Journal articles on the topic 'Airplanes Fuel systems'

Optimized electric motors are lighter and smaller than conventional piston engines. As a result, new airplane configurations are feasible as motors can be placed in unconventional positions. Through careful aircraft design higher aerodynamic efficiencies of airframe, propeller, and propeller integration can be achieved. The energy density of current batteries, however, still limits strongly the range of purely battery powered aircraft. But if the energy is stored in liquid fuel and converted by a generator into electric energy, then the advantages of electric propelled airplanes and conventional combustion engines can be combined. But which combustion engine is optimal for such a serial-hybrid electric aircraft? In this new propulsion chain, other boundary conditions apply to the combustion engine than in conventional aircraft designs. These boundary conditions interact with the characteristics of combustion engines. An example for an engine characteristic is that different kinds of piston engines exist. It can be observed that technologies, which result in lighter piston engines, are associated with lower efficiencies and vice versa. In this paper it will be shown through considerations on aircraft level, that the optimal combustion engine for an electric-hybrid airplane should be heavier and more efficient than the optimal combustion engine for a conventional aircraft.

In order to start performance testing and experimental research for enclosure of airplanes’ fuel systems, a type of integrative testing system is designed in this paper. This system can accomplish function and performance tests for enclosures in airplanes’ fuel system, and also can execute troubleshooting experiments.

The unmanned aircraft systems application is in the initial stage, which is characterized by a significant level of unmanned aircraft development and its elements, and by the lack of the basis of unmanned aircraft application in real technological processes. Resolution of this contradiction requires the solution of diverse problems of conceptual, technical, technological, methodological, organizational and legal – normative character.In general, today the unmanned aircraft systems application in the civil field is practically limited by particular cases of local applications in favor of the solution of current production or economic problems, mainly by the experimental procedure. Therefore, the market growth of the unmanned aircraft systems is expected providing the capability of a number of technical and administrative barriers that restrict the use of unmanned aircraft systems in the national airspace. It should also be noted the increasing prevalence of unmanned systems in general transport.This study was motivated by the globally increasing interest in unmanned cargo drones. It was focused particularly on cargo drones based on existing conventional general aviation airplanes and it should be regarded as a preliminary step towards the complex assessment of unmanned cargo aircraft transport systems. The aim was to estimate the fuel efficiency of such drones and to outline the optimums of some of their key design characteristics. A sample of 26 very light and light aircraft, and motorgliders was examined. The data was taken from open sources. The results outline that for best fuel economy the cargo drone should be a composite structure, piston engine airplane with wing aspect ratio of 10 to 12. Fuel efficiency estimation at distances of 500 to 2500 km shows that such cargo drones would be competitive with large piloted commercial cargo airplanes as well as with the road transport.

Abstract This paper describes assumptions, goals, methods, results and conclusions related to fuel tank arrangement of a flying wing passenger airplane configuration. A short overview of various fuel tank systems in use today of different types of aircraft is treated as a starting point for designing a fuel tank system to be used on very large passenger airplanes. These systems may be used to move fuel around the aircraft to keep the centre of gravity within acceptable limits, to maintain pitch and lateral balance and stability. With increasing aircraft speed, the centre of lift moves aft, and for trimming the elevator or trimmer must be used thereby increasing aircraft drag. To avoid this, the centre of gravity can be shifted by pumping fuel from forward to aft tanks. The lesson learnt from this is applied to minimise trim drag by moving the fuel along the airplane. Such a task can be done within coming days if we know the minimum drag versus CG position and weight value. The main part of the paper is devoted to wing bending moment distribution. A number of arrangements of fuel in airplane tanks are investigated and a scenario of refuelling - minimising the root bending moments - is presented. These results were obtained under the assumption that aircraft is in long range flight (14 hours), CL is constant and equal to 0.279, Specific Fuel Consumption is also constant and that overall fuel consumption is equal to 20 tons per 1 hour. It was found that the average stress level in wing structure is lower if refuelling starts from fuel tanks located closer to longitudinal plane of symmetry. It can influence the rate of fatigue.

With the aim of increasing the efficiency of maintenance and fuel usage in airplanes, structural health monitoring (SHM) of critical composite structures is increasingly expected and required. The optimized usage of this concept is subject of intensive work in the framework of the EU COST Action CA18203 “Optimising Design for Inspection” (ODIN). In this context, a thorough review of a broad range of energy harvesting (EH) technologies to be potentially used as power sources for the acoustic emission and guided wave propagation sensors of the considered SHM systems, as well as for the respective data elaboration and wireless communication modules, is provided in this work. EH devices based on the usage of kinetic energy, thermal gradients, solar radiation, airflow, and other viable energy sources, proposed so far in the literature, are thus described with a critical review of the respective specific power levels, of their potential placement on airplanes, as well as the consequently necessary power management architectures. The guidelines provided for the selection of the most appropriate EH and power management technologies create the preconditions to develop a new class of autonomous sensor nodes for the in-process, non-destructive SHM of airplane components.

Financial and environmental considerations continue to encourage aircraft manufacturers to consider alternate forms of aircraft propulsion. On the financial end, it is the continued rise in aviation fuel prices, as a result of an increasing demand for air travel, and the depletion of fossil fuel resources; on the environmental end, it is concerns related to air pollution and global warming. New aircraft designs are being proposed using electrical and hybrid propulsion systems, as a way of tackling both the financial and environmental challenges associated with the continued use of fossil fuels. While battery capabilities are evolving rapidly, the current state-of-the-art offers an energy density of ~ 250 Wh/kg. This is sufficient for small, general aviation electric airplanes, with a modest range no more than 200 km. This paper explores the possibility of a medium range (750 km) electric, four-seat, FAR-23 certifiable general aviation aircraft, assuming an energy density of 1500 Wh/kg, projected to be available in 2025. It presents the conceptual and preliminary design of such an aircraft, which includes weight and performance sizing, fuselage design, wing and high-lift system design, empennage design, landing gear design, weight and balance, stability and control analysis, drag polar estimation, environmental impact and final specifications. The results indicate that such an aircraft is indeed feasible, promising greener general aviation fleets around the world. Keywords: general aviation aircraft, electric aircraft, aircraft design

