Criteria

Text:
Affiliation:
Display:

Results

Viewing 1 to 30 of 238
2015-04-14
Technical Paper
2015-01-1648
Hendrik Golzke, Heiko Holler, Wolfgang Friedrich, Philippe Leick, Ulrich Schoenauer, Andreas Dreizler
The spatial distribution of internal exhaust gas recirculation (EGR) is evaluated in an optically accessible direct injection spark ignition engine using near infrared laser absorption to visualize the distribution of the H2O molecule. The obtained overall internal exhaust gas recirculation compares well to gas-exchange cycle calculations and the spatial distributions are consistent with those measured with inverse LIF. The experimental procedures described in this report are designed to be simple and rapidly implemented without the need to resort to unusual optical components. The necessary spectral data of the selected absorption line is obtained from the HITEMP database and is validated with prior experiments carried out in a reference cell. Laser speckle in the images is effectively reduced using a ballistic diffuser.
2015-04-14
Technical Paper
2015-01-1715
Farouq Meddahi, Alain Charlet, Yann Chamaillard, Christian Fleck
Compressor models play a major role as they define the boost pressure in the intake manifold. These models have to be suitable for real-time applications such as control and diagnosis and for that; they need to be both accurate and computationally inexpensive. However, the models available in the literature usually fulfil only one of these two competing requirements. On the one hand, physics-based models are often too complex to be evaluated on line. On the other hand, data-based models generally suffer insufficient inter- and extrapolation features. To combine the merits of these two types of models, this work presents an extended approach to compressor modelling with respect to thermo- and aerodynamic losses. In particular, the model developed by Martin et al. [1] is augmented to explicitly incorporate friction, incidence and transfer losses.
2015-04-14
Journal Article
2015-01-1081
Axel Maier, Ulrike Klaus, Andreas Dreizler, Hermann Rottengruber
The fuel-independent particulate emissions of a direct injection gasoline engine were investigated. This was done by running the engine with reference gasoline at four different loads and then switching to hydrogen or methane port fuel operation and comparing the resulting particulate emissions and their size distribution. Differences in the combustion characteristics of hydrogen and gasoline were accounted for by diluting the inlet air with nitrogen and matching the pressure or heat release traces to those of gasoline operation. Methane operation is expected to generate particulate emissions lower by several orders of magnitude compared to gasoline and hydrogen does not contribute to carbon soot formation because of the lack of carbon atoms in the molecule. Thus, any remaining particulate emissions at hydrogen gas operation must arise from non fuel related sources, e.g. from lubrication oil, metal abrasion or inlet air.
2015-04-14
Journal Article
2015-01-1209
Zhengyu Liu, Thomas Winter, Michael Schier
The capability of heat dissipation in electric machine has great influence on its output performance. Under high output rating the temperature in the machine can raise rapidly due to losses generated in components. To ensure the lifetime and prevent machine failure, power output must be limited as soon as the temperature reaches a certain critical level. The electric machine continuous power density is restricted by this thermal effect. To increase power density and reduce machine size, studies on machine cooling have been intensively conducted over the last decades. This paper presents the development of a novel direct coil cooling approach which can enable high performance for electric traction motor, and in further significantly reduce motor losses. The proposed approach focuses on bypassing critical thermal resistances in motor by cooling coils directly in the stator slots with oil flows. In this approach the machine stator slots are sealed to air gap after the coils are mounted.
2015-04-14
Technical Paper
2015-01-1224
Ipek Sarac, Andreas Wagner, Uta Fischer, Rainer Schnurr
Challenges such as more stringent emission regulations and growing customer expectations for reduced real-life fuel consumption lead to an increase in percentage of hybrid electric vehicles (HEV) and ever stronger electrification of power train. Optimal energy consumption management for HEV requires a priori knowledge of route characteristics. By incorporating an in-vehicle navigation unit, partial route information such as slope, speed limit and curvature can be obtained and used to improve fuel consumption. Recently, several studies investigated planning of a near optimal driving strategy based on navigation information (e.g. Connected energy-based power train control for various hybrid vehicle topologies, Radke et al). By restricting combustion engine operation, HEV introduces new challenges to On-Board Diagnosis (OBD) functions which monitor emission-related power train components. Typically, an OBD function is associated with a condition which must hold throughout its execution.
