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A New Method in Determining Potential Region of Precipitation Enhancement Above Coastal Land
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作者 WANG Yilin WU Wei 《Journal of Ocean University of China》 SCIE CAS 2010年第4期309-316,共8页
To ensure the effectiveness of the operation of artificial precipitation enhancement, a potential region for the operation should be determined in advance.As cloud microphysical measurements needed for the determinati... To ensure the effectiveness of the operation of artificial precipitation enhancement, a potential region for the operation should be determined in advance.As cloud microphysical measurements needed for the determination of the potential region of cloud seeding are not available before the operation of routine precipitation enhancement, a new method based on the growth process of ice crystal is put forward for determining the potential region using the numerical weather prediction model output.The ice supersaturation, accumulated water vapor within minus temperature layer (≥9 mm), and upward water vapor transportation are adopted as criteria to determine the potential time, height and region of cloud seeding, and the real-time radar images are applied to make decisions on the seeding commanding.The criteria and Doppler radar images are studied in a case of precipitation enhancement characterized by significant water vapor supply from the north part of a tropical cyclone in the northwest Pacific, which shows that the ocean plays a crucial role in the advection transportation of water vapor to the potential region of the coastal area.The study presents a new method to determine the potential region of precipitation enhancement using macro-physical quantities under ice crystal growth environment.The method possesses a clear physical significance and can be readily applied with the required and easily predicted parameters. 展开更多
关键词 precipitation enhancement criteria SEEDING potential region new method
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Applying artificial neural networks to achieve quantitative division of potential focal regions
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作者 姜效典 张维岗 《Acta Seismologica Sinica(English Edition)》 CSCD 1994年第4期645-652,共8页
There are put forward in this paper the principle of using artificial neural networks to determine the featureswhich reflect seismotectonics and seismicity of the potential focal regions and the method to divide quant... There are put forward in this paper the principle of using artificial neural networks to determine the featureswhich reflect seismotectonics and seismicity of the potential focal regions and the method to divide quantitativelythe potential focal regions. The calculation of the actual data of North China area shows that it may fully reveal the relations between the potential focal regions and their controling characteristics by the method, of which the principle is concise and convenient to apply, the calculated results reasonable, the division in a meticulous way and the achievement practicable. 展开更多
关键词 neural network potential focal region quantitative division
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Changes of evoked potential in different hippocampal regions induced by electrostimulation at medial mamillary nucleus of rats
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作者 Xinxin Li Lihong Shang +1 位作者 Liang Zhang Fengzhi Cui 《Neural Regeneration Research》 SCIE CAS CSCD 2006年第1期87-89,共3页
BACKGROUND: Morphological data have shown that the most important afferent fibers of papillary body come from hippocampal structure.OBJECTIVE: To observe the changes of evoked potential in hippocampus and the signif... BACKGROUND: Morphological data have shown that the most important afferent fibers of papillary body come from hippocampal structure.OBJECTIVE: To observe the changes of evoked potential in hippocampus and the significance after electrostimulation at medial mamillary nucleus. DESIGN: An observational control experiment.SETTING: Department of Physiology, Shenyang Medical College.MATERIALS : Twenty-three male or female Wistar rats, 3-4 months old, weighing 270-350 g, were provided by bhe animal room of Shenyang Medical College [the license number was scxk(Liao)2003-0016]. METHODS: The Wistar rats were anaesthetized by intraperintoneal injection of 20% urethane (1 g/kg), tracheal intubation was also given. The self-made double-pole metal stimulating electrode with the point diameter of 1 mm was inserted into medial