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Digital Disparities:How Artificial Intelligence Can Facilitate Anti-Black Racism in the U.S.Healthcare Sector
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作者 Anthony Victor Onwuegbuzia 《International Relations and Diplomacy》 2024年第1期40-50,共11页
This paper delves into the intricate interplay between artificial intelligence(AI)systems and the perpetuation of Anti-Black racism within the United States medical industry.Despite the promising potential of AI to en... This paper delves into the intricate interplay between artificial intelligence(AI)systems and the perpetuation of Anti-Black racism within the United States medical industry.Despite the promising potential of AI to enhance healthcare outcomes and reduce disparities,there is a growing concern that these technologies may inadvertently/advertently exacerbate existing racial inequalities.Focusing specifically on the experiences of Black patients,this research investigates how the following AI components:medical algorithms,machine learning,and natural learning processes are contributing to the unequal distribution of medical resources,diagnosis,and health care treatment of those classified as Black.Furthermore,this review employs a multidisciplinary approach,combining insights from computer science,medical ethics,and social justice theory to analyze the mechanisms through which AI systems may encode and reinforce racial biases.By dissecting the three primary components of AI,this paper aims to present a clear understanding of how these technologies work,how they intersect,and how they may inherently perpetuate harmful stereotypes resulting in negligent outcomes for Black patients.Furthermore,this paper explores the ethical implications of deploying AI in healthcare settings and calls for increased transparency,accountability,and diversity in the development and implementation of these technologies.Finally,it is important that I prefer the following paper with a clear and concise definition of what I refer to as Anti-Black racism throughout the text.Therefore,I assert the following:Anti-Black racism refers to prejudice,discrimination,or antagonism directed against individuals or communities of African descent based on their race.It involves the belief in the inherent superiority of one race over another and the systemic and institutional practices that perpetuate inequality and disadvantage for Black people.Furthermore,I proclaim that this form of racism can be manifested in various ways,such as unequal access to opportunities,resources,education,employment,and fair treatment within social,economic,and political systems.It is also pertinent to acknowledge that Anti-Black racism is deeply rooted in historical and societal structures throughout the U.S.borders and beyond,leading to systemic disadvantages and disparities that impact the well-being and life chances of Black individuals and communities.Addressing Anti-Black racism involves recognizing and challenging both individual attitudes and systemic structures that contribute to discrimination and inequality.Efforts to combat Anti-Black racism include promoting awareness,education,advocacy for policy changes,and fostering a culture of inclusivity and equality. 展开更多
