scholarly journals AN INVERSION APPROACH FOR BIOCHEMICAL PARAMETERS OF VEGETATION BASED ON THE PROSPECT-5 MODEL

2021 ◽  
Vol XLIII-B3-2021 ◽  
pp. 645-650
Author(s):  
X. Xing ◽  
X. Zheng ◽  
J. Liu
Keyword(s):  
Biochemical Parameters ◽  
Optimal Algorithm ◽  
Physical Models ◽  
Inversion Method ◽  
Equivalent Water Thickness ◽  
Dependent Variables ◽  
Parameters Analysis ◽  
The Common ◽  
Model Database ◽  
Optimizing Algorithm

Abstract. Accurate inversion of vegetation biochemicals using the PROSPECT model mostly depends on a proper inversion approach, including a suitable optimizing algorithm, appropriate dependent variables, and different properties from spectra of reflectance (R) and transmittance (T). In this paper, we propose a special inversion method using PROSPECT-5 and then explore its effectiveness in inverting chlorophyll, carotenoids, equivalent water thickness, and dry matter per area data from the ANGERS database. The inversion strategy includes (i) an optimal algorithm with constrained bounds (fminsearchbnd) to replace the common function fminsearch, (ii) and four parameters are considered together and separately as dependent variables of models, (iii) Using properties from the spectra of R, T and combined R&T to invert the above four biochemical parameters. The results show that fminsearchbnd can improve the model's R2 based on a field-measured database. Moreover, using the entire set of parameters together as the model inputs is more effective than using single parameters separately. T spectra are favoured for all parameter inversions in the model database while being inapplicable in the ANGERS database. These findings provide an appropriate inversion strategy for the PROSPECT-5 model in vegetation biochemical parameters analysis and suggest further research to develop an accurate inversion process for vegetation based on various physical models.

The Optimal Design on Connection Order of Network in Hydraulic Manifold Block

2011 ◽  
Vol 201-203 ◽  
pp. 2190-2194
Author(s):  
Jun Jun Zhang ◽  
Ji Sheng Wang ◽  
Jiang Yong Wang ◽  
Gang Liu ◽  
Jie Wang
Keyword(s):  
Genetic Algorithm ◽  
Optimal Design ◽  
Genetic Manipulation ◽  
Optimal Algorithm ◽  
Single Point ◽  
Adaptive Mutation ◽  
Gene Encoding ◽  
Mutation Strategy ◽  
The Common

As one of the important questions in the design of hydraulic manifold block — connection order of network, give a solution based on genetic algorithm. Genetic algorithm is the common effective intelligent optimal algorithm and suitable for solving a large combinatorial optimal problems. Gene encoding of ordinal representation, single-point crossover strategy and adaptive mutation strategy are used in the design of genetic manipulation.

WISE data and sparse photometry used for shape reconstruction of asteroids

2015 ◽  
Vol 10 (S318) ◽  
pp. 170-176 ◽  
Author(s):  
Josef Ďurech ◽  
Josef Hanuš ◽  
Victor M. Alí-Lagoa ◽  
Marco Delbo ◽  
Dagmara A. Oszkiewicz
Keyword(s):  
Rotation Period ◽  
Shape Reconstruction ◽  
Physical Models ◽  
Inversion Method ◽  
Wide Field ◽  
Reflected Light ◽  
Space Data ◽  
Spin Determination ◽  
Infrared Survey

AbstractAsteroid disk-integrated sparse-in-time photometry can be used for determination of shapes and spin states of asteroids by the lightcurve inversion method. To clearly distinguish the correct solution of the rotation period from other minima in the parameter space, data with good photometric accuracy are needed. We show that if the low-quality sparse photometry obtained from ground-based astrometric surveys is combined with data from the Wide-field Infrared Survey Explorer (WISE) satellite, the correct rotation period can be successfully derived. Although WISE observed in mid-IR wavelengths, we show that for the period and spin determination, these data can be modelled as reflected light. The absolute fluxes are not required since only relative variation of the flux over the rotation is sufficient to determine the period. We also discuss the potential of combining all WISE data with the Lowell photometric database to create physical models of thousands of asteroids.

