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A new model describing Forbush Decreases at Mars: combining the heliospheric modulation and the atmospheric influence 被引量:1
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作者 Jingnan Guo Robert FWimmer-Schweingruber +2 位作者 Mateja Dumbović Bernd Heber YuMing Wang 《Earth and Planetary Physics》 CSCD 2020年第1期62-72,共11页
Forbush decreases are depressions in the galactic cosmic rays (GCRs) that are caused primarily by modulations of interplanetary coronal mass ejections (ICMEs) but also occasionally by stream/corotating interaction reg... Forbush decreases are depressions in the galactic cosmic rays (GCRs) that are caused primarily by modulations of interplanetary coronal mass ejections (ICMEs) but also occasionally by stream/corotating interaction regions (SIRs/CIRs). Forbush decreases have been studied extensively using neutron monitors at Earth;recently, for the first time, they have been measured on the surface of another planet, Mars, by the Radiation Assessment Detector (RAD) on board the Mars Science Laboratory’s (MSL) rover Curiosity. The modulation of GCR particles by heliospheric transients in space is energy-dependent;afterwards, these particles interact with the Martian atmosphere, the interaction process depending on particle type and energy. In order to use ground-measured Forbush decreases to study the space weather environment near Mars, it is important to understand and quantify the energy-dependent modulation of the GCR particles by not only the pass-by heliospheric disturbances but also by the Martian atmosphere. Accordingly, this study presents a model that quantifies both at the Martian surface and in the interplanetary space near Mars the amplitudes of Forbush decreases at Mars during the pass-by of an ICME/SIR by combining the heliospheric modulation of GCRs with the atmospheric modification of such modulated GCR spectra. The modeled results are in good agreement with measurements of Forbush decreases caused by ICMEs/SIRs based on data collected by MSL on the surface of Mars and by the Mars Atmosphere and Volatile EvolutioN (MAVEN) spacecraft in orbit. Our model and these findings support the validity of both the Forbush decrease description and Martian atmospheric transport models. 展开更多
关键词 ICME and Forbush decreases space weather at Mars Mars:atmosphere GCR radiation
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Evolution of microstructure and texture of AZ80 magnesium alloy under hot torsion with constant decreasing temperature rate
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作者 Yongbiao Yang Jinxuan Guo +4 位作者 Cuiying Wang Wenxuan Jiang Zhimin Zhang Qiang Wang Xing Zhang 《Journal of Magnesium and Alloys》 SCIE EI CAS CSCD 2024年第4期1619-1637,共19页
Hot torsion tests for AZ80 magnesium alloy were carried out in the temperature range of 380℃-260℃,with a constant decreasing temperature rate of 10℃/s in order to weaken the basal texture and refine the grains.The ... Hot torsion tests for AZ80 magnesium alloy were carried out in the temperature range of 380℃-260℃,with a constant decreasing temperature rate of 10℃/s in order to weaken the basal texture and refine the grains.The results indicated that the average grain sizes were refined forming gradient structure with increasing specimen radial position from center(12.2-5.4μm),and that the initial basal texture intensity of the extruded magnesium alloy was weakened from 46.2 to 8.3.Furthermore,the extension twins(ETs)could be disintegrated from the twins forming separated twins with smaller sizes.Interestingly,ETs with the same twin variant intersecting with each other could be coalesced forming grains with similar orientation,while ETs with different twin variants were separated by twins boundaries contributing to grain refinement.Moreover,in addition to the conventional continuous dynamic recrystallized(CDRX)grains with 30˚orientation rotated around C-axis of the parent grains,CDRXed grains with 30˚rotation around a-axis and random rotation axis were also discerned.Besides,the CDRX evolution induced twins were also elaborated,exhibiting the complex competition between CDRX and twining.Hot torsion deformation with constant decreasing temperatures rate is an effective way of grain refinement and texture modification. 展开更多
关键词 Texture Microstructure Hot torsion Decreasing temperature AZ80
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Load-bearing characteristics and energy evolution of fractured rock masses after granite and sandstone grouting
