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Molecular mechanisms underlying microglial sensing and phagocytosis in synaptic pruning 被引量:1
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作者 Anran Huo Jiali Wang +6 位作者 Qi Li Mengqi Li Yuwan Qi Qiao Yin Weifeng Luo Jijun Shi Qifei Cong 《Neural Regeneration Research》 SCIE CAS CSCD 2024年第6期1284-1290,共7页
Microglia are the main non-neuronal cells in the central nervous system that have important roles in brain development and functional connectivity of neural circuits.In brain physiology,highly dynamic microglial proce... Microglia are the main non-neuronal cells in the central nervous system that have important roles in brain development and functional connectivity of neural circuits.In brain physiology,highly dynamic microglial processes are facilitated to sense the surrounding environment and stimuli.Once the brain switches its functional states,microglia are recruited to specific sites to exert their immune functions,including the release of cytokines and phagocytosis of cellular debris.The crosstalk of microglia between neurons,neural stem cells,endothelial cells,oligodendrocytes,and astrocytes contributes to their functions in synapse pruning,neurogenesis,vascularization,myelination,and blood-brain barrier permeability.In this review,we highlight the neuron-derived“find-me,”“eat-me,”and“don't eat-me”molecular signals that drive microglia in response to changes in neuronal activity for synapse refinement during brain development.This review reveals the molecular mechanism of neuron-microglia interaction in synaptic pruning and presents novel ideas for the synaptic pruning of microglia in disease,thereby providing important clues for discovery of target drugs and development of nervous system disease treatment methods targeting synaptic dysfunction. 展开更多
关键词 COMPLEMENT immune signals microglia molecular signal synapse elimination synapse formation synapse refinement synaptic pruning
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An Investigation of Frequency-Domain Pruning Algorithms for Accelerating Human Activity Recognition Tasks Based on Sensor Data
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作者 Jian Su Haijian Shao +1 位作者 Xing Deng Yingtao Jiang 《Computers, Materials & Continua》 SCIE EI 2024年第11期2219-2242,共24页
The rapidly advancing Convolutional Neural Networks(CNNs)have brought about a paradigm shift in various computer vision tasks,while also garnering increasing interest and application in sensor-based Human Activity Rec... The rapidly advancing Convolutional Neural Networks(CNNs)have brought about a paradigm shift in various computer vision tasks,while also garnering increasing interest and application in sensor-based Human Activity Recognition(HAR)efforts.However,the significant computational demands and memory requirements hinder the practical deployment of deep networks in resource-constrained systems.This paper introduces a novel network pruning method based on the energy spectral density of data in the frequency domain,which reduces the model’s depth and accelerates activity inference.Unlike traditional pruning methods that focus on the spatial domain and the importance of filters,this method converts sensor data,such as HAR data,to the frequency domain for analysis.It emphasizes the low-frequency components by calculating their energy spectral density values.Subsequently,filters that meet the predefined thresholds are retained,and redundant filters are removed,leading to a significant reduction in model size without compromising performance or incurring additional computational costs.Notably,the proposed algorithm’s effectiveness is empirically validated on a standard five-layer CNNs backbone architecture.The computational feasibility and data sensitivity of the proposed scheme are thoroughly examined.Impressively,the classification accuracy on three benchmark HAR datasets UCI-HAR,WISDM,and PAMAP2 reaches 96.20%,98.40%,and 92.38%,respectively.Concurrently,our strategy achieves a reduction in Floating Point Operations(FLOPs)by 90.73%,93.70%,and 90.74%,respectively,along with a corresponding decrease in memory consumption by 90.53%,93.43%,and 90.05%. 展开更多
关键词 Convolutional neural networks human activity recognition network pruning frequency-domain transformation
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Pruning Techniques for Prunus mume
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作者 JI Hao 《Journal of Landscape Research》 2024年第3期66-69,共4页
