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Technical Paper

“Zero Defects”, Statistically Considered

2000-09-11
2000-01-2605
The requirement of “zero defects” is rapidly finding its way as a “standard” of quality in numerous quarters. This phrase has great psychological appeal, and is often taken literally at all levels in an organization even though quality motivation may be the intention. It is common to believe that when zero defects are found in the sample, this must be the case for “all the rest” as well. In this paper the technical side of “zero defects” is examined. We look at the statistics of zero defects and show what is implied about lot or process quality when zero defects is the actual sample outcome. The focus is on attribute measurements and includes some special cases where a significant measurement error exists and cases where a Bayesian statistical analysis may be appropriate.
Technical Paper

“Standardizing the Datasheet” Towards Auto-Code Generation Efficiency

2009-04-20
2009-01-0270
Software programs in non-application areas such as Board Support Packages, Hardware Abstraction Layers, signal processing and data acquisition are more or less very standard and common across many applications. These form a major part of the “platform” software, which changes very little. However, it is seen that many a time, efforts are spent resolving issues in the hardware dependent layers rather than concentrating on the application at hand, despite the fact that the software controlling the hardware has been developed many times. There are many reasons why this section of the software is rewritten many times over: different coding standards, different software architecture and layering concepts, the dreadful cut-and-paste methods, and so on. Introduction of a tool-based code configurator and generator eliminates access to the code and focuses on configuring a pre-written set of SW procedures. Advantages: Standardization, reuse and high levels of productivity.
Technical Paper

“Posture and Gait Control Enhancement Using Dermal Optical Sensitivity”

2004-07-19
2004-01-2484
Posture and gait controls underlie the fundamental physical and cognitive human factors necessary for astronauts’ safety and performance in Space. This central subsystem is adversely affected when exposed to an extreme or hostile environment. A specific stimulation, using dermal optical sensitivity, can be provided to the central nervous system to counteract peripheral stimulations due to microgravity as well as other negative stressors. We believe using dermal optical sensitivity-based stimulation can be key in the performance enhancement necessary to ensure human based space mission viability and success.
Technical Paper

“Personal Integrity” and Man-Machine Integration

1982-02-01
821348
A sense of “personal integrity” blocks pilot use of new information about how he thinks. Research on human performance under stress done over the past fifty years indicates increased rigidity and regression to earlier learned behavior in high stress, and in low Stress a shift in attention to any domestic situation or on the job controversy which is of higher stress than that of the job at hand, all without the pilot's knowledge. Informal surveys of commercial pilot training and commercial pilot attitudes towards these studies indicate that the study findings directly confront learned cultural responses. Pilot and trainer reactions prevent the information from being adequately investigated or formally taught. The findings are not written into training manuals and pilots who are informally given the information do not have adequate access to the knowledge when it is needed.
Technical Paper

“Fitting Data”: A Case Study on Effective Driver Distraction State Classification

2019-04-02
2019-01-0875
The goal of this project was to investigate how to make driver distraction state classification more efficient by applying selected machine learning techniques to existing datasets. The data set used in this project included both overt driver behavior measures (e.g., lane keeping and headway measures) and indices of internal cognitive processes (e.g., driver situation awareness responses) collected under four distraction conditions, including no-distraction, visual-manual distraction only, cognitive distraction only, and dual distraction conditions. The baseline classification method that we employed was a support vector machine (SVM) to first identify driver states of visual-manual distraction and then to identify any cognitive-related distraction among the visual-manual distraction cases and other non-visual manual distraction cases.
Technical Paper

srv-k Status Aboard the International Space Station During Missions 15 and 16

2008-06-29
2008-01-2191
The paper summarizes the experience gained on the ISS water management system during the missions of ISS-1 through ISS-16 (since November 2 2000, through December 31, 2007). The water supply sources and structure, consumption and supply balance at various phases of space station operation are reviewed. The performance data of the system for water recovery from humidity condensate SRV-K and urine feed and pretreatment system SPK-U in the Russian orbital segment are presented. The key role of water recovery on a board the ISS and the need to supplement the station's water supply hardware with a system for water reclamation from urine, water from a carbon dioxide reduction system and hygiene water is shown.
Technical Paper

[Interior] Configuration Options, Habitability and Architectural Aspects for ESA’s AURORA Human Mission to Mars Study

