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A Quality Assurance Model for airborne Safety-Critical Software

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Journal of Software Engineering and Applications 2014年第3期7卷 162-176页

作者： Nadia Bhuiyan Habib A. ElSabbagh Departmentof Mechanical and Industrial Engineering Concordia University Montreal Canada Xmile Inc. Montreal Canada

The tragic nature of safety-critical software failure’s consequences makes high quality and extreme reliability requirements in such types of software of paramount importance. Far too many accidents have been caused by software failure error or where such failure/error was part of the problem. Safety-critical software is widely applied in diverse areas, ranging from medical equipment to airborne systems. Currently, the trend in the use of safety-critical software in the aerospace industry is mostly concentrated on avionic systems. While standards for certification and development of safety-critical software have been developed by authorities and the industry, very little research has been done to address safety-critical software quality. In this paper, we study safety-critical software embedded in airborne systems. We propose a lifecycle specially modeled for the development of safety-critical software in compliance with the DO-178B standard and a software quality assurance (SQA) model based on a set of four acceptance criteria that builds quality into safety-critical software throughout its development.

关键词： Safety-Critical Software Software Quality Assurance airborne Systems

ON CLUTTER DOF FOR PHASED ARRAY airborne EARLY ARNING RADARS

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Journal of Electronics(China) 1993年第4期10卷 307-314页

作者：廖桂生保铮张玉洪 Institute of Electronic Engineering Xidian UniversityXi'an 710071

In recent years,considerable attention has been paid to adaptive clutter suppressionfor airborne early warning(AEW)radars.A necessary condition for efficient clutter suppressionis that the number of adaptive degrees of freedom(DOF)is no less than that of clutter *** paper analyzes the DOF of clutter for phased array AEW *** new results obtainedhere are helpful to design an adaptive system for clutter suppression.

关键词： airborne radars Clutter suppression Adaptive spatial-temporal processing

SPACE-TIME ADAPTIVE PROCESSING FOR airborne RADAR:A CONVENIENT IMPLEMENTATION APPROACH

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Journal of Electronics(China) 1996年第4期13卷 310-318页

作者： Wang Yongliang Peng Yingning(Dept. of Electronic Engineering, Tsinghua University, Beijing, 100084) Dept. of Electronic Engineering Tsinghua University Beijing

A convenient implementation approach to space-time adaptive processing for airborne radar has been proposed, which is added by some auxiliary array elements in the area of main-lobe clutter on the basis of 2-D Capon approach . It is of practical use for its small computational load. This approach possesses the ideal performance in the area of main-lobe clutter . In addition, the approach which is added by some auxiliary beams in the area of main-lobe clutter has also been discussed.

关键词： airborne radar Space-time adaptive processing(STAP) Clutter suppression

Climatological Analysis of Aerosols Optical Properties by airborne Sensors and in Situ Measurements in West Africa: Case of the Sahelian Zone

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Open Journal of Air Pollution 2019年第4期8卷 118-135页

作者： Nébon Bado Adama Ouédraogo Hassime Guengané Thierry Sikoudouin Maurice Ky Serge Dimitri Bazyomo Bruno Korgo Mamadou Simina Dramé Saidou Moustapha Sall Florent P. Kieno Dieudonné Joseph Bathiebo Laboratoire d’Energies Thermiques Renouvelables (L.E.T.RE) Université Joseph Ki Zerbo Ouaga Burkina Faso Laboratoire de Physique de l’Atmosphère et de l’Océan Siméon Fongang Université Cheikh Anta Diop Dakar-Fann Sénégal Centre Universitaire Polytechnique de Kaya (CUP-K) Kaya Burkina Faso Institute of Mathematics and Physical Sciences University of Abomey-Calavi Porto-Novo Benin

