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Synthetic aperture radar (SAR) has been an unparalleled tool in cloudy and rainy regions as it allows observations throughout the year because of its all-weather, all-day operation capability. In this paper, the influence of Wenchuan Earthquake on the Sichuan Giant Panda habitats was evaluated for the first time using SAR interferometry and combining data from C-band Envisat ASAR and L-band ALOS PALSAR data. Coherence analysis based on the zero-point shifting indicated that the deforestation process was significant, particularly in habitats along the Min River approaching the epicenter after the natural disaster, and as interpreted by the vegetation deterioration from landslides, avalanches and debris flows. Experiments demonstrated that C-band Envisat ASAR data were sensitive to vegetation, resulting in an underestimation of deforestation; in contrast, L-band PALSAR data were capable of evaluating the deforestation process owing to a better penetration and the significant coherence gain on damaged forest areas. The percentage of damaged forest estimated by PALSAR decreased from 20.66% to 17.34% during 2009-2010, implying an approximate 3% recovery rate of forests in the earthquake impacted areas. This study proves that long-wavelength SAR interferometry is promising for rapid assessment of disaster-induced deforestation, particularly in regions where the optical acquisition is constrained. [ABSTRACT FROM AUTHOR]

Owing to the development of spaceborne synthetic aperture radar (SAR) platforms, and in particular the increase in the availability of multi-source (multi-band and multi-resolution) data, it is now feasible to design a surface displacement monitoring application using multi-temporal SAR interferometry (MT-InSAR). Landslides have high socio-economic impacts in many countries because of potential geo-hazards and heavy casualties. In this study, taking into account the merits of ALOS PALSAR (L-band, good coherence preservation) and TerraSAR (X-band, high resolution and short revisit times) data, we applied an improved small baseline InSAR (SB-InSAR) with 3-D phase unwrapping approach, to monitor slope superficial displacement in Hong Kong, China, a mountainous subtropical zone city influenced by over-urbanization and heavy monsoonal rains. Results revealed that the synergistic use of PALSAR and TerraSAR data produces different outcomes in relation to data reliability and spatial-temporal resolution, and hence could be of significant value for a comprehensive understanding and monitoring of unstable slopes. [ABSTRACT FROM AUTHOR]

In order to improve network throughput and reduce energy consumption, we propose in this paper a cross-layer optimization design that is able to achieve multicast utility maximization and energy consumption minimization. The joint optimization of congestion control and power allocation is formulated to be a nonlinear nonconvex problem. Using dual decomposition, a distributed optimization algorithm is proposed to avoid the congestion by control flow rate at the source node and eliminate the bottleneck by allocating the power at the intermediate node. Simulation results show that the cross-layer algorithm can increase network performance, reduce the energy consumption of wireless nodes and prolong the network lifetime, while keeping network throughput basically unchanged. [ABSTRACT FROM AUTHOR]

The Interferometric Point Target Analysis (IPTA) technique and Advanced Synthetic Aperture Radar (ASAR) images acquired over Hong Kong from 2007-2008 were used to detect ground deformation in the urban area of Guangzhou city in South China. A ground deformation rate map with scattered distribution of point targets shows the maximum subsidence (rise) rate as high as -26 to -20 mma-1 (16-21 mma-1), implying that the study area is an active zone for ground deformation. Based on the point target map, a contour ground deformation rate map is generated. The map shows three major subsidence zones located in the middle-west, the east, and the southwest of the study area, respectively. All the six ground collapse accidents that occurred in 2007-2008 fall within the subsidence zones, qualitatively validating the IPTA results. Ground subsidence and geological conditions on Datansha Island are examined. The results indicate that the local geological conditions, such as limestone Karst geomorphology as well as silt layers characterized by high water content, high void ratio, high compressibility, low bearing capacity and low shear strength, and underground engineering projects are responsible for ground subsidence and ground collapse accidents occurred there. [ABSTRACT FROM AUTHOR]

A compact microstrip diplexer for UMTS and WCDMA systems is presented. The size of the diplexer can be reduced by using capacitance loaded square meander loop resonators. Owing to the capacitance loaded arms, the resonator has the advantages of compact size and harmonic suppression. The two degenerate-mode resonances are used to form the lower and upper channel of the diplexer, respectively, which generate two transmission zeroes so as to obtain high frequency selectivity. Simulated and measured results are presented and show good agreement. [ABSTRACT FROM AUTHOR]

A novel compact dual-band bandpass filter (BPF) using a hybrid structure of microstrip patch and coplanar waveguide (CPW) is proposed, designed, and implemented. The dual-band response can be realised by embedding two CPW structures in the microstrip square patch, which can not only disturb two fundamental degenerated modes, TM100 and TM010, but also adjust the resonant frequency of the TM110 mode. The two degenerated modes are used to form the first passband while the TM110 mode and two CPW resonators are used to generate the second passband. The first and second passbands have two and three poles, respectively. The dual-band BPF has a simple structure and good performance. [ABSTRACT FROM AUTHOR]

