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Slope excavation quality assessment and excavated volume calculation in hydraulic projects based on laser scanning technology 被引量:5
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作者 Chao Hu Yi-hong Zhou +1 位作者 Chun-ju Zhao Zhi-guo Pan 《Water Science and Engineering》 EI CAS CSCD 2015年第2期164-173,共10页
Slope excavation is one of the most crucial steps in the construction of a hydraulic project. Excavation project quality assessment and excavated volume calculation are critical in construction management. The positio... Slope excavation is one of the most crucial steps in the construction of a hydraulic project. Excavation project quality assessment and excavated volume calculation are critical in construction management. The positioning of excavation projects using traditional instruments is inefficient and may cause error. To improve the efficiency and precision of calculation and assessment, three-dimensional laser scanning technology was used for slope excavation quality assessment. An efficient data acquisition, processing, and management workflow was presented in this study. Based on the quality control indices, including the average gradient, slope toe elevation, and overbreak and underbreak,cross-sectional quality assessment and holistic quality assessment methods were proposed to assess the slope excavation quality with laserscanned data. An algorithm was also presented to calculate the excavated volume with laser-scanned data. A field application and a laboratory experiment were carried out to verify the feasibility of these methods for excavation quality assessment and excavated volume calculation. The results show that the quality assessment indices can be obtained rapidly and accurately with design parameters and scanned data, and the results of holistic quality assessment are consistent with those of cross-sectional quality assessment. In addition, the time consumption in excavation quality assessment with the laser scanning technology can be reduced by 70%e90%, as compared with the traditional method. The excavated volume calculated with the scanned data only slightly differs from measured data, demonstrating the applicability of the excavated volume calculation method presented in this study. 展开更多
关键词 Slope excavation quality assessment Volume calculation Three-dimensional laser scanning technology
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大连市领导干部科技素质的调查报告 被引量:4
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作者 张爱君 吕郁嵩 《大连干部学刊》 2001年第1期36-38,共3页
With the method of questionary, the author has carried out careful investigation concerning the qualities of science and technology of Dalian municipal leading officials. It has basiclly reflected the degree of unders... With the method of questionary, the author has carried out careful investigation concerning the qualities of science and technology of Dalian municipal leading officials. It has basiclly reflected the degree of understanding and grasping of the policies and knowledge of science and technology by the leading officials in Dalian municipal organizations and cause units. Some of the questions have been proved by the experts which have rather strong effectiveness and comparably. 展开更多
关键词 Leading Officials Qualities of Science and technology A state’s prosperity depends on Science and Education
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A 10-MHz SOI-Based Face Shear Square Micromechanical Resonator
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作者 Tan-Loc Nguyen Jing-Fu Bao +2 位作者 Jun-Wen Jiang Yuan Ling Xin-Yi Li 《Journal of Electronic Science and Technology》 CAS 2014年第1期64-70,共7页
A 10-MHz face shear (FS) square micro- mechanical resonator based on silicon-on-insulator (SO1) technology is presented in this paper. In order to examine the improvement of quality factor as well as motional resi... A 10-MHz face shear (FS) square micro- mechanical resonator based on silicon-on-insulator (SO1) technology is presented in this paper. In order to examine the improvement of quality factor as well as motional resistance Rx in this structure, the center-stem anchor is employed in this study. The benefit of anchoring the square in the center, which is the nodal point, is that the energy losses through the anchor can be minimized. Hence, a quality factor value of 2.0 million and the motional resistance of 8.2 k~ can be obtained with an FS mode resonator via finite element (FE) simulation. The results show the significance of the FS mode in this design, not only in its structure but also in its square-extensional mode and Lame-mode. Additionally, an SOI-based fabrication process is proposed to support the design. 展开更多
关键词 Face shear mode finite elementsimulation micromechanicai resonator quality factor silicon-on-insulator technology.
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Performance of pond–wetland complexes as a preliminary processor of drinking water sources 被引量:10
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作者 Weidong Wang Jun Zheng +4 位作者 Zhongqiong Wang Rongbin Zhang Qinghua Chen Xinfeng Yu Chengqing Yin 《Journal of Environmental Sciences》 SCIE EI CAS CSCD 2016年第1期119-133,共15页
Shijiuyang Constructed Wetland(110 hm^2) is a drinking water source treatment wetland with primary structural units of ponds and plant-bed/ditch systems. The wetland can process about 250,000 tonnes of source water ... Shijiuyang Constructed Wetland(110 hm^2) is a drinking water source treatment wetland with primary structural units of ponds and plant-bed/ditch systems. The wetland can process about 250,000 tonnes of source water in the Xincheng River every day and supplies raw water for Shijiuyang Drinking Water Plant. Daily data for 28 months indicated that the major water quality indexes of source water had been improved by one grade. The percentage increase for dissolved oxygen and the removal rates of ammonia nitrogen, iron and manganese were 73.63%, 38.86%, 35.64%, and 22.14% respectively. The treatment performance weight of ponds and plant-bed/ditch systems was roughly equal but they treated different pollutants preferentially. Most water quality indexes had better treatment efficacy with increasing temperature and inlet concentrations. These results revealed that the pond–wetland complexes exhibited strong buffering capacity for source water quality improvement. The treatment cost of Shijiuyang Drinking Water Plant was reduced by about 30.3%. Regional rainfall significantly determined the external river water levels and adversely deteriorated the inlet water quality, thus suggesting that the "hidden" diffuse pollution in the multitudinous stream branches as well as their catchments should be the controlling emphases for river source water protection in the future. The combination of pond and plant-bed/ditch systems provides a successful paradigm for drinking water source pretreatment. Three other drinking water source treatment wetlands with ponds and plant-bed/ditch systems are in operation or construction in the stream networks of the Yangtze River Delta and more people will be benefited. 展开更多
关键词 Pond–wetland combination Plant-bed/ditch system Constructed root channel technology Semi-subsurface flow wetland Weighted comprehensive water quality index
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