2013 International Conference on Aerospace Science & Engineering (ICASE)最新文献_第3页

Short term drought monitoring using remote sensing technique: A case study of Potohar region, Pakistan 利用遥感技术进行短期干旱监测:以巴基斯坦Potohar地区为例

2013 International Conference on Aerospace Science & Engineering (ICASE) Pub Date : 2013-08-01 DOI: 10.1109/ICASE.2013.6785571

Saad-ul-Haque, B. Ghauri, M. Khan

{"title":"Short term drought monitoring using remote sensing technique: A case study of Potohar region, Pakistan","authors":"Saad-ul-Haque, B. Ghauri, M. Khan","doi":"10.1109/ICASE.2013.6785571","DOIUrl":"https://doi.org/10.1109/ICASE.2013.6785571","url":null,"abstract":"Drought has frequently been witnessed in the country due to various environmental changes such as rise in atmospheric pollution and climatic changes. Pakistan is predominantly arid and semi-arid with a diversified climate, where agriculture contributes 20.9 percent to national GDP. The Barani (rainfed) land covering Salt Range and Potohar Plateau (about 22,256 km2 centered at 33.2° N and 72.75° E, at an elevation of 1,200 to 1,900 feet ASL). This area is more vulnerable to short term droughts with mean monthly rainfall in this area ranges from 30 to 200 mm with max. temperature up to 47 °C. Solar radiation (over 3,000 hours of sunshine/year) results in higher rate of evapo-transpiration. Such conditions and prolonged absence of regular rainfall lead to drought conditions affecting crop yield and economy of the country. NDVI product of MODIS Satellite was used for Rabi season (October to February) in order to investigate vegetation state and effects of drought on these crop. Soil Moisture data was incorporated to analyze water deficit pattern using NCEP global weather data from 2000-2012. The results showed that, there was a drastic decrease in mean NDVI during 2009-2010 winters' months due to low rainfall. This decrease in NDVI value seen from 2.2 in 2009-2010 as compared to average mean value of 2.9 for 2000-2012 of winter Monsoon months. Such relationship would help devise an early warning system to detect the onset of drought conditions and developing a continuous drought monitoring system. Based on such studies, future strategies for water management, mitigations could be worked out, such as preservation of water during summer monsoons to overcome the water stress in the coming winter season.","PeriodicalId":155651,"journal":{"name":"2013 International Conference on Aerospace Science & Engineering (ICASE)","volume":"282 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2013-08-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"122948026","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 8

Modular & COTS based power system for small LEO satellite 基于模块化和COTS的小型LEO卫星电源系统

2013 International Conference on Aerospace Science & Engineering (ICASE) Pub Date : 2013-08-01 DOI: 10.1109/ICASE.2013.6785558

S. M. Adnan, Muhammad Shahid Bhutto

引用次数: 2

Spatio temporal behavior of AOD over Pakistan using MODIS data 利用MODIS数据分析巴基斯坦上空AOD的时空特征

2013 International Conference on Aerospace Science & Engineering (ICASE) Pub Date : 2013-08-01 DOI: 10.1109/ICASE.2013.6785568

Anam Ashraf, Neelam Aziz, Sheikh Saeed Ahmed

{"title":"Spatio temporal behavior of AOD over Pakistan using MODIS data","authors":"Anam Ashraf, Neelam Aziz, Sheikh Saeed Ahmed","doi":"10.1109/ICASE.2013.6785568","DOIUrl":"https://doi.org/10.1109/ICASE.2013.6785568","url":null,"abstract":"Aerosols are solid or liquid particles suspended in the atmosphere coming from both natural and anthropogenic sources, they are distributed through wind currents to the places even where they are not formed. Hence, atmospheric aerosols have varying spatial and temporal concentration on both regional and global scale. They play a very vital role in regulating climate by modifying earth's radiative budget through the absorption and scattering of solar radiations. Moreover it also affects environmental status of region at both local and regional scale like visibility and air pollution. Satellite remote sensing is a potential source for monitoring air pollution. In order to access aerosol volume concentration over Pakistan at temporal and spatial scale, attribute data from Terra-MODIS satellite for AOD550 nm was downloaded for years 2007-2011. Maps were generated to identify hotspots by using Arc GIS 9.3 for the time scale of 2007-2011. Furthermore, backward trajectories were also calculated from NOAA HYSPLIT model at the height of 500, 1000, and 1500 meter for different locations over Pakistan. It was observed that aerosol concentration of coarse mode particles increases in the season of monsoon due to high dust storm frequency, burning activities in the agricultural fields of Pakistan and India (Indian Gigantic Plain) and due to the transportation of particles from the neighboring countries. It was observed that 2008 was highly polluted year as it had the highest concentration of aerosols throughout the year. Aerosol optical density (AOD) values and visibility was plotted and it was observed that it reduced considerably in years 2007-2011 with increasing AOD concentration.","PeriodicalId":155651,"journal":{"name":"2013 International Conference on Aerospace Science & Engineering (ICASE)","volume":"112 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2013-08-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"124729361","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 7

