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1. chinaXiv:202109.00068 [pdf]

Fluidic Endogenous Magnetism and Magnetic Monopole Clues from Liquid Metal Droplet Machine

Zhou, Ying-Xin; Zu, Jia-Sheng; Liu, Jing
Comment:31 Pages, 14 Figures
Subjects: Physics >> Electromagnetism, Optics, Acoustics, Heat Transfer, Classical Mechanics, and Fluid Dynamics

磁和磁单极子是物理学中的经典问题。传统磁体通常由刚性材料组成,在回答极端问题时可能面临挑战。这里,我们首次从不同于刚性磁体的导电性流体物质出发,提出通过调控液态金属机器来产生流态化内生磁性并由此构造磁单极子。基于理论解释和概念性实验证据,我们阐明了当溶液中的镓基液态金属在电驱动下发生旋转时,其内部会形成一个内生磁场,这很好地解释了两个这样分离的金属液滴能很容易融合在一起的实验现象,原因在于二者通过各自对应的N极和S极相互吸引。此外,我们还阐明了自驱动型液态金属机器也以一种内生流态化磁体出现且具有电磁同源性;当溶液中的液态镓吞食铝时,会形成一个旋转马达和在体动态变化的电荷分布,从而在内部产生内生磁性;这就解释了运动中的液态金属马达之间经常发生反射性碰撞和吸引性融合的现象,这两种现象分别是由于马达之间N极和S极的动态调整引起的。最后,我们设想可通过这种流态化内生磁体制造磁单极子,并提出了实现这一目标的四条技术路线:1. 匹配液态金属机器的内部流场;2. 基于外电场效应与磁场的叠加效应;3. 借助磁颗粒与液态金属马达之间的复合结构;4. 化学途径,如通过原电池反应。总的来说,本文理论和提供的实验证据揭示了液态金属机器作为流体型内生磁体的机制,并指出了实现磁单极的一些有希望的途径。在不久的将来,在此基础上建立一些非传统型磁电器件和应用是可能的。

submitted time 2021-09-27 Hits3308Downloads292 Comment 1

2. chinaXiv:202109.00056 [pdf]

接种还是不接种疫苗?一项对待不确定性“趋避冲突”的态度调查

杜思源; 戴亦馨; 李佩威; 赵宁; 李纾; 郑昱
Subjects: Psychology >> Applied Psychology

[目的] 测量民众接种新冠病毒疫苗的真实意愿与常规态度调查方法所测出来的接种意愿的差异。 [方法] 我们于2021年1月22日至27日调查了全国30个省/市/自治区(除西藏自治区)共3123人对接种新冠病毒疫苗(以下简称疫苗)的意愿。 [结果] 在我国接种疫苗的早期,民众对接种疫苗的意愿并不如预期般乐观,被调查人群中选择“现在不接种”和“观望后再决定”的人数超过了半数。 [结论] 研究者应慎重选择调查民众疫苗接种真实意愿的调查方法,建议相关部门要对民众的“接种迟疑”有充分的预判和准备。

submitted time 2021-09-24 Hits4986Downloads272 Comment 1

3. chinaXiv:202108.00039 [pdf]

干旱内陆区声波干预下降雨微物理特征研究

潘佩翀; 时洋
Subjects: Geosciences >> Atmospheric Sciences

利用 2019 年 6—9 月青海省干旱内陆区雨滴谱仪和雨量筒数据,运用物理检验法和统计方 法,分析了超高功率集束强声波干预下近地面降雨微物理特征变化。结果表明:(1)声波干预下, 累计降雨量增加,降雨量增加和减少的场次分别占研究总场次的 60.87%和 39.13%。平均粒径、液 态水含量、雷达反射率因子、雨强和降雨动能等微物理量均值明显增大,雨强和动能增幅最为明 显,分别为 36.00%和 69.20%。(2)声波干预下,平均谱大粒子端(>0.8 mm)粒子数浓度增加,且雨强 越大,粒子数浓度增加效果越明显。(3)空间分布上,作业中心周边 3 km 范围内雨强在声波干预下 显著增加。

submitted time 2021-08-01 From cooperative journals:《干旱区地理》 Hits118Downloads69 Comment 0

4. chinaXiv:202107.00039 [pdf]

Tracing the origin of SARS-CoV-2: lessons learned from the past

Qihui Wang; Hua Chen; Yi Shi; Alice C. Hughes; William J. Liu; Jingkun Jiang; George F. Gao; Yongbiao Xue; Yigang Tong
Subjects: Biology >> Virology

