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Viewing 1 to 30 of 16906
2015-09-29
Technical Paper
2015-01-2811
Tingjun Hu, Ho Teng, Xuwei Luo, Chun Lu, Jiankun Luo
When highly boosted, turbocharged gasoline direct injection (TGDI) engines can have torque curves comparable to those of light-duty (LD) diesel engines. Hence, applications of TGDI engines have been considered to be extended from passenger cars to LD vehicles, such as Ford F150 and E150. Most modern TGDI engines employ homogeneous mixture combustion with an injection pressure  150 bar typically. Under this combustion mode, two challenges having to be faced in the engine development are: 1) fuel dilution of the crankcase oil due to interactions of fuel sprays with the cylinder wall as a result of spray impingement on the cylinder wall or on the piston top when the fuel demand is high or fuel condensation during the warmup phase; 2) low-speed pre-ignition (LSPI) at high loads and low speeds, which often leads to a severe knock combustion known as the super knock. It is widely believed that LSPI is triggered by self ignition of oil particles entered the engine cylinder.
2015-09-29
Technical Paper
2015-01-2876
Shankar Patil, P Mahesh, Krishnan Sadagopan, Gokhul SA
In a tropical conditions , over a period of several months using 12 Nos. of New Generation 9-15T Intermediate Commercial Vehicles built with 4-Cyl 120HP BS3 Diesel engines run at regular interval from zero to 60000 Km. Field run data composed and analyzed with Intended Duty cycle for engine oil drain life estimation . The ICV trucks with sump capacity 0.083- 0.104 Liter/hp and SAE 15W40 viscosity of oil meeting API CH-4, API CI-4+ from group –I and Group-II base stocks are considered. The engine wear is more a function of silica concentration, load factor and age than the API category of oil. Oil drain interval is found proportional to the sump volume for the same stress on oil. Iron concentration and kinematic viscosity decide useful oil life with respect to the limits fixed by the engine manufacturer. In tropical conditions, field trials are carried out on 10T payload vehicles at higher temperature, humidity, dust levels and load factor than the other hemisphere conditions.
2015-09-29
Technical Paper
2015-01-2843
Xu Kuang, Jianqiang Wang, Keqiang Li
Transport vehicles consume a large amount of fuel with low efficiency, which is significantly affected by driver behavior. An assessment system of eco-driving pattern for buses could identify the deficiencies of driver operation as well as assist transportation enterprises in driver management. This paper proposes an assessment method regarding drivers’ economic efficiency, considering driving conditions obtained from the GPS data and an online map database. To this end, assessment indexes are extracted from driving economy theories and ranked according to their effect on fuel consumption, derived from a database of 135 buses using multiple regression. The 12 selected characteristic indexes represent four aspects of driving behavior including speed, acceleration, engine and accessories control. A layered structure of assessment indexes is developed with application of AHP, and the weight of each index is estimated.
2015-09-29
Technical Paper
2015-01-2772
Amy Kopin, Steven Musselman
For decades, the heavy-duty (“HD”) commercial vehicle industry has focused on improving fuel economy in order to lower the total operating cost for its customers. Most recently, there has been a revolution in the HD industry which means no longer do OEMs focus on discreet components but instead look at the entire vehicle and operations to improve efficiency; it is likely future gains will come through an integrated approach to optimizing the entire vehicle. The path forward is not sufficiently clear looking into the next decade, nor will one solution work for all manufacturers or all vehicle applications. Therefore, the regulations must be sufficiently adaptive. This paper explores further the ideas presented in other SAE papers that have focused on regulation of engine-only emissions as an approach for the HD commercial vehicle market.
2015-09-29
Technical Paper
2015-01-2778
Joe Steiber, Coralie Cooper, John Whitefoot, James MacIsaac
A study was funded by NHTSA to help inform the Phase 2 GHG and Fuel Efficiency Standards for Medium- and Heavy-Duty Engines and Vehicles. The goal of the study was to review technologies that could be used by Class 2b through Class 8 trucks to comply with possible future regulatory requirements, and determine their potential performance. The vehicles and engines selected for the study had extensive experimental data available from earlier work. The four trucks were a Kenworth T700 tractor, a Kenworth T270 box delivery truck, a Ford F-650 tow truck, and a Ram 2500 / 3500 pickup. For the long haul tractor, a Detroit DD15 engine was used. The pickup and medium-duty trucks used two different ratings of the Cummins ISB diesel, as well as a 6.2 liter naturally-aspirated gasoline V-8 and a turbocharged, direct-injected 3.5 liter gasoline V-6. All engine simulations were performed with GT-POWER.
