, coding coefficients of a constructed global coding matrix were selected to encode and transmit source information. Also, the number of redundant data packets at each layer was adjusted. Finally, the data transmission control of the electrical equipment of the automobile was realized through the linear combination of the network nodes. The simulation results showed that the throughput of the proposed method was always higher than 7.7 MB/s, the bit error rate was around 0 when the signal-to-noise ratio was lower than 3, and the transmission delay was always below 0.5 s, which could provide a reference for the efficient and safe operation of automobiles. [ABSTRACT FROM AUTHOR]

Unpredictable disruptive events significantly increase the difficulty of the management of automobile supply chains. In this paper, we propose an automobile production planning problem with component chips substitution in a finite planning horizon. The shortage of one chip can be compensated by another chip of the same type with a higher‐end feature at an additional cost. Therefore, the automobile manufacturer can divert the on‐hand inventory of chips to product lines that are more profitable in the event of shortages caused by supply chain disruptions. To cope with this, we propose a max‐min robust optimization model that captures the uncertain supplies of chips. We show that the robust model has a mixed‐integer programming equivalence that can be solved by a commercial IP solver directly. We compare the max‐min robust model with the corresponding deterministic and two‐stage stochastic models for the same problem through extensive numerical experiments. The computational results show that the max‐min robust model outperforms the other two models in terms of the average and worst‐case profits. [ABSTRACT FROM AUTHOR]

Vehicle-to-vehicle (V2V)-communication-based collision avoidance systems detect if two vehicles are on a collision course (e.g., in crossroads, intersections, and highway merging), and they are particularly useful in the absence of line of sight (LOS) owing to buildings, roadside infrastructures, and road bending. Relying on radio measurements using a 4 $\times$ 30 multiple-input–multiple-output (MIMO) system at 5.3 GHz, this paper presents the results of an empirical study of V2V propagation channels in two suburban crossroad scenarios, where vehicles are either moving in the same direction and separate from each other along different roads or pass each other in opposite directions at the crossing. The quasi-stationarity interval is first characterized using correlation matrix distance (CMD). Small-scale fading follows a Nakagami distribution based on the Akaike information criteria (AIC). Delay and angular dispersions are found to be significantly affected by the type of crossroad and the presence of an LOS. Cross-correlation coefficients between delay dispersion, angular dispersion, and small-scale fading behavior are also evaluated. By comparing the results of the different crossroads, it is found that the delay and angular dispersions are large in the first type of crossroad. By contrast, in the second type of crossroad, small delay and angular dispersions are observed due to road bending and obstruction by roadside trees. [ABSTRACT FROM AUTHOR]

Digitalization is changing the face of the automotive industry by restructuring the supply chain (SC). This study uses a systematic literature review method to analyse current and future research trends in digitalization in the automobile SC. The Scopus database is identified for carrying out this study. With the keywords search, twenty-one articles finalized for the study. This study identified the research done year-wise, the number of articles published in the journals, and the research methods used. This research provides current and future research trends. This research will benefit the automotive sector as it will help them learn about digitalization and its technology. This research offers the future of digital technology in automobile SC. [ABSTRACT FROM AUTHOR]

This study investigates electric vehicles battery recycling problem. In this study, based on Agent theory and Anylogic platform, Agent model of battery recycling is built. We have done simulation for electric vehicle batteries recycling: this paper analyses the influence that factors (battery renovation rate, quantities of electric vehicles, electric vehicle lifetime, battery lifetime, battery renovation time) have on recycling (quantities of wasted batteries, quantities of reused batteries, optimal quantities of batteries). Through simulation, this study shows that factors' influence on recycling depends on the relative life RL greatly. When renovation rate changes in the interval [0.7, 0.8], the results fluctuate greatly, such as optimal quantities of batteries will decrease about 10 %, quantities of reused batteries can increase about 30 %, and quantities of wasted batteries will have a sharp decline by about 40 %; the model is optimal until battery renovation times are increased to three. [ABSTRACT FROM AUTHOR]

