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高光谱预处理方法与多模型在分类判别中的对比研究

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光谱学与光谱分析 2025年第1期45卷 125-132页

作者：居雷于洁吴炎淼李丽卢天丁亚萍束茹欣上海烟草集团有限责任公司技术中心上海200082 上海大学化学系上海200444 上海数之微信息科技有限公司上海200444

高光谱技术能够快速、无损地获取丰富的信息,在植物研究和监测中已成为一种广泛应用的工具。茄科植物作为一种重要的经济农作物,与高光谱技术结合进行研究具有巨大的应用潜力。本研究采用高光谱技术对茄科植物的初烤后不同部位叶片进行... 详细信息

高光谱技术能够快速、无损地获取丰富的信息,在植物研究和监测中已成为一种广泛应用的工具。茄科植物作为一种重要的经济农作物,与高光谱技术结合进行研究具有巨大的应用潜力。本研究采用高光谱技术对茄科植物的初烤后不同部位叶片进行分类研究。采用Field Spec 3光谱辐射仪对293份不同部位的茄科植物粉末样本进行高光谱采样,采用S-G平滑以及一阶导数和二阶导数的方法对数据进行预处理,用于信息增强和去除噪声,并通过偏最小二乘法对数据进行降维,以减少冗余特征。基于降维数据,采样支持向量机、逻辑回归、K近邻、决策树、随机森林和梯度提升决策树这六种机器学习算法建立分类模型。结果显示,在分类任务中,经过一阶导数处理后,支持向量机模型最佳,在训练集和测试集上分别实现了100.0%和84.7%的准确率。经网格参数优化后确定最优参数为:最大深度不限制,最小样本分割数为4,估计器数量为200。参数优化后五折交叉验证准确率为88.1%,训练集准确率为100%,测试集准确率为86.4%。研究结果表明,预处理方法结合降维方法能够增强数据信息使得分类模型能够更好地捕捉茄科植物样本的特征。该研究对于快速、准确、无损地区分茄科植物的部位具有重要意义。

关键词：高光谱部位分类机器学习

A review of cryogenic power generation cycles with liquefied natural gas cold energy utilization

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Frontiers in Energy 2016年第3期10卷 363-374页

作者： Feier XUE yu CHEN Yonglin ju Institute of Refrigeration and Cryogenics Shanghai Jiao Tong University Shanghai 200240 China College of Mechanical Engineering Shanghai University of Engineering Science Shanghai 201620 China

Liquefied natural gas （LNG）, an increasingly widely applied clean fuel, releases a large number of cold energy in its regasification process. In the present paper, the existing power generation cycles utilizing LNG cold energy are introduced and summarized. The direction of cycle improvement can be divided into the key factors affecting basic power generation cycles and the structural enhancement of cycles utilizing LNG cold energy. The former includes the effects of LNG-side parameters, working fluids, and inlet and outlet thermodynamic parameters of equipment, while the latter is based on Rankine cycle, Brayton cycle, Kalina cycle and their compound cycles. In the present paper, the diversities of cryogenic power generation cycles utilizing LNG cold energy are discussed and analyzed. It is pointed out that further researches should focus on the selection and component matching of organic mixed working fluids and the combination of process simulation and experi- mental investigation, etc.

关键词： liquefied natural gas (LNG) cold energy,power generation cycle Rankine cycle compound cycle

Investigation on Relationships among Deformation,Texture and Properties of TA16 Alloy Tube

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Journal of Materials Science & Technology 2001年第1期17卷 151-152页

作者： Weilu WU Zhentao yu ju DENG Northwest institute for Nonferrous Metal Research P.O.Box 51 Xi’an 710016China

The relationships among the deformation, texture and properties of TA16 alloy tube were investigated, an optimum processing parameter was obtained. High Q (the ratio of reduction of diameter to reduction of wall thickness) values increase tensile, flaring properties and reduce flattening; high Q values increase tensile strength, flattening, flaring. and decrease tensile elonga. tion. The main circular textures of rolling tubes are basal (0001) and pyramidal {1015}, {1014}, {1013} etc., and the main axial textures are prism {1010} and pyramidal {1120}, {2131}, {2021} etc. under different Q and E values. There are greater changes in the grain size under different E values, compared with that under different Q values.