2015-04-14
Technical Paper
2015-01-0385
Fabian Köpple, Paul Jochmann, Alexander Hettinger, Andreas Kufferath, Michael Bargende
The emission of particulate matter from future gasoline direct-injection (GDI) engines has to be optimized, to comply with more stringent emission standards such as EU6. Therefore, the mechanisms responsible for the formation of particles have to be analyzed in detail. From earlier investigations it is well-known that the deposition of liquid fuel wall films in the combustion chamber is a significant source of particle formation in GDI engines. Capturing the detailed dynamics of the deposited liquid fuel is therefore a key feature for the correct prediction of soot generated in a GDI engine. In a previous study particularly the wall surface temperature and the temperature drop due to the interaction with liquid fuel spray were identified as important parameters influencing the spray-wall interaction and thus the wall film formation (cf. SAE 2013-01-1089).
2015-04-14
Technical Paper
2015-01-0571
Andreas Teibinger, Christian Mayer, Ernö Dux, Gian Antonio D’Addetta, Peter Luttenberger, Jac Wismans, Rémy Willinger
In the next 20 years the number of small and light-weight full electric vehicles will substantially increase especially in urban areas. These Small Electric Vehicles (SEVs) show distinctive design differences compared to traditional vehicles (e.g. vertical windscreens, outstanding wheels). Thus the consequences of impacts of SEVs with vulnerable road users (VRUs) and other (mostly heavier) vehicles will be different from traditional collisions. These fundamental changes are not adequately addressed by current vehicle safety evaluation methods and regulations. Furthermore, no assessment concerning vehicle safety is defined for vehicles within European L7e class currently. Therefore the final objective of the EC co-financed project SafeEV is the development of a clear and practicable guideline for virtual testing of small electric vehicles. As a basis a virtual tool chain has to be defined for the realization of a guideline of virtual certification.
2015-04-14
Journal Article
2015-01-0168
Steffen Lampke, Simon Schliecker, Dirk Ziegenbein, Arne Hamann
The underlying theories of, both, control engineering and real-time systems engineering, assume idealized system abstractions that mutually neglect central aspects of the other discipline. Control engineering theory, on the one hand, usually assumes jitter free sampling and insignificant (constant) input-output latencies disregarding complex real-world timing effects. Real-time engineering theory, on the other hand, uses abstract performance and resource models that neglect the functional behavior, and derives worst-case situations that have little expressiveness for control functionalities in automotive systems. As a consequence, there is a lot of potential for a systematic co-engineering between both disciplines, increasing design efficiency and confidence. We have taken a standard control-engineering tool (Simulink) and combined it with state-of-the-art real-time system design and analysis tools (SymTA/S and TraceAnalyzer from Symtavision).
2015-04-14
Journal Article
2015-01-0196
Varun M. Navale, Kyle Williams, Athanassios Lagospiris, Michael Schaffert, Markus-Alexander Schweiker
This paper will present an overview of the evolution & revolution of automotive E/E architectures and how we at Bosch, envision the technology in the future. The paper will discuss bottlenecks for current E/E architectures and drivers for their evolution. Functionalities such as automated driving, connectivity and automotive security have gained increasing importance over the past few years. The importance of these functionalities will continue to grow as these cutting-edge technologies mature and market acceptance increases. Implementation of these functionalities in mainstream vehicles will demand a paradigm shift in E/E architectures with respect to communication networks, power networks, connectivity, safety and security. This paper will expound on these points at a system level.
2015-01-14
Technical Paper
2015-26-0172
Girikumar Kumaresh, Thomas Lich, Moennich Joerg
Abstract In the year of 2012 in India the total number of accidents with injuries is registered by Ministry of Road Transport and Highway with 490,383 out of which injured people are 509,667 and fatalities are 138,258 [1]. Nearly 17% of the fatalities are occupants of passenger cars which constitute the second highest contributor for fatal accidents in India [1]. In order to understand the root causes for car accidents in India, Bosch accident research carried out a study based on in-depth accidents collected in India. Apart from other accident contributing factors e.g. infrastructure the driver behaviour and his actions few milliseconds just prior to the crash is an extremely important and a key valuable data for the understanding of accident causation. Further on it supports also the development of modern automotive safety functions. Hence this research was undertaken to evaluate the benefit of the state-of-the art vehicle safety systems known as Antilock Braking System (ABS).
