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我国3种针叶林的材积源生物量模型研建

林业科学研究 2021年第4期34卷 49-57页

作者：曾伟生国家林业和草原局调查规划设计院北京100714

[目的]林分水平的生物量模型或数表,是森林资源调查监测的必备计量工具。研建3种针叶林的材积源生物量模型,既是方法学探索,也为生产实践提供参考成果。[方法]基于我国3种主要针叶林(落叶松、油松、杉木)的3000个固定样地的实测数据,分... 详细信息

[目的]林分水平的生物量模型或数表,是森林资源调查监测的必备计量工具。研建3种针叶林的材积源生物量模型,既是方法学探索,也为生产实践提供参考成果。[方法]基于我国3种主要针叶林(落叶松、油松、杉木)的3000个固定样地的实测数据,分别利用普通回归估计、加权回归估计和分段建模方法,建立了林分水平的材积源生物量模型,并与已发表的相关模型进行了比较。[结果]建立的3种针叶林的加权回归生物量模型,其确定系数R2在0.912~0.937之间,平均预估误差MPE在0.93%~1.58%之间,总体相对误差TRE在±2.0%以内,独立样本检验的TRE在±2.6%以内;分段建模生物量模型,其确定系数R2在0.915~0.953之间,平均预估误差MPE在0.81%~1.55%之间,总体相对误差TRE在±0.3%以内,独立样本检验的TRE在±1.3%以内。用本研究数据对已发表的3种针叶林的生物量模型进行适用性检验,其总体相对误差TRE分别达到11.62%、−25.19%和−6.26%,按不同生物量等级的估计误差更大,甚至出现系统偏差,严重超出了允许误差范围。[结论]林分每公顷生物量与蓄积量呈线性相关;建立林分生物量模型,应当采用加权回归方法,并保证样本数量足够且结构合理;当一个模型难以准确估计各个等级的生物量时,可以采用分段建模方法。本研究所建3种针叶林的材积源生物量模型,预估精度高,可以在实践中推广应用。

关键词：生物量加权回归分段建模落叶松油松杉木

H∞ Robustness for Distributed Control in Autonomous Microgrids Considering Cyber Disturbances

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CSEE Journal of Power and Energy Systems 2024年第2期10卷 696-706页

作者： Ge Cao Guannan Lou wei Gu Lina sheng School of Electrical Engineering Southeast UniversityNanjing 210096China

The physical connections and logical relationships between microgrids and communication networks allow microgrids to develop into typical cyber-physical systems(CPSs).With the extensive use of open communication mechanisms,the impact of cyber disturbances in public communication networks cannot be *** this paper,a parameter optimal method for a distributed secondary controller based on the robust control theory and consensus algorithm is presented to enhance the robustness of a secondary control system under data disturbance,parameter perturbation,and time ***,a distributed secondary control strategy of microgrids is demonstrated that coordinates frequency and voltage restoration and power ***,considering the impact of cyber events on the secondary control,a distributed robust controller gain design method is proposed to satisfy the H∞ performance *** solution of the distributed robust control is transformed into a linear matrix in equation problem and latency margin is simultaneously ***,a test microgrid CPS is simulated with and without time delay to investigate the impact of cyber events on system operational states and the effectiveness and robustness of the proposed method.

关键词： Cyber disturbance cyber-physical lsystem distributed control microgrid robust H∞control

Transient Stability Analysis and Design of VSGs with Different DC-Link Voltage Controllers

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CSEE Journal of Power and Energy Systems 2024年第2期10卷 593-604页

作者： Chao Shen wei Gu Wanxing sheng Keyan Liu School of Electrical Engineering Southeast UniversityNanjingChina Power Distribution Research Department China Electric Power Research InstituteBeijing 100192China

Virtual synchronous control has been widely studied for the advantages of emulating inertia for voltage source converters (VSCs). A constant dc-link voltage is usually assumed in existing literature to estimate transient stability of virtual synchronous generators (VSGs). However, actual power supply in the dc-side of VSGs is limited and different dc-link voltage controllers are needed to achieve power balance between DC side and AC side. Addition of dc-link voltage controller has great influence on transient behavior of VSGs, which has not been investigated by previous research. To fill this gap, this paper gives insights into the effect of dc-link voltage dynamics on transient stability of VSGs. First, two typical kinds of VSGs with dc-link voltage controllers are introduced. Then, mathematical models considering dc-link dynamics are established and the effect of dc-link voltage controllers on transient synchronization stability of VSGs is revealed through equal area criterion (EAC). It is found that dc-link voltage controller would reduce stability margin of VSGs and design-oriented transient stability analysis is carried out quantitively using critical clearing time (CCT). Finally, simulation results are given to validate correctness of theoretical analysis.

