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Comprehensive effects of traditional Chinese medicine treatment on heart failure and changes in B-type natriuretic peptide levels: A meta-analysis
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作者 Li-Li Xia Shu-Yun Yang +2 位作者 Jun-Yao Xu Han-Qing Chen Zhu-Yuan Fang 《World Journal of Clinical Cases》 SCIE 2024年第4期766-776,共11页
BACKGROUND Heart failure(HF),a common cardiovascular condition,is characterized by significant morbidity and mortality.While traditional Chinese medicine(TCM)is often used as a complementary approach in HF management,... BACKGROUND Heart failure(HF),a common cardiovascular condition,is characterized by significant morbidity and mortality.While traditional Chinese medicine(TCM)is often used as a complementary approach in HF management,systematic evalua-tions of its impact on clinical outcomes,TCM syndrome scores,and B-type natriuretic peptide(BNP)levels are lacking.This study fills this gap through a comprehensive analysis of randomized controlled trials(RCTs)focusing on TCM for HF treatment.It encompasses an assessment of methodological quality,a meta-analysis,and an evaluation of evidence quality based on established standards.The results offer crucial insights into the potential advantages and constraints of TCM in HF management.RCTs on TCM for HF treatment published since the establishment of the database were searched in four Chinese and English databases,including China National Knowledge Infrastructure,Wanfang,VIP Information Chinese Science and Technology Journal,and PubMed.Methodological quality was assessed for the included studies with the Cochrane risk-of-bias assessment tool,and the meta-analysis and publication bias assessment was performed with the RevMan5.3 software.Finally,the quality of evidence was rated according to the GRADE criteria.RESULTS A total of 1098 RCTs were initially retrieved.After screening,16 RCTs were finally included in our study,which were published between 2020 and 2023.These RCTs involved 1660 HF patients,including 832 in the TCM group[TCM combined with conventional Western medicine(CMW)treatment]and 828 in the CWM group(CWM treatment).The course of treatments varied from 1 wk to 3 months.TCM syndrome differentiation was analyzed in 11 of the included RCTs.In all included RCTs,outcome indicators included comprehensive clinical outcomes,TCM syndrome scores,and BNP levels.The meta-analysis results showed significant differences between the TCM and CWM groups in terms of comprehensive clinical outcomes[risk ratio=-0.54;95%confidence interval(CI)=-0.61,-0.47;P<0.00001],TCM syndrome scores[weighted mean difference(WMD)=-142.07;95%CI=-147.56,-136.57;P<0.00001],and BNP levels(WMD=-142.07;95%CI=-147.56,-136.57;P<0.00001).According to the GRADE criteria,RCTs where"TCM improves clinical comprehensive outcomes"were rated as low-quality evidence,and RCTs where"TCM reduces TCM syndrome scores"or"TCM decreases BNP levels"were rated as medium-quality evidence.CONCLUSION TCM combined with CWM treatment effectively improves comprehensive clinical outcomes and diminishes TCM syndrome scores and BNP levels in HF patients.Given the low and medium quality of the included RCTs,the application of these results should be cautious. 展开更多
关键词 Traditional Chinese medicine Heart failure Comprehensive clinical outcomes Traditional Chinese medicine syndrome score B-type natriuretic peptide level Meta-analysis©The Author(s)2024.Published by Baishideng Publishing Group Inc.