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作者 WU Xu-kun ZHAO Guang-ming +4 位作者 MENG Xiang-rui LIU Chong-yan LIU Zhi-xi HUANG Shun-jie ZHANG Qi-hang 《Journal of Central South University》 SCIE EI CAS CSCD 2024年第8期2810-2825,共16页
Experiments on grouting-reinforced rock mass specimens with different particle sizes and features were carried out in this study to examine the effects of grouting reinforcement on the load-bearing characteristics of ... Experiments on grouting-reinforced rock mass specimens with different particle sizes and features were carried out in this study to examine the effects of grouting reinforcement on the load-bearing characteristics of fractured rock mass.The strength and deformation features of grouting-reinforced rock mass were analyzed under different loading manners;the energy evolution mechanism of grouting-reinforced rock mass specimens with different particle sizes and features was investigated;the energy dissipation ratio and post-peak stress decreasing rate were employed to evaluate the bearing stability of grouting-reinforced rock mass.The results show that the strength and ductility of granite-reinforced rock mass(GRM)under biaxial loading are higher than that of sandstone-reinforced rock mass(SRM)under uniaxial loading.Besides,the energy evolution characteristics of grouting-reinforced rock mass under uniaxial and biaxial loading mainly could be divided into early,middle,and late stages.In the early stage,total,elastic,and dissipation energies were quite small with flatter curves;in the middle stage,elastic energy increased rapidly,whereas dissipation energy increased slowly;in the late stage,dissipation energy increased sharply.The energy dissipation ratio was used to represent the pre-peak plastic deformation.Under uniaxial loading,this ratio increased as the particle size increased and the pre-peak plastic deformation of grouting-reinforced rock mass became larger;under biaxial loading,it dropped as the particle size increased,and the pre-peak plastic deformation of grouting-reinforced rock mass became smaller.The post-peak stress decline rate A_(v) was used to assess the post-peak bearing performance of grouting-reinforced rock mass.Under uniaxial loading,parameter A_(v) exhibited reduction as the particle size kept increasing,and the ability of post-peak of grouting-reinforced rock mass to allow deformation development was greater,and the bearing capacity was greater;under biaxial loading,A_(v) increased with the particle size,and the ability of post-peak of grouting-reinforced rock mass to allow deformation development was low and the bearing capacity was reduced.The findings are considered instrumental in improving the stability of the roadway-surrounding rock by granite and sandstone grouting. 展开更多
关键词 grouting-reinforced rock mass particle size energy dissipation ratio post-peak stress decreasing rate load-bearing characteristics
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RPL-Based IoT Networks under Decreased Rank Attack:Performance Analysis in Static and Mobile Environments
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作者 Amal Hkiri Mouna Karmani +3 位作者 Omar Ben Bahri Ahmed Mohammed Murayr Fawaz Hassan Alasmari Mohsen Machhout 《Computers, Materials & Continua》 SCIE EI 2024年第1期227-247,共21页
The RPL(IPv6 Routing Protocol for Low-Power and Lossy Networks)protocol is essential for efficient communi-cation within the Internet of Things(IoT)ecosystem.Despite its significance,RPL’s susceptibility to attacks r... The RPL(IPv6 Routing Protocol for Low-Power and Lossy Networks)protocol is essential for efficient communi-cation within the Internet of Things(IoT)ecosystem.Despite its significance,RPL’s susceptibility to attacks remains a concern.This paper presents a comprehensive simulation-based analysis of the RPL protocol’s vulnerability to the decreased rank attack in both static andmobilenetwork environments.We employ the Random Direction Mobility Model(RDM)for mobile scenarios within the Cooja simulator.Our systematic evaluation focuses on critical performance metrics,including Packet Delivery Ratio(PDR),Average End to End Delay(AE2ED),throughput,Expected Transmission Count(ETX),and Average Power Consumption(APC).Our findings illuminate the disruptive impact of this attack on the routing hierarchy,resulting in decreased PDR and throughput,increased AE2ED,ETX,and APC.These results underscore the urgent need for robust security measures to protect RPL-based IoT networks.Furthermore,our study emphasizes the exacerbated impact of the attack in mobile scenarios,highlighting the evolving security requirements of IoT networks. 展开更多
