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Search Results: 1 - 10 of 85417 matches for " 傅伟才 "
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单木生物量模型估计区域尺度生物量的不确定性
煜?,雷渊,生?
生态学报 , 2015,
Abstract: 采用系统抽样体系江西省固定样地杉木连续观测数据和生物量数据,通过montecarlo法反复模拟由单木生物量模型推算区域尺度地上生物量的过程,估计了江西省杉木地上总生物量。基于不同水平建模样本量n及不同决定系数r2的设计,分别研究了单木生物量模型参数变异性及模型残差变异性对区域尺度生物量估计不确定性的影响。研究结果表明:2009年江西省杉木地上生物量估计值为(19.84±1.27)t/hm2,不确定性占生物量估计值约6.41%。生物量估计值和不确定性值达到平稳状态所需的运算时间随建模样本量及决定系数r2的增大而减小;相对于模型参数变异性,残差变异性对不确定性的影响更小。
离心铸造液态金属充型流动过程中气泡的形核规律
隋艳,李邦盛?,刘爱辉,熊艳,郭景杰,恒志
材料研究学报 , 2008,
Abstract: ?对离心力场作用下液态金属充型流动过程中气体的溶解度、气泡的形核条件、形核功、临界形核半径以及形核率进行了定量研究.结果表明,在离心力场作用下气体的溶解度是一个梯度量,随着离心半径和离心角速度的增大而增大;气泡的形核功和临界形核半径也随着离心半径和离心角速度的增大而增大,而气泡的形核率相应地减小;离心半径和离心角速度越大,对气体溶解度和气泡形核的影响越明显;因此,在离心力场作用下可通过提高离心旋转角速度和离心半径减少气孔缺陷.
黑豆餾油的制取及其制剂的調配法

中国中药杂志 , 1959,
Abstract: <正>黑豆餾油是由黑豆中干餾出来的一种黑色粘稠液体,陕晋民间用来治疗婴兒“胎毒”或“湿毒”?静菥V目称此药可治風疽瘡疥。我院皮膚科自1955年以来,为發揚祖国医学遺产,曾以此药治疗各型嬰兒湿疹,获得了良好的临床效果。其优点較一般常用的干餾油疗效高而副作用小,原料来源較易,成本低廉,可大量制作,易于推广。目前我院皮膚科除应用于婴兒湿疹外,并广泛用于成人各型湿疹、神經性皮炎、干癬等急慢性皮膚炎症,証实它具有消炎、收歛、抗菌等作用。我院正在研究其医疗机制。
银行会计与企业会计基本核算方法之差异

财会月刊 , 2011,
Abstract:   银行会计虽是从企业会计借鉴过来的,但它毕竟不同于企业会计。本文从会计科目、记账方法、会计凭证的设置和使用以及错账更正方法等方面比较了银行会计与企业会计的不同核算方法。  【关键词】银行会计企业会计会计科目错账更正方法记账方法会计凭证  银行会计是会计学科的一个重要分支,是将会计的基本原理和基本方法应用于银行的一门专业会计。它以货币为主要计量单位,采用独特的专门方法,对银行的经营活动进行连续、系统、全面的核算和监督,为银行经营管理者及各有关方提供相关的会计信息。既然银行会计是会计学的一个分支,那么,它必然和企业会计的基本核算方法有一定的相似之处。但是,银行毕竟不同于企业,银行是金融企业,主要是吸储放贷;而通常企业均以生产、制造为主,其职能是根本不同的。所以银行会计和企业会计的基本核算方法有一定的不同。本文拟从会计科目、记账方法、会计凭证的设置和使用以及错账更正方法等方面对银行会计与企业会计进行比较。
不同遗传背景儿童在不同调节状态下眼前节结构的变化
Changes in the anterior segment of eyes of children with different genetic background under different accommodations