Battery is a device that converts chemical energy into electrical energy and vice versa. The use of battery in automobiles started in early 1900's. In initial stages, battery was used for energizing automobile accessories like head lamps, indicators, horn etc. The recent advances has put battery for use in staring IC engine with electric start, integrating music system in automobiles, mobile charging and even in some of the high end vehicles custom inverters are build on battery that makes the vehicle suitable for camping purpose. Now a day's the battery operated electric vehicles are becoming popular which addresses the key challenges in reducing pollution. Likewise the use of battery in automobile sector has advanced through the years. The cycling of battery is done in terms of charging and discharging. Depending upon the size and specifications, the time taken to charge battery differs. This charging time layoff hampers the performance of electric vehicles. Various strategies, battery charging methods, charging stations are proposed and developed by researchers leaving behind critical issues related to the power quality to be addressed. This paper focuses on advancements in battery usages and charging in Electrical Vehicles. The power quality issues arising as a result of non linear load are presented. [ABSTRACT FROM AUTHOR]

This paper presents a novel idea on how to design an active suspension system to improve vehicle ride comfort and to actively tilt the vehicle inwards when it is subject to steering manoeuvres. Firstly, the motivations for active vehicle tilting via active suspensions are identified. Secondly, the mathematical models for the vehicle with active suspensions are built up and the link between active suspensions and vehicle roll characteristics is analysed. Thirdly, the control objectives of vehicle ride comfort and active tilting are incorporated into a standard robust-control framework and an H-infinity controller satisfying both objectives is designed. Finally, the integrated suspension control system is evaluated by computer simulations, in comparison to a passive suspension system and a traditional active one. The integrated control strategy not only improve vehicle ride comfort, but also actively tilt the vehicle inwards to act against vehicle steering manoeuvres. The active tilting reduces lateral acceleration experienced by passengers and reduces the possibility of vehicle rollover. [ABSTRACT FROM AUTHOR]

As an important scatterer in vehicle-to-X (V2X) communication scenarios, traffic signs frequently appear along roads and can affect the propagation channel appreciably. Although traffic signs can be considered as an important part in such scattering scenarios, knowledge of their bistatic radar cross section (RCS) is still absent. This paper presents an integration of the analytical models, full-wave simulation, measurement, and validation of the bistatic RCS of three types of representative traffic signs for V2X communication. First, the total RCS of the traffic signs is calculated by summing up the field contributions of the individual parts with their own phase relationships. Furthermore, simulations using full-wave analysis are performed to validate the analytical models for RCSs in the far field under plane-wave illumination. Since the high-frequency calculation techniques used here are applicable only under plane-wave excitation, the traffic-sign parts are divided into small elements, where this precondition is locally valid. Measurements are conducted in an open-area test site at the National Metrology Institute of Germany to validate the model in the near field (spherical wave from a point source). Corresponding comparisons show that the method of decomposing the traffic sign into small parts supports an effective way to embed the analytical models into ray-tracing tools, thus improving propagation modeling in V2X communication. [ABSTRACT FROM AUTHOR]

While driving, blind spot is a key phenomenon related to the visibility of the driver. Blind Spots play a vital role in road accidents. Reduction of blind spot area is very much required to reduce the accidents. In this paper, an attempt is made to overcome the problems of blind spot by optimizing the design parameters used in the rear view mirror design of heavy transport vehicles. The blind spot of the existing body structure was studied in a public transport. First the area of blind spot of the existing body structure was studied and then the optimal design parameters are ranked by Fuzzy Analytical Hierarchy Process (FAHP). FAHP was also used to determine the weights of the design parameters and ranking of the vehicle body structures though a case study. [ABSTRACT FROM AUTHOR]

