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Journal of Forestry Research 2023年第1期34卷 167-176页

作者： Krunoslav Sever saša Bogdan ŽeljkoŠkvorc Faculty of Forestry and Wood Technology University of ZagrebSvetošimunska 2510000 ZagrebCroatia

The objective was to examine the effects of optimal leaf nitrogen levels>2.0%and suboptimal levels<2.0%,nitrogen nutrition on net photo synthetic rate,stem diameter increment,height growth increment and acorn mass of pedunculate oak during 2010 in the absence of drought stress and during 2011 under the impact of moderate drought *** to the results,moderate drought stress significantly reduced net photo synthetic rate,stem diameter increment and height growth increment,while acorn mass was not *** nitrogen nutrition significantly reduced the net photo synthetic rate and stem diameter increment only in the wet year,acorn mass in both wet and dry years,while height growth increment was not significantly reduced by suboptimal nitrogen nutrition in either *** results indicate that optimal nitrogen levels can stimulate photo synthetic rate and stem diameter increment of pedunculate oak only in the absence of moderate drought ***,the results show that moderate drought stress is a more dominant stressor for photosynthesis and growth of pedunculate oak than suboptimal nitrogen nutrition,while for acorn development,it is the more dominant stressor.

关键词： Quercus robur L. Drought stress Net photosynthic rate Stem diameter increment Height growth increment Acorn mass

一种基于DTW-DP-GMM的工业机器人轨迹学习策略

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天津大学学报（自然科学与工程技术版） 2025年第1期58卷 68-80页

作者：肖洒陈旭阳叶锦华吴海彬福州大学机械工程及自动化学院福州350108 福建省特种智能装备安全与测控重点实验室福州350108

针对机器人示教编程过程中使用高斯混合模型(GMM)规划运动轨迹时存在的高斯分布个数难以选择、复现轨迹精度较低等问题,提出了一种复合的机器人运动轨迹学习策略.该策略包含动态时间规整(DTW)算法、高斯混合模型与道格拉斯-普克(DP)算法... 详细信息

针对机器人示教编程过程中使用高斯混合模型(GMM)规划运动轨迹时存在的高斯分布个数难以选择、复现轨迹精度较低等问题,提出了一种复合的机器人运动轨迹学习策略.该策略包含动态时间规整(DTW)算法、高斯混合模型与道格拉斯-普克(DP)算法.首先,针对示教过程中采集的多条轨迹在时间长度上存在差异的问题,采用DTW算法来统一示教轨迹在时域上的变化.其次,使用GMM算法对示教轨迹的特征进行提取,并利用高斯混合回归(GMR)算法将其重构为复现轨迹.在这个过程中采用DP算法来预估GMM算法的关键参数高斯分布的数量,与传统方法相比,能够简单直观地得到相对准确的参数值.利用DP算法对复现轨迹的数据点进行稀疏化并优化,不仅确保了机器人最终运动轨迹的精度,而且大幅减少了最终轨迹数据点的数量.最后,进行了不同形状的模拟焊接轨迹学习规划实验.结果表明:经由DTW对齐后的示教轨迹具有更加明显的运动特征,经过GMM-GMR学习输出的复现轨迹具有良好的表征结果;在使用GMM-GMR算法学习示教轨迹的过程中,采用DP算法可以有效预估高斯分布个数;经过DP算法稀疏化并优化的最终轨迹的平均位置误差均在0.500 mm以内,其最大误差可以控制在0.800 mm以内,可以满足焊接轨迹规划的精度要求,验证了该策略的有效性和优越性.

关键词：工业机器人示教编程高斯混合模型道格拉斯-普克算法动态时间规整轨迹复现

Ecoregional height-diameter models for Scots pine in Turkiye

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Journal of Forestry Research 2024年第6期35卷 49-61页

作者： Fadime sağlam Oytun Emre sakici Department of Forest Engineering Faculty of ForestryKastamonu University37150 KastamonuTurkey

Ecoregion-based height-diameter models were developed in the present study for Scots pine(Pinus sylves-tris L.)stands in Turkiye and included several ecological factors derived from a pre-existing ecoregional classification *** data were obtained from 2831 sample trees in 292 sample *** generalized height–diameter models were developed,and the best model(HD10)was selected according to statistical ***,nonlinear mixed-effects modeling was applied to the best *** R2 for the generalized height‒diameter model(Richards function)modified by Sharma and Parton is 0.951,and the final model included number of trees,dominant height,and diameter at breast height,with a random parameter associated with each ecoregion attached to the inverse of the mean basal *** full model predictions using the nonlinear mixed-effects model and the reduced model(HD10)predictions were compared using the nonlinear sum of extra squares test,which revealed significant differences between ecore-gions;ecoregion-based height–diameter models were thus found to be suitable to *** addition,using these models in appropriate ecoregions was very important for achieving reliable predictions with low prediction errors.