戴怡康,,陆玮瑜,
DAI Yi-kang
, FU Wei-cai, LU Wei-yu, et al

- , 2016, DOI: 10.3969/j.issn.1674-8115.2016.01.016
Abstract: 目的 研究和分析不同遗传背景下,相同屈光状态儿童在不同的调节刺激下眼前节结构的变化。方法 采集正视眼儿童(+0.50~-0.50 DS)60例(60眼),分成2组:A组30例,儿童父母均为正视;B组30例,父母均为高度近视(≥6.0 DS)。所有受试儿童行散瞳主觉验光,调节放松和不同程度调节刺激下测量前房深度、晶状体厚度及暗瞳直径,比较两组间的差异。结果 两组儿童的年龄、调节幅度和裸眼视力差异均无统计学意义(P>0.05)。调节放松和诱发3D调节时两组间各测量指标的差异无统计学意义(P>0.05)。诱发6D调节时,A组前房深度变浅值和晶状体变厚值均大于B组(P<0.05),但暗瞳直径缩小值两组之间的差异无统计学意义(P>0.05)。结论 在6D调节刺激下,父母均为高度近视的儿童眼前节结构中前房深度以及晶状体厚度变化值均小于父母均为正视的儿童,这种差异是否造成今后屈光转归的不同尚需进一步研究。
: Objective To investigate and analyze the changes in the anterior segment of eyes of children with different genetic background and same refraction under different accommodations. Methods A total of 60 emmetropic children (60 eyes, +0.50~-0.50 DS) were enrolled and divided into A group (n=30) and B group (n=30). Parents of children of A group were emmetropic and parents of children of B group were highly myopic (≥6.0 DS). All children underwent subjective refraction after mydriasis. The anterior chamber depth, crystalline lens thickness, and dark pupil diameter were measured under relaxation and different accommodations. The difference between two groups was compared. Results The differences of age, accommodation amplitude, and naked vision between two groups were not statistically significant (P>0.05). The differences of measurements under relaxation and accommodation of 3D between two groups were not statistically significant (P>0.05). The decrease of anterior chamber depth and the increase of crystalline lens thickness of A group under accommodation of 6D were larger than those of B group (P<0.05), while the difference of the decrease of dark pupil diameter between two groups was not statistically significant (P>0.05). Conclusion Changes of anterior chamber depth and crystalline lens thickness in the anterior segment of eyes of children with highly myopic parents under accommodation of 6D are smaller than those of children with emmetropic parents. Whether this difference leads to the difference of refraction in the future still needs further study
“十三五”强化科技对文化支撑作用的渠道与路径
,蔡武进
- , 2015,
Abstract: 文化与科技历来如影随形。特别是在当今时代,新科技的迅猛发展更是极大地丰富了文化的表现形式和发展样态,拓展了文化的传播和传承方式,为文化的改革、创新、发展带来了无限可能。“十三五”期间,必须从国家宏观战略的高度,重视科技对于文化改革发展的支撑作用,要从文化领域关键技术的研发、文化领域技术标准的制订完善、文化科技平台及文化资源库的建设等方面,配合国家科技创新和文化创新两大战略规划,形成“十三五”国家文化科技发展规划和行动方案
无线传感器网络中拥塞和能量自适应路由协议研究
Research on Adaptive Congestion and Energy Routing Protocol in Wireless Sensor Networks
 [PDF]

蒋道霞, , 潘守
Hans Journal of Wireless Communications (HJWC) , 2014, DOI: 10.12677/HJWC.2014.41005
Abstract: 本文从无线传感器网络基于路由协议的拥塞控制技术入手,改进AODV路由协议,提出了拥塞和能量自适应的无线传感器网络路由协议WSNCA-AODV。通过节点缓存利用率、拥塞因子确定节点拥塞状态;通过节点拥塞状态、剩余能量、离Sink节点的距离来确定节点的转发满意度;以节点转发满意度为依据,创建主路由和辅助路由,在拥塞产生时,将数据流按比例分流在主路由和辅助路由上,实现WSN的拥塞自适应和能量自适应功能
 This article starts from the wireless sensor network routing protocol based on congestion control techniques, improves AODV routing protocol and proposes adaptive congestion and energy routing protocol for wireless sensor networks WSNCA-AODV. By node cache utilization, node congestion state can be determined by congestion factor. Through node congestion state, the remaining energy and distance from Sink node, node satisfaction forwarding can be determined. According to node satisfaction forwarding, the main routes and auxiliary routes can be created. When the WSN is congesting, it can proportionally split the data stream on the main routes and auxiliary routes, and achieve adaptive congestion and energy function in WSN.
Gas bubble nucleation in centrifugal casting liquid metal filling and flow process
离心铸造液态金属充型流动过程中气泡的形核规律

SUI Yanwei,Li Bangsheng,Liu Aihui,Xiong Yancai,Guo Jingjie,FU Hengzhi,
隋艳
,李邦盛,刘爱辉,熊艳,郭景杰,恒志

材料研究学报 , 2008,
Abstract: By means of quantitative analysis method,gas solubility,gas bubble nucleation condition, nucleation work,critical nucleation radius,and nucleation rate in centrifugal casting liquid metal filling and flow process are studied.The results show that with increasing the centrifugal radius and angular velocity,gas solubility as a gradient vector in centrifugal field,gas bubble nucleation work,and critical nucleation radius increase,but gas bubble nucleation rate decreases.Meanwhile,the effect of the cen- trifugal radius and angular velocity on gas solubility and gas bubble nucleation is more significant with their increasing.Therefore,porosity can be reduced through increasing the centrifugal radius and angular velocity in centrifugal field.
河流水质模型参数的“计算机扫描计算-图解-梯度搜索法”最优估值研究

环境科学学报 , 1985,
Abstract: 本文介绍了用“计算机扫描计算-图解-梯度搜索法”寻求河流水质数学模型最优参数的研究成果.该法能解决目前存在的用梯度法搜索参数时误差很大的问题.
银环蛇生态的初步研究

动物学杂志 , 1974,
Abstract:
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