In this paper, an innovative methodology for the conceptual design of hybrid-powered airplanes is proposed. In particular, this work focuses on parallel hybrid architectures, in which the thermal engine is mechanically coupled to an electric motor, both supplying propulsive power during a limited number of flight phases, e.g. during takeoff and climb. This innovative solution is the subject of several studies being carried out since the current decade. In this paper, a brief overview of the works conducted by other researchers is provided. Then, an overall aircraft design methodology is proposed, which is derived from the most renewed design algorithms. The original contribution of this work is represented by the development of a methodology for the design of hybrid propulsion systems. Moreover, the proposed method is integrated within a global aircraft design methodology. In particular, several effects of the innovative system on the entire aircraft are considered, for instance the variation of the empty mass or the impacts on fuel consumption. The paper ends with some case studies of the proposed design methodology, and a discussion of the obtained results is provided.

Ensuring flight safety and aircraft structure lifetime is important today’s problem in development of up-to-date regional passenger aircraft. This paper deals with the aspects of providing static strength and lifetime of regional passenger aircraft. A series of factors and parameters were analyzed, which affect the aircraft static strength, lifetime, such as: fatigue, corrosion, wear, fretting-corrosion, human factor.n To ensure static strength, operational and design loads were determined for the entire range of design speeds and flight altitudes, overloads, aircraft weights and CG positions, fuel weight, cargo weight and various possible combinations of their distribution, taking into account the following: dynamic load and elastic characteristics of the aircraft’s design flying in disturbed air and while landing; dynamic load of the control system structure during maneuvering and under wind gusts; failures and malfunctions of systems that directly affect the strength characteristics. The results of flight tests showed that the An-148 100 / An-158 typical structure under the terms of static strength does not have features and parts that create emergency conditions or are unreliable, and confirmed the correctness of the choice of the established operational limitations presented for inclusion in the Flight Operation Manual. Conditions for operation of the An-148-100 / An-158 family during a design life of 30 years were determined on the basis of a comparative analysis of the corrosion resistance of the aircraft structures, whose service life exceeds 30 years. An-148-100 / An-158 airplanes are designed and manufactured in all-climate version in compliance with all the requirements for anti-corrosion protection. The aircraft used design and technological solutions to protect against loss of strength during operation from weathering, corrosion and abrasion, which allowed to state that the main power elements of the An-148-100 / An-158 aircraft typical structure are protected from reduction or loss of strength in operation for any reason, including weathering, corrosion and abrasion, as well as adequate ventilation and drainage. The provision of static strength and lifetime of regional passenger aircraft is confirmed by static, fatigue and flight tests of airplanes, reflected in technical reports with regard to strength, lifetime and service life of the An-148-100 / An-158 aircraft.

The basic results of calculation and research works carried out in the process of creation of power unit of regional passenger airplanes’ family are given. The design features of the propulsion engines and engine of the auxiliary power plant are described. The aforementioned propulsion system includes propulsion engines D-436-148 and engine AI-450-MS of auxiliary power plant. In order to comply with the requirements of Section 4 of the ICAO standard (noise reduction of the aircraft in site), in part of ensuring the noise reduction of engines, when creating the power plant of the An-148/An-158 aircraft family, a single- and double-layer acoustic filler was used in the structure of the engine nacelle and air intake. The use of electronic system for automatic control of propulsion engines such as FADEC and its integration into the digital airborne aircraft complex ensured the operation of engines, included in the power plant provided with high specific fuel consumption, as well as increased the level of automation of the power plant control and monitoring, and ensured aircraft automation landing in ICAO category 3A. In addition, the use of the aforementioned electronic system, allowed to operate the power plant of the aircraft in accordance with technical status. The use of the AI-450-MS auxiliary power plant with an electronic control system such as FADEC, and the drive of the service compressor from a free turbine, eliminated the effect of changes in power and air takeoff, on the deviation of the engine from optimal mode, which also minimized the fuel consumption. The use of fuel metering system TIS-158, allowed to ensure control of its condition and assemblies, without the use of auxiliary devices, built-in control means. In the fire protection system, the use of the electronic control and monitor unit, as well as the use of digital serial code for the exchange of information between the elements of the system and the aircraft systems, has reduced the number of connections, which increased the reliability of the system and reduced its weight characteristics.

In this paper, WC-12Co coating are prepared by two HVOF systems. The biggest difference between these two systems is the fuel gas use. Morphology and mechanical properties of the coatings are analyzed. The results show that the coating sprayed with Airplane Kerosene fuel gas is denser and the WC particles distribute more even than that sprayed with propane fuel gas. And the WC particles melt more fully. The hardness, Young’s Modules and fracture toughness of the coating sprayed with Airplane Kerosene fuel gas is higher than that sprayed with propane fuel gas.