关键词 RPL decreased rank attacks MOBILITY random direction model
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Analysis of Forbush decreases observed using a muon telescope in Antarctica starting on 21 June 2015
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作者 De-Hong Huang Hong-Qiao Hu +4 位作者 Ji-Long Zhang Hong Lu Da-Li Zhang Bin-Shen Xue Jing-Tian Lu 《Chinese Physics C》 SCIE CAS CSCD 2018年第12期140-150,共11页
A cosmic-ray muon telescope the telescope was built in the Zhongshan has been collecting data since the end Station of Antarctica. The telescope of 2014, which was shortly after is the first observation device to be b... A cosmic-ray muon telescope the telescope was built in the Zhongshan has been collecting data since the end Station of Antarctica. The telescope of 2014, which was shortly after is the first observation device to be built by Chinese scientists in Antarctica. The pressure change is very strong in Zhongshan station. The count rate of the pressure correction results shows that the large variations in the count rate are likely caused by pressure fluctuations. During the period from 18 June to 22 June 2015, four halo coronal mass ejections (CMEs) were ejected from the Sun. These CMEs initiated a series of Forbush decreases (FD) when they reached the Earth. We conducted a comprehensive study of the intensity fluctuations of galactic cosmic rays recorded during FDs. The intensity fluctuations used in this study were collected by cosmic ray detectors of multiple stations (Zhongshan, McMurdo, South Polar, and Nagoya), and the solar wind measurements were collected by ACE and WIND. The profile of the FD of 22 June demonstrated a four-step decrease. The traditional one- or two-step FD classification method does not adequately explain the FD profile results. The interaction between the faster CME that occurred on 21 June 2015 and the two slow CMEs of the earlier few days should be considered. The cosmic ray intensities of the South Pole, McMurdo, and Zhongshan stations have similar hourly variations, whereas the galactic cosmic rays recorded between polar and non-polar locations are distinct. The FD pre-increase of 22 June 2015 for the Nagoya ninon telescope (non-polar location) lags those of the McMurdo and Zhongshan stations (polar locations) by 1 h. The FD onset of 22 June 2015 for the Nagoya muon telescope lags those of the polar locations by 1 h. 展开更多
关键词 cosmic ray muon telescope neutron monitor CME Forbush decrease
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Non-harmonic resonance of viscoelastic structures subjected to time-dependent exponentially decreasing transverse distributed loads
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作者 Nasrin Jafari 《Earthquake Engineering and Engineering Vibration》 SCIE EI CSCD 2023年第3期825-840,共16页
In this paper,the non-harmonic resonance of Bernoulli viscoelastic beams,Kirchhoff viscoelastic plates,Timoshenko viscoelastic beams,and Mindlin viscoelastic plates subjected to time-dependent exponentially decreasing... In this paper,the non-harmonic resonance of Bernoulli viscoelastic beams,Kirchhoff viscoelastic plates,Timoshenko viscoelastic beams,and Mindlin viscoelastic plates subjected to time-dependent exponentially decreasing transverse distributed load is investigated for the first time.The constitutive equations are expressed utilizing Boltzmann integral law with a constant bulk modulus.The displacement vector is approximated by employing the separation of variables method.The Laplace transformation is used to transfer equations from the time domain to the Laplace domain and vice versa.The novel point of the proposed method is to express,prove and calculate the critical time in which the displacement will be several times the displacement at time zero.In addition,this new method calculates the maximum deflection at the critical time,explicitly and exactly,without any need to follow the time-displacement curve with a low computational cost.Additionally,the proposed method introduces the critical range of time so that the responses are greater than the responses at time zero. 展开更多
关键词 Bernoulli and Timoshenko viscoelastic beams critical time non-harmonic resonance time-dependent decreasing exponential load Kirchhoff and Mindlin viscoelastic plates
