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The vehicle Heating, Ventilation and Air conditioning (HVAC) system is designed to meet both the safety and thermal comfort requirements of the passengers inside the cabin. The thermal comfort requirement, however, is highly subjective and is usually met objectively by carrying out time dependent mapping of parameters like the velocity and temperature at various in-cabin locations. These target parameters are simulated for the vehicle interior for a case of hot soaking and its subsequent cool-down to test the efficacy of the AC system. Typically, AC performance is judged by air temperature at passenger locations, thermal comfort estimation along with time to reach comfortable condition for human. Simulating long transient vehicle cabin for thermal comfort evaluation is computationally expensive and involves complex cabin material modelling.

As space missions become longer in duration, the need to recycle waste into useful compounds rises dramatically. This problem can be addressed through the integration of human and plant modules in an ecological life support system. One of the waste streams leaving the human module is urine. In addition to the reclamation of water from urine, recovery of the nitrogen is important because it can be used as a nutrient for the plant module. A 3-step biological process for the conversion of nitrogenous waste (urea) to resource (nitrate) is proposed. Mathematical modeling was used to investigate the bioreactor system, with the goal of maximizing the ratio of performance to volume and energy requirements. Calculations show that separation of the two microbial conversions into two steps requires a smaller total reactor volume than combining them in a single bioreactor.

A compensatory tracking task (The Critical Tracking Task) requiring the operator to stabilize the output of an unstable system whose level of instability increases monotonically up to the critical point of loss of control is evaluated for its potential to discriminate between sober and intoxicated performances. Quantification of the results obtained in the laboratory controlled environment shows a great deal of promise, indicating that intoxicated failure rates of 50% for blood alcohol concentrations (BAC's) at or above 0.1% and 75% for BAC's at or above 0.14% can be attained with no sober failure rates. A high initial rate of learning is observed, perhaps due to the very nature of the task whereby the operator is always pushed to his limit, and the scores approach a stable asymptote after approximately 50 trials. Finally, the implementation of the task as an ignition interlock system in the automobile environment is discussed.

The Russian space program has maintained crews on long duration space flights nearly continuously over the past two decades. As a result, a strong emphasis has been placed on the development of regenerative life support systems. One of these systems is a urine processor which has been operating on-orbit since 1990. The U. S has also been developing urine processing systems to reclaim water from urine over the past twenty years. This paper will describe the two different technologies used for urine processing for long-term human presence in space and will compare the operating characteristics of the two systems.

A Simulation model for a distillation unit which is based on the description of some hardware by hydrodynamic patterns of “ideal mixing” is developed for solving problems of prediction of the Water Reclamation System from Urine (WRS-U) operation. The model reflects the system operation algorithm and enables simulation of process hardware. The structure of the Simulation Model (SM), formalized descriptions of some units and model program implementation are shown based OSS Mir's WRS-U. Computational results are compared with test data.

The introduction of compulsory blood alcohol tests on road crash casualties 15 years of age and older has provided hospital material for the study of alcohol related crashes and road trauma. A 2 year study of two major emergency departments in Melbourne hospitals was undertaken (1981-1982). Patients found to be alcohol positive (n.654) were matched against an equal number who were alcohol negative. Road user and licence status, blood alcohol level, injury patterns were studied as well as the demographic variables of age, sex, marital status and occupation. The study found significant differences existed in the variables between the two populations. The level of medical staff co-operation was fair. It is suggested that some changes to the overall system are required if the aims of the legislation are to be achieved.

To evaluate a driver's task and stress level objectively while maneuvering a vehicle, we paid attention for human's physiological responses under the condition. The eccrine sweat on a palm and a forehead, heart rate and a face temperature of a subject driver were monitored and measured continuously and quantitatively using the specified direct sweat measuring equipment, the electrocardiograph and the infrared thermometer respectively. As a result of having analyzed these data physiologically, we propose that the driver's stress level can be objectively determined by the quantity of eccrine sweat, changes of heart rate and changes of face temperature.

