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Characteristics of long-distance mobile mRNAs from shoot to root in grafted plant species
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作者 Mengmeng Fu Zhen Xu +7 位作者 Huaying Ma Yifan Hao Ji Tian Yi Wang Xinzhong Zhang Xuefeng Xu Zhenhai Han Ting Wu 《Horticultural Plant Journal》 SCIE CAS CSCD 2024年第1期25-37,共13页
Thousands of long-distance mobile mRNAs were identified from different grafting systems,based on high-throughput sequencing technology.Moreover,the long-distance delivery of RNAs was proved to involve multiple mechani... Thousands of long-distance mobile mRNAs were identified from different grafting systems,based on high-throughput sequencing technology.Moreover,the long-distance delivery of RNAs was proved to involve multiple mechanisms.Here,we analyzed the homology,motif,and tRNA-like structure(TLS)of long-distance mobile mRNAs identified by RNA-seq as well as the RNA-binding protein(RBP)in nine grafting combinations including Arabidopsis thaliana,Vitis vinifera,Cucumis sativus,Citrullus lanatus,Nicotiana benthamiana,Malus domestica,Pyrus spp.,Glycine max and Phaseolus vulgaris.Although several mRNAs were found to be shared in herbaceous,woody,and related species,the vast majority of long-distance mobile mRNAs were species-specific.Four non-specific movement-related motifs were identified,while the TLS was not necessary for mRNA long distance mobility.In addition,we found that RBPs were conserved among herbaceous and woody plants as well as related species.This paper reports a further in-depth analysis of the endogenous mechanisms by which the species-specific transportable m RNAs were selected by bioinformatics,in order to provide insights for future research on long-distance mobile mRNAs. 展开更多
关键词 Grafting combination long-distance mobile mRNA TLS RNA binding proteins
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Magnetic Field Emulations of Small Inhibitor RNA: Effects on Implanted GL261 Tumors in C57BL/6 Immune Competent Mice
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作者 Xavier A. Figueroa Gabriel Vogeli B. Michael Butters 《Open Journal of Biophysics》 2024年第4期339-354,共16页
EMulate Therapeutics has developed a system for emulating the effects of solvated molecules via their magnetic field recordings. Recordings of magnetic field emissions of select small inhibitor RNAs (siRNAs;murine tar... EMulate Therapeutics has developed a system for emulating the effects of solvated molecules via their magnetic field recordings. Recordings of magnetic field emissions of select small inhibitor RNAs (siRNAs;murine targeting CTLA-4 and murine targeting PD-1) were tested on C57Bl/6 mice implanted subcutaneously with the GL261 murine tumor cell line. A signal composed of concatenated recordings of siRNA molecules targeting the murine CTLA-4 and PD-1 receptors (labeled A2) was used in immune competent C57Bl/6 mice. The mice were flank implanted with the murine glioblastoma cell line GL261. Mice were exposed to the signal continuously (24 hours a day) until tumor volumes reached the designated volume limit. Tumors were excised and analyzed via PAGE/Western blot for the expression of CTLA-4, PD-1, Ki67, Caspase 3, CD4 and CD8. Terminal blood draws were used for CBCs. We report the down regulation of the checkpoint inhibitors CTLA-4 in the exposed mice. Significant tumor volume reduction was observed in mice exposed to the siRNA signal compared to control mice;no adverse events were recorded. Cell blood counts (CBC) and protein expression patterns were observed to correlate with the expected function of protein expression inhibition of the targets. 展开更多
关键词 Cytotoxic T-Lymphocyte Antigen 4 (CTLA-4) Programmed Cell Death Protein 1 (PD-1) Electromagnetic Field emulation Cancer Tumor Murine Glioblastoma Multiforme (GBM)
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Water hammer protection for diversion systems in front of pumps in long-distance water supply projects 被引量:4
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作者 Lin Shi Jian Zhang +3 位作者 Xiao-dong Yu Sheng Chen Wen-long Zhao Xu-yun Chen 《Water Science and Engineering》 EI CAS CSCD 2023年第2期211-218,共8页
For a water supply system with long-distance diversion pipelines, in addition to the water hammer problems that occur beyond pumps, the safety of the water diversion pipeline in front of pumps also deserves attention.... For a water supply system with long-distance diversion pipelines, in addition to the water hammer problems that occur beyond pumps, the safety of the water diversion pipeline in front of pumps also deserves attention. In this study, a water hammer protection scheme combined with an overflow surge tank and a regulating valve was developed. A mathematical model of the overflow surge tank was developed, and an analytical formula for the height of the overflow surge tank was derived. Furthermore, a practical water supply project was used to evaluate the feasibility of the combined protection scheme and analyze the sensitivity of valve regulation rules. The results showed that the combined protection scheme effectively reduced the height of the surge tank, lessened the difficulties related to construction, and reduced the necessary financial investment for the project. The two-stage closing rule articulated as fast first and then slow could minimize the overflow volume of the surge tank when the power failure occurred, while the two-stage opening rule articulated as slow first and then fast could be more conducive to the safety of the water supply system when the pump started up. 展开更多