关键词： Tree height Nonlinear mixed-effects modelling Nonlinear sum of extra squares method Ecoregion Scots pine

Practices of backuping homomorphically encrypted databases

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Frontiers of Computer Science 2019年第2期13卷 220-230页

作者： sa WANG Yiwen SHAO Yungang BAO SKL Computer Architecture Institute of Computing Technology Chinese Academy of Sciences Beijing 100190 China University of Chinese Academy of Sciences Beijing 100049 China

Ideal homomorphic encryption is theoretically achievable but impractical in reality due to tremendous computing overhead. Homomorphically encrypted databases, such as CryptDB, leverage replication with partially homomorphic encryption schemes to support different SQL queries over encrypted data directly. These databases reach a balance between security and efficiency, but incur considerable storage overhead, especially when making backups. Unfortunately, general data compression techniques relying on data similarity exhibit inefficiency on encrypted data. We present CryptZip, a backup and recovery system that could highly reduce the backup storage cost of encrypted databases. The key idea is to leverage the metadata information of encryption schemes and selectively backup one or several columns among semantically redundant columns. The experimental results show that CryptZip could reduce up to 90.5% backup storage cost on TPC-C benchmark.

关键词： homomorphic encryption security deduplication

A location-based fog computing optimization of energy management in smart buildings:DEVS modeling and design of connected objects

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Frontiers of Computer Science 2023年第2期17卷 179-195页

作者： Abdelfettah MAATOUG Ghalem BELALEM saïd MAHMOUDI Computer Science Department Faculty of Exact and Applied SciencesUniversity of Oran 1 Ahmed Ben BellaOran 31000Algeria Science and Technology Department Faculty of Science and TechnologyUniversity of TIARETTiaret 14000Algeria Computer Science Department Faculty of EngineeringUniversity of MonsMons 7000Belgium

Nowadays,smart buildings rely on Internet of things(loT)technology derived from the cloud and fog computing paradigms to coordinate and collaborate between connected *** is characterized by low latency with a wider spread and geographically distributed nodes to support mobility,real-time interaction,and location-based *** provide optimum quality of user life in moderm buildings,we rely on a holistic Framework,designed in a way that decreases latency and improves energy saving and services efficiency with different *** EVent system Specification(DEVS)is a formalism used to describe simulation models in a modular *** this work,the sub-models of connected objects in the building are accurately and independently designed,and after installing them together,we easily get an integrated model which is subject to the fog computing *** results show that this new approach significantly,improves energy efficiency of buildings and reduces ***,with DEVS,we can easily add or remove sub-models to or from the overall model,allowing us to continually improve our designs.

关键词： smart building energy consumption IoT fog computing Framework DEVS simulation models

Synthesis,Structures,and Fluorescence Property of a Novel Heterometallic Complex Constructed by Imidazole

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Chinese Journal of Structural Chemistry 2020年第5期39卷 942-948页

作者： LI sa-Ying Department of Chemistry Chemical Engineering Shaanxi Xueqian Normal UniversityXi'an 710100China

A novel heterometallic complex constructed by imidazole ligand,CoZn(C3N2H3)4(1),has been synthesized under hydrothermal *** 1 was characterized by IR spectra,thermal analysis,powder X-ray diffraction and single-crystal X-ray ***-crystal X-ray diffraction studies reveals that compound 1 is in the tetragonal system,space group I41cd with a=23.4371(5),b=23.4371(5),c=12.4430(7)?,V=6834.9(4)?3,Z=16,C12H12CoN8Zn,Mr=392.60,Dc=1.526 g/cm^3,F(000)=3152,μ=2.381 mm–1,R=0.0323 and w R=*** CoZn(C3N2H3)4 is one-dimensional heterometallic molecular chains,which are further extended into a 3D open ***,the solid-state fluorescence property of the complex has also been investigated at room temperature.

关键词： heterometallic complex crystal structure fluorescence property

TRANSVERSE ENERGY DISTRIBUTION FOR REACTION 32S+NUCLEUS AT 200A GeV

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Chinese Physics Letters 1990年第4期7卷 170-173页

作者： LU Zhongdao sa Benhao Institute of Atomic Energy Beijing 102413

By using multiple collision model the transverse energy distributions in reactions of ^(32)S+ nuclides at 200A GeV are *** geometry effects both for projectile and target are discussed.

