Pub Date : 2017-11-01DOI: 10.1109/ICASE.2017.8374274
Javairia Shabnum, S. Ahmad
Medical geography helps to quickly expose data base development, analyzing, modeling, mapping and visualization of data. Present study was aimed to provide data to public health authorities for allocation of resources and prevention of disease in high risk areas. Data related to diseased people was requested from District Health Office Rawalpindi for all the tehsils of Rawalpindi district on monthly basis from 2011–2015. Topographic map of the study area was purchased from Geological Survey of Pakistan where as health facilities locations were recorded using Trimble Nomad 900 receiver and also cross checked by importing it on Google EarthTM for accuracy assessment. Different geo-statistical tools were applied to check the pattern of disease using ArcGIS. Negative values of Moran' I statistic showed random distribution pattern in District Rawalpindi where as Anselin local Moran's I statistic identify the spatial outliers in data for Viral Hepatitis which were Rhc-Kotli Sattian and Bagga Shaikhan from 2011–2015 in Rawalpindi district. Getis-Ord Gi∗ statistic showed hot spots in Rawalpindi, Kotli Sattian and Muree tehsils. Centrographic statistics showed that spread of the disease is from South-West to North-East. This study proposed that there is a serious need to analyze the spatial outlier areas and hotspots to identify the causing agents and to take immediate steps for control of high outbreak of Viral Hepatitis.
{"title":"Surveillance of viral hepatitis by using geostatistical tools in district Rawalpindi","authors":"Javairia Shabnum, S. Ahmad","doi":"10.1109/ICASE.2017.8374274","DOIUrl":"https://doi.org/10.1109/ICASE.2017.8374274","url":null,"abstract":"Medical geography helps to quickly expose data base development, analyzing, modeling, mapping and visualization of data. Present study was aimed to provide data to public health authorities for allocation of resources and prevention of disease in high risk areas. Data related to diseased people was requested from District Health Office Rawalpindi for all the tehsils of Rawalpindi district on monthly basis from 2011–2015. Topographic map of the study area was purchased from Geological Survey of Pakistan where as health facilities locations were recorded using Trimble Nomad 900 receiver and also cross checked by importing it on Google EarthTM for accuracy assessment. Different geo-statistical tools were applied to check the pattern of disease using ArcGIS. Negative values of Moran' I statistic showed random distribution pattern in District Rawalpindi where as Anselin local Moran's I statistic identify the spatial outliers in data for Viral Hepatitis which were Rhc-Kotli Sattian and Bagga Shaikhan from 2011–2015 in Rawalpindi district. Getis-Ord Gi∗ statistic showed hot spots in Rawalpindi, Kotli Sattian and Muree tehsils. Centrographic statistics showed that spread of the disease is from South-West to North-East. This study proposed that there is a serious need to analyze the spatial outlier areas and hotspots to identify the causing agents and to take immediate steps for control of high outbreak of Viral Hepatitis.","PeriodicalId":203936,"journal":{"name":"2017 Fifth International Conference on Aerospace Science & Engineering (ICASE)","volume":"3 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2017-11-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"128801760","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}
Pub Date : 2017-11-01DOI: 10.1109/ICASE.2017.8374259
Jawad Ullah, R. S. Choudhry, H. Saeed
Numerical model for prediction of progressive delamination in woven fabric reinforced composite is proposed in this paper. An orthotropic model is used in which the interface is modeled as bilinear cohesive zone elements subjected to mixed mode loadings. The mixed mode loading is applied through displacements. Mesh insensitive model is obtained at a converged mesh. Mass scaling is used to run the model at high mesh density and the results are accurately found. Effect of displacement rate is studied. Load displacements graphs are obtained, and they agreed with the experimental load displacements graphs.