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Creating Smart House via IoT and Intelligent Computation
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作者 Wen-Tsai Sung Sung-Jung Hsiao 《Intelligent Automation & Soft Computing》 SCIE 2023年第1期415-430,共16页
This study mainly uses the concept of the Internet of Things(IoT)to establish a smart house with an indoor,comfortable,environmental,and real-time monitoring system.In the smart house,this investigation employed the t... This study mainly uses the concept of the Internet of Things(IoT)to establish a smart house with an indoor,comfortable,environmental,and real-time monitoring system.In the smart house,this investigation employed the temperature-and humidity-sensing module and the lightness module to monitor any con-dition for an intelligent-living house.The data of temperature,humidity,and lightness are transmitted wirelessly to the human-machine interface.The correlation of the weight of the extension theory is used to analyze the ideal and comfortable environment so that people in the indoor environment can feel better thermal comfort and lightness.In this study,improved particle swarm optimization(IPSO)is employed—an effective evolutionary method used to search the function extreme.It is simple and has a fast convergence.The convergence accuracy of this algorithm is not high at the beginning,and it can easily fall into the local extreme points.The effect of the inertia weight in mix extension theory and PSO becomes IPSO-Extension Neural Network(ENN),which was analyzed and found reliable.Motivated by the idea of power function,a new non-linear strategy for decreasing inertia weight(DIW)was proposed based on the existing linear DIW.Then,a novel hierarchical multi-sensor data fusion algorithm adopting this strategy was presented,and the weight factor of the data fusion was estimated.The distinctive feature of this algorithm is its capability of fusing data in a near-optimal manner when there is no available information about the reliability of the information sources,the degree of redundancy/complementarities of the information sources,and the structure of the hierarchy.It obtained effective information from the fusion data,successfully removed the noise disturbance,and achieved favorable results. 展开更多
关键词 IOT data fusion extension theory particle swarm optimization decreasing inertia weight IPSO-ENN
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Meningioma of the Optical Nerves in a Case at the Hospitalier Center of Saint Denis in Ile de France
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作者 Adama Dembele Moro Sidibe +17 位作者 Ibrahim Conaré Mamadou Kolé Sidibé Larcheveque Florence Seror Julien Abdoulaye Napo Daouda Goita Oumar Diallo Djonny Jonas Dembele Mamadou Adama Togo Kadiatou Ba Koita Abdoulaye Nouhoum Coulibaly Cheick Fantamady Tounkara Nouhoum Touré Abdoulaye Konaté Jeannette Traore Sanoussi Bamani Lamine Traoré Japhet Popanou Théra 《Open Journal of Ophthalmology》 2023年第1期23-29,共7页
Summary: Optic nerve tumors are rare tumors, representing 3% - 5% of intracranial tumors developing mainly along the optic nerve and/or the chiasm. Optic nerve meningiomas are histologically benign tumors whose severi... Summary: Optic nerve tumors are rare tumors, representing 3% - 5% of intracranial tumors developing mainly along the optic nerve and/or the chiasm. Optic nerve meningiomas are histologically benign tumors whose severity is linked to diagnostic and especially therapeutic difficulties. The Optic nerve meningioma is the second leading cause of optic nerve tumor after glioma. Observation: We report the case of a 49-year-old woman from South Asia, who consults an ophthalmology department for progressive visual loss in her right eye for about a year with her glasses and would like to renew her optical correction. Having no particular medical history apart from left unilateral blindness is known for approximately 15 years. Magnetic Resonance Imaging (IRM) cerebral found a tissue mass with a clear outline and polylobules on the left temporo-peduncular. Through this case, we describe the circumstances of discovery of the disease, the clinical characteristics, as well as our diagnostic approach. Conclusion: In the majority of cases, these are benign tumours, the circumstances of which are discovered in multiple ways. A mostly unilateral and non-improvable loss of visual acuity must attract our attention. Renewing glasses may be the reason for discovering the disease. Today Magnetic Resonance Imaging (IRM) remains an important and capital examination for the diagnosis and monitoring of this pathology. 展开更多
