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Due to the strengthening of environmental laws and an increasing concern about sustainability into society, it becomes important in modern corporate management to address these issues and recognize them as a major competitive advantage. The demand for products with enhanced environmental profiles is becoming an essential goal within new product concepts and development. When a new truck line was launched to the market in 2006, the opportunity arose to conduct the first study in the Brazilian automotive industry, which should provide a holistic view of the environmental profile of a product during its entire life through life cycle analysis (LCA). This paper presents the results of the application of this new approach to heavy-duty vehicles.

There is a growing awareness of the business value of sustainable practices. Life cycle tools can be used to design and continually improve future vehicles as well as provide bottom line cost savings, increase the recycled content and recyclability of products, and reduce the hazardous substance content in products. Data collection and management procedures as well as advanced life cycle technologies and tools have been developed and implemented at some corporations to meet the global market demands to increase the recycled content and recyclability of automobiles and to reduce the hazardous substance content in automobiles. Voluntary take-back legislation in Europe, as well as strict domestic and international labeling and reporting requirements for plastics and hazardous substances have prompted automotive manufacturers to aggressively evaluate (1) the regulated substances contained in their automobiles and (2) the recyclability of their automobiles.

Fuel choices are being made today by consumers, industry and government. One such choice is whether to use reformulated gasoline to replace regular unleaded gasoline. A second choice involves the source of crude oil, with synthetic crude oil from tar sands currently expanding its share of the Canadian supply. Decision makers usually work with the direct economic consequences of their fuel choice. However, they generally lack the knowledge to measure environmental aspects of different fuel systems. This paper uses Life Cycle Value Assessment (LCVA) to demonstrate how the life cycle environmental aspects can be compared for alternative fuel choices. LCVA is an engineering decision making tool which provides a framework for the decision maker to consider the key economic and environmental impacts for the entire life cycle of alternative products or process systems.

Transportation, with its high energy consumption, is commonly recognized as a major contributor to local, regional, and global environmental impacts. With around 95% of transportation energy originating from petroleum and an increasing emphasis on the associated environmental impacts, alternative transportation fuels are receiving great attention from industry, government, researchers, and the public. When the motivation for developing alternative fuels is to reduce environmental impact, a rigorous tool is needed for comparing the effects of very different alternative and conventional fuels. Such an evaluation tool must consider not only the effects of fuel combustion, but also the effects of producing, refining/processing, distributing, and disposing of wastes associated with that fuel… in other words, the life cycle effects of the fuel.

Heavy Duty Diesel Truck (HDDT) drivers are required by law to rest 8 hours for every 10 driving hours. As a consequence, the trucks are idled for long periods of time to heat or cool the cabin, to keep the engine warm, to run electrical appliances, and to refrigerate or heat truck cargo. This idling results in gaseous and particulate emissions, wasted fuel and is costly. Various technologies can be used to replace truck idling, including heaters, auxiliary power units, parking space electrification, and heating and air conditioning units in the parking space. In this paper the results of a life cycle analysis are reported giving the associated emissions savings and ecological burdens of these four technologies compared to truck idling. In this analysis the savings related to reduced engine maintenance and increased engine life are included. The fuel consumed and emissions produced by a truck engine at idle was obtained from experiments performed at Aberdeen Test Center (ATC).

Failure mode identification test such as Failure Mode Verification Testing® (FMVT), Highly Accelerated Life Testing (HALT) and Multiple Environment Over Stress Test (MEOST) have provided a solid means of identifying failure modes quickly. Many experts in these different methods have asserted that making life predictions from these tests will eventually be possible. This paper will explore the current state of making those correlations and detail several methods that have been successful in providing correlation between failure mode testing results and field life data. The short-term and long-term potential for life prediction and population synthesis will be discussed.

The 48V mild-Hybrid system uses a 48V Lithium - Ion battery pack to boost the engine performance, to harness recuperative energy and to supply the accessory boardnet power requirement. Thermal management of the 48V battery pack is critical for its optimal utilization to realize the mild hybrid functionality, to meet CO2 reduction targets and useful life particularly under usage in hot ambient conditions. This paper discusses the various challenges and options of thermal management for the 48V battery pack based on the usage pattern and environmental conditions. The lifetime for a passively cooled battery pack is estimated for a typical Indian usage pattern. Active-air cooling is evaluated for the thermal management of the 48V mild-Hybrid battery pack. The tradeoffs are compared in terms of availability of hybrid functions and battery life.