{"title":"Numerical simulation of delamination under mixed mode loading of woven fabric reinforced composites through cohesive zone elements","authors":"Jawad Ullah, R. S. Choudhry, H. Saeed","doi":"10.1109/ICASE.2017.8374259","DOIUrl":"https://doi.org/10.1109/ICASE.2017.8374259","url":null,"abstract":"Numerical model for prediction of progressive delamination in woven fabric reinforced composite is proposed in this paper. An orthotropic model is used in which the interface is modeled as bilinear cohesive zone elements subjected to mixed mode loadings. The mixed mode loading is applied through displacements. Mesh insensitive model is obtained at a converged mesh. Mass scaling is used to run the model at high mesh density and the results are accurately found. Effect of displacement rate is studied. Load displacements graphs are obtained, and they agreed with the experimental load displacements graphs.","PeriodicalId":203936,"journal":{"name":"2017 Fifth International Conference on Aerospace Science & Engineering (ICASE)","volume":"50 5 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2017-11-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"128003595","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}
Pub Date : 2017-11-01DOI: 10.1109/ICASE.2017.8374256
S. Amjad, N. Khan
In this work the vibration analysis of viscoelastic composite panels of engine in propeller aircraft has been carried out. Both analytical and numerical (Finite Element) analysis has been carried out. Engine Panels are similar to plates. So, analytical formulation of the plate has been carried out to find out the vibrational response for specially orthotropic composite panel. As the solution of equilibrium equations for general laminates with any stacking sequence cannot be obtained analytically. Therefore, numerical method technique (Finite Element Analysis) is then employed to find out the vibrational characteristics of the panel. By carrying out modal analysis it is found out that the natural frequencies of the composite panel became higher by the inclusion of viscoelastic layers. So, increase in the natural frequencies will be advantageous in engine cowling panels. It is also observed that for panels with and without viscoelastic laminas, the deflection patterns are quite similar. However, as the natural frequencies of the panel without viscous effects are lower, so therefore deflection of the central node occurred earlier. Furthermore, a very small decrease in the transverse deflection of the node is seen for viscoelastic panel. A phase shift is also observed. Transient analysis revealed that all composite panels exhibit damping characteristics to an impulse force. However, damping effect is prominent in panels with viscoelastic laminas.
{"title":"Vibration analysis of viscoelastic composite panels of engine cowling in propeller aircraft using analytical & numerical methods","authors":"S. Amjad, N. Khan","doi":"10.1109/ICASE.2017.8374256","DOIUrl":"https://doi.org/10.1109/ICASE.2017.8374256","url":null,"abstract":"In this work the vibration analysis of viscoelastic composite panels of engine in propeller aircraft has been carried out. Both analytical and numerical (Finite Element) analysis has been carried out. Engine Panels are similar to plates. So, analytical formulation of the plate has been carried out to find out the vibrational response for specially orthotropic composite panel. As the solution of equilibrium equations for general laminates with any stacking sequence cannot be obtained analytically. Therefore, numerical method technique (Finite Element Analysis) is then employed to find out the vibrational characteristics of the panel. By carrying out modal analysis it is found out that the natural frequencies of the composite panel became higher by the inclusion of viscoelastic layers. So, increase in the natural frequencies will be advantageous in engine cowling panels. It is also observed that for panels with and without viscoelastic laminas, the deflection patterns are quite similar. However, as the natural frequencies of the panel without viscous effects are lower, so therefore deflection of the central node occurred earlier. Furthermore, a very small decrease in the transverse deflection of the node is seen for viscoelastic panel. A phase shift is also observed. Transient analysis revealed that all composite panels exhibit damping characteristics to an impulse force. However, damping effect is prominent in panels with viscoelastic laminas.","PeriodicalId":203936,"journal":{"name":"2017 Fifth International Conference on Aerospace Science & Engineering (ICASE)","volume":"9 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2017-11-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"133691002","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}
Pub Date : 2017-11-01DOI: 10.1109/ICASE.2017.8374263
S. Memon, Hungsun Son, Sana Ahmed, Awais Ali Memon
The proposed integrated track split (ITS) smoothing utilize smoothing data association algorithm for tracking a target. We implemented two independent ITS filters; forward running ITS (fITS) filter and backward running ITS (bITS) filter. The novelty of the proposed algorithm is that the backward multi-track component predictions are applied to each forward track component prediction to produce multiple information fusion component predictions based on the data association technique. The information fusion state predictions are applied to all available measurements received in current scan to smooth track state estimations and target existence probabilities. A new technique is developed which applies smoothing estimates to compute the fITS estimate in the current scan. This efficiently leads forward path track to track a target in heavy clutter. The algorithm is known as fixed-interval smoothing ITS (FIsITS). The numerical simulation verifies the false track discrimination (FTD) capability of the FIsITS.