关键词： processing parameter tensile strength wall thickness grain size

Efficacy of active compounds of Chanqin granules on airway neurogenic inflammation induced by PM2.5 in vivo

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Journal of Traditional Chinese Medicine 2020年第5期40卷 792-802页

作者： ju Ya Shen Ruobing yu Xiaoping Department of Traditional Chinese Medicine Shuguang HospitalShanghai University of Traditional Chinese MedicineShanghai 200120China

OBJECTIVE:To investigate the efficacy of active compounds of Chanqin(CQ)granules on PM2.5-induced airway neurogenic inflammation in vivo,and to elucidate the underlying mechanisms of ***:The Traditional Chinese Medicine systems pharmacology(TCMSP)database was searched,and the results were combined with oral bioavailability and drug analysis to identify the compounds in CQ *** pharmacophore modeling approach was used to predict the compound targets,and the diseases corresponding to the targets were obtained by searching the therapeutic target database(TTD),pharmacogenomics knowledgebase(Pharm GKB)and Drug Bank *** software was used to construct the network pharmacological charts for Component-Target and Target-Disease interactions of the CQ ***,the mechanisms of action and effectiveness of CQ granules for the treatment of PM2.5-induced airway neurogenic inflammation were ***:A total of 195 compounds and 171 targets were obtained from the analyses.A total of569 corresponding diseases were identified for these ***-target and target-disease networks were *** possible mechanisms and effective components in CQ granules for treating airway neurogenic inflammation were ***,kaempferol and isorhamnetin,beta-sitosterol and sitosterol,which are typically found in the formulation,have extensive pharmacological activities,including anti-inflammatory,antioxidant and antiviral actions and neuroprotective *** these targets,androgen receptor,estrogen receptor,prostaglandin G/H synthase 2,and inducible nitric oxide synthase play important pathological roles,including the induction of neurogenic *** granules may have therapeutic effectiveness for numerous diseases in addition to respiratory diseases,including neoplasms,digestive system diseases,cardiovascular diseases,respiratory tract diseases and nervous system *** vivo,CQ granules are effective in trea

关键词： Neurogenic inflammation Pharmacology Neuropeptides MAP kinase signaling system Ganglia,spinal PM2.5 Chan Qin granules

Quick-homogeneous Corrosion of Ti-2A1-2.5Zr Alloy in High-temperature and High-pressure Water Steam

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Journal of Materials Science & Technology 2001年第1期17卷 43-44页

作者： Lin YANG Zhentao yu ju DENG Northwest institute for Nonferrous Metal Research Xi’an 710016China

The corrosion behavior of Ti-2A1-2.5Zr alloy with 5 alloy contents and 5 surface states were studied in water steam at 400℃, 10.3 MPa for 72 h. The weight-increments of all samples are under 4 mg/dm2, better than Zr and Zr-alloy. or-Ti is oxidized into anatase-type TiO2 preferentially. The corrosion resistance is improved by adding Al element or pre-oxidizing treatment, the latter is more effective relatively.

关键词： corrosion resistance corrosion behavior surface states Al element

Anti-HBV hairpin ribozyme-mediated cleavage of target RNA in vitro

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World Journal of Gastroenterology 2002年第1期8卷 91-94页

作者： yu-HuSong ju-ShengLin 等 InstituteofLiverDiseases TongjiHospitalTongjiMedicalCollegeHuazhongUniversityofScienceandTechologyWuhan430030HubeiProvinceChina InstituteofLiverDiseases TongjiHospitalTongjiMedicalCollegeHuazho

AIM: To study the preparation and cleavage activity of HpRzdirected against the transcript of HBV core gene in ***: HpRz gene designed by computer targeting thetranscript of HBV core gene was cloned into the vector p1 .5between 5'-cis-Rz and 3'-cis-Rz. 32p-labeled HpRz transcriptproved whether the vector fit for the preparation of hairpinribozyme in vitro. 32p-labeled pKC transcript containing HBVcore region as target-RNA was transcribed using T7 RNApolymerase and purified by denaturing PAGE. Cold HpRztranscript was incubated with 32p-labeled target-RNAs underdifferent conditions and radioautographed after denaturingpolyacrylamide gel ***: HpRz has the specific ability of cleavage of target-RNA at 37℃ and 12 mM MgCL2. Km = 26.31nmol/L, Kcat = 0.18/min. These results revealed that the design of HpRz ***: HpRz prepared in this study possessesspecific catalytic activity from the identification of cleavageactivity. These results indicate that hairpin ribozyme mayintracellularly inhibit the replication of HBV, therefore it maybecome a novel potent weapon for the treatment of hepatitisB.