关键词： DC-link voltage dynamics equal area criterion(eac) transient synchronization stability virtual synchronous generator(VSG)

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杉木相容性立木材积表系列模型研建

林业科学研究 2014年第1期27卷 6-10页

作者：曾伟生国家林业局调查规划设计院北京100714

以我国南方地区最重要的针叶树种杉木(Cunninghamia lanceolata)为研究对象,采用误差变量联立方程组方法,建立了相容性二元立木材积方程、胸径和地径一元立木材积方程、树高胸径回归模型及地径胸径回归模型。利用3种树高模型和2种地径... 详细信息

以我国南方地区最重要的针叶树种杉木(Cunninghamia lanceolata)为研究对象,采用误差变量联立方程组方法,建立了相容性二元立木材积方程、胸径和地径一元立木材积方程、树高胸径回归模型及地径胸径回归模型。利用3种树高模型和2种地径模型组合了4个相容性立木材积表系列模型联立方程组,通过6项指标进行综合评价,结果表明由最简单的树高模型和地径模型构成的相容性系列材积模型就能取得良好效果,其二元材积表、胸径一元材积表和地径一元材积表的平均预估误差分别为1.31%、3.66%和7.39%,可用于不同目的的杉木林蓄积量估计。

关键词：二元材积方程一元材积方程树高模型地径模型误差变量联立方程组相容性杉木

Nano-Bacillus Calmette-Guérin immunotherapies for improved bladder cancer treatment

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Journal of Zhejiang University-Science B(Biomedicine & Biotechnology) 2024年第7期25卷 557-567页

作者： sheng zeng Shaoqiang XING Yifei ZHANG Haifeng WANG Qian LIU Department of Urology Tianjin First Central HospitalTianjin 300192China Department of Urology First Central Clinical CollegeTianjin Medical UniversityTianjin 300192China

Cancer immunotherapy has rapidly become the fourth mainstream treatment alternative after surgery,radiotherapy,and chemotherapy,with some promising *** aims to kill tumor cells by mobilizing or stimulating cytotoxic immune ***,the clinical applications of tumor immunotherapies are limited owing to a lack of adequate delivery pathways and high ***,nanomaterials and genetic engineering have shown great potential in overcoming these limitations by protecting the delivery of antigens,activating targeted T cells,modulating the immunosuppressive tumor microenvironment,and improving the treatment *** Calmette-Gué;rin(BCG)is a live attenuated Mycobacterium bovis vaccine used to prevent tuberculosis,which was first reported to have antitumor activity in *** therapy can activate the immune system by inducing various cytokines and chemokines,and its specific immune and inflammatory responses exert antitumor *** was first used during the 1970s as an intravesical treatment agent for bladder cancer,which effectively improved immune antitumor activity and prevented tumor *** recently,nano-BCG and genetically engineered BCG have been proposed as treatment alternatives for bladder cancer due to their ability to induce stronger and more stable immune *** this study,we outline the development of nano-BCG and genetically engineered BCG for bladder cancer immunotherapy and review their potential and associated challenges.

关键词： Bladder cancer Bacillus Calmette-Gué rin vaccine Nanocarrier Genetic engineering Immunotherapy

Isotropic sintering shrinkage of 3D glass-ceramic nanolattices:backbone preforming and mechanical enhancement

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International Journal of Extreme Manufacturing 2024年第2期6卷 418-426页

作者： Nianyao Chai Yunfan Yue Xiangyu Chen Zhongle zeng sheng Li Xuewen Wang Center of Femtosecond Laser Manufacturing for Advanced Materials and Devices State Key Laboratory of Advanced Technology for Materials Synthesis and ProcessingWuhan University of TechnologyWuhan 430070People’s Republic of China National Energy Key Laboratory for New Hydrogen-Ammonia Energy Technologies Foshan Xianhu LaboratoryFoshan 528000People’s Republic of China International School of Materials Science and Engineering Wuhan University of TechnologyWuhan 430070People’s Republic of China