Prunusmumehas high ornamental value,and its maintenance and management should be more meticulous,with pruning being an important task.Pruning can make P.mume more robust,reduce the occurrence of diseases and pests,mai... Prunusmumehas high ornamental value,and its maintenance and management should be more meticulous,with pruning being an important task.Pruning can make P.mume more robust,reduce the occurrence of diseases and pests,maintain a good shape,and promote more flowering,further improving its ornamental value.The difficulty of pruning lies in flexibly adopting suitable pruning methods according to the time of the tree,which requires understanding the impact of pruning operations on the growth and flowering of P.mume,as well as some techniques in pruning operations.This paper introduces the botanical characteristics of P.mume,common pruning methods and achievable effects of P.mume,and suitable time for using various methods,and analyzes the possible consequences and reasons of some incorrect operations.Moreover,corresponding correct practices are provided,which can provide reference for standardized pruning of P.mume,thereby reducing or avoiding losses caused by improper operation. 展开更多
关键词 Prunusmume pruning Viewing TECHNOLOGY
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Joint On-Demand Pruning and Online Distillation in Automatic Speech Recognition Language Model Optimization
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作者 Soonshin Seo Ji-Hwan Kim 《Computers, Materials & Continua》 SCIE EI 2023年第12期2833-2856,共24页
Automatic speech recognition(ASR)systems have emerged as indispensable tools across a wide spectrum of applications,ranging from transcription services to voice-activated assistants.To enhance the performance of these... Automatic speech recognition(ASR)systems have emerged as indispensable tools across a wide spectrum of applications,ranging from transcription services to voice-activated assistants.To enhance the performance of these systems,it is important to deploy efficient models capable of adapting to diverse deployment conditions.In recent years,on-demand pruning methods have obtained significant attention within the ASR domain due to their adaptability in various deployment scenarios.However,these methods often confront substantial trade-offs,particularly in terms of unstable accuracy when reducing the model size.To address challenges,this study introduces two crucial empirical findings.Firstly,it proposes the incorporation of an online distillation mechanism during on-demand pruning training,which holds the promise of maintaining more consistent accuracy levels.Secondly,it proposes the utilization of the Mogrifier long short-term memory(LSTM)language model(LM),an advanced iteration of the conventional LSTM LM,as an effective alternative for pruning targets within the ASR framework.Through rigorous experimentation on the ASR system,employing the Mogrifier LSTM LM and training it using the suggested joint on-demand pruning and online distillation method,this study provides compelling evidence.The results exhibit that the proposed methods significantly outperform a benchmark model trained solely with on-demand pruning methods.Impressively,the proposed strategic configuration successfully reduces the parameter count by approximately 39%,all the while minimizing trade-offs. 展开更多
关键词 Automatic speech recognition neural language model Mogrifier long short-term memory pruning DISTILLATION efficient deployment OPTIMIZATION joint training
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Physicochemical Properties of Combustion Ashes of Some Trees(Urban Pruning)Present in the Neotropical Region
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作者 John Freddy Gelves-Díaz Ludovic Dorkis +2 位作者 Richard Monroy-Sepúlveda Sandra Rozo-Rincón Yebrail Alexis Romero-Arcos 《Journal of Renewable Materials》 EI 2023年第10期3769-3787,共19页
Secondary lignocellulosic biomass has proved to be useful as an energy source through its oxidation by means of combustion processes.In accordance with the above,in this paper,we wanted to study the ash from urban pru... Secondary lignocellulosic biomass has proved to be useful as an energy source through its oxidation by means of combustion processes.In accordance with the above,in this paper,we wanted to study the ash from urban pruning residues that are generated in cities in the Neotropics.Species such as Licania tomentosa,Azadirachta indica,Ficus benjamina,Terminalia catappa,Leucaena leucocephala,Prosopis juliflora and Pithecellobium dulce were selected because they have been previously studied and showed potential for thermal energy generation.These materials were calcined in an oxidizing atmosphere and characterized by X-ray diffraction