关键词：乙型肝炎核酶 RNA分裂靶细胞抗病毒机制

Climate effects of the GlobeLand30 land cover dataset on the Beijing Climate Center climate model simulations

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Science China Earth Sciences 2016年第9期59卷 1754-1764页

作者： SHI XueLi NIE SuPing ju WeiMin yu Le National Climate Center Beijing 100081 China International Institute for Earth System Science (ESSI) Nanjing University Nanjing 210093 China Ministry of Education Key Laboratory for Earth System Modeling Center for Earth System Science Tsinghua University Beijing 100084 China Joint Center for Global Change Studies Beijing 100875 China

Land cover is one of the most basic input elements of land surface and climate models. Currently, the direct and indirect effects of land cover data on climate and climate change are receiving increasing attentions. In this study, a high resolution(30 m) global land cover dataset(Globe Land30) produced by Chinese scientists was, for the first time, used in the Beijing Climate Center Climate System Model(BCC_CSM) to assess the influences of land cover dataset on land surface and climate simulations. A two-step strategy was designed to use the Globe Land30 data in the model. First, the Globe Land30 data were merged with other satellite remote sensing and climate datasets to regenerate plant functional type(PFT) data fitted for the BCC_CSM. Second, the up-scaling based on an area-weighted approach was used to aggregate the fine-resolution Globe Land30 land cover type and area percentage with the coarser model grid resolutions globally. The Globe Land30-based and the BCC_CSM-based land cover data had generally consistent spatial distribution features, but there were some differences between them. The simulation results of the different land cover type dataset change experiments showed that effects of the new PFT data were larger than those of the new glaciers and water bodies(lakes and wetlands). The maximum value was attained when dataset of all land cover types were changed. The positive bias of precipitation in the mid-high latitude of the northern hemisphere and the negative bias in the Amazon, as well as the negative bias of air temperature in part of the southern hemisphere, were reduced when the Globe Land30-based data were used in the BCC_CSM atmosphere model. The results suggest that the Globe Land30 data are suitable for use in the BCC_CSM component models and can improve the performance of the land and atmosphere simulations.

关键词： Land cover Climate model Application strategy Numerical simulation Air temperature Precipitation

Vertically aligned two-dimensional materials-based thick electrodes for scalable energy storage systems

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Nano Research 2021年第10期14卷 3562-3575页

作者： Zhengyu ju Xiao Zhang Jingyi Wu Guihua yu Materials Science and Engineering Program Texas Materials InstituteThe University of Texas at AustinAustinTexas 78712USA

Together with the blooming of portable smart devices and electric vehicles in the last decade,electrochemical energy storage(EES)devices capable of high-energy and high-power storage are urgently ***-dimensional(2D)materials,benefiting from the short solid-state diffusion distance,are well recognized to possess excellent electrochemical ***,liquid diffusion,the rate-determining process in thick electrodes,is notably slow in 2D materials-based electrodes stemming from their stacking during electrode processing,which considerably limits their applications for high energy *** fully exploit intrinsic advantages of 2D materials for scalable energy storage devices,this review summarizes several important strategies,ranging from assembly to template methods,to fabricate vertically aligned 2D materials-based *** further discuss the advantages and challenges of these methods in terms of key features of thick electrodes and illustrate the design principles for high-energy/power devices.

关键词： two-dimensional materials energy storage alignment assembly high energy/power

Prevention of self-harm through early detection of depression among the elderly with permanent pacemaker:a case report

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Journal of Geriatric Cardiology 2021年第4期18卷 312-315页

作者： yu-Wei CHANG ju-Yi CHEN Division of Cardiology Department of Internal MedicineNational Cheng Kung University HospitalCollege of MedicineNational Cheng Kung UniversityTaiwanChina

There is consensus regarding the efficacy and safety of permanent pacemakers(PPM) and other cardiac implantable electronic devices. These devices improve the quality of life by reliving symptoms of bradycardia including dizziness, fatigue and exercise intolerance. The decision to implant a PPM is often made at the time of the initial encounter with the patient, such as when symptomatic bradyarrhythmia is first diagnosed.

关键词： permanent cardiac implant