关键词 bias in algorithms Racial disparities in U.s.healthcare Discriminatory healthcare practices Black patient outcomes Automated decision-making and racism Machine Learning Natural language processing
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A High Efficiency Hardware Implementation of S-Boxes Based on Composite Field for Advanced Encryption Standard
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作者 Yawen Wang Sini Bin +1 位作者 Shikai Zhu Xiaoting Hu 《Journal of Computer and Communications》 2024年第4期228-246,共19页
The SubBytes (S-box) transformation is the most crucial operation in the AES algorithm, significantly impacting the implementation performance of AES chips. To design a high-performance S-box, a segmented optimization... The SubBytes (S-box) transformation is the most crucial operation in the AES algorithm, significantly impacting the implementation performance of AES chips. To design a high-performance S-box, a segmented optimization implementation of the S-box is proposed based on the composite field inverse operation in this paper. This proposed S-box implementation is modeled using Verilog language and synthesized using Design Complier software under the premise of ensuring the correctness of the simulation result. The synthesis results show that, compared to several current S-box implementation schemes, the proposed implementation of the S-box significantly reduces the area overhead and critical path delay, then gets higher hardware efficiency. This provides strong support for realizing efficient and compact S-box ASIC designs. 展开更多
关键词 Advanced Encryption standard (AEs) s-BOX tower Field Hardware Implementation Application specific Integration Circuit (AsIC)
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Theoretical Investigation of Exchange Bias in Compensated Cases 被引量:1
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作者 XIONG Zhi-Jie WANG Huai-Yu DING Ze-Jun 《Communications in Theoretical Physics》 SCIE CAS CSCD 2008年第11期1241-1244,共4页
The exchange bias (EB) of the ferromagnetic (FM)/antiferromagnetic (AFM) bilayers in a compensated case is studied by use of the many-body Green's function method of quantum statistical theory. The so-called co... The exchange bias (EB) of the ferromagnetic (FM)/antiferromagnetic (AFM) bilayers in a compensated case is studied by use of the many-body Green's function method of quantum statistical theory. The so-called compensated case is that there is no net magnetization on the AFM side of the interface. Our conclusion is that the EB in this case is primarily from the asymmetry of the interracial exchange coupling strengths between the FM and the two sublattices of the AFM. The effects of the layer thickness, temperature and the interracial coupling strength oi2 the exchange bias HE are investigated. The dependence of HE on the FM layer thickness and temperature is qualitatively in agreement with experimental results. HE is nearly inversely proportional to FM thickness. When temperature varies, both HE and He decrease with temperature increasing. The anisotropy of the FM layer only slightly influence He, but does not influence HE. 展开更多
