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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.

In the future, there will be a continued presence of man in space. This may become realized with a simple platform, or possibly with a fully developed space station. In any case, the Life Sciences Division of NASA sees an opportunity for future studies involving long duration 0 gravity exposure. Because of the automation required for an unmanned, man-visited platform, it appears to be the greatest challenge. Thus, this paper will discuss the type of space platform/station presently being considered, the kind of life sciences facility(or laboratory) which would be required, and the scientific questions and experiments which might be carried out on a space platform/station. The need for a space platform/station for Life Sciences is also addressed as well as specific animal requirements.

The Advanced Programs Office in the Life Sciences Division at Ames has performed a survey and analysis of hardware and operational requirements necessary for supporting plant and animal research onboard the Space Station. This research may be conducted internal to a dedicated pressurized module, distributed among several modules, and on external platforms and free flyers. Hypothetical experiments have been defined and integrated into 90 day missions to allow analysis of crew activities and timelines, resource requirements (e.g. power, weight, and volume), equipment layouts, and alternative levels of equipment automation. Where these analyses have shown critical areas for automation, conceptual designs have been developed to evaluate feasibility. To stay within current Space Station resource allocations, approximately 85% of the planned life science experiment tasks must be automated.

The Centrifuge Accommodation Module (CAM) will be the home of the fundamental biology research facilities on the International Space Station (ISS). These facilities are being built by the Biological Research Project (BRP), whose goal is to oversee development of a wide variety of habitats and host systems to support life sciences research on the ISS. The habitats and host systems are designed to provide life support for a variety of specimens including cells, bacteria, yeast, plants, fish, rodents, eggs (e.g., quail), and insects. Each habitat contains specimen chambers that allow for easy manipulation of specimens and alteration of sample numbers. All habitats are capable of sustaining life support for 90 days and have automated as well as full telescience capabilities for sending habitat parameters data to investigator homesite laboratories.

Life sciences research facilities planned for the U.S. Space Station will accommodate life sciences investigations addressing the influence of microgravity on living organisms. Current projects within the Life Sciences Space Station Program (LSSSP), the Life Sciences Space Biology (LSSB) and Extended Duration Crew Operations (EDCO) projects, will explore the physiological, clinical, and sociological implications of long duration space flight on humans and the influence of microgravity on other biological organisms/systems. Initially, the primary research will emphasize certifying man for routine 180-day stays on the Space Station. Operational crew rotations of 180 days or more will help reduce Space Station operational costs and minimize the number of Space Transportation System (STS) shuttle flights required to support Space Station.

The relative importance of life sciences in spaceflight depends on the nature of the: mission. For brief missions to low earth orbit, such as Shuttle flights, issues involving health concerns, life support, or crew factors present fewer challenges than would longer flights, e.g., those planned for Space Station. For missions of exploration, such as a Mars expedition, the life sciences are not only important to the safety and success of the mission, they are on the critical path to being able to embark on the mission at all. This paper presents a brief history of the role of life sciences in the space program and describes the characteristics of exploration missions that impact life sciences requirements. It concludes by outlining what needs to be done if the very demanding life sciences requirements of exploration missions are to be supported.

The paper reviews technical trends in the development of life support systems for future manned space missions. Although open loop systems have been used to date, future designs for installations in permanent micro-gravity orbit, long duration transport and ultimately, lunar or planetary bases will rely on regenerative processes to reduce the penalties associated with on-board storage and the resupply of consumables from Earth. In the medium term, these processes will utilise physico-chemical methods, typically to recover metabolic oxygen from respiratory carbon dioxide and fresh water from contaminated water. Food and waste will continue to be treated as open loop consumables and expendables. Later, as sufficient terrain becomes available, lunar or planetary habitats will begin to use a combination of biologically derived and physico-chemical processes to process waste, recycle organic nutrients and produce food.

Thermo-chemical-mechanical (TCM) feedstock conversion (FC) systems originally developed for high temperature conversion of domestic solid feedstock or blends to useful liquid and gaseous fuels are examined for advanced life support (ALS) applications in spacecraft. Recently, exploratory investigations with these TCM-FC systems to use or sequester CO2 have led also to a focus on the production of useful chemicals and chars (activated carbon, humates, CO2 scrubbers, chelating and detoxifying agents, etc). TCM systems can process solid blends with catalysts, adsorbants, reactants, carbon dioxide, steam, air, oxygen, natural gas and liquids. This study considers applications of CCTL’s laboratory scale TCM-FCs for the conversion of the solid waste into sterile and useful gases, liquids or chars on long space missions. TCM units are extrusion systems, and are more adaptable to zero gravity than fluidized bed systems or other systems that rely on gravity.

