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Technical Paper

Proposal for Relaxation of Airspace Restrictions Based on Flight-Continuation Possibility of UAVs in Event of Failure

2024-03-05
2024-01-1912
The flight area of drones and other unmanned aerial vehicles (UAVs) had been highly restricted but has been relaxing, including flights beyond the scope of sight. Deregulation without aircraft-reliability improvement increases the risk of accidents. However, demanding high reliability for all aircraft leads to an increase in the price of the aircraft. Therefore, if airspace restrictions are relaxed for more reliable aircraft, the cost of higher reliability and its benefits can be balanced. This will improve efficiency and optimize cost-effectiveness. The purpose of this proposal is to balance the cost of aircraft-reliability improvement (which allows flight to continue in the event of a failure) and its advantages. Specifically, the author proposes rules that apply more relaxed airspace restrictions to UAVs with higher FCLs (Flight Continuity Possibility Levels) and stricter airspace restrictions to those with lower FCLs.
Research Report

Legal Issues Facing Automated Vehicles, Facial Recognition, and Privacy Rights

2022-07-28
EPR2022016
Facial recognition software (FRS) is a form of biometric security that detects a face, analyzes it, converts it to data, and then matches it with images in a database. This technology is currently being used in vehicles for safety and convenience features, such as detecting driver fatigue, ensuring ride share drivers are wearing a face covering, or unlocking the vehicle. Public transportation hubs can also use FRS to identify missing persons, intercept domestic terrorism, deter theft, and achieve other security initiatives. However, biometric data is sensitive and there are numerous remaining questions about how to implement and regulate FRS in a way that maximizes its safety and security potential while simultaneously ensuring individual’s right to privacy, data security, and technology-based equality.
Technical Paper

Research on Subjective Rating Prediction Method for Ride Comfort with Learning

2020-09-30
2020-01-1566
Suspension is an important chassis part which is vital to ride comfort [1]. However, it is difficult to achieve our targeted comfortability level in a short time. Therefore, improving efficiency of damper development is our primary challenge. We have launched a project which aims to reduce the workload on developing dampers by introducing analytical approaches to the improvement of ride comfort. To be more specific, we have been putting effort into developing the damping force prediction, the vehicle dynamics prediction and subjective rating prediction. This paper describes subjective rating prediction method which output a subjective rating corresponding to the physical value of the vehicle dynamics with deep learning. As a result of verification using objective data which was not used for learning process, DNN (Deep Neural Network) prediction method could fairly precisely predict subjective rating of the expert driver.
Journal Article

Optimization of Spatially Varying Fiber Paths for a Symmetric Laminate with a Circular Cutout under Remote Uniaxial Tension

2015-09-15
2015-01-2609
Minimizing the stress concentrations around cutouts in a plate is often a design problem, especially in the Aerospace industry. A problem of optimizing spatially varying fiber paths in a symmetric, linear orthotropic composite laminate with a cutout, so as to achieve minimum stress concentration under remote unidirectional tensile loading is of interest in this study. A finite element (FE) model is developed to this extent, which constraints the fiber angles while optimizing the fiber paths, proving essential in manufacturing processes. The idea to be presented could be used to derive fiber paths that would drastically reduce the Stress Concentration Factor (SCF) in a symmetric laminate by using spatially varying fibers in place of unidirectional fibers. The model is proposed for a four layer symmetric laminate, and can be easily reproduced for any number of layers.
Journal Article

A Simulation and Optimization Methodology for Reliability of Vehicle Fleets

2011-04-12
2011-01-0725
Understanding reliability is critical in design, maintenance and durability analysis of engineering systems. A reliability simulation methodology is presented in this paper for vehicle fleets using limited data. The method can be used to estimate the reliability of non-repairable as well as repairable systems. It can optimally allocate, based on a target system reliability, individual component reliabilities using a multi-objective optimization algorithm. The algorithm establishes a Pareto front that can be used for optimal tradeoff between reliability and the associated cost. The method uses Monte Carlo simulation to estimate the system failure rate and reliability as a function of time. The probability density functions (PDF) of the time between failures for all components of the system are estimated using either limited data or a user-supplied MTBF (mean time between failures) and its coefficient of variation.
Technical Paper

Development of Advanced Life Support Systems Control Software Considering Computational Effort and Mathematical Validity

2007-07-09
2007-01-3025
A habitation experiment using the Closed Ecology Experiment Facilities was started in 2005. In the future, the stays will be gradually extended. We have been developing the three layered control software for a Control Computer System of the Closed Ecology Experiment Facilities in order to back up the habitation experiments. In this paper, we will show the development of an operation scheduling system for one of the three layers, such as at the planning and scheduling level, and discuss the development of a scheduling algorithm that does not cause the complexity of the ALS scheduler to be exponentially increased.
Technical Paper

Electrical Modeling and Simulation with Matlab/Simulink and Graphical User Interface Software

2006-11-07
2006-01-3039
This paper describes modeling and simulation technologies used to simulate the electrical systems of Army vehicles using Matlab/Simulink coupled with graphical user interface software. The models were built using Mathworks' Matlab/Simulink software in conjunction with the SimPowerSystems Toolbox, a toolkit provided by Mathworks that provides models of basic electrical components such as capacitors and inductors, in addition to more advanced components such as diodes and IGBT's. The current results of this ongoing effort are presented and discussed.
Technical Paper