The management of an urban context in a Smart City perspective requires the development of innovative projects, with new applications in multidisciplinary research areas. They can be related to many aspects of city life and urban management: fuel consumption monitoring, energy efficiency issues, environment, social organization, traffic, urban transformations, etc. Geomatics, the modern discipline of gathering, storing, processing, and delivering digital spatially referenced information, can play a fundamental role in many of these areas, providing new efficient and productive methods for a precise mapping of different phenomena by traditional cartographic representation or by new methods of data visualization and manipulation (e.g. three-dimensional modelling, data fusion, etc.). The technologies involved are based on airborne or satellite remote sensing (in visible, near infrared, thermal bands), laser scanning, digital photogrammetry, satellite positioning and, first of all, appropriate sensor integration (online or offline). The aim of this work is to present and analyse some new opportunities offered by Geomatics technologies for a Smart City management, with a specific interest towards the energy sector related to buildings. Reducing consumption and CO2 emissions is a primary objective to be pursued for a sustainable development and, in this direction, an accurate knowledge of energy consumptions and waste for heating of single houses, blocks or districts is needed. A synoptic information regarding a city or a portion of a city can be acquired through sensors on board of airplanes or satellite platforms, operating in the thermal band. A problem to be investigated at the scale A problem to be investigated at the scale of the whole urban context is the Urban Heat Island (UHI), a phenomenon known and studied in the last decades. UHI is related not only to sensible heat released by anthropic activities, but also to land use variations and evapotranspiration reduction. The availability of thermal satellite sensors is fundamental to carry out multi-temporal studies in order to evaluate the dynamic behaviour of the UHI for a city. Working with a greater detail, districts or single buildings can be analysed by specifically designed airborne surveys. The activity has been recently carried out in the EnergyCity project, developed in the framework of the Central Europe programme established by UE. As demonstrated by the project, such data can be successfully integrated in a GIS storing all relevant data about buildings and energy supply, in order to create a powerful geospatial database for a Decision Support System assisting to reduce energy losses and CO2 emissions. Today, aerial thermal mapping could be furthermore integrated by terrestrial 3D surveys realized with Mobile Mapping Systems through multisensor platforms comprising thermal camera/s, laser scanning, GPS, inertial systems, etc. In this way the product can be a true 3D thermal model with good geometric properties, enlarging the possibilities in respect to conventional qualitative 2D images with simple colour palettes. Finally, some applications in the energy sector could benefit from the availability of a true 3D City Model, where the buildings are carefully described through three-dimensional elements. The processing of airborne LiDAR datasets for automated and semi-automated extraction of 3D buildings can provide such new generation of 3D city models.

Evolving aircraft and engine technologies, as well as advancements in avionics, have resulted in a new generation of fighter aircraft. In order for an air force to remain survivable in such an environment it must face the necessity of either acquiring new aircraft or upgrading its fleet. Today, acquisition of new aircraft may not be an economically or politically viable solution. The newest aircraft, those with a thrust-to-weight ratio exceeding 1 to 1, generally exceed $20 million, exclusive of support costs. Politically, sale of such state-of-the-art aircraft to friendly countries may not be possible given the current FX aircraft export policy, and the fiscal posture of the country. However, there is an alternative to new aircraft acquisition, and that is functional modernization: the modernization of potentially viable systems through the implementation of new and available technologies. The Boeing Military Airplane Company and Pratt & Whitney have teamed in the newest aircraft functional modernization proposal, the F-4 Super Phantom. The full modernization package includes a new centerline conformal fuel tank, new digital avionics, and re-engining with new PW1120 engines. This paper examines the initial feasibility study conducted by Pratt & Whitney and Boeing to determine the feasibility of a functionally modernized F-4.

The precision of the altitude measurement system installed in some type airplane does not fulfill the need of the airborne equipment, this paper propose a method based on the federated filter which utilizes the data of the air data computer system (ADS), inertial navigation system (INS) and the GPS to improve the precision and stability of the altitude output. The results of simulation show that the algorithm takes full advantage of all of the sub-system, which reduces the error of the ADS and improves the altitude output precision. Meanwhile the method may separate some faulted sub-system (e.g. GPS) and reform the system, which renders the system better fault tolerant and real-time performance.

Principal results of the computational and research work performed during development of a regional passenger aircraft to ensure its aerodynamic characteristics are given. When creating the An-148-100/An-158 family of aircraft, such level of the aircraft aerodynamic perfection was achieved, which ensured fulfillment of the specified requirements for their flight performance – maximum speed, cruising flight altitude and flight range with different payloads. The developed aerodynamic configuration made it possible to create a family of regional passenger high-wing planes with a flight speed of up to 870 km/h (true speed) (M = 0.8), which have no analogues in the world aviation industry. Developed for the An-148-100 / An- 158 aircraft, supercritical profiles of the new generation with a large maximum relative thickness formed the basis of the aerodynamic configuration of a high-speed wing with moderate sweep. The aircraft lift-to-drag ratio in cruise flight is Kcruise = 15.8, which corresponds to the worldwide values. Developed aerodynamic configuration of the wing high-lift devices provides high bearing properties of the wing during take-off and landing stages, which allows to fully meet the requirements for the runway required length of the base airfields Lrun = 1485...1950 m. Developed algorithms are implemented in the electric remote control system and provide necessary standard characteristics of stability, controllability and flight dynamics in the main control mode. Selected margins of the aircraft’s own static stability and effectiveness of its controls ensure safe completion of the flight in standby control mode. The certification flight tests of the An-148-100/An-158 airplanes confirmed full compliance of their take-off and landing performance, as well as the stability, controllability and flight dynamics characteristics with the requirements of the Certification basis in both standard and in failure situations tested in flight tests. Necessary and sufficient amount of experimental work was conducted in the lowspeed and high-speed wind tunnels of the ANTONOV SC and TsAGI to verify the aerodynamic and spin characteristics of the An-148-100/An-158 airplane models, which improved the aerodynamic configuration of the aircraft and its individual units and allowed to apply the work results in calculation of aircraft strength, as well as for development of their systems.

