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Expert consensus on standardized diagnosis and treatment for heat stroke(draft) 被引量:12
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作者 People’s Liberation Army Professional Committee of Critical Care Medicine 《Journal of Medical Colleges of PLA(China)》 CAS 2015年第1期1-10,共10页
Overview Heats stroke(HS)is severe sunstroke caused by a rapid increase in one’s core temperature in excess of 40°C from exposure to a hot and humid environment.HS is accompanied by serious clinical syndromes th... Overview Heats stroke(HS)is severe sunstroke caused by a rapid increase in one’s core temperature in excess of 40°C from exposure to a hot and humid environment.HS is accompanied by serious clinical syndromes that damage multiple organ systems.h ese syndromes include burning skin and impaired awareness,such as delir ium,conv ul sions,and loss of consciousness.Exertional heat stroke(EHS)is caused by a rapid increase in one’s core temperature in excess of 40°C from high intensity 展开更多
关键词 standardized CONSCIOUSNESS awareness CONSENSUS impaired DRAFT INFUSION INTRAVENOUS ACCOMPANIED nutrition
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Assessing Empathy in Anesthesia Residents with the Chinese Version of the Consultation and Relational Empathy: A Pilot Standardized Patient Program 被引量:2
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作者 Yahong Gong Lijian Pei +6 位作者 Xia Ruan Xu Li Xuerong Yu Ruiying Wang Weijia Wang Gang Tan Yuguang Huang 《Chinese Medical Sciences Journal》 CAS CSCD 2021年第2期79-84,共6页
Objectives To validate the reliability of the Chinese version of the Consultation and Relational Empathy(CARE)in physician-standardized patient(SP)encounter.We also tried to examine the agreement between video-based r... Objectives To validate the reliability of the Chinese version of the Consultation and Relational Empathy(CARE)in physician-standardized patient(SP)encounter.We also tried to examine the agreement between video-based ratings and in-room ratings,as well as the agreement between the faculty ratings and SP ratings.Methods The CARE was translated into Chinese.Forty-eight anesthesia residents were recruited to make preoperative interview in SP-counter.Performance of each resident was graded by in-room raters,video raters and SP raters.Consistency between different raters was examined.Results The Chinese-CARE measure demonstrated high scale reliability with a Cronbach's alpha value of 0.95 and high consistency in the in-room ratings in intraclass correlation(coefficient=0.888,P<0.001).Despite a good consistency in intraclass correlation,video ratings were significantly higher than in-room ratings(39.6±7.1 vs.24.0±10.0,P<0.001),and Wilcoxon signed-rank test indicated that the pass/fail rate was significantly higher based on video ratings than based on in-room ratings(45/48 vs.22/48,P<0.001).SP ratings had a moderate consistency with in-room faculty ratings(coefficient=0..568,P<0.001),and there was no significant difference between the pass/fail rates based on the in-room ratings and SP ratings(22/48vs.28/48,P=0.12).Conclusions The Chinese-CARE measure is reliable in the assessment of empathy during preoperative anesthesia interview.In-room and video ratings are not equivalent,while SP may provide a feasible alternative for the faculty rater in the assessment of communication skills with an appropriate measure. 展开更多
关键词 EMPATHY standardized patient encounter assessment rating modality
