期刊文献+
共找到11,794篇文章
< 1 2 250 >
每页显示 20 50 100
Ultra-tight GPS/INS integration based long-range rocket projectile navigation method 被引量:4
1
作者 赵捍东 李志鹏 张会锁 《Journal of Measurement Science and Instrumentation》 CAS CSCD 2015年第2期153-160,共8页
Accurate navigation is important for long-range rocket projectile's precise striking. To obtain stable and high-per- formance navigation result, a ultra-tight global positioning system/inertial navigation system (GP... Accurate navigation is important for long-range rocket projectile's precise striking. To obtain stable and high-per- formance navigation result, a ultra-tight global positioning system/inertial navigation system (GPS/INS) integration based nav- igation approach is proposed. The accurate short-time output of INS is used by GPS receiver to assist in acquisition of signal, and output information of INS and GPS is fused based on federated filter. Meanwhile, the improved cubature Kalman filter with strong tracking ability is chosen to serve as the local filter, and then the federated filter is enhanced based on vector sharing theory. Finally, simulation results show that the navigation accuracy with the proposed method is higher than that with traditional methods. It provides reference for long-range rocket projectile navigation. 展开更多
关键词 long-range rocket projectile global position system inertial measuring unit ultra-tight integration
下载PDF
In- and Anti-transition of Firing Patterns Induced by Random Long-range Connections in Coupled Hindmarsh-Rose Neurons System 被引量:1
2
作者 王鹏 张季谦 任海林 《Chinese Journal of Chemical Physics》 SCIE CAS CSCD 2010年第1期23-29,I0001,共8页
The effects of random long-range connections (shortcuts) on the transitions of neural firing patterns in coupled Hindmarsh-Rose neurons are investigated, where each neuron is subjected to an external current. It is ... The effects of random long-range connections (shortcuts) on the transitions of neural firing patterns in coupled Hindmarsh-Rose neurons are investigated, where each neuron is subjected to an external current. It is found that, on one hand, the system can achieve the transition of neural firing patterns from the fewer-period state to the multi-period one, when the number of the added shortcuts in the neural network is greater than a threshold value, indicating the occurrence of in-transition of neural firing patterns. On the other hand, for a stronger coupling strength, we can also find the similar but reverse results by adding some proper random connections. In addition, the influences of system size and coupling strength on such transition behavior, as well as the internality between the transition degree of firing patterns and its critical characteristics for different external stimulation current, are also discussed. 展开更多
关键词 In- and anti-transition Random long-range connection Firing pattern System size
下载PDF
Ag、Cu、Au、Ni、Pd、Pt的Long-range Finis-Sinclair势构建及其二元合金形成焓的计算
3
作者 刘艳侠 顾慧 +2 位作者 刘磊 孙佳佳 高岩 《辽宁大学学报(自然科学版)》 CAS 2009年第3期193-196,共4页
构建了fcc金属Cu、Ag、Au、Ni、Pd、Pt的Long-range Finnis-Sinclair势,并利用晶格常数、体弹性模量和金属的内聚能的实验数据拟合了这几种金属的Long-range Finnis-Sinclair势参数;利用Miedema理论和所构建的原子间相互作用势计算了Cu,... 构建了fcc金属Cu、Ag、Au、Ni、Pd、Pt的Long-range Finnis-Sinclair势,并利用晶格常数、体弹性模量和金属的内聚能的实验数据拟合了这几种金属的Long-range Finnis-Sinclair势参数;利用Miedema理论和所构建的原子间相互作用势计算了Cu,Ag,Au,Ni,Pd,Pt的二元合金的形成焓.对两种计算结果进行了比较,并与已有的实验结果进行了比较.结果表明,使用Long-range Finnis-Sinclair势计算合金的形成焓能够得到令人满意的结果. 展开更多
关键词 long-range Finnis-Sinclair势 MIEDEMA理论 形成焓
下载PDF
Listening Barriers Among Chinese Students And Training Tactics 被引量:4
4
作者 任小萍 《延安教育学院学报》 2001年第2期39-41,47,共4页
Listening is very important in the learning of English language. Most of our Chinese students regard listening comprehension as the most difficult part among all kinds of examinations. So if we can find the reasons wh... Listening is very important in the learning of English language. Most of our Chinese students regard listening comprehension as the most difficult part among all kinds of examinations. So if we can find the reasons why the students exist such barriers that prevent them from understanding, and give them ways of training it, I’m sure it will help the students to improve their ability of language learning. 展开更多
关键词 英语教学 听力训练 听力障碍 语音基础知识 听力技巧 日常训练
下载PDF
SwinFusion: Cross-domain Long-range Learning for General Image Fusion via Swin Transformer 被引量:29
5
作者 Jiayi Ma Linfeng Tang +3 位作者 Fan Fan Jun Huang Xiaoguang Mei Yong Ma 《IEEE/CAA Journal of Automatica Sinica》 SCIE EI CSCD 2022年第7期1200-1217,共18页
