8,529 research outputs found

    Meteoroid and debris special investigation group data acquisition procedures

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    The entire LDEF spacecraft was examined by M&D SIG for impact (i.e., craters greater than or = 0.5 mm and penetrations greater than or = 0.3 mm in diameter) and related features (e.g., debris, secondaries). During the various detailed surveys conducted at NASA Kennedy, approx. 5,000 impact related features were photodocumented, and their locations measured and recorded; an additional approx. 30,000 smaller features were counted. The equipment and techniques used by the M&D SIG permitted the determination and recording of the locations and diameters of the 5,000 imaged features. A variety of experimental and LDEF structural hardware was acquired by the M&D SIG and is presently being examined and curated at NASA Johnson

    LiDARPheno: A Low-Cost LiDAR-based 3D Scanning System for Plant Morphological Trait Characterization

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    The ever-growing world population brings the challenge for food security in the current world. The gene modification tools have opened a new era for fast-paced research on new crop identification and development. However, the bottleneck in the plant phenotyping technology restricts the alignment in Geno-pheno development as phenotyping is the key for the identification of potential crop for improved yield and resistance to the changing environment. Various attempts to making the plant phenotyping a “high-throughput” have been made while utilizing the existing sensors and technology. However, the demand for ‘good’ phenotypic information for linkage to the genome in understanding the gene-environment interactions is still a bottleneck in the plant phenotyping technologies. Moreover, the available technologies and instruments are inaccessible, expensive and sometimes bulky. This thesis work attempts to address some of the critical problems, such as exploration and development of a low-cost LiDAR-based platform for phenotyping the plants in-lab and in-field. A low-cost LiDAR-based system design, LiDARPheno, is introduced in this thesis work to assess the feasibility of the inexpensive LiDAR sensor in the leaf trait (length, width, and area) extraction. A detailed design of the LiDARPheno, based on low-cost and off-the-shelf components and modules, is presented. Moreover, the design of the firmware to control the hardware setup of the system and the user-level python-based script for data acquisition is proposed. The software part of the system utilizes the publicly available libraries and Application Programming Interfaces (APIs), making it easy to implement the system by a non-technical user. The LiDAR data analysis methods are presented, and algorithms for processing the data and extracting the leaf traits are developed. The processing includes conversion, cleaning/filtering, segmentation and trait extraction from the LiDAR data. Experiments on indoor plants and canola plants were performed for the development and validation of the methods for estimation of the leaf traits. The results of the LiDARPheno based trait extraction are compared with the SICK LMS400 (a commercial 2D LiDAR) to assess the performance of the developed system. Experimental results show a fair agreement between the developed system and a commercial LiDAR system. Moreover, the results are compared with the acquired ground truth as well as the commercial LiDAR system. The LiDARPheno can provide access to the inexpensive LiDAR-based scanning and open the opportunities for future exploration

    Conceptual design for the Space Station Freedom fluid physics/dynamics facility

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    A study team at NASA's Lewis Research Center has been working on a definition study and conceptual design for a fluid physics and dynamics science facility that will be located in the Space Station Freedom's baseline U.S. Laboratory module. This modular, user-friendly facility, called the Fluid Physics/Dynamics Facility, will be available for use by industry, academic, and government research communities in the late 1990's. The Facility will support research experiments dealing with the study of fluid physics and dynamics phenomena. Because of the lack of gravity-induced convection, research into the mechanisms of fluids in the absence of gravity will help to provide a better understanding of the fundamentals of fluid processes. This document has been prepared as a final version of the handout for reviewers at the Fluid Physics/Dynamics Facility Assessment Workshop held at Lewis on January 24 and 25, 1990. It covers the background, current status, and future activities of the Lewis Project Study Team effort. It is a revised and updated version of a document entitled 'Status Report on the Conceptual Design for the Space Station Fluid Physics/Dynamics Facility', dated January 1990

    Digital image colorimetry for determination of sulfonamides in water

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    This work aims to develop a digital image-based colorimetry for screening of sulfonamides (SAs) in water. It will be based on the determination of SAs in water, by analyzing the color response with an automatic image processing algorithm.Antimicrobial agents are considered emerging pollutants in water, because of their potential to accelerate spread of bacterial resistance genes, and due to their harmful effect to ecosystem through death or inhibition of natural microbiota. Sulfonamides (SAs) are an important antimicrobial group and it is widely used in both human and veterinary medicine. Studies have demonstrated that SAs are very mobile and highly available in soil with no bioaccumulation. Furthermore, these compounds seem to be quite resistant to biodegradation in surface water which can benefit contamination of aquatic environment. Thus, monitoring of SAs levels in water are very important to determine their aquatic risk assessment. Several methods for determination of SAs in water have been developed. Most of them are based on the coupling of high-performance liquid chromatography (LC) and mass spectrometry (MS). LC-MS is widely used due to their high sensitivity and specificity; however, this approach is very expensive and does not allow in situ analysis. Hence, development of field deployable screening methods is required. Methods based on digital image colorimetry have been broadly applied for point-of-care tests, forensic analysis and environmental monitoring. The digital image based methods are very promising as field screening techniques because they are fast, low cost, portable and easy handling methodologies

    Photoelastic Stress Analysis

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    Digital Documentation in Narrow Burial Spaces Using a 360° Borescope Prototype

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    This paper illustrates and discusses a novel method for the digital documentation of human remains in narrow spaces. A 360° borescope prototype made up of a panoramic camera and a lighting LED system was designed and assembled to acquire data in confined spaces for photogrammetric processing. A series of laboratory experiments were planned to assess the method’s validity. A modern concrete tunnel and a mock grave were surveyed using surveying instruments and a laser scanner, comparing the results with the borescope prototype. Then, data acquisition was moved to the field, i.e., in a real case study. Two burial vaults in a church containing human remains were selected and surveyed. The remains were accessible only from small breaches. The results show that using the 360° borescope is suitable for documenting narrow/confined spaces with minimum alteration of the scene. This result can be of interest for archaeological and forensic purposes, especially when the context is hardly accessible, with minimal intervention on the scene
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