This paper deals with the climatology of aerosols in West Africa based on satellite and in situ measurements between 2001 and 2016 and covers four sites in the Sahelian zone. There are indeed Banizoumbou (13.541°N, 02.665°E), Cinzana (13.278°N, 05.934°W), Dakar (14.394°N, 16.959°W) and Ouagadougou (12.20°N, 1.40°W) located respectively in Niger, Mali, Senegal and Burkina Faso. Thus, an intercomparison between the satellite observations and the in situ measurements shows a good correlation between MODIS and AERONET with a correlation coefficient R = 0.86 at Cinzana, R = 0.85 at Banizounbou, R = 0.84 at Ouagadougou and a low correlation coefficient R = 0.66 calculated on the Dakar site. Like MODIS, SeaWiFS shows a very good correspondence with measurements of the ground photometer especially for Banizoumbou (R = 0.89), Cinzana (R = 0.88) and Dakar (R = 0.75) followed by a low correlation coefficient calculated on the Ouagadougou site (R = 0.64). The performance of these airborne sensors is also corroborated by the calculation of root mean square error (RMSE) and the mean absolute error (MAE). Following this validation, a climatological analysis based on aerosol optical depth (AOD) shows the seasonality of aerosols in West Africa strongly influenced by the climate dynamics illustrated by the MERRA model reanalysis. This seasonal spatial distribution of aerosols justifies the temporal variability of the particles observed at the different sites in the Sahel. In addition, a combined analysis of AOD and Angstrom coefficient indicates the aerosol period in the Sahel in spring (March-April-May) and summer (June-July-August). However, these aerosols are strongly dominated by desert dust whose main sources are located north in the Sahara and Sahel.

关键词： West-Africa Aerosols airborne Sensors Aeronet MERRA Model

Embedded System Implementation of airborne Communication Terminals

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Wireless Engineering and Technology 2013年第3期4卷 139-144页

作者： Lei Wang Zhizhong Ding Rui Huang Qian Li Hesheng Cheng Department of Communication Engineering Hefei University of Technology Hefei Department of Communication Engineering Hefei University of Technology Hefei China Department of Computer Science and Technology Hefei Normal University Hefei China.

airborne communication terminal is a key unit in Ad hoc network of aircrafts. This paper mainly focuses on its implementation by embedded system, which is based on Samsung S3C2410 chip. System architecture, Linux tailoring and touch-screen driver design are discussed in detail. Considering the requirements of stability and efficiency of the operating system, dynamic driver-loading method was employed firstly and only the necessary library files were transplanted to assist and test. The drivers finally were directly put into kernel configuration and then an integrated kernel was transplanted. Regarding to the problem of positioning issues on touch-screen, which is implemented in this system, an accurate positioning method is also presented.

关键词： airborne Communication Terminal Ad Hoc Network Embedded System Touch-Screen

Estimating Individual Tree Diameter and Stem Volume Using airborne LiDAR in Saga Prefecture, Japan

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Open Journal of Forestry 2018年第2期8卷 205-228页

作者： Katsumasa Oono Satoshi Tsuyuki Department of Global Agricultural Sciences The University of Tokyo Tokyo Japan Forest & Agriculture Solution Department Asia Air Survey CO. LTD. Kanagawa Japan

Advancements in airborne LiDAR analysis technology have made it possible to quantify forest resource volumes based on individual trees, and such technology may soon replace field surveys. Unlike individual tree detection or tree height measurements, diameter at breast height (DBH) is difficult to determine directly from measured data and is instead estimated indirectly using the correlation between crown size and DBH. Indicators that represent crown size include crown area, surface area, length, and length ratio, and were utilized with tree height as explanatory variables in ten combinations to determine a regression formula. DBH and tree height calculated from the regression formula were applied to an equation to calculate stem volumes of individual trees. airborne LiDAR measurements were taken using ALS50-II and ALS60 (Leica) at a density of 4 points/m2. An evaluation of the relationship between the regression formulae and DBH estimates indicated that a combination of crown area, tree height, and crown ratio for Japanese cedar, and a combination of crown area and tree height for Japanese cypress, yielded the highest coefficients of determination. The average error and RMSE were 6.9% and 2.38 cm respectively for Japanese cedar, while the corresponding values for Japanese cypress were 8.35% and 2.51 cm. Once the relationship was extended to the stem volumes of individual trees, the average error was 14.4% and RMSE was 0.10 m3 for Japanese cedar. The corresponding values for Japanese cypress were 18.9% and 0.10 m3. These results demonstrate the potential use of airborne LiDAR as a substitute for field surveys.

关键词： airborne LiDAR Diameter at Breast Height Individual Treevolume Forest Resource Individual-Tree-Based Approach

Massively Deployable, Low-Cost airborne Sensor Motes for Atmospheric Characterization

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Wireless Sensor Network 2020年第1期12卷 1-11页

作者： Michael Bolt J. Craig Prather Tyler Horton Mark Adams Department of Electrical and Computer Engineering Auburn University Auburn AL USA

A low-cost airborne sensor mote has been designed for deployment en masse to characterize atmospheric conditions. The designed environmental sensing mote, or eMote, was inspired by the natural shape of auto-rotating maple seeds to fall slowly and gather data along its descent. The eMotes measure and transmit temperature, air pressure, relative humidity, and wind speed estimates alongside GPS coordinates and timestamps. Up to 2080 eMotes can be deployed simultaneously with a 1 Hz sampling rate, but the system capacity increases by 2600 eMotes for every second added between samples. All measured and reported data falls within accuracy requirements for reporting with both the World Meteorological Organization (WMO) and the National Oceanic and Atmospheric Administration (NOAA). This paper presents the design and validation of the eMote system alongside discussions on the implementation of a large-scale, low-cost sensor network. The eMote represents unprecedented in-situ atmospheric measurement capabilities with the ability to deploy more than 260 times the number of sensing units as the most comparable commercially available dropsonde.