and fluorescence,scanning electron microscopy with microchemistry,BET surface area,thermal gravimetric analysis,and differential scanning calorimetry.The pH and apparent density were also established.The results show high basicity materials(average pH 10),a behavior associated with the presence of chemical elements such as calcium,potassium,magnesium,chlorine,phosphorus,and sulfur.Structurally,these materials have a very significant amorphous fraction(between 49%and 74.5%),the dominant crystalline phases are calcite,arcanite,sylvite,and hydroxyapatite.These ashes have low surface area and do not exceed 13 m^(2)/g.Two characteristic morphological aspects were observed in these ashes:a morphology of rounded grains where silicon content is highlighted,and lamellar morphologies where the presence of chlorine is highlighted.Thermally,these ashes show four significant mass loss events(400℃,430℃,680℃,and 920℃),causing mass losses that vary between 25%and 40%.Through this study,it was possible to establish that,from a chemical point of view,these ashes are less dangerous in comparison with those of a mineral coal that was used as a reference.However,they require additional treatments for their disposal due to their high basicity.Because of their composition,these ashes have the potential to be used in the ceramic and cement industries,and in the manufacture of fertilizers. 展开更多
关键词 Bottom ash chemical composition characterization MINERALOGY plant biomass pruning residues urban flora
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Pedestrian and Vehicle Detection Based on Pruning YOLOv4 with Cloud-Edge Collaboration
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作者 Huabin Wang Ruichao Mo +3 位作者 Yuping Chen Weiwei Lin Minxian Xu Bo Liu 《Computer Modeling in Engineering & Sciences》 SCIE EI 2023年第11期2025-2047,共23页
Nowadays,the rapid development of edge computing has driven an increasing number of deep learning applications deployed at the edge of the network,such as pedestrian and vehicle detection,to provide efficient intellig... Nowadays,the rapid development of edge computing has driven an increasing number of deep learning applications deployed at the edge of the network,such as pedestrian and vehicle detection,to provide efficient intelligent services to mobile users.However,as the accuracy requirements continue to increase,the components of deep learning models for pedestrian and vehicle detection,such as YOLOv4,become more sophisticated and the computing resources required for model training are increasing dramatically,which in turn leads to significant challenges in achieving effective deployment on resource-constrained edge devices while ensuring the high accuracy performance.For addressing this challenge,a cloud-edge collaboration-based pedestrian and vehicle detection framework is proposed in this paper,which enables sufficient training of models by utilizing the abundant computing resources in the cloud,and then deploying the well-trained models on edge devices,thus reducing the computing resource requirements for model training on edge devices.Furthermore,to reduce the size of the model deployed on edge devices,an automatic pruning method combines the convolution layer and BN layer is proposed to compress the pedestrian and vehicle detection model size.Experimental results show that the framework proposed in this paper is able to deploy the pruned model on a real edge device,Jetson TX2,with 6.72 times higher FPS.Meanwhile,the channel pruning reduces the volume and the number of parameters to 96.77%for the model,and the computing amount is reduced to 81.37%. 展开更多
关键词 Pedestrian and vehicle detection YOLOv4 channel pruning cloud-edge collaboration
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Impact of Progressive Pruning on Leaf Miner (Coelaenomenodera lameensis) Incidence and the Yield of Oil Palm (Elaeis guineensis) —A Case Study of Benso Oil Palm Plantation Plc, Adum Banso Estate, Ghana
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作者 Isaac Addo Emmanuel Ackah +5 位作者 Samuel Avaala Awonnea Kwasi Baah Ofori Victor Tetteh Zutah Geoffrey Smith Oduro Esther Fobi Donkor Kwadwo Gyasi Santo 《American Journal of Plant Sciences》 CAS 2023年第3期377-389,共13页