关键词： transverse collision geometry

Artificial intelligence-based predictive model of nanoscale friction using experimental data

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Friction 2021年第6期9卷 1726-1748页

作者： Marko PERČIĆ saša ZELENIKA Igor MEZIĆ University of Rijeka Faculty of Engineering51000 RijekaCroatia University of Rijeka Centre for Micro-and Nanosciences and Technologies&Center for Artificial Intelligence and Cybersecurity51000 RijekaCroatia University of California santa Barbara Department of Mechanical EngineeringSanta BarbaraCA 93105USA

A recent systematic experimental characterisation of technological thin films,based on elaborated design of experiments as well as probe calibration and correction procedures,allowed for the first time the determination of nanoscale friction under the concurrent influence of several process parameters,comprising normal forces,sliding velocities,and temperature,thus providing an indication of the intricate correlations induced by their interactions and mutual *** created the preconditions to undertake in this work an effort to model friction in the nanometric domain with the goal of overcoming the limitations of currently available models in ascertaining the effects of the physicochemical processes and phenomena involved in nanoscale *** to the stochastic nature of nanoscale friction and the relatively sparse available experimental data,meta-modelling tools fail,however,at predicting the factual *** on the acquired experimental data,data mining,incorporating various state-of-the-art machine learning(ML)numerical regression algorithms,is therefore *** results of the numerical analyses are assessed on an unseen test dataset via a comparative statistical *** is therefore shown that the black box ML methods provide effective predictions of the studied correlations with rather good accuracy levels,but the intrinsic nature of such algorithms prevents their usage in most practical *** programming-based artificial intelligence(AI)methods are consequently finally *** the marked complexity of the analysed phenomena and the inherent dispersion of the measurements,the developed AI-based symbolic regression models allow attaining an excellent predictive performance with the respective prediction accuracy,depending on the sample type,between 72%and 91%,allowing also to attain an extremely simple functional description of the multidimensional dependence of nanoscale friction on the studied variable process param

关键词： nanoscale friction thin films data mining machine learning(ML) predictive artificial intelligence(AI)-based model

Rapid on-site evaluation of endoscopic-ultrasound-guided fine-needle aspiration diagnosis of pancreatic masses

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World Journal of Gastroenterology 2014年第28期20卷 9451-9457页

作者： Julio Iglesias-Garcia Jose Lario-Noia ihab Abdulkader J Enrique Domínguez-Muoz Department of Gastroenterology and Hepatology Foundation for Research in Digestive DiseasesUniversity Hospital of Santiago de Compostela Department of Pathology University Hospital of Santiago de Compostela

Endoscopic ultrasound (EUS) has become an essential tool for the study of pancreatic diseases. Specifically, EUS plays a pivotal role evaluating patients with a known or suspected pancreatic mass. In this setting, differential diagnosis remains a clinical challenge. EUS-guided fine-needle aspiration (FNA) and fine-needle biopsy (FNB) have been proven to be safe and useful tools in this setting. EUS-guided FNA and FNB, by obtaining cytological and/or histological samples, are able to diagnose pancreatic lesions with high sensitivity and specificity. In this context, several methodological features, trying to increase the diagnostic yield of EUS-guided FNA and FNB, have been evaluated. In this review, we focus on the role of rapid on-site evaluation (ROSE). From data reported in the literature, ROSE may increase diagnostic yield of EUS-FNA specimens by 10%-30%, and thus, diagnostic accuracy. However, we should point out that many recent studies have reported adequacy rates of > 90% without ROSE, indicating that, perhaps, at high-volume centers, ROSE may not be indispensable to achieve excellent results. The use of ROSE can be considered important during the learning curve of EUS-FNA, and also in hospital with diagnostic accuracy rates < 90%.

关键词： Endoscopic-ultrasound-guided fine-needle aspiration Rapid on-site evaluation Solid pancreatic tumors Diagnostic accuracy

Preparation of Novel Composite from Natural Rubber, Bagasse and Plaster

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Journal of Chemistry and Chemical Engineering 2010年第8期4卷 56-62页

作者： sa-ad Riyajan Isara Intharit Suthikiat Thaiprasansup Pramuan Tangboriboonrat Department of Materials Science and Technology Bioplastics Research Unit Faculty of Science Prince of Songkla University Hat Yai Songkhla 90112 Thailand Department of Faculty of Science Mahidol University Bangkok 10400 Thailand

The sugar cane bagasse was treated with chemical treatment including sodium hydroxide and silane. The characterization of the modified bagasse was achieved with Fourier transform infrared spectroscopy （FTIR）, and scaning electron microscopy （SEM）. Results showed that the presence Si-CH3 group occurred on bagasse surface after chemical modification. In addition, the roughness of the modified bagasse was higher than that of unmodified bagasse due to chemical modification from sodium hydroxide. Two polymer composite types, namely （1） natural rubber NR/sugar cane bagasse and （2） NR/plaster via two-roll mill method, were prepared. The optimum cure （t90） and torque of the NR/plaster increased with increasing plaster loading in composite. In case of NR/bagasse, the tgo of this sample decreased as a function of sugar cane bagasse while torque of this sample increased with increasing sugar cane bagasse. The modulus of the resulting composite increased with increasing both plaster and sugar cane bagasse, but the tensile strength and elongation at break of the composite decreased as a function of both piaster and sugar cane bagasse in composite.

关键词： Natural rubber composite bagasse plaster chemical modification.