An efficient image buffering and tiling algorithm for multiple channel image acquisition for space missions 一种用于空间任务多通道图像采集的高效图像缓冲和平铺算法

2013 International Conference on Aerospace Science & Engineering (ICASE) Pub Date : 2013-08-01 DOI: 10.1109/ICASE.2013.6785570

Naveed Ahmed, A. Khan

{"title":"An efficient image buffering and tiling algorithm for multiple channel image acquisition for space missions","authors":"Naveed Ahmed, A. Khan","doi":"10.1109/ICASE.2013.6785570","DOIUrl":"https://doi.org/10.1109/ICASE.2013.6785570","url":null,"abstract":"Most modern imaging satellites are required to acquire images that are of high pixel resolution as well as a large swath width. These two parameters combined with usage of multiple sensor streams tend to increase the volume of data that must be transmitted to the ground. On the other hand most image compression algorithms require image data in form of small tiles. These requirements call for an efficient image buffering and tiling algorithm that can accommodate high input data rates, perform image tiling according to the requirement of compression, and preserve data continuity. This paper presents a new image buffering and tiling mechanism for image acquisition unit of imaging satellites. The presented design achieves high data throughput and is therefore capable of acquiring high resolution images from multiple sensor channels, while preventing data loss. The design has been implemented on a high speed processing unit based on field programmable gate array (FPGA) which interfaces with an external memory which is used as a FIFO buffer for writing image data in linear form and reading out in tiled form. The tile size is a run-time customizable parameter. Analysis has been performed for the effect of different parameters including image resolution in terms of ground sampling distance, and number of channels on the design performance. The design is capable of acquiring high resolution image data from multiple sensor channels while tiling out the data without data loss.","PeriodicalId":155651,"journal":{"name":"2013 International Conference on Aerospace Science & Engineering (ICASE)","volume":"16 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2013-08-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"117049323","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 3

Comparison survey of 4G competitors (OFDMA, MC CDMA, UWB, IDMA) 4G竞争对手对比调查(OFDMA、mccdma、UWB、IDMA)

2013 International Conference on Aerospace Science & Engineering (ICASE) Pub Date : 2013-08-01 DOI: 10.1109/ICASE.2013.6785555

K. Khurshid, I. Khokhar

引用次数: 9

Methodologies for preliminary design of variable wing geometry aircraft 变翼几何飞机的初步设计方法

2013 International Conference on Aerospace Science & Engineering (ICASE) Pub Date : 2013-08-01 DOI: 10.1109/ICASE.2013.6785549

Shehryar Ishtiaq, A. Israr

引用次数: 0

Reinforcement effect of nanodiamond on properties of epoxy matrix 纳米金刚石对环氧基材料性能的增强作用

2013 International Conference on Aerospace Science & Engineering (ICASE) Pub Date : 2013-06-01 DOI: 10.1002/PC.22480

S. A. Rakha, A. A. Khurram, T. Subhani, N. Ali, A. Munir

{"title":"Reinforcement effect of nanodiamond on properties of epoxy matrix","authors":"S. A. Rakha, A. A. Khurram, T. Subhani, N. Ali, A. Munir","doi":"10.1002/PC.22480","DOIUrl":"https://doi.org/10.1002/PC.22480","url":null,"abstract":"Epoxy/nanocrystalline diamond nanocomposites composites were prepared by dispersing ultrasonically, 0.4, 0.7, 1.0, and 4.0 wt. % acid treated nanocrystalline diamond (NCD) powder in epoxy matrix. Fourier infrared spectroscopy was utilized to study the moieties attached to the nanodiamond particles. The trace elements present in NCD powder before and after acid treatment were analyzed using ion beam techniques. Thermo-mechanical properties of the nanocomposites showed that incorporation of low content (0.4 wt. %) of nanodiamond powder into epoxy matrix enhanced the storage modulus, loss modulus and hardness by ~68%, ~55% and ~86% respectively over neat epoxy. By increasing the concentration of modified NCD to 0.7 wt. % resulted in lower values of hardness and thermo-mechanical properties but still remain higher than neat epoxy. An increasing trend in properties was again observed at 4 wt. % concentration of modified nanofiller. The improvement in storage modulus, loss modulus and hardness was ~57%, 105% and 70% respectively. The glass transition temperature was up shifted to ~110°C over neat epoxy. The mechanisms responsible for enhanced properties of epoxy matrix are also discussed in detail.","PeriodicalId":155651,"journal":{"name":"2013 International Conference on Aerospace Science & Engineering (ICASE)","volume":"59 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2013-06-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"121437113","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 33