A generic operational simulation for early design civil unmanned aerial vehicles

Contemporary aerospace programmes often suffer from large cost overruns, delivery delays and inferior product quality. This is caused in part by poor predictive quality of the early design phase processes with regards to the operational environment of a product. This paper develops the idea of a generic operational simulation that can help designers to rigorously analyse and test their early product concepts. The simulation focusses on civil Unmanned Air Vehicle products and missions to keep the scope of work tractable. The research agenda is introduced along with ideas, initial results and future work. Designers specify details about their product, its environment and anticipated operational procedures. The simulation returns information that can help to estimate the value of the product using the value-driven design approach. Information will include recurring and non-recurring mission cost items. The research aim is to show that an operational simulation can improve early design concepts, thereby reducing delays and cost overruns. Moreover, a trade-off between mission fidelity and model generality is sought along with a generic ontology of civil Unmanned Air Vehicle missions and guidelines about capturing operational informatio

The Bottom Line Limitation to the Rule of \u3cem\u3eGriggs v. Duke Power Company\u3c/em\u3e

Part I of this article analyzes the background to the Teal decision and the treatment by the majority and dissent of the issue known in employment discrimination law as the bottom line limitation to the disparate impact theory of employment discrimination. Part II explains why, for reasons beyond those considered by the Teal majority, not only was the Court\u27s rejection of the bottom line theory manifestly correct, but a contrary result would have had grievous consequences. Part III then argues for a similar rejection of the bottom line limitation in those situations where most observers have taken for granted that the bottom line limitation would apply

Robust gas turbine and airframe system design in light of uncertain fuel and CO2 prices

This paper presents a study that numerically investigated which cruise speed the next generation of short-haul aircraft with 150 seats should fly at and whether a conventional two- or three-shaft turbofan, a geared turbofan, a turboprop, or an open rotor should be employed in order to make the aircraft's direct operating cost robust to uncertain fuel and carbon (CO2) prices in the Year 2030, taking the aircraft productivity, the passenger value of time, and the modal shift into account. To answer this question, an optimization loop was set up in MATLAB consisting of nine modules covering gas turbine and airframe design and performance, flight and aircraft fleet simulation, operating cost, and optimization. If the passenger value of time is included, the most robust aircraft design is powered by geared turbofan engines and cruises at Mach 0.80. If the value of time is ignored, however, then a turboprop aircraft flying at Mach 0.70 is the optimum solution. This demonstrates that the most fuel-efficient option, the open rotor, is not automatically the most cost-efficient solution because of the relatively high engine and airframe costs

Value driven conceptual design of Unmanned Air System for defence applications

The work presented concerns the development of a value driven conceptual design assessment framework for a small Unmanned Air System (UAS) to be utilized in a defence application. In the field of Multi-Disciplinary Design Optimization, most recent systematic search has been devoted to fixed topology parametric geometries, pertaining to a single concept, with very little stress put on the optimization of variable topologies describing alternative design concepts. The search is conducted in a highly novel manner, generating a broad range of combinations of UAS configurations and geometries by systematically searching alternative concepts and design configurations through the parameterization of the aircraft geometric topologies. Moreover, the “value” of proposed solutions is assessed in an objective way both from performance and economic perspectives, while the optimal solution is identified after relaxing all of the design constraints as advocated by value driven design philosophy. During the multi-criteria decision analysis, the quantification/conversion of the linguistic preferences of the user between the various attributes to numerical values has disclosed some deficiencies introduced by the unjustifiable numerical scales used in the Analytic Hierarchy Process (AHP). This problem is resolved by a novel value model synthesizing the AHP assessment methodologies with multi-attribute value-focused analysis