The oil palm leaf miner, Coelaenomenodera lameensis, is currently the most destructive pest of oil palm in Ghana and other African oil palm growing countries, causing significant losses in fresh fruit bunch yield. Pro... The oil palm leaf miner, Coelaenomenodera lameensis, is currently the most destructive pest of oil palm in Ghana and other African oil palm growing countries, causing significant losses in fresh fruit bunch yield. Progressive pruning is an oil palm pruning method in which pruning is done at the same time as fresh fruit bunch harvesting. This study evaluated the impact of progressive pruning on leaf miner population in oil palm and how these two factors (leaf miner and progressive pruning) affect the yield of oil palm at the Benso Oil Palm Plantation Public listed company (BOPP. Plc). Five distinct blocks in the plantation were selected for observations on fronds at various ranks (33, 25, or 17) based on the degree of defoliation by counting the number of pests on leaflets at different phases of insect development. Fronds from selected plots were sampled in a Completely Randomized Design (CRD). The size of plots used for the study ranged between 19 to 45 hectares. A minimum of 78 fronds were evenly cut from each block for pest count depending on the block size. Secondary data on annual yields of fresh fruit bunches before and after the introduction of progressive pruning were also obtained from BOPP. Plc records from 2011-2020. The results from the analyzed data on leaf miner index before and after the introduction of progressive pruning showed that progressive pruning has, to a high extent (64% to 36%), reduced leaf miner populations in the plantation. Paired t-test on fresh fruit bunch yield has also revealed a significant (p < 0.001) increase in annual fresh fruit bunch yield due to progressive pruning. A regression analysis, however, revealed a lower rate of yield loss (3.05 to 2.70 tonnes) to leaf miner infestation after the introduction of progressive pruning. The study recommends progressive pruning as a key cultural practice for improving crop yields in leaf miner prone plantations. 展开更多
关键词 Coelaenomenodera lameensis Elaeis spp Leaf Miner Oil Palm Progressive pruning Fresh Fruit Bunch BOPP. Plc
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Effects of Pruning Methods on the Growth and Development of New Shoots and Fruit Yield and Quality of Walnut
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作者 ABDUXUKUR Yakup MUHTAR Zari MANSUR Nasir 《Agricultural Biotechnology》 CAS 2021年第5期1-4,共4页
[Objectives]This study was conducted to screen out reasonable pruning methods of walnut,and provide practical guidance for high-yield cultivation of walnut.[Methods]Xinfeng and Xinguang were used to study the effects ... [Objectives]This study was conducted to screen out reasonable pruning methods of walnut,and provide practical guidance for high-yield cultivation of walnut.[Methods]Xinfeng and Xinguang were used to study the effects of mechanical and artificial pruning methods on shoot growth,chlorophyll content in leaves,net photosynthetic rate and fruit quality.[Results]The results showed that:①the pruning method had a significant impact on the number of new shoots,and the number of new shoots of mechanical pruning was significantly higher than that of manual pruning;②the pruning method had a significant impact on the chlorophyll content,and the chlorophyll content of Xinguang of mechanical pruning was significantly higher than that of manual pruning;③the pruning method had a significant impact on the net photosynthetic rate of leaves,and the net photosynthetic rate of manual pruning was significantly higher than that of manual pruning;④Pruning methods had a significant effect on the number of walnut fruit,and the fruit trees pruned manually were significantly higher than those pruned mechanically;⑤the pruning method had no significant impact on the single fruit weight;⑥Pruning methods had a significant effect on the shell yield of a single walnut plant.The shell yield of single walnut plant pruned manually was significantly higher than that pruned mechanically;⑦pruning mode had a significant impact on the yield of walnut per plant,and the yield of artificially pruned walnut per plant was significantly higher than that of mechanical pruning;and⑧Xinfeng s chlorophyll content,net photosynthetic rate,fruit number,shell yield per plant and kernel yield per plant were all better than that of Xinguang,in addition,the growth and development of new shoots,the fruit quantity and quality of fruit also were affected by the interaction effect of genotype and pruning mode×variety.[Conclusions]It can be seen that different pruning methods have significant effects on the growth and development of new shoots and fruit yield and quality of walnut.Artificial pruning is more suitable for walnut cultivation by adjusting photosynthesis and improving the yield and quality of walnut;and Xinfeng is more suitable for popularization and production. 展开更多
