Informatics Publishing Limited

Yang Liu ¹, Xian-Yong Meng ¹, Zhi-Hui Liu ², Dan-Lin Yu ³

Affiliations
1 School of Resources and Environment Science, Xinjiang University, Urumqi, 830046, CN
2 Key Laboratory of Oasis Ecology Ministry of Education, Xinjiang University, 830046, CN
3 Department of Earth & Environmental Studies, Montclair State University, Montclair, NJ, 07043, US

Abstract

Mountain flood that causes landslide and other geological disasters can damage the fragile ecological environment in mountain areas. In this paper, threshold and distribution model of accumulated temperature based on snowmelt flood magnitude are designed in mountainous watershed. Meanwhile, input data for this model make use of ample reliable data that include remote sensing and so on. In detail, this model simulates the average watershed temperature by using the meteorologic re-analysis data of the National Center for Atmospheric Research and calculates the average snow depth by using hyperspectral remote sensing data. In addition, the model related data comprise long-term observation experiments of the watershed, including the characteristics of accumulated snow and result of correlation between runoff and infiltration in runoff simulation experiment through distributed hydrological models (i.e., Soil and Water Assessment Tool and Distributed Hydrology Soil Vegetation Model). Finally, the average accumulated temperature of the watershed that causes snowmelt flood can be obtained through the aforementioned method, and the characteristics of the accumulated temperature distribution of the watershed area are determined based on the temperature lapse rate. The characteristics of accumulated temperature distribution can provide decision-making reference for monitoring the ecological environment in mountain areas and preventing and reducing disasters.

Keywords

Inverse Hydrological Problem, Flood Magnitude, Cropland Environment, Accumulated Temperature, Distribution, Accumulated Temperature, Threshold.

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Yanrong Guo ¹, Yanyun Han ¹, Baoguo Wu ¹, Yang Liu ²

Affiliations
1 School of Information Science and Technology, Beijing Forestry University, Beijing 100083, CN
2 Key Laboratory for Silviculture and Conservation of Ministry of Education, Beijing Forestry University, Beijing 100083, CN

Abstract

Differential site index models were constructed using both the algebraic difference approach (ADA) and the generalized algebraic difference approach (GADA) in this study to evaluate the site quality of forest land without the site index table. Data related to China fir (Cunninghamia lanceolata (Lamb.) Hook.) were selected to fit the differential site index models and then the optimal model was chosen. The optimal model was determined using an accuracy test and residual analysis, and then the dynamic update technique of the optimal model was studied by MATLAB and .NET. The results showed that Richards' differential site index model (SI = 19.171 × (H_t/19.171)^{ln(1-exp(-0.067×20))/ln(1-exp(-0.067 At)))} had the best prediction performance. The ADA and GADA could be used to evaluate site quality without the site index table and the differential site index model could provide prompt dynamic updates.

Keywords

Plantation Forests, Algebraic Difference Approach, Dynamic Update Technique, Richards’ Differential Site, Index Model.

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Yang Liu ¹, Yong Kong ¹, Guo Xu ¹

Affiliations
1 College of Electronic and Electrical Engineering, Shanghai University of Engineering Science, Long Teng Road 333#, Songjiang District, Shanghai-201620, CN

Abstract

Stereoscopic display technology in television, games, medical, education and other fields has more and more applications, different from the flat image only in the two-dimensional surface through the perspective, shadow and other effects to achieve three-dimensional, three-dimensional display can be from any angle of 360 degrees Watch the different sides of the image, is the real show of 3D. As the ideal three-dimensional display style, holographic three-dimensional technology is a combination of optoelectronic technology, computer graphics technology, sensing technology and display technology and other advanced high technology. In this paper, the advantages and disadvantages of various 3D display technologies are analyzed on the basis of the physiological and psychological mechanism of human eye-based three-dimensional object perception, and the principle and development of holographic three-dimensional display technology are analyzed emphatically and the future research direction is predicted.

Keywords

3D Display, Stereoscopic Display Technology, Depth Cue, Multi Sensor.

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