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Rotorcraft in the Performance Based Navigation International Civil Aviation Organization Implementation

Abstract

European Commision adopted in July new regulations about laying down airspace usage requirements and operating procedures concerning performance based navigation. It is next step in realization of the the global program PBN ICAO. At the 36th General Assembly of ICAO held in 2007, the Republic of Poland agreed to ICAO resolution A36-23 which urges all States to implement PBN. In future aviation concepts the use of Performance Based Navigation (PBN) is considered to be a major Air Traffic Management (ATM) concept element. ICAO has drafted standards and implementation guidance for PBN in the ICAO Doc 9613 “PBN Manual”. The Based Performance Navigation Concept represents and shift from sensor-based to performance based navigation connected with criteria for navigation: accuracy, integrity, availability, continuity and functionality depending on the phase of the flight. Through PBN and changes in the communication, surveillance and ATM domain, many advanced navigation applications are possible to improve airspace efficiency, improve airport sustainability, reduce the environmental impact of air transport in terms of noise and emission, increase safety and improve flight efficiency.

Open access
Structural and magnetic studies on Co-Zn nanoferrite synthesized via sol-gel and combustion methods

Abstract

Co–Zn nanocrystalline ferrites with chemical composition Co0:5Zn0:5Fe2O4 were synthesized by sol-gel and combustion methods. The sol-gel method was carried out in two ways, i.e. based on chelating agents PVA and PEG of high and low molecular weights. In auto-combustion method, the ratio of citric acid to metal nitrate was taken as 1:1, while in sol-gel method the chelating agents were taken based on oxygen balance. All the three samples were studied by thermogravimetric and differential thermal analysis for the identification of phase formation and ferritization temperature. The synthesized samples were characterized by powder X-ray diffraction and FT-IR spectroscopy without any thermal treatment. The measured lattice constants and observed characteristic IR absorption bands of the three samples are in good agreement with the reported values showing the formation of a cubic spinel structure. The crystallite sizes of all samples were determined using high intensity peaks and W-H plot. Size-Strain Plot method was also implemented since two of the samples showed low crystallite sizes. The least crystallite size (5.5 nm) was observed for the sample CZVP while the highest (23.8 nm) was observed for the sample CZCA. Cation distribution was proposed based on calculated and observed intensity ratios of selected planes from X ray diffraction data. All structural parameters were presented using experimental lattice constant and oxygen positional parameter, and they correlated with FT-IR results. Magnetic measurements were carried out using vibrating sample magnetometer at room temperature to obtain the characteristic parameters such as saturation magnetization, coercivity, remanence, squareness ratio and Bohr magnetons. Among all, the sample synthesized via citric acid autocombustion method displayed a remarkably higher magnetization of 53 emu/g and the remaining two samples displayed low magnetization values owing to their smaller crystallite sizes.

Open access
Structural and optical properties of Dy3+ doped Sr2SiO4 phosphors

Abstract

Dysprosium doped strontium silicate phosphor namely (Sr2SiO4:Dy3+) was prepared by low-temperature solution combustion method using urea (CO(NH2)2) as a fuel. The material was characterized by powder X-ray diffraction (XRD), FT-IR, SEM and EDX. The average crystallite sizes was calculated by Scherer formula. Thermoluminescence study was carried out for the phosphor which showed single glow curve. The kinetic parameter were calculated by using Chen’s glow curve method. Photoluminescence spectra revealed strong transition at 473 nm (blue), 571 nm (yellow) and weak transition at 645 nm (red). These peaks were assigned to transition 4F9/26H15/2, 13/2, 11/2. CIE graph of Sr2SiO4:Dy3+ phosphor is suitable for the generation of white light emission.

