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Copyright of Journal of Changzhou University (Natural Science Edition) / Changzhou Daxue Xuebao (Ziran Kexue Ban) is the property of Editorial Department of Journal of Changzhou University and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Journal of Engineering Geology / Gongcheng Dizhi Xuebao is the property of Journal of Engineering Geology and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Journal of Engineering Geology / Gongcheng Dizhi Xuebao is the property of Journal of Engineering Geology and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

In this paper, a method which based on multi-source remote sensing data was designed to estimate forest canopy height. An improved topographic correction model which was used for calculating based-GLAS canopy height was put forward with airborne LiDAR data, since surface topography directly impacts vegetation LiDAR waveforms and vegetation height retrieval. Then, with corrected GLAS footprints as input samples, forest canopy height in different ecological zones was estimated by support vector regression (SVR) model combining with MODIS imagery. Lastly, the accuracy of estimation results was verified using field survey data and airborne LiDAR canopy height. The result show: slope levels in the study area directly impacted based-GLAS canopy height estimation accuracy. The improved topographic correction model could relieve the influence of topography on based-GLAS canopy height estimation, and the RMSE of estimation result ranged from 3.25m to 3.48m. In different ecological zones, SVR model estimation accuracy was stable and the RMSE ranged from 6.41m to 7.56m. Compared with arithmetic mean height, Lorey's height was closest to the estimation result and the average estimated accuracy of 80.3% in different ecological zones. The average estimated accuracy verified with airborne LiDAR metric height was 79.5% and consistence with Lorey's height. [ABSTRACT FROM AUTHOR]

Copyright of Chinese Journal of Oncology is the property of Chinese Journal of Oncology / Zhonghua Zhongliu Zazhi and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Aiming at the problem of fatigue damage of leisure chairs, a leisure chair was designed based on ergonomics theory, and the geometric model was established. Methods to analyze the fatigue life of the leisure chair were summarized, and a method was proposed to analyze the fatigue life based on load time history of leisure chair. Then the transient mechanical analysis of the chair was carried out in ANSYS to find out the bars which stress are larger according to the QB/T 4191-2011 standard. Later, the model was verified and the load time histories of the dangerous bars were obtained in the virtual prototype. And the fatigue life analysis of the dangerous rods was conducted based on ANSYS and DesignLife. Finally, the prototype was made and tested. The result shows that the test results are consistent with the results of fatigue analysis, and the accuracy of the method which provides a reference for the related research and analysis is verified. [ABSTRACT FROM AUTHOR]

The forest vertical structure parameters can reflect the growth status of the forest and the species diversity of the forest to a certain extent. Forest canopy height is a significant part of vertical structure parameters, and quantification of its distribution is an active academic research focus in recent years due to its important significance for the forest ecosystem research. Spaceborne lidar system ICESat/GLAS, with laser sensor placed on the satellite, is the full waveform lidar altimeter system with a 1064 nm laser operated at 40 Hz. The return GLAS waveforms can describe the vertical distribution of the landscape. However, large footprint diameter can reshape the vertical extent of waveforms for topographic change. Airborne lidar system whose laser sensor is placed on the airplane can transmit a short duration laser pulse. There may be several secondary returns as the light from a single pulse is reflected from within canopy layers of vegetation. The property of high-density laser point cloud (0.5-10 points/m2) makes some airborne lidar metrics to be suitable predictors of either canopy height or even individual tree height. In this study, combining with the SRTMGL1 terrain data and airborne lidar point cloud data, GLAS-based canopy height correction model based on physical equation was proposed. The effect of slope on the estimation accuracy was analyzed and estimated result was validated in in situ data. An irregular triangulation algorithm was used to filter the point cloud to extract the ground point. The initial triangulation model was optimized by setting the angle threshold ε and the height threshold l. Point cloud normalized processing which eliminates the terrain effect could reflect the actual canopy height. The range of the GLAS footprint was used to extract the local maximum value of the normalized point cloud and analyzed canopy profile. This value was modeled as a true value for model parameters fitting by considering the slope, the footprint size and the surface roughness. GLAS-based canopy height indirectly was calculated from waveform parameters, it was necessary to use in situ data to analyze the estimated result. The result showed: airborne points cloud data can accurately reflect the distribution of forest canopy in the range of the GLAS footprint, but there were obvious differences in the distribution of points cloud in different forest types. By comparing uncorrected GLAS-based canopy height RH100 with airborne lidar canopy height, we found that the canopy height from RH100 was overestimated, which led to the positive bias. For the flat terrain cases, canopy and ground peak can be accurately identified from the waveform. GLAS metric RH100 can be approximately considered as forest canopy height because the last Gaussian peak was assumed to represent the ground peak. However, for the slope terrain case, the slope stretched the waveform, leading to increased waveform extent, and decreased canopy and ground peaks. For heterogeneous land surface cases, single slope information can not accurately reflect changes in the surface. The undulating surface made the waveform more complex. After topographic correction, not surprisingly, the fitting result of Hc was closer to the 1:1 fitting line. Reflecting on the root mean square error RMSE, uncorrected RMSE was 6.43 m greater than the corrected RMSE witch is 3.54 m. The effect of the topography was alleviated to a certain extent. As slope level increased, the RMSE of uncorrection increased from 3.55 m to 10.25 m, whereas the RMSE of correction had stabilized at between 3.26 m and 3.88 m. The effect of the topography was alleviated to a certain extent. Comparing with arithmetic average height, it can be seen that the estimation result was close to Lorey's height. In addition, the accuracy of canopy height estimation in different forest types was different, the accuracy of mixed forest was the highest (r and RMSE were 0.84 and1.06 m), and the accuracy of broad-leaved forest was the lowest (r and RMSE were 0.44 and 2.56 m). [ABSTRACT FROM AUTHOR]

Copyright of Journal of Engineering Geology / Gongcheng Dizhi Xuebao is the property of Journal of Engineering Geology and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Transactions of China Pulp & Paper is the property of China Pulp & Paper Magazines Publisher and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

At 16:30 on August 3rd, 2014, Ms 6.5 earthquake occurs in Ludian County of Zhaotong City,Yunnan Province, China. Ludian earthquake causes a wide spread of secondary mountain disasters including collapse, landslide, unstable slope, etc. By field investigation and interpretation of remote sensing images, there are 235 secondary mountain disasters, and the area is 8.59 km2. Based on GIS spatial analysis method, relationships between the distribution of secondary mountain disaster and earthquake were explained by secondary mountain disaster center number density and area percentage. The former is defined as the number of secondary mountaindisaster central point per square kilometer; the latter is defined as the percentage of the area affected by secondary mountain disasters. The effects of topography, river and rock on spatial distribution of secondary mountain disasters were discussed with the factors including elevation, slope, aspect, lithology and distance from the river.Secondary mountain disaster center number density is about 0.2 points per square kilometer, and area percentage is about 0.79%. The results show that the arrangement of secondary mountain disaster is controlled by the main fault of Zhaotong-Ludian with NE-orientation,and 63.83% of secondary mountain disasters happen in the region with a distance of 2-8 km to the causative fault; secondary mountain disasters mainly distribute in the areas with the elevation of 1000-1200 mand the slope of 35°-45°; secondary mountain disaster center number density and area percentage are maximum under the slope of 20°-30°; secondary mountain disasters develop mostly in hard rock strata such as carbonate rock, while steep slope secondary mountain disasters develop mostly in soft rock strata; secondary mountain disasters approximately distribute in a line along Niulan River, and the farther away from the river, the lower the probability of occurrence is. [ABSTRACT FROM AUTHOR]