Public interest in pure electric vehicles equipped with two-speed automatic mechanical transmission is increasing because of not only widened high-efficiency operation zone but also reduced speed range and cost of electric drive system. In this paper, transient dynamic behaviors of an e-drive passenger car including clutch-free two-speed automatic mechanical transmission are analyzed during up and down shifts. Bench tests for the proposed electric driveline are conducted, by which the dynamic model and the shift control strategy are validated. In experiments, severe jerking phenomena are observed when the drive motor torque sharply decreases before the separation with current gear meanwhile fast increases after the engagement with target one. For alleviation of the torsional shocks, feed-forward control in combination with optimal torque feedback control is developed for the drive motor according to torque estimation of the half shaft using extended Kalman filtering method. Meanwhile, a sliding mode control is employed for precise positioning of the shift fork for the transmission. By comparisons of the simulation and test results, it is demonstrated that the proposed control strategy reduces the jerking intensity of driveline as well as the shift period effectively in shift process. [ABSTRACT FROM AUTHOR]

Since the half-shaft is the main flexible part of the automotive driveline, the torsional dynamics of the simplified driveline considering the cubic nonlinearity of the half-shaft is discussed in the paper. The approximate solutions of the torsional shock response and the resonance response of the driveline are derived using the method of multiple scales. The stability and bifurcation condition of the responses are judged based on the Routh–Hurwitz criterion and the bifurcation theory, respectively. It is shown that the negative cubic nonlinear stiffness is propitious to suppress the torsional shock of the driveline while the positive is on the contrary. Meanwhile, the ability of the suppression of the torsional shock can be improved with the decrease in the linear stiffness. The resonance curve of the driveline may lose its stability when the value of the cubic nonlinear stiffness reaches the threshold. By properly designing the negative cubic nonlinear stiffness of the half-shaft, the instability of the resonance can be suppressed and the ability of the suppression of the torsional shock can also be improved. [ABSTRACT FROM AUTHOR]

Automakers spread on effort to maintain the crashworthiness of vehicle structures while aiming to reduce their weight. Substantial weight savings can be obtained by vehicle redesign through optimisation. Finite element based crashworthiness simulation models have contributed greatly to the optimisation of vehicle structures. These high-fidelity crash simulations may be performed many times during optimisation, thereby making optimisation studies computationally intractable. Metamodels (surrogate models) that can mimic the behaviour of the crash simulation models emerge as a solution to the computational burden. Prediction capability in metamodelling can be improved by combining many different metamodels in the form of an ensemble model. In this paper, approaches based on outlier analysis of cross validation errors are proposed to increase the accuracy of ensemble models constructed for crash response predictions. Full frontal and offset frontal crash response predictions of a c-class passenger car is used for demonstration, and it is found that the proposed approach reduces the metamodelling errors up to 12% and on average by about 4.5%. [ABSTRACT FROM AUTHOR]

Quenching technology is widely used in automotive industry from a simple immersion quenching of gears up to the complex production technology of press hardening. The selection of process parameters to develop the desired properties is challenging due to the complexity of the physical phenomena occurring during the manufacturing cycle. In the last decades several computational methods have been applied successful to optimise the heat treatment processes. This paper is focusing on some examples demonstrating the state of the art of the simulation tools, including the physical phenomena of quenching, the theoretical background of the coupled models used for estimation the microstructure, mechanical properties and deformation of heat treated automotive components. [ABSTRACT FROM AUTHOR]

Copyright of Handel Wewnêtrzny is the property of Institute for Market, Consumption & Business Cycles Research and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Using finely disaggregated data at six-digit harmonized code classification level, this paper examines the patterns and determinants of horizontal and vertical intra-industry trade in the automobile and electrical appliances sectors during the past few decades among the six major Southeast Asian countries. It is found from the analysis of the data that intra-industry trade is much higher than the inter-industry trade in each of these two sectors. Further, the determinants of these two types of trade are found to differ somewhat in terms of sign and magnitude across the sectors, implying the importance of sector-specific factors as influences on the pattern of trade. [ABSTRACT FROM AUTHOR]