Power Management Software Interfaces Standard

2006-11-07
2006-01-3034
The current system requirements for the power management subsystem and ground combat vehicles for the Future Combat System require higher power and voltages for greater energy efficiency, advanced mobility, lethality and survivability. Efficient and reliable electrical power management is an essential capability within current force ground combat vehicles and will become even more important with the increased electrical power demands of future force vehicles which will exceed the capabilities of onboard power generation/storage technologies. This paper describes how to meet the aforementioned power distribution challenges through the development of a power management software interfaces standard that will provide the flexibility required by various programs and vehicles yet still provide a consistent framework for software development providing a consistent environment for all future Army programs.
Technical Paper

Estimation of Flows of Carbon and Oxygen in the CEEF System Based on Data Collected in a Stable Phase of Sequential Crop Cultivation Lasting More than 100 Days

2005-07-11
2005-01-3108
Closed habitation experiments are to be carried out using Closed Ecology Experiment Facilities (CEEF) from 2005 to 2009. The last target of duration of closed habitation is four months. Preliminary study and testing have been conducted in order to start the closed habitation experiments. In 2004 as the last year of the preliminary test phase for the 2005–2009 experiments, periodical harvesting from staggered cultivation of 23 crops including rice, soybean, peanut, and sugar beet was continued during 103 days. In order to balance with metabolisms of humans (named as “eco-nauts”) and animals, it is necessary to stabilize production of edible and inedible biomass, CO2 uptake and O2 production of crops. Although biomass production decreased rapidly during first five weeks of the 103-day period, it was relatively stable during last ten weeks. Average major foodstuffs in the harvested edible biomass met the requirement of two Eco-nauts although several minor ingredients were insufficient.
Technical Paper

A Simulation Model for the CEEF Behavioral Prediction System

2003-07-07
2003-01-2547
For validation of operation schedules for the Closed Ecology Experiment Facilities (CEEF), development of the CEEF behavioral prediction system (CPS) has been started. The CPS will be simulated using the CEEF operation schedule. The CPS will gather data on quantities of materials in each component of the CEEF and operational status of each component at the start of the simulation, and configure them as the initial conditions of the simulation. For requirements of experiments, the simulation program for the CPS should be easy to adapt for changes of components and object materials. Because the CEEF is a nonlinear system, available period of the simulation is important. A flexible algorithm for the changes was developed. The simulation was available for three days to validate.
Technical Paper

Effects of Small Disturbances Caused by Changes of Surrounding Conditions on the Small Positive Pressure Control System of the CEEF

1999-07-12
1999-01-1985
The closed ecology experiment facility (CEEF) has a small positive pressure control system consisting of rubber buffers and a mechanical subsystem. In the present study, effects of small temperature disturbances caused by changes of surrounding conditions on the pressure control system are investigated experimentally and in numerical simulations. Though solar radiation causes a pressure disturbance in the facility, choosing the proper diameter of ducts which connect the rubber buffers to the modules, the rubber buffers can follow fluctuations of low frequency, like daily atmospheric fluctuations and pressure changes caused by temperature control of the facility’s air conditioners, and can cut off those of high frequency due to changes of environmental conditions.
Technical Paper

Numerical Analysis for the Small Positive Pressure Control System of CEEF

1997-07-01
972516
It is necessary to develop a small positive pressure control system for the closed ecology experiment facility (CEEF) to protect against over-differential pressure loading. In the present study, a numerical method was developed to calculate the quantity of state of the closed module, which is fitted with rubber buffers, for the small positive pressure control system. Experiments to examine the pressure change of the closed module were carried out at CEEF. Comparison of calculated and experimental results showed that the present dynamic simulation is suited to estimating the quantity of state of the closed module.
Technical Paper

Material Flow Simulation Software for CEEF: Closed Ecology Experiment Facilities

1995-07-01
951537
IES (Institute for Environmental Sciences) is now constructing CEEF at Rokkasho, Aomori, Japan. The simulation for material flow is made based on a system model of CEEF, which includes one person and 7 plant species of Rice, Soybean, Komatsuna, Sesame, Tomato, Potato and Buckwheat. In this simulation software, plants, human and their support systems are mathematically defined and material flows such as O2, N2, CO2, waters, fertilizers and organic matters are computed. This software simulates only material flow and but does not simulate thermal dynamics of the environment. The simulation result showed reasonable material flows in a closed system.
Technical Paper

Construction of CEEF is Just Started CEEF:Closed Ecology Experiment Facilities

1995-07-01
951584
Construction of Closed Ecology Experiment Facilities (CEEF) is started in Rokkasho village of Aomori prefecture, the northern part of Honshu island in Japan. CEEF consist of Closed Plant Experiment Facility (CPEF) and Closed Geo-Hydrosphere Experiment Facility (CGEF) with capability to simulate ecological systems containing plants, animals, human, trees and sea living things. These biospecies are selected according to experimental plans and are maintained their lives in controlled environments. Recyclings of materials circulating in the closed system of CEEF are made mainly utilizing physical chemical treatments. The construction of CEEF will be completed by 1998. This paper mainly describes design of CPEF.
Technical Paper

Airborne Laser Radar Investigations of Clear Air Turbulence

1966-02-01
660190
Conclusions based on the airborne experiments with laser radars are summarized in this paper. Details of the equipment and the flight procedures will be displayed during the oral presentation at the conference.
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