2015-01-14
Technical Paper
2015-26-0167
Thomas Lich, Girikumar Kumaresh, Joerg Moennich
Abstract Motorized two wheelers, also known as powered two wheelers (PTW) are the most common mode of transportation in India. Around one in four deaths that occurred on the roads in India in 2012 involved a motorcyclist, according to Ministry of Road Transport and Highways. This constitutes the highest contributor for fatal accidents in India [1]. The European Transport Safety Council (ETSC) analysis shows the risk of a motorcyclist having a fatal accident is 20 times greater than for a car driver travelling the same route [2]. An investigation conducted by Bosch looked at the accident database of Road Accident Sampling System for India (RASSI). This investigation revealed interesting facts about the Indian motorcycle accident situation, such as root causes of powered two wheeler collisions and riders behaviour including their braking patterns during the pre-crash phase of the accident.
2015-01-01
Journal Article
2014-01-9053
Tobias Breuninger, Jürgen Schmidt, Helmut Tschoeke, Martin Hese, Andreas Kufferath, Frank Altenschmidt
The spray-guided combustion process offers a high potential for fuel savings in gasoline engines in the part load range. In this connection, the injector and spark plug are arranged in close proximity to one another, as a result of which mixture formation is primarily shaped by the dynamics of the fuel spray. The mixture formation time is very short, so that at the time of ignition the velocity of flow is high and the fuel is still largely present in liquid form. The quality of mixture formation thus constitutes a key aspect of reliable ignition. In this article, the spray characteristics of an outward-opening piezo injector are examined using optical testing methods under pressure chamber conditions and the results obtained are correlated with ignition behaviour in-engine. The global spray formation is examined using high-speed visualisation methods, particularly with regard to cyclical fluctuations.
2014-11-11
Journal Article
2014-32-0076
Christian Steinbrecher, Bastian Reineke, Wolfgang Fischer, Henning Heikes, Thorsten Raatz
Abstract Equipping low cost two-wheelers with engine management systems (EMS) enables not only a reduction of emissions but also an improvement in fuel consumption and system robustness. These benefits are accompanied by initially higher system costs compared to carburetor systems. Therefore, intelligent software solutions are developed by Bosch, which enable a reduction of the necessary sensors for a port fuel injection system (PFI) and furthermore provide new possibilities for combustion control. One example for these intelligent software solutions is a model based evaluation of the engine speed. By use of the information contained in the engine speed signal, characteristic features like air charge, indicated mean effective pressure (imep) and combustion phasing are derivable. The present paper illustrates how these features could be used to reduce the system costs and to improve fuel consumption and system robustness.
2014-11-11
Journal Article
2014-32-0067
Henning Heikes, Christian Steinbrecher, Bastian Reineke, Jürgen Berkemer, Thorsten Raatz, Wolfgang Fischer
Abstract Cost reduction of engine management systems (EMS) for two-wheeler applications is the key to utilize their potentials compared to carburetor bikes regarding emissions, fuel economy and system robustness. In order to reduce the costs of a system with port fuel injection (PFI) Bosch is developing an EMS without a manifold air pressure (MAP) sensor. The pressure sensor is usually used to compensate for different influences on the air mass, which cannot be detected via the throttle position sensor (TPS) and mean engine speed. Such influences are different leakage rates of the throttle body and changing ambient conditions like air pressure. Bosch has shown in the past that a virtual sensor relying on model based evaluation of engine speed can be used for a detection of leakage air mass in idling to improve the pre-control of the air-fuel ratio. This provides a functionality which so far was only possible with an intake pressure sensor.
2014-04-01
Technical Paper
2014-01-0189
Bjoern Lumpp, Mouham Tanimou, Martin McMackin, Eva Bouillon, Erica Trapel, Micha Muenzenmay, Klaus Zimmermann
Abstract Current exhaust gas emission regulations can only be well adhered to through optimal interplay of combustion engine and exhaust gas after-treatment systems. Combining a modern diesel engine with several exhaust gas after-treatment components (DPF, catalytic converters) leads to extremely complex drive systems, with very complex and technically demanding control systems. Current engine ECUs (Electronic Control Unit) have hundreds of functions with thousands of parameters that can be adapted to keep the exhaust gas emissions within the given limits. Each of these functions has to be calibrated and tested in accordance with the rest of the ECU software. To date this task has been performed mostly on engine test benches or in Hardware-in-the-Loop (HiL) setups. In this paper, a Software-in-the-Loop (SiL) approach, consisting of an engine model and an exhaust gas treatment (EGT) model, coupled with software from a real diesel engine ECU, will be described in detail.