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Standardized processes of biomass briquetting densification fuel
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作者 ZHAO Fang ZHANG Ya-zhuo XU Zheng-dong LI Li ZHANG Shuang-bao 《Forestry Studies in China》 CAS 2012年第1期80-84,共5页
Forest biomass resources are available in enormous quantities in China. The development of forest biomass briquetting densification fuel, which has a high calorific value, can ease the energy shortage in China. But th... Forest biomass resources are available in enormous quantities in China. The development of forest biomass briquetting densification fuel, which has a high calorific value, can ease the energy shortage in China. But the molding technology is still at the primary stage with many questions unresolved, such as unequal distribution of resources, imperfect technology and an inadequate mechanism of market supply and demand. There are no consistent production and quality standards to refer to, which seriously hinder the industrialization of biomass molding technology. Hence, it is imperative to speed up the formulation of production standards of biomass briquetting densification fuel which not only conform to international standards, but are in accordance with national condi- tions in China. Drawing on the standards of biomass briquetting densification fuel in Europe, a standard system should be concerned with raw material collection, transport and storage of the end products, terminology, denomination and classification of molding equipment, as well as with technical conditions, testing methods, safety and environmental protection. The establishment of a stan- dard system is useful for the development of a healthy, orderly and sustainable biomass fuel industry. 展开更多
关键词 BIOMASS briquetting densification fuel standardized process
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Promoting standardized management of loaner instruments
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作者 WANG Xu TIAN Ying ZHOU Yiqin 《中西医结合护理(中英文)》 2018年第1期1-3,共3页
Objective The purpose of the present study is to provide scientific evidence for the implementation of standardized management of the loaner instruments by examining the process of receiving through issuing steps and ... Objective The purpose of the present study is to provide scientific evidence for the implementation of standardized management of the loaner instruments by examining the process of receiving through issuing steps and analyzing challenges encountered by the CSSD of our hospital. Methods The loaner instruments were collected and categorized into the control group( 2 639 pieces during the period of January 2013 to December 2014) and the observation group( 2 418 pieces during the period of January 2015 to December 2016). The possible causes of the challenges were carefully investigated and analyzed. Results After the implementation of standardized management procedures,the efficiency and qualified care of the loaner instruments was significantly improved by measuring qualified rate. The difference in the qualified rate between control and observation groups was statistically significant( P < 0. 01). Conclusion The implementation of the standardized management procedures is important for central sterilization supply departments in guarantee of safe supplies of the loaner instruments,reducing operation risks,and ultimately ensuring patient safety. 展开更多
关键词 loaner instruments standardized management procedures DISINFECTION
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基于湍流模型的飞行器温度场数值仿真研究
