3,854 research outputs found

    Investigating Machine Learning Techniques for Gesture Recognition with Low-Cost Capacitive Sensing Arrays

    Get PDF
    Machine learning has proven to be an effective tool for forming models to make predictions based on sample data. Supervised learning, a subset of machine learning, can be used to map input data to output labels based on pre-existing paired data. Datasets for machine learning can be created from many different sources and vary in complexity, with popular datasets including the MNIST handwritten dataset and CIFAR10 image dataset. The focus of this thesis is to test and validate multiple machine learning models for accurately classifying gestures performed on a low-cost capacitive sensing array. Multiple neural networks are trained using gesture datasets obtained from the capacitance board. In this paper, I train and compare different machine learning models on recognizing gesture datasets. Learning hyperparameters are also adjusted for results. Two datasets are used for the training: one containing simple gestures and another containing more complicated gestures. Accuracy and loss for the models are calculated and compared to determine which models excel at recognizing performed gestures

    From cellular vulnerability to altered circuit activity:a systems biology approach to study amyotrophic lateral sclerosis

    Get PDF
    The devastating effects of the brain losing its ability to control voluntary body movement are illustrated by diseases such as amyotrophic lateral sclerosis (ALS) - where the nerve cells that allow the brain to effectively communicate with muscles are progressively lost. Most of the ALS research traditionally revolves around the affected nerve cells, known as motoneurons, and aims to rescue their decline in function. Motoneurons are however part of larger networks in the nervous system and constantly receive, process and transmit signals. Therefore, even the smallest alteration of a single motoneuron will likely leave a mark on its connecting neurons and vice versa. Could it be that solely targeting the function of diseased neurons has unexpected effects in an already (mal)adapted network? To mimic ALS, we used the worm Caenorhabditis elegans engineered to express the human gene TDP-43. Dysregulated TDP-43 is considered a uniform hallmark of ALS and its expression in C. elegans causes severe paralysis. By developing and combining numerous technology-driven, mostly unbiased screening approaches we show that TDP-43 impedes neuronal function and causes an imbalance between stimulatory and inhibitory signals in the motor circuit. While functional output of repressed motoneurons could be restored via modulation of their activity, these interventions did not result in improved locomotion. Rebalancing the derailed motor circuit dynamics by combining multiple treatments, however, effectively restored movement. Because of the high degree of similarity in genetic alterations and pathology between ALS worms and patients, similar therapeutic strategies may eventually be valuable for ALS patients

    Comparison of two automatic cell-counting solutions for fluorescent microscopic images

    Get PDF
    Cell counting in microscopic images is one of the fundamental analysis tools in life sciences, but is usually tedious, time consuming and prone to human error. Several programs for automatic cell countinghavebeendeveloped sofar,butmostof them demand additional training or data input from the user. Most of them do not allow the users to online monitor the counting results, either. Therefore, we designed two straightforward, simple-to-use cell-counting programs that also allow users to correct the detection results. In this paper, we present the CELLCOUNTER and LEARN123 programs for automatic and semiautomatic counting of objects in fluorescent microscopic images (cells or cell nuclei) with a user-friendly interface. Although CELLCOUNTER is based on predefined and fine-tuned set of filters optimized on sets of chosen experiments, LEARN123 uses an evolutionary algorithm to determine the adapt filter parameters based on a learning set of images. CELLCOUNTER also includes an extension for analysis of overlaying images. The efficiency of both programs was assessed on images of cells stained with different fluorescent dyes by comparing automatically obtained results with results that were manually annotated by an expert. With both programs, the correlation between automatic and manual counting was very high (R2 < 0.9), although CELLCOUNTER had some difficulties processing images with no cells or weakly stained cells, where sometimes the background noise was recognized as an object of interest. Nevertheless, the differences between manual and automatic counting were small compared to variations between experimental repeats. Both programs significantly reduced the time required to process the acquired images from hours tominutes. The programs enable consistent, robust, fast and accurate detection of fluorescent objects and can therefore be applied to a range of different applications in different fields of life sciences where fluorescent labelling is used for quantification of various phenomena. Moreover, CELLCOUNTER overlay extension also enables fast analysis of related images thatwouldotherwise require imagemergingforaccurateanalysis, whereas LEARN123’s evolutionary algorithm can adapt counting parameters to specific sets of images of different experimental settings

    The NASA SBIR product catalog

    Get PDF
    The purpose of this catalog is to assist small business firms in making the community aware of products emerging from their efforts in the Small Business Innovation Research (SBIR) program. It contains descriptions of some products that have advanced into Phase 3 and others that are identified as prospective products. Both lists of products in this catalog are based on information supplied by NASA SBIR contractors in responding to an invitation to be represented in this document. Generally, all products suggested by the small firms were included in order to meet the goals of information exchange for SBIR results. Of the 444 SBIR contractors NASA queried, 137 provided information on 219 products. The catalog presents the product information in the technology areas listed in the table of contents. Within each area, the products are listed in alphabetical order by product name and are given identifying numbers. Also included is an alphabetical listing of the companies that have products described. This listing cross-references the product list and provides information on the business activity of each firm. In addition, there are three indexes: one a list of firms by states, one that lists the products according to NASA Centers that managed the SBIR projects, and one that lists the products by the relevant Technical Topics utilized in NASA's annual program solicitation under which each SBIR project was selected