2014-04-01
Journal Article
2014-01-1446
Florian Schulz, Jürgen Schmidt, Andreas Kufferath, Wolfgang Samenfink
Due to the principle of direct injection, which is applied in modern homogeneously operated gasoline engines, there are various operation points with significant particulate emissions. The spray droplets contact the piston surface during the warm-up and early injections, in particular. The fuel wall films and the resulting delayed evaporation of the liquid fuel is one of the main sources of soot particles. It is therefore necessary to carry out investigations into the formation of wall film. The influence of the spray impact angle is of special interest, as this is a major difference between engines with side-mounted injectors and centrally positioned injectors. This paper describes an infrared thermography-based method, which we used to carry out a systematic study of fuel deposits on the walls of the combustion chamber. The boundary conditions of the test section were close to those of real GDI engines operated with homogeneous charge.
2014-04-01
Journal Article
2014-01-1447
Fabian Köpple, Dimitri Seboldt, Paul Jochmann, Alexander Hettinger, Andreas Kufferath, Michael Bargende
In order to comply with more and more stringent emission standards, like EU6 which will be mandatory starting in September 2014, GDI engines have to be further optimized particularly in regard of PN emissions. It is generally accepted that the deposition of liquid fuel wall films in the combustion chamber is a significant source of particulate formation in GDI engines. Particularly the wall surface temperature and the temperature drop due to the interaction with liquid fuel spray were identified as important parameters influencing the spray-wall interaction [1]. In order to quantify this temperature drop at combustion chamber surfaces, surface temperature measurements on the piston of a single-cylinder engine were conducted. Therefore, eight fast-response thermocouples were embedded 0.3 μm beneath the piston surface and the signals were transmitted from the moving piston to the data acquisition system via telemetry.
2013-10-15
Journal Article
2013-32-9037
Christian Steinbrecher, Bastian Reineke, Jurgen Berkemer, Henning Heikes, Wolfgang Fischer
Regarding the strongly growing two-wheeler market fuel economy, price and emission legislations are in focus of current development work. Fuel economy as well as emissions can be improved by introduction of engine management systems (EMS). In order to provide the benefits of an EMS for low cost motorcycles, efforts are being made at BOSCH to reduce the costs of a port fuel injection (PFI) system. The present paper describes a method of how to reduce the number of sensors of a PFI system by the use of sophisticated software functions based on high-resolution engine speed evaluation. In order to improve the performance of a system working without a MAP-sensor (manifold air pressure sensor) an air charge feature (ACFn) based on engine speed is introduced. It is shown by an experiment that ACFn allows to detect and adapt changes in manifold air pressure. Cross-influences on ACFn are analyzed by simulations and engine test bench measurements.
2013-10-15
Journal Article
2013-32-9125
Bernd Heinzmann, Simon Scholz, Pramod R, Prashanth Anantha
Fuel economy of two-wheelers is an important factor influencing the purchasing psychology of the consumer within the emerging markets. Additionally, air pollution being a major environmental topic, there is a rising concern about vehicle emissions, especially in the big cities and their metropolitan areas. Potentially, the relatively expensive engine management systems are providing more features and value in comparison to the carburettor counterpart. The combustion system analysis is carried out on a 125 cm3 motorcycle engine and the subsequent numerical simulation comparing the carburettor and the Electronic (Port) Fuel Injection which provides a basis to establish the fuel consumption benefit for the electronic injection systems [1].
2013-04-08
Technical Paper
2013-01-1730
Alexander Eichhorn, David Lejsek, Alexander Hettinger, Andreas Kufferath
To meet future CO₂ emissions limits and satisfy the bounds set by exhaust gas legislation reducing the engine displacement while maintaining the power output ("Downsizing") becomes of more and more importance in the SI engine development process. The total number of cylinders per engine has to be reduced to keep the thermodynamic disadvantages of a small combustion chamber layout as small as possible. Doing so new challenges arise concerning the mechanical design, the design of the combustion system concept as well as strategies maintaining a satisfying transient torque behavior. To address these challenges a turbocharged 2-cylinder SI engine was designed for research purposes by Weber Motor GmbH and Robert Bosch GmbH. The design process was described in detail in last year's paper SAE 2012-01-0832. Since the engine design is very modular it allows for several different engine layouts which can be examined and evaluated.