关键词 WALNUT pruning method Manual pruning Mechanical pruning
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Analysis on Fuji Apple Tree Structures and Related Factors under Different Pruning Modes 被引量:1
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作者 郝婕 索相敏 +4 位作者 李学营 魏亮 王献革 鄢新民 冯建忠 《Agricultural Science & Technology》 CAS 2017年第12期2528-2531,2535,共5页
To determine the correlations between the tree structuresof Fuji apple with different pruning modes and each factor, the data about 3 tree structures which were free spindle short shoot, free spindle long shoot and sl... To determine the correlations between the tree structuresof Fuji apple with different pruning modes and each factor, the data about 3 tree structures which were free spindle short shoot, free spindle long shoot and slenderspindle short shoot in Xingtang County of Hebai Province were investigated, then by SPSS anal- ysis, the correlations between the taperingness and each growth factor of inserted small branch were compared. The results showed that the taperingness of central trunk of free spindle dwarf-shoot Fuji apple treeshad negative correlations with each factor of inserted small branch, while the taperingness of central trunk of free spin- dle long-shoot Fuji apple treeshad positive correlations with each factor of inserted small branch, the taperingness of central trunk of slenderspindle short-shootFuji ap- ple treeshad negative correlation with total thickness of inserted small branch, but had positive correlations with other factors. This study can provide a scientifictheo- retical basis for the pruning technology of high-density planting trees grafting by dwarfing self-rooted rootstock. 展开更多
关键词 pruning Fuji apple Tree structures Analysis of related factors
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Analysis on Apple Tree Structures by Free Spindle Pruning Mode
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作者 郝婕 索相敏 +3 位作者 李学营 王献革 鄢新民 冯建忠 《Agricultural Science & Technology》 CAS 2016年第10期2238-2241,共4页
To determine the correlation between the stem taperingness and central shaft by free spindle pruning mode on different apple cultivars, the central shaft growth data of three cultivars of free spindle short shoot "F... To determine the correlation between the stem taperingness and central shaft by free spindle pruning mode on different apple cultivars, the central shaft growth data of three cultivars of free spindle short shoot "Fuji", free spindle long shoot "Fuji", free spindle "Huaguan" were investigated in Xingtang County of Hebei Province by SPSS analysis. The results showed that the stem taperingness on free spindle short shoot "Fuji" was in negative correlation with central shaft, but the correlation was not significant. While the stem taperingness on free spindle long shoot "Fuji" was in positive correlation with central shaft, but the correlation was not significant either. The stern taperingness on free spindle "Huaguan" was in negative correlation with central shaft, and the correlation between the stem taperingness and the central shaft total length was significant at the level of 0.01. The results.provided scientific theoretical basis for guiding the dwarfing rootstocks close planting apple tree pruning technology. 展开更多
关键词 APPLE Free spindle pruning mode Structure analysis
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改进的基于FFT pruning的窄带高分辨率频谱算法 被引量:3
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作者 王琰 万群 杨万麟 《计算机工程与应用》 CSCD 北大核心 2007年第26期54-55,141,共3页
提出一种改进的基于FFT pruning的窄带高分辨率频谱计算方法。该方法是对Sreenivas's FFT pruning算法和Nagai的利用频移变换的FFT pruning算法的推广。同时提出输出点分级思想,可实现任意窄带上非2的整数幂次频点输出。该算法比Sre... 提出一种改进的基于FFT pruning的窄带高分辨率频谱计算方法。该方法是对Sreenivas's FFT pruning算法和Nagai的利用频移变换的FFT pruning算法的推广。同时提出输出点分级思想,可实现任意窄带上非2的整数幂次频点输出。该算法比Sreenivas's FFT pruning算法具有更小的计算量和更简单的信号流图。 展开更多
关键词 FFT pruning 窄带 频移
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Effects of Pruning Treatments on Yield and Economic Benefits of Pepper in Greenhouse during Long-season Cultivation 被引量:2
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作者 袁野 杨剑 +2 位作者 童辉 彭莹 袁祖华 《Agricultural Science & Technology》 CAS 2016年第3期593-595,共3页