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作者 范福强 邢素霞 张俊举 《激光与红外》 CAS CSCD 北大核心 2024年第5期766-773,共8页
飞行器红外成像仿真需要不同飞行条件下的温度场分布。本文利用标准(Standard)k-ε模型、剪切应力传输(SST)k-ε模型和Spalart-Allmaras(S-A)模型分别进行数值模拟仿真计算,研究不同飞行速度和飞行高度下的飞行器温度场分布,并对不同模... 飞行器红外成像仿真需要不同飞行条件下的温度场分布。本文利用标准(Standard)k-ε模型、剪切应力传输(SST)k-ε模型和Spalart-Allmaras(S-A)模型分别进行数值模拟仿真计算,研究不同飞行速度和飞行高度下的飞行器温度场分布,并对不同模型的结果进行对比分析。首先,利用MultiGen Creator软件对飞行器进行三维建模;其次采用Hypemesh软件和Fluent meshing软件中进行面网格划分和体网格划分,最后采用Fluent 2022R1软件仿真飞行器静态温度场分布,通过改变湍流模型与边界条件设置,对不同飞行速度和不同高度下飞行器温度场进行数值模拟仿真,并与理论结果进行了对比分析。实验结果显示,3种湍流模型均能较好的模拟飞行器蒙皮与尾喷管内壁壁面温度值。飞行器蒙皮温度随着飞行马赫数的增加不断升高;随着飞行高度的升高而不断地降低,与理论结果变化规律一致。在尾喷管内壁面温度仿真中,3种湍流模型仿真的内壁面温度最高相差21 K,相对误差在1.8%左右,在红外仿真中近似忽略不计,故3种湍流模型均适合尾喷管内壁面温度场仿真。在蒙皮温度场仿真中,3种湍流模型仿真计算的蒙皮平均温度值与理论温度值的相对误差均在5%以内,均可满足红外成像仿真的温度差值要求,其中k-ε模型在蒙皮温度场模拟中与理论温度值最为接近,因此k-ε模型精度更高,更适合于飞行器的流场仿真,能更好地仿真出空气动力加热对飞行器温度场的影响。 展开更多
关键词 Standard k-ε模型 SST k-ε模型 S-A模型 飞行器 温度场模拟
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Research on batch multielement rapid quantitative analysis based on the standard curve-assisted calibration-free laserinduced breakdown spectroscopy method
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作者 Weiwei HAN Duixiong SUN +7 位作者 Guoding ZHANG Honglin WANG Kai GUO Yuzhuo ZHANG Haoliang WANG Denghong ZHANG Chenzhong DONG Maogen SU 《Plasma Science and Technology》 SCIE EI CAS CSCD 2024年第9期156-164,共9页
This study proposes a batch rapid quantitative analysis method for multiple elements by combining the advantages of standard curve(SC)and calibration-free laser-induced breakdown spectroscopy(CF-LIBS)technology to ach... This study proposes a batch rapid quantitative analysis method for multiple elements by combining the advantages of standard curve(SC)and calibration-free laser-induced breakdown spectroscopy(CF-LIBS)technology to achieve synchronous,rapid,and accurate measurement of elements in a large number of samples,namely,SC-assisted CF-LIBS.Al alloy standard samples,divided into calibration and test samples,were applied to validate the proposed method.SC was built based on the characteristic line of Pb and Cr in the calibration sample,and the contents of Pb and Cr in the test sample were calculated with relative errors of 6%and 4%,respectively.SC built using Cr with multiple characteristic lines yielded better calculation results.The relative contents of ten elements in the test sample were calculated using CF-LIBS.Subsequently,the SC-assisted CF-LIBS was executed,with the majority of the calculation relative errors falling within the range of 2%-5%.Finally,the Al and Na contents of the Al alloy were predicted.The results demonstrate that it effectively enables the rapid and accurate quantitative analysis of multiple elements after a single-element SC analysis of the tested samples.Furthermore,this quantitative analysis method was successfully applied to soil and Astragalus samples,realizing an accurate calculation of the contents of multiple elements.Thus,it is important to advance the LIBS quantitative analysis and its related applications. 展开更多
关键词 laser-induced breakdown spectroscopy standard curve quantitative analysis multielement
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Characteristics of laser-induced breakdown spectroscopy of liquid slag
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作者 董长言 于洪霞 +4 位作者 孙兰香 李洋 刘修业 周平 黄少文 《Plasma Science and Technology》 SCIE EI CAS CSCD 2024年第2期86-93,共8页