Purpose This paper deals with the estimation of the necessary masses of propulsion components for multirotor UAS. Originally, within the design process of multirotors, this is an iterative problem, as the propulsion masses contribute to the total takeoff mass. Hence, they influence themselves and cannot be directly calculated. The paper aims to estimate the needed propulsion masses with respect to the requested thrust because of payload, airframe weight and drag forces and with respect to the requested flight time. Design/methodology/approach Analogue to the well-established design synthesis of airplanes, statistical data of existing electrical motors, propellers and rechargeable batteries are evaluated and analyzed. Applying Rankine and Froude’s momentum theory and a generic model for electro motor efficiency factors on the statistical performance data provides correlations between requested performance and, therefore, needed propulsion masses. These correlations are evaluated and analyzed in the scope of buoyant-vertical-thrusted hybrid UAS. Findings This paper provides a generic mathematical propulsion model. For given payloads, airframe structure weights and a requested flight time, appropriate motor, propeller and battery masses can be modelled that will provide appropriate thrust to lift payload, airframe and the propulsion unit itself over a requested flight time. Research limitations/implications The model takes into account a number of motors of four and is valid for the category of nano and small UAS. Practical implications The presented propulsion model enables a full numerical design process for vertical thrusted UAS. Hence, it is the precondition for design optimization and more efficient UAS. Originality/value The propulsion model is unique and it is valid for pure multirotor as well as for hybrid UAS too.

Microwave radar imaging plays a key role in several civilian and defense applications, such as security, surveillance, diagnostics and monitoring in civil engineering and cultural heritage, environment observation, with particular emphasis on disasters and crisis management, where it is required to remotely sense the area of interest in a timely, safe and effective way. To address these constraints, a technological opportunity is offered by radar systems mounted onboard smart and flexible platforms, such as ground-based ones, airplanes, helicopters, drones, unmanned aerial and ground vehicles (UAV and UGV). For this reason, radar imaging based on data collected by such platforms is gaining interest in the remote sensing community. However, a full exploitation of smart and flexible radar systems requires the development and use of image formation techniques and reconstruction approaches able to exploit and properly deal with non-conventional data acquisition configurations. The other main issue is related to the need to operate in challenging environments, and still deliver high target detection, localization and tracking. These environments include through the wall imaging, rugged terrain and rough surface/subsurface. In these cases, one seeks mitigation of the adverse effects of clutter and multipath via the implementation of effective signal processing strategies and electromagnetic modeling.

Airplane has been widely used as transportation compared to ship or car due to the short time journey. This phenomenon contributes to high demand or airline network for many places around the world and resulted in more competition for the airline industry due to changes in economy and increase in number of airlines. Besides, the increase in price of fuel can also be a major burden to the airline to maintain or gain profit. In order to overcome the fuel and cost problem, few measures can be taken including implementing effective aircraft loading system to optimize fuel weight and manage centre of gravity (CG), an aerodynamically clean aircraft, flight planning based on good data and optimal use of systems for example bleed, flaps and gear. For this study, load planning system for a Boeing 737-800 aircraft is considered to obtain a good position of CG for better fuel consumption. A load planning system was designed and developed using LabVIEW 2016 which can easily be integrated with sensors to produce a complete system. This system capable of receiving baggage weight as input and arranging the baggage to ensure the CG location is within the stipulated range. The efficiency of this system was validated by testing an aircraft model inside a wind tunnel and observing the performance of the aircraft when loads were arrange randomly and also based on the proposed arrangement by the system. As a result from the testing, by arranging the loads using the system that has been developed, a better flight performance in term of lift to drag ratio can be obtained which was 10.2 compared to randomly arranging the loads which was 7.9. Thus, by having a good load planning can reduce the fuel consumption and also improve the flight performance.

HAPS (high-altitude pseudosatellites) are flight machines, airplane type, generally without pilot which fly in a definite zone at 18-22 km altitude, providing communication and surveillance services. These flight machines do not leave the atmosphere, and their purpose is to maintain a constant flight level for as long time as possible in the interest zone (e.g., five years) to fulfill their mission. HAPS energetic system proposed in this paper has to feed the electric propulsion system of HAPS (12.5 kW) and also to feed on-board equipment (navigation, data links, scientific equipment, etc.). On-board energy sources have to maintain HAPS in the interest zone for long periods. For this reason, it is used in the present solar power sources. A part of the generated energy is consumed on board; the rest is stored daytime and consumed nighttime. So, the system is provided with energy generation systems and also with storage and management systems. HAPS energetic system is a hybrid type, with two or more power sources. In this case, power sources are photovoltaic panels are used daytime and fuel cell are used nighttime, and also, a battery and/or a supercapacitor is used in transition periods from day to night and in peak load periods. In this paper, an electric power system used nighttime is designed and analysed. In this situation, the primary power source is the fuel cell and the secondary power sources are battery and/or supercapacitor. There are used numerical simulations models, developed in Matlab/Simulink, for all hybrid power source components: fuel cell stack, battery system, supercapacitors, conversion system, and fuzzy logic power management system. For a part of these components, there are used existing simulation models in Matlab/Simulink, adapted to these simulation requirements, and for others, there are designed and implemented simulation schemes according to these simulation requirements. An important component of the hybrid power source is the power conversion system which adapts the power sources parameters to consumer input requirements. A fuzzy logic power management system is designed.

Recently, a great interest in search of alternate means of power for the traditional fuel for aircraft propulsion is raised so as to decrease gas emissions and reduce operating costs. For the small and micro unmanned aerial vehicles or small transportation aircraft, there are many challenges in the direction of constructing an electric or solar powered airplane whose wings may possibly be sheltered with photo voltaic PV solar panels to harvest sun’s energy for propulsion. Greatest remarkably success solar powered aircraft has attracted the attention of researchers other than UAV and small aircraft supporters. Although the solar panel is thin, its thickness is considerable compared to the airfoil thickness. This paper aims to evaluate the impact of adding the solar panel over a low camber airfoil suitable for low-Reynolds number flights, as mini UAVs. Three panel installation configurations are examined to stand on the most suitable configuration, in terms of aerodynamic efficiency. The analysis is based on the airfoil characteristics (lift, drag, and moment) and the pressure distribution over the airfoil surface. A parametric study is conducted to study the effect of the solar panel size, thickness, and position on the aerodynamic performance.