关键词 MENINGIOMA Optic Nerve Decreased Visual Acuity IRM
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Optimal control of wireless energy transfer system via decreasing frequency 被引量:2
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作者 谭林林 黄学良 +1 位作者 周亚龙 赵俊峰 《Journal of Southeast University(English Edition)》 EI CAS 2013年第3期259-263,共5页
In order to solve the multiple power extreme value point problem caused by system frequency splitting during wireless energy transmission at short distances a transmission model of the system is established.With the c... In order to solve the multiple power extreme value point problem caused by system frequency splitting during wireless energy transmission at short distances a transmission model of the system is established.With the comprehensive consideration of the resonance frequency load parameters and the coupling between coils the internal factors of frequency splitting and boundary conditions are discussed.The results show that under the condition of the fixed load the higher the natural resonance frequency the easier the frequency splitting. As the frequency splitting occurs the frequency of the maximum power transfer is no longer with the natural resonance frequency which can make the system unstable and the transfer power more difficult to control. Therefore a decreasing-frequency method is proposed to avoid the system frequency splitting. And decreasing the system resonance frequency can make the system successfully withdraw the frequency splitting area at a short-distance range.Under the fixed load condition the transmission power of the system can be increased by 400% and the transmission efficiency is reduced by only 14% which greatly improves the transmission performance of the system. 展开更多
关键词 optimal control wireless energy transfer decreasing frequency
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一种自负载降速率包列可用带宽测量算法 被引量:1
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作者 张大陆 胡治国 +1 位作者 朱安奇 张俊生 《软件学报》 EI CSCD 北大核心 2012年第2期335-351,共17页
基于自负载周期流技术,提出一种采用降速率包列的可用带宽测量方法SLDRT(self-loading decreasing rate train),并全面分析了该算法在多跳网络、突发性背景流的环境下的性能.SLDRT采用单条包列即可实现对可用带宽的高速测量,具备单次采... 基于自负载周期流技术,提出一种采用降速率包列的可用带宽测量方法SLDRT(self-loading decreasing rate train),并全面分析了该算法在多跳网络、突发性背景流的环境下的性能.SLDRT采用单条包列即可实现对可用带宽的高速测量,具备单次采样、准确测量的特性,可通过调整递减因子等参数,提高测量精度,降低测量负载.理论分析和不同背景流场景下的实验结果表明:在多跳、突发性背景流下,SLDRT具有较强的健壮性;与pathChirp,Pathload算法相比,不仅测量精度优良,而且大量缩短了测量时间,减轻了因测量而引入的额外负载. 展开更多
关键词 网络测量 可用带宽 多跳路径 突发背景流 SLDRT(self-loading DECREASING RATE train)
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Long-term albumin infusion improves survival in patients with cirrhosis and ascites: An unblinded randomized trial 被引量:25
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作者 Roberto Giulio Romanelli Giorgio La Villa +8 位作者 Giuseppe Barletta Francesco Vizzutti Fabio Lanini Umberto Arena Vieri Boddi Roberto Tarquini Pietro Pantaleo Paolo Gentilini Giacomo Laffi 《World Journal of Gastroenterology》 SCIE CAS CSCD 2006年第9期1403-1407,共5页
AIM: To investigate the effects of long-term albumin administration on survival, recurrence of ascites and onset of other complications. METHODS: One hundred consecutive patients admitted for first-onset ascites wer... AIM: To investigate the effects of long-term albumin administration on survival, recurrence of ascites and onset of other complications. METHODS: One hundred consecutive patients admitted for first-onset ascites were randomized to receive diuretics plus human albumin 25 g/wk in the first year and 25 g every two wk thereafter (group 1) or diuretics alone (group 2). The primary endpoint was survival without liver transplantation. Secondary endpoints were recurrence of ascites and occurrence of other complications. RESULTS: Median follow-up was 84 (2-120) mo. Albu- min-treated patients had significantly greater cumulative survival rate (Breslow test= 7.05, P= 0.0078) and lower probability of ascites recurrence (51% versus 94%, P〈0.0001). Chronic albumin infusion resulted in a mean increase in survival of 16 mo. CONCLUSION: Long-term albumin administration after first-onset ascites significantly improves patients' survival and decreases the risk of ascites recurrence. 展开更多
关键词 Long-term albumin administration after first-onset ascites significantly improves patients' survival and decreases the risk of ascites recurrence.