There is a perpetual pursuit for free-form glasses and ceramics featuring outstanding mechanical properties as well as chemical and thermal *** is a promising idea to shape inorganic materials in three-dimensional(3D)forms to reduce their weight while maintaining high mechanical properties.A popular strategy for the preparation of 3D inorganic materials is to mold the organic–inorganic hybrid photoresists into 3D micro-and nano-structures and remove the organic components by subsequent ***,due to the discrete arrangement of inorganic components in the organic-inorganic hybrid photoresists,it remains a huge challenge to attain isotropic shrinkage during ***,we demonstrate the isotropic sintering shrinkage by forming the consecutive–Si–O–Si–O–Zr–O–inorganic backbone in photoresists and fabricating 3D glass–ceramic nanolattices with enhanced mechanical *** femtosecond(fs)laser is used in two-photon polymerization(TPP)to fabricate 3D green body *** subsequent sintering at 1000℃,high-quality 3D glass–ceramic microstructures can be obtained with perfectly intact and smooth ***-suit compression experiments and finite-element simulations reveal that octahedral-truss(oct-truss)lattices possess remarkable adeptness in bearing stress concentration and maintain the structural integrity to resist rod bending,indicating that this structure is a candidate for preparing lightweight and high stiffness glass–ceramic nanolattices.3D printing of such glasses and ceramics has significant implications in a number of industrial applications,including metamaterials,microelectromechanical systems,photonic crystals,and damage-tolerant lightweight materials.

关键词： 3D printing isotropic shrinkage femtosecond laser two-photon polymerization structural glass-ceramics

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西藏天然云杉林枯损率与采伐率模型系统研究

林业科学研究 2008年第3期21卷 353-356页

作者：曾伟生国家林业局中南调查规划设计院湖南长沙410014

利用西藏自治区2006年森林资源连续清查的天然云杉林实测样地资料,通过构建非线性联合估计模型系统,研究建立了天然云杉林总消耗率、枯损率、采伐率三者一致兼容的估测模型,为西藏天然云杉林的消耗量估测提供了参考依据,也为类似模型的... 详细信息

利用西藏自治区2006年森林资源连续清查的天然云杉林实测样地资料,通过构建非线性联合估计模型系统,研究建立了天然云杉林总消耗率、枯损率、采伐率三者一致兼容的估测模型,为西藏天然云杉林的消耗量估测提供了参考依据,也为类似模型的研建提供了经验借鉴。

关键词：枯损率采伐率兼容性模型非线性联合估计模型系统建模

An unusual case of Carney triad with high level catecholamine- secreting but no existence of extra-adrenal paraganglioma

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Chinese Medical Journal 2010年第4期123卷 510-512页

作者： QIAO Gui-bin FANG Yi zeng wei-sheng PENG Li-jun HUANG Wen-jie Department of Thoracic Surgery General Hospital of Guangzhou Military Command of Chinese People's Liberation Army Guangzhou Guangdong 510010 China Department of Respiratory Medicine General Hospital of Guangzhou Military Command of Chinese People's Liberation Army Guangzhou Guangdong 510010 China

In 1977, Carney originally described the association of .gastric epithelioid leiomyosarcoma, pulmonary chondroma and extra-adrenal paraganglioma, and this unusual syndrome was subsequently called ＂Carney triad＂. At present, the diagnosis of Carney triad, requires at least two of three components-gastrointestinal stromal tumor （GIST）, pulmonary chondroma and extra-adrenal paraganglioma. Up to now, fewer than 80 cases of Carney triad have been reported worldwide.1 ^We described a case of incomplete Carney triad with multiple pulmonary chondromas and GIST. Although the patient was detected in high level secreting of catecholamine, no extra-adrenal paraganglioma has been found.

关键词： Carney triad pulmonary chondroma gastrointestinal stromal tumor paraganglioma

Sustainable and practical semi-heterogeneous photosynthesis of 5-amino-1,2,4-thiadiazoles over WS_(2)/TEMPO

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Chinese Chemical Letters 2024年第8期35卷 250-253页

作者： Jia-Cheng Hou Hong-Tao Ji Yu-Han Lu Jia-sheng Wang Yao-Dan Xu Yan-Yan zeng wei-Min He School of Chemistry and Chemical Engineering University of South ChinaHengyang 421001China

An eco-friendly and practical method for the clean preparation of 5-amino-1,2,4-thiadiazoles was *** WS_(2)as the semiconductor photocatalyst,both TEMPO and O_(2)(in air)as the redox catalysts,a variety of thiadiazoles were semi-heterogeneously formed in high to quantitative yields and could be easily collected by CPME extraction and ***,the catalytic system can be reusable for at least 5 reaction runs.

关键词： Green chemistry Thiadiazoles Heterogeneous catalyst Redox catalyst Extraction