It is experimentally known that the surface color of bearing balls gradually becomes brown during long term operation of the bearings under appropriate lubrication conditions. That exhibits the possibility of an estimation method for residual life of ball bearings without any abnormal wear on the surfaces by precise color measurements. Therefore, we examined what set colors on bearing balls by surface observation using scanning electron microscopy and subsurface analysis using transmission electron microscopy. Results showed that an amorphous carbon layer had gradually covered ball surfaces during operation of the bearings. The layer not only changed ball color but also made overall ball shapes closer to a complete sphere. The report also introduces a uniquely developed color analyzer which enabled color measurements on metallic surfaces, such as the above-mentioned balls.

Most popular practice for analyzing the Subsystem failures in commercial vehicles is physical testing. These physical tests are carried out by three tests; Endurance testing, Accelerated Endurance Testing and Rig test simulation. All the three methods are costly and repetitive iterations of these tests is not economical. Therefore, in our organization, we established a method in virtual domain in order to reduce the repetitive iterations and also reduction in time consumed per iteration. General practice in our organization for Finite Element Analysis (FEA) calculation was inclusive of Model preparation, Transient analysis using Nastran. The results from the Transient analysis are used for performing fatigue analysis in fatigue software. In this process, Transient analysis and Model preparation are very much time consuming processes. Model preparation cannot be reduced, but to reduce the transient analysis time, we established a method in frequency domain (vibrational fatigue) [1].

Three separator materials; nylon (NY), polypropylene (PP) and polyphenylenesulfide (PPS), were evaluated by accelerated cycle test of 35AH aerospace NiCd cells. The failure mode of cells with the NY separator is different from the other. The result of these test suggest that the NY separator will satisfy with required mission life of 1000 cycles in geosynchronous earth orbit (GEO) and 20000 cycles in low earth orbit (LEO) under the condition of controlled cell temperature at 20°C. Also, the washed NY separator was compared with the unwashed NY separator by semi-real GEO cycle. During early cycles, the washed separator cells showed a slight degradation of cell capacity as compared with the unwashed separator cells. After 1000 cycles, the washed separator cells show greater capacity degradation than the washed cells.

The life of a wheel bearing unit under real load conditions can now be calculated based on actual load histories. These load histories are recorded over many small but discrete time slices where the speed and loads within each time slice can be regarded as constant. This enables the equivalent load Peqv for each time slice to be evaluated by means of the classical bearing life theory of Lundberg and Palmgren. The relative damage contributed by each time slice is then obtained, and eventually, the overall probabilistic damage from the load histories can be established by accumulating the damage derived from each individual time slice. From the damage distribution, the resultant equivalent load PEQV, representing one/several sets of road recordings, can be evaluated using the Palmgren-Miner rule. This resultant equivalent load is then used to evaluate the bearing life by re-employing the bearing life theory of Lundberg and Palmgren.

Nowadays, bearings for motorcycle engines are required to be compact and light weight and have a considerably high performance. In order to meet these requirements, two measures were developed, that is High Refining Steel (HRS) and Special Heat Treatment (SH Treatment). In this paper described are the characteristics of HRS and SH Treatment and the results of investigation on them. The investigation results show that bearings of HRS and bearings with SH Treatment have more than twice longer life than standard bearings, particularly the bearings with SH Treatment have longer life even under lubricating conditions with a low viscous lubricating oil or with a contaminated lubricating oil. As a matter of fact, the bearings of HRS and the bearings with SH Treatment are used for the motorcycle engines and show excellent performances.

Several aircraft accidents in the past few years which have been attributed to corrosion and fatigue, have added to the concern on ageing aircraft, and understandably resulted in questions also being directed towards engines. The ageing process does have an effect on engines, but unlike airframes, engines have always been subjected to periodic disassembly, inspection, and rework/repair/replacement, either on a whole engine or modular basis. All the available evidence shows that the total control process results in a satisfactory situation, with no indication of lowering reliability or safety as the fleet ages. This paper looks at the various fleet statistics, and then reviews the design procedures which produce engines with inherent integrity into old age, and the in-service procedures which confirm and preserve it. Characteristics of some of the major components are discussed, and some further points are suggested in which engines differ from airframes.