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Exploring Variability in Sea Level at a Tide Gauge Station through Control Charts
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作者 H.Bâkiİz 《Journal of Environmental & Earth Sciences》 CAS 2024年第1期11-18,共8页
Monitoring temporal changes in sea level is important in assessing coastal risk.Sea level anomalies at a tide gauge station,if kinematically conceived,include systematic variations such as trend,acceleration,periodic ... Monitoring temporal changes in sea level is important in assessing coastal risk.Sea level anomalies at a tide gauge station,if kinematically conceived,include systematic variations such as trend,acceleration,periodic oscillations,and random disturbances.Among them,the non-stationary nature of the random sea level variations of known or unknown origin at coastal regions has been long recognized by the sea level community.This study proposes the analyses of subgroups of random residual statistics of a rigorously formulated kinematic model solution of tide gauge variations using X-bar and S control charts.The approach is demonstrated using Key West,Florida tide gauge records.The mean and standard errors of 5-year-long subgroups of the residuals revealed that sea level changes at this location have been progressively intensifying from 1913 to the present.Increasing oscillations in sea level at this locality may be attributed partly to the thermal expansion of seawater with increasing temperatures causing larger buoyancy-related sea level fluctuations as well as the intensification of atmospheric events including wind patterns and the impact of changes in inverted barometer effects that will alter coastal risk assessments for the future. 展开更多
关键词 Climate change sea level variance X-bar s control charts
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Nucleoside diphosphate-linked moiety X-type motif 15 R139C genotypes impact 6-thioguanine nucleotide cut-off levels to predict thiopurine-induced leukopenia in Crohn’s disease patients 被引量:4
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作者 Xia Zhu Kang Chao +7 位作者 Miao Li Wen Xie Hong Zheng Jin-Xin Zhang Pin-Jin Hu Min Huang Xiang Gao Xue-Ding Wang 《World Journal of Gastroenterology》 SCIE CAS 2019年第38期5850-5861,共12页
BACKGROUND Thiopurine-induced leukopenia(TIL)is a life-threatening toxicity and occurs with a high frequency in the Asian population.Although nucleoside diphosphate-linked moiety X-type motif 15(NUDT15)variants signif... BACKGROUND Thiopurine-induced leukopenia(TIL)is a life-threatening toxicity and occurs with a high frequency in the Asian population.Although nucleoside diphosphate-linked moiety X-type motif 15(NUDT15)variants significantly improve the predictive sensitivity of TIL,more than 50%of cases of this toxicity cannot be predicted by this mutation.The potential use of the 6-thioguanine nucleotide(6TGN)level to predict TIL has been explored,but no decisive conclusion has been reached.Can we increase the predictive sensitivity based on 6TGN by subgrouping patients according to their NUDT15 R139C genotypes?AIM To determine the 6TGN cut-off levels after dividing patients into subgroups according to their NUDT15 R139C genotypes.METHODS Patients’clinical and epidemiological characteristics were collected from medical records from July 2014 to February 2017.NUDT15 R139C,thiopurine S methyltransferase,and 6TGN concentrations were measured.RESULTS A total of 411 Crohn’s disease patients were included.TIL was observed in 72 individuals with a median 6TGN level