2005-07-11
2005-01-2850
This paper discusses the findings for [Interior] Configuration Options, Habitability and Architectural Aspects of a first human spacecraft to Mars. In 2003 the space architecture office LIQUIFER was invited by the European Space Agency’s (ESA) AURORA program committee to consult the scientists and engineers from the European Space and Technology Center (ESTEC) and other European industrial communities with developing the first human mission to Mars, which will take place in 2030, regarding the architectural issues of crewed habitats. The task was to develop an interior configuration for a Transfer Vehicle (TV) to Mars, especially a Transfer Habitation Module (THM) and a Surface Habitat (SHM) on Mars. The total travel time Earth - Mars and back for a crew of six amounts to approximately 900 days. After a 200-day-flight three crewmembers will land on Mars in the Mars Excursion Vehicle (MEV) and will live and work in the SHM for 30 days.
Technical Paper

Zoonoses and Enclosed Environments

1991-07-01
911513
The likelihood of transmission of potential disease agents between animals and man during spaceflight is a real concern. Development of disease exclusion lists for animals and refinement of animal containment units have been the principal means of providing protection to the crew members. Awareness of potential latent infections and a judicious use of the higher risk category of animals such as wild-caught nonhuman primates provides another level of protection. Use of high efficiency filters, gasketing, and differential air pressures have all enabled increasing levels of safety through containment of potential aerosol escape from animal habitats.
Technical Paper

Zero-Gravity Testing of a Waste Management System

1969-02-01
690644
This paper describes the testing of a waste management system designed and fabricated for use in a space vehicle. The system provides for the collection and inactivation of urine, feces, emergency diarrheal disorders, vomitus, and debris; the volumetric determination of each micturition; and onboard storage of the inactivated wastes within the waste management system compartment. The zero-gravity test program conducted in a KC-135 aircraft provided the primary verification of the performance of the waste collection and urine volume determination functions prior to actual space flight. The test hardware simulated the actual system to a high degree of fidelity with respect to operational characteristics of the airflow required in collection, mechanical functions and system pressure differentials, in order to minimize simulation errors.
Technical Paper

X-Ray Study of the Human Neck Motion Due to Head Inertia Loading

1994-11-01
942208
This study presents results from x-ray analysis of live human head/neck motion in sled test simulations of low-speed frontal, lateral, and rear-end vehicle impacts. The test subjects were 26 male and female adults, aged 22 to 61 years. Head/neck motion and the kinematic responses of each test subject were measured and analyzed by cineradiograph, high-speed film, accelerometers, and electromyography of the neck muscles. The methodology used may provide insight into the mechanism of neck injuries caused by the head inertia loading. The actual kinematic responses of the head/neck were found to be more complex than previously thought. The experimental results suggest that the most significant factor of the head/neck response is the initial curvature of the cervical and thoracic spine. Looking specifically at the early motion of the head and neck in rear-end impacts, the cervical forward curvature (lordosis) and the thoracic rearward curvature (kyphosis) were found to straighten.
Technical Paper

X-Ray Study of the Human Neck During Voluntary Motion

1979-02-01
790134
Radiographs were taken of the cervical spines of male subjects during voluntary motion from full flexion to full extension. Approximately 16 radiographs were taken during a period of 3 1/2 seconds. The resulting motions of the cervical vertebrae were analyzed. A simple pinned-link model of the spine under these conditions is presented.
Standard

Wrenches, Box and Open End Combination Twelve Point, High Strength, Thin Wall, Metric

2013-02-10
CURRENT
MA4535A
This SAE Metric Aerospace Standard (MA) provides dimensional, performance, testing and other requirements for high strength, thin wall, double head box and combination wrenches which possess an internal wrenching design so configured that, when mated with hexagon (6 point) fasteners, they shall transmit torque to the fastener without bearing on the apex of the fastener’s wrenching points. This standard provides additional requirements beyond ANSI B107.9 appropriate for aerospace use. Inclusion of dimensional data in this document is not intended to imply all of the products described therein are stock production sizes. Consumers are requested to consult with manufacturers concerning lists of stock production sizes.
Standard

Wrench, Spanner

2013-05-28
HISTORICAL
AS6018
This SAE Aerospace Standard (AS) covers adjustable and non-adjustable spanner wrenches generally used for aerospace machinery maintenance and for tightening and loosening hose couplings and hydrant caps. Inclusion of dimensional data in this document is not intended to imply all of the products described therein are stock production sizes. Consumers are requested to consult with manufacturers concerning lists of stock production sizes.
Technical Paper

