Tracking technology for optoelectronic imaging platform of tethered balloon based on DGPS/INS

2011 ◽  
Vol 19 (2) ◽  
Author(s):  
Y. Wang ◽  
Z. Wang ◽  
W. Zhou ◽  
X. Han
Keyword(s):  
Attitude Change ◽  
Elevation Angle ◽  
Field Of View ◽  
Line Of Sight ◽  
Theoretical Point ◽  
Tethered Balloon ◽  
Location Data ◽  
Initial Location ◽  
Ground Target ◽  
The Difference

AbstractIn this paper, a tracking method for optoelectronic imaging platform of tethered balloon based on difference global positioning system/inertial navigation system is presented in detail. The location and attitude information of optoelectronic imaging platform, the azimuth and elevation angles of camera’s line of sight are used by this method to locate the ground target at the centre point of the camera’s field of view through corresponding coordinate transformation. And then, the method makes use of the update position and attitude information to solve the theoretical point of camera’s line of sight inversely. Finally, an angle control commend will be sent to the inertially-stabilized turntable on the optoelectronic imaging platform, which will adjust its azimuth and elevation angle to make the camera’s line of sight to the ground target. A lot of experiments are conducted, and the results show that the initial ground target is always in the centre of camera’s field of view no matter how the balloon’s position and attitude change, and the new location data of ground target has little difference with the initial location data, while the difference between them is close to 0.

3-D Electronic Maps, Design Implications for the Effects of Elevation Angle Disparity, Complexity, and Feature Type

1997 ◽  
Vol 41 (1) ◽  
pp. 23-27 ◽  
Author(s):  
Joseph C. Hickox ◽  
Christopher D. Wickens
Keyword(s):  
Elevation Angle ◽  
Three Dimensional ◽  
Field Of View ◽  
Viewing Angle ◽  
Large Screen ◽  
The Difference ◽  
Main Effects

Three-dimensional navigational displays have received a fair amount of attention in the literature lately. In this study, we utilized a navigational checking task and manipulated elevation angle disparity, complexity and feature type (defined by man-made vs. natural) and measured its effects on latency and accuracy. Elevation angle disparity was measured in terms of the difference between the sin of the viewing angle or Forward Field of View (FFOV) and the sin of the map angle. A same/different paradigm was employed as subjects compared navigational scenes presented on both a CRT (simulating the map) and projected on a large screen (simulating the FFOV). Main effects were found with the elevation angle disparity, complexity and feature type. Significant interactions were found with elevation angle disparity and feature type, and complexity and feature type. Conclusions are made based upon these findings and their implications for the design of 3-D electronic maps.

scholarly journals Characterization of MIPAS elevation pointing

2007 ◽  
Vol 7 (6) ◽  
pp. 1615-1628 ◽  
Author(s):  
M. Kiefer ◽  
T. von Clarmann ◽  
U. Grabowski ◽  
M. De Laurentis ◽  
R. Mantovani ◽  
...  
Keyword(s):  
Systematic Difference ◽  
Field Of View ◽  
Line Of Sight ◽  
Viewing Angle ◽  
Temporal Behaviour ◽  
Expected Time ◽  
Satellite Attitude ◽  
The Difference ◽  
Level 2

Abstract. Sufficient knowledge of the pointing is essential for analyses of limb emission measurements. The scientific retrieval processor for MIPAS on ENVISAT operated at IMK allows the retrieval of pointing information in terms of tangent altitudes along with temperature. The retrieved tangent altitudes are independent of systematic offsets in the engineering Line-Of-Sight (LOS) information delivered with the ESA Level 1b product. The difference of pointing retrieved from the reprocessed high resolution MIPAS spectra and the engineering pointing information was examined with respect to spatial/temporal behaviour. Among others the following characteristics of MIPAS pointing could be identified: Generally the engineering tangent altitudes are too high by 0–1.8 km with conspicuous variations in this range over time. Prior to December of 2003 there was a drift of about 50–100 m/h, which was due to a slow change in the satellite attitude. A correction of this attitude is done twice a day, which leads to discontinuities in the order of 1–1.5 km in the tangent altitudes. Occasionally discontinuities up to 2.5 km are found, as already reported from MIPAS and SCIAMACHY observations. After an update of the orbit position software in December 2003 values of drift and jumps are much reduced. There is a systematic difference in the mispointing between the poles which amounts to 1.5–2 km, i.e. there is a conspicuous orbit-periodic feature. The analysis of the correlation between the instrument's viewing angle azimuth and differential mispointing supports the hypotheses that a major part of this latter phenomenon can be attributed to an error in the roll angle of the satellite/instrument system of approximately 42 mdeg. One conclusion is that ESA level 2 data should be compared to other data exclusively on tangent pressure levels. Complementary to IMK data, ESA operational LOS calibration results were used to characterize MIPAS pointing. For this purpose MIPAS is used as a radiometer while the passage of infrared bright stars through the instrument's field of view is recorded. Deviation from expected time of passage gives information about mispointing. Results are: a pronounced seasonal variation of the LOS is seen before a correction of on-board software took place in December of 2003. Further a pitch bias of 26 mdeg with respect to the platform attitude information is found, which corresponds to 1.45 km tangent altitude offset towards low altitudes.