of 323.4 pmol/8×10^8 red blood cells(RBC),which was not different from that of patients without TIL(P=0.071).Then,we compared the 6TGN levels based on NUDT15 R139C.For CC(n=342)and CT(n=65)genotypes,the median 6TGN level in patients with TIL was significantly higher than that in patients without(474.8 vs 306.0 pmol/8×10^8 RBC,P=9.4×10-^5;291.7 vs 217.6 pmol/8×10^8 RBC,P=0.039,respectively).The four TT carriers developed TIL,with a median 6TGN concentration of 135.8 pmol/8×10^8 RBC.The 6TGN cut-off levels were 411.5 and 319.2 pmol/8×108 RBC for the CC and CT groups,respectively.CONCLUSION The predictive sensitivity of TIL based on 6TGN is dramatically increased after subgrouping according to NUDT15 R139C genotypes.Applying 6TGN cut-off levels to adjust thiopurine therapies based on NUDT15 is strongly recommended. 展开更多
关键词 Crohn’s disease Thioguanine NUCLEOTIDE levels NUCLEOsIDE diphosphatelinked MOIETY X-type MOTIF 15 Thiopurine-induced LEUKOPENIA
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The Quantum Condition That Should Have Been Assumed by Bohr When Deriving the Energy Levels of a Hydrogen Atom 被引量:2
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作者 Koshun Suto 《Journal of Applied Mathematics and Physics》 2021年第6期1230-1244,共15页
Bohr assumed a quantum condition when deriving the energy levels of a hydrogen atom. This famous quantum condition was not derived logically, but it beautifully explained the energy levels of the hydrogen atom. Theref... Bohr assumed a quantum condition when deriving the energy levels of a hydrogen atom. This famous quantum condition was not derived logically, but it beautifully explained the energy levels of the hydrogen atom. Therefore, Bohr’s quantum condition was accepted by physicists. However, the energy levels predicted by the eventually completed quantum mechanics do not match perfectly with the predictions of Bohr. For this reason, it cannot be said that Bohr’s quantum condition is a perfectly correct assumption. Since the mass of an electron which moves inside a hydrogen atom varies, Bohr’s quantum condition must be revised. However, the newly derived relativistic quantum condition is too complex to be assumed at the beginning. The velocity of an electron in a hydrogen atom is known as the Bohr velocity. This velocity can be derived from the formula for energy levels derived by Bohr. The velocity <em>v </em>of an electron including the principal quantum number <em>n</em> is given by <em>αc</em>/<em>n</em>. This paper elucidates the fact that this formula is built into Bohr’s quantum condition. It is also concluded in this paper that it is precisely this velocity formula that is the quantum condition that should have been assumed in the first place by Bohr. From Bohr’s quantum condition, it is impossible to derive the relativistic energy levels of a hydrogen atom, but they can be derived from the new quantum condition. This paper proposes raising the status of the previously-known Bohr velocity formula. 展开更多
关键词 Relativistic Energy levels of the Hydrogen Atom Bohr’s Quantum Condition Bohr Velocity Einstein’s Energy-Momentum Relationship suto’s Energy-Momentum Relationship Relativistic Kinetic Energy
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基于Swanson关怀理论的护理干预在早产儿母亲中的应用
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作者 黄丽玲 林梅 +5 位作者 黄芝蓉 许冬梅 黄婷 王嘉莹 马妮妮 李玉娟 《全科护理》 2024年第8期1459-1464,共6页
