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Damage effectiveness assessment method for anti-ship missiles based on double hierarchy linguistic term sets and evidence theory 被引量:3
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作者 YAO Tianle WANG Weili +2 位作者 MIAO Run DONG Jun YAN Xuefei 《Journal of Systems Engineering and Electronics》 SCIE EI CSCD 2022年第2期393-405,共13页
The research on the damage effectiveness assessment of anti-ship missiles involves system science and weapon science, and has essential strategic research significance. With comprehensive analysis of the specific proc... The research on the damage effectiveness assessment of anti-ship missiles involves system science and weapon science, and has essential strategic research significance. With comprehensive analysis of the specific process of the damage assessment process of anti-missile against ships, a synthetic damage effectiveness assessment process is proposed based on the double hierarchy linguistic term set and the evidence theory. In order to improve the accuracy of the expert ’s assessment information, double hierarchy linguistic terms are used to describe the assessment opinions of experts. In order to avoid the loss of experts ’ original information caused by information fusion rules, the evidence theory is used to fuse the assessment information of various experts on each case. Good stability of the assessment process can be reflected through sensitivity analysis, and the fluctuation of a certain parameter does not have an excessive influence on the assessment results. The assessment process is accurate enough to be reflected through comparative analysis and it has a good advantage in damage effectiveness assessment. 展开更多
关键词 anti-ship missile damage effect assessment linguistic term set evidence reasoning
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Effect of parameter setting and spectral normalization approach on study of matrix effect by laser induced breakdown spectroscopy of Ag–Zn binary composites 被引量:1
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作者 Harse SATTAR Liying SUN +3 位作者 Muhammad IMRAN Ran HAI Ding WU Hongbin DING 《Plasma Science and Technology》 SCIE EI CAS CSCD 2019年第3期155-166,共12页
The complex nature of laser-material interaction causes non-stoichiometric ablation of alloy samples.This is attributed to matrix effect, which reduces analyzing capability. To address this issue, the analytical perfo... The complex nature of laser-material interaction causes non-stoichiometric ablation of alloy samples.This is attributed to matrix effect, which reduces analyzing capability. To address this issue, the analytical performance of three different normalization methods, namely normalization with background, internal normalization and three point smoothing techniques at different parameter settings is studied for quantification of Ag and Zn by Laser induced breakdown spectroscopy(LIBS).The LIBS spectra of five known concentration of silver zinc binary composites have been investigated at various laser irradiances(LIs). Calibration curves for both Ag(I) line(4d^(10)5s^2S_(1/2)→4d^(10)5p^2P_(1/2) at 338.28 nm) and Zn(I) line(4s5s^3S_1→4s4p^3P_2 at 481.053 nm) have been determined at LI of 5.86?×?10^(10)W cm^(-2). Slopes of these calibration curves provide the valuation of matrix effect in the Ag–Zn composites. With careful sample preparation and normalization after smoothing at optimum parameter setting(OPS), the minimization of sample matrix effect has been successfully achieved. A good linearity has been obtained in Ag and Zn calibration curve at OPS when normalized the whole area of spectrum after smoothing and the obtained coefficients of determination values were R^2?=?0.995 and 0.998 closer to 1. The results of matrix effect have been further verified by analysis of plasma parameters. Both plasma parameters showed no change with varying concentration at OPS. However, at high concentration of Ag, the observed significant changes in both plasma parameters at common parameter setting PS-1 and PS-2 were the gesture of matrix effect. In our case, the better analytical results were obtained at smoothing function with optimized parameter setting that indicates it is more efficient than normalization with background and internal normalization method. 展开更多
关键词 Ag–Zn COMPOSITES laser induced BREAKDOWN spectroscopy optimum parameter setting SELF-ABSORPTION matrix effect
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Research on the Field Setting and Teaching Mode and the Influences on the Effect of Volleyball Teaching in Colleges and Universities
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作者 Jian Wang 《International Journal of Technology Management》 2016年第12期4-6,共3页
This paper conducts the analysis on the fleld setting and teaching mode and the influences on the effect of volleyball teaching in colleges and universities. The volleyball class organization form must vivid, be livel... This paper conducts the analysis on the fleld setting and teaching mode and the influences on the effect of volleyball teaching in colleges and universities. The volleyball class organization form must vivid, be lively, be diverse and the core teaching method and the method also want novel changeable, cannot always the same old story. If the warming-up exercise each time all is jogs with the empty-handed exercises, the student can produce was sick of that cannot raise any interest, the effect cannot be good. In the sports teaching, and that provides the feedback information promptly in the establishment appropriate effective goal in the foundation, in addition the qualitative appraisal, namely the full use goal establishment and the feedback information. We promote the traditional teaching method by integrating the latest methodologies that will be meaningful. 展开更多
关键词 Field setting Teaching Mode Volleyball Teaching COLLEGES effect.