2015-09-29
Technical Paper
2015-01-2798
Madhushankar Palanisamy, Jeffrey Lorch, Russell J. Truemner, Brian Baldwin
Modern diesel systems have come to rely on fuel systems with the capacity for high injection pressures. The benefits of such high pressures include improved tolerance for EGR, reduced emissions and improved performance. Current production fuel systems have typical capacities to 2500bar, when a decade ago 1800 bar was a typical limit. Following this trend, the current investigation investigates the effect of injection pressures up to 3000 bar on a 1.5L single cylinder research engine. The injector nozzles tested include two variations in flow rate, the number of holes, and spray cone angle. In addition to fuel injection pressure, the effects of intake swirl, excess-air ratio, EGR, and injection timing are evaluated at speed and load points representative of A100, B100, and C100 test conditions of the U.S. EPA on-highway 13 Mode test cycle.
2015-09-29
Technical Paper
2015-01-2850
John Kargul, Andrew Moskalik, Kevin Newman, Daniel Barba, Jeffra Rockwell
The United States Environmental Protection Agency’s (EPA’s) National Center for Advanced Technology (NCAT), located at its National Vehicle and Fuel Emissions Laboratory in Ann Arbor, Michigan, has been known for its development and demonstration of numerous low-greenhouse gas and fuel efficient series hydraulic hybrid drivetrain technologies and their application in commercial vehicles. Advances in these very fuel efficient hydraulic hybrid vehicle technologies have led the industry to begin manufacturing these exciting new technologies for both the commercial truck and non-road equipment markets, with development activities continuing in other markets including light-duty vehicles. The commercial emergence of these very low-greenhouse gas emitting hybrids led EPA to decide that the time had come to wind down its leadership role in developing and demonstrating these very fuel efficient technologies.
2015-09-29
Technical Paper
2015-01-2853
Enrique Busquets, Monika Ivantysynova
Over the last decade, a number of hybrid architectures have been proposed with the main goal of minimizing energy consumption of off-highway vehicles. One of the architecture subsets which has progressively gained attention is hydraulic hybrids for earth-moving equipment. Among these architectures, hydraulic hybrids with secondary-controlled drives have proven to be a reliable, implementable, and highly efficient alternative with the potential for up to 50% engine downsizing when applied to excavator truck-loading cycles. Multi-input multi-output (MIMO) robust linear control strategies have been developed by the authors’ group with notorious improvements on the control of the state of charge of the high pressure accumulator. Nonetheless, the challenge remains to improve the actuator position and velocity tracking.
2015-09-29
Technical Paper
2015-01-2893
Ashok Patidar, Ankur Bansal, Umashanker Gupta
Market driven competition in global trade and urgency for controlling the atmospheric air pollution are the twin forces, which have urged Indian automobile industries to catch up with the international emission norms. Improvement in the fuel efficiency of the vehicles is one way to bind to these stringent norms. It is experimentally proven that almost 45% of the engine power is being consumed to overcome the drag resistance and around 40% to overcome the tire rolling resistance of the vehicle. This as evidence provides a huge scope to investigate the influence of aerodynamic drag and rolling resistances on the fuel consumption of a commercial vehicle. The present work is a numerical study on the influence of aerodynamic drag resistance on the fuel consumption of a commercial passenger bus. The commercial CFD code FLUENT is used as a solver to estimate the drag coefficient of the bus. Around 35% improvement in the drag coefficient is achieved by CFD driven changes in the bus design.
2015-09-29
Technical Paper
2015-01-2812
Lijuan Wang, Adam Duran, Jeffrey Gonder, Kenneth Kelly
In this paper the authors present multiple methods for predicting heavy/medium-duty (HD/MD) vehicle fuel consumption (FC) based on FC data gathered from chassis dynamometer cycles. In addition to presenting a range of methods for predicting FC, the authors also present the results of model training using chassis dynamometer data as well as the results of testing done using real world drive cycle (RWDC) data to evaluate the accuracy of each method. A linear model, a multivariate adaptive regression splines (MARS) model and a black box neural network model were developed using chassis test results in an effort to predict FC for RWDCs based on drive cycle metrics such as road grade, vehicle speed, acceleration rate, inertial power, and standard deviation of driving speed.