A long-term lunar outpost will require sustainable life support technologies that are capable of functioning for years with minimum resupply and maintenance. While life support resources such as water and air will remain in short supply, the availability of gravity, energy, and natural resources on the lunar surface allow for innovation in the design of outpost technologies, potentially including the adoption of terrestrial technologies previously not feasible for short duration microgravity flight. One technology with potential for such innovation is the water recovery system. Current spacecraft water recovery systems rely on oxidizing pretreatment chemicals to stabilize wastewater, as microgravity compatible distillation or filtration systems are prone to fouling and failure.

A new water recovery system designed towards fulfillment of NASA's Vision for Space Exploration is presented. This water recovery system is an evolution of the current state-of-the-art system. Through novel integration of proven technologies for air and water purification, this system promises to elevate existing technology to higher levels of optimization. The novel aspect of the system is twofold: Volatile organic contaminants will be removed from the cabin air via catalytic oxidation in the vapor phase, prior to their absorption into the aqueous phase, and vapor compression distillation technology will be used to process the condensate and hygiene waste streams in addition to the urine waste stream. Oxidation kinetics dictate that removal of volatile organic contaminants from the vapor phase is more efficient.

The Microbial Check Valve (MCV) is a reloadable flow-through canister containing iodinated ion exchange resin, which is used aboard the Shuttle Orbiter as a disinfectant to maintain water potability. The MCV exhibits a significant contact kill and imparts a biocidal residual I2 concentration to the effluent. MCVs in current use have nominal 30 day lives. MCVs baselined for Space Station Freedom will have 90 day lives, and will require replacement 120 times over 30 years. Means to extend MCV life are desirable to minimize resupply penalties. New technology has been developed for fully autonomous in situ regeneration of an expended MCV canister. The Regenerative Microbial Check Valve (RMCV) consists of an MCV, a packed bed of crystalline I2, a flow diverter valve, an in-line iodine monitor and a microcontroller. During regeneration, flow is directed first through the packed I2 bed and then into the MCV where the resin is replenished.

Numerous military and civilian occupations expose workers to high thermal stress, impairing performance and increasing injury risk. This problem is exacerbated for workers using encapsulating clothing ensembles (e.g., chemical or fire protective clothing). This paper reports on an effort by the authors to develop a man-mounted air-based cooling system that permits sustained operations under thermal stress. A desiccant (zeolite)-based heat pipe is under development that utilizes water as the heat transfer medium that is adsorbed by a zeolite bed. The cooling system is designed to integrate with a ventilated garment to exploit the body’s evaporative cooling capacity. Cooling efficiency is attained by blowing cool, relatively dry air over the user’s body surface and evaporating sweat. The system is designed to provide 300 L/min ventilation with a sustained temperature change (ambient – cooler output) ≥ 10 degrees C at ambient conditions = 32.2 degrees C, 30% RH.

Using Thermal Simulation to Model the Effects of Wind on the Mars Curiosity Rover Quality and Validation of Digital Designs for Aerospace and Defense Scaling LiDAR Optical Payloads from Drones to Miniature UAVs Using Sintered Fiber Metal Composites for Aircraft Acoustic Attenuation GaN Breaks Barriers RF Power Amplifiers Go Wide and High Test System Ensures Flawless Performance of Military RF Devices The Impact of Video Compression on Remote Cardiac Pulse Measurement Using Imaging Photoplethysmography Remote physiological measurement technique leverages digital cameras to recover the blood volume pulse from the human body. Sensitivity Simulation of Compressed Sensing Based Electronic Warfare Receiver Using Orthogonal Matching Pursuit Algorithm Calculate the sensitivity of a CS based EW receiver using two modulation schemes.

Closed Ecology Experimental Facilities, CEEF, is designed to regenerate everything required for living, such as air, water, and food. Researchers called “econauts” play a crucial role in maintaining the system in good order. CEEF must involve confinement, which is one of the major factors responsible for deterioration in crew health and performance. Two econauts repeated 7-day habitation in the CEEF 3 times in 2005. Blood cells, hormones and mood status were analyzed. Although clinically no problem, changes of mood status and a stress hormone correlated in an econaut. Characteristic changes were observed in leukocyte ratio. These data are essential in considering the effects of forthcoming long-term habitation in CEEF.

