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Developing Weibull-based diameter distributions for the major coniferous species in Heilongjiang Province,China

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Journal of Forestry Research 2023年第6期34卷 1803-1815页

作者： Qila sa Xingji Jin Timo Pukkala Fengri Li Key Laboratory of Sustainable Forest Ecosystem Management Ministry of EducationNortheast Forestry UniversityHarbin 150040People’s Republic of China university of Eastern Finland 80101 JoensuuFinland

Diameter distribution models play an important role in forest inventories,growth prediction,and *** Weibull probability density function is widely used in *** a number of methods have been proposed to predict or recover the Weibull distribution,their applicability and predictive performance for the major tree species of China remain to be *** in sample plots of three even-aged coniferous species(Larix olgensis,Pinus sylvestris and Pinus koraiensis)were measured both in un-thinned and thinned stands to develop parameter prediction models for the Weibull probability density *** least squares(OLS)and maximum likelihood regression(MLER),as well as cumulative distribution function regression(CDFR)were used,and their performance *** results show that MLER and CDFR were better than OLS in predicting diameter distributions of tree *** produced the best results in terms of fitting *** on the error statistics calculated for different age groups,CDFR was considered the most suitable method for developing prediction models for Weibull parameters in coniferous plantations.

关键词： Parameter prediction Maximum likelihood regression Cumulative distribution function regression

Sino -u .S .Relations in Retrospect and Prospect——In Commemoration of the 25th Anniversary for the Establishment of Diplomatic Relations Between the PRC and the u.S.A

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和平与发展 2004年第2期 60-64页

作者： sa Benwang

Supertetragonal BaZrS_(3):A promising perovskite sulphide with giant ferroelectricity and low band gap

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Science China(Physics,Mechanics & Astronomy) 2024年第8期67卷 126-133页

作者： Menglu Li sa Zhang Chenhan Liu Xiaotao Zu Liang Qiao Haiyan Xiao School of Physics University of Electronic Science and Technology of ChinaChengdu 611731China College of Mathematics and Physics Chengdu University of TechnologyChengdu 610059China Micro-and Nano-scale Thermal Measurement and Thermal Management Laboratory Ministry of Education Key Laboratory of Numerical Simulation of Large-Scale Complex SystemsSchool of Energy and Mechanical EngineeringNanjing Normal UniversityNanjing 210023China

Over the past century,ferroelectricity has offered exciting opportunities for fundamental research and device ***,most of the discovered excellent ferroelectrics are oxide materials with large band gaps,limiting their potential for optoelectronics *** using first-principles calculations we identify a new narrow-gap ferroelectric beyond oxides,i.e.,ferroelectric perovskite sulphide BaZrS_(3).under large compressive strains,BaZrS_(3)can be stabilized into a unique supertetragonal phase with an extraordinary polarization of 67.16μC/cm^(2),which is even stronger than that of conventional oxide ***,the supertetragonal BaZrS_(3)exhibits a direct narrow band gap of 1.2 eV and excellent electronic *** on the chemical bonding analysis,we attribute the formation of supertetragonal phase to charge re-ordering in which theπbond overlap along the long〈Zr-S〉bond completely vanishes and the antibonding states of theσbond appear below the Fermi *** work provides a conceptual strategy for designing new ferroelectrics for electronic and photovoltaic applications.

关键词： supertetragonal phase perovskite sulphide ferroelectricity

A Throughput-Aware Joint Vehicle Route and Access Network Selection Approach Based on SMDP

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China Communications 2020年第5期17卷 243-265页

作者： Jiandong Xie sa Xiao Ying-Chang Liang Li Wang Jun Fang National Key Laboratory of Science and Technology on Communications University of Electronic Science and Technology of ChinaChengdu 116024China Center for Intelligent Networking and Communications(CINC) University of Electronic Science and Technology of China(UESTC)Chengdu 611731China Research and Development Center Huawei TechnologiesStockholm 16494Sweden

In intelligent transportation system(ITS), the interworking of vehicular networks(VN) and cellular networks(CN) is proposed to provide high-data-rate services to vehicles. As the network access quality for CN and VN is location related, mobile data offloading(MDO), which dynamically selects access networks for vehicles, should be considered with vehicle route planning to further improve the wireless data throughput of individual vehicles and to enhance the performance of the entire ITS. In this paper, we investigate joint MDO and route selection for an individual vehicle in a metropolitan scenario. We aim to improve the throughput of the target vehicle while guaranteeing its transportation efficiency requirements in terms of traveling time and distance. To achieve this objective, we first formulate the joint route and access network selection problem as a semi-Markov decision process(SMDP). Then we propose an optimal algorithm to calculate its optimal policy. To further reduce the computation complexity, we derive a suboptimal algorithm which reduces the action space. Simulation results demonstrate that the proposed optimal algorithm significantly outperforms the existing work in total throughput and the late arrival ***, the heuristic algorithm is able to substantially reduce the computation time with only slight performance degradation.