Road sign detection is an important function for driver assistance systems. Although it has been studied for many years, it still has some performance limitations. This paper proposes a new method for road sign detection by employing both color and shape cues. The proposed method consists of three steps. First, the initial image is pre-processed using mean shift clustering algorithm. The clustering is carried out based on color information. Second, a random forest classifier is used to segment the clustered image. In the final step, a shape based classification is performed using a log-polar transform and cross correlation technique. The proposed detection method has been tested on both the German traffic sign detection benchmark (GTSDB) and the Swedish traffic signs (STS) datasets, and yields to 93.50 % and 94.22 % on the GTSDB dataset in terms of F-measure and area under curve(AUC), respectively. These results are satisfactory when compared to recent state-of-the-art methods. [ABSTRACT FROM AUTHOR]

Wireless local area networks (WLANs) have risen in popularity for in-car networking systems that are designed to make driving safer. Wireless mesh networks (WMNs) are widely deployed to expand the coverage of high-speed WLANs and to support last-mile connectivity for mobile users anytime and anywhere at low cost. Many recent measurement studies have shown that the traffic arrival process in wireless networks exhibits the bursty and correlated nature. A new analytical model is developed in this paper as a cost-effective performance tool to investigate the quality-of-service (QoS) of the WMN that interconnects multiple WLANs in the presence of bursty and correlated traffic. After validating its accuracy via extensive simulation experiments, the analytical model is then used to investigate the performance of the hybrid wireless networks. [ABSTRACT FROM PUBLISHER]

In the automotive industry, although small enterprises that supply car parts participate in the design phase of new car development, they do not communicate with each other for developing parts or modules because of the lack of a common communication protocol. In order to provide solutions to such problems, there has been an emergence of collaboration solutions among participants. Moreover, collaborative product lifecycle management (CPLM) is suggested as an alternative for providing such collaboration solutions. In order to develop CPLM, a framework that supports the understanding and sharing of business processes across business boundaries is necessary. Such a framework includes a reference model, business process model, and business process. The reference model explains the business domain, and it must be shared among participants for a common communication purpose. The business process model describes the collaborative design process, which can be defined by common principles in a meta-model. This paper suggests a new reference model for the design chain in the Korean automotive parts industry. Under a collaborative environment, the design process of the reference model may be classified into the mechanical and human-driven processes. In order to define both process types, a new integrated process model that combines the Component Collaboration Architecture (CCA) model of Enterprise Distributed Object Computing (EDOC) and Role Activity Diagram (RAD) models is suggested. We also introduce model driven approach (MDA) of Object Modelling Group (OMG) in order to describe an abstract level for common communication among business partners. [ABSTRACT FROM PUBLISHER]

In recent years, a lot of process innovations are strongly required for cost and weight reductions in addition to upgrading driving performance and reducing greenhouse grasses in automotive industry. In case of manufacturing automotive parts, a number of materials are used to satisfy their high accuracy and cost reduction. Dissimilar metal joint such as combination of aluminium alloy and austenitic stainless steel is increasing to apply them based on this background. In this joint, an index to guarantee the quality is indispensable, because the formation of intermetallic compounds introduces brittle fracture at the interface between two metals. It is described that plastic flow is applied for dissimilar metal (aluminium alloy and stainless steel) joint in this paper. Based on this research, it is possible to control the break point by forming projection on aluminium alloy. Projections are formed to promote the plastic flow and they are formed by keeping aluminium alloy on softening temperature. It is clear that joint boundary is composed of two reaction layers, one contains Al–Fe–Si–O and the other contains (Fe–Cr–Ni) Al3 intermetallic compound. The new process described in this paper is available for application to production line of various precise sensors for automotive parts. [ABSTRACT FROM AUTHOR]

Copyright of Journal of Mechanical Engineering / Strojniški Vestnik is the property of University of Ljubljana, Faculty of Mechanical Engineering, Journal of Mechanical Engineering and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Oscillations in the driveline of a vehicle, specifically originating from the clutch system, are referred to as clutch judder. This paper presents the design of a robust controller to actively damp these judder-induced oscillations. A DK-iteration procedure, combining H∞-controller synthesis and μ-analysis, is adopted for the robust controller design. The clutch judder model used is based on and validated with measurements on a heavy-duty vehicle powertrain. The feasibility of the control concept is evaluated by simulations and hardware-in-the-loop experiments. [ABSTRACT FROM AUTHOR]