mamillary nucleus, the wanted hippocampal guidance spot was found within the rang of the hippocampal region at the same side of tee mamillary body range (CA1-CA4), inserted with same-core guidance electrode, a sole square-wave stimulation of wave wide 0.2 ms stimulated with electrodes at the applied intensity of 7-9 V, the evoked potential was induced through guidance electrodes, and then input to the ATAC-350 data-processing machine for memory showing wave processing, the memory recorded wave recording graph was separately drawn up by the X-Y recording instrument to observe the latency, time procedure and amplitude of the evoked potential in each hippocampal region of the rats and calculate the percentage of the evoked potential in each hippocampal region. Totally 78 guidance spots in hippocampus were recorded, including 30 positive reaction spots and 48 negative ones. MAIN OUTCOME MEASURES: ① Latency, time procedure and amplitude of the evoked potentials in each hippocampal region of rats; ②percentage of the evoked potentials in each hippocampal region; ③ the wave shapes of the evoked potentials in each hippocampal region from different arrangement in the same positive reaction spot. RESULTS :① Of the 30 recorded positive reactions, 9 positive spots fused into the stimulated false marks because of the short latency. The analysis of variance showed that the latency had significant difference (P 〈 0.05), time procedure had highly significant difference (P 〈 0.01 ), but there was no significant difference in the amplitude (P 〉 0.05) among the hippampal regions.② Among the 30 positive spots, the percentage of evoked potential in the hippocampal regions were 34.5% for CA1, 2.0% for CA2, 24.1% for CA3 and 22.4% for CA4. ③ In different levels of the same positive spot, different changes of the evoked potential wave shapes could be observed, and the most obvious change was that of positive wave amplitude. At different positive spots, evoked potentials of positive phase, negative and the double-phase could be observed. CONCLUSION: There are nerve associations between mamillary body and hippocampus, afferent fibers of mamillary body come from hippocampal CA1 region are a little more. 展开更多
关键词 Changes of evoked potential in different hippocampal regions induced by electrostimulation at medial mamillary nucleus of rats body
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Ambient tectonic shear stress field in Southern California and seismic hazard regions 被引量:1
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作者 陈培善 肖磊 +1 位作者 白彤霞 成瑾 《Acta Seismologica Sinica(English Edition)》 CSCD 1998年第2期20-29,共10页
ccording to the fracture mechanics rupture model of earthquakes put forward by us, several equations to compute tectonic ambient shear stress value τ0 have been derived [equations (1), (2), (3), (5)].τ0 values for i... ccording to the fracture mechanics rupture model of earthquakes put forward by us, several equations to compute tectonic ambient shear stress value τ0 have been derived [equations (1), (2), (3), (5)].τ0 values for intermediate and small earthquakes occurred in Chinese mainland and Southern California have been calculated by use of these equations. The results demonstrate that the level and distribution of τ0 are closely related to the location where large earthquakes will occur, i.e. the region with higher level of τ0 will be prone to occur large earthquakes and the region with lower level will usually occur small earthquakes. According to the spatial distribution of τ0 , the seismic hazard regions or the potential earthquake source regions can in some degree be determined. According to the variation of τ0 with time, the large earthquake occurrence time can be roughly estimated. According to the distribution of τ0 in Southern California and variation with time, three high stress level regions are determined, one (Goldfield area) of them is the present seismic hazard region. 展开更多
关键词 tectonic ambient shear stress field Southern California seismic hazard region potential earthquake source region
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Investigation of the binding behavior of human serum albumin and phosphorothioate oligodeoxynucleotide
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作者 叶国柱 张亮仁 张礼和 《Journal of Chinese Pharmaceutical Sciences》 CAS 2007年第1期9-13,共5页