In the Yangtze River region, thepepper long-season cultivation needs oversummer pruning. Inorder to study the effects of different pruning treatments on growth of over-summer grown pepper, three differentpruning treat... In the Yangtze River region, thepepper long-season cultivation needs oversummer pruning. Inorder to study the effects of different pruning treatments on growth of over-summer grown pepper, three differentpruning treatments were applied to pepper seedlings, such as treatment one(re-growth pruning), treatment two(four stems) and treatment three(multi-stem pruning) with no pruning as control(CK).The results showed that themulti-stem pruning treatment enabling the plant to maintain the good plant type for high yield and reduce thevirus disease to improve the marketability of pepper fruits, compared with the other two pruning treatments;andthe yield and economic benefit were increased by 15.8% and 19%, compared with the control, respectively. Ingeneral the multi-stem pruning was the best for over-summer pepper cultivation. 展开更多
关键词 pruning treatment PEPPER Over-summer cultivation
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一种改进的FFT Pruning算法及其在塔康载波频率测量中的应用 被引量:1
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作者 彭大国 李治安 +2 位作者 李晓明 裴文林 牛诚旻 《南京邮电大学学报(自然科学版)》 北大核心 2015年第1期66-71,共6页
提出了一种改进的FFT Pruning算法。将Nagai提出的频移思想和Alves提出的辅助矩阵思想结合起来,对信号流图和辅助矩阵进行简化。对输出频点数与辅助矩阵列数的关系进行研究,降低了辅助矩阵的大小,并推导出辅助矩阵的表达式。将改进后的... 提出了一种改进的FFT Pruning算法。将Nagai提出的频移思想和Alves提出的辅助矩阵思想结合起来,对信号流图和辅助矩阵进行简化。对输出频点数与辅助矩阵列数的关系进行研究,降低了辅助矩阵的大小,并推导出辅助矩阵的表达式。将改进后的算法运用到塔康载波频率测量中,先用少点数的FFT进行频率粗搜索,再用改进的FFT Pruning算法进行频率精测。仿真结果表明,改进算法能在运算量不大的情况下实现对塔康载波频率的高精度测量。 展开更多
关键词 FFT pruning 辅助矩阵 塔康 频率测量
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一种改进的基于FFT Pruning算法的快速实现方法 被引量:1
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作者 李忠慧 曾毓敏 +1 位作者 尹晓琦 吴婷婷 《南京师范大学学报(工程技术版)》 CAS 2005年第4期42-45,共4页
针对文献[5]提出的FFT Prun ing算法作了一些改进,得到了只计算FFT频谱中部分频点谱值的改进的快速实现方法.根据输入输出数据的结构特点,利用辅助矩阵和数据复制等手段,降低了FFT Prun ing算法实现的复杂度,提高了FFTPrun ing算法实现... 针对文献[5]提出的FFT Prun ing算法作了一些改进,得到了只计算FFT频谱中部分频点谱值的改进的快速实现方法.根据输入输出数据的结构特点,利用辅助矩阵和数据复制等手段,降低了FFT Prun ing算法实现的复杂度,提高了FFTPrun ing算法实现的灵活性.将改进后的FFT Prun ing算法用C语言实现并在DSP集成开发环境CCS下的C5402 D evice S im-u lator上运行.在相同条件下,再运行一般意义上的FFT算法和文献[5]中算法所对应的C程序,统计3种方法的运行时间并比较他们的效率.仿真结果表明:在相同的条件下,改进后的算法在快速准确地得到相关频谱值的同时,运算时间明显少于另外两种方法.同时,对输入输出端所取数据的长度也没有任何限制. 展开更多
关键词 FFT pruning算法 算法实现 数字信号处理 频谱分辨率
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Effect of pruning intensity on soil moisture and water use efficiency in jujube(Ziziphus jujube Mill.) plantations in the hilly Loess Plateau Region, China 被引量:6
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作者 JIN Shanshan WANG Youke +2 位作者 WANG Xing BAI Yonghong SHI Leigang 《Journal of Arid Land》 SCIE CSCD 2019年第3期446-460,共15页
Jujube(Ziziphus jujube Mill.)is a traditional economic forest crop and is widely cultivated in hilly areas of the Loess Plateau,China.However,soil desiccation was discovered in jujube plantations.Pruning is recognized... Jujube(Ziziphus jujube Mill.)is a traditional economic forest crop and is widely cultivated in hilly areas of the Loess Plateau,China.However,soil desiccation was discovered in jujube plantations.Pruning is recognized as a water-saving method that can reduces soil water consumption.In this study,we monitored the jujube plots with control(CK),light(C1),medium(C2)and high(C3)pruning intensities during the jujube growing period of 2012-2015 to explore the effect of pruning intensity on soil moisture and water use efficiency(WUE)of jujube plantations in the hilly Loess Plateau Region.The results showed that pruning is an effective method for soil water conservation in jujube plantations.Soil moisture increased with increasing pruning intensity during the jujube growing period of 2012-2015.C1,C2 and C3 pruning intensities increased soil water storage by 6.1-18.3,14.4-40.0 and 24.3-63.3 mm,respectively,compared to CK pruning intensity.Pruning promoted soil moisture infiltration to deeper soil layer.Soil moisture infiltrated to soil depths of 240,280 and>300 cm under C3 pruning intensity,220,260 and 260 cm under C2 pruning intensity,200,240 and 220 cm under C1 pruning intensity,and 180,200 and 160 cm under CK pruning intensity in 2013,2014 and 2015,respectively.Soil water deficit was alleviated by higher pruning intensity.In 2013-2015,soil water change was positive under C2(6.4 mm)and C3(26.8 mm)pruning intensities but negative under C1(-20.5 mm)and CK(-40.6 mm)pruning intensities.Moreover,pruning significantly improved fresh fruit yield and WUE of jujube plants.Fresh fruit yields were highest under C1 pruning intensity with the values of 6897.1-13,059.3 kg/hm^2,which were 2758.4-4712.8,385.7-1432.1 and 802.8-2331.5 kg/hm2 higher than those under CK,C2,and C3 pruning intensities during the jujube growing period of 2012-2015,respectively.However,C3 pruning intensity had the highest WUE values of 2.92-3.13 kg/m3,which were 1.6-2.0,1.1-1.2 and 1.0-1.1 times greater than those under CK,C1 and C2 pruning intensities,respectively.Therefore,C3 pruning intensity is recommended to jujube plantations for its economic and ecological benefits.These results provide an alternative strategy to mitigate soil desiccation in jujube plantations in the hilly Loess Plateau Region,which is critical for sustainable cultivation of economic forest trees in this region. 展开更多