关键词 exchange bias COERCIVITY compensated case Heisenberg Hamiltonian the many-body Green's function method
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Biased Random Number Generator Based on Bell's Theorem
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作者 谭勇刚 胡要花 杨海峰 《Chinese Physics Letters》 SCIE CAS CSCD 2016年第3期5-8,共4页
We propose a biased random number generation protocol whose randomness is based on the violation of the Clauser Home inequality. Non-maximally entangled state is used to maximize the Bell violation. Due to the rotatio... We propose a biased random number generation protocol whose randomness is based on the violation of the Clauser Home inequality. Non-maximally entangled state is used to maximize the Bell violation. Due to the rotational asymmetry of the quantum state, the ratio of Os to ls varies with the measurement bases. The experimental partners can then use their measurement outcomes to generate the biased random bit string. The bias of their bit string can be adjusted by altering their choices of measurement bases. When this protocol is implemented in a device-independent way, we show that the bias of the bit string can still be ensured under the collective attack. 展开更多
关键词 BELL in TEsT IT In biased Random Number Generator Based on Bell’s Theorem of Is that on
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Comparison of Advanced Technology Microwave Sounder Biases Estimated Using Radio Occultation and Hurricane Florence(2018) Captured by NOAA-20 and S-NPP
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作者 Xiaoxu TIAN Xiaolei ZOU 《Advances in Atmospheric Sciences》 SCIE CAS CSCD 2020年第3期269-277,共9页
The second Advanced Technology Microwave Sounder(ATMS)was onboard the National Oceanic and Atmospheric Administration(NOAA)-20 satellite when launched on 18 November 2017.Using nearly six months of the earliest NOAA-2... The second Advanced Technology Microwave Sounder(ATMS)was onboard the National Oceanic and Atmospheric Administration(NOAA)-20 satellite when launched on 18 November 2017.Using nearly six months of the earliest NOAA-20 observations,the biases of the ATMS instrument were compared between NOAA-20 and the Suomi National Polar-Orbiting Partnership(S-NPP)satellite.The biases of ATMS channels 8 to 13 were estimated from the differences between antenna temperature observations and model simulations generated from Meteorological Operational(MetOp)-A and MetOp-B satellites’Global Positioning System(GPS)radio occultation(RO)temperature and water vapor profiles.It was found that the ATMS onboard the NOAA-20 satellite has generally larger cold biases in the brightness temperature measurements at channels 8 to 13 and small standard deviations.The observations from ATMS on both S-NPP and NOAA-20 are shown to demonstrate an ability to capture a less than 1-h temporal evolution of Hurricane Florence(2018)due to the fact that the S-NPP orbits closely follow those of NOAA-20. 展开更多
关键词 ATMs NOAA-20 s-NPP biases calibration Hurricane Florence