新冠病毒的起源仍不清楚。了解新冠病毒如何、何时以及在何处从其天然宿主传播给人类对于预防未来由冠状病毒引发的疫情至关重要。 从与病原体无休止的战斗中吸取教训,结合目前已知的关于新冠病毒起源和中间宿主的研究数据,我们提出全球多个地点都有可能是新冠病毒的起源地。

submitted time 2021-07-28 Hits9573Downloads1311 Comment 0

5. chinaXiv:202105.00045 [pdf]

用CLEAN算法对嫦娥四号低频射电频谱仪信号进行干扰抑制

刘晨迪; 周建锋; 苏彦
Subjects: Astronomy >> Astrophysical processes

嫦娥四号低频射电频谱仪放置在月球背面,其天然观测条件得天独厚。然而,嫦娥四号平台存在约10-15W/(m2*Hz)级别的强干扰,并且干扰在每道时域数据中都存在明显的差异,这大大削弱了低频射电频谱仪的天文观测灵敏度。为此,本论文从两组信号的相关性出发,提出基于CLEAN算法,借助互相关功率谱、傅立叶级数展开等工具,把低频射电频谱仪A、B、C天线的时域观测数据切分为强相关的CLEAN模型信号和部分相关的残余信号两个部分。其中CLEAN模型信号主要由平台干扰信号和可能的低频强射电爆发组成;残余信号由接收机噪声、未扣除干净的平台干扰信号和常规的低频射电信号组成。将该方法应用到实际数据中,结果表明嫦娥四号低频射电频谱仪的未积分灵敏度可以提高约8个数量级,达到10-23W/(m2*Hz)水平。在此基础上,基于对平台干扰信号中确定性成分和宽带随机成分的分别处理,再借助低频射电爆发信号和平台干扰信号在功率谱上不同的表现,以及常规低频射电天文信号受月球自转调制等信息,将来科学分析工作的重点是进一步处理CLEAN模型信号和残余信号,以期发现低频强射电天文爆发信号,乃至对全天区进行粗略的成像。

submitted time 2021-05-08 From cooperative journals:《天文研究与技术》 Hits1704Downloads364 Comment 0

6. chinaXiv:201905.00012 [pdf]

Transfer Learning for Scientific Data Chain Extraction in Small Chemical Corpus with BERT-CRF Model

Na Pang; Li Qian; Weimin Lyu; Jin-Dong Yang
Subjects: Computer Science >> Natural Language Understanding and Machine Translation

Abstract. Computational chemistry develops fast in recent years due to the rapid growth and breakthroughs in AI. Thanks for the progress in natural language processing, researchers can extract more fine-grained knowledge in publications to stimulate the development in computational chemistry. While the works and corpora in chemical entity extraction have been restricted in the biomedicine or life science field instead of the chemistry field, we build a new corpus in chemical bond field anno- tated for 7 types of entities: compound, solvent, method, bond, reaction, pKa and pKa value. This paper presents a novel BERT-CRF model to build scientific chemical data chains by extracting 7 chemical entities and relations from publications. And we propose a joint model to ex- tract the entities and relations simultaneously. Experimental results on our Chemical Special Corpus demonstrate that we achieve state-of-art and competitive NER performance.

submitted time 2019-05-12 Hits23884Downloads1592 Comment 0

7. chinaXiv:201810.00102 [pdf]

Where is the Embodiment Effect? The Hierarchical Access Priority Model

Chuanjun Liu; Jiangqun Liao; Kaiping Peng
Subjects: Psychology >> Cognitive Psychology

There are detailed theories and abundant empirical results regarding embodied cognition. However, embodiment effects are undergoing a replication crisis. Based on the hierarchical structure of embodiment tasks and the dual process property of embodiment phenomena, we propose the hierarchical access priority model (HAP). According to HAP, the generation of embodiment effects depends on the access priority of embodied variables to unconscious processes, and embodiment effects from different hierarchy levels show a contravariant relationship between effect size and stability. Theoretically, the stability of an embodiment effect is partly determined by the hierarchy of the embodied variable, and dissociation of the dual process moderates the effect size. Empirically, the hierarchical linear model analytic method should be considered for embodied research; the embodied variable could be designed as a mediating or moderating variable, and other possible masked mediating variables should be considered. HAP offers an insightful theoretical perspective for the embodiment replication crisis.

submitted time 2019-03-25 Hits11786Downloads2253 Comment 0

8. chinaXiv:201810.00184 [pdf]