目的:探讨以Swanson关怀理论为框架的护理干预在早产儿母亲中的应用效果。方法:采取便利抽样法选取2022年1月-5月入住百色市某三级甲等医院新生儿重症监护室(NICU)治愈出院的40例早产儿母亲作为对照组,选取2022年6月-10月入住百色市某... 目的:探讨以Swanson关怀理论为框架的护理干预在早产儿母亲中的应用效果。方法:采取便利抽样法选取2022年1月-5月入住百色市某三级甲等医院新生儿重症监护室(NICU)治愈出院的40例早产儿母亲作为对照组,选取2022年6月-10月入住百色市某三级甲等医院NICU治愈出院的40例早产儿母亲作为试验组。对照组实施NICU常规护理,试验组在对照组干预的基础上实施基于Swanson关怀理论的护理干预,比较两组早产儿母亲干预前后疾病不确定感、希望水平、育儿胜任感得分情况。结果:干预后试验组早产儿母亲疾病不确定感得分明显低于对照组(P<0.001),希望水平得分明显高于对照组(P<0.001);出院时及出院1个月后试验组早产儿母亲育儿胜任感得分明显高于对照组(P<0.001)。结论:基于Swanson关怀理论的护理干预可有效降低早产儿母亲疾病不确定感水平,提高其希望水平,增强其育儿胜任感,有利于早产儿顺利从医院过渡至家庭。 展开更多
关键词 swanson关怀理论 早产儿母亲 疾病不确定感 希望水平 育儿胜任感量表
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乌什M_(S)7.1地震引起新55井、新46井水位水温同震响应分析
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作者 贾永斌 闫玮 +1 位作者 祖丽皮牙·艾尼瓦尔 汪成国 《内陆地震》 2024年第2期158-165,共8页
为研究乌什M_(S)7.1地震引起新55井、新46井水位不同程度的响应变化,对比分析观测井水位的同震响应特征,从含水层渗透性变化和地震波能量密度探讨了同震响应机理。结果表明:①伽师新55井和乌什新46井同震响应形态主要表现为井水位的大... 为研究乌什M_(S)7.1地震引起新55井、新46井水位不同程度的响应变化,对比分析观测井水位的同震响应特征,从含水层渗透性变化和地震波能量密度探讨了同震响应机理。结果表明:①伽师新55井和乌什新46井同震响应形态主要表现为井水位的大幅快速上升。②固体潮计算分析结果表明当地震波作用于新55井和新46井时,前者垂向水力交换增强,水平向水力交换减弱,含水层的水与井水进行交换,引起井水位同震上升变化;后者含水层渗透性增加,含水层水与井水进行交换,引起井水位同震上升变化。③地震能量密度计算结果显示新55井比新46井容易触发同震响应,这种差异性的响应可能与井含水层岩性有关。 展开更多
关键词 乌什M_(s)7.1地震 新55井 新46井 水位水温 同震响应
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In-doping collaboratively controlling back interface and bulk defects to achieve efficient flexible CZTSSe solar cells
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作者 Quanzhen Sun Yifan Li +6 位作者 Caixia Zhang Shunli Du Weihao Xie Jionghua Wu Qiao Zheng Hui Deng Shuying Cheng 《Journal of Energy Chemistry》 SCIE EI CAS CSCD 2024年第2期10-17,I0002,共9页
Focusing on the low open circuit voltage(V_(OC))and fill factor(FF)in flexible Cu_(2)ZnSn(S,Se)_(4)(CZTSSe)solar cells,indium(In)ions are introduced into the CZTSSe absorbers near Mo foils to modify the back interface... Focusing on the low open circuit voltage(V_(OC))and fill factor(FF)in flexible Cu_(2)ZnSn(S,Se)_(4)(CZTSSe)solar cells,indium(In)ions are introduced into the CZTSSe absorbers near Mo foils to modify the back interface and passivate deep level defects in CZTSSe bulk concurrently for improving the performance of flexible device.The results show that In doping effectively inhibits the formation of secondary phase(Cu(S,Se)_(2))and VSndefects.Further studies demonstrate that the barrier height at the back interface is decreased and the deep level defects(Cu_(Sn)defects)in CZTSSe bulk are passivated.Moreover,the carrier concentration is increased and the V_(OC) deficit(V_(OC,def))is decreased significantly due to In doping.Finally,the flexible CZTSSe solar cell with 10.01%power conversion efficiency(PCE)has been obtained.The synergistic strategy of interface modification and bulk defects passivation through In incorporation provides a new thought for the fabrication of efficient flexible kesterite-based solar cells. 展开更多
关键词 Flexible solar cells Cu_(2)Znsn(s se)_(4) Back interface Deep level defects Barrier height
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Effects of Physical Activity Levels on Fatigue Perception in Patients with Parkinson’s Disease and Neurologically Healthy Individuals
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作者 Paulo Cezar Rocha dos Santos Fabio Augusto Barbieri +2 位作者 Diego Orcioli-Silva Lucas Simieli Lilian Teresa Bucken Gobbi 《Health》 2014年第21期2927-2933,共7页