The Division of Common Fractions

1960 ◽  
Vol 7 (3) ◽  
pp. 133-134
Author(s):  
Theodore S. Kolesnik
Keyword(s):  
Good Deal ◽  
Inversion Method ◽  
Common Denominator ◽  
Common Fractions ◽  
The Common ◽  
The One

There has been a Good Deal of discussion recently in regard to the best method of teaching the division of common fractions. Some teachers believe that the common denominator method is the one that should be taught. Others feel that the inversion method is best if it is preceded or followed by an explanation of why the inversion is mathematically sound. Another group feels that the inversion method should simply be “algorized” with any rationalization being delayed until such time that the pupil is mature enough to understand the complex fraction that is involved in the rationalization. Still another group favors the teaching of all methods with the pupil selecting the one that he particularly favors.

scholarly journals Asteroid models reconstructed from the Lowell Photometric Database and WISE data

2018 ◽  
Vol 617 ◽  
pp. A57 ◽  
Author(s):  
J. Ďurech ◽  
J. Hanuš ◽  
V. Alí-Lagoa
Keyword(s):  
Joint Inversion ◽  
Rotation Period ◽  
Thermal Infrared ◽  
Light Curves ◽  
Physical Models ◽  
Infrared Light ◽  
Inversion Method ◽  
Significant Discrepancy ◽  
Wide Range ◽  
New Models

Context. Information about the spin state of asteroids is important for our understanding of the dynamical processes affecting them. However, spin properties of asteroids are known for only a small fraction of the whole population. Aims. To enlarge the sample of asteroids with a known rotation state and basic shape properties, we combined sparse-in-time photometry from the Lowell Observatory Database with flux measurements from NASA’s WISE satellite. Methods. We applied the light curve inversion method to the combined data. The thermal infrared data from WISE were treated as reflected light because the shapes of thermal and visual light curves are similar enough for our purposes. While sparse data cover a wide range of geometries over many years, WISE data typically cover an interval of tens of hours, which is comparable to the typical rotation period of asteroids. The search for best-fitting models was done in the framework of the Asteroids@home distributed computing project. Results. By processing the data for almost 75 000 asteroids, we derived unique shape models for about 900 of them. Some of them were already available in the DAMIT database and served us as a consistency check of our approach. In total, we derived new models for 662 asteroids, which significantly increased the total number of asteroids for which their rotation state and shape are known. For another 789 asteroids, we were able to determine their sidereal rotation period and estimate the ecliptic latitude of the spin axis direction. We studied the distribution of spins in the asteroid population. Apart from updating the statistics for the dependence of the distribution on asteroid size, we revealed a significant discrepancy between the number of prograde and retrograde rotators for asteroids smaller than about 10 km. Conclusions. Combining optical photometry with thermal infrared light curves is an efficient approach to obtaining new physical models of asteroids. The amount of asteroid photometry is continuously growing and joint inversion of data from different surveys could lead to thousands of new models in the near future.

Probabilistic petrophysical-properties estimation integrating statistical rock physics with seismic inversion

Geophysics ◽  
2010 ◽  
Vol 75 (3) ◽  
pp. O21-O37 ◽  
Author(s):  
Dario Grana ◽  
Ernesto Della Rossa
Keyword(s):  
Seismic Data ◽  
Measurement Errors ◽  
Rock Physics ◽  
Seismic Inversion ◽  
Joint Estimation ◽  
Physical Models ◽  
Inversion Method ◽  
Petrophysical Properties ◽  
Reservoir Properties ◽  
Statistical Rock Physics