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Improved hybrid iterative optimization method for seismic full waveform inversion
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作者 王义 董良国 刘玉柱 《Applied Geophysics》 SCIE CSCD 2013年第3期265-277,357,358,共15页
In full waveform inversion (FWI), Hessian information of the misfit function is of vital importance for accelerating the convergence of the inversion; however, it usually is not feasible to directly calculate the He... In full waveform inversion (FWI), Hessian information of the misfit function is of vital importance for accelerating the convergence of the inversion; however, it usually is not feasible to directly calculate the Hessian matrix and its inverse. Although the limited memory Broyden-Fletcher-Goldfarb-Shanno (L-BFGS) or Hessian-free inexact Newton (HFN) methods are able to use approximate Hessian information, the information they collect is limited. The two methods can be interlaced because they are able to provide Hessian information for each other; however, the performance of the hybrid iterative method is dependent on the effective switch between the two methods. We have designed a new scheme to realize the dynamic switch between the two methods based on the decrease ratio (DR) of the misfit function (objective function), and we propose a modified hybrid iterative optimization method. In the new scheme, we compare the DR of the two methods for a given computational cost, and choose the method with a faster DR. Using these steps, the modified method always implements the most efficient method. The results of Marmousi and overthrust model testings indicate that the convergence with our modified method is significantly faster than that in the L-BFGS method with no loss of inversion quality. Moreover, our modified outperforms the enriched method by a little speedup of the convergence. It also exhibits better efficiency than the HFN method. 展开更多
关键词 Full waveform inversion Hessian information limited memory BFGS method Hessian-free inexact Newton method decrease ratio
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NUMERICAL SIMULATION STUDY ON WUQING GEOTHERMAL RESERVOIR,TIANJIN
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作者 李新国 赵军 《Transactions of Tianjin University》 EI CAS 2001年第3期197-201,共5页
In this paper the computer code of AUTOUGH2 is used to carry out numerical simulation study on the Wuqing geothermal reservoir for evaluating reservoir performance upon different exploitation schemes.The simulating ca... In this paper the computer code of AUTOUGH2 is used to carry out numerical simulation study on the Wuqing geothermal reservoir for evaluating reservoir performance upon different exploitation schemes.The simulating calculation and analysis of two main cases,production without reinjection and production with reinjection,were carried out to illuminate and compare the temperature and pressure profiles with distance and time.The water level or pressure will decrease with the time of production,and the reinjection will cause the cooling effect of reinjection on the production zone. 展开更多
关键词 numerical simulation AUTOUGH2 RESERVOIR water level decrease pressure decrease REINJECTION cooling effect
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Indicative Significance of ENSO for Summer Precipitation in Liaoning Province
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作者 王大钧 徐智鑫 胡春丽 《Meteorological and Environmental Research》 CAS 2010年第8期102-104,共3页