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Inverse Length Biased Maxwell Distribution:Statistical Inference with an Application
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作者 Amer Ibrahim Al-Omari Ayed R.A.Alanzi 《Computer Systems Science & Engineering》 SCIE EI 2021年第10期147-164,共18页
In this paper,we suggested and studied the inverse length biased Maxell distribution(ILBMD)as a new continuous distribution of one parameter.The ILBMD is obtained by considering the inverse transformation technique of... In this paper,we suggested and studied the inverse length biased Maxell distribution(ILBMD)as a new continuous distribution of one parameter.The ILBMD is obtained by considering the inverse transformation technique of the Maxwell length biased distribution.Statistical characteristics of the ILBMD such as the moments,moment generating function,mode,quantile function,the coefficient of variation,coefficient of skewness,Moors and Bowley measures of kurtosis and skewness,stochastic ordering,stress-strength reliability,and mean deviations are obtained.In addition,the Bonferroni and Lorenz curves,Gini index,the reliability function,the hazard rate function,the reverse hazard rate function,the odds function,and the distributions of order statistics for the ILBMD,are presented.The ILBMD parameter is estimated using the maximum likelihood method,the method of moments,the maximum product of spacing technique,the ordinary and weight least square procedures,and the Cramer-Von-Mises methods.The Fishers information,as well as the Rényi and q-entropies,are derived.To investigate the usefulness of the proposed lifetime distribution and to illustrate the purpose of the study,a real dataset of the relief times of 20 patients receiving an analgesic is used. 展开更多
关键词 Maxell distribution inverse length biased Maxwell distribution Fisher’s information methods of estimation goodness of fit tests
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People's Festival under the “Oriental Pearl” TV Tower——The Third China Shanghai International Arts Festival
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《China & The World Cultural Exchange》 2002年第1期12-14,共3页
关键词 TV tower People’s Festival under the The Third China shanghai International Arts Festival Oriental Pearl
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The Tower of Hanoi for Evaluating Dysexecutive Syndrome in Patients with Parkinson’s:Standardization Values
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作者 Marcos Serrano-Duenas Belén Calero Maite Serrano 《Advances in Parkinson's Disease》 2017年第3期75-85,共11页
Objective: The Tower of Hanoi measures executive functions using non-verbal content and requires perception of position in space. The main objective of this study is to standardize the use of the TOH as a measurement ... Objective: The Tower of Hanoi measures executive functions using non-verbal content and requires perception of position in space. The main objective of this study is to standardize the use of the TOH as a measurement tool in Parkinson’s disease. Patients and Methods: Of the Control Group