关键词 long-distance diversion pipeline Water supply Water hammer Overflow surge tank Regulating valve
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On Dynamic Channel Emulation in Sector MPAC for Over-the-Air Testing of Beamformed Massive MIMO Devices 被引量:1
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作者 Xiaochen Chen Heng Wang +2 位作者 Weimin Wang Zheng Liu Yuanan Liu 《China Communications》 SCIE CSCD 2023年第4期41-56,共16页
In this article,novel emulation strategies for the sectored multiple probe anechoic chamber(SMPAC)are proposed to enable the reliable evaluation of the massive multiple-input multiple-output(MIMO)device operating at b... In this article,novel emulation strategies for the sectored multiple probe anechoic chamber(SMPAC)are proposed to enable the reliable evaluation of the massive multiple-input multiple-output(MIMO)device operating at beamforming mode,which requires a realistic non-stationary channel environment.For the dynamic propagation emulation,an efficient closed-form probe weighting strategy minimizing the power angular spectrum(PAS)emulation errors is derived,substantially reducing the associated computational complexity.On the other hand,a novel probe selection algorithm is proposed to reproduce a more accurate fading environment.Various standard channel models and setup configurations are comprehensively simulated to validate the capacity of the proposed methods.The simulation results show that more competent active probes are selected with the proposed method compared to the conventional algorithms.Furthermore,the derived closedform probe weighting strategy offers identical accuracy to that obtained with complicated numerical optimization.Moreover,a realistic dynamic channel measured in an indoor environment is reconstructed with the developed methodologies,and 95.6%PAS similarity can be achieved with 6 active probes.The satisfactory results demonstrate that the proposed algorithms are suitable for arbitrary channel emulation. 展开更多
关键词 BEAMFORMING channel emulation massive MIMO device multiple probe anechoic chamber(MPAC) over-the-air testing
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Adaptive Emulation Framework for Multi-Architecture IoT Firmware Testing
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作者 Jihyeon Yu Juhwan Kim +2 位作者 Youngwoo Lee Fayozbek Rustamov Joobeom Yun 《Computers, Materials & Continua》 SCIE EI 2023年第5期3291-3315,共25页
Internet of things(IoT)devices are being increasingly used in numerous areas.However,the low priority on security and various IoT types have made these devices vulnerable to attacks.To prevent this,recent studies have... Internet of things(IoT)devices are being increasingly used in numerous areas.However,the low priority on security and various IoT types have made these devices vulnerable to attacks.To prevent this,recent studies have analyzed firmware in an emulation environment that does not require actual devices and is efficient for repeated experiments.However,these studies focused only on major firmware architectures and rarely considered exotic firmware.In addition,because of the diversity of firmware,the emulation success rate is not high in terms of large-scale analyses.In this study,we propose the adaptive emulation framework for multi-architecture(AEMA).In the field of automated emulation frameworks for IoT firmware testing,AEMA considers the following issues:(1)limited compatibility for exotic firmware architectures,(2)emulation instability when configuring an automated environment,and(3)shallow testing range resulting from structured inputs.To tackle these problems,AEMAcan emulate not onlymajor firmware architectures but also exotic firmware architectures not previously considered,such as Xtensa,ColdFire,and reduced instruction set computer(RISC)version five,by implementing a minority emulator.Moreover,we applied the emulation arbitration technique and input keyword extraction technique for emulation stability and efficient test case generation.We compared AEMA with other existing frameworks in terms of emulation success rates and fuzz testing.As a result,AEMA succeeded in emulating 864 out of 1,083 overall experimental firmware and detected vulnerabilities at least twice as fast as the experimental group.Furthermore,AEMAfound a 0-day vulnerability in realworld IoT devices within 24 h. 展开更多
