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111.
An ActiveX GPS control is presented which can be used to develop software applications with GPS functionality. It translates
the NMEA 0183 interface GPS instructions and triggers event procedures which are used by applications to access the GPS data.
It provides position data in the form of geographic coordinates as well as Universal Transverse Mercator (UTM) projected coordinates.
This control is recommended for the development of general purpose GPS-enabled applications which do not require a high level
of accuracy. A Visual Basic project is also included to demonstrate the use of various features of this control. Finally,
some real-time software applications are discussed which have been developed using this control. These applications include
static point averaging; path tracking; and imagery-based position mapping. 相似文献
112.
Arshad Amin Shahab Fazal Ahmad Mujtaba Sudhir Kumar Singh 《Journal of the Indian Society of Remote Sensing》2014,42(1):119-128
The present study focuses on the growing human needs which drive the native boatmen of the Kashmir valley (Hanjis) that bring the interchanges of land use/cover classes in Dal lake and its environs of Srinagar city. Further to assesses the effects of land transformation on lake water quality. The results suggested that the significant land use changes have been occurred during the past of 30 years (1981–2011). Besides this, interchange of land has taken place between different land uses classes, which has resulted into lake water pollution due the addition of various nutrients/pollutant discharged from Hanjis activities. The study concludes that the land transformation has converted the once fresh water lake much deteriorated pond. 相似文献
113.
AbstractThe Shahr-e-Babak region located in the Kerman metallogenic belt is one of the high potential segments of Urumieh–Dokhtar magmatic arc for porphyry copper and epithermal gold mineralization in the south of Iran. This high potential zone encompasses several porphyry copper deposits under exploitation, development and exploration stages. The aim of this study is to evaluate Landsat-8 data and comparison with the Advanced Spaceborne Thermal Emission and Reflection Radiometer data-sets for mapping hydrothermal alteration zones related to Cenozoic magmatic intrusions in Shahr-e-Babak region. Previous studies have proven the robust application of ASTER in lithological mapping and mineral exploration; nonetheless, the Landsat-8 data have high capability to map and detect hydrothermal alteration zones associated with porphyry copper and epithermal gold mineralization. In this investigation, several band combinations and multiplications, developed selective principal component analysis and image transformations were developed for discriminating hydrothermal alteration zones associated with porphyry copper mineralization using Landsat-8 data. 相似文献
114.
AbstractGeological mapping is one of the primary tasks of remote sensing. Remote sensing applications are especially useful when extreme environmental conditions inhibit direct survey such as in Antarctica. In this investigation, a satellite-based remote sensing approach was used for mapping alteration mineral zones and lithological units using Advanced Spaceborne Thermal Emission and Reflection Radiometer (ASTER) data in the Oscar II coast area, north-eastern Graham Land, Antarctic Peninsula. Specialized band ratios and band combinations were developed using visible and near infrared, shortwave infrared (SWIR) and thermal infrared spectral bands of ASTER for detecting alteration mineral assemblages and lithological units in Antarctic environments. Constrained Energy Minimization, Orthogonal Subspace Projection and Adaptive Coherence Estimator algorithms were tested to ASTER SWIR bands for detecting sub-pixels’ abundance of spectral features related to muscovite, kaolinite, illite, montmorillonite, epidote, chlorite and biotite. Results indicate valuable applicability of ASTER data for Antarctic geological mapping. 相似文献
115.
The authors would like to thank the discusser for his considerations and comments. The discusser believes that some of the derived formulations need to be referred to his previously published works and also some related studies have not been cited. 相似文献
116.
We investigate the time dynamics of monthly rainfall series intermittently recorded on seven climatic stations in northern Lebanon from 1939 to 2010 using the detrending fluctuation analysis (DFA) and the Fisher-Shannon (FS) method. The DFA is employed to study the scaling properties of the series, while the FS method to analyze their order/organization structure. The obtained results indicate that most all the stations show a significant persistent behavior, suggesting that the dynamics of the rainfall series is governed by positive feedback mechanisms. Furthermore, we found that the Fisher Information Measure (the Shannon entropy power) seems to decrease (increase) with the height of the rain gauge; this indicates that the rainfall series appear less organized and less regular for higher-located stations. Such findings could be useful for a better comprehension of the climatic regimes governing northern Lebanon. 相似文献
117.