With hybrid and electric vehicle developments, battery-monitoring systems have to meet the new requirements of the automobile industry. This paper deals with one of them, the battery's ability to start a vehicle, also called battery crankability, through battery-resistance estimation. A fractional-order model obtained by system identification is used to estimate the internal resistance of lead-acid batteries. Fractional-order modeling permits an accurate simulation of the battery electrical behavior with a low number of parameters. Moreover, the high-frequency gain of the fractional model is directly linked to the battery resistance. A resistance-estimation method based on a frequency-invalidation method is, thus, proposed. It is demonstrated that the battery's available power that defines battery crankability is correlated to the battery resistance. Thus, a battery-crankability estimator using the battery resistance is suggested. Validation tests are' carried out with various batteries. This estimator cannot be embedded in a microcontroller due to the linear-matrix- inequality-based optimization algorithm in the invalidation-model method used. A simplified algorithm is finally proposed, and its efficiency is proved. [ABSTRACT FROM AUTHOR]

Crashworthiness is one of the most important criteria in vehicle design, which often requires large-scale design analysis for a full-vehicle model consisting of many structural parts and special safety elements. The design typically involves a large number of design variables and sometimes leads to a prohibitively high computing cost. To solve this problem, this paper presents a two-stage procedure to cope with crashworthiness design of a structural frame and occupant restraint system. In the first stage, a multi-objective optimisation is carried out for structural parameters in the frontal parts without considering the details of the occupant restraint device. In the second stage, the parameters of the occupant restraint system are optimised based on an optimised structure system. In these two stages, explicit finite element and multi-body dynamics methods are employed to respectively construct response surface and Kriging model with various designs-of-experiment techniques. A full-scale vehicle model is developed to demonstrate the capability of the present two-stage design method. [ABSTRACT FROM AUTHOR]

This paper proposes a method of obstacle detection using vehicle-mounted stereo cameras. There are various objects in the road environment; these can be divided into objects, such as pedestrians, which have the possibility of colliding with the vehicle, and objects, such as road patterns, which do not have such a possibility. In this paper, an obstacle is defined as an object which is located in the space through which the vehicle will travel. In order to decide whether an object is an obstacle from the pattern in the image, it is necessary to estimate the position of the pattern in relation to the road surface. For this purpose, the planar region is determined by dynamically estimating the homography (projection transformation) matrix between the images corresponding to the plane. The pose of the camera with respect to the road is determined. Then the spatial position obtained by stereo measurement is converted to road coordinates, based on the orientation of the road surface. By applying segmentation based on the converted result of stereo measurement, obstacles are detected. On ordinary roads it is required to detect various obstacles, ranging from relatively small obstacles such as pedestrians and bicycles to large obstacles such as cars. The proposed method can detect obstacles without explicit modeling. The effectiveness of the proposed method is demonstrated by experiments using various actual images. © 2007 Wiley Periodicals, Inc. Electron Comm Jpn Pt 2, 90(12): 12–22, 2007; Published online in Wiley InterScience (www.interscience.wiley.com). DOI 10.1002/ecjb.20413 [ABSTRACT FROM AUTHOR]

In automotive powertrains, backlash imposes well-known limitations on the quality of control and, hence, on vehicle driveability. High-performance controllers for backlash compensation require high-quality measurements of the current state of the powertrain. Information about the size of the backlash is also needed. In this paper, nonlinear estimators for backlash size and state are developed, using the Kalman filtering theory. A linear estimator for fast and accurate estimation of the angular position of a wheel and the engine is also described. It utilizes standard engine speed sensors and the antilock brake system speed sensors and event-based sampling at each pulse from these sensors. The estimators are validated through experiments on a real vehicle and the results show that the estimates are of high quality, and hence, useful for improving backlash compensation functions in the powertrain control system. [ABSTRACT FROM AUTHOR]