关键词 pruning intensity soil DESICCATION yield water use efficiency Ziziphusjujube Mill. LOESS Plateau
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Improved pruning algorithm for Gaussian mixture probability hypothesis density filter 被引量:7
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作者 NIE Yongfang ZHANG Tao 《Journal of Systems Engineering and Electronics》 SCIE EI CSCD 2018年第2期229-235,共7页
With the increment of the number of Gaussian components, the computation cost increases in the Gaussian mixture probability hypothesis density(GM-PHD) filter. Based on the theory of Chen et al, we propose an improved ... With the increment of the number of Gaussian components, the computation cost increases in the Gaussian mixture probability hypothesis density(GM-PHD) filter. Based on the theory of Chen et al, we propose an improved pruning algorithm for the GM-PHD filter, which utilizes not only the Gaussian components’ means and covariance, but their weights as a new criterion to improve the estimate accuracy of the conventional pruning algorithm for tracking very closely proximity targets. Moreover, it solves the end-less while-loop problem without the need of a second merging step. Simulation results show that this improved algorithm is easier to implement and more robust than the formal ones. 展开更多
关键词 Gaussian mixture probability hypothesis density(GM-PHD) filter pruning algorithm proximity targets clutter rate
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Effects of Root Pruning on Non-Hydraulic Root-Sourced Signal, Drought Tolerance and Water Use Efficiency of Winter Wheat 被引量:5
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作者 MA Shou-chen LI Feng-min +3 位作者 YANG Shen-jiao LI Chun-xi XU Bing-cheng ZHANG Xu-cheng 《Journal of Integrative Agriculture》 SCIE CAS CSCD 2013年第6期989-998,共10页
Two pot experiments were conducted to study the effects of root pruning at the stem elongation stage on non-hydraulic root-sourced signals (nHRS), drought tolerance and water use efficiency of winter wheat (Triticu... Two pot experiments were conducted to study the effects of root pruning at the stem elongation stage on non-hydraulic root-sourced signals (nHRS), drought tolerance and water use efficiency of winter wheat (Triticum aestivum). The root pruning significantly reduced the root weight of wheat, but had no effect on root/shoot ratio at the two tested stages. At booting stage, specific root respiration of root pruned plants was significantly higher than those with intact roots (1.06 and 0.94 mmol g-1 s-1, respectively). The soil water content (SWC) at which nHRS for root pruned plants appeared was higher and terminated lower than for intact root plants, the threshold range of nHRS was markedly greater for root pruned plants (61.1-44.6% field water capacity) than for intact root plants (57.9-46.1% field water capacity). At flowering stage, while there was no significant difference in specific root respiration. The SWCs at which nHRS appeared and terminated were both higher for root pruned plants than for intact root plants. The values of chlorophyll fluorescence parameters, i.e., the effective photosystem II quantum yield (F PS II ), the maximum photochemical efficiency of PS II (F v /F m ), coefficient of photochemical quenching (qP), and coefficient of non-photochemical quenching (NPQ), in root pruned plants were significantly higher than in intact root plants, 7 d after withholding of water. Root pruned plants had significantly higher water use efficiency (WUE) than intact root plants in well-watered and medium drought soil, but not in severe drought condition. In addition, root pruning had no significant effect on grain yield in well-watered and medium drought soil, but significantly decreased grain yield in severe drought condition. In conclusion, the current study showed that root pruning significantly altered nHRS sensitivity and improved WUE of winter wheat in well-watered and medium drought soil, but lowered drought tolerance of winter wheat in severe drought soil. This suggests a possible direction of drought- resistance breeding and potential agricultural measure to improve WUE of winter wheat under semiarid conditions. 展开更多
关键词 winter wheat root pruning non-hydraulic root-sourced signal (nHRS) root activity drought tolerance