关键词 Internet of things(IoT) emulation framework FIRMWARE FUZZING concolic execution vulnerability
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基于UART Emulation技术的MVB网卡设计与组网研究
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作者 王峰超 刘泰 赵冬玉 《机车电传动》 北大核心 2015年第1期43-46,50,共5页
提出一种MVB网卡设计方案,在主机与MVB控制器的架构上结合UART Emulation技术,较为完善地实现了MVB设备的过程数据、消息数据、用户编程等功能。利用所设计的网卡与其他MVB网络设备进行MVB组网研究,依据单调比率算法进行周期扫描表的设... 提出一种MVB网卡设计方案,在主机与MVB控制器的架构上结合UART Emulation技术,较为完善地实现了MVB设备的过程数据、消息数据、用户编程等功能。利用所设计的网卡与其他MVB网络设备进行MVB组网研究,依据单调比率算法进行周期扫描表的设计,在所搭建的网络平台上进行基本的通信测试,验证了设计的正确性和可行性。该网卡尺寸符合标准3U大小,便于与其他网络设备集成于工控机箱之中。 展开更多
关键词 MVB 网卡设计 UART emulation 单调比率算法 通信测试
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Simulation of long-distance pipeline transportation properties of whole-tailings paste with high sliming 被引量:18
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作者 WU Ai-xiang RUAN Zhu-en +4 位作者 WANG Yi-ming YIN Sheng-hua WANG Shao-yong WANG Yong WANG Jian-dong 《Journal of Central South University》 SCIE EI CAS CSCD 2018年第1期141-150,共10页
Based on Bingham rheological model,a three-dimensional numerical simulation model for long-distance pipeline transportation is established by computational fluid dynamics(CFD)to study the pipeline transportationproper... Based on Bingham rheological model,a three-dimensional numerical simulation model for long-distance pipeline transportation is established by computational fluid dynamics(CFD)to study the pipeline transportationproperties of high sliming paste from a copper mine in China.Based on the rheological properties test,the pressure and velocity of pipeline and elbow are simulated by CFD under different mass concentrations and different stowing capacities.The results show that the pipeline resistance of whole-tailings paste with high sliming while without pumping agent is much higher than that with high sliming and pumping agent at the same mass concentration,and the pipeline resistance of whole-tailings paste with high sliming while without pumping agent is much higher than that with low sliming while without pumping agent.It is very important to add pumping agent to whole-tailings paste with high sliming,and the resistance changes with mass concentration and stowing capacity at the same cement-to-sand ratio of1:5and tailings-to-waste ratio of6:1.However,the change is just limited,that is to say,the paste transportation system is of good stability.Furthermore,at the elbow,the maximum pressure and velocity transfer to the outside of the pipe from the inside.However,lubricating layer is formed at the pipe wall because of high content of fine particles in whole-tailings paste,which will protect the elbow from abrasion.CFD provides an intuitive and accurate basis for pipeline transportation study,and would have a wider application space in the study of paste rheological properties and resistance reduction methods. 展开更多
关键词 whole-tailings paste long-distance transportation computational fluid dynamics
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NFC技术Card Emulation模式在Android系统中的应用研究 被引量:5
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作者 杨振兴 《软件导刊》 2014年第2期113-115,共3页
近地场通讯(Near Field Communication,NFC)协议已被Android系统部分支持。随着Android手机的迅速普及,作为NFC三种工作模式之一的Card Emulation模式在电子考勤、移动支付等领域具有越来越广泛的应用潜力。尽管在Android 4.4版本之前... 近地场通讯(Near Field Communication,NFC)协议已被Android系统部分支持。随着Android手机的迅速普及,作为NFC三种工作模式之一的Card Emulation模式在电子考勤、移动支付等领域具有越来越广泛的应用潜力。尽管在Android 4.4版本之前公开的API并不支持Card Emulation模式,但由于Android本身的开源特征,借助开源项目SEEK或Android隐藏的API,仍可探索Card Emulation模式在Android系统上的应用。从NFC的特征和Android系统上NFC技术的实现出发,说明了Card Emulation模式的特点和应用场景,研究了Android系统上Card Emulation模式的现状和应用模式,分析了Card Emulation模式应用中的问题。 展开更多
关键词 近地场通信 CARD emulation 安全模块
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Pretreatment of emulational manual acupuncture versus electroacupuncture against visceral traction pain in rats 被引量:2
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作者 Huayuan Yang Tingting Guo +2 位作者 Youjiang Min Tangyi Liu Ming Gao 《Neural Regeneration Research》 SCIE CAS CSCD 2010年第10期741-746,共6页