Value driven conceptual design of unmanned air system for a defence application

The work presented culminates in the development of a value driven conceptual design assessment framework for a small Unmanned Air System (UAS) to be utilized in a defence application. In the field of Multi-Disciplinary Design Optimisation, most recent systematic search has been devoted to fixed topology parametric geometries, pertaining to a single concept, with very little stress put on the optimization of variable topologies describing alternative design concepts. The search is conducted in a highly novel manner, generating a broad range of combinations of UAS configurations and geometries by systematically searching alternative concepts and design configurations through the parameterization of the aircraft geometric topologies. Moreover, the “value” of proposed solutions is assessed in an objective way both from performance and economic perspectives, while the optimal solution is identified based on the user’s needs after relaxing all of the design constraints. During the multi-criteria decision analysis, the quantification/conversion of the linguistic preferences of the user between the various attributes to numerical values has disclosed some deficiencies introduced by the unjustifiable numerical scales used in the Analytic Hierarchy Process (AHP) and a novel value model for consistent value assessment is introduced, synthesizing the AHP assessment methodologies with multi-attribute value-focused analysis

Health Claims Arbitration in Maryland: The Experiment Has Failed

The authors note that Maryland\u27s system for health claims arbitration has failed to reduce the number of malpractice suits, the size of damages awards, or the delay in resolving these claims. After reviewing the current system, its strengths and weaknesses, and various proposals to remedy its problems by amending the current legislation, the authors advance their own suggestions for amending Maryland\u27s health claims arbitration legislation

The Mini-Cog as a Screen for Dementia: Validation in a Population-Based Sample

To test the Mini-Cog, a brief cognitive screening test, in an epidemiological study of dementia in older Americans. Design : A population-based post hoc examination of the sensitivity and specificity of the Mini-Cog for detecting dementia in an existing data set. Setting : The Monongahela Valley in Western Pennsylvania. Participants : A random sample of 1,119 older adults enrolled in the Monongahela Valley Independent Elders Survey (MoVIES). Measurements : The effectiveness of the Mini-Cog in detecting independently diagnosed dementia was compared with that of the Mini-Mental State Examination (MMSE) and a standardized neuropsychological battery. Results : The Mini-Cog, scored by an algorithm as “possibly impaired” or “probably normal,” and the MMSE, at a cutpoint of 25, had similar sensitivity (76% vs 79%) and specificity (89% vs 88%) for dementia, comparable with that achieved using a conventional neuropsychological battery (75% sensitivity, 90% specificity). Conclusion : When applied post hoc to an existing population, the Mini-Cog was as effective in detecting dementia as longer screening and assessment instruments. Its brevity is a distinct advantage when the goal is to improve identification of older adults in a population who may be cognitively impaired. Prior evidence of good performance in a multiethnic community-based sample further supports its validity in the ethnolinguistically diverse populations of the United States in which widely used cognitive screens often fail.Peer Reviewedhttp://deepblue.lib.umich.edu/bitstream/2027.42/65703/1/j.1532-5415.2003.51465.x.pd

What\u27s in a Kiss

Title with red borderhttps://scholarsjunction.msstate.edu/cht-sheet-music/2440/thumbnail.jp

Coats’ disease in Tanzania: first case report and literature review

Background:Coats’ disease is an exudative retinal detachment with vascular telangiectasis occurring mostly in male children, the age group most affected by retinoblastoma.Objectives:To compare the differential diagnoses of Coats’ disease. To establish recommendation to early disease detection.Materials and Methods:A 3-year-old female child was referred to Muhimbili National Hospital (MNH), Tanzania, in September 2011. She had presented at the peripheral hospital with gradual onset of left eye leukocoria for 1 year and pain for 2 months. B-scan showed a mass in the left eye. A clinical diagnosis of retinoblastoma was made. Left eye enucleation was performed; the patient was referred to MNH, with the enucleated specimen.Results:Brain and orbits scan revealed no residual tumour. The globe measured 2x1.8 cm, the optic nerve stump measured 3 mm. A whitish mass filled the vitreous, with complete retinal detachment. Microscopy showed retinal gliosis, detachment with sub retinal PAS positive exudates, vacuolation and cholesterol clefts. Foreign body giant cells were present; telangiectatic thin-walled blood vessels were identified. Clinico-pathological findings were of stage 4 Coats’ disease.Conclusion:Coats’ disease is an important differential diagnosis of retinoblastoma. Delay to detect Coats’ disease leads to vision loss which necessitates eye enucleation as was in this child.Keywords: Coats’ disease, Tanzani