Showing 7 results for Gps
Volume 4, Issue 1 (9-2004)
Abstract
The error of inertial navigation systems increase versus time, therefore for achieving higher accuracy specially in long time navigations we have to use an aiding system. Global positioning system is the best aiding system in this case. In this paper we first simulate a GPS and INS; Then simulate tightly integration and finally review adaptation method of Kalman Filtering a Fuzzy adaptive Kalman filter is proposed in which adaptation is accomplished by adaptive tuning of covariance matrix of measurement noise (R) and process noise (Q). We have achieved adaptive tuning using Fuzzy systems and Covariance - Matching techniques .The results show that the adaptive fuzzy integration of GPS and INS would lead to better performance comparing to the usual methods of integration in which both R and Q matrices are constant.
Volume 5, Issue 0 (0-2005)
Abstract
Different methods exists for jamming mitigation and we should choose a method based an the jammer type and other parameters. One of the jammers is narrow band FM jammer and we use subspace projection techniques for the suppression of this type of jammer. In subspace projection technique, we estimate the IF of signals and construct the subspace vector that is orthogonal to jammer vector by increasing the number of antennas in the array; we enhance the performance of system. The subspace projection method was simulated in MATLAB and the receiver output SINR in several conditions was calculated.
In the case of IF estimation error, the SINR of the system is reduced; in this condition the use of an antenna array will increase the performance of the system compared to a single antenna.
Volume 5, Issue 3 (9-2016)
Abstract
Chilo partellus is a devastating sorghumand maize pest that exists worldwide. C. partellus gut proteases (CPGPs) were isolated, purified and characterized. We analyzed potential trypsin and chymotrypsin inhibitors (TIs) from tuber plants to identify the protease inhibitors (PIs) of CPGPs. PIs from Ipomoea batatas completely inhibited protease activity and growth and led to reduced C. partellus insect larvae weights. One PI was purified from I. batatas tubers and identified as a potent antagonist of CPGPs. In conclusion, we identified Ipomoea batatas inhibitors with significant potential applications in developing resistant transgenic sorghum and maize crops.
Volume 14, Issue 1 (3-2010)
Abstract
Boshehr is a coastal city located along the warm waters of persian gulf. It is limited to zagros mountains persian gulf, hableh river and Tangestan town from north, south, west and east, respectively. The study area is in between sea and land areas. Such especial situations make the formation of specific land forms in coastal regulation zone (CRZ). Howevre, land from studies, especially land forms in CRZ (land between low water line and 500 meters from high water line) are well sensed.
Therefore, such sensetive areas should be more considered and more efforts should be made to have better knowledge about them. This would enable a better planning and management of industrial, commercial, residential, environmetal and tourism problems of these areas. for better analysis and getting best knowledge for mapping land forms of this area, remote sensing, GIS and GPS technologies have been used. In this research, geology soils, climate and hydrology of the area were first studied. then, the charachteristics of the area, CRZ definition, land forms classificahion and their precise definition and also collection of tide statistics were made. First, remote sensing, preprocessing of the data was made and then, using digital and visual interpretation techniques, different land forms were identified.
regulation zone was drown. Based on ground truth data comparison, the final land from map within the CRZ was generated. the CRZ land from map showed thah the coatal areas of Boshehr are plagic in type and their formation is mainly due to land erosion factors than sea erosion. Also in this
area, the rules of crz are not observed and must be seriously considered.
Then, using extracted tidal and shore lines from satellite data, the coastal
Volume 14, Issue 6 (11-2012)
Abstract
Terfezia, Picoa and Tirmania, so called desert truffles, are mycorrhizal fungi mostly endemic to arid and semi-arid areas of the Mediterranean Region, where they are associated with Helianthemum and Carexspecies. The aim of this work was to study the identification, molecular analysis, distribution and hosts of these pezizalean hypogeous fungi in Iran. Among the specimens, Terfezia claveryi, Tirmania pinoyi, T. nivea, Picoa lefebvrei and P. juniperi were identified. Field, laboratory and anatomical studies showed that Helianthemum ledifolium, H. salicifolium, H. lippi and Carex stenophylum have ectomycorrhizal associations with five species in the studied areas. The results of molecular analysis showed that C. stenophylum roots form mycorrhizal associations with T. claveryi. Hyphal mantle was absent from sections of the mycorrhizas. The results of physico-chemical analyses on soil samples from different parts of the Fars Province in Iran showed that the genus Tirmania was more prevalent in soils with high CaCO3 and silt contents than the T. claveryi, P. lefebvrei and P. juniperi. The Canonical Correspondence Analysis (CCA) indicated that soil structure were an important environmental parameter influencing desert truffles distribution.