Rapid online analysis of liquid slag is essential for optimizing the quality and energy efficiency of steel production. To investigate the key factors that affect the online measurement of refined slag using laser-ind... Rapid online analysis of liquid slag is essential for optimizing the quality and energy efficiency of steel production. To investigate the key factors that affect the online measurement of refined slag using laser-induced breakdown spectroscopy(LIBS), this study examined the effects of slag composition and temperature on the intensity and stability of the LIBS spectra. The experimental temperature was controlled at three levels: 1350℃, 1400℃, and 1450℃. The results showed that slag composition and temperature significantly affected the intensity and stability of the LIBS spectra. Increasing the Fe content and temperature in the slag reduces its viscosity, resulting in an enhanced intensity and stability of the LIBS spectra. Additionally, 42 refined slag samples were quantitatively analyzed for Fe, Si, Ca, Mg, Al, and Mn at 1350℃, 1400℃, and 1450℃.The normalized full spectrum combined with partial least squares(PLS) quantification modeling was used, using the Ca Ⅱ 317.91 nm spectral line as an internal standard. The results show that using the internal standard normalization method can significantly reduce the influence of spectral fluctuations. Meanwhile, a temperature of 1450℃ has been found to yield superior results compared to both 1350℃ and 1400℃, and it is advantageous to conduct a quantitative analysis of the slag when it is in a “water-like” state with low viscosity. 展开更多
关键词 laser-induced breakdown spectroscopy(LIBS) SLAG temperature COMPOSITION VISCOSITY internal standard normalization partial least squares(PLS)
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Improved Berry-Esseen Bound for Rademacher Sum
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作者 MA li YE Liu HAN Xin-Fang 《应用概率统计》 CSCD 北大核心 2024年第6期910-941,共32页
Let X=Σ_(i=1)^(n)a_(i)ξ_(i)be a Rademacher sum with Var(X)=1 and Z be a standard normal random variable.This paper concerns the upper bound of|P(X≤x)−P(Z≤x)|for any x∈R.Using the symmetric properties and R softwa... Let X=Σ_(i=1)^(n)a_(i)ξ_(i)be a Rademacher sum with Var(X)=1 and Z be a standard normal random variable.This paper concerns the upper bound of|P(X≤x)−P(Z≤x)|for any x∈R.Using the symmetric properties and R software,this paper gets the following improved Berry-Esseen type bound under some conditions,|P(X≤x)−P(Z≤x)|≤P(Z∈(0,a1)),∀x∈R,which is one of the modified conjecture proposed by Nathan K.and Ohad K. 展开更多
关键词 sum of i.i.d.random variables standard normal distribution QUANTILE Berry-Esseen upper bound
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耳鼻咽喉专业住院医师规范化培训的思考 被引量:7
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作者 王明婕 于振坤 《中国耳鼻咽喉头颈外科》 CSCD 2013年第5期277-279,共3页
耳鼻咽喉专业住院医师规范化培训重点是培养临床实践能力,掌握正确的临床工作方法是培养正确临床思维的关键阶段,是理论与实践融会贯通的重要途径,对于培养合格的、适应新时代发展的医务工作者有重要意义。对耳鼻咽喉科临床实践教学应... 耳鼻咽喉专业住院医师规范化培训重点是培养临床实践能力,掌握正确的临床工作方法是培养正确临床思维的关键阶段,是理论与实践融会贯通的重要途径,对于培养合格的、适应新时代发展的医务工作者有重要意义。对耳鼻咽喉科临床实践教学应提高思想认识,强化教学意识,加强教学管理。在教学过程中,不仅要培养住院医师正确的临床思维、规范的临床技能,还要培养其具备良好的社会医德、医风,树立救死扶伤、全心全意为人民服务的思想,具有独立从事耳鼻咽喉科临床工作的能力。 展开更多
关键词 耳鼻咽喉科学(Otolaryngology) 教学(Teaching) 住院医师规范化培训(standardized residentstraining)
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二次雷达与飞行器之间信息交换方法与应用
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作者 咸儆醒 《长江信息通信》 2024年第2期25-29,共5页
文章介绍了二次雷达与飞行器之间进行信息交换的方法及其应用。首先将二次雷达从基本型A/C模式升级到S模式,再利用S模式的信息交换功能,实现地面发起的信息交换和空中发起的信息交换功能。我们通过对信息交换流程的设计,实现了飞机识别... 文章介绍了二次雷达与飞行器之间进行信息交换的方法及其应用。首先将二次雷达从基本型A/C模式升级到S模式,再利用S模式的信息交换功能,实现地面发起的信息交换和空中发起的信息交换功能。我们通过对信息交换流程的设计,实现了飞机识别符的获取与确认;通过信息交换实现了相邻地面雷达站之间的S模式协同监视。采用协同监视,降低询问频次,减少二次雷达的异步应答干扰,提高S模式目标监视的可靠性和连续性。 展开更多