2013-04-08
Journal Article
2013-01-1089
Fabian Köpple, Paul Jochmann, Andreas Kufferath, Michael Bargende
Due to the EU6 emission standard that will be mandatory starting in September 2014 the particulate emissions of GDI engines come into the focus of development. For this reason, soot and the mechanisms responsible for the soot formation are of particular importance. A very significant source of particulate emissions from engines with gasoline direct injection is the wall film formation. Therefore, the analysis of soot emission sources in the CFD calculation requires a detailed description of the entire underlying model chain, with special emphasis on the spray-wall interaction and the wall film dynamics. The validation of the mentioned spray-wall interaction and wall film models is performed using basic experimental investigations, like the infrared-thermography and fluorescence based measurements conducted at the University of Magdeburg.
2013-04-08
Journal Article
2013-01-0891
Sumit Khadilkar, Ahmed Soliman, Peter Schuetzbach, Marko Kustic
Filtration of diesel and gasoline fuel in automotive applications is affected by many external and internal parameters, e.g. vibration, temperature, pressure, flow pulsation, and engine start-stop. Current test procedures for automotive fuel filters, proposed by most of the researchers and organizations including Society for Automotive Engineers (SAE) and International Organization for Standardization (ISO), do not apply the previously mentioned real-world-conditions. These operating conditions, which are typical for an automotive fueling system, have a significant effect on fuel filtration and need to be considered for the accurate assessment of the filter. This requires the development of improved testing procedures that will simulate the operating conditions in a fuel system as encountered in the real world.
2013-01-09
Technical Paper
2013-26-0022
Girikumar Kumaresh, Thomas Lich, Jorg Moennich, Andreas Georgi
The 2011 Report of Ministry of Road Transport and Highways, Government of India states that the total accidents with injuries is estimated about 497, 686 out of which the injuries are 511, 394 and fatalities are 142, 485, an average of one fatality per 3.5 [1]. Social losses on account of these crashes are estimated at over Rupees 100 000 Crores annually or 3% of our Gross Domestic Product (GDP) [2]. The irony is that these causalities are rising at 5.9 % annually. India accounts for 10% of the global road crash fatalities. Therefore traffic safety became very important in India. In order to understand the root causes of accidents data is needed in more detail which could be analyzed and points out the major issues to find solutions to stop this trend. Besides vehicle safety, infrastructure related issues and education skills can be derived out of accident data. Official statistics regarding accidents in India are available in national and state wise reports.
2012-10-23
Technical Paper
2012-32-0067
Frank Schuerg, A. Prashanth, Thorsten Raatz, Dani C, K. Manikandan, V Padmanabhan
Based on the fuel consumption analysis methods published on last year's SETC [1], we compared fuel economies of a typical 125cc production motorcycle equipped with either electronic (port) fuel injection (EFI/PFI) engine management system (EMS) or constant vacuum carburetor (Carb). In addition to earlier discussed PFI results, stationary engine map measurements of fuel consumption on an engine dynamometer (dyno) were conducted for the Carb engine. The powerful development tool of fuel consumption test cycle simulation uses these stationary engine dyno results to calculate fuel consumption of real transient vehicle operation. Here it was employed to assess economy of both fuel system configurations under different driving conditions. Besides the Indian Driving Cycle (IDC) and the World Motorcycle Test Cycle (WMTC), we investigated real world drive patterns typical for emerging markets in terms of a Bangalore urban cycle and a Malaysian suburban cycle.
2012-10-23
Technical Paper
2012-32-0052
Timo Jahn, Frank Schuerg, Stefan Kempf
Today, knock control is part of standard automotive engine management systems. The structure-borne noise of the knock sensor signal is evaluated in the electronic control unit (ECU). In case of knocking combustions the ignition angle is first retarded and then subsequently advanced again. The small-sized combustion chamber of small two-wheeler engines, uncritical compression ratios and strong enrichment decrease the knock tendency. Nevertheless, knock control can effectuate higher performance, lower fuel consumption, compliance with lower legally demanded emission limits, and the possibility of using different fuel qualities. The Knock-Intensity-Detector 2 (KID2) and the Bosch knock control tool chain, based on many years of experience gained on automotive engines, provides an efficient calibration method that can also be used for two-wheeler engines. The raw signal of the structure-borne noise is used for signal analysis and simulation of different filter settings.