subjects, 192 (59.6%) were women, 223 subjects (69.25%) were able to perform the TOH with 3 discs. In the Parkinson’s Group, there were 57 women (39.3%), and 66 subjects (45.5%) did not get past that level. Results: If we take the TOH (with 3 or 4 discs) as a tool for discriminating between those who have dysexecutive syndrome and those who do not, we find that the Parkinson’s Group presents dysexecutive syndrome significantly more frequently than the Control Group (p ≤ 0.0064). Conclusion: We can conclude that dysexecutive syndrome is frequent in Parkinson’s patients and it is more prevalent than in the general population. 展开更多
关键词 Parkinson’s Disease Dysexecutive syndrome tower of Hanoi
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A New Principle of Fault Identification of on the Same Tower Based on Traveling Wave Reactive Powers
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作者 Hao Wu Ruikai Ye +2 位作者 Xingxing Dong Kunjian Yu Zhengwei Chang 《Journal of Power and Energy Engineering》 2019年第7期50-70,共21页
In order to improve the reliability of fault identification of the double-circuit transmission lines on the same tower, a new algorithm for fast protection of double-circuit transmission lines on the same tower based ... In order to improve the reliability of fault identification of the double-circuit transmission lines on the same tower, a new algorithm for fast protection of double-circuit transmission lines on the same tower based on the reactive powers of traveling wave is proposed. With the implementation of S-transform, the initial traveling wave reactive powers are calculated and the change characteristics of reactive power under different fault conditions are studied. The protection criterion is constructed by analyzing the ratio of the reactive powers of the same end on double-circuit transmission lines and the ratio of the reactive powers at both ends on the same line. According to the ratio of reactive power on the same side of the line and both ends of the same line, it is possible to identify whether the faults of the double-circuit line of the same tower occurred in or out of the protection zone. A large number of simulation results show that the protection performance is sensitive and reliable, and quick to respond. The criterion is simple and is basically not affected by fault initial angles, fault types, and transitional resistances. 展开更多
关键词 Double-Circuit Transmission Line on the sAME tower TRAVELING Wave Reactive Power s-TRANsFORM Fault Identification
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S型规整填料的液泛特性及模型研究 被引量:2
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作者 李群生 周士红 +3 位作者 章慧芳 许莉 王浩 王宝华 《石油化工》 CAS CSCD 北大核心 2012年第10期1154-1158,共5页
用直径为0.5 m、填料高度为1 m的有机玻璃塔,在常温常压下以空气和水为介质,在不同的喷淋密度下测定S型规整填料的液泛性能,并将其液泛气速与CY型和SQ型规整填料进行了比较。实验结果表明,S型规整填料具有较大的液泛气速,S-800型填料液... 用直径为0.5 m、填料高度为1 m的有机玻璃塔,在常温常压下以空气和水为介质,在不同的喷淋密度下测定S型规整填料的液泛性能,并将其液泛气速与CY型和SQ型规整填料进行了比较。实验结果表明,S型规整填料具有较大的液泛气速,S-800型填料液泛气速较CY-800和SQ-800平均提高了20.77%和15.34%。由规整填料层内流体的水力学理论关系式可推导得到S型填料的液泛气速模型,该模型的计算值与实验值的最大相对偏差均为3.09%,平均相对偏差为2.29%,可用来预测S型规整填料的液泛特性。 展开更多
关键词 s型规整填料 填料塔 液泛气速 液泛模型