Background: Recent researches involving fatigue and Parkinson’s disease (PD) sought to verify its incidence and the impacts of fatigue on quality life of patients with PD. Despite the importance of regular physical a... Background: Recent researches involving fatigue and Parkinson’s disease (PD) sought to verify its incidence and the impacts of fatigue on quality life of patients with PD. Despite the importance of regular physical activity practice, there are only few studies that verified the influence of the levels of physical activity on fatigue in patients with PD. Objective: The aim of this study was to compare perception of fatigue between individuals with PD and neurologically healthy individuals (control group), considering the physical activity levels;and to verify the relation between physical activity levels and fatigue dimensions for individuals with PD and control group. Methods: Eighty individuals (40 patients with PD and 40 control individuals) participated in this study. Physical activity levels were evaluated through Modified Baecke Questionnaire for Older Adults. Multidimensional Fatigue Inventory (MFI) was used in order to evaluate fatigue dimensions (general, physical and mental fatigue, reduced motivation and activity). MANOVA two-way and Pearson linear correlation test were performed to analyze the data. Results: Patients with PD presented higher levels of fatigue, in all dimensions evaluated by MFI, comparing to control individuals. There was no association between physical activity levels and perception of fatigue for patients with PD and control individuals. Conclusion: Patients with PD showed increased perception of fatigue when compared to control individuals, due to PD characteristics. In addition, the perception of fatigue’s symptom was not influenced and had no relation by the level of physical activity. 展开更多
关键词 Parkinson’s Disease sYMPTOM of FATIGUE Physical Activity levels NON-MOTOR sYMPTOM
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Algebraic Study of the Vibrational Levels and Potential Energy Surface of the Excited Electronic State (C^1A') for S2O
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作者 Xiao-yan Wang Shi-liang Ding +2 位作者 Jin-dong Xie Peng-cheng Wang Wei-gang Zhong 《Chinese Journal of Chemical Physics》 SCIE CAS CSCD 北大核心 2006年第1期43-46,共4页
The vibrational levels and potential energy surface of a stable structure for S2O in the excited electronic states C^1A' were carried out with algebraic method. The vibrational spectra were obtained (with total quan... The vibrational levels and potential energy surface of a stable structure for S2O in the excited electronic states C^1A' were carried out with algebraic method. The vibrational spectra were obtained (with total quantum number v=20) by fitting 30 spectra data. The fitted rms(root mean square) error based on the Hamiltonian witb 9 parameters was 2.40 cm^-1. The dissociation energy and force constant were also determined by the analytical potential energy surface. The method is proved to be effective by comparing these results with the experimental data. 展开更多
关键词 s2O3 Energy level Potential energy surface
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超高效液相色谱-串联质谱法测定大鼠尿液中双酚S内暴露水平
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作者 陈璐 杨顺益 +2 位作者 王勖 胡廷皓 罗宏伟 《实验室检测》 2024年第4期12-16,共5页
目的建立不同剂量双酚S(Bisphenol S,BPS)暴露动物实验模型,分析大鼠尿液中BPS内暴露水平的动态变化。方法通过灌胃给药建立对照组、1μg/kg低剂量组、100μg/kg中剂量组和10 mg/kg高剂量组Sprague Dawley(SD)大鼠暴露模型,使用超高效... 目的建立不同剂量双酚S(Bisphenol S,BPS)暴露动物实验模型,分析大鼠尿液中BPS内暴露水平的动态变化。方法通过灌胃给药建立对照组、1μg/kg低剂量组、100μg/kg中剂量组和10 mg/kg高剂量组Sprague Dawley(SD)大鼠暴露模型,使用超高效液相色谱-串联质谱法(Ultra High Performance Liquid Chromatography Tandem Mass Spectrometry,UPLC-MS/MS)内标法检测大鼠在连续6周暴露不同剂量BPS后其尿样中BPS含量的变化。结果目标物BPS在0.2~100μg/L的范围内呈良好线性关系,r^(2)≥0.998,方法检出限为0.01μg/L,定量限为0.03μg/L。对大鼠尿液的检测结果表明,随着暴露时间的增加,BPS在各剂量组大鼠体内的生物累积效应明显,尿液中BPS的内暴露水平在给药的6周中持续升高,且从给药后的第一周开始,尿液BPS含量的组间差异均有统计学意义(P<0.05)。结论本研究成功建立了不同剂量BPS暴露的SD大鼠动物实验模型,准确测定了大鼠连续6周尿液中双酚S的内暴露水平,为BPS毒理学剂量-效应关系研究提供参考。 展开更多