{"title":"Track split smoothing for target tracking in clutter","authors":"S. Memon, Hungsun Son, Sana Ahmed, Awais Ali Memon","doi":"10.1109/ICASE.2017.8374263","DOIUrl":"https://doi.org/10.1109/ICASE.2017.8374263","url":null,"abstract":"The proposed integrated track split (ITS) smoothing utilize smoothing data association algorithm for tracking a target. We implemented two independent ITS filters; forward running ITS (fITS) filter and backward running ITS (bITS) filter. The novelty of the proposed algorithm is that the backward multi-track component predictions are applied to each forward track component prediction to produce multiple information fusion component predictions based on the data association technique. The information fusion state predictions are applied to all available measurements received in current scan to smooth track state estimations and target existence probabilities. A new technique is developed which applies smoothing estimates to compute the fITS estimate in the current scan. This efficiently leads forward path track to track a target in heavy clutter. The algorithm is known as fixed-interval smoothing ITS (FIsITS). The numerical simulation verifies the false track discrimination (FTD) capability of the FIsITS.","PeriodicalId":203936,"journal":{"name":"2017 Fifth International Conference on Aerospace Science & Engineering (ICASE)","volume":"24 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2017-11-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"132131649","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}
Pub Date : 2017-11-01DOI: 10.1109/ICASE.2017.8374244
N. Naqvi, F. Ahmed, U. Ahmed, D. Amin
In the light of current need of space exploration and development of space nation, the purpose of this paper is to discuss the impact of unified pedagogy on diverse audience to result in suitable framework for future steering of Space Technology Education and Popularization (STEP) across Pakistan. This paper also highlights deficiencies of current curriculum and emphasize the development of objective based education curriculum for technical courses. The said paper uses current curriculum, case study and control group comparative quantitative research for development of unified pedagogy for Space Technology and Education Popularization. The paper also highlights the effect of unified pedagogy on steering and thought processing ability of audiences as through standard feedback approach. Unified pedagogy using traditional lectures, webinars, hands on trainings, workshops and demonstrations is considered in this paper for making an impact on space technology knowledge among participants. The paper demonstrates the successful usage of unified pedagogy and role of subject matter experts in curriculum development. The paper also indicates training and relevance of facilitators to the field is as important as the curriculum itself. The unification of theoretical knowledge and practical implication also results in better concept creation and improves the motor learning skills. The paper presents the overall usage of unified pedagogy in development of space nation, however this is limited to a specific time frame and uses current most advanced methodologies. The analysis of the need, pedagogical methods used, development of the curriculum and trained subject matter experts as facilitators are instructive. These will provide valuable pointers for policy makers in futuristic steering of Space Technology Education and Popularization across the country. It also provides an insight to the futuristic human resource development from grass root level with sound theoretical, scientific and technical foundation to strive more.
{"title":"Unification of traditional and scientific pedagogy in Space Technology Education and Popularization (STEP): Space summer school — A case study","authors":"N. Naqvi, F. Ahmed, U. Ahmed, D. Amin","doi":"10.1109/ICASE.2017.8374244","DOIUrl":"https://doi.org/10.1109/ICASE.2017.8374244","url":null,"abstract":"In the light of current need of space exploration and development of space nation, the purpose of this paper is to discuss the impact of unified pedagogy on diverse audience to result in suitable framework for future steering of Space Technology Education and Popularization (STEP) across Pakistan. This paper also highlights deficiencies of current curriculum and emphasize the development of objective based education curriculum for technical courses. The said paper uses current curriculum, case study and control group comparative quantitative research for development of unified pedagogy for Space Technology and Education Popularization. The paper also highlights the effect of unified pedagogy on steering and thought processing ability of audiences as through standard feedback approach. Unified pedagogy using traditional lectures, webinars, hands on trainings, workshops and demonstrations is considered in this paper for making an impact on space technology knowledge among participants. The paper demonstrates the successful usage of unified pedagogy and role of subject matter experts in curriculum development. The paper also indicates training and relevance of facilitators to the field is as important as the curriculum itself. The unification of theoretical knowledge and practical implication