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S/P模式计算的冷却塔烟气抬升高度敏感性试验 被引量:4
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作者 杨洪斌 刘玉彻 +2 位作者 汪宏宇 邹旭东 张云海 《气象与环境学报》 2011年第5期38-41,共4页
德国VDI3784的S/P模式为三维流体动力学积分模式,其方程主要描述了无穷小体积元素的质量、动量、静态污染物质量浓度及能量的守恒。利用德国模式进行了冷却塔烟气排放不同参数、不同大气条件下烟气抬升高度的敏感性试验。结果表明:在影... 德国VDI3784的S/P模式为三维流体动力学积分模式,其方程主要描述了无穷小体积元素的质量、动量、静态污染物质量浓度及能量的守恒。利用德国模式进行了冷却塔烟气排放不同参数、不同大气条件下烟气抬升高度的敏感性试验。结果表明:在影响烟气抬升高度的3个气象要素(风速、气温和湿度)中,风速和气温的变化对结果影响较大,而湿度影响较小。在D类稳定度,当环境风速从0.1 m/s增加到15.0 m/s时,抬升高度从711.7 m变为38.5 m。随着环境温度的升高,抬升高度明显单调变小;当稳定度为A类,环境温度从10升到40时,烟气抬升最大高度从688.9 m降低到45.1 m,降低了14倍多。而环境湿度的变化,对抬升高度的影响不是很明显。对于E类稳定度和F类稳定度,当环境湿度从20%增加到70%,最大抬升高度分别从115.3 m和84.6 m降到112.9 m和81.7 m,分别降低了3.43%和2.08%。在影响烟气抬升高度的其他3个因素(凉水塔直径、烟气出口速度和混合气体温度)中,混合气体温度的变化对结果影响较大,而凉水塔直径和烟气出口速度的影响较小。在各类稳定度条件下,当出口温度从20变到90时,烟气抬升高度增加1.2—13.3倍;在各类稳定度条件下,当凉水塔直径从30 m变到90 m,烟气抬升高度仅增加0.63—1.40倍;在各类稳定度条件下,当出口速度从2.5 m/s变到8.0 m/s,烟气抬升高度增加了0.24—0.74倍。 展开更多
关键词 冷却塔 烟气抬升最大高度 s/P模式 敏感性试验
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Austal 2000应用于国内“烟塔合一”类项目大气影响评价 被引量:5
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作者 周阳 王红宇 +2 位作者 李志强 王伟 赫洁 《环境监测管理与技术》 2012年第1期56-61,共6页
简述了德国"烟塔合一"类大气污染扩散模式,以及相关模式Austal 2000的应用方法,修正了气象参数以适合本地化应用。以天津某电厂为实例,将Austal 2000模式"烟塔合一"和烟囱排烟方式的计算结果进行了对比分析。结果表... 简述了德国"烟塔合一"类大气污染扩散模式,以及相关模式Austal 2000的应用方法,修正了气象参数以适合本地化应用。以天津某电厂为实例,将Austal 2000模式"烟塔合一"和烟囱排烟方式的计算结果进行了对比分析。结果表明,在进行本地化修改后,Austal 2000模式适用于国内有关项目大气预测评价,但从环境影响角度考虑,"烟塔合一"相对于高烟囱排放方式没有明显优势,应用时需慎重。 展开更多
关键词 大气扩散 环境影响评价 烟塔合一 Austal 2000 s/P模式
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有限群的π-闭-sylow塔-s-补(Ⅰ) 被引量:1
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作者 於遒 翟余华 +1 位作者 李科生 张新建 《淮阴工学院学报》 CAS 2003年第5期1-3,共3页
称群G的子群H在G中π-闭-sylow塔-s-可补的,如果存在G的子群K,使得G=HK且K/K∩H_G为π-sy-low塔群,此时,K被称为H在群G中的π-闭-sylow塔-s-补。讨论了π-闭-sylow塔群的性质并应用这些性质给出了一个群π-sylow塔-s-补的一些结论。主... 称群G的子群H在G中π-闭-sylow塔-s-可补的,如果存在G的子群K,使得G=HK且K/K∩H_G为π-sy-low塔群,此时,K被称为H在群G中的π-闭-sylow塔-s-补。讨论了π-闭-sylow塔群的性质并应用这些性质给出了一个群π-sylow塔-s-补的一些结论。主要结论有:设G为群,H为群G的子群,则下列论断成立:(1)如果K是H在G中的π-闭-sylow塔-s-补,且NG,则KN/N为HN/N在G/N中的π-闭-sylow塔-s-补;(2)令NC且N<H,若K/N是H/N在G/N中的π-闭-sylow塔-s-补,则K为H在G中的π-闭-sylow塔-s-补;(3)如果H≤T≤G,并且K是H在G中的π-闭-sylow塔-s-补,那么K∩T为H在T中的π-闭-sylow塔-s-补。 展开更多
关键词 有限群 Π-闭-sYLOW塔群 π-闭-sylow塔-s-补 称群 子群
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基于C/S模式的标校远程监控系统的软件设计 被引量:3
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作者 周江 潘高峰 谢勇 《遥测遥控》 2010年第3期55-58,64,共5页
介绍一种标校塔标校设备远程监控系统,其监控软件利用现代控制和信息化技术进行环境工况、标校设备/设施、仪器、视频等信息采集,建立测量船测控设备终端与标校塔控制系统的信息互联,从而实现测量船对标校设备的实时监控。该系统解决了... 介绍一种标校塔标校设备远程监控系统,其监控软件利用现代控制和信息化技术进行环境工况、标校设备/设施、仪器、视频等信息采集,建立测量船测控设备终端与标校塔控制系统的信息互联,从而实现测量船对标校设备的实时监控。该系统解决了传统标校工作模式下资源调度困难、标校保障效率不高的问题,具有控制功能安全可靠、操作简捷、实时性强、扩展性好的优点。 展开更多
关键词 标校塔 远程监控 GPIB MODBUs C/s模式
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π-闭-Sylow塔群的一些必要条件 被引量:1
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作者 於遒 查明明 李保军 《淮阴工学院学报》 CAS 2005年第3期10-12,共3页
称群G为π-闭-Sylow塔群,若群G存在正规Hallπ-子群为Sylow塔群。在π-闭-Sylow塔群的性质的基础上,利用极大子群、s-正规子群等,给出了一个π-闭-Sylow塔群为π-超可解群、可解群的一些条件。主要结论:(1)若G为π-闭-Sylow塔群,且G的包... 称群G为π-闭-Sylow塔群,若群G存在正规Hallπ-子群为Sylow塔群。在π-闭-Sylow塔群的性质的基础上,利用极大子群、s-正规子群等,给出了一个π-闭-Sylow塔群为π-超可解群、可解群的一些条件。主要结论:(1)若G为π-闭-Sylow塔群,且G的包含Hallπ'-子群的极大子群在G中的指数为素数,则G为π-超可解群。(2)G为π-闭-Sylow塔群,若G中任一Hallπ'-子群的素数幂阶子群在G中s-正规,则G为可解群。 展开更多
