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A Method for Surveying Control Network Optimization Based on Reliability Properties 被引量:4
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作者 ZHANG Zhenglu DENG Yong LUO Changlin 《Geo-Spatial Information Science》 2007年第4期235-239,共5页
Surveying control network optimization design is related to standards, such as precision, reliability, sensitivity and the cost, and these standards are related closely to each other. A new method for surveying contro... Surveying control network optimization design is related to standards, such as precision, reliability, sensitivity and the cost, and these standards are related closely to each other. A new method for surveying control network simulation optimization design is proposed. This method is based on the inner reliability index of the observation values. 展开更多
关键词 surveying control network optimization design RELIABILITY redundant observation weight
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Discussion on Application of 3S Technologies in Cadastral Surveying and Mapping
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作者 Yonghua ZHAO 《Agricultural Biotechnology》 CAS 2021年第3期97-100,共4页
In order to explore the application of 3S technologies in modern urban cadastral surveying and mapping,we analyzed the equipment composition of the global positioning system,the advantages of GPS surveying and mapping... In order to explore the application of 3S technologies in modern urban cadastral surveying and mapping,we analyzed the equipment composition of the global positioning system,the advantages of GPS surveying and mapping technology,and the main functions of RS and GIS technologies.GPS technology can improve the accuracy of boundary points of surveying and mapping areas,thereby improving the efficiency of surveying and mapping work and the accuracy of surveying and mapping information;remote sensing surveying and mapping technology has a large observation range and observation space,and RS technology can be used to collect data in remote mountainous areas to reduce the cost of manpower and material resources in surveying and mapping work;and GIS technology provides important data support for land planning and ownership definition.3S technologies optimize and streamline the surveying and mapping process with their own advantages,making the cadastral surveying and mapping work more scientific and efficient. 展开更多
关键词 Cadastral survey GPS RS GIS Control survey
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Chinese Surveying and Control Network for Earth-Orbit Satellites and Deep Space Detection
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作者 WEI Erhu LIU Jingnan SHI Chuang 《Geo-Spatial Information Science》 2006年第1期6-12,37,共8页
The relationship between the surveying and contro l network(CSN) for earth-orbit satellite and spatial geodesy, and the relationshi p between the CSN for deep space celestial bodies and detectors, and deep space detec... The relationship between the surveying and contro l network(CSN) for earth-orbit satellite and spatial geodesy, and the relationshi p between the CSN for deep space celestial bodies and detectors, and deep space detection are briefly summarized, and so are the basic technical needs of the de ep space surveying and control network(DSN). Then, the techniques, the constitue nts and the distributing of Chinese satellite CSN (CSCSN) and other radio observ ing establishments in China are introduced. Lastly, with the primary CSCSN and o ther observing establishments, some projects for China to rebuild a more perfect CSCSN, and to establish a DSN are analyzed and stated. 展开更多
关键词 satellite surveying and control network DSN microwave radio radar LLR DSCCs radio observation space-based station
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PRECISE LEVELING OF THE VERY LONG QINLING MOUNTAIN TUNNEL 被引量:1
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作者 ZHANG Zhenglu YANG Zhentao XU Shaoquan ZHANG Xiangduo 《Geo-Spatial Information Science》 2000年第1期57-61,共5页
The Qinling tunnel with length of 18. 488km is located on the railway line from Xi’ an (Shanxi Province) to Ankan (Sichuan Province) in the middle of Qinling moun- tain. It is the longest double track railway tunnel ... The Qinling tunnel with length of 18. 488km is located on the railway line from Xi’ an (Shanxi Province) to Ankan (Sichuan Province) in the middle of Qinling moun- tain. It is the longest double track railway tunnel in China and takes the third place in the world. According to the design, the break-through error in vertical direction caused by the al- timetric control surveying is limited to 18mm for the case of one piercing face. Because the leveling route reaches over 120km in length and must go over two mountains in 2 800m height, the first-order precise leveling and precise gravity measurement should be carried out in the construction stage. In this paper the field leveling approach, the application of new technology,some experience as well as the office calculation with final results analysis are in- troduced. By meticulous planning, organization and observation, the final accuracy of vertical difference between two tunnel end points is only 8mm, and it provides reliable surveying guarantee for this great tunnel engineering. Finally it is pointed out that this vertical differ- ence distinguishes obviously from the primary measurement result as high as 114mm. It means that the primary result is not accurate enough. 展开更多
关键词 TUNNEL break-through error vertical control surveying gravity measurement
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Parental Occupational Exposure and Risk of Acute Leukemia in Children: A Tunisian Population-Based Case-Control Study 被引量:1
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作者 H. Kalboussi Y. Ben Youssef +10 位作者 I. Bougmiza F. Aloui A. Aloui W. Boughattas M. Maoua A. Brahem S. Chatti O. El Maalel F. Debbabi A. Khlif N. Mrizak 《International Journal of Clinical Medicine》 2016年第3期193-203,共11页
Background: In recent decades, the incidence of children’s hematological malignancies has been increasing worldwide including Tunisia. Their severity is reflected in the importance of the medical, social and economic... Background: In recent decades, the incidence of children’s hematological malignancies has been increasing worldwide including Tunisia. Their severity is reflected in the importance of the medical, social and economic impact. This increase remains fully unexplained, and the involvement of genetic, environmental and occupational factors is strongly suspected. Materials and methods: Our study was a cross-sectional survey of the type case-control conducted in the University Hospital of Farhat Hached of Sousse during the period ranging between 1 July 2011 and 30 June 2012, and which included children with acute leukemia compared to children unharmed by neoplastic disease. Cases and controls were matched by age and gender. Our objective was to describe the socio-occupational characteristics of the parents of children with acute leukemia and to identify potential occupational factors implicated in the genesis of acute leukemia. Results: The number of acute leukemia cases in the Hematology Service and day hospital of the University Hospital of Farhat Hached during the study period was 66 cases divided into in 40 boys and 26 girls with a sex ratio of 1.53. Our cases and controls were matched by age and gender. The risk of incidence of leukemia in children from smoking fathers was higher (p = 0.02, OR = 2.24, IC = [1.11 - 4.52]). The risk of incidence of leukemia in children from alcoholic fathers was higher with p = 0.009, OR = 3.9;CI = [1.33 - 11.39]. After adjusting different variables, the difference persisted significantly with pa = 0.03 and ORa = 3.5, ICa = [1.09 - 11.6]. 25.7% of cases had a family history of blood disease and neoplasia, whereas no control presented that. The difference was statistically significant (p = 0.006, OR = 1.46, IC = [1.38 - 1.56]). The parental occupational exposures associated to the occurrence of acute leukemia in children were pesticides with a statistically significant difference (p = 0.03, OR = 2.94, IC = [1.06 - 8.13]). This difference persisted after adjustment with different variables pa = 0.01, ORa 3.75;ICa = [1.27 - 11.03]. This difference had become significant after adjustment with the different variables pa = 0.03, ORa = 2.67, ICa = [1.06 - 6.7]. Conclusion: Our results showed some support for a positive association between childhood acute leukemia risk and parental occupational exposure to pesticides and cement. Additionally, acute leukemia risk among children might be increased with parental alcohol consumption. 展开更多
关键词 Occupational Medicine HEMATOLOGY LEUKEMIA CHILDREN Case Control survey
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Survey and Practice of Reporting Quality of Randomized Controlled Clinical Trials on Traditional Chinese Medicine 被引量:1
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作者 李廷谦 毛兵 +2 位作者 王刚 常静 王蕾 《Chinese Journal of Integrative Medicine》 SCIE CAS 2008年第1期6-9,共4页
Evidence obtained from randomized controlled trials (RCTs) has been generally accepted as the gold standard in the evaluation of clinical effectiveness. Readers need to understand the trial design, implement... Evidence obtained from randomized controlled trials (RCTs) has been generally accepted as the gold standard in the evaluation of clinical effectiveness. Readers need to understand the trial design, implementation, results, analysis and interpretation, so as to fully Jnderstand the results of RCTs. Thus, the investigators of RCTs have to report these items in a complete, accurate and clear manner. Since 1998, we have conducted several evaluations on the reporting quality of RCTs published in Chinese journals on traditional Chinese medicine (TCM) and results have shown that there is an urgent need for higher quality RCTs on TCM. 展开更多
关键词 TCM In survey and Practice of Reporting Quality of Randomized controlled Clinical Trials on Traditional Chinese Medicine CONSORT
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Hazard Analysis and Primary Prevention and Treatment Report of Diseases and Pests in Export Blueberry Base in Majiang County
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作者 Wang Tao Ren Yanling +11 位作者 Liao Jiongfeng Zhang Yi Wang Jiayin Yang Feng Wang Juan Wang Kejia Zhang Yibo Chen Xiao Wang Xingning Cai Qiu Xu Ning Ou Houding 《Plant Diseases and Pests》 CAS 2016年第3期6-10,共5页
To fully understand occurrence and damage status of pests and diseases in export blueberry,systematic survey was conducted in Majiang export blueberry bases in Guizhou Province from 2012 to 2015. A total of 21 kinds o... To fully understand occurrence and damage status of pests and diseases in export blueberry,systematic survey was conducted in Majiang export blueberry bases in Guizhou Province from 2012 to 2015. A total of 21 kinds of pests and diseases were found on blueberry,including 10 kinds of diseases and 11 kinds of pests. Comprehensive analysis of pests and diseases and their damage degree revealed that pests and diseases causing severe damage were gray mold,scarab and fruit fly,while gray mold and fruit fly might seriously affect the export of blueberry. The prevention and control measures against gray mold and fruit fly were summarized. 展开更多
关键词 Export Blueberry Pests and Diseases survey Control
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