also results in better concept creation and improves the motor learning skills. The paper presents the overall usage of unified pedagogy in development of space nation, however this is limited to a specific time frame and uses current most advanced methodologies. The analysis of the need, pedagogical methods used, development of the curriculum and trained subject matter experts as facilitators are instructive. These will provide valuable pointers for policy makers in futuristic steering of Space Technology Education and Popularization across the country. It also provides an insight to the futuristic human resource development from grass root level with sound theoretical, scientific and technical foundation to strive more.","PeriodicalId":203936,"journal":{"name":"2017 Fifth International Conference on Aerospace Science & Engineering (ICASE)","volume":"4 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2017-11-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"117138098","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}
Pub Date : 2017-11-01DOI: 10.1109/ICASE.2017.8374280
Muhammad Orangzeb
Applications of Synthetic Aperture Radar (SAR) data in the civic sector are rapidly growing. It is being used in flood monitoring, flood depth estimation, and flood extent mapping also. Seasonal independency makes SAR data more usable and effective in the monitoring of natural hazards and managing disasters. In this study, the potential of freely available moderate resolution sentinel-1A data were explored to map the flood extent by observing the strength of backscattering over the region of interest. Subsequently, Landsat-8 data were also used to accomplish the same task so that results could be compared. Chitral city, located in northern areas of Pakistan, was selected for this study, which had been experiencing frequent flooding. The flood of July 2015 was selected as the subject event. The Sentinel1-A and Landsat-8 images of pre, amid and post flood were downloaded. The hypothesis was tested that the SAR data would provide better results than the Optical data of Landsat-8, but the outcome of the study did not support the hypothesis and the results were totally inverse. The Independent Component Analysis (ICA) technique provided better and improved output with an area of 4.67 Sq. Kilometer under water from a total area of Chitral city (only) and its suburbs — which was estimated at around 26 Sq. Kilometer.
{"title":"Comparative analysis of flood extent mapping using sentinel-1A and Landsat-8 data","authors":"Muhammad Orangzeb","doi":"10.1109/ICASE.2017.8374280","DOIUrl":"https://doi.org/10.1109/ICASE.2017.8374280","url":null,"abstract":"Applications of Synthetic Aperture Radar (SAR) data in the civic sector are rapidly growing. It is being used in flood monitoring, flood depth estimation, and flood extent mapping also. Seasonal independency makes SAR data more usable and effective in the monitoring of natural hazards and managing disasters. In this study, the potential of freely available moderate resolution sentinel-1A data were explored to map the flood extent by observing the strength of backscattering over the region of interest. Subsequently, Landsat-8 data were also used to accomplish the same task so that results could be compared. Chitral city, located in northern areas of Pakistan, was selected for this study, which had been experiencing frequent flooding. The flood of July 2015 was selected as the subject event. The Sentinel1-A and Landsat-8 images of pre, amid and post flood were downloaded. The hypothesis was tested that the SAR data would provide better results than the Optical data of Landsat-8, but the outcome of the study did not support the hypothesis and the results were totally inverse. The Independent Component Analysis (ICA) technique provided better and improved output with an area of 4.67 Sq. Kilometer under water from a total area of Chitral city (only) and its suburbs — which was estimated at around 26 Sq. Kilometer.","PeriodicalId":203936,"journal":{"name":"2017 Fifth International Conference on Aerospace Science & Engineering (ICASE)","volume":"3 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2017-11-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"125162309","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}
Pub Date : 2017-11-01DOI: 10.1109/ICASE.2017.8374288
Saba Latif, N. Zafar
Internet of things (IoT) is collection of smart objects that senses real environment and gives response instantly while connected to a network. IoT and smart cities are implemented in every field of life including home, offices, healthcare centers, agriculture, waste management, transport management and environmental monitoring to make them smart. There are many benefits of implementing IoT in real environment but it raises various issues and challenges including security, privacy and heterogeneous nature of objects. Further, there is not any common communication standard for this purpose. Many traditional approaches are proposed by researchers which do not address these issues completely in a real sense. In this paper, we have presented a survey of existing work focusing on security and privacy issues in applications of IoT in smart cities. Finally, a problem is formulated based on identified issues for our future work.