Augmentation of the flight range, speed and altitude along with the extension of the number of missions accomplished by aircraft has resulted in the expansion and complication of the functions performed by the aircraft air distribution systems. Thus, for instance, the air distribution system of a modern transport airplane includes:- cabin air conditioning system;- underfloor area heating system;- wing ice protection and fuel tank venting system; - engine air intake ice protection system;- engine pneumatic starting system;- the system of controlled air extraction from the equipment/avionics compartment;- hydraulic tank pressurization system;- turbine-driven hydraulic pump drive;- radio equipment and radar pressurization system; - auxiliary power unit compartment heating system;- cabins air conditioning using ground sources;- cabins ventilation using atmospheric air;- air supply for inert gas generation In terms of structure design the aircraft air systems are a complex of heat exchange mechanisms, cooling turbines, compressors, filters, limiters and regulators, mixers, pipelines and other components interacting with each other and with the environment through the exchange of the flows of working media, heat and mechanical energy. The system purpose is implemented in the process of its functioning which implies on-board generation of working medium and its supply to consumers with the quantity and quality of the medium conditioned by external characteristics. External characteristic is a quantification of the purpose of system functioning. As an engineering entity the air distribution systems are characterized by a number of functional indicators. These include the system reliability and weight, expenditure of energy and working medium, overall dimensions, external energy release, factor of safety, cost, etc. In the practical development of air distribution systems, when meeting the cooling performance requirements use is later made, as a general rule, of such indicator as "installation weight", less frequently – of the integrated "reduced" weight indicator with introduction of limitations on other indicators. Designing the air distribution systems involves lookup for a compromise between a number of conflicting requirements: minimization of the installation weight and energy losses, high system reliability, fail safety, rigorous geometric constraints, high manufacturability and comparatively low cost of production. Application of the mathematical statics techniques makes it possible to optimize parameters of the air system.

Sightings of marine mammals made by protected species observers (PSOs) on manned aircraft were compared to sightings obtained from later review of high-definition (HD) video and digital single lens reflex (DSLR) camera imagery covering the same swaths and collected concurrent with the PSO observations. If the data were comparable, future similar surveys could be conducted with unmanned aerial systems or manned aircraft without PSOs. Two reviews were conducted on the DSLR images: one used image enhancement and scanned the images at full resolution of the cameras (detailed review) and the other flashed images at one ninth resolution on monitors for three to four seconds using a slide show format to simulate the view a PSO would have out an airplane window. Image reviewers saw fewer animals in HD video than did PSOs but sample sizes were small. During detailed review of DSLR imagery, reviewers saw similar numbers of cetaceans and polar bears and slightly more pinnipeds as compared to PSOs. PSOs saw more animals than the quick review found, but changes to the quick review process are suggested that will increase detection rates. Additional data are required to confirm the results presented here and to determine whether photographic versus PSO detections are similar across varying survey conditions.

Although it accounts for only 4.2% of the total global warming potential, the concern today is that aviation generated CO2 is projected to grow to approximately 5.7% by 2050. Aviation emissions are growing faster than any other sector and they risk undermining the progress achieved through emission cuts in other areas of the economy. Rapidly emerging hydrogen and fuel-cell-based technologies could be developed for future replacement of on-board electrical systems in “more-electric” or “all-electric” aircrafts. Primary advantages of deploying these technologies are low emissions and low noise (important features for commuter airplanes, which takeoff and land in urban areas). Solid oxide fuel-cell (SOFC) systems could result advantageous for some aeronautical applications due to their capability of accepting hydrocarbons and high energy-density fuels. Moreover they are suitable for operating in combined-heat-and-power configurations, recovering heat from the high-temperature exhaust gases, which could be used to supply thermal loads therefore reducing the electric power requested by the aircraft. ENFICA-FC is a project selected by the European Commission in the Aeronautics and Space priority of the Sixth Framework Programme (FP6) and led by Politecnico di Torino, in Turin, Italy. One of the objectives of the project is to carry out a feasibility study on a more-electric intercity aircraft (regional jet: 32 seats). After the characterization of the power consumption of electrical and nonelectrical loads, and the definition of a mission profile, the design of the SOFC-based energy system as well as the simulation of a complete mission is performed hypothesizing different system configurations. The simulation concerns both the stack (current and current density, cell and stack voltage, etc.) and the balance-of-plant (air compressor power, gross stack power, system efficiency, etc.). The obtained results are analyzed and discussed.

AbstractThe advanced space missions need for more power opened the way for advanced nuclear reactors and for alternative power conversion procedures. The most advanced power systems available in space are the fuel cells and nuclear reactors. Both systems manifest low efficiencies for converting the primary energy into electricity and as consequence are requiring high heat dump into space mainly by infrared radiation. The thermo-nuclear power generator also requires a high temperature gas turbine and a mechano-electric generator, finally driving to low conversion efficiencies. The new nano-materials offer the possibility of creating direct energy conversion devices able of achieving high conversion efficiencies up to 99% in the cryogenic versions. The interest for direct conversion of the nuclear energy into electricity appeared in early 1940th, by the invention of the thermo-ionic fission device by Linder. Then a series of patents and scientific papers improved gradually the designs and performances of the devices, up to the actual concepts of beta-voltaic and liquid-electronics. The most intuitive direct conversion device looks mainly like a super mirror- or a heterogeneous super-capacitor. The issues on its operation are related to global conversion efficiencies and the stable operation life-time in high radiation field. There are combinations of nano-structures and actinides assuring both the neutron flux stability, by meeting criticality conditions and the direct conversion or the nuclear energy into electricity. Achieving a high efficiency internal conversion of the nuclear energy into electricity is not enough if it is not completed by a high efficiency power extraction system from the nuclear reactor core into the outside load. The development of the new MEMS devices and micro electronics in the 40 nm technologies provides an excellent background for the production of the electric power harvesting and conversion devices embedded in the fuel. The new nano-structured materials may be produced as radiation energy harvesting tiles that are free of actinides, using them for harvesting the energy of radioactive sources and controlled fusion devices, or may include actinides in their structure achieving critical or sub-critical accelerator driven nuclear reactor assemblies. Another predictable advantage of the nano-structure is the property of self-repairing and self-organizing to compensate the radiation damage and improve the lifetime. Due to direct conversion the power density of the new materials may increase from the actual average of 0.2 kw/cm3 to about 1 kw/mm3 driving to miniaturization of nuclear power sources and reductions of the shield weight. At these dimensions and power densities of few thousands horse power per liter the nuclear power source becomes suitable for mobile applications as powering trains, strategic airplanes, etc. These new developments may drive to the production of high power solid-state compact nuclear battery for space applications, leading to a new development stage.