It is shown that a strongly magnetized isothermal pair plasma near the surface of a pulsar supports low-frequency (in comparison
to electron cyclotron frequency) toroidal electrostatic plasma modes in the equatorial region. Physically, the thermal pressure
coupled with the magnetic pressure creates the low frequency oscillations which may grow for particular case of inhomogeneities
of the equilibrium magnetic field and the pair plasma density. 相似文献
118.
119.
Adaptive multi‐rate interface: development and experimental verification for real‐time hybrid simulation
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Amin Maghareh Jacob P. Waldbjørn Shirley J. Dyke Arun Prakash Ali I. Ozdagli 《地震工程与结构动力学》2016,45(9):1411-1425
Real‐time hybrid simulation (RTHS) is a powerful cyber‐physical technique that is a relatively cost‐effective method to perform global/local system evaluation of structural systems. A major factor that determines the ability of an RTHS to represent true system‐level behavior is the fidelity of the numerical substructure. While the use of higher‐order models increases fidelity of the simulation, it also increases the demand for computational resources. Because RTHS is executed at real‐time, in a conventional RTHS configuration, this increase in computational resources may limit the achievable sampling frequencies and/or introduce delays that can degrade its stability and performance. In this study, the Adaptive Multi‐rate Interface rate‐transitioning and compensation technique is developed to enable the use of more complex numerical models. Such a multi‐rate RTHS is strictly executed at real‐time, although it employs different time steps in the numerical and the physical substructures while including rate‐transitioning to link the components appropriately. Typically, a higher‐order numerical substructure model is solved at larger time intervals, and is coupled with a physical substructure that is driven at smaller time intervals for actuator control purposes. Through a series of simulations, the performance of the AMRI and several existing approaches for multi‐rate RTHS is compared. It is noted that compared with existing methods, AMRI leads to a smaller error, especially at higher ratios of sampling frequency between the numerical and physical substructures and for input signals with high‐frequency content. Further, it does not induce signal chattering at the coupling frequency. The effectiveness of AMRI is also verified experimentally. Copyright © 2016 John Wiley & Sons, Ltd. 相似文献
120.
The concentrations of Cd, Cu, Pb, Zn, Ni and Fe were determined in the surface sediment and marine gastropod Nerita lineata collected in May 2005 from the intertidal zone of Dumai, Sumatera, Indonesia and Johor, Peninsular Malaysia. The results showed that metal concentrations in sediment and the soft tissue of N. lineata varied at different sampling stations. Mean heavy metal concentrations were 0. 92 μg/g(Cd) ;6.40 μg/g(Cu) ;32.77 μg/g(Pb) ;54.41μg/g(Zn) ;11.56 μg/g(Ni) and 2.97%(Fe) in sediment from Dumai and 1.15 μg(Cd) ;26.73 μg/g(Cu) ;53.45μg/g(Pb) ;130.77 μg/g(Zn) ;20.79 μg/g( Ni ) and 2.72% (Fe) in sediment from Johor. Concentrations of metals in gastropod N. lineata were 0.71 μg/g(Cd) ;15.16 μg(Cu) ;9.35 μg/g(Pb) ;94.69 μg/g(Zn) ;5.08 μg/g(Ni) and 397.97 μg/g(Fe) in samples from Dumai and 1.24 μg(Cd) ;18.02 μg/g(Cu) ;19.75 μg/g(Pb) ;95.09 μg/g(Zn) ;5.57 μg/g ( Ni ) and 473. 56 μg/g (Fe) in samples from Johor. Although they were not statistically significant (p >0.05), heavy metal concentrations in N. lineata were correlated with the concentrations of respective metals in sediment in both samples from Dumai and Johor. In general, samples of sediment and gastropod from Johor accumulated significantly higher heavy metal concentrations when compared to samples from Dumai(p < 0. 05). Higher concentrations of metals were recorded in samples collected from the stations close to the industrial and anthropogenic activities in both Dumai and Johor areas. However, most of the concentrations were still comparable to the previous reported studies from other geographical areas. 相似文献