BACKGROUND: Acupuncture and moxibustion against visceral noxious stimulation present different mechanisms in the peripheral and central nervous systems, involving release of neurotransmitter substance P, acetylcholin... BACKGROUND: Acupuncture and moxibustion against visceral noxious stimulation present different mechanisms in the peripheral and central nervous systems, involving release of neurotransmitter substance P, acetylcholine esterase, leucine-enkephalin, and c-Fos protein expression. However, there are few reports addressing changes in neurotransmitter expression following manual acupuncture and electroacupuncture against visceral traction pain.OBJECTIVE: To explore changes in neurotransmitter expression in the ileum and protein expression in the medullary visceral zone of visceral traction pain rats undergoing pretreatment of emulational manual acupuncture, and to investigate the differences between emulational manual acupuncture and electroacupuncture.DESIGN, TIME AND SETTING: The randomized, controlled study was performed at the Biomedical Engineering Laboratory, Shanghai University of Traditional Chinese Medicine, Shanghai, China from August 2008 to July 2009.MATERIALS: G6805 electroacupuncture apparatus (Shanghai Medical Electronic Machine Factory, China) and ZSF-I acupuncture manipulation simulation therapeutic system (Chinese Medical Engineering Room, Shanghai University of Traditional Chinese Medicine, Shanghai China) were used in the present study.METHODS: A total of 40 male Sprague Dawley rats were equally and randomly assigned to sham surgery, model, emulational manual acupuncture and electroacupuncture groups. In the emulational manual acupuncture and electroacupuncture groups, emulational manual acupuncture and electroacupuncture were applied at bilateral Zusanli (ST 36) acupoints for 30 minutes, and models of visceral traction pain were established immediately.MAIN OUTCOME MEASURES: Substance P expression, c-Fos and glial fibrillary acidic protein expression were measured using immunohistochemistry. Acetylcholine esterase activity was examined utilizing a colorimetric method. Leucine-enkephalin content was detected using a radioimmune assay. Degree of pain in rats was assessed by pain score.RESULTS: Pain score, substance P expression in the ileum, acetylcholine esterase activity, expression of c-Fos protein and glial fibrillary acidic protein in the medullary visceral zone were significantly decreased following pretreatment of emulational manual acupuncture and electroacupuncture in rats with visceral traction pain (P〈0.05). Compared with the electroacupuncture group, the leucine-enkephalin content was significantly increased, and pain score was significantly diminished in the emulational manual acupuncture group (P〈0.05).CONCLUSION: Emulational manual acupuncture pretreatment decreases acetylcholine esterase activity, increases leucine-enkephalin release, downregulates expression of c-Fos protein and glial fibrillary acidic protein and ultimately inhibits visceral traction pain by reducing substance P release. The effectiveness in inhibiting visceral traction pain is greater when using emulational manual acupuncture compared with electroacupuncture. This is because emulational manual acupuncture effectively increases leucine-enkephalin release. 展开更多
关键词 emulational manual acupuncture ELECTROACUPUNCTURE substance P LEUCINE-ENKEPHALIN acupuncture and moxibustion therapy visceral traction pain neural regeneration
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Study on the Technology of Supplying Water Safely by Long-Distance Pipeline 被引量:3
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作者 CHEN Yanbo YU Taipin +1 位作者 LIU Junhua ZHAO Hongbin 《Journal of Northeast Agricultural University(English Edition)》 CAS 2008年第3期80-85,共6页
The extensively built long-distance water transmission pipelines have become the main water sources for urban areas. To ensure the reliability and safety of the water supply, from the viewpoint of overall management, ... The extensively built long-distance water transmission pipelines have become the main water sources for urban areas. To ensure the reliability and safety of the water supply, from the viewpoint of overall management, it would be necessary to establish a system of information management for the pipeline. The monitoring, calculating and analyzing functions of the system serve to give controlling instructions and safe operating rules to the automatic equipment and technician, making sure the resistance coefficient distribution along the pipeline is reasonable; the hydraulic state transition is smooth when operating conditions change or water supply accidents occur, avoiding the damage of water hammer. This paper covered the composition structures of the information management system of long-distance water transmission pipelines and the functions of the subsystems, and finally elaborated on the approaches and steps of building a mathematics model for the analysis of dynamic hydraulic status. 展开更多
关键词 long-distance water transmission pipeline water supply security information management water hammer MODELING
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Study on the long-distance target apperception techniques for underwater vehicles 被引量:2
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作者 Yang Xudong Huang Jianguo Zhang Qunfei Tang Qi 《Journal of Systems Engineering and Electronics》 SCIE EI CSCD 2007年第3期484-490,共7页