关键词 Π-闭-sYLOW塔群 极大子群 s-正规子群 π-超可解群 可解群
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应用S/P模式评估自然通风冷却塔排放脱硫后烟气对大气环境的影响 被引量:7
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作者 曾德勇 《中国电力》 CSCD 北大核心 2006年第2期81-85,共5页
应用德国烟气通过冷却塔排放的扩散模式——VDI 3784标准的S/P模式和烟气抬升后空气污染物扩散的计算模型VDI 3782、环境气象学大气扩散模式(颗粒物)VDI 3945,对自然通风冷却塔排放脱硫后烟气对大气环境影响的评估方式、基本参数、冷却... 应用德国烟气通过冷却塔排放的扩散模式——VDI 3784标准的S/P模式和烟气抬升后空气污染物扩散的计算模型VDI 3782、环境气象学大气扩散模式(颗粒物)VDI 3945,对自然通风冷却塔排放脱硫后烟气对大气环境影响的评估方式、基本参数、冷却塔烟羽的抬升、气象数据和计算进行了简要分析。分析表明,弱风条件下冷却塔排放比烟囱排放要好;大风条件下情况相反,但总的情况适合污染物排放。并以某电厂为例,计算了抬升高度和扩散后的落地质量浓度,同时和烟囱扩散效果进行了对比,表明这个模式是可行的,污染物的落地质量浓度小于环境质量空气标准的1%,在大多数气象条件下,烟塔的排放要优于烟囱排放。 展开更多
关键词 脱硫后烟气 s/P模式 自然通风冷却塔 大气环境 污染物扩散 落地质量浓度
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再压缩S-CO_(2)塔式光热发电系统模拟及参数优化 被引量:2
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作者 王智 闫锐鸣 +2 位作者 刘亚丽 张玲 陶鸿俊 《汽轮机技术》 北大核心 2021年第6期422-426,共5页
建立了再压缩S-CO_(2)布雷顿循环模型,对S-CO_(2)再压缩布雷顿循环的塔式太阳能光热系统的镜场效率、吸热塔效率、冷源损失等指标进行模拟以及对分流比、压比、透平入口温度等参数进行研究,同时计算得出储热所需时长随全年各月的变化曲... 建立了再压缩S-CO_(2)布雷顿循环模型,对S-CO_(2)再压缩布雷顿循环的塔式太阳能光热系统的镜场效率、吸热塔效率、冷源损失等指标进行模拟以及对分流比、压比、透平入口温度等参数进行研究,同时计算得出储热所需时长随全年各月的变化曲线。通过时间序列,得出两分两至日镜场系统与储热系统的供能情况。模拟结果表明:镜场遮挡效率和余弦效率随塔高的增加而增大,大气衰减效率和截断效率随塔高增加而减小;储热时长随日均辐射总量和日照时长有明显的季节差异,春秋分以及夏至日储热系统可以保证系统在无光照情况下实现满发,但冬至日储热系统无法蓄满热,则要想使系统持续运行,则夜里发电功率仅为17.34MW。最后根据压比(2~3.6)、分流比、透平入口温度(500℃~800℃)对于系统循环效率的影响曲线,计算得出系统的参数优化值。 展开更多
关键词 s-CO_(2) 塔式太阳能光热系统 时间序列 储热 参数模拟
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混合Poisson分布随机递增的条件
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作者 邱国新 姜海波 黄绍文 《工程数学学报》 CSCD 北大核心 2009年第1期155-158,共4页
本文讨论服从混合Poisson分布的随机变量,证明了当混合参数依期望序,通常意义的随机序,增凸(凹)序,增的对数凸(凹)序,s-凸序或者下端有偏序增加时,变量本身也依相应的随机序增加。
关键词 期望序 增凸序 增的对数凸序 s-凸序 下端有偏序 混合Poisson分布
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风力发电机组装配式预应力混凝土塔筒疲劳承载力分析
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作者 张后禅 张祥 《混凝土与水泥制品》 2024年第10期64-67,共4页
在设计使用年限内,风力发电机组装配式预应力混凝土塔筒的疲劳问题非常突出,尤其在塔筒1/2高度以上区域。国内标准的疲劳验算公式是基于等幅疲劳2×10^(6)次的试验研究结果,而风力发电机组混凝土塔筒的疲劳次数在3×10^(8)以上... 在设计使用年限内,风力发电机组装配式预应力混凝土塔筒的疲劳问题非常突出,尤其在塔筒1/2高度以上区域。国内标准的疲劳验算公式是基于等幅疲劳2×10^(6)次的试验研究结果,而风力发电机组混凝土塔筒的疲劳次数在3×10^(8)以上,故国内标准不适用风电机组混凝土塔筒的疲劳验算。而欧标Fib Model Code for Concrete Structures 2010(FIB规范)采用基于S-N曲线的Palmgren-Miner累积损伤方法进行混凝土疲劳验算,可以解决高次数的疲劳问题。介绍了FIB规范中混凝土塔筒常用的Ⅲ级和Ⅳ级设计方法,通过具体案例分析了混凝土塔筒疲劳承载力的影响因素。结果表明:提高混凝土强度等级和加大塔筒壁厚,可以有效提高塔筒的疲劳承载力。可为风力发电机组装配式预应力混凝土塔筒实际设计提供参考。 展开更多
关键词 风力发电机组装配式预应力混凝土塔筒 疲劳 s-N曲线 混凝土强度等级 壁厚
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有限群的π-闭-Sylow塔群的性质
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作者 於遒 查明明 李保军 《淮海工学院学报(自然科学版)》 CAS 2005年第2期4-6,共3页
称群G为π闭Sylow塔群,若群G存在正规Hallπ子群为Sylow塔群.在π闭Sylow塔群性质的基础上,利用极大子群、s可补子群等,给出了一个π闭Sylow塔群为π超可解群、可解群的一些条件.主要结论:若G为π闭Sylow塔群,且G的包含Hallπ′子群的... 称群G为π闭Sylow塔群,若群G存在正规Hallπ子群为Sylow塔群.在π闭Sylow塔群性质的基础上,利用极大子群、s可补子群等,给出了一个π闭Sylow塔群为π超可解群、可解群的一些条件.主要结论:若G为π闭Sylow塔群,且G的包含Hallπ′子群的极大子群在G中的指数为素数,则G为π超可解群;G为π闭Sylow塔群,若G中任一Hallπ′子群的素数幂阶子群在G中s可补,则G为可解群. 展开更多
关键词 Π-闭-sYLOW塔群 极大子群 s-可补 π-超可解群 可解群
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