{"title":"A survey of security and privacy issues in IoT for smart cities","authors":"Saba Latif, N. Zafar","doi":"10.1109/ICASE.2017.8374288","DOIUrl":"https://doi.org/10.1109/ICASE.2017.8374288","url":null,"abstract":"Internet of things (IoT) is collection of smart objects that senses real environment and gives response instantly while connected to a network. IoT and smart cities are implemented in every field of life including home, offices, healthcare centers, agriculture, waste management, transport management and environmental monitoring to make them smart. There are many benefits of implementing IoT in real environment but it raises various issues and challenges including security, privacy and heterogeneous nature of objects. Further, there is not any common communication standard for this purpose. Many traditional approaches are proposed by researchers which do not address these issues completely in a real sense. In this paper, we have presented a survey of existing work focusing on security and privacy issues in applications of IoT in smart cities. Finally, a problem is formulated based on identified issues for our future work.","PeriodicalId":203936,"journal":{"name":"2017 Fifth International Conference on Aerospace Science & Engineering (ICASE)","volume":"89 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2017-11-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"126497813","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}
Pub Date : 2017-11-01DOI: 10.1109/ICASE.2017.8374270
Saad Abbasi
In structural deformation monitoring especially of high-rise buildings our main aim is hunting and pin-pointing the deviations of structural movement from reference position (original) and to detect deviancy during normal conditions to catastrophic damage e.g windstorm, thunderstorm, explosion or earthquake. For that to happen an accurate, robust and reliable method for structural monitoring is needed. GNSS with its advanced augmentation techniques can give a positioning accuracy in order of millimetres at its best. Such a higher order of accuracy can be used for precise structural deformation monitoring. Apart from that GNSS gives us loathsome advantages like all weather, around the clock and global coverage. GNSS doesn't need line of sight as it was needed in previous techniques between its stations. Due to these benefits we are using GNSS technology for structural deformation monitoring. GNSS also has some drawbacks like the positioning accuracy is dependent up on number of available satellites, geometry of satellites, multipath and receiver noise. Un-affordable price of precise GNSS receivers also makes it tougher. The data used in the thesis is the one used for structural deformation monitoring with the help of base stations and the rovers using the real time kinematic RTK positioning logged at ICON Tower Karachi, Pakistan a high-rise building. RTKLIB a free software is used for analysis of logged data by applying stand-alone, differential code and differential carrier phase (RTK) positioning techniques. For our post-processing GPS data analysis we had used three rovers at three corners of building story under monitoring with common reference station. One by one on each of the sets we have RTK in RTKPOST GUI application of RTKLIB. For this analysis we have made three cases of comparison between individual RTK results of rover pairs and concluded deformation in a small chunk of time (3600 epochs) one hour data.
{"title":"Post-processing of GNSS data using open source software for structural deformation monitoring","authors":"Saad Abbasi","doi":"10.1109/ICASE.2017.8374270","DOIUrl":"https://doi.org/10.1109/ICASE.2017.8374270","url":null,"abstract":"In structural deformation monitoring especially of high-rise buildings our main aim is hunting and pin-pointing the deviations of structural movement from reference position (original) and to detect deviancy during normal conditions to catastrophic damage e.g windstorm, thunderstorm, explosion or earthquake. For that to happen an accurate, robust and reliable method for structural monitoring is needed. GNSS with its advanced augmentation techniques can give a positioning accuracy in order of millimetres at its best. Such a higher order of accuracy can be used for precise structural deformation monitoring. Apart from that GNSS gives us loathsome advantages like all weather, around the clock and global coverage. GNSS doesn't need line of sight as it was needed in previous techniques between its stations. Due to these benefits we are using GNSS technology for structural deformation monitoring. GNSS also has some drawbacks like the positioning accuracy is dependent up on number of available satellites, geometry of satellites, multipath and receiver noise. Un-affordable price of precise GNSS receivers also makes it tougher. The data used in the thesis is the one used for structural deformation monitoring with the help of base stations and the rovers using the real time kinematic RTK positioning logged at ICON Tower Karachi, Pakistan a high-rise building. RTKLIB a free software is used for analysis of logged data by applying stand-alone, differential code and differential carrier phase (RTK) positioning techniques. For our post-processing GPS data analysis we had used three rovers at three corners of building story under monitoring with common reference station. One by one on each of the sets we have RTK in RTKPOST GUI application of RTKLIB. For this analysis we have made three cases of comparison between individual RTK results of rover pairs and concluded deformation in a small chunk of time (3600 epochs) one hour data.","PeriodicalId":203936,"journal":{"name":"2017 Fifth International Conference on Aerospace Science & Engineering (ICASE)","volume":"26 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2017-11-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"130251091","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}
Pub Date : 2017-11-01DOI: 10.1109/ICASE.2017.8374277
Muhammad Athar Javaid, W. Keller
Gravity field recovery using space technology has evolved in the last two decades. Several dedicated satellite missions have been sent to the space to get more accurate and up-to-date gravity field information, including, Challenging Minisatellite Payload (CHAMP), Gravity Recovery and Climate Experiment (GRACE) and Gravity field and Ocean Circulation Explorer (GOCE), launched on 15 July 2000, 17 March 2002 and 17 March 2009, respectively. GRACE is the extended version of the CHAMP. CHAMP is an example of high-low satellite-to-satellite tracking (HL-SST) while the GRACE is an example of low-low satellite-to-satellite tracking (LL-SST) system. We study the gravity field in the form of SH coefficients using the range-rates observations from GRACE tandem satellites system. Sets of coefficients along with their standard deviation, recovered by GFZ-Germany up to degree and order 90 are available through the podaac data servers. In one month period, gravity field varies in few regions of the Earth. We observe it through the varying numerical values of few SH coefficients. In this contribution, we classify SH coefficients on the base of their information contents using artificial neural network (ANN) into two classes, one of them is the essential coefficient class which represents the varying gravity field and the other is the static coefficient class which does not have the varying gravity information. In the end we show that we can concentrate only on essential coefficients during the recovery process, rather than processing the whole set of coefficients.