关键词 双酚s 尿液 超高效液相色谱-串联质谱法(UPLC-Ms/Ms) 暴露水平
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Filipin Levels as Potential Predictors of Alzheimer’s Disease Risk
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作者 Michael A. Castello Kristy D. Howard +1 位作者 Arthur J. Castaneda Salvador Soriano 《Advances in Alzheimer's Disease》 2014年第3期137-144,共8页
To date, therapies to prevent or treat Alzheimer’s disease (AD) have largely focused on removing excess aggregation-prone amyloid peptide Aβ from the brain, an approach that has produced disappointing clinical outco... To date, therapies to prevent or treat Alzheimer’s disease (AD) have largely focused on removing excess aggregation-prone amyloid peptide Aβ from the brain, an approach that has produced disappointing clinical outcomes. An alternative hypothesis proposes that Aβ production and aggregation is a symptom of a larger, systemic disease affecting the regulation of lipids, including cholesterol. In this scenario, lipid dysregulation would likely occur early in the disease process, making it an ideal target for predicting risk of mild cognitive impairment (MCI) to AD conversion. Here, we report that levels of filipin, a fluorescent polyene macrolide widely used as a diagnostic tool for diseases of lipid dysregulation, correlate with cellular damage caused by 27-hydroxycholesterol and with dementia status in human peripheral blood cells. These results provide strong preliminary data suggesting that filipin could be of use in the development of a quick and inexpensive method to measure the risk of AD conversion in patients with MCI, supplementing existing testing strategies that focus on the consequences of Aβ accumulation. 展开更多
关键词 Alzheimer’s Disease Lipid DYsREGULATION CHOLEsTEROL Mild Cognitive IMPAIRMENT FILIPIN levels
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Charged Particle in a Flat Box with Static Electromagnetic Field and Landau’s Levels
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作者 Gustavo V. López Jorge A. Lizarraga 《Journal of Modern Physics》 2020年第10期1731-1742,共12页
We study the quantization of a charged particle motion without spin inside a flat box under a static electromagnetic field. Contrary to Landau’s solution with constant magnetic field transverse to the box and using F... We study the quantization of a charged particle motion without spin inside a flat box under a static electromagnetic field. Contrary to Landau’s solution with constant magnetic field transverse to the box and using Fourier transformation, we found a full solution for the wave function which is different from that one given by Landau, and this fact remains when static electric field is added. However, the Landau’s levels appear in all cases. 展开更多
关键词 Landau’s levels Quantum Hall Effect Flat Box
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基于S-XGBoost融合模型的中国进境快件风险水平评价研究
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作者 刘昌伟 谢晶 +2 位作者 邹廉青 梅云鹏 Kashif Abbass 《海关与经贸研究》 2024年第1期48-61,共14页
党的二十大报告指出要增强维护国家安全能力,推进国家安全体系和能力现代化,坚决维护国家安全和社会稳定。随着互联网产业的发展壮大,以进境快件为代表的跨境个人消费进入发展的快车道,随之而来的安全准入风险也越来越高。为深入推进智... 党的二十大报告指出要增强维护国家安全能力,推进国家安全体系和能力现代化,坚决维护国家安全和社会稳定。随着互联网产业的发展壮大,以进境快件为代表的跨境个人消费进入发展的快车道,随之而来的安全准入风险也越来越高。为深入推进智慧海关建设,进一步提升进境快件风险防控能力,文章分析了现行监管模式下进境快件存在的问题,运用XGBoost算法和SMOTE技术构建了S-XGBoost进境快件风险评估模型,并对历史通关数据进行了仿真布控和评估。研究结果表明本文提出的S-XGBoost算法模型具有较好的预测效果,风险预测准确率达到了99.06%,能够为海关工作人员提升进境快件布控有效率提出切实参考建议。 展开更多
关键词 数据挖掘 中国进境快件 s-XGBoost 风险水平
