9,310 research outputs found
Integrating testing techniques through process programming
Integration of multiple testing techniques is required to demonstrate high quality of software. Technique integration has three basic goals: incremental testing capabilities, extensive error detection, and cost-effective application. We are experimenting with the use of process programming as a mechanism of integrating testing techniques. Having set out to integrate DATA FLOW testing and RELAY, we proposed synergistic use of these techniques to achieve all three goals. We developed a testing process program much as we would develop a software product from requirements through design to implementation and evaluation. We found process programming to be effective for explicitly integrating the techniques and achieving the desired synergism. Used in this way, process programming also mitigates many of the other problems that plague testing in the software development process
Elastic suspension of a wind tunnel test section
Experimental verification of the theory describing arbitrary motions of an airfoil is reported. The experimental apparatus is described. A mechanism was designed to provide two separate degrees of freedom without friction or backlash to mask the small but important aerodynamic effects of interest
Caging Mechanism for a drag-free satellite position sensor
A disturbance compensation system for satellites based on the drag-free concept was mechanized and flown, using a spherical proof mass and a cam-guided caging mechanism. The caging mechanism controls the location of the proof mass for testing and constrains it during launch. Design requirements, design details, and hardware are described
To perform a gyro test of general relativity in a satellite and develop associated control technology
Performance tests of gyroscope operations and gyroscope readout equipment are discussed. The gyroscope was tested for 400 hours at liquid helium temperatures with spin speeds up to 30 Hz. Readout by observing trapped magnetic flux in the spinning rotor with a sensitive magnetometer was accomplished. Application of the gyroscope to space probes and shuttle vehicles
Study to develop gradiometer techniques
The primary goal of the current gravity gradiometer research at Stanford has been to establish the feasibility of using a gravity gradiometer with 1 E accuracy, as the primary sensor in various applications. The two applications considered here in detail are geodesy missions and inertial navigation systems. Preliminary sections on gravity models and gravity gradiometer bias estimation are also included
Evaluation of prototype Advanced Life Support (ALS) pack for use by the Health Maintenance Facility (HMF) on Space Station Freedom (SSF)
The purpose is to evaluate the prototype Advanced Life Support (ALS) Pack which was developed for the Health Maintenance Facility (HMF). This pack will enable the Crew Medical Officer (CMO) to have ready access to advanced life support supplies and equipment for time critical responses to any situation within the Space Station Freedom. The objectives are: (1) to evaluate the design of the pack; and (2) to collect comments for revision to the design of the pack. The in-flight test procedures and other aspects of the KC-135 parabolic test flight to simulate weightlessness are presented
Develop minimum thrustor control laws and select orbits for a geodesy drag-free satellite
The original motivation for studying control laws for pulse plasma systems was based on the improved life characteristics possible with pulse plasma jets. These pulse plasma units are relatively massive compared with cold gas thrustors. As a result, therefore, significant mass savings can be achieved by minimizing the the number of thrustors. The control laws, therefore, were developed for thrust available from two thrustors only. In a spinning satellite, these thrustors are sufficient to completely control the vehicle as long as the spin rate is sufficiently high for a given level of external disturbance. The thrustors are canted so that a component of each is along the plus and minus spin axis. The other component of each thrustor acts in the radial direction. It is sufficient to analyze the behavior in the plane of spin assuming a single thrustor
On the applicability of integrated circuit technology to general aviation orientation estimation
The criteria of the significant value of the panel instruments used in general aviation were examined and kinematic equations were added for comparison. An instrument survey was performed to establish the present state of the art in linear and angular accelerometers, pressure transducers, and magnetometers. A very preliminary evaluation was done of the computers available for data evaluation and estimator mechanization. The mathematical model of a light twin aircraft employed in the evaluation was documented, the results of the sensor survey and the results of the design studies were presented
Strategies for Hope and Sustainability, The Beginning Principal: needs and challenges
Since the 1990s, educational leaders in developed countries have experienced significant change across all educational systems. To date, this momentum for rapid change has continued unabated. Political pressures on schools continue to increase as short term governments expect improvements in educational outcomes in shortened periods of time. Public expectations of performance by schools are intensifying. School effectiveness dominates professional discourse. Learning technologies have expanded. Family contexts have changed and the nature of the educational workforce is dictated by society s economic and social situation. Catholic school principals, in addition to coping with such issues, are also regarded as leaders within the Catholic Church. The religious dimension of their leadership role requires significant faith-based grounding and knowledge about the Church in order to carry out their duties and responsibilities. For beginning principals in Catholic schools, their role is even more complex, demanding and challenging. They not only have to negotiate all the demands placed on them as Catholic school leaders, they also have to grapple with the newness of the role. This paper presents findings from a qualitative research study seeking to identify the professional and personal needs of newly appointed principals in Catholic education in Western Australia
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