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基于Origin的土遗址防雨水侵蚀调控机理研究——以晋阳古城西城墙为例
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作者 尚瑞华 韩鹏举 +3 位作者 谷瑞芳 程驰 吴雅娟 刘伟伟 《太原理工大学学报》 CAS 北大核心 2024年第4期686-695,共10页
【目的】通过Origin软件分析,了解晋阳古城西城墙裸土土遗址与草本植物覆盖土遗址的防雨水侵蚀机理及最终效果。【方法】通过Origin软件分析原位人工模拟降雨实验数据的方法,对比植物生长状况对土遗址坡面产流、产沙效果的影响作用。【... 【目的】通过Origin软件分析,了解晋阳古城西城墙裸土土遗址与草本植物覆盖土遗址的防雨水侵蚀机理及最终效果。【方法】通过Origin软件分析原位人工模拟降雨实验数据的方法,对比植物生长状况对土遗址坡面产流、产沙效果的影响作用。【结果】产流前降雨截留量Q_(0)与新生草产流起始时间T_(0)呈负相关,且Q_(0)遵循枯草>新生草>裸土;新生草产沙系数C_(sy)、产沙强度I_(sy)与降雨强度呈显著正相关,产流、产沙效果遵循规律为裸土>枯草>新生草;裸露土遗址通过形成泥皮面层的方式,保证土体内部少受雨水浸润,适用于干旱气候区;草本植物通过强化土遗址抗冲性,减少土体表面冲刷,适用于半干旱半湿润气候区。【结论】Origin软件分析证实,草本植物提高土遗址抗冲性效果显著,草本植物覆盖土遗址现象利于山西本地土遗址保护,但当极端持续强降雨发生在9-10月间时,草本植物覆盖土遗址是否适用仍待继续研究。 展开更多
关键词 origin软件 土遗址 强降雨 侵蚀 雨水 草本
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Geochemistry and origins of hydrogen-containing natural gases in deep Songliao Basin,China:Insights from continental scientific drilling 被引量:3
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作者 Shuang-Biao Han Chao-Han Xiang +3 位作者 Xin Du Lin-Feng Xie Jie Huang Cheng-Shan Wang 《Petroleum Science》 SCIE EI CAS CSCD 2024年第2期741-751,共11页
The different reservoirs in deep Songliao Basin have non-homogeneous lithologies and include multiple layers with a high content of hydrogen gas.The gas composition and stable isotope characteristics vary significantl... The different reservoirs in deep Songliao Basin have non-homogeneous lithologies and include multiple layers with a high content of hydrogen gas.The gas composition and stable isotope characteristics vary significantly,but the origin analysis of different gas types has previously been weak.Based on the geochemical parameters of gas samples from different depths and the analysis of geological settings,this research covers the diverse origins of natural gas in different strata.The gas components are mainly methane with a small amount of C_(2+),and non-hydrocarbon gases,including nitrogen(N_(2)),hydrogen(H_(2)),carbon dioxide(CO_(2)),and helium(He).At greater depth,the carbon isotope of methane becomes heavier,and the hydrogen isotope points to a lacustrine sedimentary environment.With increasing depth,the origins of N_(2)and CO_(2)change gradually from a mixture of organic and inorganic to inorganic.The origins of hydrogen gas are complex and include organic sources,water radiolysis,water-rock(Fe^(2+)-containing minerals)reactions,and mantle-derived.The shales of Denglouku and Shahezi Formations,as source rocks,provide the premise for generation and occurrence of organic gas.Furthermore,the deep faults and fluid activities in Basement Formation control the generation and migration of mantle-derived gas.The discovery of a high content of H_(2)in study area not only reveals the organic and inorganic association of natural-gas generation,but also provides a scientific basis for the exploration of deep hydrogen-rich gas. 展开更多
关键词 Gas compositions Stable isotopes Gas origins Hydrogen gas Songliao Basin
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Origin软件在大学物理实验教学中的应用
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作者 刘念 左绪忠 +2 位作者 何恩节 秦炎福 官邦贵 《科技风》 2024年第26期124-126,共3页
Origin软件强大的数据处理及绘图能力有助于学生在大学物理实验中对数据进行分析、拟合和图像的绘制。以霍尔效应法测电螺线管轴向磁感应强度实验为例,介绍Origin软件的数据处理及拟合功能。结果表明,Origin软件的应用有效地提升了学生... Origin软件强大的数据处理及绘图能力有助于学生在大学物理实验中对数据进行分析、拟合和图像的绘制。以霍尔效应法测电螺线管轴向磁感应强度实验为例,介绍Origin软件的数据处理及拟合功能。结果表明,Origin软件的应用有效地提升了学生的绘图水平,降低了绘图误差,也为学生未来的学习和科研打下坚实的基础。 展开更多
关键词 origin 大学物理实验 霍尔效应 数据拟合
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Genetic dissection and origin of pleiotropic loci underlying multilevel fiber quality traits in upland cotton(Gossypium hirsutum L.) 被引量:1
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作者 Hongge Li Shurong Tang +7 位作者 Zhen Peng Guoyong Fu Yinhua Jia Shoujun Wei Baojun Chen Muhammad Shahid Iqbal Shoupu He Xiongming Du 《Journal of Integrative Agriculture》 SCIE CAS CSCD 2024年第10期3250-3263,共14页