Nanotechnology is new frontiers of this century. The world is facing great challenges in meeting rising demands for basic commodities(e.g., food, water and energy), finished goods (e.g., cellphones, cars and airplanes) and services (e.g., shelter, healthcare and employment) while reducing and minimizing the impact of human activities on Earth’s global environment and climate. Nanotechnology has emerged as a versatile platform that could provide efficient, cost-effective and environmentally acceptable solutions to the global sustainability challenges facing society. In recent years there has been a rapid increase in nanotechnology in the fields of medicine and more specifically in targeted drug delivery. Opportunities of utilizing nanotechnology to address global challenges in (1) water purification, (2) clean energy technologies, (3) greenhouse gases management, (4) materials supply and utilization, and (5) green manufacturing and hemistry. Smart delivery of nutrients, bio-separation of proteins, rapid sampling of biological and chemical contaminants, and nano encapsulation of nutraceuticals are some of the emerging topics of nanotechnology for food and agriculture. Nanotechnology is helping to considerably improve, even revolutionize, many technology and Industry sectors: information technology, energy, environmental science, medicine, homeland security, food safety, and transportation, among many others. Today’s nanotechnology harnesses current progress in chemistry, physics, materials science, and biotechnology to create novel materials that have unique properties because their structures are determined on the nanometer scale. This paper summarizes the various applications of nanotechnology in recent decades Nanotechnology is one of the leading scientific fields today since it combines knowledge from the fields of Physics, Chemistry, Biology, Medicine, Informatics, and Engineering. It is an emerging technological field with great potential to lead in great breakthroughs that can be applied in real life. Novel Nano and biomaterials, and Nano devices are fabricated and controlled by nanotechnology tools and techniques, which investigate and tune the properties, responses, and functions of living and non-living matter, at sizes below100 nm. The application and use of Nano materials in electronic and mechanical devices, in optical and magnetic components, quantum computing, tissue engineering, and other biotechnologies, with smallest features, widths well below 100 nm, are the economically most important parts of the nanotechnology nowadays and presumably in the near future. The number of Nano products is rapidly growing since more and more Nano engineered materials are reaching the global market the continuous revolution in nanotechnology will result in the fabrication of nanomaterial with properties and functionalities which are going to have positive changes in the lives of our citizens, be it in health, environment, electronics or any other field. In the energy generation challenge where the conventional fuel resources cannot remain the dominant energy source, taking into account the increasing consumption demand and the CO2 .Emissions alternative renewable energy sources based on new technologies have to be promoted. Innovative solar cell technologies that utilize nanostructured materials and composite systems such as organic photovoltaic offer great technological potential due to their attractive properties such as the potential of large-scale and low-cost roll-to-roll manufacturing processes

Reduced greenhouse gas emissions via improved energy efficiency represent the ultimate challenge for the energy economy of the future. In this context, fuel cells for power generation aboard aircrafts have a promising potential to effectively contribute to the greening of air transportation. They can simplify today’s aircraft comprising electric, pneumatic, and hydraulic systems toward a more electric airplane. Although they are not considered in the short term as an alternative propulsion system for commercial aviation, many efforts are being devoted to their use as auxiliary power units and even aiming to build a distributed power network that might alleviate duties of the engine driven generators. In addition they allow new functions such as zero emission during taxiing on ground and/or increase safety by replacing the emergency ram-air turbine (RAT) by a fuel cell based emergency power generator. The present paper focuses on the effort that Compañía Española de Sistemas Aeronáuticos (CESA) is putting into the development of an aeronautical fuel cell system based on a high-temperature PEMFC covering all aspects from fundamental research in materials and processes to final integration concepts as a function of different architectures. A great deal of time and effort has been invested to overcome the challenges of PEM fuel cell operation at high temperatures. Among the advantages of these systems are the enhancement of electrochemical kinetics, the simplification of water management and cooling, the recovery of wasted heat, and the possibility of utilizing reformed hydrogen thanks to higher tolerance to impurities. However, new problems arise with the high-temperature concept that must be addressed such as structural and chemical degradation of materials at elevated temperatures. One of the aeronautical applications, where a fuel cell has an important role to play in the short term is the emergency power unit. Weight and mechanical complexity of traditional ram-air turbines could be drastically reduced by the introduction of a hydrogen fueled system. In addition, the output of the fuel cell is aircraft’s speed independent. This means additional power supply in case of emergency allowing a safer landing of the aircraft. However, a RAT replacement must overcome the specific difficulties concerning the very short start-up times allowed and the heating/cooling strategies to quickly raise the temperature to elevated levels and accurately maintaining the optimum operating range once in service.

Gas turbine engines (GTEs) are widely used for power generation, ranging from stationary power plants to airplane propulsion systems. Compressor fouling is the dominant degradation mode in gas turbines that leads to economic losses due to power deficit and extra fuel consumption. Washing of the compressor removes the fouling matter and retrieves the performance, while causing a variety of costs including loss of production during service time. In this paper, the effect of fouling and washing on the revenue of the power plant is studied, and a general solution for the optimum time between washes of the compressor under variable fouling rates and demand power is presented and analyzed. The framework calculates the savings achievable with optimization of time between washes during a service period. The methodology is utilized to optimize total costs of fouling and washing and analyze the effects and sensitivities to different technical and economic factors. As a case study, it is applied to a sample set of cumulative gas turbine operating data for a time-between-overhauls and the potential saving has been estimated. The results show considerable saving potential through optimization of time between washes.

