48,745 research outputs found

    Control power requirements of VTOL aircraft Quarterly status report, 1 Apr. - 30 Jun. 1969

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    Computer derived reference design of intercity VTOL aircraft and analysis of control power requirements and operating cost

    Simplified Model of Segmented Electrode Losses in Nonequilibrium MHD Generators

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    Simplified model of segmented electrode losses in nonequilibrium magnetohydrodynamic generator

    Wind energy system time-domain (WEST) analyzers

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    A portable analyzer which simulates in real time the complex nonlinear dynamics of horizontal axis wind energy systems was constructed. Math models for an aeroelastic rotor featuring nonlinear aerodynamic and inertial terms were implemented with high speed digital controllers and analog calculation. This model was combined with other math models of elastic supports, control systems, a power train and gimballed rotor kinematics. A stroboscopic display system graphically depicting distributed blade loads, motion, and other aerodynamic functions on a cathode ray tube is included. Limited correlation efforts showed good comparison between the results of this analyzer and other sophisticated digital simulations. The digital simulation results were successfully correlated with test data

    Brown-Tail Moth, \u3ci\u3eEuproctis Chrysorrhoea,\u3c/i\u3e an Indigenous Pest of Parks and Public in the Benelux Countries (Lepidoptera: Lymantriidae)

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    Euproctis chrysorrhoea is a pest of park and shade trees and of the public in the Benelux countries as well as in the northeastern United States and Canada. In the Benelux countries the brown-tail moth is present every year in the dune regions, where it mainly feeds on Hippophae rhamnoides. Hairs from the larvae are irritating to the human skin producing a papular urticaria. An outbreak of the caterpillars produced widespread discomfort at a beach in the Netherlands in 1982 following defoliation of food plants and migration of the larvae seeking food, with resulting human contact, as well as wind dispersal of the hairs

    Aerial Vehicle Tracking by Adaptive Fusion of Hyperspectral Likelihood Maps

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    Hyperspectral cameras can provide unique spectral signatures for consistently distinguishing materials that can be used to solve surveillance tasks. In this paper, we propose a novel real-time hyperspectral likelihood maps-aided tracking method (HLT) inspired by an adaptive hyperspectral sensor. A moving object tracking system generally consists of registration, object detection, and tracking modules. We focus on the target detection part and remove the necessity to build any offline classifiers and tune a large amount of hyperparameters, instead learning a generative target model in an online manner for hyperspectral channels ranging from visible to infrared wavelengths. The key idea is that, our adaptive fusion method can combine likelihood maps from multiple bands of hyperspectral imagery into one single more distinctive representation increasing the margin between mean value of foreground and background pixels in the fused map. Experimental results show that the HLT not only outperforms all established fusion methods but is on par with the current state-of-the-art hyperspectral target tracking frameworks.Comment: Accepted at the International Conference on Computer Vision and Pattern Recognition Workshops, 201

    Problem Bank Resolution: Evaluating the Options

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    The authors describe the function of intermediation in the financial sector and the role of regulatory supervision in managing the inherent structural vulnerability of the process. Financial intermediaries provide both a risk taking and a maturity transformation function in mobilizing savings assets into productive real investments. These inherent activities create a natural structural vulnerability which regulatory oversight is intended to mitigate. The consequence of failure to effectively manage the inherent structural vulnerability can lead to "runs" in which depositors withdraw funds leading to institutional insolvency. The vulnerability to runs becomes a public policy concern when a loss of confidence in the sector leads to a contagious loss of confidence in other institutions. In response to these dangers, governments and regulators throughout the world have established "financial safety nets" to be triggered at various stages in evolving financial crises. The "safety nets" can be seen as comprising at least seven elements or separate stages in managing financial crises: 1) the chartering function screens out institution managers who would be likely to take on excessive insolvency exposure; 2) if institution managers do try to expose their institution to shocks, the prudential supervision function is established to prevent this; 3) if a shock still occurs, the termination authority removes the institution's license before too much damage is caused; 4) if losses still occur, the insurance function may prevent creditors from running; 5) if the institution closes, the insurance function may sustain the confidence of creditors at similar institutions; 6) if runs take place at other institutions, the lender of last resort function may help solvent institutions meet the claims of liability holders; and 7) if other failures occur the monetary authority may confine the damage to the institutions directly affected. The role of regulators is to return the financial structure to its position before the crisis and restore confidence in the system and should not be punitive or involve reconstruction of the system, which can wait until a later time. Solutions will differ depending on how many institutions are affected and whether the problem affects impacts on the entire system or market. There are three generic options available for problem resolution: 1) permitting continued operation under some restrictions; 2) forcing a merger with another institutions or 3) closure of some form. Within these three options are seven ways to either continue operations, force a merger or liquidate. These are: 1) forbearance - granting of time for an institution to resolve its problems; 2) capital infusion with existing management; 3) regulatory control (temporary); 4) de facto nationalization of the institutions; 5) Good-bank, Bad-bank split; 6) purchases and assumption; 7) liquidation with and without governmental assistance. The authors review and summarize the experiences in the US, Scandinavia and France where a variety of these resolution options have been recently applied. Forbearance was used in an attempt to resolve the US Thrift Crisis of the 1980s. This option did not create the desired results and the Resolution Trust Corporation was established in 1989 in order to organize the process. When Norway was faced with a major banking crisis in 1991, it nationalized the banking system. Sweden similarly infused its failing banks with capital during a crisis in 1993, effectively nationalizing them. The "good bank-bad bank" method was used extensively in the Swedish bailout. Finland's central bank took over failing banks in 1991 and the remaining ones were consolidated into one entity. The French government has bailed out troubled Credit Lyonnais, costing the government as much as 135 billion francs. From their review of foreign intervention in bank crises, the authors conclude that: 1) Costs of intervention are generally larger than anticipated; 2) Interventions aimed at preserving the current institutional structure generally do not achieve the expected outcome; and 3) The only true resolution appears to come from a change in the aggregate economy.
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