Cotton fiber quality is a persistent concern that determines planting benefits and the quality of finished textile products.However,the limitations of measurement instruments have hindered the accurate evaluation of s... Cotton fiber quality is a persistent concern that determines planting benefits and the quality of finished textile products.However,the limitations of measurement instruments have hindered the accurate evaluation of some important fiber characteristics such as fiber maturity,fineness,and neps,which in turn has impeded the genetic improvement and industrial utilization of cotton fiber.Here,12 single fiber quality traits were measured using Advanced Fiber Information System(AFIS)equipment among 383 accessions of upland cotton(Gossypium hirsutum L.).In addition,eight conventional fiber quality traits were assessed by the High Volume Instrument(HVI)System.Genome-wide association study(GWAS),linkage disequilibrium(LD)block genotyping and functional identification were conducted sequentially to uncover the associated elite loci and candidate genes of fiber quality traits.As a result,the previously reported pleiotropic locus FL_D11 regulating fiber length-related traits was identified in this study.More importantly,three novel pleiotropic loci(FM_A03,FF_A05,and FN_A07)regulating fiber maturity,fineness and neps,respectively,were detected based on AFIS traits.Numerous highly promising candidate genes were screened out by integrating RNA-seq and qRT-PCR analyses,including the reported GhKRP6 for fiber length,the newly identified GhMAP8 for maturity and GhDFR for fineness.The origin and evolutionary analysis of pleiotropic loci indicated that the selection pressure on FL_D11,FM_A03 and FF_A05 increased as the breeding period approached the present and the origins of FM_A03 and FF_A05 were traced back to cotton landraces.These findings reveal the genetic basis underlying fiber quality and provide insight into the genetic improvement and textile utilization of fiber in G.hirsutum. 展开更多
关键词 upland cotton single fiber quality pleiotropic loci candidate genes locus origin
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Origin软件在声速的测量实验数据处理中的应用
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作者 杨波 邢海波 王晨辰 《大学物理实验》 2024年第4期86-88,共3页
以大学物理实验中声速的测量为例,利用了Origin软件对实验测量所得的数据进行了线性拟合,并和传统的逐差法计算结果进行了比较,两种方法所得出的声速大小几乎吻合。结果表明,在实验教学中引入Origin软件对实验数据进行处理,操作更为方... 以大学物理实验中声速的测量为例,利用了Origin软件对实验测量所得的数据进行了线性拟合,并和传统的逐差法计算结果进行了比较,两种方法所得出的声速大小几乎吻合。结果表明,在实验教学中引入Origin软件对实验数据进行处理,操作更为方便快捷,并且能够有效提高实验效率和实验准确率,避免人为因素带来的误差。 展开更多
关键词 origin软件 声速的测量 逐差法 数据处理
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Origin软件在“微生物学”实验教学中的应用——以细菌生长曲线的测定实验为例
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作者 郭佳 唐雅丽 +1 位作者 雷腊梅 许德麟 《教育教学论坛》 2024年第11期21-24,共4页
针对高校本科“微生物学”实验教学中遇到的数据处理问题,以细菌生长曲线测定的实验为例,使用Origin 2022软件进行数据导入、数据计算、图形绘制及插入误差棒等操作,完成细菌生长曲线的绘制。结果表明,利用Origin软件可以快速对实验数... 针对高校本科“微生物学”实验教学中遇到的数据处理问题,以细菌生长曲线测定的实验为例,使用Origin 2022软件进行数据导入、数据计算、图形绘制及插入误差棒等操作,完成细菌生长曲线的绘制。结果表明,利用Origin软件可以快速对实验数据进行批量处理,操作简捷并可避免人工计算的误差,对实验得到的非线性数据通过软件可以拟合出美观的图形,将实验结果可视化。在教学中通过引入Origin软件,可以在讲授具体微生物知识的同时,让本科生掌握一款专业的数据分析处理软件,有助于培养本科生的数据处理能力,提高综合科研素养,为后续实验课程和科研工作的数据处理工作打好基础。 展开更多
关键词 微生物学实验 origin 数据处理 生长曲线 实验教学改革
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Insights into the Origins of Solar-Assisted Electrochemical Water Oxidation in Allotropic Co_(5.47)N/CON Heterojunctions
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作者 Sirui Liu Qiong Gao +8 位作者 Bo Geng Lili Wu Zhikun Xu Xinzhi Ma Shijie Liu Boquan Li Mingyi Zhang Lirong Zhang Xitian Zhang 《Energy & Environmental Materials》 SCIE EI CAS CSCD 2024年第5期234-243,共10页
Solar irradiation can efficiently promote the kinetics of the oxygen evolution reaction(OER)during water splitting,where heterojunction catalysts exhibit excellent photoresponsive properties.However,insights into the ... Solar irradiation can efficiently promote the kinetics of the oxygen evolution reaction(OER)during water splitting,where heterojunction catalysts exhibit excellent photoresponsive properties.However,insights into the origins of photoassisted OER catalysis remain unclear,especially the interfaced promotion under convergent solar irradiation(CSI).Herein,novel allotropic Co_(5.47)N/CoN heterojunctions were synthesized,and corresponding OER mechanisms under CSI were comprehensively uncovered from physical and chemical aspects using the in situ Raman technique and electrochemical cyclic voltammetry method.Our results provide a unique mechanism where high-energy UV light promotes the Co^(3+/4+)conversion process in addition to the ordinary photoelectric effect excitation of the Co^(2+)material.Importantly,visible light under CSI can produce a photothermal effect for Co^(2+)excitation and Co^(3+/4+)conversion,which promotes the OER significantly more than the usual photoelectric effect.As a result,Co_(5.47)N/CoN(containing 28%CoN)obtained 317.9%OER enhancement,which provides a pathway for constructing excellent OER catalysts. 展开更多