scholarly journals Characterization of MIPAS elevation pointing

2006 ◽  
Vol 6 (6) ◽  
pp. 13075-13110 ◽  
Author(s):  
M. Kiefer ◽  
T. von Clarmann ◽  
U. Grabowski ◽  
M. De Laurentis ◽  
R. Mantovani ◽  
...  
Keyword(s):  
Major Part ◽  
Systematic Difference ◽  
Field Of View ◽  
Line Of Sight ◽  
Viewing Angle ◽  
Temporal Behaviour ◽  
Expected Time ◽  
Satellite Attitude ◽  
The Difference

Abstract. Sufficient knowledge of the pointing is essential for analyses of limb emission measurements. The scientific retrieval processor for MIPAS operated at IMK allows to retrieve pointing information in terms of tangent altitudes along with temperature. The retrieved tangent altitudes are independent of the engineering Line-Of-Sight (LOS) information delivered with the ESA Level 1b product. The difference of pointing retrieved from the reprocessed high resolution MIPAS spectra and the engineering pointing information was examined with respect to spatial/temporal behaviour. Among others the following characteristics of MIPAS pointing could be identified: Generally the engineering tangent altitudes are too high by 0–1.8 km with conspicuous variations in this range over time. Prior to December of 2003 there was a drift of about 50–100 m/h, which was due to a slow change in the satellite attitude. A correction of this attitude is done twice a day, which led to discontinuities in the order of up to 2 km in the tangent altitudes. There is a systematic difference in the mispointing between the poles which amounts to 1.5–2 km, i.e. there is a conspicuous orbit-periodic feature. The analysis of the correlation between the instrument's viewing angle azimuth and differential mispointing supports the hypotheses that a major part of this latter phenomenon can be attributed to an uncorrected roll angle of the satellite/instrument system of approximately 54 mdeg. Complementary to this, ESA operational LOS calibration results were used to characterize MIPAS pointing. For this purpose MIPAS is used as a radiometer while the passage of infrared bright stars through the instrument's field of view is recorded. Deviation from expected time of passage gives information about mispointing. A pronounced seasonal variation of the LOS is seen before a correction of on-board software took place in December of 2003. Further a pitch bias of 24 mdeg with respect to the platform attitude information is found.

Structuring, Motions and Shapes of Corona Emission Line Profiles

1994 ◽  
Vol 144 ◽  
pp. 421-426
Author(s):  
N. F. Tyagun
Keyword(s):  
Emission Line ◽  
Filling Factor ◽  
Direct Relationship ◽  
Coronal Plasma ◽  
Line Of Sight ◽  
Line Profiles ◽  
The Difference ◽  
Yellow Line ◽  
Red Line

AbstractThe interrelationship of half-widths and intensities for the red, green and yellow lines is considered. This is a direct relationship for the green and yellow line and an inverse one for the red line. The difference in the relationships of half-widths and intensities for different lines appears to be due to substantially dissimilar structuring and to a set of line-of-sight motions in ”hot“ and ”cold“ corona regions.When diagnosing the coronal plasma, one cannot neglect the filling factor - each line has such a factor of its own.

