The Infona portal uses cookies, i.e. strings of text saved by a browser on the user's device. The portal can access those files and use them to remember the user's data, such as their chosen settings (screen view, interface language, etc.), or their login data. By using the Infona portal the user accepts automatic saving and using this information for portal operation purposes. More information on the subject can be found in the Privacy Policy and Terms of Service. By closing this window the user confirms that they have read the information on cookie usage, and they accept the privacy policy and the way cookies are used by the portal. You can change the cookie settings in your browser.
Pedestrian position tracking is essential in implementing many of the new location based services in cellular networks. The ability for positioning in non-line of sight (NLOS) environments has made cellular network based positioning highly popular. However, the position estimation fine-tuning step in the current cellular network based positioning algorithm is not utilizing the available information...
Baseline in signals is a relatively complicated problem in analysis of signals obtained in various analytical techniques such as chromatography and spectroscopy. In this article there are presented results of tests on four algorithms for a baseline estimation in chromatographic signals. Two of them are based on a polynomial fitting in a region of detected peaks. Another two algorithms, i.e. assymetric...
A switched-compensation technique (SCT) is proposed for switched-capacitor circuit applications to provide fast settling performance while reducing the quiescent power consumption. The SCT can be easily implemented into flip-around switched-capacitor amplifier in which the settling time requirement is a critical index of performance. Simulation results based on a 0.13µm CMOS process are presented...
We considered the new quasi-likelihood amplitude estimate algorithm for the ultra wide band quasi radio signal with unknown initial phase and inaccurately known duration against white Gaussian noise. Its block diagram was presented in single-channel units. We found the statistical characteristics of the introduced estimate and we also investigated the influence of the prior signal duration ignorance...
The author has introduced a generic method for photogrammetric survey using a multi-rotor unmanned aerial vehicle (UAV) for mapping a simulated model and slope area. The objective of this study is to assess the capabilities of UAV for slope mapping. This study only concentrates on multi-rotor UAV, which is known as Hexacopter. Several ground control points (GCP) and checked point (CP) were established...
In many practical situations, we make predictions based on the measured and/or estimated values of different physical quantities. The accuracy of these predictions depends on the accuracy of the corresponding measurements and expert estimates. Often, for each quantity, there are several different sources of inaccuracy. Usually, to estimate the prediction accuracy, we first combine, for each input,...
Micro aerial vehicle (MAV) can be used as an efficient image acquiring tool. However, aerial video sequence has a large amount of redundant information, which will delay the scene reconstruction process and decrease the structure accuracy. Meanwhile conventional frame decimation approaches normally have time-consuming feature matching step. This paper proposes a hierarchical frame decimation approach...
Limited by the MEMS sensor's sampling rate, the non-commutable error that derived from finite rotation of rigid body should not be neglected. Aimed at high dynamic motion and high-speed rotation, this paper presents an optimized algorithm based on expert control system (ECS) which combined rotation vector algorithm and quaternion to solve attitude estimation. Compared with the traditional quaternion...
Recovering 3D depth from a single outdoor image is a basic problem in Computer Vision and Close-Range Photogrammetry. In this paper, an efficient depth estimation approach from a single outdoor image is presented. According to scene classification, depth of regions marked as sky, ground and vertical labels is respectively predicated. Firstly, a more accurate depth calculation model for ground regions...
A heuristic utilizing both spectral and spatial information is proposed for active learning. It addresses the issue of iteratively querying most informative training samples with a special focus on spatial-contextual image classification. With the aim to utilize all information during the learning process, the proposed heuristic queries unlabeled pixels considering spectral-spatial inconsistency (SSI),...
Non-randomness within canopies and woody component are two factors limiting the accuracy of indirect leaf area index (LAI) measurement. Here we combine the path length distribution model and Multispectral Canopy Imager (MCI) together for the first time to improve the accuracy. The results show that non-randomness within canopies underestimates 17.1%-28.2% LAI, while woody component overestimates 14...
This paper proposes a novel method for land cover area frame stratification based on corn planting frequency and percent cultivation. South Dakota U.S. geospatial crop frequency (2008–2013) and cultivation (2013) data layers created from NASS Cropland Data Layers are utilized to develop a novel area sampling frame (ASF) stratification design. Eight corn planting frequency strata are derived using...
The precision of the mutilsquint methods effects by several factors. This paper deduces the effects of these factors on the multisquint estimation accuracy. Expression of the estimation accuracy is deduced, which provides theoretical bases for the parameter choice and system design of the airborne interferometric SAR.
Meteorological stations often have biased distributions in remote areas, and sample biases typically lead to biased estimation of areal precipitation. We introduce a method termed the Biased Sentinel Hospital based Area Disease Estimation (B-SHADE) to correct for the bias in the locations of meteorological observations and to obtain a best linear unbiased estimation of the mean areal precipitation...
This paper proposes a modified hybrid method that combines Received Signal Strength (RSS) and Direction of Arrival (DOA) estimation based on MUSIC (Multiple Signal Classification) using circular antenna array. Simulation results are carried out to verify the improved performance obtained using the proposed hybrid method. This takes the form of successful detection of coherent signals at a higher accuracy...
ALOS-2 satellite has been successfully launched by JAXA on May 24th 2014, it is equipped with an L-Band (PALSAR-2) fully polarimetric SAR. Many improvements have been made with respect to the former ALOS satellite: the exploitation of a dual receiving antenna allows to broaden the imaged swath whereas spotlight mode ensures a very high resolution on a specific location. The revisit time has been lowered...
This contribution presents two experiments performed with the TerraSAR-X (TSX) and TanDEM-X (TDX) satellites working in the pursuit monostatic configuration. Their objective is to estimate the along-track component of the motion in the scene in repeat-pass scenarios with an accuracy better than the one given by the stripmap azimuth resolution. Such performance is possible by exploiting the angular...
In this study we demonstrate a method for estimating the photosynthetically active radiation (PAR) transmittance of individual trees in an urban district. The leaf area density (LAD) distribution, derived from airborne light detection and ranging (LiDAR) data using a method proposed by our previous study, is applied to radiative transfer simulation of vegetation. Estimation accuracy of the PAR transmittance...
The results of a two-year precision agriculture project have clearly demonstrated that TanDEM-X can successfully classify crops morphology through cultivation period. It has been found that TanDEM-X mission is capable of tracking the crop height, and the accuracy of the height estimation depends on the crop morphology, which causes a diversity between canopy top and acquisition phase center. In this...
Crop growth stages are important factors for segmenting the crop growing seasons and analyzing their growth conditions against normal conditions by periods. Time series of high temporal resolution, up to daily, satellite remotely sensed data are used in establishing crop growth estimation model and estimate the growth stages. The daily surface reflectance data from Moderate Resolution Imaging Spectroradiometer...
Set the date range to filter the displayed results. You can set a starting date, ending date or both. You can enter the dates manually or choose them from the calendar.