A joint estimation of petrophysical properties is proposed that combines statistical rock physics and Bayesian seismic inversion. Because elastic attributes are correlated with petrophysical variables (effective porosity, clay content, and water saturation) and this physical link is associated with uncertainties, the petrophysical-properties estimation from seismic data can be seen as a Bayesian inversion problem. The purpose of this work was to develop a strategy for estimating the probability distributions of petrophysical parameters and litho-fluid classes from seismics. Estimation of reservoir properties and the associated uncertainty was performed in three steps: linearized seismic inversion to estimate the probabilities of elastic parameters, probabilistic upscaling to include the scale-changes effect, and petrophysical inversion to estimate the probabilities of petrophysical variables andlitho-fluid classes. Rock-physics equations provide the linkbetween reservoir properties and velocities, and linearized seismic modeling connects velocities and density to seismic amplitude. A full Bayesian approach was adopted to propagate uncertainty from seismics to petrophysics in an integrated framework that takes into account different sources of uncertainty: heterogeneity of the real data, approximation of physical models, measurement errors, and scale changes. The method has been tested, as a feasibility step, on real well data and synthetic seismic data to show reliable propagation of the uncertainty through the three different steps and to compare two statistical approaches: parametric and nonparametric. Application to a real reservoir study (including data from two wells and partially stacked seismic volumes) has provided as a main result the probability densities of petrophysical properties and litho-fluid classes. It demonstrated the applicability of the proposed inversion method.

scholarly journals “Cultural additivity” and how the values and norms of Confucianism, Buddhism, and Taoism co-exist, interact, and influence Vietnamese society: a Bayesian analysis of long-standing folktales, R / Stan

2018 ◽  
Author(s):  
Quan-Hoang Vuong ◽  
Tung Ho ◽  
Viet-Phuong La ◽  
Dam Van Nhue ◽  
Bui Quang Khiem ◽  
...  
Keyword(s):  
Logistic Regression ◽  
Bayesian Analysis ◽  
Full Account ◽  
Empirical Results ◽  
Independent Variables ◽  
Religious Intolerance ◽  
Dependent Variables ◽  
Values And Beliefs ◽  
The Common ◽  
Bayesian Logistic Regression

Every year, the Vietnamese people reportedly burned about 50,000 tons of joss papers, which took the form of not only bank notes, but iPhones, cars, clothes, even housekeepers, in hope of pleasing the dead. The practice was mistakenly attributed to traditional Buddhist teachings but originated in fact from China, which most Vietnamese were not aware of. In other aspects of life, there were many similar examples of Vietnamese so ready and comfortable with adding new norms, values, and beliefs, even contradictory ones, to their culture. This phenomenon, dubbed “cultural additivity”, prompted us to study the co-existence, interaction, and influences among core values and norms of the Three Teachings –Confucianism, Buddhism, and Taoism–as shown through Vietnamese folktales. By applying Bayesian logistic regression, we evaluated the possibility of whether the key message of a story was dominated by a religion (dependent variables), as affected by the appearance of values and anti-values pertaining to the Three Teachings in the story (independent variables). Our main findings included the existence of the cultural additivity of Confucian and Taoist values. More specifically, empirical results showed that the interaction or addition of the values of Taoism and Confucianism in folktales together helped predict whether the key message of a story was about Confucianism, β_{VT⋅VC} =0.86. Meanwhile, there was no such statistical tendency for Buddhism. The results lead to a number of important implications. First, this showed the dominance of Confucianism because the fact that Confucian and Taoist values appeared together in a story led to the story’s key message dominated by Confucianism. Thus, it presented the evidence of Confucian dominance and against liberal interpretations of the concept of the Common Roots of Three Religions (“tam giáo đồng nguyên”) as religious unification or unicity. Second, the concept of “cultural additivity” could help explain many interesting socio-cultural phenomena, namely the absence of religious intolerance and extremism in the Vietnamese society, outrageous cases of sophistry in education, the low productivity in creative endeavors like science and technology, the misleading branding strategy in business. We are aware that our results are only preliminary and more studies, both theoretical and empirical, must be carried out to give a full account of the explanatory reach of “cultural additivity”.

scholarly journals Improving the Selection of Vegetation Index Characteristic Wavelengths by Using the PROSPECT Model for Leaf Water Content Estimation