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SET悬吊训练结合生物反馈技术在卒中患者下肢运动功能训练中的疗效观察
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作者 李旭锋 邓桂芬 陈礼彬 《黑龙江医药》 CAS 2024年第5期1059-1062,共4页
目的:探讨SET悬吊训练结合生物反馈技术在卒中患者下肢运动功能训练中的疗效。方法:选取佛山市南海区第五人民医院2022年1月—2023年12月期间收治的卒中下肢运动功能障碍患者72例为研究对象,分为2组,对照组(36例,实施SET悬吊训练)和实验... 目的:探讨SET悬吊训练结合生物反馈技术在卒中患者下肢运动功能训练中的疗效。方法:选取佛山市南海区第五人民医院2022年1月—2023年12月期间收治的卒中下肢运动功能障碍患者72例为研究对象,分为2组,对照组(36例,实施SET悬吊训练)和实验组(36例,SET悬吊训练结合生物反馈技术),比较两组干预效果。结果:治疗后,实验组患者肌张力低于对照组;治疗后,实验组患者运动功能(FMA)评分、平衡功能(BBS)评分高于对照组(P<0.05)。结论:SET悬吊训练结合生物反馈技术对改善卒中患者下肢运动功能具有积极意义,有效改善患者的神经肌肉控制、降低肌张力、增强平衡和运动功能,进而提高其生活质量,值得推广和实施。 展开更多
关键词 set悬吊训练 生物反馈技术 卒中 下肢运动功能 疗效
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超深亚微米工艺下的电路级耦合SET脉冲注入 被引量:1
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作者 刘必慰 陈书明 +1 位作者 梁斌 刘征 《Journal of Semiconductors》 EI CAS CSCD 北大核心 2008年第9期1819-1822,共4页
超深亚微米工艺下在电路模拟器中使用独立电流源方法的单粒子瞬态(single event transient,SET)脉冲注入与实验结果有很大误差.作者提出了一种基于二维查找表的耦合电流源注入的方法,并且基于开源的SPICE代码实现.该方法的计算结果与器... 超深亚微米工艺下在电路模拟器中使用独立电流源方法的单粒子瞬态(single event transient,SET)脉冲注入与实验结果有很大误差.作者提出了一种基于二维查找表的耦合电流源注入的方法,并且基于开源的SPICE代码实现.该方法的计算结果与器件/电路混合模拟接近,而其计算时间远小于混合模拟.该法与SPICE集成,可以引入实验测量数据,适合于大规模组合电路的SET错误率分析. 展开更多
关键词 单粒子瞬态 脉冲注入 辐射效应
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Level Set方法在地面效应数值模拟中的应用 被引量:1
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作者 何琨 陈坚强 毛枚良 《应用力学学报》 CAS CSCD 北大核心 2013年第3期328-333,471,共6页
利用Level Set方法隐式捕捉界面并能处理复杂的物质界面及其拓扑结构变化(如合并、交叉、破碎等)情况的优势,基于可压缩N-S方程的预处理技术,采用基于界面两侧介质黎曼关系的修正虚拟流体方法对介质边界进行处理;将只能应用于可压缩流... 利用Level Set方法隐式捕捉界面并能处理复杂的物质界面及其拓扑结构变化(如合并、交叉、破碎等)情况的优势,基于可压缩N-S方程的预处理技术,采用基于界面两侧介质黎曼关系的修正虚拟流体方法对介质边界进行处理;将只能应用于可压缩流动界面模拟的修正虚拟流体方法推广应用于不可压缩流动问题的模拟,数值模拟了气-水运动界面与近水面飞行器的相互影响规律。通过与将水面视为对称面的简化模型对比发现:利用自由运动界面模型计算的NACA6409翼型升力较小,能更准确地反映飞行器流场对水面形状的影响,其结果更为符合实际;文中还对比了翼型距水面不同高度时的结果,得到了翼型受水面影响的强弱与翼型距水面的高度成反比的结论。 展开更多
关键词 地面效应 LEVEL set方法 修正虚拟流体方法 预处理方法
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Representations of Co-regular Subsets on Euclidean Spaces 被引量:2
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作者 邱玉文 王莉萍 赵希顺 《Chinese Quarterly Journal of Mathematics》 CSCD 北大核心 2007年第2期252-257,共6页
For the computability of co-regular subsets in metric spaces, the properties of the co-regular subsets and several reasonable representations on co-regular sets have been suggested in this paper. As last, the 'weaker... For the computability of co-regular subsets in metric spaces, the properties of the co-regular subsets and several reasonable representations on co-regular sets have been suggested in this paper. As last, the 'weaker or stronger' relations of these representations have been revealed. 展开更多
关键词 type-2 theory of effectivity COMPUTABILITY computable set REPRESENTATIONS