This study proposes a novel general image fusion framework based on cross-domain long-range learning and Swin Transformer,termed as SwinFusion.On the one hand,an attention-guided cross-domain module is devised to achi... This study proposes a novel general image fusion framework based on cross-domain long-range learning and Swin Transformer,termed as SwinFusion.On the one hand,an attention-guided cross-domain module is devised to achieve sufficient integration of complementary information and global interaction.More specifically,the proposed method involves an intra-domain fusion unit based on self-attention and an interdomain fusion unit based on cross-attention,which mine and integrate long dependencies within the same domain and across domains.Through long-range dependency modeling,the network is able to fully implement domain-specific information extraction and cross-domain complementary information integration as well as maintaining the appropriate apparent intensity from a global perspective.In particular,we introduce the shifted windows mechanism into the self-attention and cross-attention,which allows our model to receive images with arbitrary sizes.On the other hand,the multi-scene image fusion problems are generalized to a unified framework with structure maintenance,detail preservation,and proper intensity control.Moreover,an elaborate loss function,consisting of SSIM loss,texture loss,and intensity loss,drives the network to preserve abundant texture details and structural information,as well as presenting optimal apparent intensity.Extensive experiments on both multi-modal image fusion and digital photography image fusion demonstrate the superiority of our SwinFusion compared to the state-of-theart unified image fusion algorithms and task-specific alternatives.Implementation code and pre-trained weights can be accessed at https://github.com/Linfeng-Tang/SwinFusion. 展开更多
关键词 Cross-domain long-range learning image fusion Swin transformer
下载PDF
Trend of Salt Lake Changes in the Background of Global Warming and Tactics for Adaptation to the Changes 被引量:12
6
作者 ZHENGMianping QIWen +2 位作者 JIANGXianfeng ZHAOYuanyi LIMinghui 《Acta Geologica Sinica(English Edition)》 SCIE CAS CSCD 2004年第3期795-807,共13页
Salt lakes are a mirror of climatic changes and provide holographic records of environmental changes of lakes. According to a study of geological hazards in typical salt lake areas in China and other regions, the auth... Salt lakes are a mirror of climatic changes and provide holographic records of environmental changes of lakes. According to a study of geological hazards in typical salt lake areas in China and other regions, the authors explain how geological hazards in salt lake areas are caused by natural agents and how humans can seek benefits, avoid hazards and reduce losses on the premise that they have monitored and mastered the trend of salt lake changes in advance and even can store flood and recharge water in lakes and extract saline resources. The climate in western China is probably turning from warm-dry to warm-moist. The authors analyze the change trend of salt lakes sensu lato (with salinity≥0.3 wt% (NaCl)eq) and salt lakes sensu stricto (with salinity ≥3.5 wt% (NaCl)eq) in China in such climatic conditions and distinguish three types of salt lake areas (i.e. lake water rising type, lake water falling type and lake water rising and unstable type) according to the characteristics of lake water rising and shrinking. In order to conform to the climatic and lake changes in China's salt lake areas, the authors propose to add and improve hydrological and meteorological observation stations and integrate observations with remote sensing monitoring in important salt lake areas and set up multidisciplinary and interdepartmental basic projects to monitor and study recent climatic and environmental changes in salt lake areas of western China. Moreover, it is necessary to build additional flood-control and drought-preventing water conservancy facilities in key salt lake areas and work out measures for ecological protection in salt lake areas. Full consideration should be given to the influence of flooding when building saltfields and implementing capital projects. 展开更多
关键词 global warming geological hazard of salt lake trend of salt lake change salt lake water rising and shrinking types tactics for adaptation to change
下载PDF
Long-range electron synergy over Pt_(1)-Co_(1)/CN bimetallic single-atom catalyst in enhancing charge separation for photocatalytic hydrogen production 被引量:4
7
作者 Man Yang Jing Mei +3 位作者 Yujing Ren Jie Cui Shuhua Liang Shaodong Sun 《Journal of Energy Chemistry》 SCIE EI CAS CSCD 2023年第6期502-509,I0011,共9页