{"title":"Data mining of spherical harmonic (SH) coefficients using artificial neural networks (ANN)","authors":"Muhammad Athar Javaid, W. Keller","doi":"10.1109/ICASE.2017.8374277","DOIUrl":"https://doi.org/10.1109/ICASE.2017.8374277","url":null,"abstract":"Gravity field recovery using space technology has evolved in the last two decades. Several dedicated satellite missions have been sent to the space to get more accurate and up-to-date gravity field information, including, Challenging Minisatellite Payload (CHAMP), Gravity Recovery and Climate Experiment (GRACE) and Gravity field and Ocean Circulation Explorer (GOCE), launched on 15 July 2000, 17 March 2002 and 17 March 2009, respectively. GRACE is the extended version of the CHAMP. CHAMP is an example of high-low satellite-to-satellite tracking (HL-SST) while the GRACE is an example of low-low satellite-to-satellite tracking (LL-SST) system. We study the gravity field in the form of SH coefficients using the range-rates observations from GRACE tandem satellites system. Sets of coefficients along with their standard deviation, recovered by GFZ-Germany up to degree and order 90 are available through the podaac data servers. In one month period, gravity field varies in few regions of the Earth. We observe it through the varying numerical values of few SH coefficients. In this contribution, we classify SH coefficients on the base of their information contents using artificial neural network (ANN) into two classes, one of them is the essential coefficient class which represents the varying gravity field and the other is the static coefficient class which does not have the varying gravity information. In the end we show that we can concentrate only on essential coefficients during the recovery process, rather than processing the whole set of coefficients.","PeriodicalId":203936,"journal":{"name":"2017 Fifth International Conference on Aerospace Science & Engineering (ICASE)","volume":"34 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2017-11-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"130571869","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}
Pub Date : 2017-11-01DOI: 10.1109/ICASE.2017.8374246
S. Salamat, Muneeb Ahsan, Irslan Arif
Thermoelectric generators have been used for space probe mission by NASA and other space agencies for a long time. These are absolutely indispensable for missions for Jupiter and beyond, where there is no solar radiation or no alternate source that could provide energy for these missions. Thermoelectrics convert heat directly into electricity. Seebeck coefficient is extremely important parameter in thermoelectric devices. On one hand it determines the open circuit voltage developed for thermoelectric generator, on the other hand, it also controls the magnitude of the Peltier coefficient responsible for thermoelectric cooling applications. When operating at wide range of temperature, not only the Fermi level changes, which needs to be taken into account, but the band gap changes with temperature, and therefore, causes the band edge to move and produces additional force on the carriers. The relations for Seebeck have a simpler form for non-degenerate semiconductor but become more complex for degenerate case. Besides, in small band gap materials (such as BiTe) as well as when operating over wide temperature range, the carrier of both signs (electrons and holes) may be present and therefore, bipolar effects need to be considered in these devices. Apart from traditional combination of parameters to solve for bipolar effects, we have developed our own algorithm, based on Landauer approach that can solve for seebeck coefficient for real band structure, any dimension (1D, 2D and 3D) at any Fermi energy and temperature. The simulation tool also incorporates various scattering mechanisms.
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