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基于Vague Sets-topsis理论的爆破方案优选 被引量:2
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作者 李小贝 蒙云琪 +1 位作者 吴剑锋 吝学飞 《爆破》 CSCD 北大核心 2018年第2期94-100,共7页
为了解决复杂框架结构楼房爆破拆除过程中如何选择爆破方案的技术难题,建立改进的Vague Sets-topsis综合评价指标模型,对爆破方案进行优选。首先对爆破方案中的关键参数建立评审指标集;然后利用逼近理想解的排序法,计算出各个方案的综... 为了解决复杂框架结构楼房爆破拆除过程中如何选择爆破方案的技术难题,建立改进的Vague Sets-topsis综合评价指标模型,对爆破方案进行优选。首先对爆破方案中的关键参数建立评审指标集;然后利用逼近理想解的排序法,计算出各个方案的综合优越度,从而确定各个爆破方案的优劣;最后以铁四院前大楼爆破为例,采用改进的Vague Sets-topsis理论模型对"内向折叠爆破"(S1)、"双向折叠爆破"(S2)和"单向折叠双切口爆破"(S3)等不同方案的关键参数进行综合对比分析,得到方案的最优排序为:S3>S2>S1。实际爆破拆除实例表明:S3拆除效果良好,证明采用改进的Vague Sets-topsis理论模型可以用于复杂框架结构楼房控制爆破拆除优选。 展开更多
关键词 爆破拆除 VAGUE sets-topsis理论 折叠爆破 爆破效果
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Topology and Shape Optimization of 2-D and 3-D Micro-ArchitecturedThermoelastic Metamaterials Using a Parametric Level Set Method 被引量:1
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作者 Ellie Vineyard Xin-Lin Gao 《Computer Modeling in Engineering & Sciences》 SCIE EI 2021年第6期819-854,共36页
2-D and 3-D micro-architectured multiphase thermoelastic metamaterials are designed and analyzed using a parametric level set method for topology optimization and the finite element method.An asymptotic homogenization... 2-D and 3-D micro-architectured multiphase thermoelastic metamaterials are designed and analyzed using a parametric level set method for topology optimization and the finite element method.An asymptotic homogenization approach is employed to obtain the effective thermoelastic properties of the multiphase metamaterials.Theε-constraint multi-objective optimization method is adopted in the formulation.The coefficient of thermal expansion(CTE)and Poisson’s ratio(PR)are chosen as two objective functions,with the CTE optimized and the PR treated as a constraint.The optimization problems are solved by using the method of moving asymptotes.Effective isotropic and anisotropic CTEs and stiffness constants are obtained for the topologically optimized metamaterials with prescribed values of PR under the constraints of specified effective bulk modulus,volume fractions and material symmetry.Two solid materials along with one additional void phase are involved in each of the 2-D and 3-D optimal design examples.The numerical results reveal that the newly proposed approach can integrate shape and topology optimizations and lead to optimal microstructures with distinct topological boundaries.The current method can topologically optimize metamaterials with a positive,negative or zero CTE and a positive,negative or zero Poisson’s ratio. 展开更多
关键词 Topology optimization thermoelastic metamaterial level set method sensitivity analysis Poisson’s ratio coefficient of thermal expansion effective elastic properties