AbstractThe uses of nanofluid in cooling technology is growing. The nanofluid is made up of metallic and nonmetallic particles that are distributed in a base fluid. This research provides a summary of fuel cell models, uses, and how they function. Researchers have made significant contributions in the following era due to the importance of bioconvection in nanotechnology and a variety of biological systems. The idea of the recent work is to evaluate the aspects of the Cattaneo–Christov (C–C) heat and mass flux model, the second-order boundary with melting phenomenon on the bioconvective flow of viscoelastic nanofluid across a cylinder. The nature of the activation energy, thermal conductivity is also taken into account. Appropriate similarity transformations are utilized to reframe the PDEs of the modeled system into a system of ODEs. The governing equations for the renovated system of ODEs are treated by a shooting function. Here bvp4c built-in function computational tool MATLAB is used. The two-dimensional flow has ceased application in several areas, such as polymer industry, material synthesis technology, nano-biopolymer computer graphics processing, industry, mechanical engineering, airplane structures, and scientific research, which is much more useful in nanotechnology. The results of emerging important flow-field parameters are investigated with the aid of graphs and numerical results.

Perhaps the supreme quality of print is one that is lost on us, since it has so casual and obvious an existence (McLuhan 160). Print Machine (Thad Donovan, 1995) In the introduction to his book on 9/11, Welcome to the Desert of the Real, Slavoj Zizek uses an analogy of letter writing to emphasize the contingency of post-9/11 reality. In the example, Zizek discusses the efforts of writers to escape the eyes of governmental censors and a system that used blue ink to indicate a message was true, red ink to indicate it was false. The story ends with an individual receiving a letter from the censored country stating that the writer could not find any red ink. The ambiguity and the duplicity of writing, suggested in Zizek’s tale of colored inks, is a condition of the contemporary world, even if we are unaware of it. We exist in an age in which print—the economization of writing—has an increasingly significant and precarious role in our lives. We turn to the Internet chat room for textual interventions in our sexual, political and aesthetic lives. We burn satanic Harry Potter books and issue fatwas against writers like Salman Rushdie. We narrate our lives using pictures, fonts of varying typeface and color, and sound on our personalized homepages. We throw out our printed books and buy audio ones so we can listen to our favorite authors in the car. We place trust of our life savings, personal numbers, and digital identity in the hands of unseen individuals behind computer screens. Decisively, we are a print people, but our very nature of being dependent on the technologies of print in our public and private lives leads to our inability to consider the epistemological, social and existential effects of print on us. In this article, I focus on the current manifestations of print—what I call “newprint”—including their relationships to consumerism, identity formation and the politics of the state. I will then consider the democratic possibilities of print, suggested by the personalization of print through the Internet and home publishing, and conclude with the implications of the end of print that include the possibility of a post-print language and the middle voice. In order to understand the significance of our current print culture, it is important to situate print in the context of the history of communication. In earlier times, writing had magical associations (Harris 10), and commonly these underpinnings led to the stratification of communities. Writing functioned as a type of black box, “the mysterious technology by which any message [could] be concealed from its illiterate bearer” (Harris 16). Plato and Socrates warned against the negative effects of writing on the mind, including the erosion of memory (Ong 81). Though it once supplemented the communicational bases of orality, the written word soon supplanted it and created a dramatic existential shift in people—a separation of “the knower from the known” (Ong 43-44). As writing moved from the inconvenience of illuminated manuscripts and hand-copied texts, it became systemized in Gutenberg print, and writing then took on the signature of the state—messages between people were codified in the technology of print. With the advent of computer technologies in the 1990s, including personal computers, word processing programs, printers, and the Internet, the age of newprint begins. Newprint includes the electronic language of the Internet and other examples of the public alphabet, including billboards, signage and the language of advertising. As much as members of consumer society are led to believe that newprint is the harbinger of positive identity construction and individualism, closer analysis of the mechanisms of newprint leads to a different conclusion. An important context of new print is found in the space of the home computer. The home computer is the workstation of the contemporary discursive culture—people send and receive emails, do their shopping on the Internet, meet friends and even spouses through dating services, conceal their identity on MUDs and MOOs, and produce state-of-the-art publishing projects, even books. The ubiquity of print in the space of the personal computer leads to the vital illusion that this newprint is emancipatory. Some theorists have argued that the Internet exhibits the spirit of communicative action addressed by Juergen Habermas, but such thinkers have neglected the fact that the foundations of newprint, just like those of Gutenberg print, are the state and the corporation. Recent advertising of Hewlett-Packard and other computer companies illustrates this point. One advertisement suggested that consumers could “invent themselves” through HP computer and printer technology: by using the varied media available to them, consumers can make everything from personalized greeting cards to full-fledged books. As Friedrich Kittler illustrates, we should resist the urge to separate the practices of writing from the technologies of their production, what Jay David Bolter (41) denotes as the “writing space”. For as much as we long for new means of democratic and individualistic expression, we should not succumb to the urge to accept newprint because of its immediacy, novelty or efficiency. Doing so will relegate us to a mechanistic existence, what is referenced metaphorically in Thad Donovan’s “print machine.” In multiple contexts, newprint extends the corporate state’s propaganda industry by turning the written word into artifice. Even before newprint, the individual was confronted with the hegemony of writing. Writing creates “context-free language” or “autonomous discourse,” which means an individual cannot directly confront the language or speaker as one could in oral cultures (Ong 78). This further