2012-10-23
Technical Paper
2012-32-0044
Silke Seuling, Haris Hamedovic, Wolfgang Fischer, Frank Schuerg
In order to fulfil emission legislation and achieve good drivability of combustion-engine-powered vehicles, information about the air charge and feedback about the engine condition is necessary. In current systems, different sensors are used, e.g. the MAP (manifold air pressure) sensor and a lambda sensor. Aiming at reducing costs, efforts are being made to reduce the number of sensors while still retrieving the necessary information. Various engine speed based functions are state-of-the-art for automotive engines, e.g. for fuel-calibration, misfire-detection etc. Those functions evaluate the engine speed fluctuations during a working cycle induced by combustion. For multiple-cylinder engines, those influences are overlapping, therefore evaluation possibilities are limited. The work presented is based on the effect that at a single-cylinder engine, there is no overlap of combustion influences of various cylinders on the crankshaft.
2012-10-08
Technical Paper
2012-01-9007
Klaus Benninger, Uta Fischer, Cathy Lillie
The electrification of the powertrain, the diversity and the complexity of the more or less individual technical solutions which are preferred by different car manufacturers, create a steadily increasing challenge for the whole automotive industry. Missing standards and sales volumes still below the market expectations on the one hand, and the increasing interaction of the main powertrain domains (engine, transmission, e-drive) caused by upcoming cross domain functions on the other hand, lead to increasing development costs and non-optimal solutions concerning fuel economy improvement. Within the domain of engine management systems Bosch established in the mid-nineties the so called torque structure as the solution to a similar situation addressing the coordination of air management, fuel injection and ignition.
2012-04-16
Technical Paper
2012-01-1105
Tobias Nier, Andre Kulzer, Roland Karrelmeyer
The worldwide stricter emission legislation and growing demands for lower fuel consumption require for significant efforts to improve combustion efficiency while satisfying the emission quality demands. Homogeneous Charge Compression Ignition (HCCI) on gasoline engines provides a particularly promising and, at the same time, challenging approach, especially regarding the combustion mode switch between spark-ignited (SI) and gasoline HCCI mode and vice-versa. Naturally aspirated (n.a.) HCCI shows considerable potential, but the operation range is air breathing limited due to hot residuals required for auto-ignition and to slow down reaction kinetics. Therefore it is limited to part-load operation. Considering the future gasoline engine market with growing potentials identified on downsized gasoline engines, it is imperative to investigate the synergies and challenges of boosted HCCI.
2012-04-16
Technical Paper
2012-01-0198
Thorsten Huck, Andreas Rohatschek, Dieter Thoss, Stoyan Todorov
A new high-performance interchip interface, called Serial WireRing, is introduced. It combines technically mature and established methods, whereby Serial WireRing provides a simple, robust and very inexpensive solution to replace the Serial Peripheral Interface (SPI). Serial WireRing uses a daisy chain ring topology, realized by unidirectional point-to-point connections from device to device. Serial WireRing is realized by a simple “wire ring” with CMOS, LVDS, optical or any other suitable signaling, even mixed. Therefore it has a very low pin count. In order to minimize the latency each slave transmits the data that it receives with 1 bit delay only. In order to avoid clock/data skew, the serial data and clock are merged into one bitstream. A corresponding clock is extracted at each receiver by a clock and data recovery circuit, driven by a simple internal oscillator.
2012-04-16
Technical Paper
2012-01-0288
Alexander E. Schanz, Reinhold Hamann
“Safe Driving” is an essential world-wide automotive requirement. The demand for “Safe Driving” is particularly high in industrialized countries, but it is also growing in the fast-developing nations. However, the annual reduction of serious traffic injuries and fatalities is still too low and the target to halve the number of people killed in traffic in the European Union from 2001 to 2010 has not been met. Essential influences to close this gap include legislation, road traffic regulations and monitoring, technical improvement of vehicles including active and passive safety systems, the increase of the equipment rate for safety functions and the re-design of traffic infrastructure for safety reasons. During the last years several countries in Europe started to consider these aspects combined in an integrated and general traffic safety policy, i.e. “Vision Zero” in Sweden.
Viewing 1 to 30 of 238

Filter

  • Range:
    to:
  • Year: