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Frequency Structures Vibration Identified by an Adaptative Filtering Techiques Applied on GPS L1 Signal
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作者 Ana Paula C.Larocca Ricardo E.Schaal +2 位作者 Gabriel do N.Guimaraes Igor Machado da Silveira Paulo César Lima Segantine 《Positioning》 2013年第2期137-143,共7页
This paper is part of a research under enhancement since 2001, in which the main objective is to measure small dynamic displacements by analysis of L1 GPS carrier frequency with 1575.42 MHz—wavelength 19.05 cm, under... This paper is part of a research under enhancement since 2001, in which the main objective is to measure small dynamic displacements by analysis of L1 GPS carrier frequency with 1575.42 MHz—wavelength 19.05 cm, under an adaptive method for collecting data and filtering techniques. This method, named Phase Residual Method (PRM) is based on the frequency domain analysis of the phase residuals resulted from the L1 double difference static data processing of two satellites in almost orthogonal elevation angle. In this work it is proposed to obtain the phase residuals directly from the raw phase observable collected in a short baseline during a limited time span, in lieu of obtaining the residual data file from regular GPS processing programs. In order to improve the ability to detect millimetric displacements, two filtering techniques are introduced. The first one is the autocorrelation that reduces the phase noise with random time behavior. The other one is the running mean to separate low frequency from the high frequency phase sources. Two trials are presented to verify the proposed method and filtering techniques applied. One simulates a 2.5 millimeter vertical GPS antenna displacement and the second using the data collected during a bridge dynamic load test. The results show a good consistency to detect millimetric oscillations from L1 frequency and filtering techniques. 展开更多
关键词 L1 GPS frequency Processing Filtering Techniques Millimetric Displacements Single frequency Receiver
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HNA-1 a and HNA-1 b gene frequencies in the Tunisian Blacks
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《中国输血杂志》 CAS CSCD 2001年第S1期366-,共1页
关键词 HNA-1 a and HNA-1 b gene frequencies in the Tunisian Blacks GENE
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A Positive Correlation between Elevated Altitude and Frequency of Mutant Alleles at the EPAS1 and HBB Loci in Chinese Indigenous Dogs 被引量:4
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作者 Ruoxi Fan Fei Liu +5 位作者 Hong Wu Shifang Wu Chunling Zhu Yan Li Guodong Wang Yaping Zhang 《Journal of Genetics and Genomics》 SCIE CAS CSCD 2015年第4期173-177,共5页
Hypoxia represents one of the most extreme environmental conditions for both human beings and animals living at high al- titudes (Zhao et al., 2009). Over the past few years, great attention has been focused on the ... Hypoxia represents one of the most extreme environmental conditions for both human beings and animals living at high al- titudes (Zhao et al., 2009). Over the past few years, great attention has been focused on the genetic bases of adaption to high-altitude environments (Bigham et al., 2010; Simonson et al., 2010). The domestic dog (Canisfamiliaris) is the first animal that developed an intimate relationship with human beings. Dogs migrated with human beings and have adapted to variety of ecological niches (Savolainen et al., 2002). Our previous research revealed parallel evolution and convergent evolution in the adaptation of dogs and humans to the high-altitude environment of the Tibetan plateau (Wang et al., 2013, 2014), suggesting that exploring the adaption of domestic dogs to high-altitude hypoxia is an interesting and important question. 展开更多
关键词 HBB PAS A Positive Correlation between Elevated Altitude and frequency of Mutant Alleles at the EPAS1 and HBB Loci in Chinese Indigenous Dogs
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EXPERIMENTAL STUDY ON PREVENTING FLOOD OF 1% FREQUENCY IN HUAIHE RIVER
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作者 Chen Xian pu, Liang Bin, Shao Dong chao, Wang Xia Anhui & Huaihe River Water Resources Research Institute, Bengbu 233000, P.R.China Duan Hong dong, Chen Biao Huaihe River Planning & Design Institute, Bengbu 233001, P.R.China 《Journal of Hydrodynamics》 SCIE EI CSCD 1999年第4期2-9,共8页
After having completed river regulation work in recent years, the dike distance up the reach of Lutaizi has been extended to 1.5 2.0 km in the Huaihe river. When the middle flood happened,such as those in 1956, 1982 ... After having completed river regulation work in recent years, the dike distance up the reach of Lutaizi has been extended to 1.5 2.0 km in the Huaihe river. When the middle flood happened,such as those in 1956, 1982 and 1991, flood can pass through safely. If the flood of 1% frequency happens, the flood discharge at Lutaizi will be larger than safe flood discharge 10000 m 3/s in downstream Lutaizi. By storing flood with the Linhuaigang sluice, the discharge of Lutaizi will not be over 10000 m 3/s. Cities in downstream Lutaizi will be free from flood. 展开更多