division of the individual from the communicational world is emphasized in newprint’s focus on the aesthetics of the typeface. In word processing programs like Microsoft Word, and specialized ones like TwistType, the consumer can take a word or a sentence and transform it into an aesthetic formation. On the word processing program that is producing this text, I can choose from Blinking Background, Las Vegas Lights, Marching Red or Black Ants, Shimmer, and Sparkle Text. On my campus email system I am confronted with pictorial backgrounds, font selection and animation as an intimate aspect of the communicational system of my college. On my cell phone I can receive text messages, and I can choose to use emoticons (iconic characters and messages) on the Internet. As Walter Ong wrote, “print situates words in space more relentlessly than writing ever did … control of position is everything in print” (Ong 121). In the case of the new culture of print, the control over more functions of the printed page, specifically its presentation, leads some consumers to believe that choice and individuality are the outcomes. Newprint does not free the writer from the constraints imposed by the means of traditional print—the printing press—rather, it furthers them as the individual operates by the logos of a predetermined and programmed electronic print. The capacity to spell and write grammatically correct sentences is abated by the availability of spell- and grammar-checking functions in word processing software. In many ways, the aura of writing is lost in newprint in the same way in which art lost its organic nature as it moved into the age of reproducibility (Benjamin). Just as filters in imaging programs like Photoshop reduce the aesthetic functions of the user to the determinations of the software programmer, the use of automated print technologies—whether spell-checking or fanciful page layout software like QuarkXpress or Page Maker—will further dilute the voice of the writer. Additionally, the new forms of print can lead to a fracturing of community, the opposite intent of Habermas’ communicative action. An example is the recent growth of specialized languages on the Internet. Some of the newer forms of such languages use combinations of alphanumeric characters to create a language that can only be read by those with the code. As Internet print becomes more specialized, a tribal effect may be felt within our communities. Since email began a few years ago, I have noticed that the nature of the emails I receive has been dramatically altered. Today’s emails tend to be short and commonly include short hands (“LOL” = “laugh out loud”), including the elimination of capitalization and punctuation. In surveying students on the reasons behind such alterations of language in email, I am told that these short hands allow for more efficient forms of communication. In my mind, this is the key issue that is at stake in both print and newprint culture—for as long as we rely on print and other communicational systems as a form of efficiency, we are doomed to send and receive inaccurate and potentially dangerous messages. Benedict Anderson and Hannah Arendt addressed the connections of print to nationalistic and fascist urges (Anderson; Arendt), and such tendencies are seen in the post-9/11 discursive formations within the United States. Bumper stickers and Presidential addresses conveyed the same simplistic printed messages: “Either You are with Us or You are with the Terrorists.” Whether dropping leaflets from airplanes or in scrolling text messages on the bottom of the television news screen, the state is dependent on the efficiency of print to maintain control of the citizen. A feature of this efficiency is that newprint be rhetorically immediate in its results, widely available in different forms of technology, and dominated by the notion of individuality and democracy that is envisioned in HP’s “invent yourself” advertsiements. As Marshall McLuhan’s epigram suggests, we have an ambiguous relationship to print. We depend on printed language in our daily lives, for education and for the economic transactions that underpin our consumer world, yet we are unable to confront the rhetoric of the state and mass media that are consequences of the immediacy and magic of both print and new print. Print extends the domination of our consciousness by forms of discourse that privilege representation over experience and the subject over the object. As we look to new means of communicating with one another and of expressing our intimate lives, we must consider altering the discursive foundations of our communication, such as looking to the middle voice. The middle voice erases the distinctions between subjects and objects and instead emphasizes the writer being in the midst of things, as a part of the world as opposed to dominating it (Barthes; Tyler). A few months prior to writing this article, I spent the fall quarter teaching in London. One day I received an email that changed my life. My partner of nearly six years announced that she was leaving me. I was gripped with the fact of my being unable to discuss the situation with her as we were thousands of miles apart and I struggled to understand how such a significant and personal circumstance could be communicated with the printed word of email. Welcome to new print! References Anderson, Benedict. Imagined Communities: Reflections on the Origin and Spread of Nationalism. London: Verso, 1991. Arendt, Hannah. The Origins of Totalitarianism. San Diego: Harcourt Brace, 1976. Barthes, Roland. “To Write: An Intransitive Verb?” The Languages of Criticism and the Sciences of Man: The Structuralist Controversy. Ed. Richard Macksey and Eugenio Donato. Baltimore: Johns Hopkins UP, 1970. 134-56. Benjamin, Walter. “The Work of Art in the Age of Its Technological Reproducibility: Second Version.” Walter Benjamin: Selected Writings, Volume 3: 1935-1938. Cambridge: Belknap/Harvard, 2002. Bolter, Jay David. Writing Space: The Computer, Hypertext, and the History of Writing. Hillsdale, NJ: Lawrence Erlbaum, 1991. Habermas, Jürgen. The Theory of Communicative Action. Vol. I. Boston: Beacon Press, 1985. Harris, Roy. The Origin of Writing. La Salle, IL: Open Court, 1986. Kittler, Friedrich A. Discourse Networks 1800/1900. Stanford: Stanford UP, 1990. McLuhan, Marshall. Understanding Media: The Extensions of Man. Cambridge: MIT P, 1994. Ong, Walter J. Orality and Literacy: The Technologizing of the Word. London: Routledge, 1991. Tyler, Stephen A. “The Middle Voice: The Influence of Post-Modernism on Empirical Research in Anthropology.” Post-modernism and Anthropology. Eds. K. Geuijen, D. Raven, and J. de Wolf. Assen, The Neatherlands: Van Gorcum, 1995. Zizek, Slavoj. Welcome to the Desert of the Real. London: Verso, 2002. Citation reference for this article MLA Style Lukas, Scott A. "Nevermoreprint." M/C Journal 8.2 (2005). echo date('d M. Y'); ?> <http://journal.media-culture.org.au/0506/04-lukas.php>. APA Style Lukas, S. (Jun. 2005) "Nevermoreprint," M/C Journal, 8(2). Retrieved echo date('d M. Y'); ?> from <http://journal.media-culture.org.au/0506/04-lukas.php>.