The development of novel single-atom catalysts with optimal electron configuration and economical noble-metal cocatalyst for efficient photocatalytic hydrogen production is of great importance,but still challenging.He... The development of novel single-atom catalysts with optimal electron configuration and economical noble-metal cocatalyst for efficient photocatalytic hydrogen production is of great importance,but still challenging.Herein,we fabricate Pt and Co single-atom sites successively on polymeric carbon nitride(CN).In this Pt_(1)-Co_(1)/CN bimetallic single-atom catalyst,the noble-metal active sites are maximized,and the single-atomic Co_(1)N_4sites are tuned to Co_(1)N_3sites by photogenerated electrons arising from the introduced single-atomic Pt_(1)N_4sites.Mechanism studies and density functional theory(DFT)calculations reveal that the 3d orbitals of Co_(1)N_3single sites are filled with unpaired d-electrons,which lead to the improved visible-light response,carrier separation and charge migration for CN photocatalysts.Thereafter,the protons adsorption and activation are promoted.Taking this advantage of long-range electron synergy in bimetallic single atomic sites,the photocatalytic hydrogen evolution activity over Pt_(1)-Co_(1)/CN achieves 915.8 mmol g^(-1)Pt h^(-1),which is 19.8 times higher than Co_(1)/CN and 3.5 times higher to Pt_(1)/CN.While this electron-synergistic effect is not so efficient for Pt nanoclusters.These results demonstrate the synergistic effect at electron-level and provide electron-level guidance for the design of efficient photocatalysts. 展开更多
关键词 Bimetallic single-atom catalyst long-range electron synergy Charge separation/transfer Carbon nitride Hydrogen production
下载PDF
Super long-range diffusion of carbon during proeutectoid ferrite transformation 被引量:2
8
作者 ZHANG Suo-quan JIAO Si-hai +3 位作者 DING Jian-hua WAN Di LIU Zhen-yu WANG Guo-dong 《Journal of Central South University》 SCIE EI CAS CSCD 2019年第3期560-566,共7页
In order to explore the possible diffusion distance of carbon during proeutectoid ferrite transformation, a slow cooling test of low carbon steel was carried out under vacuum of the thermal simulator. The microstructu... In order to explore the possible diffusion distance of carbon during proeutectoid ferrite transformation, a slow cooling test of low carbon steel was carried out under vacuum of the thermal simulator. The microstructure and thermal expansion curve were discussed and the carbon concentration inside the sample was measured. The ferrite layer of about 450 μm thickness was obtained without pearlite on the surface of the sample in the microstructure. The thermal expansion curve shows that the ferrite layer without pearlite is formed during the local phase transformation, which is followed by the global transformation. The carbon concentration in the core of the sample (0.061%) is significantly higher than that of the bulk material (0.054%). All results show that carbon has long-range diffusion from the outer layer to the inner layer of the sample. The transformation is predominantly interface-controlled mode during local transformation, and the interface migration rate is about 2.25 μm/s. 展开更多
关键词 low carbon steel local transformation super long-rang diffusion interface-controlled mode
下载PDF
Are“Internet+”tactics the key to poverty alleviation in China’s rural ethnic minority areas? Empirical evidence from Sichuan Province 被引量:4
9
作者 Xiang Yin Zhiyi Meng +2 位作者 Xin Yi Yong Wang Xia Hua 《Financial Innovation》 2021年第1期635-653,共19页
China has made great efforts to alleviate poverty in rural ethnic minority areas and targeted achieving the poverty-alleviation task by the end of 2020.Aba,Ganzi,and Liangshan,three of the poorest ethnic prefectures i... China has made great efforts to alleviate poverty in rural ethnic minority areas and targeted achieving the poverty-alleviation task by the end of 2020.Aba,Ganzi,and Liangshan,three of the poorest ethnic prefectures in Sichuan Province,Southwest China,have all implemented“Internet+”tactics since 2013,which have had the positive effect of increasing family revenues by improving communication infrastructure and encouraging the large-scale use of e-commerce.This paper aims to comprehensively investigate whether“Internet+”tactics play a key role in poverty alleviation in Sichuan’s rural ethnic minority areas and to propose further measures to enhance the efficiency of e-commerce practice.To this end,we conduct an analysis using the framework of classic growth theory and use panel data from 2000 to 2018 to examine the relationship between Communication Infrastructure Investment(CII)and a set of poverty-alleviation indicators,including local GDP growth rate(LGGR),local government revenue(LGR),and per-capita income of residents(PCIR).The results indicate that strengthening CII improves the PCIR and local economic growth,playing a key role in poverty alleviation.However,the stimulation of CII on LGGR and LGR wanes as time passes.More financial and technical actions will be needed to improve the efficiency and quality of current strategies for sustainable development in those areas. 展开更多