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基于二节点模型的热舒适评价指标新标准有效温度(SET~*)存在问题的研究 被引量:1
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作者 杜衡 杨昌智 《暖通空调》 2018年第12期12-17,共6页
新标准有效温度SET*是Gagge等人于20世纪70年代提出的热舒适评价指标,收录于ASHRAE标准,长期以来得到了广泛的应用。但在实际应用过程中发现,现有SET*计算方法并不能使实际环境与标准环境达到良好的等价,而对热环境评价产生误差,在实际... 新标准有效温度SET*是Gagge等人于20世纪70年代提出的热舒适评价指标,收录于ASHRAE标准,长期以来得到了广泛的应用。但在实际应用过程中发现,现有SET*计算方法并不能使实际环境与标准环境达到良好的等价,而对热环境评价产生误差,在实际环境代谢率较高时误差更显著。分析了SET*理论与计算方法存在的问题以及误差产生的原因。指出现有SET*指标计算方法较适用于人体代谢率接近1met的热环境评价。若实际环境代谢率较高,计算方法需作修正。 展开更多
关键词 二节点模型 新标准有效温度 代谢率 平均皮肤温度 皮肤湿润度 皮肤散热量 热舒适
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Frequency Effects of Fine Thin Layer
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作者 Zhang Shuangxi(Department of Geophysics, China University of Geosciences, Wuhan 430074)Yuan Tao Zhang Wenxian(Northwest Petroleum Geology Bureau, Ministry of Geology and Mineral Resources, Xinjiang 830011)Xiong Weigang(Department of Geophysics, China Uni 《Journal of Earth Science》 SCIE CAS CSCD 1994年第1期92-96,共5页
One of the most important research task in reservoir engineering now is to resolve the fine thin layer. What are the characteristics of the fine thin layer? This paper gives the answer in frequency domain. The frequen... One of the most important research task in reservoir engineering now is to resolve the fine thin layer. What are the characteristics of the fine thin layer? This paper gives the answer in frequency domain. The frequency feature of fine thin layer set obtained is grating. The frequence effects of rhythmic thin layer, on the other hand, is different from those of graded thin layer; the grating effect of fine layer is affected by several factors, but the thickness and its inner layer number are the most predominant factors over others affecting grating effect. 展开更多
关键词 fine thin bed set grating effect frequency response.
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A DFT/ECP-Small Basis Set Modelling of Cisplatin: Molecular Structure and Vibrational Spectrum
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作者 Nicolay I. Dodoff 《Computational Molecular Bioscience》 2012年第2期35-44,共10页
A DFT conformational and vibrational analysis of a single molecule of cisplatin (cis-[Pt(NH3)2Cl2]) was performed by means of PW91 functional and LANL08 ECP basis set for the Pt atom. 3-21G and 3-21G* Basis sets were ... A DFT conformational and vibrational analysis of a single molecule of cisplatin (cis-[Pt(NH3)2Cl2]) was performed by means of PW91 functional and LANL08 ECP basis set for the Pt atom. 3-21G and 3-21G* Basis sets were used for the remaining atoms. All the initially chosen conformations were found to converge to the global minimum