2015-09-29
Technical Paper
2015-01-2817
Matthew Goertz PhD, Lloyd Tull, Davis Moravec PhD
The winter of 2013-2014 provided an opportunity to operate off-road vehicles in cold weather for extended time as part of a vehicle/tier 4 diesel engine validation program. An unexpected area of study was the performance of high efficiency, on engine, fuel filters during continuous vehicle operation in cold weather with cold fuel. During the program, we observed unexpected, premature fuel filter plugging as indicated by an increase in pressure drop across the filter while in service. Additional field testing and laboratory testing was completed to further understand the cause of filter plugging. In some cases, laboratory testing of returned plugged filters did not reveal a high pressure drop across the filter and visual examination did not provide additional insight.
2015-09-29
Technical Paper
2015-01-2821
Xuan Feng, Mahesh Madurai Kumar, Long-Kung Hwang, Travis Anderson, Justin Blomenberg
Diesel-electric powertrains are used by a variety of industrial machines and marine vessels. In such a powertrain configuration, a diesel engine coupled with an electrical generator provides power to electric motors that drive the application. Fuel consumption of such applications account for a majority of the operating cost, and even a small reduction in the percentage of fuel used can translate into considerable cost savings. Hence, methodologies and technologies that can deliver fuel economy improvements are a central focal point for many industries like mining haul trucks, locomotives and marine vessels. This paper describes an ALD methodology applicable to such machines. The case of a mining haul truck application has been used for purposes of illustration. A Matlab/Simulink based model has been developed at Cummins to represent a generic machine with diesel electric powertrain.
2015-09-29
Technical Paper
2015-01-2816
Andrei Radulescu, Leighton Roberts, Eric Yankovic
Cylinder deactivation (CDA) is an effective method to adjust the engine displacement, for maximum output and improving fuel economy, by adjusting the numbers of active cylinders in the combustion engines. Switching Roller Finger Followers (SRFF) are an economic solution for CDA that minimize changes and preserve the overall width, height or length of Dual Overhead Cam (DOHC) engines. The CDA SRFF provides the flexibility of transferring or suppressing the camshaft movement to the valves influencing the engine performance and fuel economy by reducing the pumping losses. This paper addresses the performance and durability of the CDA SRFF system in meeting the reliability for modern automobile engines. Extensive tests were conducted to demonstrate the dynamic stability at high engine speeds, and the system capacity of switching between high and low engine displacement within one camshaft revolution.
2015-09-29
Technical Paper
2015-01-2819
Vasu Kumar, Dhruv Gupta, Mohd Waqar Naseer Siddiquee, Aksh Nagpal, Naveen Kumar
To comply with the future stringent emission standards, innovative diesel engine technology, exhaust gas after-treatment, and clean alternative fuels are required. On the other hand, the growing energy demand and limited petroleum resources in the world have guided researchers towards the use of clean alternative fuels like alcohols for their better tendency to decrease the engine emissions. The use of oxygenated fuels like alcohols showed tendency to decrease internal combustion engine emissions. The use of alcohols as a blending agent in diesel fuel is rising, because of its benefits like enrichment of oxygen, premixed low temperature combustion and enhancement of the diffusive combustion phase. Several researchers have investigated the relationship between LTC operational range and cetane number. In a light-duty diesel engine working at high loads, a low-cetane fuel allowed a homogeneous lean mixture with improved NOx and smoke emissions joint to a good thermal efficiency.
2015-09-29
Technical Paper
2015-01-2881
Dhruv Gupta, Vasu Kumar, Soumya Roy, Naveen Kumar
The danger posed by climate change and the striving for security of energy supply are issues high on the political agenda these days. Governments are putting strategic plans in motion to decrease primary energy use, take carbon out of fuels and facilitate modal shifts. Man’s energy requirements are touching astronomical heights. The natural resources of the Earth can no longer cope with it as their rate of consumption far outruns their rate of regeneration. The automotive sector is without a doubt a chief contributor to this mayhem as fossil fuel resources are fast depleting. The harmful emissions from vehicles using these fuels are destroying our forests and contaminating our water bodies and even the air that we breathe. The need of the hour is to look not only for new alternative energy resources but also clean energy resources. Hydrogen is expected to be one of the most important fuels in the near future to meet the stringent emission norms.