The limited physical size for autonomous underwater vehicles (AUV) or unmanned underwater vehicles (UUV) makes it difficult to acquire enough space gain for localizing long-distance targets. A new technique about ... The limited physical size for autonomous underwater vehicles (AUV) or unmanned underwater vehicles (UUV) makes it difficult to acquire enough space gain for localizing long-distance targets. A new technique about long-distance target apperception with passive synthetic aperture array for underwater vehicles is presented. First, a synthetic aperture-processing algorithm based on the FFT transform in the beam space (BSSAP) is introduced. Then, the study on the flank array passive long-distance apperception techniques in the frequency scope of 11-18 kHz is implemented from the view of improving array gains, detection probability and augmenting detected range under a certain sea environment. The results show that the BSSAP algorithm can extend the aperture effectively and improve detection probability. Because of the augment of the transmission loss, the detected range has the trend of decline with the increase of frequency under the same target source level. The synthesized array could improve the space gain by nearly 7 dB and SNR is increased by about 5 dB. The detected range is enhanced to nearly 2 km under the condition of 108-118 dB of the target source level for AUV system in measurement interval of nearly 1 s. 展开更多
关键词 long-distance apperception synthetic aperture processing array gain detection probability detectedrange.
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Long-distance propagation of pseudo-partially coherent Gaussian Schell-model beams in atmospheric turbulence 被引量:2
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作者 钱仙妹 朱文越 饶瑞中 《Chinese Physics B》 SCIE EI CAS CSCD 2012年第9期259-266,共8页
Propagation properties of spatially pseudo-partially coherent Gaussian Schell-model beams through the atmo- spheric turbulence over a long-distance uplink path are studied by numerical simulation. A linear coordinatio... Propagation properties of spatially pseudo-partially coherent Gaussian Schell-model beams through the atmo- spheric turbulence over a long-distance uplink path are studied by numerical simulation. A linear coordination trans- formation is introduced to overcome the window effect and the loss-of-resolution problem. The beam spreading, beam wandering, and intensity scintillation as functions of turbulence strength, source correlation length, and change fre- quency of random phase that models the partial coherence of the source are analyzed. It is found that the beam spreading and the intensity scintillation of the partially coherent beam are less affected by the turbulence than those of the coherent one, but it suffers from a more severe diffractive effect, and the change frequency of random phase has no evident influence on it. The beam wandering is insensitive to the variation of source correlation length, and decreases firstly then goes to a fixed value as the change frequency increases. 展开更多
关键词 long-distance propagation pseudo-partially coherent Caussian Schell-model beam at-mospheric turbulence numerical simulation
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Improvement of heat-tolerance by training I. Evaluation of effects of long-distance running and march training on heat-tolerance 被引量:1
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作者 邱仞之 甄洪钧 +3 位作者 朱受成 万为人 刘汉湘 华旭初 《Journal of Medical Colleges of PLA(China)》 CAS 1995年第3期220-226,共7页
in order to verify the heat-tolerance effect, two trainings, 90 min marching with load (WBGT 24. 6~35.6℃) and 10 km running (WBGT 25.0~31.1℃) were performed in laboratory and field under hot climate.Ten to twelve ... in order to verify the heat-tolerance effect, two trainings, 90 min marching with load (WBGT 24. 6~35.6℃) and 10 km running (WBGT 25.0~31.1℃) were performed in laboratory and field under hot climate.Ten to twelve times (days) of training were carried out 展开更多
关键词 MARCH long-distance running TRAINING HEAT ACCLIMATIZATION heat-tolerance infantryman
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Influencing Factors of Seed Long-distance Dispersal on a Fragmented Forest Landscape on Changbai Mountains,China 被引量:1
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作者 ZHAO Fuqiang QI Lin +1 位作者 FANG Lei YANG Jian 《Chinese Geographical Science》 SCIE CSCD 2016年第1期68-77,共10页