conformation of C2v symmetry with H atoms lying in the coordination plane and pointing to the Cl atoms. The computational results were compared with the newest experimental structural data and with the vibrational spectroscopic data for cisplatin, obtained by other workers. The chosen level of theory was found to describe satisfactory the molecular structure (r. m. s. of the relative deviations ≤ 6%) and the harmonic vibrational frequencies (r. m. s. of the relative deviations ≤ 5%) of cisplatin. 展开更多
关键词 CISPLATIN DFT CALCULATIONS BASIS set effective Core Potential Molecular Structure VIBRATIONAL Analysis
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Labetalol versus Hydralazine in the Management of Severe Pre-Eclampsia at Tertiary Hospitals in a Low-Resource Setting: A Randomised Controlled Trial
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作者 Uzoma Otutoaja Adeyemo Olabisi Timothy +7 位作者 Emmanuel Olumide Adewara Olufunmilayo Victoria Adebara Augustine Adebayo Adeniyi Babatunde Sunday Awoyinka Raymond Akujuobi Okere Idowu Oluseyi Adebara Adewumi Bakare Mojisola Olumide Ayankunle 《Open Journal of Obstetrics and Gynecology》 2023年第6期1058-1067,共10页
Objective: Intravenous labetalol and hydralazine are both considered first-line medications for the management of acute-onset, severe hypertension in pregnant and postpartum women. The study compared the efficacy and ... Objective: Intravenous labetalol and hydralazine are both considered first-line medications for the management of acute-onset, severe hypertension in pregnant and postpartum women. The study compared the efficacy and safety profile of intravenous labetalol and hydralazine in the control hypertension in severe pre-eclampsia. Materials and Methods: One hundred patients who presented with severe pre-eclampsia were randomized into two study groups. The fifty patients in each arm of the study received either intravenous labetalol or intravenous hydralazine for the control of blood pressure. Results: The mean age of the labetalol subjects was 28.6 ± 5.47 years while that of their hydralazine counterparts was 29.12 ± 5.77 years. The majority of respondents in both groups were primigravidae (76% vs. 78%) (P = 0.813). The number of doses of drug needed to significantly lower the mean systolic blood pressure was slightly lower in the labetalol group (2 doses) compared to the hydralazine group (5 doses) (t = 0.803<sup>Y</sup>, P = 0.977). The incidence of headaches which were the commonest complaints was comparable in both groups 8% and 10% of respondents respectively (P > 0.05). Conclusion: Although both intravenous labetalol and hydralazine are useful in patients with severe pre-eclampsia, the response to labetalol was better with comparable side effects. 展开更多