Based on the summer precipitation data from 53 stations in Liaoning Province and sea surface temperature(SST) data of Hadley Center in 1961-2009,the decadal variation of the relationship between summer precipitation a... Based on the summer precipitation data from 53 stations in Liaoning Province and sea surface temperature(SST) data of Hadley Center in 1961-2009,the decadal variation of the relationship between summer precipitation and SST over Nino3 oceanic regions in the previous autumn was studied.The results showed that their correlation was decreased obviously in recent 30 years.In 1961-1974,summer rainfall could be forecasted according to the SST anomaly over Nino3 oceanic regions in the previous autumn,and there were above 25 stations with the sign accuracy of over 66.7%.However,there were only five stations with the same accuracy during 1980-2009.From 1961 to 1974,25 stations showed block distribution in the central and northeastern Liaoning,but the distribution of five stations was spotty in 1980-2009.Before the middle and latter half of the 1970s,Liaoning had more(less) summer rainfall when SST over the equatorial central and eastern Pacific was higher(lower) in the previous autumn.However,it was difficult to build indicative relationship above since 1980s. 展开更多
关键词 ENSO Summer precipitation DECREASE China
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Tillage Effect and Development Prospect of Fenlong Farming Tools with"Drill"
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作者 Benhui WEI 《Asian Agricultural Research》 2020年第6期27-34,38,共9页
In this paper,farming and crop cultivation effects of farming tools with"drill"which are invented independently in China are clarified firstly,containing horizontal cutting of soil,super deep ploughing,deep ... In this paper,farming and crop cultivation effects of farming tools with"drill"which are invented independently in China are clarified firstly,containing horizontal cutting of soil,super deep ploughing,deep loosening and not disturbing soil layer,granular soil,soil not easy to bond and harden,and one-time land preparation.It is a significant path to deeply develop and use the"five natural resources"not fully utilized by human beings(soil resources at plough bottom and below,saline-alkali land,natural rainfall,solar energy,oxygen)and realize"mitigation"of five natural disasters(flood,drought,high temperature,low temperature and climate warming).In the past 10 years,the farming tools have been applied in 40 kinds of crops in 26 provinces of China.Compared with vertical breaking of soil by traditional"plow",the amount of loose soil,water storage and dissolved oxygen in cultivated land increased by more than one time,and yield increased by 10%-50%.They have been applied in transformation of saline-alkali land in 10 provinces,and yield increased by 30%-150%.After Fenlong treatment for 1 and 2 years,biomass of sugarcane increased by 68.9%and 50.1%respectively.Net photosynthetic rates of Gramineous crops were improved by 6.82%-11.94%,while net photosynthetic rates of Legume crops were improved by 20.32%-32.08%.After"spiral drill","vertical two-knife drill","vertical three-knife drill"and other hollow series of Fenlong farming toolss were invented newly.They were the most advanced farming tools with large soil discharge and small resistance,and could be equipped in large-,medium-and small-size modern Fenlong agricultural machinery as key technology,thereby setting up a new"standard stalk"for world agricultural reform and bringing benefit to mankind. 展开更多
关键词 Farming tools with"drill" "Drilling"farming Transformation of saline-alkali land "Five increases and five decreases" Increasing production and improving quality Fenlong technique
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Mountain Atmospherics
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作者 Kern E. Kenyon 《Natural Science》 2021年第6期208-210,共3页
The purpose of the work is to examine the effects of compressibility on air properties when a wind blows against a sloping mountain surface. Previous research of air compression effects include the low speed wing and ... The purpose of the work is to examine the effects of compressibility on air properties when a wind blows against a sloping mountain surface. Previous research of air compression effects include the low speed wing and the crests of surface gravity waves propagating in the </span><span style="font-family:Verdana;">wind. In both cases, an algebraic expression was obtained for the lift force. When wind </span><span style="font-family:Verdana;">blows </span><span style="font-family:Verdana;">across a mountain and the assumption is made that a boundary layer of compressed air </span><span style="font-family:Verdana;">forms and remains attached to the mountain, a physical-chemical theory predicts that the wind will have no shear and the pressure and density will decrease with increasing altitude at the same rate. Combining Bernoulli’s law along streamlines with the cross-stream force balance, pressure gradient equals centrifugal force, and the perfect gas law for air, is the model used here. 展开更多