WorldSID Prototype Dummy Biomechanical Responses

2001-11-01
2001-22-0013
The results of biomechanical testing of the WorldSID prototype dummy are presented in this paper. The WorldSID dummy is a new, advanced Worldwide Side Impact Dummy that has the anthropometry of a mid-sized adult male. The first prototype of this dummy has been evaluated by the WorldSID Task Group against previously established corridors for its critical body regions. The response corridors are defined in the International Organization of Standardization (ISO) Technical Report 9790. The prototype is the first version of the WorldSID dummy to be built and tested. This dummy has been subjected to a rigorous program of testing to evaluate, first and foremost its biofidelity, but also its repeatability. Following this initial evaluation, any required modifications will be incorporated into a pre-production version of the WorldSID dummy so that it rates “good” to “excellent” on the ISO dummy biofidelity scale – a rating exceeding that of all current side impact dummies.
Technical Paper

WorldSID 5th Percentile Prototype Dummy Development

2007-04-16
2007-01-0701
The WorldSID 5th percentile dummy, representing an average female, was developed in less than three years after the WorldSID 50th percentile dummy production release. This 5th percentile dummy was developed in the Integrated Project Aprosys (Advanced Protection Systems) under the European Commission Framework Program 6. This paper discusses the rationale for the WorldSID 5th percentile dummy design and development, and biofidelity evaluation results of head drop test, neck pendulum test and pendulum impact tests of the shoulder, thorax, abdomen and pelvis according to ISO TR9790 (ISO 1997) and Irwin (2002). The dummy was designed to host four units of 32 channel in-dummy Data Acquisition System with total 128 channel capacity. The head is constructed with PVC skin and plastic skull to simulate human head structure. The neck consists of a rubber design with metal discs, which can be tuned with rubber buffers.
Technical Paper

Workloads and Environment of Closed Habitation Experiments in CEEF (Closed Ecology Experiment Facilities) and Physio-Psychological Changes in Habitants (Eco-Nauts) During the Experiments

2005-07-11
2005-01-3005
The Closed Ecological Experimental Facilities (CEEF), designed to simulate material circulation, is an artificial closed agricultural ecosystem with plants, humans and animals. In the experiments starting from FY2005, habitants referred to as eco-nauts will be exposed to complex workloads and various CEEF environmental factors, which may influence their physio-psychological state, and lower their performance. Therefore, preliminary experiments were conducted on the workload-matched (11.1h work, 168h, airlock open) and the environment-matched condition (6.9h work, 24h, air circulation) to monitor physio-psychological changes. As a result, both experiment types were conducted as scheduled without any major problems, and no serious physio-psychological disorders were observed in the eco-nauts. One week closed habitation experiments will be performed as a preliminary step toward much longer (max. 4 months) experiments.
Technical Paper

Wood Energy - Viable Alternative

1979-02-01
790853
Norval Morey, President of Morbark Industries in Winn, Michigan has pioneered the concept of using the waste wood in our forests for energy. This concept calls for the removal from our forests of the dead, dying, diseased and overmature trees, as well as the undesirable species. This wood can be used to supply energy, while at the same time improve the stand and provide a better stock of trees to meet our more traditional needs, such as paper and lumber. From the studies that have been completed thus far, Mr. Morey has determined there is enough wood presently going to waste in our forests to more than offset present U.S. oil imports. The conversion to wood energy has already begun. Wood-fired systems are now commonplace in the forest products industry. Outside that industry a brick plant, a textile mill, a public electrical generating facility, a distillery, schools and other public facilities have already converted to wood as their major source of energy.
Journal Article

Why Should Auto-Generated C be Treated any Differently from Hand-Coded C?

2008-04-14
2008-01-0661
Many embedded software developers producing C code for automotive applications will be familiar with the MISRA C guidelines. These provide practical guidance in avoiding some of the common pitfalls associated with the C language. They were originally meant for automotive developers, but are now increasingly used in other critical sectors such as aerospace and medical devices. The commonly-held view, expressed in the MISRA C guidelines, is that all C code, whether hand-written or automatically generated, should be subjected to exactly the same verification and validation activities. However, as modeling language and automatic code generation techniques have evolved over the 10 years since the first edition of MISRA C, this advice may no longer be so relevant. This paper looks at some of the issues related to verification and validation of automatically-generated C code and identifies the situations in which the authors believe that a different approach is warranted.
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