Retail Mix Dan Kepuasan Konsumen Minimarket

Liquidity ◽  
2018 ◽  
Vol 7 (1) ◽  
pp. 53-62
Author(s):  
Siti Maryama ◽  
Yayat Sujatna
Keyword(s):  
Consumer Satisfaction ◽  
Quantitative Method ◽  
Descriptive Analysis ◽  
T Test ◽  
Primary Data ◽  
Retail Industry ◽  
Location Data ◽  
Store Design ◽  
Customer Services ◽  
The Difference

The purpose of this study is to (1) analyzing the level of retail mix consumer satisfaction; (2) analyze the dominant variable in retail mix consumer satisfaction; (3) analyze the difference of retail mix consumer satisfaction performed. The observed of the retail industry is Alfamidi and Indomaret. The study was designed into a descriptive-quantitative method. The source of primary data obtained from the questionnaire of 100 respondents. The formulating variable of retail mix includes: merchandise assortments, pricing, customer services Store design and display, communication mix, and location. Data analyze by using descriptive, analysis of factors, and t-test. The result confirmed that the level of retail mix consumer satisfaction in both industry is relatively similar. However, it can be stated that the respondents were more satisfied to Indomaret compared with Alfamart.

scholarly journals Long-Term Observations of Microwave Brightness Temperatures over a Metropolitan Area: Comparison of Radiometric Data and Spectra Simulated with the Use of Radiosonde Measurements

2021 ◽  
Vol 13 (11) ◽  
pp. 2061
Author(s):  
Mikhail V. Belikovich ◽  
Mikhail Yu. Kulikov ◽  
Dmitry S. Makarov ◽  
Natalya K. Skalyga ◽  
Vitaly G. Ryskin ◽  
...  
Keyword(s):  
Radiative Transfer ◽  
Elevation Angle ◽  
Radiative Transfer Model ◽  
Transfer Model ◽  
Systematic Bias ◽  
Tropospheric Temperature ◽  
Absorption Model ◽  
60 Ghz ◽  
Error Budget ◽  
The Difference

Ground-based microwave radiometers are increasingly used in operational meteorology and nowcasting. These instruments continuously measure the spectra of downwelling atmospheric radiation in the range 20–60 GHz used for the retrieval of tropospheric temperature and water vapor profiles. Spectroscopic uncertainty is an important part of the retrieval error budget, as it leads to systematic bias. In this study, we analyze the difference between observed and simulated microwave spectra obtained from more than four years of microwave and radiosonde observations over Nizhny Novgorod (56.2° N, 44° E). We focus on zenith-measured and elevation-scanning data in clear-sky conditions. The simulated spectra are calculated by a radiative transfer model with the use of radiosonde profiles and different absorption models, corresponding to the latest spectroscopy research. In the case of zenith-measurements, we found a systematic bias (up to ~2 K) of simulated spectra at 51–54 GHz. The sign of bias depends on the absorption model. A thorough investigation of the error budget points to a spectroscopic nature of the observed differences. The dependence of the results on the elevation angle and absorption model can be explained by the basic properties of radiative transfer and by cloud contamination at elevation angles.

scholarly journals Measurements of the 3.3 μm Diffuse Galactic Emission Feature with AROME

1990 ◽  
Vol 139 ◽  
pp. 212-213
Author(s):  
M. Giard ◽  
F. Pajot ◽  
J. M. Lamarre ◽  
G. Serra
Keyword(s):  
Surface Brightness ◽  
Galactic Plane ◽  
Elevation Angle ◽  
Emission Feature ◽  
Field Of View ◽  
Interstellar Matter ◽  
Galactic Emission ◽  
Polycyclic Aromatic ◽  
Hydrocarbon Molecules ◽  
Ir Emission

AROME∗ is a balloon-borne experiment which was built to carry out measurements of IR emission features in the diffuse galactic flux. The field of view is 0.5° and surface brightness gradients are detected through azimuthal scanning at a constant elevation angle. The detection of a feature is done by comparison of the fluxes measured in narrow and wide photometric bands centered on the feature's wavelength. Two flights have been performed (August 1987, October 1988), which detected a 3.3 μm feature in the direction of the galactic plane −6° < b < 6°, 60° > l > −50°. Since this feature is characteristic of aromatic C-H bonds, we assigned it to the emission of transiently heated polycyclic aromatic hydrocarbon molecules (PAHs). With this assumption, AROME measurements show that PAHs are an ubiquitous component of the interstellar matter which contain about 10% of the available cosmic carbon.