2015-09-29
Technical Paper
2015-01-2809
Sajit Pillai, Julian LoRusso, Matthew Van Benschoten
Cylinder deactivation was evaluated both analytically and experimentally on a diesel engine. This paper evaluates cylinder deactivation for potential benefits in fuel consumption and exhaust thermal management for improved after treatment system performance. An analytical study was conducted using GT-Power to evaluate potential benefits of deactivation. The model was validated at low-load, steady-state points by optimizing Exhaust Gas Recirculation (EGR) and Variable Geometry Turbocharger (VGT) to maintain similar or acceptable emission levels between base and deactivated modes of operation. The results demonstrated significant improvements in Brake Specific Fuel Consumption (BSFC) for low and part load operating points along with higher exhaust gas temperatures. The analytical results offered enough potential benefit to warrant an experimental investigation. To validate the analytical results, an experimental evaluation was performed.
2015-09-29
Technical Paper
2015-01-2813
Philip Zoldak, Jeffrey Naber
The increased availability of natural gas (NG) in the United States (US) and its relatively low cost compared to diesel fuel has heightened interest in the conversion of medium duty (MD) and heavy duty (HD) engines to NG fueled combustion systems. The aim is to realize fuel cost savings and reduce harmful emissions, while maintaining durability. This is a potential path to help the US reduce dependence on crude oil. Traditionally, port-fuel injection (PFI) or premixed NG spark-ignited (SI) combustion systems have been used for MD and HD engines with widespread use in the US and Europe; however, this technology exhibits poor cycle efficiency and is load limited due to knock phenomenon. Direct Injection of NG during the compression stroke promises to deliver improved thermal efficiency by avoiding excessive premixing and extending the lean limits which helps to extend the knock limit.
2015-09-29
Technical Paper
2015-01-2797
Meichun Peng, Yue Zheng, Xiaoyan Jiang, Jiahao Wang
This paper studies the characteristics of fuel consumption and emission of city transit buses,and analyzes the fuel conservation and emission reduction rate of LPG-HEV buses relative to LPG bases. The run speed, fuel consumption and the exhaust emission,etc. of 3 LPG-HEV buses and 2 LPG buses were tested by a portable emission measurement system (PEMS) under real driving world of city transit buses at Guangzhou in China. The test data was analyzed, and the test results were compared between LPG-HEV buses and LPG buses. The study results show the buses run below than 35 km/h and in acceleration region of -0.5~0.5 m/s2 mainly, the average speed is 18 km/h. The average fuel consumption of LPG-HEV buses is 51.02 l/100km with a drop of 6.23% compared with LPG buses, and the fuel saving appears below than 25 km/h, the lower the speed, the more obvious the effect of fuel saving.
2015-09-29
Technical Paper
2015-01-2830
Shashank Agarwal, Michael Olson, Tim Meehan, Nachiket Wadwankar
Fuel economy is one of the major challenges for both on and off-road vehicles. Inefficient engine operation and loss of kinetic energy in the form of heat during braking are two of the major sources of wasted fuel energy. Rising energy costs, stringent emission norms and increased environmental awareness demand efficient drivetrain designs for the next generation of vehicles. This paper analyses three different types of powertrain concepts for efficient operation of a forklift truck. Starting from a conventional torque converter transmission, hydrostatic transmission and a hydraulic hybrid system (Eaton architecture) are compared for their performance. Eaton hydraulic hybrid system is seen to perform much better compared to other two configurations. Improved performance is attributed to efficient engine operation and regeneration of vehicle kinetic energy during braking.
2015-09-29
Technical Paper
2015-01-2807
Katharina Eichler, Yousef Jeihouni, Carl Ritterskamp
In the near future engine emitted carbon dioxides (CO2) are being limited for all vehicle categories with respect to the Green House Gases (GHG) norms. To cope with this challenge, new concepts need to be developed. For this reason waste heat recovery is a promising research field. For commercial vehicles the first phase of CO2 emission legislation will be introduced in the USA in 2014 and will be further tightened towards 2030. Beside the US, CO2 emission legislation for commercial engines will also be introduced in Europe in the near future. The demanded CO2 reduction calls for a better fuel economy which is also of interest for the end user, specifically for the owners of heavy duty diesel vehicles with high mileages. To meet these future legislation objectives, a waste heat recovery system is a beneficial solution to recover the wasted energies from different heat sources in the engine.