In this paper, a kind of flow-solid sequence coupling technology for forming large aluminum alloy automotive covering parts was presented. Firstly, the numerical simulation of hydraulic bulging process was carried out. Then, the springback analysis and mold surface compensation for the simulation results were implemented. The hydraulic bulging test was made by using the optimized compensation surfaces of mold, and the hydraulic bulging parts with relatively accurate shape were obtained. The accuracy of the numerical simulation results was verified by comparing the experimental values and simulation values of the 3D deviation on the same measurement paths; then, in order to form the small fillet features in three different areas of the part, the numerical simulation and experiment research of the stamping technology were carried out on the part obtained by the hydraulic bulging process. The accuracy of the numerical simulation results was verified by comparing the experimental values and simulation values of the thickness distribution on the measurement path; finally, using the numerical simulation of fluid-solid sequence coupling forming process and the matching experiment, the changing rules of the first principal strain and the second principal strain in the small features were studied from the angle of the qualitative and quantitative analysis and it was fully verified that the small characteristics have deformed sufficiently at the end of local shaping process with the rigid die. [ABSTRACT FROM AUTHOR]

The data collection of vehicle trajectories becomes the basis of big data analysis and prediction for a variety of purposes, such as vehicle navigation and movement analysis. A digital tachograph (DTG) is pre-installed on most commercial vehicles in South Korea and is highly valuable for analyzing eco-driving metrics such as safe driving and fuel consumption estimates. In order to properly analyze a large amount of GPS location information, it is necessary to find the exact match of the location data in space to the link in the digital road network data. We previously discovered the road information of the GPS coordinates using the commonly utilized map-matching technique. However, such a navigation map-matching technique requires a lot of supplementary corrections in order to rapidly and accurately navigate a large amount of data. In this study, we applied enhanced map-matching logics with Geohash as spatial index, long link vertex division, speed filtering, azimuth filtering, and map-matching weight logics. Also, we established and implemented a distributed analysis environment for the big data map-matching with HBase (a Hadoop-based NoSQL DB). This paper shows a spatial analysis system using the map-matching logics on the Hadoop MapReduce mechanism, which improved its performance. [ABSTRACT FROM AUTHOR]

The amount of sparkle associated with automotive anti-glare display surfaces is generally worsened with increasing display resolutions. One sparkle countermeasure recently introduced by 3M is the use of an anti-sparkle optically clear adhesive (OCA). The reflection properties of the 3M anti-sparkle OCA are further investigated. [ABSTRACT FROM AUTHOR]

Originated from the future trends and requirements for silicone rubber (SR) in harsh work condition of advanced cutting-edge fields (construction, aerospace, marine equipment and automobile, etc), the processing complexity, complex ingredients and unbalanced overall properties of traditional multi-component flame-retarding SR system are limited. The development of mono-component and halogen-free flame retardants with adequate efficiency, durability and strength have been urgently expected for settling the crucial bottleneck issue of SR materials, which can avoid the defects of performance contradictions for long-used multi-component system in previous published work. Under such background, this paper has fabricated a hydrophobic Mn-doped melamine phosphate (H-DTMA@Mn) via facile multi-stage construction strategy that has been confirmed by a series of characterizations. The results have indicated that SR/28 phr H-DTMA@Mn can achieve limiting oxygen index (LOI) of 32.4% and UL-94 V-0 rating. Along with the reduced peak heat release rate, the validity of as-prepared H-DTMA@Mn for raising the flame retardancy of SR has been straightway clarified. Different from the previous work, the prominent flame retardant durability of SR/H-DTMA@Mn in many extreme environment can be maintained via the protection action of hydrophobic structure. The detailed analysis on char residues of SR composites can explain the effective flame retardant mechanism in view of chemical composition and microscopic morphology. Moreover, the mechanical strength and thermal properties of SR composites are ideal and accommodated that are greatly required in the real-life application. To sum up, the desirable balance for comprehensive performance can be realized by introducing the mono-component flame retardants, which can innately open up the innovation for meeting the requirements of SR materials in more fields. • Mono-component and Mn-doped flame retardants were fabricated for SR. • SR/28 phr H-DTMA@Mn can gain 32.4% LOI value and UL‐94 V‐0 rating. • PHRR and THR reduction of SR/28 phr H-DTMA@Mn are 42.3% and 34.7%. • Excellent balance among comprehensive properties of SR composites can be achieved. • Multi-channel synergistic flame retardant mechanism is preliminarily deduced. [ABSTRACT FROM AUTHOR]