    Diseño de un robot móvil autónomo de telepresencia

    Get PDF
    The recent rise in tele-operated autonomous mobile vehicles calls for a seamless control architecture that reduces the learning curve when the platform is functioning autonomously (without active supervisory control), as well as when tele-operated. Conventional robot plat-forms usually solve one of two problems. This work develops a mobile base using the Robot Operating System (ROS) middleware for teleoperation at low cost. The three-layer architec-ture introduced adds or removes operator complexity. The lowest layer provides mobility and robot awareness; the second layer provides usability; the upper layer provides inter-activity. A novel interactive control that combines operator intelligence/ skill with robot/autonomous intelligence enabling the mobile base to respond to expected events and ac-tively react to unexpected events is presented. The experiments conducted in the robot laboratory summarises the advantages of using such a system.El reciente auge de los vehículos móviles autónomos teleoperados exige una arquitectura de control sin fisuras que reduzca la curva de aprendizaje cuando la plataforma funciona de forma autónoma (sin control de supervisión activo), así como cuando es teleoperada. Las plataformas robóticas convencionales suelen resolver uno de los dos problemas. Este tra-bajo desarrolla una base móvil que utiliza el middleware Robot Operating System (ROS) para la teleoperación a bajo coste. La arquitectura de tres capas introducida añade o elimina la complejidad del operador. La capa más baja proporciona movilidad y conciencia robótica; la segunda capa proporciona usabilidad; la capa superior proporciona interactividad. Se presenta un novedoso control interactivo que combina la inteligencia/habilidades del op-erador con la inteligencia autónoma del robot, lo que permite que la base móvil responda a los eventos esperados y reaccione activamente a los eventos inesperados. Los experi-mentos realizados en el laboratorio robótica resumen las ventajas de utilizar un sistema de este tipoDepartamento de Ingeniería de Sistemas y AutomáticaMáster en Electrónica Industrial y Automátic

    Enhancing the museum experience with a sustainable solution based on contextual information obtained from an on-line analysis of users’ behaviour

    Get PDF
    Human computer interaction has evolved in the last years in order to enhance users’ experiences and provide more intuitive and usable systems. A major leap through in this scenario is obtained by embedding, in the physical environment, sensors capable of detecting and processing users’ context (position, pose, gaze, ...). Feeded by the so collected information flows, user interface paradigms may shift from stereotyped gestures on physical devices, to more direct and intuitive ones that reduce the semantic gap between the action and the corresponding system reaction or even anticipate the user’s needs, thus limiting the overall learning effort and increasing user satisfaction. In order to make this process effective, the context of the user (i.e. where s/he is, what is s/he doing, who s/he is, what are her/his preferences and also actual perception and needs) must be properly understood. While collecting data on some aspects can be easy, interpreting them all in a meaningful way in order to improve the overall user experience is much harder. This is more evident when we consider informal learning environments like museums, i.e. places that are designed to elicit visitor response towards the artifacts on display and the cultural themes proposed. In such a situation, in fact, the system should adapt to the attention paid by the user choosing the appropriate content for the user’s purposes, presenting an intuitive interface to navigate it. My research goal is focused on collecting, in a simple,unobtrusive, and sustainable way, contextual information about the visitors with the purpose of creating more engaging and personalized experiences

    NASA technology applications team: Applications of aerospace technology

    Get PDF
    Two critical aspects of the Applications Engineering Program were especially successful: commercializing products of Application Projects; and leveraging NASA funds for projects by developing cofunding from industry and other agencies. Results are presented in the following areas: the excimer laser was commercialized for clearing plaque in the arteries of patients with coronary artery disease; the ultrasound burn depth analysis technology is to be licensed and commercialized; a phased commercialization plan was submitted to NASA for the intracranial pressure monitor; the Flexible Agricultural Robotics Manipulator System (FARMS) is making progress in the development of sensors and a customized end effector for a roboticized greenhouse operation; a dual robot are controller was improved; a multisensor urodynamic pressure catherer was successful in clinical tests; commercial applications were examined for diamond like carbon coatings; further work was done on the multichannel flow cytometer; progress on the liquid airpack for fire fighters; a wind energy conversion device was tested in a low speed wind tunnel; and the Space Shuttle Thermal Protection System was reviewed

    Assessing motor-related phenotypes of Caenorhabditis elegans with the wide field-of-view nematode tracking platform

    Get PDF
    Caenorhabditis elegans is a valuable model organism in biomedical research that has led to major discoveries in the fields of neurodegeneration, cancer and aging. Because movement phenotypes are commonly used and represent strong indicators of C. elegans fitness, there is an increasing need to replace manual assessments of worm motility with automated measurements to increase throughput and minimize observer biases. Here, we provide a protocol for the implementation of the improved wide field-of-view nematode tracking platform (WF-NTP), which enables the simultaneous analysis of hundreds of worms with respect to multiple behavioral parameters. The protocol takes only a few hours to complete, excluding the time spent culturing C. elegans, and includes (i) experimental design and preparation of samples, (ii) data recording, (iii) software management with appropriate parameter choices and (iv) post-experimental data analysis. We compare the WF-NTP with other existing worm trackers, including those having high spatial resolution. The main benefits of WF-NTP relate to the high number of worms that can be assessed at the same time on a whole-plate basis and the number of phenotypes that can be screened for simultaneously
    • …
    corecore