关键词 二次雷达 A/C模式 S模式 Message Comm-A(MA) Message Comm-B(MB) Message Comm-C(MC) Message Comm-D(MD) Standard Length Message(SLM) Extended Length Message(ELM)
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气相色谱法测定多烯磷脂酰胆碱注射液中的苯甲醇 被引量:8
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作者 张骊 赵玉 杨更亮 《色谱》 CAS CSCD 北大核心 2007年第3期447-448,共2页
建立了多烯磷脂酰胆碱注射液中苯甲醇含量的测定方法。采用毛细管气相色谱法,以环己醇作为内标物,使用AT.SE-54毛细管色谱柱,程序升温,N2为载气,不分流进样模式,氢火焰离子化检测器(FID)检测。结果表明苯甲醇在0.01~20.0g/... 建立了多烯磷脂酰胆碱注射液中苯甲醇含量的测定方法。采用毛细管气相色谱法,以环己醇作为内标物,使用AT.SE-54毛细管色谱柱,程序升温,N2为载气,不分流进样模式,氢火焰离子化检测器(FID)检测。结果表明苯甲醇在0.01~20.0g/L范围内峰面积与内标峰面积的比值与其质量浓度呈良好的线性关系(r=0.9997),平均加样回收率为99.7%,相对标准偏差(RSD)为1.07%。该方法简便,准确,重现性好,精密度高,适用于多烯磷脂酰胆碱注射液中苯甲醇含量的测定,为同类药物的质量控制提供了实验依据。 展开更多
关键词 毛细管气相色谱法(capillary gas chromatography) 苯甲醇(benzyl alcohol) 多烯磷脂酰胆碱注射液 (Polyene Phosphatidyl CHOLINE Injection) 内标(internal standard)
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Standard映射及其三维扩展在多媒体加密中的应用 被引量:5
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作者 廉士国 王执铨 《东南大学学报(自然科学版)》 EI CAS CSCD 北大核心 2003年第z1期90-94,共5页
混沌映射因为初值敏感性、参数敏感性、遍历性和类随机性的特点 ,很适合用于信息加密 .离散化后的混沌映射与扩散机构相结合 ,与传统的密码算法相比 ,加解密速度更快 ,能够满足实时性要求 .与Baker和Cat映射相比 ,Standard映射具有更大... 混沌映射因为初值敏感性、参数敏感性、遍历性和类随机性的特点 ,很适合用于信息加密 .离散化后的混沌映射与扩散机构相结合 ,与传统的密码算法相比 ,加解密速度更快 ,能够满足实时性要求 .与Baker和Cat映射相比 ,Standard映射具有更大的密钥空间 ,更适合于信息加密 .因此将其扩展到三维空间 ,构造了基于离散Standard映射的多媒体加密方案 ,分析了Standard映射的参数敏感性 ,给出了置乱循环次数和扩散函数的选择方法 .实验结果表明 ,算法具有较高的安全性和较快的加解密速度 ,适合于多媒体数据 ,如图像、视频。 展开更多
关键词 混沌加密 Standard映射 多媒体加密 密码
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NOVEL GENERALIZED GREY INCIDENCE MODEL BASED ON INTERVAL GREY NUMBERS 被引量:4
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作者 谢乃明 郑静 辛江慧 《Transactions of Nanjing University of Aeronautics and Astronautics》 EI 2012年第2期118-124,共7页
To extend the traditional generalized grey incidence model, a novel grey incidence model based on inter- val grey numbers is constructed. Considering the numerical information of indexes cannot be accurately obtained ... To extend the traditional generalized grey incidence model, a novel grey incidence model based on inter- val grey numbers is constructed. Considering the numerical information of indexes cannot be accurately obtained and can be defined as interval grey numbers, the interval grey numbers are defined as standard interval grey num- bers which are split in white part and grey part. The absolute degree of incidence and relative degree of incidence based on the interval grey numbers are constructed and their arithmetic are given. Finally, an example about commercial aircraft index selection illuminates the effectiveness of the model. The results show that the model can sort indexes better and can extend the grey incidence models significantly. 展开更多
关键词 grey system grey incidence analysis standard interval grey number absolute degree of incidencerelative degree of incidence
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基于AES的S盒图像置乱算法研究 被引量:3
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作者 肖华勇 李建辉 边笛 《西北工业大学学报》 EI CAS CSCD 北大核心 2008年第1期74-78,共5页
提出了一种基于密码学最新加密算法AES中的S盒对图像进行置乱的技术。该技术包括灰度置乱、行列置乱、块置乱及3种置乱技术的综合运用。文中对置乱的效果提出了灰度直方图、平均差异度、置乱图与原图的相关系数评价方法,并采用该方法对... 提出了一种基于密码学最新加密算法AES中的S盒对图像进行置乱的技术。该技术包括灰度置乱、行列置乱、块置乱及3种置乱技术的综合运用。文中对置乱的效果提出了灰度直方图、平均差异度、置乱图与原图的相关系数评价方法,并采用该方法对各种置乱技术进行了实验分析。从实验结果来看,达到了很好的效果。文中还对该置乱算法复杂性、置乱的安全性、周期性等进行了分析。结果表明该技术对图像置乱简单高效,安全性高。 展开更多
关键词 AES(Advanced ENCRYPTION Standard)的S盒 相关系数 图像置乱 周期性 安全性
