180 research outputs found

    Proceedings of the NSSDC Conference on Mass Storage Systems and Technologies for Space and Earth Science Applications

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    The proceedings of the National Space Science Data Center Conference on Mass Storage Systems and Technologies for Space and Earth Science Applications held July 23 through 25, 1991 at the NASA/Goddard Space Flight Center are presented. The program includes a keynote address, invited technical papers, and selected technical presentations to provide a broad forum for the discussion of a number of important issues in the field of mass storage systems. Topics include magnetic disk and tape technologies, optical disk and tape, software storage and file management systems, and experiences with the use of a large, distributed storage system. The technical presentations describe integrated mass storage systems that are expected to be available commercially. Also included is a series of presentations from Federal Government organizations and research institutions covering their mass storage requirements for the 1990's

    NSSDC Conference on Mass Storage Systems and Technologies for Space and Earth Science Applications, volume 1

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    Papers and viewgraphs from the conference are presented. This conference served as a broad forum for the discussion of a number of important issues in the field of mass storage systems. Topics include magnetic disk and tape technologies, optical disks and tape, software storage and file management systems, and experiences with the use of a large, distributed storage system. The technical presentations describe, among other things, integrated mass storage systems that are expected to be available commercially. Also included is a series of presentations from Federal Government organizations and research institutions covering their mass storage requirements for the 1990's

    Enterprise storage report for the 1990's

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    Data processing has become an increasingly vital function, if not the most vital function, in most businesses today. No longer only a mainframe domain, the data processing enterprise also includes the midrange and workstation platforms, either local or remote. This expanded view of the enterprise has encouraged more and more businesses to take a strategic, long-range view of information management rather than the short-term tactical approaches of the past. Some of the significant aspects of data storage in the enterprise for the 1990's are highlighted

    Dynamics Simulation and Optimal Control of a Multiple-input and Multiple-output Balancing Cube

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    This thesis document outlines the development of a multibody dynamics simulation of an actively stabilized multiple-input, multiple-output, coupled, balancing cube and the process of verifying the results by implementing the control algorithm in hardware. A non-linear simulation of the system was created in Simscape and used to develop a Linear Quadratic Gaussian control algorithm. To implement this algorithm in actual hardware, the system was first designed, manufactured, and assembled. The structure of the cube and the reaction wheels were milled from aluminum. DC brushless motors were installed into the mechanical system. In terms of electronics, a processor, orientation sensor, motor drivers, analog to digital converters, and a pulse width modulation board were assembled into the cube. Upon completion, the software to control the cube was developed using Simulink and run on a Raspberry Pi computer within the mechanism

    Identification and control of DC motors

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    This work has two main objectives: the first one is identify the model of DC motors - using various techniques from experimental data; Secondly, we want to design appropriate control structures for this system, so as to meet the specifications requested. The second chapter describes the equipment with which we work throughout the project, consisting of two rotary brushed DC motors provided by the company Ingenia Motion Control. The third chapter describes various techniques of system identification that are used to characterize the motor dynamics, and applied to the motors provided by the company Ingenia Motion Control. And the final chapter covers the design of controllers plants based on the specification in bandwidth, and provides detailed structures of PID control and I-PD control. This master thesis has been developed in the Institut de Robòtica i Informàtica Industrial (IRI) and in the company Ingenia Motion Control in the Firmware Division with the supervision of Vicenç Puig as director and Roger Juanpere and Rob Verhaart as advisers from the company

    High Availability and Scalability of Mainframe Environments using System z and z/OS as example

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    Mainframe computers are the backbone of industrial and commercial computing, hosting the most relevant and critical data of businesses. One of the most important mainframe environments is IBM System z with the operating system z/OS. This book introduces mainframe technology of System z and z/OS with respect to high availability and scalability. It highlights their presence on different levels within the hardware and software stack to satisfy the needs for large IT organizations

    Building a COTS archive for satellite data

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    The goal of the NOAA/NESDIS Active Archive was to provide a method of access to an online archive of satellite data. The archive had to manage and store the data, let users interrogate the archive, and allow users to retrieve data from the archive. Practical issues of the system design such as implementation time, cost and operational support were examined in addition to the technical issues. There was a fixed window of opportunity to create an operational system, along with budget and staffing constraints. Therefore, the technical solution had to be designed and implemented subject to constraint imposed by the practical issues. The NOAA/NESDIS Active Archive came online in July of 1994, meeting all of its original objectives

    Controller design of a robotic orthosis using sinusoidal-input describing function model