关键词 chemical origins in situ Raman OER photothermal effect physical origins
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Identification of S-RNase genotype and analysis of its origin and evolutionary patterns in Malus plants
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作者 Zhao Liu Yuan Gao +10 位作者 Kun Wang Jianrong Feng Simiao Sun Xiang Lu Lin Wang Wen Tian Guangyi Wang Zichen Li Qingshan Li Lianwen Li Dajiang Wang 《Journal of Integrative Agriculture》 SCIE CAS CSCD 2024年第4期1205-1221,共17页
Identification of the S genotype of Malus plants will greatly promote the discovery of new genes,the cultivation and production of apple,the breeding of new varieties,and the origin and evolution of self-incompatibili... Identification of the S genotype of Malus plants will greatly promote the discovery of new genes,the cultivation and production of apple,the breeding of new varieties,and the origin and evolution of self-incompatibility in Malus plants.In this experiment,88 Malus germplasm resources,such as Aihuahong,Xishuhaitang,and Reguanzi,were used as materials.Seven gene-specific primer combinations were used in the genotype identification.PCR amplification using leaf DNA produced a single S-RNase gene fragment in all materials.The results revealed that 70 of the identified materials obtained a complete S-RNase genotype,while only one S-RNase gene was found in 18 of them.Through homology comparison and analysis,13 S-RNase genotypes were obtained:S_(1)S_(2)(Aihuahong,etc.),S_(1)S_(28)(Xixian Haitang,etc.),S_(1)S_(51)(Hebei Pingdinghaitang),S_(1)S_(3)(Xiangyangcun Daguo,etc.),S_(2)S_(3)(Zhaiyehaitang,etc.),S_(3)S_(51)(Xishan 1),S_(3)S_(28)(Huangselihaerde,etc.),S_(2)S_(28)(Honghaitang,etc.),S_(4)S_(28)(Bo 11),S_(7)S_(28)(Jiuquan Shaguo),S_(10)S_e(Dongchengguan 13),S_(10)S_(21)(Dongxiangjiao)and S_(3)S_(51)(Xiongyue Haitang).Simultaneously,the frequency of the S gene in the tested materials was analyzed.The findings revealed that different S genes had varying frequencies in Malus resources,as well as varying frequencies between intraspecific and interspecific.S_(3) had the highest frequency of 68.18%,followed by S_(1)(42.04%).In addition,the phylogenetic tree and origin evolution analysis revealed that the S gene differentiation was completed prior to the formation of various apple species,that cultivated species also evolved new S genes,and that the S_(50) gene is the oldest S allele in Malus plants.The S_(1),S_(29),and S_(33) genes in apple-cultivated species,on the other hand,may have originated in M.sieversii,M.hupehensis,and M.kansuensis,respectively.In addition to M.sieversii,M.kansuensis and M.sikkimensis may have also played a role in the origin and evolution of some Chinese apples. 展开更多
关键词 MALUS S-RNase genotype SELF-INCOMPATIBILITY origin and evolution
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Geographical origin identification of winter jujube(Ziziphus jujuba Dongzao')by using multi-element fingerprinting with chemometrics
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作者 Xiabing Kong Qiusheng Chen +8 位作者 Min Xu Yihui Liu Xiaoming Li Lingxi Han Qiang Zhang Haoliang Wan Lu Liu Xubo Zhao Jiyun Nie 《Journal of Integrative Agriculture》 SCIE CAS CSCD 2024年第5期1749-1762,共14页