Aim To study the binding behavior between human serum albumin (HSA) and phosphorothioate oligodeoxynucleotide (PS- ODN) and the effects of bivalent cations on the interaction. Methods Surface plasma resonance, cir... Aim To study the binding behavior between human serum albumin (HSA) and phosphorothioate oligodeoxynucleotide (PS- ODN) and the effects of bivalent cations on the interaction. Methods Surface plasma resonance, circular dichroism and fluorescence experiments were conducted. Results ( 1 ) the binding ability was decreased along with the increase of pH; (2) Zn^2+and Ni^2+ enhanced the interaction between PS-ODN and HSA; (3) Upon PS-ODN binding, the conformation of HSA was changed with an increase of β - sheet. Conclusion The results provide experimental evidences to the hypothesis that PS-ODN binds with HSA in the positive potential region, and histidine residues located in the region play a crucial rule in the interaction. 展开更多
关键词 Phosphoruthioate oligodeoxynucleotide Human serum albumin Positive potential region Conformational changes
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静电场电位边值问题唯一性定理的补充与完整证明 被引量:1
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作者 陈文卿 闫述 《物理与工程》 2017年第6期54-59,共6页
本文对静电场电位边值问题与解的唯一性定理作了补充与完整的证明.首先将区域边界与衔接边界从通常的混称中区分开来,确认了静电场边值问题中第三类边界条件应有的形式,在解的唯一性定理中增加了衔接条件和无限远边界条件,并根据数学表... 本文对静电场电位边值问题与解的唯一性定理作了补充与完整的证明.首先将区域边界与衔接边界从通常的混称中区分开来,确认了静电场边值问题中第三类边界条件应有的形式,在解的唯一性定理中增加了衔接条件和无限远边界条件,并根据数学表达式的形式重新归类。然后在区域边界条件、无限远边界条件和衔接条件下电位解的唯一性的证明中,讨论了第一、第三类边值问题电位解的唯一性与全二类边界条件下电位存在常数差的问题,解除了第三类边界条件系数为正的限制,说明了整个求解空间为无限大时适用的边值问题。最后通过例题说明了区域、无限远和衔接3种边界条件在解题中的应用。补充后的定理可以更好地作为解题和后续学习的依据和基础。 展开更多
关键词 电位的边值问题 区域边界条件 衔接条件 唯一性定理 证明
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Theory and measurement model of administrative region potential from a perspective of administrative division adjustment:Taking Chongqing city as a case study 被引量:4
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作者 WANG Kaiyong WANG Fuyuan 《Journal of Geographical Sciences》 SCIE CSCD 2020年第8期1341-1362,共22页
There is a lack of basic theory and method to examine the effect of administrative division(AD) adjustment on the regional development. Based on the theory and practice of Chinese AD adjustments, the paper defined the... There is a lack of basic theory and method to examine the effect of administrative division(AD) adjustment on the regional development. Based on the theory and practice of Chinese AD adjustments, the paper defined the concept of administrative region potential(ARP) and developed the quantitative model to measure the ARP. Then, the model was validated taking Chongqing as an empirical case. The results show that:(1) the ARP consists of energy of position(i.e., geographic space factors) and gravitational potential energy(i.e., administrative levels and management system factors). Administrative division adjustment can change the ARP, thereby changing its path and driving force of regional development.(2) The ARP model of Chongqing city can reflect the effects of administrative division adjustment events on the Chongqing city objectively. Specifically, ARP includes variables of land jurisdiction, human capital level, fixed assets investment capacity, administrative hierarchy of fiscal decentralization and administrative decentralization.(3) The ARP promotion has significant positive influence on the performance of local economic development in Chongqing city.(4) Reasonable AD adjustments will help the region integrate production elements and resources, enhance the political power of the city, improve its ARP, and then promote local economic development. The ARP model is proved to be an efficient way to understand and explain the regional effect of AD adjustment. It provides a new analytical perspective for the planning of AD adjustment in various regions, and can also be used as a practical method for assessing the effects of AD adjustment. 展开更多
关键词 administrative division administrative region potential model regression analysis Chongqing city
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Fault-weakening effect of reservoir temperature of hot spring and its influence on seismic activities
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作者 林元武 《Acta Seismologica Sinica(English Edition)》 CSCD 1994年第2期321-330,共10页