Classification of individual tree species (ITS) is critical for fine-scale forest surveys. However, it is difficult to obtain the complete and high-precision data needed for ITS classification in large areas. Lower spatial resolution time-series imagery is more accessible than other types of imagery and contains rich phenological information. In this study, after delineating individual tree crowns using a 0.2-m unmanned aerial vehicle (UAV) image, we used 3-m time-series imagery and a new 3DLSTM model to identify ITS at the Gaofeng Forest Farm in Guangxi Province, China. The 3DLSTM ITS classification model combines three-dimensional convolutional neural network (3D CNN) and long short-term memory (LSTM) models; thus, spatial, multiband, and time-series information can be extracted simultaneously to identify ITS more accurately. In this study, when only 3-m Planet time-series imagery was used for classification, the 3DLSTM model offered an ITS classification accuracy of 92.68%, outperforming two ITS classifiers (DenseNet or AlexNet model) based on one individual image. Moreover, the 3DLSTM model was better at identifying broad-leaved tree species than other deeplearning models. The experimental results proved that ITS classification could be significantly improved using only 3DLSTM and time-series images, offering the possibility of classifying large-scale ITS at a low cost. [ABSTRACT FROM AUTHOR]

In this paper, a novel method was proposed to improve the production efficiency and formability of titanium alloy, which was named triple-layer sheet hot stamping with a cold die cooling (THF). The titanium alloy sheet was clamped by two steel sheets with no adhesive added, then heated, transferred and formed together. In order to verify the ability in enhancing formability of this process, spherical part forming tests were carried out to study the formability under the single-layer sheet hot stamping (SHF) and THF. Finally, a plug socket part was formed to verify the practicability of the novel forming process. The finite element (FE) model was established to analyze the forming process finding that the formability of the parts were significantly improved after using THF process. Comparing with SHF process, the stamping depth increases by 135.7% at 900 °C in the THF process. The forming limit strain increases from 0.18 of the single-layer sheet to 0.51 of the triple-layer sheet. The forming limit strain obtained by the THF process is close to that of isothermal forming. The friction state is one of the main reason for improving formability. Moreover, for plug socket parts, there is almost no thinning of the part in the THF process at 900 °C. In conclusion, it has great advantages in improving the formability of titanium alloy using the THF process. [ABSTRACT FROM AUTHOR]

The joint development of cultural heritage protection and tourism is an essential part of sustainable heritage tourism. Mount Lushan in China is such a site which in the past has had shortcomings in heritage protection and heritage tourism marketing. The present research addresses this issue by using digital technologies such as oblique aerial photography, 3D laser scanning technology, and 360 degrees panorama technology to digitize the Mount Lushan cultural landscape heritage site, integrating all elements to create a virtual tourism subsystem. It provides users with a virtual experience of cultural landscape heritage tourism and promotes cultural landscape tourism marketing. In addition, tourist flow and environmental subsystems were built through the integration of Internet of Things (IoT) technology and analytical models. The tourist flow subsystem can help managers to regulate tourist flow according to the tourist carrying capacity threshold. Managers can also conduct environmental health assessment and management through the "pressure-state-response" model provided by the environmental subsystem. Finally, a comprehensive platform was developed based on the system concept, which integrated the three subsystems and their functions, and developed different versions to provide a visual platform for tourists and managers. This study provides a new model for the joint development of cultural heritage protection and tourism activities. [ABSTRACT FROM AUTHOR]

Large-scale water and soil development in inland river basins in arid areas has made changes in landscape composition and structure, threatening the ecological balance. In order to study the trend of land use/cover and landscape pattern change and its relationship with water resources utilization in Manas River Basin, the land-use data of five periods in 1976, 1990, 2000, 2010 and 2015 were analyzed. The results showed that: (1) During 1976-2015, farmland and construction land continuously increased, forest land and grassland continuously decreased, the water area initially reduced and then increased, the area of saline-alkali land initially increased and then reduced, the overall trend of unused land and the sandy area was decreasing and the area of different time periods is floating. The areas of land-use types either increased or decreased. This indicates that the landscape pattern of the basin changes dramatically, and human activities are the main reasons for this phenomenon; (2) The oasis area increased from 3480.2 km2 in 1976 to 7982.0 km2 in 2015, with an obvious increasing trend. The oasis area clearly increased during 1976-1990, the growth rate was 40.6%, the growth rate of the oasis area was 129.4%. In the last 40 years, the degree of desertification fluctuated and decreased. The increase of the oasis area directly leads to the increase of water resources utilization and aggravates the degree of water resources shortage; (3) The pattern of land-use types showed a non-equilibrium trend. In the region with increasing landscape heterogeneity, the overall landscape pattern was increasingly controlled by the majority of patches. The intensive land management model and drip irrigation under mulch have improved the utilization efficiency of water resources and saved water resources from engineering renovation and irrigation management. [ABSTRACT FROM AUTHOR]