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Nitrogen Mineralization of Prunings of Six N_2-Fixing Hedgerow Species in a Dry Valley of the Jinsha River 被引量:7
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作者 SUN HUI, TANG YA and ZHAO QIGUO Institute of Soil Science, the Chinese Academy of Sciences, Nanjing, 210008 (China) Chengdu Institute of Biology, the Chinese Academy of Sciences, Chengdu 610041 (China) 《Pedosphere》 SCIE CAS CSCD 2002年第1期25-31,共7页
A litterbag experiment of 12 weeks was conducted to study nitrogenmineralization process of prunings of six nitrogen-fixing hedgerowspecies in a dry valley of the Jinsha River. Prunigns wereincorporated into soil or u... A litterbag experiment of 12 weeks was conducted to study nitrogenmineralization process of prunings of six nitrogen-fixing hedgerowspecies in a dry valley of the Jinsha River. Prunigns wereincorporated into soil or used as mulch. The results indicated thatpruning N of the six hedgerow species was mineralized fast in thefirst week and then decreased slowly in the rest of the study period.When prunings were incorporated into soil, the amount of nitrogenmineralized by the end of the first week accounted for 69.9/100,58.2/100, 54.5/100, 43.0/100, 29.6/100 and 20.6/100 of the total N inprungins of Desmodium rensonii, Tephrosia candida, Leucaenaleucoephala, Albizia yunnanensis, Acacia dealbata, and Acaciamearnsii, respectively. 展开更多
关键词 contour hedgerow system MINERALIZATION N prunings
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Effect of first thinning and pruning on the individual growth of Pinus patula tree species 被引量:4
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作者 Edward Missanjo Gift Kamanga-Thole 《Journal of Forestry Research》 SCIE CAS CSCD 2015年第4期827-831,共5页
The effect of first thinning and pruning on height, diameter at breast height (DBH), and volume growth was studied in individual trees of Pinus patula Schiede and Deppe in Chongoni Plantation, using four plots for t... The effect of first thinning and pruning on height, diameter at breast height (DBH), and volume growth was studied in individual trees of Pinus patula Schiede and Deppe in Chongoni Plantation, using four plots for thinning trials. Each of the plots was 0.5 ha and subjected to one of the fol- lowing silvicultural treatments: first thinning and pruning, first thinning and no pruning, pruning and no thinning, and control (no pruning and no thinning). The silvicultural treatments were randomized in four replicates. Fourteen years after planting, the following parameters were measured including total height, DBH, and volume. The highest DBH and volume growth was observed in thinning and pruning, while the highest growth in height was observed where there was pruning and no thinning. Clearly, both thinning and pruning are an important manage- ment option in pine species plantations in Malawi to maximize the increase in volume productivity. 展开更多
关键词 Pinus patula Thinning and pruning Diameter growth Height growth VOLUME
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Improved adaptive pruning algorithm for least squares support vector regression 被引量:4
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作者 Runpeng Gao Ye San 《Journal of Systems Engineering and Electronics》 SCIE EI CSCD 2012年第3期438-444,共7页
As the solutions of the least squares support vector regression machine (LS-SVRM) are not sparse, it leads to slow prediction speed and limits its applications. The defects of the ex- isting adaptive pruning algorit... As the solutions of the least squares support vector regression machine (LS-SVRM) are not sparse, it leads to slow prediction speed and limits its applications. The defects of the ex- isting adaptive pruning algorithm for LS-SVRM are that the training speed is slow, and the generalization performance is not satis- factory, especially for large scale problems. Hence an improved algorithm is proposed. In order to accelerate the training speed, the pruned data point and fast leave-one-out error are employed to validate the temporary model obtained after decremental learning. The novel objective function in the termination condition which in- volves the whole constraints generated by all training data points and three pruning strategies are employed to improve the generali- zation performance. The effectiveness of the proposed algorithm is tested on six benchmark datasets. The sparse LS-SVRM model has a faster training speed and better generalization performance. 展开更多
关键词 least squares support vector regression machine (LS- SVRM) pruning leave-one-out (LOO) error incremental learning decremental learning.
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