Simulating hydrological responses to climate change using dynamic and statistical downscaling methods: a case study in the Kaidu River Basin, Xinjiang, China

BA Wulong; DU Pengfei; LIU Tie; BAO Anming; LUO Min; Mujtaba HASSAN; QIN Chengxin
Subjects: Geosciences >> History of Geosciences

Climate change may affect water resources by altering various processes in natural ecosystems. Dynamic and statistical downscaling methods are commonly used to assess the impacts of climate change on water resources. Objectively, both methods have their own advantages and disadvantages. In the present study, we assessed the impacts of climate change on water resources during the future periods (2020–2029 and 2040–2049) in the upper reaches of the Kaidu River Basin, Xinjiang, China, and discussed the uncertainties in the research processes by integrating dynamic and statistical downscaling methods (regional climate models (RCMs) and general circulation modes (GCMs)) and utilizing these outputs. The reference period for this study is 1990–1999. The climate change trend is represented by three bias-corrected RCMs (i.e., Hadley Centre Global Environmental Model version 3 regional climate model (HadGEM3-RA), Regional Climate Model version 4 (RegCM4), and Seoul National University Meso-scale Model version 5 (SUN-MM5)) and an ensemble of GCMs on the basis of delta change method under two future scenarios (RCP4.5 and RCP8.5). We applied the hydrological SWAT (Soil and Water Assessment Tool) model which uses the RCMs/GCMs outputs as input to analyze the impacts of climate change on the stream flow and peak flow of the upper reaches of the Kaidu River Basin. The simulation of climate factors under future scenarios indicates that both temperature and precipitation in the study area will increase in the future compared with the reference period, with the largest increase of annual mean temperature and largest percentage increase of mean annual precipitation being of 2.4°C and 38.4%, respectively. Based on the results from bias correction of climate model outputs, we conclude that the accuracy of RCM (regional climate model) simulation is much better for temperature than for precipitation. The percentage increase in precipitation simulated by the three RCMs is generally higher than that simulated by the ensemble of GCMs. As for the changes in seasonal precipitation, RCMs exhibit a large percentage increase in seasonal precipitation in the wet season, while the ensemble of GCMs shows a large percentage increase in the dry season. Most of the hydrological simulations indicate that the total stream flow will decrease in the future due to the increase of evaporation, and the maximum percentage decrease can reach up to 22.3%. The possibility of peak flow increasing in the future is expected to higher than 99%. These results indicate that less water is likely to be available in the upper reaches of the Kaidu River Basin in the future, and that the temporal distribution of flow may become more concentrated.

submitted time 2018-10-29 From cooperative journals:《Journal of Arid Land》 Hits4876Downloads1469 Comment 0

9. chinaXiv:201810.00275 [pdf]

目标预知对路径整合的影响

过继成思; 黄建平; 宛小昂
Subjects: Psychology >> Other Disciplines of Psychology

本研究采用头盔式虚拟现实与返回起点或路标的路径完成任务, 通过指导语来调控被试对于返回位置的预知, 检验目标预知对人类路径整合的影响。实验结果表明, 对于返回起点这一目标的预知可以使被试有效地忽略由于路标出现或路标数量增加而导致的干扰, 而对于返回路标这一目标的预知越多可以促使被试做出更准确的反应。这样的结果体现了目标预知作为一种非感知觉因素对于人类路径整合的影响, 也体现了人类路径整合的策略性和灵活性。

submitted time 2018-10-26 From cooperative journals:《心理学报》 Hits3448Downloads1293 Comment 0

10. chinaXiv:201809.00191 [pdf]

基于代价敏感集成极限学习机的文本分类方法

李明; 肖培伦; 张矩; 顾心盟
Subjects: Computer Science >> Natural Language Understanding and Machine Translation

加权极限学习机对不同类别的样本赋予不同的权值,在一定程度上提高了分类准确 率,但加权极限学习机只考虑了不同类别样本之间差异,忽视了样本噪声和同类样本之间的 差异。本文提出了一种基于文本类别信息熵的极限学习机集成方法,该方法以Adaboost.M1 为算法框架,通过文本的类内分布熵和类间分布熵生成文本类别信息熵,由文本类别信息熵 构造代价敏感矩阵,把代价敏感极限学习机集成到Adaboost.M1 框架中。实验结果表明,该 方法与其他类型的极限学习机相比较有更好的准确性和泛化性。

submitted time 2018-09-27 Hits2868Downloads1536 Comment 0

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