关键词 Poverty alleviation “Internet+”tactics Rural ethnic minority areas Empirical analysis
下载PDF
The influence of magnetic field on the beam quality of relativistic electron beam long-range propagation in near-Earth environment 被引量:2
10
作者 Jianhong HAO Xi WANG +4 位作者 Fang ZHANG Qiang ZHAO Jieqing FAN Bixi XUE Zhiwei DONG 《Plasma Science and Technology》 SCIE EI CAS CSCD 2021年第11期42-49,共8页
In recent years,it has been proposed to use satellite-mounted radio-frequency(RF)accelerators to produce high-current relativistic electron beams to complete debris removal tasks.However,when simulating the long-range... In recent years,it has been proposed to use satellite-mounted radio-frequency(RF)accelerators to produce high-current relativistic electron beams to complete debris removal tasks.However,when simulating the long-range propagation(km-range)process of the electron beam,it is difficult to directly use the particle-in-cell method to simultaneously consider the space charge effect of beam and the influence of the geomagnetic field.Owing to these limitations,in this paper,we proposed a simplified method.The ps-range electronic micropulses emitted by the RF accelerator were transmitted and fused to form a ns-range electron beam;then,combined with the improved moving window technology,the model was constructed to simulate the long-range propagation process of the relativistic electron beam in near-Earth environment.Finally,by setting the direction of movement of the beam to be parallel,perpendicular and at an inclination of 3°to the magnetic field,we analyzed and compared the effects of the applied magnetic fields in different directions on the quality of the beam during long-range propagation.The simulation results showed that the parallel state of the beam motion and magnetic fields should be achieved as much as possible to ensure the feasibility of the space debris removal. 展开更多
关键词 space debris relativistic electron beam long-range propagation geomagnetic field radio frequency accelerator
下载PDF
Self-sustained target waves in excitable media with only a long-range link 被引量:1
11
作者 钱郁 王参军 +2 位作者 石虎山 弭元元 黄晓东 《Chinese Physics B》 SCIE EI CAS CSCD 2011年第10期457-462,共6页
In this paper we investigate spatiotemporal pattern formation in excitable media with only a long-range link. Besides the trivial solutions of spiral patterns, we find the asymptotic self-sustained target waves in the... In this paper we investigate spatiotemporal pattern formation in excitable media with only a long-range link. Besides the trivial solutions of spiral patterns, we find the asymptotic self-sustained target waves in the autonomous tissues. The wave source supporting this kind of new pattern is the oscillatory one-dimensional Winfree-loop self- organized under the presence of a long-range link, which is explored by the dominant phase-advanced driving method. Based on this understanding we can effectively regulate the oscillations of excitable media by suitably arranging the long-range link, including construction of self-sustained target waves with controllable period and wave length, or manipulation of system states between different patterns. 展开更多
关键词 self-sustained target waves long-range link one-dimensional Winfree-loop
下载PDF
Preliminary research on the relationship between long-range correlations and predictability 被引量:1
12
作者 张志森 龚志强 +2 位作者 支蓉 封国林 胡经国 《Chinese Physics B》 SCIE EI CAS CSCD 2011年第1期23-32,共10页
By establishing the Markov model for a long-range correlated time series (LRCS) and analysing its evolutionary characteristics, this paper defines a physical effective correlation length (ECL) T, which reflects th... By establishing the Markov model for a long-range correlated time series (LRCS) and analysing its evolutionary characteristics, this paper defines a physical effective correlation length (ECL) T, which reflects the predictability of the LRCS. It also finds that the ECL has a better power law relation with the long-range correlated exponent γ of the LRCS: T = Kexp(-γ/0.3) + Y, (0 〈 γ〈 1) the predictability of the LRCS decays exponentially with the increase of γ It is then applied to a daily maximum temperature series (DMTS) recorded at 740 stations in China between the years 1960-2005 and calculates the ECL of the DMTS. The results show the remarkable regional distributive feature that the ECL is about 10-14 days in west, northwest and northern China, and about 5-10 days in east, southeast and southern China. Namely, the predictability of the DMTS is higher in central-west China than in east and southeast China. In addition, the ECL is reduced by 1-8 days in most areas of China after subtracting the seasonal oscillation signal of the DMTS from its original DMTS; however, it is only slightly altered when the decadal linear trend is removed from the original DMTS. Therefore, it is shown that seasonal oscillation is a significant component of daily maximum temperature evolution and may provide a basis for predicting daily maximum temperatures. Seasonal oscillation is also significant for guiding general weather predictions, as well as seasonal weather predictions. 展开更多