Stainless steel grades are now widely used for automotive exhaust systems, driven by the need to increase their durability and to reduce their weight. Exhaust Manifolds are subjected to more severe conditions and peak gas temperatures of 1000°C could be reached in new downsized gasoline engines. Also, longer guaranties are now required. This evolution is a direct consequence of the effort to decrease automotive pollutant emissions with new environmental regulations throughout the world. The paper will deal with the thermal-mechanical fatigue (TMF) damage prediction of fabricated automotive exhaust manifold fixed to the engine. A dedicated lifespan prediction approach was created based on elasto-viscoplastic behavior and damage models identification from different thermal-mechanical tests.

In this paper, a CAE (Computer-Aided Engineering) methodology to simulate the vibration test and predict fatigue life of head lamp bulb shield is presented. A modal analysis is performed first to determine the critical elements from the strain energy density distribution patterns. A random vibration frequency response analysis is then performed to monitor the stress response power spectral densities (PSDs) for critical elements due to the g-load input PSDs, measured at the mounting point in all three directions. Fatigue life can be estimated based on the stress response PSDs and material S-N curve by using Dirlik's method. The fundamentals for frequency domain fatigue analysis are reviewed and a case study with test correlation is then presented.

In the present paper a degradation assessment and life prediction method has been proposed for electro-hydraulic shift valve applied to control wet shift clutch in Power-shift steering transmission (PSST). Unlike traditional analysis of contaminant sensitivity, our work is motivated by the failure mechanisms of abrasive wear with a mathematic model. Plowing process included in abrasion will consecutively increase the roughness of mating surfaces and thereby enlarge the clearance space for leaking more fluid. It is an overwhelming wear mechanism in the degradation of shift valve within serious-contaminated fluid. Herein a mathematic model for assessment and prediction is proposed by considering particle morphology and abrasion theory. Such model has been verified for its applicability and accuracy through comparison between theoretical and experimental results. Assuming the proposed model to be general, valve wearing behavior in any hydraulic system can be simulated.

Refuse Trucks are used to pick up garbage from houses. These trucks have huge robotic arms connected to the frame which are operated by hydraulic mechanism operated by the driver sitting inside the cab of the truck. The operator of the truck controls the robotic arm using a lever. Once the truck is positioned aside the garbage can, the operator moves the robotic arm outwards, grabs hold of the garbage can, picks up the garbage can and dumps the garbage into the truck. During this operation, the frame articulates and moves due to the frame suspension causing the cab to move along with the frame. This operation is performed about 1000 times a day, 5days a week for 12 years which could result in some amount of damage to the cab over its life. Since the time rate of application of the forces during the Automatic Side Loading operation is small compared to the lowest flexible mode of the cab, modal amplification is considered unlikely.

The Advanced Programs Office at NASA Ames Research Center has defined hypothetical experiments for a 90-day mission on Space Station to allow analysis of the materials necessary to conduct the experiments and to assess the impact on waste processing of recyclable materials and storage requirements of samples to be returned to earth for analysis as well as of non-recyclable materials. The materials include the specimens themselves, the food, water, and gases necessary to maintain them, the expendables necessary to conduct the experiments, and the metabolic products of the specimens. This study defines the volumes. flow rates, and states of these materials, Process concepts for materials handling will include a cage cleaner, trash compactor, biological stabilizer, and various recycling devices.

The NASA Lyndon B. Johnson Space Center (JSC) Life Sciences Space Station Program (LSSSP) will support the NASA goal of expanding human presence beyond the Earth into the solar system. The Biomedical Research Project (BmRP) is a major element of the LSSSP and is planning an onboard laboratory for studying the effects of microgravity on humans. During the Space Station era, the major emphasis for the BmRP is to identify and quantify the effects of reduced gravitational forces on humans and, if necessary, to develop methods and techniques which counteract or modify these effects to promote man's long-term health and productivity while working in space and upon return to Earth. A status of current science, technical, and programmatic planning activities that are being conducted at JSC to define BmRP requirements for the Space Station Program is presented herein.

Exploring worlds beyond Earth will require terrestrial life to survive and ultimately flourish in environments fundamentally different to those in which it has evolved. The effects of deep space and conditions on the surface of other worlds must be studied and compared to the Earth, to understand and reduce the risks to explorers, and to make full use of the broad research opportunities and scientific benefits offered by such unique environments. We are only beginning to learn about adaptations to the space environment -- key changes in terrestrial life may only be revealed over complete life cycles and across multiple generations beyond Earth. The demands and potential risks of exploring and inhabiting other worlds necessitate a detailed understanding of these changes at all levels of biological organization, from the smallest genetic alteration to impacts on critical elements of reproduction, development and aging.