关键词 Mountain Winds Compressed Air Upward decreases of Pressure and Density
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从熵的本质来探索时空理论
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作者 尹真 《赣南师范学院学报》 1989年第S3期71-75,共5页
本文提出了宇宙间存在着与熵增加原理相对应的熵减少原理,且用熵减少原理阐明了宇宙间导致能量散逸过程与能量集中过程是不可分割地联系着的。最后根根熵减少原理得出的负熵概念,进一步说明了人吃饭与获得负熵是辩证统一的。
关键词 the theory of time space a PRINCIPLE of DECREASING ENTROPY NEGATIVE ENTROPY ENERGY DISSIPATION ENERGY conentraion
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基于Mean Decrease Impurity改进XGBoost算法 被引量:2
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作者 杜俊杰 朱永忠 丁根宏 《信息技术》 2019年第9期1-4,共4页
针对XGBoost算法在处理高维数据集分类准确率和效率下降的情况,文中提出一种基于mean decrease impurity算法改进的XGBoost算法;并设计频数算法解决mean decrease impurity算法对特征重要度排名的随机性。实验结果表明,本方法预测效率... 针对XGBoost算法在处理高维数据集分类准确率和效率下降的情况,文中提出一种基于mean decrease impurity算法改进的XGBoost算法;并设计频数算法解决mean decrease impurity算法对特征重要度排名的随机性。实验结果表明,本方法预测效率以及准确率要优于未改进XGBoost算法,同时mean decrease impurity算法也优于基于方差算法。因此,文中所提出的分类方法具有更高的准确率和效率。 展开更多
关键词 XGBoost 高维数据 mean DECREASE IMPURITY 集成学习
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A Note on HilbertsIntegral Inequalities 被引量:50
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作者 杨必成 《Chinese Quarterly Journal of Mathematics》 CSCD 1998年第4期83-86, ,共4页
In this note,by introudcing a couple of parameters T,t and estimating the weight function effectively,Hilberts integral inequalities are well generalized. As applications,we give some new Hilbers type inequalities.
关键词 Hilberts integral inequality weight function decreasing function
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MdATG18a overexpression improves basal thermotolerance in transgenic apple by decreasing damage to chloroplasts 被引量:11
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作者 Liuqing Huo Xun Sun +7 位作者 Zijian Guo Xin Jia Runmin Che Yiming Sun Yanfei Zhu Ping Wang Xiaoqing Gong Fengwang Ma 《Horticulture Research》 SCIE 2020年第1期2418-2432,共15页
High temperature is an abiotic stress factor that threatens plant growth and development.Autophagy in response to heat stress involves the selective removal of heat-induced protein complexes.Previously,we showed that ... High temperature is an abiotic stress factor that threatens plant growth and development.Autophagy in response to heat stress involves the selective removal of heat-induced protein complexes.Previously,we showed that a crucial autophagy protein from apple,MdATG18a,has a positive effect on drought tolerance.In the present study,we treated transgenic apple(Malus domestica)plants overexpressing MdATG18a with high temperature and found that autophagy protected them from heat stress.Overexpression of MdATG18a in apple enhanced antioxidase activity and contributed to the production of increased beneficial antioxidants under heat stress.Transgenic apple plants exhibited higher photosynthetic capacity,as shown by the rate of CO_(2) assimilation,the maximum photochemical efficiency of photosystem II(PSII),the effective quantum yield,and the electron transport rates in photosystems I and II(PSI and PSII,respectively).We also detected elevated autophagic activity and reduced damage to chloroplasts in transgenic plants compared to WT plants.In addition,the transcriptional activities of several HSP genes were increased in transgenic apple plants.In summary,we propose that autophagy plays a critical role in basal thermotolerance in apple,primarily through a combination of enhanced antioxidant activity and reduced chloroplast damage. 展开更多
关键词 DAMAGE DECREASING protected
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