关键词 long-range correlation information entropy effective correlation length PREDICTABILITY
下载PDF
THE VLASOV-POISSON-BOLTZMANN SYSTEM NEAR MAXWELLIANS FOR LONG-RANGE INTERACTIONS 被引量:1
13
作者 王路生 肖清华 +1 位作者 熊林杰 赵会江 《Acta Mathematica Scientia》 SCIE CSCD 2016年第4期1049-1097,共49页
In this article, we are concerned with the construction of global smooth small-amplitude solutions to the Cauchy problem of the one species Vlasov-Poisson-Boltzmann system near Maxwellians for long-range interactions.... In this article, we are concerned with the construction of global smooth small-amplitude solutions to the Cauchy problem of the one species Vlasov-Poisson-Boltzmann system near Maxwellians for long-range interactions. Compared with the former result obtained by Duan and Liu in [12] for the two species model, we do not ask the initial perturbation to satisfy the neutral condition and our result covers all physical collision kernels for the full range of intermolecular repulsive potentials. 展开更多
关键词 One-species Vlasov-Poisson-Boltzmann system long-range interactions global solutions near Maxwellians time-velocity weighted energy method
下载PDF
A Long-Range Generalized Predictive Control Algorithm for a DFIG Based Wind Energy System 被引量:1
14
作者 J.S.Solis-Chaves Lucas L.Rodrigues +1 位作者 C.M.Rocha-Osorio Alfeu J.Sguarezi Filho 《IEEE/CAA Journal of Automatica Sinica》 SCIE EI CSCD 2019年第5期1209-1219,共11页
This paper presents a new Long-range generalized predictive controller in the synchronous reference frame for a wind energy system doubly-fed induction generator based. This controller uses the state space equations t... This paper presents a new Long-range generalized predictive controller in the synchronous reference frame for a wind energy system doubly-fed induction generator based. This controller uses the state space equations that consider the rotor current and voltage as state and control variables, to execute the predictive control action. Therefore, the model of the plant must be transformed into two discrete transference functions, by means of an auto-regressive moving average model, in order to attain a discrete and decoupled controller, which makes it possible to treat it as two independent single-input single-output systems instead of a magnetic coupled multiple-input multiple-output system. For achieving that, a direct power control strategy is used, based on the past and future rotor currents and voltages estimation. The algorithm evaluates the rotor current predictors for a defined prediction horizon and computes the new rotor voltages that must be injected to controlling the stator active and reactive powers. To evaluate the controller performance, some simulations were made using Matlab/Simulink. Experimental tests were carried out with a small-scale prototype assuming normal operating conditions with constant and variable wind speed profiles. Finally, some conclusions respect to the dynamic performance of this new controller are summarized. 展开更多
关键词 Direct power CONTROL DOUBLY-FED INDUCTION generator flux oriented CONTROL generalized PREDICTIVE CONTROL long-range PREDICTIVE CONTROL wind energy systems
下载PDF
Exploring Listening Comprehension Tactics and Interaction Patterns
15
作者 常红梅 《阴山学刊》 2004年第6期119-123,共5页
Examining specific tactics is useful in language teaching.Cognitive strategies identified in the literature include elaboration,prediction,contextualization and visualization;Metacognitive strategies identified includ... Examining specific tactics is useful in language teaching.Cognitive strategies identified in the literature include elaboration,prediction,contextualization and visualization;Metacognitive strategies identified include self-monitoring,selective attention,directed attention,self-evaluation and so on.In the comparison of the two learners’ listening results,it was found that although they used many similar tactics,the higher ability learner demonstrated more effective use of both cognitive and metacognitive tactics. 展开更多
关键词 LISTENING COMPREHENSION COGNITIVE tactics matacognitive tactics interaction
下载PDF
Analysis of Long-Range Transmission Loss in the West Pacific Ocean 被引量:1
16
作者 吴丽丽 彭朝晖 《Chinese Physics Letters》 SCIE CAS CSCD 2015年第9期74-78,共5页