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    Stroke is one of top leading causes of death in the world and it happens to more than 15 million people yearly. According to the National Stroke Association of Malaysia (NASAM), stroke is the third leading cause of death in Malaysia with around 40,000 cases reported annually. Forty percent of stroke survivors suffer from movement impairments after stroke. My grandfather was one of the victims and he was unable to attend any rehabilitation sessions due to several reasons. Hence, he lost the golden time to regain his movement and freedom. There are a lot of similar cases that happen daily in Malaysia. Besides, as the number of stroke patients increases yearly, the need for physiotherapists or rehabilitation machines equally increases. Hence, a low-cost clinical rehabilitation device is essential to provide assistance for an effective rehabilitation program and substitute the conventional method, as well as to reduce the burden of physiotherapists. In future, the proposed rehabilitation device would benefit not only stroke patients, but any patients who lost their normal walking ability including post-accident patients or those who suffer from spinal cord injury. The rehabilitation device aims to provide training assistance to patients not only in rehabilitation centres but also at home for daily training. The robotic orthosis is planned to be configured based on moving joint angles of human lower extremities. In the first stage of this research, angle-time characteristics for knee and hip swinging motion are utilised as a sagittal motion reference for the rehabilitation devices. The aim of following a proper gait cycle during rehabilitation training is to train patients to perform standing and swinging phases at proper timing and simultaneously provide the correct position reference to the patient during rehabilitation training. This can prevent patients from walking abnormally with an asymmetric gait cycle along or after the rehabilitation program. Besides, various limitations and the bulky structure of other rehabilitation devices lead to the design of the two-link lower limb rehabilitation device. This project aims to develop an assistive robotic rehabilitation device that generates a human gait trajectory for hemiplegic stroke patient gait rehabilitation in future. The shortcomings of other control applications due to environmental conditions and disturbances lead to the implementation of the describing function approach in the development of the devices. A sinusoidal-input describing function (SIDF) approach was implemented to linearize the nonlinear robotic orthosis with linear transfer function. The reason for utilising the SIDF approach is due to the nonlinear actual plant model with the present of load torque disturbances, discontinuous nonlinearities such as saturation and backlash, and also multivariable in the system. The nonlinear properties of the plant were proven in the preliminary stage of the research. A conventional controller, PID control combined with position and trajectory inputs were also applied to the system in the early stage of research. However, the experimental results were not satisfying. Finally, the SIDF approach was chosen to linearize the nonlinear system. Hence, generating a controller is much easier with a linear model of the nonlinear system. A SIDF approach was implemented to generate a controller for the multivariable, nonlinear closed loop system. Firstly, the SIDF approach enables the determination of the linear function of the nonlinear model known as the SIDF model. By utilising the linear model to mimic the behaviour of the nonlinear rehabilitation system, the controller for the nonlinear plant was able to be generated. In this research a controller based on linear control theory technique was used. The MATLAB library was used to design the lead-lag controller for the rehabilitation device. Various simulations such as step responses, tracking and decoupling of both links were performed on the generated controller with the nonlinear model to study the capability of the controller. Besides that, real life experiment testing was carried out to validate the feasibility of the controller designed via the SIDF approach. Simulation and experimental results were obtained, compared, and discussed. The highly accurate responses gained from experimental setup showed the robustness of the controller generated via SIDF approach. The implementation of the SIDF approach in a rehabilitation device (vertical two-link manipulator) is a first and hence, fulfils a novelty requirement for this research

    EMPLOYEE TRANSCENDENCE AND PERFORMANCE OF HOTELS IN SOUTH-SOUTH, NIGERIA

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    This research centred on investigating the relationship between transcendence, as a dimension of the emerging theme of spiritual intelligence and employee performance in 3- and 4-star hotels in the South-South of Nigeria. The research focused on a total of 3 objectives addressing the relationship between transcendence and employee performance measures such as contextual, task and adaptive performance. Data were obtained from 234 staff from 36, hotels using the questionnaire. Reliability tests for the instruments yielded positive and substantial alpha coefficients (where α > 0.70). Correlation analysis was carried out using Spearman’s Rank Order Correlation tool, and the test showed that transcendence significantly contributes toward outcomes of the task, contextual and adaptive performance, hence, all null hypotheses were rejected. It was affirmed that transcendence plays a key role in the extent to which employees are able to carry out their routine tasks, build relationships with significant others and also learn effectively. It was thereafter recommended that the management of the 3- and 4-star hotels in the South-South geographical region of Nigeria should focus on developing and advancing favourable work environment which is conducive to workers’ engagement in spirituality and their development of spiritual intelligence particularly in the area of transcendence.  Article visualizations
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