Traditional vehicle detection algorithms do not include targeted processing to handle the vehicle occlusion phenomenon. To address this issue, this paper proposes a locally-connected, deep-model-based, occluded vehicle detection algorithm. Firstly, a suspected occluded vehicle is generated using a cascaded Adaboost Classifier. Any sub-images that are rejected during the last two stages of the cascaded Adaboost Classifier are considered as a suspected occluded vehicle. Then, eight types of vehicle occlusion visual models are manually established. The suspected occluded vehicle will be assigned to a certain type of model by color histogram matching. Finally, the sub image of the suspected occluded vehicle will be loaded into a locally connected deep model of the corresponding type to make the final determination. An experiment using the KITTI dataset has demonstrated that compared with existing vehicle detection algorithms such as the cascaded Adaboost, the Deformable Part Model (DPM), Deep Convolutional Neural Networks (DCNN) and the Deep Belief Network (DBN), this algorithm has a much higher occluded vehicle detection rate. Additionally, this method requires minimal extra processing time, at around 5 % higher than the cascaded Adaboost. [ABSTRACT FROM AUTHOR]

Elements of automobile production are frequently fabricated from ultrahigh- or high-strength steels, which ensure their considerable weight reduction and high durability, but manifest a side effect called springback. The springback value depends mostly on the material used, as well as the geometry of part being formed. Thus, in extreme cases, the deviation value from the reference part may exceed the limiting value. Prediction of springback by the trial-and-error method and subsequent deviation correction is difficult and labor-intensive. Numerical compensation methods make it possible to obtain accurate results in a short time, which advantage eliminates unnecessary milling during die production and facilitates its production on a just-in-time basis according to customers' expectations and forecasts for vehicle demand. This paper presents an innovative compensation method for both forming and trimming die for the construction of vehicle parts manufactured by a transfer press. This method allows one to optimize the accuracy of compensation, consequently reducing springback in a more exact way than currently used methods, which account only for the influence of trimming on springback without generating compensated surfaces for the trimming die and the next forming operation. Moreover, there is a possibility to include the positioning effect during multioperation forming because of the huge impact of results on separate operations. When the positioning is not considered between operations there are problems with a proper shape even if the final part has the correct geometry. These problems generate some additional costs during the die production, which can be avoided by using the multioperation compensation. [ABSTRACT FROM AUTHOR]

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FlexRay is designed to support highly sophisticated interaction among electronic component units in modern automobiles. This protocol supports high data rates, up to 10 Mbit/s, and is a hybrid protocol which divides the time into two segments; static segment and dynamic segment. In static segment the time-triggered messages and in dynamic segment event-triggered messages are scheduled. This paper addresses message scheduling subject to precedence constraints in static segment of FlexRay. Our objective is to obtain optimum and sub-optimum scheduling solutions with respect to minimizing the number of used slots, and subject to the FlexRay specifications. We formulate the optimization problem using Integer Linear Programming, and we present a greedy heuristic which helps to reduce the search space of our optimization and achieves sub-optimal solutions more quickly. Our experiments on a prototypical application from a major automotive OEM demonstrate the efficiency of our proposed approaches. [ABSTRACT FROM AUTHOR]

The aim of this paper is to analyze efficient message relay methods in vehicular ad hoc networks (VANETs). Safety applications installed in vehicles aim to send a warning message to all reachable network vehicles as soon as possible. There are several broadcast methods for disseminating messages. We implement each broadcast method and compare methods. We evaluate the reliability and performance of our distance based priority broadcast method for VANETs environment on a highway simulation. This analysis allows us to study the impact of vehicle density and of multi hop forwarding. The proposed method can stably spread the messages in high density vehicular networks. Furthermore, we can con-firm only 1.8 %, the percentage of forwarded packets by the simulation results. [ABSTRACT FROM AUTHOR]