关键词 Blood Pressure HYDRALAZINE LABETALOL Low-Resource setting Severe Pre-Eclampsia Side effects
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A Resolution of the Black Hole Information Paradox via Transfinite Set Theory
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作者 Mohamed S. El Naschie 《World Journal of Condensed Matter Physics》 2015年第4期249-260,共12页
A black hole is essentially a relativistic as well as a quantum object. Therefore the information paradox of black holes is a consequence of the clash between these two most fundamental theories of modern physics. It ... A black hole is essentially a relativistic as well as a quantum object. Therefore the information paradox of black holes is a consequence of the clash between these two most fundamental theories of modern physics. It is logical to conclude that a resolution of the problem requires some form of a quantum gravity theory. The present work proposes such a resolution using set theory and pointless spacetime geometry. 展开更多
关键词 Information PARADOX Black HOLES S. Hawking G. 't Hooft L. Susskind Transfinite set Theory NONCOMMUTATIVE Geometry Measure Concentration Dvoretzky’s Theorem DARK Energy CASIMIR effect Nano CASIMIR Reactor
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CET-SET反拨效应指导下英语口语教学任务研究
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作者 钟健儿 《湖北开放职业学院学报》 2020年第12期167-168,共2页
2016年6月,大学英语四、六级考试做了新的调整,其中口语考试变化较大。针对大学英语四、六级考试口语考试新的变化,结合四、六级口语测试环节,本文探讨了该口语测试反拨效应指导下英语口语教学任务的设计及教学实践,以此提升大学生英语... 2016年6月,大学英语四、六级考试做了新的调整,其中口语考试变化较大。针对大学英语四、六级考试口语考试新的变化,结合四、六级口语测试环节,本文探讨了该口语测试反拨效应指导下英语口语教学任务的设计及教学实践,以此提升大学生英语口语能力。 展开更多
关键词 CET-set 反拨效应 英语口语教学 任务设计
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生育的幸福效应——兼论其对低生育率的支撑 被引量:1
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作者 张震 马茜 《人口与经济》 CSSCI 北大核心 2024年第2期44-60,共17页
生育的幸福效应是理解低生育率社会中个体生育决策的一个重要维度。利用中国家庭追踪调查2010—2018年数据,考察孩子出生前后父母幸福感轨迹。研究发现,个人在主观幸福感方面对生育事件有积极的预期收益,主观幸福感在生育事件发生的当... 生育的幸福效应是理解低生育率社会中个体生育决策的一个重要维度。利用中国家庭追踪调查2010—2018年数据,考察孩子出生前后父母幸福感轨迹。研究发现,个人在主观幸福感方面对生育事件有积极的预期收益,主观幸福感在生育事件发生的当年达到顶峰,然后随着时间的推移逐渐下降。生育事件前后的主观幸福感轨迹表明,生育事件对个人的心理和生活感知有积极的促进作用,同时也证实了适应效应的存在。就业性质对生育的幸福效应具有调节作用,并且存在显著的性别差异,表明当父亲和母亲的工作允许他们有更多时间照顾孩子时,他们都会增加亲子互动和沟通并从中获得更高水平的幸福感。生育的这种幸福效应具有超经济性,并借助个人的生育决策筑成低生育率的底部。 展开更多
关键词 主观幸福感 生育的幸福效应 定点理论 母职惩罚 父职惩罚
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基于脊柱稳定性理论下的SET悬吊系统对非特异性下背痛患者的临床应用研究
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作者 徐本磊 龙光峰 +5 位作者 吴焕转 王润协 杨灿乾 伍嘉敏 梁眉眉 袁妙红 《中外医疗》 2022年第34期10-14,19,共6页