关键词： mobile data offloading network selection route selection semi-Markov decision process vehicular network

Rapidity,Transverse Mass Distributions and Nuclear Stopping in(14.6 AGeV/c)Si+A u Reactions

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Chinese Physics Letters 1993年第8期10卷 468-471页

作者： WANG Zhongqi sa Benhao Lu Zhongda ZHANG Xiaoze SONG Guang ZHENG Yuming CCAST(World Lab.) Beijing 100080 China Institute of Atomic Energy Beijing 102413(mailing address)

The experimental data of proton and pion rapidity distributions and proton transverse mass distribution in rcaction of(14.6AGeV/c)Si+Au are compared with a simple relativistic hadronic cascade *** theoretical results ... 详细信息

关键词： energy statement

High-precision geochronology of Mesozoic magmatism in Macao,Southeast China:Evidence for multistage granite emplacement

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Geoscience Frontiers 2020年第1期11卷 243-263页

作者： Pedro Quelhas Agata Alveirinho Dias Joao Mata Donald Wayne Davis Maria Luísa Ribeiro Institute of Science and Environment University of Saint JosephMacaoChina Instituto Dom Luiz Faculdade de CiênciasUniversidade de LisboaLisboaPortugal Jack satterly Geochronology Laboratory Department of Earth SciencesUniversity of TorontoTorontoOntCanada Laboratório Nacional de Engenharia e Geologia LisboaPortugal

Six new high precision u-Pb zircon ID-TIMS ages plus thirteen in situ high spatial resolution u-Pb zircon LA-MC-ICPMS ages are reported from Jurassic plutonic(metaluminous to weakly peraluminous biotite granites)and Jurassic to Cretaceous hypabyssal(dacites)rocks from *** its relatively small area(~30 km^2),the new ages tightly constrain the Macao granitic magmatism to two periods ranging from 164.5±0.6 Ma to 162.9±0.7 Ma and 156.6±0.2 Ma to 155.5±0.8 Ma,separated by ca.6 *** zircons point to the existence of a basement with ages up to Paleo-Proterozoic and late Archean in the *** addition,younger dacitic rocks were dated at 150.6±0.6 Ma andu-Pb zircon ages and whole-rock REE data of Macao granites indicate that the first pulse is also represented in Hong Kong and Southeast(SE)China,while magmatism with the chemical characteristics of the second pulse seems to not be represented outside *** two granitic magmatic pulses have distinct mineralogical and geochemical features that support their discrete nature rather than a continuum of comagmatic activity and suggest that the Macao granitic suite was incrementally assembled during a period of ca.9 Ma,a hypothesis also extendable to the neighboring Hong Kong region for a time lapse of ca.24 *** Macao,the transition from granitic magmatism(Middle to upper Jurassic)to the younger dacite dykes(upper Jurassic to Lower Cretaceous)most likely corresponds to a change in the regional tectonic setting,from an extensional regime related with foundering of the subducting paleoPacific plate during the Early Yanshanian period to the reestablishment of a normal subduction system in SE China during the Late Yanshanian period.

关键词： Granites u-Pb geochronology Zircon Jurassic Yanshanian orogeny Macao

Nucleon Finite Volume Effect and Nuclear Matter Properties in a Relativistic Mean-Field Theory

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Communications in Theoretical Physics 2006年第6X期46卷 1052-1058页

作者： R. Costa A.J. santiago H. Rodrigues J. sa Borges Instituto de Fisica Universidade do Estado do Rio de Janeiro Rio de Janeiro-RJ 20559-900 Brazil Centro Federal de Educ~ao Tecnológica Rio de Janeiro Brazil

Effects of excluded volume of nucleons on nuclear matter are studied, and the nuclear properties that follow from different relativistic mean-field model parametrizations are compared. We show that, for all tested parametrizations, the resulting volume energy al and the symmetry energy J are around the acceptable values of 16 MeV and 30 MeV, and the density symmetry L is around 100 MeV. On the other hand, models that consider only linear terms lead to incompressibility Ko much higher than expected. For most parameter sets there exists a critical point （pc, δc）, where the minimum and the maximum of the equation of state are coincident and the incompressibility equals zero. This critical point depends on the excluded volume parameter r. If this parameter is larger than 0.5 fm, there is no critical point and the pure neutron matter is predicted to be bound. The maximum value for neutron star mass is 1.85M⊙, which is in agreement with the mass of the heaviest observed neutron star 4u0900-40 and corresponds to r = 0.72 fm. We also show that the light neutron star mass （1.2M⊙） is obtained for r ≌ 0.9 fro.