Mohammad Reza Mobasheri, Davod Ashourloo,
Volume 20, Issue 2 (4-2013)
Abstract
Total Perceptible Water (TPW) is an important parameter in climatology and weather forecasting and is directly related to any climate process. There are three approaches to estimate this parameter i.e. using radiosonde, using GPS and calculating from satellite images where the first two are localized and the last one can give an instant view of TPW in a vast region. The algorithm used for the TPW calculation from MODIS images is related to the ratio of the reflectance in a water vapor absorbing channel and the reflectance in a non-absorbing channel. Due to strong horizontal variation in the surface reflectance in non-absorbing channels, the retrieved TPW varies strongly from one pixel to its neighboring pixels while it is believed that the horizontal gradient of TPW is very weak. To solve this problem, a damping coefficient was added to the non-absorbing channel reflectance. It is found that this coefficient differs for different surface covers. The current work presents a procedure for calculating these coefficients. The results of a comparison between modified TPW and those extracted from GPS data showed a R2 of 0.81 whilst this was about 0.67 for non-modified MODIS TPW.
Volume 22, Issue 5 (12-2022)
Abstract
In smart cities, with using lots of new technologies, while creating appropriate facilities in routine urban life, infrastructure problems are investigated and the necessary measures are taken in a targeted and systematic manner to solve these problems. One of the most important technologies for managing infrastructure in smart cities is IT technology. GPS and smartphone sensors are other technologies that can be widely used in these cities. Streets, roads, and pavements are important infrastructures in any city and the future smart cities. Proper supervision, repair, and improvement of pavements, streets, and urban pathways are the main factor in reducing the cost of depreciation of vehicles and providing comfort and safety for citizens. On the other hand, if timely action is taken to restore and improve the pavement, huge costs of repair and reconstruction will be avoided, and this can significantly reduce the costs of urban management. The first step to achieving this goal is to identify the location of the roughness and distortion of the surface of the streets and urban pathways and the severity of these failures in the shortest possible time. In this paper, road surface roughnesses and failures have been studied using accelerometer sensors and GPS smartphone devices. Location and vertical acceleration data have been entered into GIS software and a quantitative index based on the values of vertical acceleration has been introduced to determine the quality of each section of urban road pavement. In this research, Androsensor software, which is a useful application for using smartphone sensors, has been used. This software is installed on two smartphones, Huawei, P30 Lite, and BlackBerry, Priv STV100. To collect the data, the smartphones were placed in a fixed position on the right and left sides of the car, on the dashboard. The collected data for analysis is transferred to the computer in Excel files. This research has been done in Kerman city and to collect data, different routes with specific failures have been selected. Data collection was performed in 81 pieces with a length of 500 meters and 24 pieces with a length of 200 meters (105 pieces, 45300 meters in total). By analyzing the vertical acceleration data and calculating some proposed indexes and comparing them, the best index has been selected. This index is classified into different ranges according to the field inspection of the pavement condition in the routes in this study, that each of which indicates the quality status of the pavement. Each of these intervals is introduced with a specific color, and by examining the index obtained in each route and the corresponding interval, the studied routes are marked with different colors on the map. Finally, it was found that the accelerometer sensors and GPS of smartphones can be used with low cost, high speed, and appropriate accuracy to check the surface of pavement of urban roads and grading the quality of the pavement. It also seems that in the smart cities of the future, which are based on IT technology, the use of user data, high accuracy in locating, and speed of action in prevention, the proposed method in this research can be used more favorably.