目的探讨基于脊柱稳定性理论下的悬吊运动疗法(suspension exercise therapy,SET)悬吊系统对非特异性下背痛患者的临床应用研究。方法随机选取2021年5月-2022年2月在江门市人民医院潮连分院(江门市蓬江区潮连医院临床康复医学)就诊的慢... 目的探讨基于脊柱稳定性理论下的悬吊运动疗法(suspension exercise therapy,SET)悬吊系统对非特异性下背痛患者的临床应用研究。方法随机选取2021年5月-2022年2月在江门市人民医院潮连分院(江门市蓬江区潮连医院临床康复医学)就诊的慢性非特异性下背痛(chronic nonspecific lower back pain,CNLBP)患者100例作为研究对象,随机分为观察组和对照组,各50例,对照组使用常规物理治疗,在此基础上,观察组使用SET悬吊系统治疗,对比两组临床疗效、疼痛及Oswestry功能障碍指数(ODI)、Roland-Morris功能障碍调查表(RMDQ)及功能性动作筛查量表(FMS)、核心区肌肉力量、腰背肌最大肌力。结果观察组治疗有效率为96.00%,明显高于对照组的76.00%,差异有统计学意义(χ^(2)=8.306,P<0.05);观察组治疗1、3个月的VAS疼痛评分、ODI评分明显低于对照组,差异有统计学意义(P<0.05);观察组治疗1、3个月的RMDQ评分明显低于对照组,FMS评分明显高于对照组,差异有统计学意义(P<0.05);观察组治疗3个月的屈、伸、左旋转、右旋转、左侧屈、右侧屈的徒手肌力评定评分明显高于对照组,差异有统计学意义(P<0.05);观察组治疗1个月、3个月以及随访3个月的腰背肌最大肌力明显高于对照组,差异有统计学意义(P<0.05)。结论基于脊柱稳定性理论下的SET悬吊系统对非特异性下背痛患者的临床应用效果显著,能有效改善腰背功能,缓解下背痛,提高腰背肌力及核心区肌肉力量,具有积极的临床意义。 展开更多
关键词 非特异性下背痛 脊柱稳定性理论 set悬吊系统 临床效果
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雷电间接效应多重脉冲组电流产生装置的设计
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作者 刘宏伟 栾崇彪 +3 位作者 袁建强 肖金水 黄宇鹏 王凌云 《强激光与粒子束》 CAS CSCD 北大核心 2024年第2期1-7,共7页
针对雷电间接效应多重脉冲组电流模拟需求,完成了雷电间接效应多重脉冲组模拟源的设计,采用20个Crowbar电路支路,通过分时放电的方式实现1个脉冲串内多脉冲输出需求,每个支路可以实现最小间隔30 ms的重复频率放电,从而实现3个脉冲串的... 针对雷电间接效应多重脉冲组电流模拟需求,完成了雷电间接效应多重脉冲组模拟源的设计,采用20个Crowbar电路支路,通过分时放电的方式实现1个脉冲串内多脉冲输出需求,每个支路可以实现最小间隔30 ms的重复频率放电,从而实现3个脉冲串的输出需求。对放电支路的参数进行了详细设计,分析了电容、波尾电路电感、波尾电路电阻参数变化对输出特性的影响。分析了采用并联大电容实现放电电容重复频率快速充电的可行性,完成了装置的初步结构设计并结合装置结构简要分析了电路模拟参数设置的合理性。该装置建成后,可为电子、电气设备等开展测试提供技术支持。 展开更多
关键词 雷电间接效应 多重脉冲组(H波) 雷电模拟源 冲击电流发生器
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饮食类非遗产品网络营销影响因素的组态及提升路径 被引量:1
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作者 刘旭玲 刘佳婕 +2 位作者 刘世豪 冯佳悦 王鋆峥 《美食研究》 北大核心 2024年第2期23-31,共9页
随着互联网技术的迅猛发展,短视频、直播等众多新兴媒介兴起并普及,这为非物质文化遗产的保护和传承提供了新动能,促进了非遗产品的网络营销。以80个国家级饮食类非遗产品为样本,运用模糊集定性比较分析法,剖析网络搜索量、短视频传播... 随着互联网技术的迅猛发展,短视频、直播等众多新兴媒介兴起并普及,这为非物质文化遗产的保护和传承提供了新动能,促进了非遗产品的网络营销。以80个国家级饮食类非遗产品为样本,运用模糊集定性比较分析法,剖析网络搜索量、短视频传播效果、店铺经营年限、粉丝数量以及好评率等因素对网络销量的影响。研究发现,不论是对于高水平还是低水平的网络营销效果,都不存在解释其结果的单一必要条件。饮食类非遗产品高销量存在4种组态,低销量存在3种组态,且高/低销量产生的组态呈非对称关系。其中,短视频传播效果、店铺粉丝数量和好评率在高/低销量产生过程中的作用突出。不同饮食类非遗产品可根据自身条件禀赋,着力于多因素的联动适配,以实现高销量的网络营销效果。 展开更多
关键词 饮食类非遗产品 网络营销 模糊集定性比较分析 组态效应
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基于改进FMEA的污水厂设备故障风险评估模型
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作者 刘新 伍俊楠 +3 位作者 潘殿琦 张以晨 张继权 柯楷 《中国安全科学学报》 CAS CSCD 北大核心 2024年第8期101-107,共7页
为保障污水处理厂正常运行,预防厂内设备发生故障,提出一种改进的故障模式与影响分析(FMEA)的风险评估模型。首先采用FMEA法识别污水厂设备故障模式,并结合毕达哥拉斯模糊集(PFS)刻画不确定评估信息;其次利用逐步权重评估比率分析法(SWA... 为保障污水处理厂正常运行,预防厂内设备发生故障,提出一种改进的故障模式与影响分析(FMEA)的风险评估模型。首先采用FMEA法识别污水厂设备故障模式,并结合毕达哥拉斯模糊集(PFS)刻画不确定评估信息;其次利用逐步权重评估比率分析法(SWARA)和最大偏差法计算主客观权重,通过博弈论组合权重计算3个风险因子的综合权重;然后采用多目标优化比率分析法(MOORA)对设备故障模式进行风险排序。最后以长春市Z污水厂设备故障风险评估为例,并将所提模型与传统FMEA、毕达哥拉斯模糊(PF)-优劣解距离法(TOPSIS)和PF-妥协折衷排序法(PF-VIKOR)等方法对比,验证该模型的有效性。结果表明:污水厂设备故障模式前3位是除砂机抽取的砂浆所含有机物过多、膜片脱落或破裂和大块异物进入水泵。 展开更多
关键词 污水厂 故障模式与影响分析(FMEA) 设备故障 风险评估 毕达哥拉斯模糊集(PFS)
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