A long-range sound propagation experiment was conducted in the West Pacific Ocean in July 2013. Linear frequency-modulated signals with a frequency band of 260-360Hz were transmitted by a transducer hung on a floating... A long-range sound propagation experiment was conducted in the West Pacific Ocean in July 2013. Linear frequency-modulated signals with a frequency band of 260-360Hz were transmitted by a transducer hung on a floating ship during the experiment and were received by a horizontal line array towed by another ship sailing away from the transducer. The maximum distance between the two ships was 1029km. Signals were received at the distances 34-220 kin, 612-635 km and 926-1029 kin. Transmission loss versus distance between source and receiver was obtained and compared with the theoretical results predicted by the parabolic equation method program RAM. It is shown that RAM is adequate for estimating the transmission loss for distances up to 1029km. When the water depth is larger than the surface conjugate depth, the ocean bottom rarely influences the transmission loss in the convergence zones. However, in the opposite situation, the ocean bottom contributes significantly to the transmission loss. 展开更多
关键词 Analysis of long-range Transmission Loss in the West Pacific Ocean
下载PDF
Tactics for Reading Comprehension
17
作者 孔祥航 张艳荣 《辽宁省交通高等专科学校学报》 2003年第4期63-64,66,共3页
In recent years, reading comprehension is taking up a larger and larger part in almost every international test or domestic examination. Knowing the basic knowledge and grasping the test - taking tactics are key facto... In recent years, reading comprehension is taking up a larger and larger part in almost every international test or domestic examination. Knowing the basic knowledge and grasping the test - taking tactics are key factors of good reading comprehension. In this thesis, I will dwell on nine commonly used tactics for reading comprehension. This will help you to deal with the problems with reading comprehension efficiently. 展开更多
关键词 阅读理解 高等教育 英语教学 主题句 阅读练习 英语考试
下载PDF
Control tactics of poplar diseases in China
18
作者 项存悌 朱虹 《Journal of Forestry Research》 SCIE CAS CSCD 2000年第4期252-254,共3页
Based on the present studies and literatures about the poplar diseases in China, the present study situation of poplar disease was introduced in this paper. 31 kinds of poplar diseases were collected of which there we... Based on the present studies and literatures about the poplar diseases in China, the present study situation of poplar disease was introduced in this paper. 31 kinds of poplar diseases were collected of which there were 14 kinds of leaves disease, 11 kinds of branch disease, 4 kinds of root disease, 2 kinds of stand rot. Each poplar species was studied on the harm, distribution, symptom, pathogens, occurrence regulation and control measures. According to previously studies, the sustained control tactics of poplar disease were summarized in this paper. 展开更多
关键词 Poplar diseases SYMPTOM Present situation Control tactics
下载PDF
On-line current feed and computer aided control tactics for automatic balancing head
19
作者 李勇 陆永平 +1 位作者 须根发 夏松波 《Journal of Harbin Institute of Technology(New Series)》 EI CAS 2002年第2期205-207,共3页
In the designed automatic balancing head, a non contact induction transformer is used to deliver driving energy to solve the problem of current fed and controlling on line. Computer controlled automatic balancing expe... In the designed automatic balancing head, a non contact induction transformer is used to deliver driving energy to solve the problem of current fed and controlling on line. Computer controlled automatic balancing experiments with phase magnitude control tactics were performed on a flexible rotor system. Results of the experiments prove that the energy feeding method and the control tactics are effective in the automatic balancing head for vibration controlling. 展开更多
关键词 AUTOMATIC balancing balancing HEAD ON-LINE CONTROL tactics
下载PDF
Review of runoff forestry in Shanxi Province and sustainable development tactics of forestry
20
作者 张新波 邝立刚 任建茹 《Journal of Forestry Research》 CAS CSCD 2000年第2期135-139,共5页
Through more than one month of investigation on runoff forestry in Luliang mountainous areas of Shanxi Province, the runoff forestry techniques were regarded as having a popularized value in arid and semi-arid areas. ... Through more than one month of investigation on runoff forestry in Luliang mountainous areas of Shanxi Province, the runoff forestry techniques were regarded as having a popularized value in arid and semi-arid areas. The development of runoff forestry in Shanxi Province was summarized and the sustainable development tactics was put forward. 展开更多
关键词 Semi-arid areas Runoff forestry Sustainable development Development tactics
下载PDF
上一页 1 2 250 下一页 到第
使用帮助 返回顶部