Lunar base construction study has been conducted under the sponsorship of many Japanese industries to amend the man tended lunar outpost study carried by NASDA. Permanent lunar base construction is to be constrained by the ability of the usable transportation system carrying the basic modules composing lunar base itself. Based upon the experiences of Antarctic Research Expedition and of designing International Space Station now going on it was assumed the initial permanent lunar base has to be composed of two habitats and one power module for letting possible to alive 8 crews, and has to be expanded by adding three or four modules in every year for improving the easiness of livingness. In early stage of construction, crew members have to live and work using only two habitat modules with getting the electric power from power module, therefore the minimum self support functions except the food and oxygen supplying have to be attached to the habitat modules.

The Systems Integration, Modeling and Analysis (SIMA) element1 of the National Aeronautics and Space Administration (NASA) Advanced Life Support (ALS) Project conducts on-going studies to determine the most efficient means of achieving a human mission to Mars. Life support for the astronauts constitutes an extremely important part of the mission and will undoubtedly add significant mass, power, volume, cooling and crew time requirements to the mission. Equivalent system mass (ESM) is the sum of these five parameters on an equivalent mass basis and can be used to identify potential ways to reduce the overall cost of the mission. SIMA has documented several reference missions in enough detail to allow quantitative studies to identify optimum ALS architectures. The Mars Dual Lander Mission, under consideration by the Johnson Space Center (JSC) Exploration Office, is one of those missions.

A functional analysis was performed to identify life support functions and interrelationships required for manned space exploration. Methods were identified to provide each of these functions, ranging from resupply of consumables to totally regenerative processes. Specific mission characteristics and their effect on advanced life support requirements are outlined. A preliminary assessment is made as to which life support functions are critical for missions of various duration. Technologies which have been selected for Space Station Freedom and associated degrees of closure are discussed and areas for future work are suggested.

NASA's Constellation Program, which includes the mission objectives of establishing a permanently-manned lunar Outpost, and the exploration of Mars, poses new and unique challenges for human life support systems that will require solutions beyond the Shuttle and International Space Station state of the art systems. In particular, the requirement to support crews for extended durations at the lunar outpost with limited resource resupply capability will require closed-loop regenerative life support systems with minimal expendables. Planetary environmental conditions such as lunar dust and extreme temperatures, as well as the capability to support frequent and extended-duration Extra-vehicular Activity's (EVA's) will be particularly challenging.

For botanical experiments with durations of several months (EURECA BOTANY FACILITY and COLUMBUS GRAVITATIONAL BIOLOGY FACILITY) consumables like water, carbondioxide, oxygen and phytotoxin removal gas may contribute significantly to the weight of a Life Support Subsystem (LSS). Since the amount of such consumables has a significant influence on the optimum choice of the LSS, a literature survey has been performed to obtain realistic values which may be used for preliminary design purposes. Based on a comparison of the likely performance requirements the LSS of Orbital Botanical Facilities (OBF) and the Environmental Control and Life Support Subsystem (ECLSS) of the carrier, various LSS concepts are discussed which interact to a varying degree with the ECLSS. Interaction means in this case that the ECLSS is used as a resource for the consumables needed by the LSS. Advantages and disadvantages of such interaction, in particular weight savings and technical complexity are addressed.

Due to the late flight opportunity for the BOTANY FACILITY on the second EURECA mission a sized down facility, referred to as the MINI BOTANY FACILITY (MBF), to be flown in a re-entering capsule, for example the Russian BIOKOSMOS, is currently being studied. As a minimum, the following subsystems are baselined for the MBF: Experiment container/-cuvette, visualization, illumination, life support, thermal control, waste control and fluid supply. The paper addresses firstly the impact of the new boundary conditions (e.g. operation in pressure controlled environment, much shorter mission duration) on the selection of viable concepts for the Life Support Subsystem (LSS). Next a number of options for soil moisture control is discussed and analysed. Finally, the pre-development of components and a miniaturized sensor for soil moisture is addresssed.