This paper deals with the evaluation of the interaction between a safety barrier and a variable message sign (VMS) that is placed very close to the carriageways in order to reduce the length of the arm above the carriageways. The two issues addressed are the structural response of the VMS, in order to ensure that the structure will not fail under the impact of a heavy goods vehicle (HGV), and the effects of the secondary impact that occurs when the barrier or the vehicle hits the VMS structure. These issues have been analysed both in terms of overall performance of the barrier and of the resulting effects on the HGV itself. As a result, the minimum distance between the front of the barrier and the VMS support structure that will enable to have a performance fully compatible with the requirements of EN1317-2:2010 has been defined for a specific barrier/VMS system. [ABSTRACT FROM AUTHOR]

Purpose -- The purpose of this paper is to examine how firms with multimarket contacts in both product and geographic markets make foreign direct investments (FDI) location choices and to advance the understanding about how managers with cognitive limits cope with opportunities to take the advantage of mutual forbearance in two types of markets. Design/methodology/approach -- Drawing upon the literatures on multimarket contact and decision making, the authors develop original hypotheses on how multimarket contacts in two types of markets influence firms' choice of destination for foreign investments. The authors test the hypotheses using longitudinal archival data on foreign market entries of Japanese auto parts makers. Findings -- The authors find that when choosing FDI locations, firms reduce the cognitive burdens of coping with multimarket contacts in the two types of markets by focussing exclusively on what is perceived as relevant to the decision at hand. The authors also find that this propensity is particularly significant for large firms, whereas small firms use different decision rules and avoid entering markets with the greater degree of multimarket contact with prior entrants, whether in product or national market. Practical implications -- Although heuristics simplify competitive environments and reduce managers' cognitive burdens, such a cost-saving orientation could increase the risk associated with international entry that may end in severe counterattacks from prior entrants, wasteful foreign investments, and substantial entry failures. Originality/value -- This study contributes to the literature by adopting multimarket contact theory to foreign market entry, jointly analyzing two types of multimarket contacts, testing three alternative hypotheses about how boundedly rational managers cope with multimarket contacts in two markets, and demonstrating that managers focus on multimarket contacts only in one type of markets when making entry decisions. [ABSTRACT FROM AUTHOR]

In the present work a comprehensive study of turbocharger heat transfer phenomena is discussed, showing their relevance compared to gas enthalpy variations through the turbomachinery. The study provides an experimental methodology to consider the different heat fluxes in the turbocharger and modeling them by means of a lumped capacitance heat transfer model (HTM). The input data required for the model are obtained experimentally by a proper combination of both steady and transient tests. These tests are performed in different test benches, in which incompressible fluids (oil) and compressible fluids (gas) are used in a given sequence. The experimental data allows developing heat transfer correlations for the different turbocharger elements. These correlations take into account all the possible heat fluxes, discriminating between internal and external heat transfer. In order to analyze the relative importance of heat transfer phenomena in the predictability of the turbocharger performance and the different related variables; model results, in hot and cold conditions, have been compared with those provided by the standard technique, consisting on using look up maps (LUM) of the turbocharger. The analysis of these results evidences the highly diabatic operative areas of the turbocharger and it provides clearly ground rules for using hot or cold turbocharger maps. In addition, paper discussion advises about using or not a HTM, depending on the turbocharger variables and the operative conditions that one desires to predict. Paper concludes that an accurate prediction of gas temperatures at turbine and compressor outlet and of fluid temperatures at water and oil ports outlet is not always possible without considering heat transfer phenomena in the turbocharger. [ABSTRACT FROM AUTHOR]

The collaboration between industry and higher education was materialized in organizing a facultative course for introduction in automotive electronics for the students of the Faculty of Electrical Engineering and Computer Science of Brasov. The novelty of this specialized course was that it addressed all the students from all the programmes of study from the Faculty and from all years of study. This paper presents the didactic and organizational challenges raised by this course with large audience. The feedback from students has analysed and conclusions drawn in order to improve the curricula of Programmes of study. [ABSTRACT FROM AUTHOR]