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Effective Face-to-faceTutorials of Online English Learning Lie in Interaction of Affective Domain and Higher Levels of Cognitive Domain of Bloom's Taxonomy
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作者 Jiali Ding 《Sino-US English Teaching》 2004年第2期39-50,共12页
Online English learning as an outcome of the rapid development of the Internet has got a wider and wider market in China. However, problems of varieties have also occurred along its way. People never stop thinking of ... Online English learning as an outcome of the rapid development of the Internet has got a wider and wider market in China. However, problems of varieties have also occurred along its way. People never stop thinking of better strategies either in designing online course wares or tutorials to help smooth the learning process. My experience as a tutor is that interaction of affective domain and higher levels of cognitive domain of Bloom's Taxonomy plays an important role in face-to-face tutorials of online English learning. 展开更多
关键词 online English learning face-to-face tutorials Bloom's Taxonomy of educational objectives Affective Domain higher levels of Cognitive Domain
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用Level Set方法求解具有自由面的流动问题 被引量:11
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作者 袁德奎 陶建华 《力学学报》 EI CSCD 北大核心 2000年第3期264-271,共8页
为采用 Level Set方法来计算有自由水面的流动问题提出了一种方案.把自由水面视为水和空气的交界面,两种介质用统一的N-S方程求解,在自由面两侧分别采用各自的密度和粘性,并在自由面上给以适当的光滑;采用边界无法求解... 为采用 Level Set方法来计算有自由水面的流动问题提出了一种方案.把自由水面视为水和空气的交界面,两种介质用统一的N-S方程求解,在自由面两侧分别采用各自的密度和粘性,并在自由面上给以适当的光滑;采用边界无法求解双调和方程来确定距离函数;N-S方程用投影法求解.文中给出了二维水池水面振荡和瞬时溃坝问题的算例,可以看出用 Level Set方法求解有自由面流动问题是有效的. 展开更多
关键词 level sET方法 自由面 N-s方程 流动 水动力学
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用LEVEL SET方法计算溃坝波的传播过程 被引量:5
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作者 陶建华 谢伟松 《水利学报》 EI CSCD 北大核心 1999年第10期17-22,共6页
溃坝波的数值模拟在于正确地计算坝体溃决后上下游水面的迅速变化过程. 本文研究了近年发展起来的求解两种流体界面的Level Set 方法及其在具有自由表面的水动力学问题中的应用. 对不同底坡上的二维溃坝波进行了计算, 取得... 溃坝波的数值模拟在于正确地计算坝体溃决后上下游水面的迅速变化过程. 本文研究了近年发展起来的求解两种流体界面的Level Set 方法及其在具有自由表面的水动力学问题中的应用. 对不同底坡上的二维溃坝波进行了计算, 取得了和实验资料符合良好的结果. 展开更多
关键词 levelset方法 自由表面 溃坝波 Ns方程
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快速粒子level set方法的并行化
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作者 黄筱云 夏波 +1 位作者 程永舟 赵利平 《哈尔滨工程大学学报》 EI CAS CSCD 北大核心 2018年第9期1478-1484,共7页
为缩短快速粒子level set(FPLS)方法追踪交界面的时间,分别运用区域分解和粒子分解算法来减少欧拉计算(level set对流方程和重新初始化)和拉格朗日计算(粒子时程积分和误差校正)的开销。算法采用OpenMP技术来实现,并通过Zalesak圆盘、... 为缩短快速粒子level set(FPLS)方法追踪交界面的时间,分别运用区域分解和粒子分解算法来减少欧拉计算(level set对流方程和重新初始化)和拉格朗日计算(粒子时程积分和误差校正)的开销。算法采用OpenMP技术来实现,并通过Zalesak圆盘、单涡以及三维变形等典型算例进行验证。计算结果表明:4线程下加速比能超过2,8线程下加速比也能接近4,并行化的FPLS方法具有良好的实用性和可扩展性。 展开更多
关键词 快速粒子level sET方法 并行 区域分解 粒子分解 OPENMP Zalesak圆盘 单涡
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2022年门源M_(S)6.9地震前后垂直形变
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作者 张四新 郝明 +1 位作者 贾鹏 侯伯文 《地震地磁观测与研究》 2023年第S01期240-242,共3页
1研究背景据中国地震台网测定2022年1月8日1时45分,青海省海北州门源县发生M_(S)6.9地震(37.77°N,101.26°E),震源深度为10 km,这是继1986年8月26日门源M_(S)6.4地震(37.70°N,101.50°E)和2016年1月21日门源M_(S)6.4... 1研究背景据中国地震台网测定2022年1月8日1时45分,青海省海北州门源县发生M_(S)6.9地震(37.77°N,101.26°E),震源深度为10 km,这是继1986年8月26日门源M_(S)6.4地震(37.70°N,101.50°E)和2016年1月21日门源M_(S)6.4地震(37.68°N,101.62°E)之后该区域发生的又一次6级以上强震。 展开更多
关键词 2022年门源M_(s)6.9地震 跨断裂水准 垂直形变 童子坝水准 大梁水准
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RELATIVE SEA LEVEL RISE AND ITS EFFECTS ON ENVIRONMENT AND RESOURCES IN CHINAS COASTAL AREAS 被引量:2