关键词： Atmospheric Sensing airborne Biomimetic MF-TDMA

Analysis of Changing Factors on airborne Allergenic Pollens Distribution in Taiyuan Downtown, North China

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International Journal of Otolaryngology and Head & Neck Surgery 2015年第2期4卷 148-155页

作者： Kejun Zhang Binquan Wang Yanli Zhang Yanli Zhang Nasha Cheng Changsheng Wang Chunming Zhang Wei Gao Ganggang Chen Department of Otolaryngology Head and Neck Surgery First Hospital Shanxi Medical University Taiyuan China

To study and analyse 2 surveys on airborne allergenic pollens distribution in Taiyuan Downtown, North China 30 years apart, the surveys focused on the phenomenon and the influence factors on types, counts, drift patterns, growth and decline rhythm and distribution features of airborne pollen with the same methods in the region in March 1977 to February 1978 and July 2008 to June 2009, respectively. The data of two airborne pollens surveys were treated with statistics, comparation and analysis, and the influence factors of pollen distribution in Taiyuan Downtown were explored. In the 2 surveys, 24 species and 35 species of pollen were collected in the region, respectively. Two pollen drift peaks were formed in spring and autumn in the two surveys. Artemisia L. is still the absolute dominant allergy airborne pollen. The types, counts, drift patterns and composition of pollen in air could be changed by the plants variation. Climate warming might affect pollen peak appearing time and lasting time, climate warming and Poplar & Willow contents changes in spring and autumn reversed the airborne pollen peak. It was found that Humulus L. had become the region’s main allergic pollen. Invasive strong allergen ragweed was spread to the inland city Taiyuan. Allergists should focus on exotic invasive harmful plants in the region.

关键词： airborne Pollen Identification of Pollen Pollen Count Seasonal Distribution of airborne Pollen Taiyuan

Comparative Analysis of the Digital Terrain Models Extracted from airborne LiDAR Point Clouds Using Different Filtering Approaches in Residential Landscapes

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Advances in Remote Sensing 2019年第2期8卷 51-75页

作者： Fahmy F. F. Asal Civil Engineering Department Faculty of Engineering Menoufia University Shebin El-Kom Egypt

Light Detection And Ranging (LiDAR) is a well-established active remote sensing technology that can provide accurate digital elevation measurements for the terrain and non-ground objects such as vegetations and buildings, etc. Non-ground objects need to be removed for creation of a Digital Terrain Model (DTM) which is a continuous surface representing only ground surface points. This study aimed at comparative analysis of three main filtering approaches for stripping off non-ground objects namely;Gaussian low pass filter, focal analysis mean filter and DTM slope-based filter of varying window sizes in creation of a reliable DTM from airborne LiDAR point clouds. A sample of LiDAR data provided by the ISPRS WG III/4 captured at Vaihingen in Germany over a pure residential area has been used in the analysis. Visual analysis has indicated that Gaussian low pass filter has given blurred DTMs of attenuated high-frequency objects and emphasized low-frequency objects while it has achieved improved removal of non-ground object at larger window sizes. Focal analysis mean filter has shown better removal of nonground objects compared to Gaussian low pass filter especially at large window sizes where details of non-ground objects almost have diminished in the DTMs from window sizes of 25 × 25 and greater. DTM slope-based filter has created bare earth models that have been full of gabs at the positions of the non-ground objects where the sizes and numbers of that gabs have increased with increasing the window sizes of filter. Those gaps have been closed through exploitation of the spline interpolation method in order to get continuous surface representing bare earth landscape. Comparative analysis has shown that the minimum elevations of the DTMs increase with increasing the filter widow sizes till 21 × 21 and 31 × 31 for the Gaussian low pass filter and the focal analysis mean filter respectively. On the other hand, the DTM slope-based filter has kept the minimum elevation of th

关键词： DSM/DEM/DTM airborne LiDAR Point Clouds DSM Filtering Gaussian Low Pass Filter Focal Analysis Mean Filter DTM Slope-Based Filter Removal of Non-Ground Objects