Winter jujube(Ziziphus jujuba'Dongzao')is greatly appreciated by consumers for its excellent quality,but brand infringement frequently occurs in the market.Here,we first determined a total of 38 elements in 16... Winter jujube(Ziziphus jujuba'Dongzao')is greatly appreciated by consumers for its excellent quality,but brand infringement frequently occurs in the market.Here,we first determined a total of 38 elements in 167 winter jujube samples from the main winter jujube producing areas of China by inductively coupled plasma mass spectrometer(ICP-MS).As a result,16 elements(Mg,K,Mn,Cu,Zn,Mo,Ba,Be,As,Se,Cd,Sb,Ce,Er,Tl,and Pb)exhibited significant differences in samples from different producing areas.Supervised linear discriminant analysis(LDA)and orthogonal projection to latent structures discriminant analysis(OPLS-DA)showed better performance in identifying the origin of samples than unsupervised principal component analysis(PCA).LDA and OPLS-DA had a mean identification accuracy of 87.84 and 94.64%in the testing set,respectively.By using the multilayer perceptron(MLP)and C5.0,the prediction accuracy of the models could reach 96.36 and 91.06%,respectively.Based on the above four chemometric methods,Cd,Tl,Mo and Se were selected as the main variables and principal markers for the origin identification of winter jujube.Overall,this study demonstrates that it is practical and precise to identify the origin of winter jujube through multi-element fingerprint analysis with chemometrics,and may also provide reference for establishing the origin traceability system of other fruits. 展开更多
关键词 winter jujube multi-element fingerprint analysis CHEMOMETRICS origin traceability
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Management of retroperitoneal high-grade serous carcinoma of unknown origin:A case report
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作者 Wen-Lin Hsieh Dah-Ching Ding 《World Journal of Clinical Cases》 SCIE 2024年第6期1190-1195,共6页
BACKGROUND Retroperitoneal high-grade serous carcinoma(HGSC)of unknown origin is a sporadic tumor that can originate from ovarian cancer.Herein,we report the case of a woman with retroperitoneal HGSC of unknown origin... BACKGROUND Retroperitoneal high-grade serous carcinoma(HGSC)of unknown origin is a sporadic tumor that can originate from ovarian cancer.Herein,we report the case of a woman with retroperitoneal HGSC of unknown origin and describe how she was diagnosed and treated.CASE SUMMARY A 71-year-old female presented with the tumor marker CA125 elevated to 1041.9 U/mL upon a regular health examination.Computed tomography revealed retroperitoneal lymph node enlargement.Subsequently,positron emission tomography scanning revealed lesions with increased F-18 fluorodeoxyglucose uptake at the nodes.As a result,she underwent laparoscopic lymph node resection,and pathology revealed metastatic adenocarcinoma with CK7(+),PAX8(+),WT1(+),PR(-),and p53 mutational loss of expression,indicating that the origin may be from the adnexa.The patient was admitted to our ward and underwent laparoscopic staging;however,the pathological results were negative.Under the suspicion of retroperitoneal HGSC of unknown origin,chemotherapy and targeted therapy were initiated.Tumor marker levels decreased after treatment.CONCLUSION We present a case of HGSC of unknown origin managed using retroperitoneal lymphadenectomy,staging surgery,chemotherapy,and targeted therapy. 展开更多
关键词 High-grade serous carcinoma RETROPERITONEUM origin CHEMOTHERAPY Lymph node Case report
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Origin of the Dashuigou independent tellurium deposit at Qinghai–Xizang Plateau: constraints from the light stable isotopes C, O, and H
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作者 Jianzhao Yin Yuhong Chao +2 位作者 Haoyu Yin Hongyun Shi Shoupu Xiang 《Acta Geochimica》 EI CAS CSCD 2024年第2期385-398,共14页
By studying the light isotopic compositions of carbon,oxygen,and hydrogen,combined with previous research results on the ore-forming source of the deposit,the authors try to uncover its metallogenic origin.The δ^(18)... By studying the light isotopic compositions of carbon,oxygen,and hydrogen,combined with previous research results on the ore-forming source of the deposit,the authors try to uncover its metallogenic origin.The δ^(18)O and δ^(13)C isotope signatures of dolomite samples vary between 10.2 and 13.0‰,and between−7.2 and−5.2‰,respectively,implying that the carbon derives from the upper mantle.