Seed long-distance dispersal(LDD) events are typically rare, but are important in the population processes that determine large-scale forest changes and the persistence of species in fragmented landscapes. However, pr... Seed long-distance dispersal(LDD) events are typically rare, but are important in the population processes that determine large-scale forest changes and the persistence of species in fragmented landscapes. However, previous studies focused on species dispersed via animal-mediated LDD, and ignored those dispersed by wind. The aim of this study was to assess the effects of canopy openness, edge, seed source, and patch tree density on the LDD of seeds by wind in forest. We collected birch seeds, a typical wind-dispersed species, throughout a larch plantation. We then assessed the relationship between birch LDD and each factor that may influence LDD of seeds by wind including distance to edge, canopy openness size, distance to mature forest, and the tree density of the larch plantation. We used univariate linear regression analysis to assess the influence of those factors on birch LDD, and partial correlations to calculate the contribution of each factor to LDD. The results showed that both canopy openness and edge had significant influences on birch LDD. Specifically, a negative relationship was observed between distance to edge and birch LDD, whereas there was a positive correlation between canopy openness size and LDD. In contrast, the distance to the mature forest was not correlated with birch LDD. Our results suggest that patch tree density could potently affect the probability of LDD by wind vectors, which provides novel and revealing insights regarding the effect of fragmentation on wind dynamics. The data also provide compelling evidence for the previously undocumented effect of habitat fragmentation on wind-dispersed organisms. As such, these observations will facilitate reasonable conservation planning, which requires a detailed understanding of the mechanisms by which patch properties hamper the delivery of seeds of wind-dispersed plants to fragmented areas. 展开更多
关键词 seed long-distance dispersal (LDD) forest fragmentation patch property wind dispersal Changbai Mountains
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Criterions and Measures of Route Selection of Shallowly Embedded Long-Distance Oil and Gas Pipeline in Mountain Areas 被引量:1
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作者 WANG Chenghua MA Qingwen +2 位作者 KONG Jiming CHEN Zefu LI Xiuzhen 《Wuhan University Journal of Natural Sciences》 EI CAS 2006年第4期787-792,共6页
According to the engineering investigation of long-distance oil and gas pipelines, the criterions and measures of route selection are drawn as follows: the flat landform is the first choice in route alignment. The fo... According to the engineering investigation of long-distance oil and gas pipelines, the criterions and measures of route selection are drawn as follows: the flat landform is the first choice in route alignment. The foot of mountain is the first choice when the route passes by the valley. The route should pass by but the shady and deposited slope and not in sunny and erosive slope as possible as it can. The pipeline should be vertical to contour climbing and descending the mountain except steep slope. Tunnel can be used in crossing foothill. Perpendicularly traversing the river is better than beveling; the worst choice is to put the pipeline along the river. Bypass is the best choice in karsts area. The order of route selection should be pre-choosing, investigation, optimization and adjustment. 展开更多
关键词 shallowly embedded long-distance oil and gas pipeline criterions and measures of route selection avoiding geological hazards
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THE SYSTEMATIC DYNAMIC EMULATION ON THE AGRICULTURAL DEVELOPMENT ON THE LOESS PLATEAU
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作者 Lin Haiming Huang Gaobao +1 位作者 Chen Yuan Yu Shiming Gansu Agricultural University, Lanzhou, 730070 《干旱区资源与环境》 CSCD 1993年第Z1期471-475,共5页
The Loess Plateau, covered with thick loess, lies in the middle reaches of the YellowRiver to the west of the Taihangshan Mountains, east of the Wuqiao Mountains south ofYinshan Mountains and north of the Qinling Moun... The Loess Plateau, covered with thick loess, lies in the middle reaches of the YellowRiver to the west of the Taihangshan Mountains, east of the Wuqiao Mountains south ofYinshan Mountains and north of the Qinling Mountains with a total area of 56×10~4km^2.The plateau is 1000--2500m above sea level and has loess as thick as 100--200 metres, be- 展开更多
关键词 The LOESS PLATEAU SEMIARID Area Agricultural Region Systematic Dynamics emulation Study
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PARNEM-A PARALLEL DISCRETE EVENT NETWORK EMULATION SYSTEM
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作者 李越 钱德沛 何莹 《Journal of Pharmaceutical Analysis》 SCIE CAS 2006年第2期131-135,共5页