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解读1995版和2006版ASHRAE Standard 100——既有建筑节能标准 被引量:3
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作者 马素贞 龙惟定 《暖通空调》 北大核心 2008年第11期69-76,88,共9页
从新旧标准的框架、细节及内容等方面的变化来解读该标准,目的是探究美国目前节能技术的发展方向,对我国既有建筑节能改造提供一定的借鉴。
关键词 ASHRAE STANDARD 100 既有建筑 节能措施
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二元生物薄标样的制备技术方法 被引量:1
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作者 张德添 张学敏 +4 位作者 何昆 汪宝珍 杨怡 范宝昌 张飒 《福建分析测试》 CAS 1999年第2期1025-1028,共4页
本文着重介绍,在电镜X射线微区分析工作中,如何建立二元生物薄标样的制备技术方法,以及相关的计算公式等。
关键词 STANDARDS BSA X-RAY MICROANALYSIS
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Tree mortality and biomass loss in drought-aff ected forests of East Texas,USA 被引量:5
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作者 Mukti Ram Subedi Weimin Xi +2 位作者 Christopher B.Edgar Sandra Rideout-Hanzak Ming Yan 《Journal of Forestry Research》 SCIE CAS CSCD 2021年第1期67-80,共14页
Changes in tree mortality due to severe drought can alter forest structure,composition,dynamics,ecosystem services,carbon fl uxes,and energy interactions between the atmosphere and land surfaces.We utilized long-term(... Changes in tree mortality due to severe drought can alter forest structure,composition,dynamics,ecosystem services,carbon fl uxes,and energy interactions between the atmosphere and land surfaces.We utilized long-term(2000‒2017,3 full inventory cycles)Forest Inventory and Analysis(FIA)data to examine tree mortality and biomass loss in drought-aff ected forests for East Texas,USA.Plots that experienced six or more years of droughts during those censuses were selected based on 12-month moderate drought severity[Standardized Precipitation Evaporation Index(SPEI)-1.0].Plots that experienced other disturbances and inconsistent records were excluded from the analysis.In total,222 plots were retained from nearly 4000 plots.Generalized nonlinear mixed models(GNMMs)were used to examine the changes in tree mortality and recruitment rates for selected plots.The results showed that tree mortality rates and biomass loss to mortality increased overall,and across tree sizes,dominant genera,height classes,and ecoregions.An average mortality rate of 5.89%year−1 during the study period could be incited by water stress created by the regional prolonged and episodic drought events.The overall plot and species-group level recruitment rates decreased during the study period.Forest mortality showed mixed results regarding basal area and forest density using all plots together and when analyzed the plots by stand origin and ecoregion.Higher mortality rates of smaller trees were detected and were likely compounded by densitydependent factors.Comparative analysis of drought-induced tree mortality using hydro-meteorological data along with drought severity and length gradient is suggested to better understand the eff ects of drought on tree mortality and biomass loss around and beyond East Texas in the southeastern United States. 展开更多
关键词 Generalized nonlinear mixed model Endogenous factors Drought index standardized precipitation evaporation index(SPEI) Above-ground biomass Competition index Biomass lost to mortality East Texas
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海洋工程装备重防腐涂料的应用研究 被引量:15
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作者 张贤慧 方大庆 +2 位作者 钟承珠 徐初琪 苏雅丽 《南方能源建设》 2015年第3期23-27,42,共6页