In this paper, the reservoir temperatures of 14 hot spring samples collected from the northern segment of theRed River Fault are calculated by using the mixing-model of SiO2-geothermometer. Based on the features ofres... In this paper, the reservoir temperatures of 14 hot spring samples collected from the northern segment of theRed River Fault are calculated by using the mixing-model of SiO2-geothermometer. Based on the features ofreservoir temperatures and densities of hot springs, the northern segment of the Red River Fault is furtherdivided into 4 sub-segments. The influence of weakening effect of water on seismic activities is discussed fromthe view point of fault-weakening effect of water. It is suggested that the difference in seismic activity between various sub-segments is principally caused by the difference in intensity of the fault-weakening effect ofwater of these sub-segments. The Eryuan sub-segment where the reservoir temperatures are high and the hotsprings are dense corresponds to a slipped region, however, the Jianchuan and Midu sub-segments where thereservoir temperatures are lower and the hot springs are fewer as well as the Dan sub-segment where the hotspring are very few all correspond to locked regions. It is suggested that Dan sub-segment is the riskiest region for strong earthquake preparation, while the possibility for strong earthquake preparation is very little inthe Eryuan sub-segment. 展开更多
关键词 northern segment of the Red River Fault SiO_2-geothermometer reservoir temperature of hot Spring weakening effect seismicity potential earthquake source region
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Chemical characteristics of trace metals in PM10 and their concentrated weighted trajectory analysis at Central Delhi,India 被引量:1
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作者 Subhash Chandra Monika J.Kulshrestha +1 位作者 Ruchi Singh Nahar Singh 《Journal of Environmental Sciences》 SCIE EI CAS CSCD 2017年第5期184-196,共13页
Trace metals associated with PM10 aerosols and their variation during day and nighttime as well as during different seasons have been studied for the year 2012. PCA analysis suggested5 PCs,which accounted for 86.8% cu... Trace metals associated with PM10 aerosols and their variation during day and nighttime as well as during different seasons have been studied for the year 2012. PCA analysis suggested5 PCs,which accounted for 86.8% cumulative variance. PC1 accounted for 30% with a significant loading of metals of anthropogenic origin,while PC2 showed 28% variance with the loading of metals of crustal origin. These trace metals showed seasonal distinct day and night time characteristics. The concentrations of Cu,Pb,and Cd were found to be higher during nighttime in all the seasons. Only Fe was observed with significantly higher mean concentrations during daytime of all seasons except monsoon. The highest mean values of Cu,Cd,Zn,and Pb during post-monsoon might be attributed to winds advection over the regions of waste/biomass burning and industrial activities in Punjab and Haryana regions.Furthermore,concentration weighted trajectory analysis suggested that metals of crustal origin were contributed by long-range transport while metals of anthropogenic and industrial activities were contributed by regional/local source regions. 展开更多
关键词 Trace metals potential source regions Backward trajectory Principal component analysis
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Altitude of the upper boundary of AAR based on observations of ion beams in inverted-V structures:A case study 被引量:2
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作者 CUI YanBo FU SuiYan +5 位作者 ZONG QiuGang XIE Lun SUN WeiJie ZHAO Duo WU Tong George PARKS 《Science China Earth Sciences》 SCIE EI CAS CSCD 2016年第7期1489-1497,共9页
Outflowing ion beams forming four successive inverted-V structures in the energy-time spectrograms of H+, He+, and O+ were observed at an altitude of 3.4 RE by Cluster satellites travelling above the auroral accelerat... Outflowing ion beams forming four successive inverted-V structures in the energy-time spectrograms of H+, He+, and O+ were observed at an altitude of 3.4 RE by Cluster satellites travelling above the auroral acceleration region (AAR) in the southern hemisphere on February 14, 2001. Energization by negative U-shaped potential structures in the AAR is believed to be responsible for the formation of these outflowing ion inverted-V structures. Thus, utilizing the different motion properties of the three ion species, the altitude of the upper boundary of the AAR is estimated to be ~11100 km. Moreover, based on multi-satellite observations, each of these U-shaped potential structures involved in this event crosses the latitudinal direction at ~0.4°–1° invariantlatitude (ILAT), moving poleward at an average speed of ~0.2° ILAT per minute, before disappearing at ~71.5° ILAT. 展开更多
关键词 Outflowing ion beams Inverted-V structure Auroral acceleration region U-shaped potential structure Altitude of upper boundary
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