2015-09-29
Technical Paper
2015-01-2808
Philip Zoldak, Jeffrey Naber
In recent years, natural gas has been considered a replacement for diesel fuel in large bore engines, due to its low cost, high heating value and widespread availability. Stoichiometric premixed spark-ignition (SI), defined as port-fuel injection (PFI) of natural gas (NG) followed by SI close to top dead center (TDC), has traditionally been used as the main fuel delivery and combustion method for light and medium duty engines. However, premixed SI of NG results in inefficiencies in the intake process and combustion that is knock limited as boost and load are increased. Traditionally, high knock is addressed by spark timing retard. Spark timing retard can lead to misfires and low brake mean effective pressures. Thus premixed SI has limited low load use in heavy duty where compression ignition of diesel fuel remains dominant.
2015-09-29
Technical Paper
2015-01-2874
Marius-Dorin Surcel, Adime Kofi Bonsi
Lift axles increase the load capacity of a vehicle, allowing it to carry the extra load without the need for multiple vehicles, hence reducing operational costs. Furthermore, additional axles help to distribute the truck’s load across the road surface, reducing the chances of damage to the infrastructure. Lift axles can be raised when the vehicle has lighter load to save fuel and reduce wear and tear to the tires and axles. They can be deployed to improve traction especially in icy off-road applications. The main objective of this project was to assess the fuel-saving potential of lifting axles on unloaded semi-trailers. Part of the mandate was to identify and analyze regulations of various jurisdictions with respect to lift/loadable axles and studies leading to the setting up of these regulations. The SAE Fuel Consumption Test Procedures Type II (J1321) was used for fuel consumption track test evaluations.
2015-09-29
Technical Paper
2015-01-2894
Marius-Dorin Surcel, Mithun Shetty
The performance of several aerodynamic technologies and approaches, such as trailer skirts, trailer boat tails, gap deflectors and gap reduction, was evaluated using track testing, model wind tunnel testing, and CFD simulation, in order to assess the influence of the design, position and combination of various aerodynamic devices. Scale model wind tunnel tests were conducted to have the best direct performance comparisons between several possible configurations. The track test procedure followed the SAE J1321 SAE Fuel Consumption Test Procedure - Type II. The wind tunnel tests were conducted on a 1/8 scale model of a tractor in combination with a 53-foot semi-trailer. The tests consisted of two phases: setting the initial baseline, and component testing of various configurations.
2015-09-29
Technical Paper
2015-01-2875
Olof Lindgärde, Lei Feng, Anders Tenstam, Mikael Soderman PhD
CONVENIENT is a project where prediction and integrated control are applied on several subsystems with electrified actuators. A primary project goal is to develop a model-based optimal controller that uses predictive information in order to minimize fuel consumption. Another goal is to develop a control structure that both supports optimality and modularity since there is a need of adapting the controller to various truck configurations. A high-level controller denoted “Predictive Energy Buffer Control” controls several energy buffers in an integrated and optimal way using model predictive control. Several buffers are considered, such as the cooling system, the battery, and the vehicle kinetic energy. Controlling the vehicle kinetic energy means that when in cruise control mode the vehicle speed is varied with respect to the set speed in a fuel efficient way. Another focus is the communication between the driver and the control system.
2015-09-29
Technical Paper
2015-01-2852
Daniel Ribeiro, Rodrigo Chaves, Rogerio Curty Dias, Gian Marques
In order to evaluate the opportunities to use hybrid concepts for heavy commercial vehicles for emerging markets, MAN Latin America has developed a VW refuse truck with 23t GVW using the hybrid hydraulic technology. In site vehicle tests measurements has indicated a fuel savings up to 25%, which means a reduction around 4.08 liters of diesel/hour or 20 tones CO2/year . Thus, a collaborative cooperation with Rio de Janeiro Sanitation Department (Comlurb) was set for a truck evaluation on a real operation. This 03-month evaluation used one VW 17.280 6x2 hybrid hydraulic refuse truck and other VW refuse truck similar standard diesel. A random dispatch system ensures the vehicles are used in a similar manner. Global positioning system logging, fueling, and maintenance records are used to evaluate the performance of this hybrid hydraulic refuse truck.