介绍了海洋工程装备的腐蚀环境,阐述了海洋工程装备在海洋大气区、潮差浪溅区、海水浸没区、海泥区等不同部位的腐蚀特点及重防腐涂料的选用及性能评价标准,分析了目前国际上通用的海洋工程防腐设计标准结合实际案例,研发并构建了适应... 介绍了海洋工程装备的腐蚀环境,阐述了海洋工程装备在海洋大气区、潮差浪溅区、海水浸没区、海泥区等不同部位的腐蚀特点及重防腐涂料的选用及性能评价标准,分析了目前国际上通用的海洋工程防腐设计标准结合实际案例,研发并构建了适应苛刻海洋环境中的海洋工程钢结构防腐涂层体系。研究表明:构建的海洋工程钢结构防腐涂层体系性能卓越,满足NORSOK Standard M-501标准认证,可保障海洋工程装备在湿、高盐、干湿交替、浸没等强腐蚀海洋环境下的安全稳定运行。 展开更多
关键词 海洋工程装备 重防腐 风电涂料 NORSOK STANDARD M-501
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Empirical evaluation of confidence and prediction intervals for spatial models of forest structure in Jalisco,Mexico 被引量:3
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作者 Robin M.Reich C.Aguirre-Bravo +1 位作者 Vanessa A.Bravo Martin Mendoza Briseo 《Journal of Forestry Research》 SCIE CAS CSCD 2011年第2期159-166,共8页
In recent years there has been an increasing interest in developing spatial statistical models for data sets that are seemingly spatially independent.This lack of spatial structure makes it difficult,if not impossible... In recent years there has been an increasing interest in developing spatial statistical models for data sets that are seemingly spatially independent.This lack of spatial structure makes it difficult,if not impossible to use optimal predictors such as ordinary kriging for modeling the spatial variability in the data.In many instances,the data still contain a wealth of information that could be used to gain flexibility and precision in estimation.In this paper we propose using a combination of regression analysis to describe the large-scale spatial variability in a set of survey data and a tree-based stratification design to enhance the estimation process of the small-scale spatial variability.With this approach,sample units(i.e.,pixel of a satellite image) are classified with respect to predictions of error attributes into homogeneous classes,and the classes are then used as strata in the stratified analysis.Independent variables used as a basis of stratification included terrain data and satellite imagery.A decision rule was used to identify a tree size that minimized the error in estimating the variance of the mean response and prediction uncertainties at new spatial locations.This approach was applied to a set of n=937 forested plots from a state-wide inventory conducted in 2006 in the Mexican State of Jalisco.The final models accounted for 62% to 82% of the variability observed in canopy closure(%),basal area(m2·ha-1),cubic volumes(m3·ha-1) and biomass(t·ha-1) on the sample plots.The spatial models provided unbiased estimates and when averaged over all sample units in the population,estimates of forest structure were very close to those obtained using classical estimates based on the sampling strategy used in the state-wide inventory.The spatial models also provided unbiased estimates of model variances leading to confidence and prediction coverage rates close to the 0.95 nominal rate. 展开更多
关键词 tree-based stratified design generalized least squares standardized mean squared error Landsat-7 ETM+
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生态纺织品标准与Oeko-Tex^(®) Standard 100对比 被引量:2
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作者 韩莹莹 赵海浪 刘宇 《针织工业》 北大核心 2022年第4期76-80,共5页
将GB/T 18885—2020《生态纺织品技术要求》与2021版Oeko-Tex^(®)Standard 100标准进行详细比较,主要针对pH值、甲醛含量、可萃取重金属及重金属总含量、杀虫剂、有害染料、邻苯二甲酸酯、有机锡化合物、氯化苯和氯化甲苯、含氯苯... 将GB/T 18885—2020《生态纺织品技术要求》与2021版Oeko-Tex^(®)Standard 100标准进行详细比较,主要针对pH值、甲醛含量、可萃取重金属及重金属总含量、杀虫剂、有害染料、邻苯二甲酸酯、有机锡化合物、氯化苯和氯化甲苯、含氯苯酚、多环芳烃、全氟及多氟化合物、化学残余(残余溶剂、残余表面活性剂、残余润湿剂及其他)、抗菌整理剂和阻燃整理剂、紫外线稳定剂、硅氧烷、亚硝胺和亚硝基物质、可挥发物释放量、色牢度、有机棉纤维和材料19个测试项目。为纺织行业相关人员提供标准对比解读,并为今后GB/T 18885的修订提供一定的参考。 展开更多
关键词 生态纺织品 Oeko-Tex^(®)Standard 100 标准对比
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