Advanced flight control system study

A fly by wire flight control system architecture designed for high reliability includes spare sensor and computer elements to permit safe dispatch with failed elements, thereby reducing unscheduled maintenance. A methodology capable of demonstrating that the architecture does achieve the predicted performance characteristics consists of a hierarchy of activities ranging from analytical calculations of system reliability and formal methods of software verification to iron bird testing followed by flight evaluation. Interfacing this architecture to the Lockheed S-3A aircraft for flight test is discussed. This testbed vehicle can be expanded to support flight experiments in advanced aerodynamics, electromechanical actuators, secondary power systems, flight management, new displays, and air traffic control concepts

Modelling and Measurement of Charge Transfer in Multiple GEM Structures

Measurements and numerical simulations on the charge transfer in Gas Electron Multiplier (GEM) foils are presented and their implications for the usage of GEM foils in Time Projection Chambers are discussed. A small test chamber has been constructed and operated with up to three GEM foils. The charge transfer parameters derived from the electrical currents monitored during the irradiation with an Fe-55 source are compared with numerical simulations. The performance in magnetic fields up to 2 T is also investigated.Comment: 21 pages, 16 figures, submitted to NIM-

What Should A BBA Graduate Be Able To Do?: These Competencies Are Essential

University Schools of Business Administration are continually responding to the demands of stakeholders concerning the quality of the education embodied in the Bachelor of Business Administration degree.  This collaborative paper discusses the competencies that are considered essential from the viewpoint of four stakeholders:  accrediting agencies, faculty/administration, employers, and students/graduates.  The authors present and support their views on competencies—identifying, achieving, assessing, and maintaining currency—in preparing future business leaders.&nbsp

Characterisation of a track structure imaging detector

The spatial distribution of radiation-induced ionisations in sub-cellular structures plays an important role in the initial formation of radiation damage to biological tissues. Using the nanodosimetry approach, physical characteristics of the track structure can be measured and correlated to DNA damage. In this work, a novel nanodosimeter is presented, which detects positive ions produced by radiation interacting with a gas-sensitive volume in order to obtain a high resolution image of the radiation track structure. The characterisation of the detector prototype was performed and different configurations of the device were tested by varying the detector cathode material and the working gas. Preliminary results show that the ionisation cluster size distribution can be obtained with this approach. Further work is planned to improve the detector efficiency in order to register the complete three-dimensional track structure of ionising radiatio

Assessing Undergraduate Business Degree Outcomes: A Comparison Of Two Universities

The importance of outcomes assessment has produced innovative course developments and resulted in enhanced Capstone educational experiences for undergraduate students at both universities.  This collaborative paper compares the evolution and outcomes assessment of the Capstone business course as a fundamental component of the business curriculum, discusses initiatives to provide even greater educational opportunities for students, assessing effectively over the continuum, and keeping the courses current to the university and business environments

Feasibility-Seeking and Superiorization Algorithms Applied to Inverse Treatment Planning in Radiation Therapy

We apply the recently proposed superiorization methodology (SM) to the inverse planning problem in radiation therapy. The inverse planning problem is represented here as a constrained minimization problem of the total variation (TV) of the intensity vector over a large system of linear two-sided inequalities. The SM can be viewed conceptually as lying between feasibility-seeking for the constraints and full-fledged constrained minimization of the objective function subject to these constraints. It is based on the discovery that many feasibility-seeking algorithms (of the projection methods variety) are perturbation-resilient, and can be proactively steered toward a feasible solution of the constraints with a reduced, thus superiorized, but not necessarily minimal, objective function value.Comment: Contemporary Mathematics, accepted for publicatio

Uncovering Bugs in Distributed Storage Systems during Testing (not in Production!)

Testing distributed systems is challenging due to multiple sources of nondeterminism. Conventional testing techniques, such as unit, integration and stress testing, are ineffective in preventing serious but subtle bugs from reaching production. Formal techniques, such as TLA+, can only verify high-level specifications of systems at the level of logic-based models, and fall short of checking the actual executable code. In this paper, we present a new methodology for testing distributed systems. Our approach applies advanced systematic testing techniques to thoroughly check that the executable code adheres to its high-level specifications, which significantly improves coverage of important system behaviors. Our methodology has been applied to three distributed storage systems in the Microsoft Azure cloud computing platform. In the process, numerous bugs were identified, reproduced, confirmed and fixed. These bugs required a subtle combination of concurrency and failures, making them extremely difficult to find with conventional testing techniques. An important advantage of our approach is that a bug is uncovered in a small setting and witnessed by a full system trace, which dramatically increases the productivity of debugging

Final-Focus System for CLIC at 3 TeV

We describe a base-line optics for a 3-TeV final-focus system of the Compact Linear Collider (CLIC). The proposed system consists of an initial beta-matching region, two chromatic correction sections, and a final transformer, and it provides a total demagnification by a factor 90 horizontally and 346 vertically. The length per side amounts to 3.3 km. The effect of synchrotron radiation and higher-order aberrations is minimised by an odd dispersion function in the chromatic correction section. For a total flat energy spread of 1%, the system promises a luminosity of about 80% of the ideal. The 20-30% spot-size dilutions in the two transverse planes reflect a trade-off between the Oide effect and higher-order chromo-geometric aberrations

Instrumentation for measurement of cosmic noise at 0.75, 1.225 and 2.0 mc/s from a rocket final technical report

Amplitudes and phases of first harmonics of magnetic storm annual variation dependence on storm intensity and 11 year cycl