Objective Network emulation system constructs a virtual network environment which has the characteristics of controllable and repeatable network conditions. This makes it possible to predict the availability and perfo... Objective Network emulation system constructs a virtual network environment which has the characteristics of controllable and repeatable network conditions. This makes it possible to predict the availability and performance of new protocols and algorithms before deploying to Internet. Methods PARNEM, a parallel discrete event network emulation system described in this paper has the following characteristics: ① BREEN - a BSP based real-time event scheduling engine; ② application transparent flexible interactive mechanism; ③ legacy network model reuse. Conclusion PARNEM allows detailed and accurate study of application behavior. Comprehensive case studies covering bottleneck bandwidth measurement and distributed cooperative web caching system demonstrate that network emulation technology opens a wide range of new opportunities for examining the behavior of applications. 展开更多
关键词 network emulation performance evaluation interactive mechanism
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Optimized Implementation for Wave Digital Filter Based Circuit Emulation on FPGA
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作者 Yue Ma Shun'an Zhong Shiwei Ren 《Journal of Beijing Institute of Technology》 EI CAS 2017年第2期235-244,共10页
A binary tree representation is designed in this paper for optimization of wave digital filter(WDF)implementation.To achieve this,an equivalent WDF model of the original circuit is converted into abinary tree repres... A binary tree representation is designed in this paper for optimization of wave digital filter(WDF)implementation.To achieve this,an equivalent WDF model of the original circuit is converted into abinary tree representation at first.This WDF binary tree can then be transformed to several topologies with the same implication,since the WDF adaptors have a symmetrical behavior on their ports.Because the WDF implementation is related to field programmable gate array(FPGA)resource usage and the cycle time of emulation,choosing aproper binary tree topology for WDF implementation can help balance the complexity and performance quality of an emulation system.Both WDF-FPGA emulation and HSpice simulation on the same circuit are tested.There is no significant difference between these two simulations.However,in terms of time consumption,the WDF-FPGA emulation has an advantage over the other.Our experiment also demonstrates that the optimized WDF-FPGA emulation has an acceptable accuracy and feasibility. 展开更多
关键词 analog circuit emulation wave digital filter (WDF) field programmable gate array(FPGA)
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THE RISK ASSESSMENT OF THE LONG-DISTANCE OILPIPELINE ENGINEERING
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作者 Wang Jinghua Mu Congru(Institute of Geography, CAS, Beijing 100101People’s Republic of China) 《Journal of Geographical Sciences》 SCIE CSCD 1996年第1期78-83,共6页
The oilfield construction and long-distance oil pipeline engineering has been developed extensively in China. The risk assessment of oil industry will, however, be an important objective to cope with the development o... The oilfield construction and long-distance oil pipeline engineering has been developed extensively in China. The risk assessment of oil industry will, however, be an important objective to cope with the development of oil industry , The risk assessment of oil industry has many subjects worthy to be studied.The major purpose of the paper is to research the risk cases of long-distance oil pipeline engineering in Ganshu and Shaanxi provinces. 展开更多
关键词 long-distance oil pipeline risk assessment ENGINEERING GANSU SHAANXI
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A Large-Scale NFV-Based Emulation Platform for Smart Identifier Network
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作者 LI Haifeng LI Taixin ZHANG Hongke 《ZTE Communications》 2017年第3期2-7,共6页
Network emulation is significant because of its ability to study network architecture running on real operating system and thewhole protocol stack. However, conservatively allocating a physical network equipment for a... Network emulation is significant because of its ability to study network architecture running on real operating system and thewhole protocol stack. However, conservatively allocating a physical network equipment for a corresponding emulation network iscostly, scale-limited and rigid. In this paper, based on network function virtualization(NFV), we present a large-scale emulationplatform for the Smart Identifier Network(SINET). We pool and virtualize all hardware resources by lightweight virtualization technology. Controllers and orchestrators are designed to manage emulation and collect monitored SINET emulation results. The controllers are used to implement dynamically synchronously management for large-scale emulation network and link characteristics.The orchestrators are utilized to achieve overload avoidance and green computing with the Xiao's dynamic resource allocation algorithm. We implement flexibly programmable and dynamically configurable emulation. 展开更多
关键词 NFV SINET emulation VIRTUALIZATION control ORCHESTRATION
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