2015-09-29
Technical Paper
2015-01-2885
Nicholas Schaut, Raja Sengupta
As part of the United States Department of Energy’s SuperTruck program, Volvo Trucks and its partners were tasked with demonstrating 50% improvement in overall freight efficiency for a tractor-trailer, relative to a best in class 2009 model year truck. This necessitated that significant gains be made in reducing aerodynamic drag of the tractor-trailer system, so trailer side skirts and a trailer boat tail were employed. A Lattice-Boltzmann based simulation method was used in conjunction with a Kriging Response Surface optimization process in order to efficiently describe a design space of seven independent parameters relating to boat tail and side skirt dimensions, and to find an optimal configuration. In two separate phases of optimization conducted with different constraints, the most influential parameters are identified in achieving significant aerodynamic drag reduction relative to a base configuration. The result was corroborated by on-road fuel economy testing.
2015-09-29
Technical Paper
2015-01-2882
Abhishek Shah, Karthick Rr, Sanjay Phegade, Aravindan V, Sappani Murugesh
Today the entire world is facing many serious problems namely population explosion, pollution and increasing fuel Prices. Increasing fuel prices is due to the depletion of non-renewable sources of energy, which will adversely affect automotive industry in very near future. Thus it's our responsibility to optimize vehicle fuel economy as much as possible and reduce the CO2 released by the vehicle. This paper focuses on optimizing the electrical energy consumption of vehicle. By introduction three concepts. 1) Innovative speed control logic for radiator & condenser fan motor according to air flow through radiator. 2) Introducing regeneration of energy from radiator and condenser fan motor while free running and deceleration of vehicle. 3) Using AC asynchronous motors (generation and motoring action) in radiator, condenser and blower motors.
2015-09-15
Technical Paper
2015-01-2410
Fei Gao, Serhiy Bozhko, Greg Asher, Patrick Wheeler
DC electrical power system (EPS) for the future more electric aircraft (MEA) is promising due to several advantages such as lower system cost and simpler structure. So far, dominant control methods for proper power sharing can be mainly divided into two categories: active load sharing and passive load sharing. For active load sharing scheme, three common approaches are popular: master-slave control (MS), centralized control and average current control. The common of three approaches is the need of communication line among the parallel modules. On the other hand, most of the recent research is focused on passive load sharing (decentralized control method) e.g., droop control. As a decentralized control method, parallel modules can operate independently since no communication among the sources is needed.
2015-09-15
Technical Paper
2015-01-2409
Constanza Ahumada S., Seamus Garvey, Tao Yang, Patrick Wheeler, Herve Morvan
This paper considers the electromechanical interconnection between the electrical power system of the More Electric Aircraft (MEA) and the shaft connecting the engine to the generator. In order to probe the existing coupling between these two systems and therefore the necessity of studying them together, the effect of an electric load impact on the mechanical system of the MEA will be analyzed. As the MEA concept, replaces the pneumatic, hydraulic and mechanical systems by electrical systems, the electrical power rating of the MEA is considerable higher than the power rating of existing aircraft and consequently new challenges arise. A larger electrical power system implies larger generators and higher power loads, which can have higher associated electrical transients. Moreover, unlike in previous aircraft and most ground based electrical power systems, in the MEA the short term changes in power tend not to be small compared to the total load in the system.
2015-09-15
Technical Paper
2015-01-2406
Hendrik Strummel, Frank Thielecke
Fuel cell technology will play a decisive role in the process of achieving the ambitious ecological goals of the aviation industry. But apart from its obvious environmental advantages, the integration of fuel cell technology into commercial aircraft represents a challenging task in terms of operational and economical aspects. Since fuel cell systems are currently exposed to an intense competition with well-established power sources onboard an aircraft, engineers are in pursuit of highly efficient and particularly lightweight fuel cell systems. Supported by model-based design in conjunction with elaborate optimization technics this pursuit led to highly specialized systems. These systems tend to use their components to full capacity, which typically implies marginal system robustness. In consequence, preliminary design studies propose fuel cell systems that are sensitive to partial faults, or even to the slightest deviation, or degradation of their components’ behavior.
Viewing 1 to 30 of 16906