33,821 research outputs found
Qualitative evaluation of a conformal velocity vector display for use at high angles-of-attack in fighter aircraft
A piloted simulation study was conducted to evaluate the utility of a display device designed to illustrate graphically and conformally the approximate location of a fighter aircraft's velocity vector. The display device consisted of two vertical rows of light emitting diodes (LED's) located toward the center of the cockpit instrument panel to each side of the control stick. The light strings provided a logical extension of the head up display (HUD) velocity vector symbol at flight path angles which exceeded the HUD field-of-view. Four test subjects flew a modified F/A-18 model with this display in an air-to-air engagement task against an equally capable opponent. Their responses to a questionnaire indicated that the conformal velocity vector information could not be used during the scenarios investigated due to the inability to visually track a target and view the lights simultaneously
Desertification indicators for the European Mediterranean region: state of the art and possible methodological approaches [= Indicatori di desertificazione per il Mediterraneo europeo: stato dell'arte e proposte di metodo]
The Italian Environment Protection Agency (ANPA), and the Desertification Research
Centre at the University of Sassary have worked jointly to provide decision-makers
with an in-depth analysis of the state of the art and methodologies applicable to the
evaluation of the desertification phenomenon.
ANPA has promoted this important research activity, within the wider and more
dynamic framework of actions it conducts in the Italian National Committee,
providing its support to the definition and start up of the National Plan to Combat
Desertification and Drought.
The complexity of the phenomena and their causes leads to the individuation of a
plurality of “actors” who might take the responsibility to carry out actions aimed at
combating Desertification and Drought.
Indicators represent a crucial link in the chain that, from knowledge, leads to taking
decisions and promoting responsible behaviours: starting from an evaluation of the
various, physical, biologic, socio-economic processes that contribute to land
degradation and desertification, the goal is to individuate indicators that might prove
useful in territorial planning and public information activities, and that might be a
suitable answer to the request for direct knowledge of the status and evolution of the
phenomenon, as well as the opportunity to take actions aimed at mitigating and,
above all, preventing the occurrence of the phenomenon
A review of US Army aircrew-aircraft integration research programs
If the U.S. Army's desire to develop a one crew version of the Light Helicopter Family (LHX) helicopter is to be realized, both flightpath management and mission management will have to be performed by one crew. Flightpath management, the helicopter pilot, and the handling qualities of the helicopter were discussed. In addition, mission management, the helicopter pilot, and pilot control/display interface were considered. Aircrew-aircraft integration plans and programs were reviewed
Dynamic model of optimized supply for organizational units of armed forces (at decentralized procurement)
Efficient activity of organizational units in armed forces is impossible without comprehensive and continuous logistics. The key role in the arrangement of logistics is played by supply processes: ordering, purchase, delivery, and storage of material and technical resources (goods). The Complexity and multiplicity of implementing the logistics process assume the use of economic-mathematical modeling, as an efficient tool for supporting decisions, which ensures the selection of the most favorable supply options. This paper provides a dynamic model of optimized supply (at decentralized procurement of material and technical resources), which describes the possible options of arranging the logistics of organizational units of the armed forces. The criterion of global optimization is represented by a normalized performance indicator characterizing the level of provision of organizational units with material and technical resources. The proposed economic-mathematical model is an efficient tool for supporting decisions taken by logistics-management divisions of organizational units of armed forces – at multiple options of implementing the logistic processes and limited financial resources, which allows optimizing the level of provision of organizational units with required material and technical resources (for the entire planning period of supply, regarding change of needs, scope of funds allocated for logistics and logistic costs accompanying the supply process)
Decision Aids for Airborne Intercept Operations in Advanced Aircrafts
A tactical decision aid (TDA) for the F-14 aircrew, i.e., the naval flight officer and pilot, in conducting a multitarget attack during the performance of a Combat Air Patrol (CAP) role is presented. The TDA employs hierarchical multiattribute utility models for characterizing mission objectives in operationally measurable terms, rule based AI-models for tactical posture selection, and fast time simulation for maneuver consequence prediction. The TDA makes aspect maneuver recommendations, selects and displays the optimum mission posture, evaluates attackable and potentially attackable subsets, and recommends the 'best' attackable subset along with the required course perturbation
A Study on the Noise Threshold of Fault-tolerant Quantum Error Correction
Quantum circuits implementing fault-tolerant quantum error correction (QEC)
for the three qubit bit-flip code and five-qubit code are studied. To describe
the effect of noise, we apply a model based on a generalized effective
Hamiltonian where the system-environment interactions are taken into account by
including stochastic fluctuating terms in the system Hamiltonian. This noise
model enables us to investigate the effect of noise in quantum circuits under
realistic device conditions and avoid strong assumptions such as maximal
parallelism and weak storage errors. Noise thresholds of the QEC codes are
calculated. In addition, the effects of imprecision in projective measurements,
collective bath, fault-tolerant repetition protocols, and level of parallelism
in circuit constructions on the threshold values are also studied with emphasis
on determining the optimal design for the fault-tolerant QEC circuit. These
results provide insights into the fault-tolerant QEC process as well as useful
information for designing the optimal fault-tolerant QEC circuit for particular
physical implementation of quantum computer.Comment: 9 pages, 9 figures; to be submitted to Phys. Rev.
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