关键词 flood control model the flood of 1% frequency Linhuaigang flood control project Huaihe river
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Non-Invasive Treatment to Grade 1 Essential Hypertension by Percutaneous Laser and Electric Pulse to Acupoint with Music:A Randomized Controlled Trial 被引量:3
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作者 詹鸿锐 洪仲思 +5 位作者 陈奕伸 洪海裕 翁泽滨 杨璋斌 师晶丽 陈仲本 《Chinese Journal of Integrative Medicine》 SCIE CAS CSCD 2016年第9期696-703,共8页
Objective: To study a non-drug therapy for hypertension disease by combining percutaneous laser and electric pulse stimulation to acupoint with music, and to test the efficiency of the combining treatment to grade 1 ... Objective: To study a non-drug therapy for hypertension disease by combining percutaneous laser and electric pulse stimulation to acupoint with music, and to test the efficiency of the combining treatment to grade 1 essential hypertension. Methods: A total of 174 patients with grade 1 essential hypertension were randomly assigned to 3 groups with a random number table after Chinese medicine(CM) syndrome differentiation: the photoelectric and musical treatment group(Group 1, with a self-developed multi-mode audio frequency pulse photoelectric therapeutic apparatus), acupuncture group(Group 2), and oral placebo group(Group 3), 58 cases per group. The curative effect of each group was evaluated by the changes of blood pressure and CM syndrome integral before and after treatment. Results: Compared with Group 3, there were significant decrease of blood pressure and CM syndrome integral in Group 1 and Group 2(P〈0.01). Compared with Group 2, Group 1 showed the highest decrease in systolic pressure(P〈0.017). The total effective rate of anti-hypertension in Group 1(91.38%, 53/58) was significantly higher than that in Group 2(74.13%, 43/58) and Group 3(18.97%, 11/58, P〈0.05 or P〈0.01); and that in Group 2 was also significantly higher than that in Group 3(P〈0.01). There were significant difference in the total effective rate of CM syndrome integral in both Group 1(93.10%, 54/58) and Group 2(84.48%, 49/58) as compared with Group 3(17.24%, 10/58, P〈0.01), while there was no significant difference between Group 1 and Group 2(P〉0.05). Conclusions: The multi-mode audio frequency pulse photoelectric therapeutic apparatus, combining music, laser and electric pulse stimulation, is clinically useful for grade 1 essential hypertension. This "three in one" therapy method is non-invasive, easy and simple to handle. It is expected to be popularized as a new alternative treatment. 展开更多
关键词 laser and electric pulse stimulation to acupoint musical treatment multi-mode audio frequency pulse photoelectric therapeutic apparatus grade 1 essential hypertension
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Nighttime electron density enhancements at middle and low latitudes in East Asia 被引量:2
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作者 ZHANG YanYan LIU LiBo +3 位作者 CHEN YiDing LIU Jing YU You LI Ming 《Science China Earth Sciences》 SCIE EI CAS CSCD 2015年第4期551-561,共11页
Nighttime enhancements in ionospheric electron density at mid- and low-latitudes are investigated by using the critical frequency of the F2-1ayer (foF2) data measured from ionosonde stations at Okinawa (26.3°N... Nighttime enhancements in ionospheric electron density at mid- and low-latitudes are investigated by using the critical frequency of the F2-1ayer (foF2) data measured from ionosonde stations at Okinawa (26.3°N, 127.8°E, Geomagnetic 15.3°N), Yamagawa (31.2°N, 130.6°E, Geomagnetic 20.4°N), Kokubunji (35.7°N, 139.5°E, Geomagnetic 25.5°N), and Wakkanai (45.4°N, 141.7°E, Geomagnetic 35.4°N) in East Asia during several solar cycles. The results show that there are obvious seasonal and solar activity dependencies of the nighttime electron density enhancements. The enhancements are termed pre-midnight enhancement and post-midnight enhancement, according to the local time when the enhancement appeared. The former has a higher occurrence probability in summer months than in winter months. In contrast, the latter has a larger occurrence probability in winter months than in summer months. Moreover, the nighttime enhancements in electron density are more likely to occur at lower solar activity. These seasonal and solar activity variations of the nighttime enhancements in electron density can be explained in terms of the combined effects of downward plasma flux from the plasmasphere and the neutral winds. 展开更多
关键词 nighttime electron density enhancements critical frequency of the F2-1ayer seasonal and solar activity dependencies vertical equivalent winds
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