A vigilance study utilizing visual stimuli demonstrates one of the mechanisms of alcohol effects on human performance. The number of failures to respond to critical signals increases as a function of blood alcohol level. Using appropriate physiologic monitoring, it is possible to detect periods of drowiness with associated prolonged eyelid closures. Further insight into the mechanisms involved is gained when response failures are divided into eyes-open and eyes-closed failures. Alcohol produced a significant increase in eyes-closed (drowsy) failures but did not change eyes-open failures.

The Phystester, an ignition interlock system based on a predriving performance test, is evaluated. Results and observations from programs conducted by General Motors and other independent organizations are analyzed. The sensitivity of the psychomotor task offered by the Phystester to blood alcohol concentration, performance asymptoticity through distributed training, age, intelligence, drinking habits, sex, and digital dexterity is quantified. Performance on the Phystester task is shown to be significantly correlated with blood alcohol concentration and with performance on simulated driving tasks. The Phystester is shown to be capable of discriminating between sober and intoxicated individuals, the intoxicated rejection rate being dependent on the magnitude of the acceptable sober rejection rate.

This paper compares estimates of the proportion of driver fatalities in which the driver is legally intoxicated from two data sources, accident reports and toxicological reports of blood alcohol concentration (BAC). A total of 1,260 driver fatalities in Texas had BAC test results available for study. Of the legally intoxicated driver fatalities identified by BAC tests, 68 percent of the corresponding accident reports did not show alcohol as a contributing factor in the accident. Descriptive statistics based on BAC results by age and sex of the fatally injured driver, and by time and date of the accident are reported. In addition, the underreporting rate of alcohol involvement is described by age and sex of the driver fatality, and by investigating officer (local police versus DPS). The findings emphasize the need for better quality data on alcohol involvement in traffic accidents.

The focus of this research is on the development of a more energy efficient shortened liquid cooling/warming garment (LCWG) based on physiological principles comparing the efficacy of heat transfer of different body zones; the capability of blood to deliver heat; individual muscle and fat body composition as a basis for individual thermal profiles to customize the zonal involvement of the garment; and the development of shunts to minimize or redirect the cooling/warming loop for different environmental conditions, physical activity levels, and emergency situations. The total length of tubing in the LCWG is approximately 35% less, and the weight decreased by 45% compared to the LCVG currently used in space.

This paper reviews designs of urine distillation systems for spacecraft water recovery. Consideration is given to both air evaporation and vacuum distillation cycles, to the means for improving cycle performance (such as heat pumps, multistaging, and rotary evaporators), and to system concepts offering promise for future development. Vacuum distillation offers lower power consumption, at some increase in system complexity; air evaporation distillation is capable of providing higher water recovery efficiency, which could offset the lower power consumption advantage of vacuum distillation for long-duration missions.

Water reclamation from human urine will be the basis of the closed loop Water Recovery Management (WRM) system on Space Station Freedom (SSF). Pretreatment is necessary to collect and process urine, fix and prevent ammonia formation, inhibit microbial growth and prevent solids precipitation. Pretreatment must be accomplished immediately upon collection to prevent damage to urine collection and handling equipment. Currently, a chemical injection scheme is an integral part of the SSF Urinal design. The reagents used will be based on compatibility with Urinal and Urine Processor components, performance of necessary pretreatment functions, quality of reclaimed water, resupply costs and development risks. These factors are compared for various pretreatment methods currently under consideration for use on SSF.

Exhaustive testing and analysis of Vapor Compression Distillation technology has proven its overall readiness as a wastewater processor for the recovery of water in orbiting and interplanetary spacecraft. In conjunction with Boeing Aerospace and Electronics and the National Aeronautics and Space Administration, Life Systems' technical team has been focusing on verifying and improving performance characteristics, micro-gravity compatibility, reliability and maintainability aspects of the Vapor Compression Distillation design. Amassing thousands of hours of testing and recent breakthroughs in the area of peristaltic pump design, product water conductivity sensing and gas/liquid separation concepts have substantially increased the engineering and scientific database that has been accumulating over the past 29 years.