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作者 杨桂山 《Chinese Geographical Science》 SCIE CSCD 1995年第2期104-115,共12页
Due to global climate warming and natural and man-made land subsidence etc., relative sea level rise in the coastal plains of China will exceed 2-3 times over the golbal mean value during the first half part of the 21... Due to global climate warming and natural and man-made land subsidence etc., relative sea level rise in the coastal plains of China will exceed 2-3 times over the golbal mean value during the first half part of the 21st century. It will result in a series of adverse impacts on evolution of natural environment and socioeconomic development of the coastal area. This paper analyses environmental and resource effects induced by relative sea level rise in China's coastal areas on the basis of rough estimate of future relative sea level rise. These effects include inundating tidal flat and wetlands and increase in inundated risk of coastal habitable land,exacerbating storm surge. coastal erosion, flooding and salt water intrusion hazards.as well as endangering land. water. tourism and living resources and their utilization. 展开更多
关键词 China’s COAsTAL areas. RELATIVE sEA level RIsE environmental effect resource effect
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Atomic level deposition to extend Moore’s law and beyond 被引量:9
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作者 Rong Chen Yi-Cheng Li +2 位作者 Jia-Ming Cai Kun Cao Han-Bo-Ram Lee 《International Journal of Extreme Manufacturing》 2020年第2期29-52,共24页
In the past decades,Moore’s law drives the semiconductor industry to continuously shrink the critical size of transistors down to 7 nm.As transistors further downscaling to smaller sizes,the law reaches its limitatio... In the past decades,Moore’s law drives the semiconductor industry to continuously shrink the critical size of transistors down to 7 nm.As transistors further downscaling to smaller sizes,the law reaches its limitation,and the increase of transistors density on the chip decelerates.Up to now,extreme ultraviolet lithography has been used in some key steps,and it is facing alignment precision and high costs for high-volume manufacturing.Meanwhile,the introduction of new materials and 3D complex structures brings serious challenges for top-down methods.Thus,bottom-up schemes are believed to be necessary methods combined with the top-down processes.In this article,atomic level deposition methods are reviewed and categorized to extend Moore’s law and beyond.Firstly,the deposition brings lateral angstrom resolution to the vertical direction as well as top-down etching,such as double patterning,transfer of nanowires,deposition of nanotubes,and so on.Secondly,various template-assisted selective deposition methods including dielectric templates,inhibitors and correction steps have been utilized for the alignment of 3D complex structures.Higher resolution can be achieved by inherently selective deposition,and the underlying selective mechanism is discussed.Finally,the requirements for higher precision and efficiency manufacturing are also discussed,including the equipment,integration processes,scale-up issues,etc.The article reviews low dimensional manufacturing and integration of 3D complex structures for the extension of Moore’s law in semiconductor fields,and emerging fields including but not limited to energy,catalysis,sensor and biomedicals. 展开更多
关键词 Moore’s law atomic level deposition high resolution selective deposition ALIGNMENT
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