2021 ◽  
Vol 13 (4) ◽  
pp. 821
Author(s):  
Jian Yang ◽  
Yangyang Zhang ◽  
Lin Du ◽  
Xiuguo Liu ◽  
Shuo Shi ◽  
...  
Keyword(s):  
Water Content ◽  
Biochemical Parameters ◽  
Leaf Water ◽  
Leaf Structure ◽  
Carotenoid Content ◽  
Leaf Water Content ◽  
Dry Matter Content ◽  
Structure Parameter ◽  
Equivalent Water Thickness ◽  
Selection Of

Equivalent water thickness (EWT) is a major indicator for indirect monitoring of leaf water content in remote sensing. Many vegetation indices (VIs) have been proposed to estimate EWT based on passive or active reflectance spectra. However, the selection of the characteristics wavelengths of VIs is mainly based on statistical analysis for specific vegetation species. In this study, a characteristic wavelength selection algorithm based on the PROSPECT-5 model was proposed to obtain characteristic wavelengths of leaf biochemical parameters (leaf structure parameter (N), chlorophyll a + b content (Cab), carotenoid content (Car), EWT, and dry matter content (LMA)). The effect of combined characteristic wavelengths of EWT and different biochemical parameters on the accuracy of EWT estimation is discussed. Results demonstrate that the characteristic wavelengths of leaf structure parameter N exhibited the greatest influence on EWT estimation. Then, two optimal characteristics wavelengths (1089 and 1398 nm) are selected to build a new ratio VI (nRVI = R1089/R1398) for EWT estimation. Subsequently, the performance of the built nRVI and four optimal published VIs for EWT estimation are discussed by using two simulation datasets and three in situ datasets. Results demonstrated that the built nRVI exhibited better performance (R2 = 0.9284, 0.8938, 0.7766, and RMSE = 0.0013 cm, 0.0022 cm, 0.0030 cm for ANGERS, Leaf Optical Properties Experiment (LOPEX), and JR datasets, respectively.) than that the published VIs for EWT estimation. It is demonstrated that the built nRVI based on the characteristic wavelengths selected using the physical model exhibits desirable universality and stability in EWT estimation.

scholarly journals Vliyanie narusheniya kostnogo metabolizma na sostoyanie tkaney parodonta u muzhchin reproduktivnogo vozrasta s sakharnym diabetom 1 tina i puti korrektsii

2006 ◽  
Vol 9 (3) ◽  
pp. 14-22
Author(s):  
K R Grigoryan ◽  
O R Grigoryan ◽  
T V Nikonova ◽  
V A Gorelysheva ◽  
G M BARER
Keyword(s):  
Diabetes Mellitus ◽  
Bone Metabolism ◽  
Biochemical Parameters ◽  
Optimal Algorithm ◽  
Diabetes Mellitus Type 1 ◽  
Diabetes Mellitus Type ◽  
Control Group ◽  
Childbearing Age ◽  
Second Stage

The aims of this study were to investigate the influence of alterations in bone metabolism and in hormonal and biochemical parameters on periodontium tissue as well as to estimate the optimal algorithm of investigation and treatment in men with diabetes mellitus type 1. During the first stage (12 months) the comparative analysis of conditions of pariodontium tissue was conducted in 60 men of childbearing age with diabetes mellitus type 1 and in 25 men of the control group. During the second stage (12 months) the markers of bone metabolism and the conditions of paradontium tissue were studied in 26 men of childbearing age with diabetes mellitus type 1 and in 25 men of the control group. The marker of bone resorption (CTX) was significantly lower (372,7 pkg/ml versus 473,0 pkg/ml; p= 0,006) and the marker of bone formation (OK) was significantly higher (27,6 ng/ml compared to 21,42 ng/ml; p< 0,005) in the group of patients who received ALPHA D3-TEVA (alfacalcidol 0,75mkg/day) and 2 tab CALCEMIN ADVANCE (calcium 1000 mg, cholecalciferol 400 UI) in comparison with the control group. Conclusion: the treatment with Calcium and Vitamin D is effective for prevention of bone resorbtion, particularly in jaws.

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