关键词： nuclear matter relativistic models nuclear matter aspects of neutron stars

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暴发性肝衰竭小鼠细菌侵袭肠黏膜方式的研究

中华肝脏病杂志 2011年第3期19卷 214-217页

作者：宋红丽吕飒刘沛中国医科大学附属第一医院传染科沈阳110001

目的通过研究细菌侵袭肠黏膜屏障的方式，探讨暴发性肝衰竭（FHF）并发自发性腹膜炎（SBP）的机制。方法取240只雄性BALB／c小鼠，分为等渗盐水（NS）组（40只）、脂多糖（LPS）组（40只）、氨基半乳糖（GaIN）组（40只）、FHF模型组（... 详细信息

目的通过研究细菌侵袭肠黏膜屏障的方式，探讨暴发性肝衰竭（FHF）并发自发性腹膜炎（SBP）的机制。方法取240只雄性BALB／c小鼠，分为等渗盐水（NS）组（40只）、脂多糖（LPS）组（40只）、氨基半乳糖（GaIN）组（40只）、FHF模型组（120只）。分别腹腔注射相同体积的NS、LPS（10μg／kg）、GaIN（800mg／kg）、LPS（10μg／kg）／GalN（800mg／kg）。注射处理后，分别于2、6、9、12h和24h处死小鼠（每个时间点处死8只小鼠）。实验小鼠均在相应时间点摘取眼球，留取血清，并断头处死动物，留肝脏及大肠组织标本。用全自动生物化学分析仪检测ALT；对肝组织和大肠组织进行HE染色检测；透射电镜观察大肠黏膜超微结构及细菌侵袭肠黏膜的方式。用SPSS13．0统计软件进行数据分析，两组间ALT水平的分析采用Mann—Whitneyu检验。结果FHF模型组ALT水平、肝组织病理学检测结果及病死率和临床表现均符合FHF的诊断标准。4组小鼠注射处理后9h，HE染色发现大肠组织仅有轻微水肿及少量炎性细胞浸润，此时，透射电镜下观察发现FHF模型组肠上皮细胞微绒毛断裂、脱落、变短，紧密连接（TJs）不完整，细胞器变化明显，HE染色发现FHF模型组肝脏呈成片的出血性坏死，残存的肝细胞肿胀，出血坏死区见较多炎性细胞浸润，但NS组、LPS组、GaIN组肝脏组织病理形态及大肠黏膜超微结构变化不明显。FHF模型组注射处理后6～9h，细菌以胞饮的形式穿人肠壁，细菌穿入肠壁区域的肠道黏膜绒毛脱落，TJs出现断裂，注射处理后12h发现穿入的细菌以囊胞的形式存在。结论LPS（10μg／kg）／GAIN（800mg／kg）联合注射建立的FHF小鼠模型是成功的。FHF时，肠黏膜TJs的断裂可能为肠道内细菌进入肠黏膜提供了条件，TJS的断裂可能是FHF并发SBP的原因之一。

关键词：肝功能衰竭急性小鼠肠黏膜细菌

A determination of the quality of life of children and adolescents with type 1 diabetes and their parents

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International Journal of Nursing Sciences 2017年第2期4卷 94-98页

作者： Nurcan Özyazicioglu Elif Ünsal Avdal Halil saglam Department of Pediatric Nursing Faculty of Health SciencesUludag UniversityBursaTurkey Department of Internal Medicine Nursing Faculty of Health ScienceKatipÇelebi UniversityIzmirTurkey Department of Pediatrics Pediatric Endocrinology DivisionFaculty of MedicineUludag UniversityBursaTurkey

Objective: Type 1 diabetes is a chronic illness which can have a negative effect on the health care and development of children and can put their lives in danger. This descriptive study aimed to determine the quality of life and the factors affecting it of children and adolescents with type 1 diabetes using the Pediatric Quality of Life Inventory (PedsQL).Methods: The study was conducted in the Child Endocrinology unit of a university Hospital in Bursa, Turkey. Totally 64 children eight-12 years and 85 adolescents aged 13-18 with type 1 diabetes and their parents were recruited. HbA1c measurements were obtained from the records of the endocrinology clinicare, which were made once every three months, and the average of the last three measurements was taken in the study. The PedsQL was used to measure quality of life of the children and adolescents. The data was analyzed using SPSS version 20.0 and Pusing means and percentiles. Pearson's correlation analysis was used to assess the relationship between two averages. Results: Of the sub-groups on the scale, affective and school function scores were somewhat low, and social function scores were high. The quality of life scores of the children and adolescents were found to correlate with those of their parents. A negative correlation was found between HbA1c levels and adolescent quality of life, a positive correlation was found between the child's age and the quality of life of the child and parents, and a negative correlation was found between the number of children in the family and the quality of life of the child and parents. Conclusions: An evaluation of the quality of life after a diagnosis of diabetes can be used to assess the problems which may be faced by children and adolescents and to combat these problems.

关键词： Adolescent Child Diabetes mellitus Parents Pediatric quality of life inventory Quality of life