Open access
Synthesis and characterization of high-efficiency low-cost solar cell thin film

Abstract

Polycrystalline chalcogenide semiconductors play a vital role in solar cell applications due to their outstanding electrical and optical properties. Among the chalcogenide semi-conductors, CdZnS is one kind of such important material for applications in various modern solid state devices such as solar cells, light emitting diode, detector etc. Due to their applications in numerous electro-optic devices, group II-VI semiconductors have been studied extensively. In recent years, major attention has been given to the study of electrical and optical properties of CdZnS thin films. In this work, Cd1−xZnxS thin films were prepared by chemical bath deposition technique. Phase purity and surface morphology properties were analyzed using field emission scanning electron microscope (FE-SEM) and X-ray diffraction (XRD) studies. Chemical composition was studied using energy dispersive spectrophotometry (EDS). Optical band gap property was investigated using UV-Spectroscopy. Electrical conductivity studies were performed by two probe method and thermoelectric power setup (TEP) to determine the type of the material. This work reports the effect of Zn on structural, electrical, microstructural and optical properties of these films.

Open access
Waste Management Integration with Green Quality Function Deployment (G-QFD) for Healthcare Centre

Abstract

High doses of medical waste evidence that health waste management is problematic. A case study was conducted at various health institutions. This research analyzes various issues in the area of medical waste management. The research examines the perception of staff regarding medical waste management. The purpose of the study is to investigate the level of knowledge, attitudes and role of health practitioners in the management of medical waste.

Here the quality index and the environmental index of two health centers are studied; one is a private hospital and the other one a state hospital and compares these two indices with a questionnaire.

To provide environmentally friendly services, customers and environmental criteria have to be taken into account in the decision-making process and distributing the Green Quality Function provides a very useful way to achieve this goal.

Open access
X-ray photoelectron spectroscopy (XPS) study of Heusler alloy (Co2FeAl) interfaced with semiconductor (n-Si) structure

Abstract

Layered magnetic heterostructures are very promising candidates in spintronics in which the influences of interfaces, surfaces and defects play a crucial role. X-ray photoelectron spectroscopy (XPS) study has been performed for studying in detail the chemical state and electronic structure of Co2FeAl (CFA) Heusler alloy interfaced with Si substrates. XPS survey scan spectra have clearly shown the presence of Fe, Co and Al signal along with the signal due to Si. The presence of Co, Fe and Al signal confirms the formation of CFA alloy phase. Our XPS results support our previous study [1] on CFA/Si structure in determining the magnetic and transport properties across the interface.

Open access
Analysis of Systems Ensuring the Acquisition of Real-Time Cartographic Navigation Information

Abstract

Electronic Chart Display and Information Systems (ECDIS), which are used on vessels and can replace paper charts, allow to obtain and display on electronic charts information from basic and additional data sources. For the certified use of ECDIS instead of paper charts, it is necessary to ensure constant updating of Electronic Navigation Chart (ENC) data provided to vessels for use. The known visual and satellite observation systems intended for cartographic information update are costly, have low accuracy and do not allow to quickly update navigational charts in real-time mode. The stand-alone use of remotely piloted aircraft (RPA) will make it possible not only to substantially reduce costs and increase the accuracy of monitoring, but also to provide information in real-time mode.

Open access
Risk Assessment of the Adverse Events in Air Transportation

Abstract

In the field of security in transport distinguish risks related to flight safety and aviation security. Safety of flights is ensured through the reliability of aviation equipment and the qualification of the personnel who services and operates it, aviation security is a condition of protection from illegal interference in its activity. Risk management in civil aviation in the field of security is a relatively new direction of activity. Deep research in this area began only at the beginning of the XXI century. It is quite difficult to use the existing experience of risk management, accumulated in other spheres, as civil aviation has significant features. Various methods and schemes can be used to assess risks. The article discusses various options for predicting risks using the “event tree” and “risk factor tree” methods.

Open access
RPAS Satellite Communication Channel Based on IEEE 802.11b Standard

Abstract

Original models of RPAS communication channels based on IEEE 802.11b Standard, including both Base Station transmission within the Radio Line of Sight, and through the satellite using Beyond Radio Line of Sight, were built. Dependencies of the Bit Error Rate on the Signal-Noise Ratio for different payload data rates were obtained. Transponder nonlinearity and Base Station antenna diameter impact were analysed.

Open access