Towards Finding the Optimum Position in the Visual Field for a Head Worn Display Used for Task Guidance with Non-registered Graphics

2021 ◽  
Vol 5 (1) ◽  
pp. 1-26
Author(s):  
Georgianna Lin ◽  
Malcolm Haynes ◽  
Sarthak Srinivas ◽  
Pramod Kotipalli ◽  
Thad Starner
Keyword(s):  
Visual Field ◽  
Order Picking ◽  
Field Of View ◽  
Line Of Sight ◽  
Single Task ◽  
Horizontal Field ◽  
Optimum Position ◽  
Preference Task ◽  
Task Efficiency ◽  
Task Guidance

Where should a HWD be placed in a user's visual field? We present two studies that compare comfort, preference, task efficiency and accuracy for various HWD positions. The first study offsets a 9.2° horizontal field-of-view (FOV) display temporally (toward the ear) from 0° to 30° in 10° steps. 30° proves too uncomfortable while 10° is the most preferred position for a simple button-pushing game, corroborating results from previous single-task reading experiments. The second experiment uses a Magic Leap One to compare 10° x 10° FOV interfaces centered at line-of-sight, temporally offset 15° (center-right), inferiorly offset 15° (bottom-center), and offset in both directions (bottom-right) for an order picking task. The bottom-right position proved worst in terms of accuracy and several subjective metrics when compared to the line-of-sight position.

Research on Physical MPPT of Photovoltaic Array System Based on Image Processing

2013 ◽  
Vol 321-324 ◽  
pp. 1138-1144
Author(s):  
Chao Liu ◽  
Jing Hui
Keyword(s):  
Image Processing ◽  
Tracking Error ◽  
Elevation Angle ◽  
Image Sensor ◽  
Azimuth Angle ◽  
Field Of View ◽  
The Sun ◽  
Photovoltaic Array ◽  
Point Tracking ◽  
Power Point

Based on analyzing the development and the performance feature of existing solar tracker, we propose a solar Maximum Power Point Tracking (MPPT) strategy which combines photoelectric sensor and image processing. Firstly, photoelectric tracking mode positions the sun in the field of view of the image sensor. Then, the position of the sun image is captured by the image sensor. After that, we can find the coordinates of the sun spot in the field of view through image binarization processing. According to the number of steps of stepper motor rotation which is calculated by the deviation of coordinates, the controller drives the biaxial photosensitive (PV) array tracking device, making the sun spot always fall in the centre of the image. Tests show that the elevation angle and azimuth angle of the tracking range of the photovoltaic array are both 0～270°.The average tracking error of elevation angle is less than 0.7°, and the average tracking error of azimuth angle is less than 0.5°.

scholarly journals Subtraction of Bright Point Sources from Synthesis Images of the Epoch of Reionization

2011 ◽  
Vol 28 (1) ◽  
pp. 46-57 ◽  
Author(s):  
B. Pindor ◽  
J. S. B. Wyithe ◽  
D. A. Mitchell ◽  
S. M. Ord ◽  
R. B. Wayth ◽  
...  
Keyword(s):  
Active Galactic Nuclei ◽  
Dynamic Range ◽  
Low Frequency ◽  
Neutral Hydrogen ◽  
Galactic Nuclei ◽  
Point Sources ◽  
Field Of View ◽  
Bright Point ◽  
Line Of Sight ◽  
Diffuse Background

AbstractBright point sources associated with extragalactic active galactic nuclei and radio galaxies are an important foreground for low-frequency radio experiments aimed at detecting the redshifted 21-cm emission from neutral hydrogen during the epoch of reionization. The frequency dependence of the synthesized beam implies that the sidelobes of these sources will move across the field of view as a function of observing frequency, hence frustrating line-of-sight foreground subtraction techniques. We describe a method for subtracting these point sources from dirty maps produced by an instrument such as the MWA. This technique combines matched filters with an iterative centroiding scheme to locate and characterize point sources in the presence of a diffuse background. Simulations show that this technique can improve the dynamic range of epoch-of-reionization maps by 2—3 orders of magnitude.

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