δD and δ^(18) O of quartz,biotite,and muscovite from diff erent ore veins of the deposit vary between−82 and−59‰,and between 11.6 and 12.4‰,respectively,implying that the metallogenic solutions are mainly magmatic.According to the relevant research results of many isotope geologists,the fractionation degree of hydrogen isotopes increases as the depth to the Earth’s core increases,and the more diff erentiated the hydrogen isotopes are,the lower their values will be.In other words,mantle-derived solutions can have extremely low hydrogen isotope values.This means that the δD‰ value−134 of the pyrrhotite sample numbered SD-34 in this article may indicate mantle-derived oreforming fl uid of the deposit.The formation of the Dashuigou tellurium deposit occurred between 91.71 and 80.19 Ma. 展开更多
关键词 Carbon oxygen and hydrogen isotopes origin Independent tellurium deposit The Qinghai–Xizang Plateau
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Unroofing Technique for Anomalous Origin of the Left Coronary Artery from the Right Sinus of Valsalva: Report of a Case
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作者 Keisuke Morimoto Futoshi Kobayashi +2 位作者 Hiromu Horie Yuki Sakaguchi Einosuke Mizuta 《World Journal of Cardiovascular Surgery》 2024年第6期69-77,共9页
Anomalous origin of the left coronary artery (AOLCA) from the right sinus of Valsalva constitutes a rare congenital coronary artery anomaly. Patients with an anomalous left main coronary artery face a significantly hi... Anomalous origin of the left coronary artery (AOLCA) from the right sinus of Valsalva constitutes a rare congenital coronary artery anomaly. Patients with an anomalous left main coronary artery face a significantly higher risk of sudden cardiac death compared to those with an anomalous right coronary artery. The anomalous coronary artery traversing between the ascending aorta and the pulmonary artery markedly heightens the risk of myocardial ischemia, arrhythmia, and sudden death. Symptomatic patients often exhibit a longer intramural course of the coronary artery, which may necessitate earlier intervention or influence the choice of surgical repair method. Surgical intervention is advocated for patients with this anomaly, even in the absence of symptoms. For anomalous aortic origin of a coronary artery from the opposite sinus of Valsalva with an intramural course, coronary unroofing is the preferred revascularization procedure. This report presents a case of AOLCA originating from the right sinus of Valsalva, treated surgically using the unroofing technique for the aortic intramural segment of the anomalous coronary artery traversing between the great vessels. The unroofing technique is recommended for treating AOLCA with an extensive intramural course that does not involve the commissure. 展开更多
关键词 Unroofing Technique Anomaly of Coronary Artery Anomalous origin of Left Coronary Artery
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Millet Origin Identification Model Based on Near-infrared Spectroscopy
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作者 Penghe LYU Dongfeng YANG 《Agricultural Biotechnology》 2024年第3期31-33,共3页
[Objectives]This study was conducted to clarify the difference of millet from different producing areas in near-infrared spectroscopy(NIRS)modeling.[Methods]Millet samples from six different regions were collected for... [Objectives]This study was conducted to clarify the difference of millet from different producing areas in near-infrared spectroscopy(NIRS)modeling.[Methods]Millet samples from six different regions were collected for NIRS analysis,and an origin identification model based on BP neural network was established.The competitive adaptive reweighted sampling(CARS)algorithm was used to extract characteristic wavelength variables,and a CARS-BP model was established on this basis.Finally,the CARS-BP model was compared with support vector machine(SVM),partial least squares discriminant analysis(PLS)and KNN models.[Results]The characteristic wavelengths were extracted by CARS,and the number of variables was reduced from 1845 to 130.The discrimination accuracy of the CARS-BP model for the samples from six producing areas reached 98.1%,which was better than SVM,PSL and KNN models.[Conclusions]NIRS can quickly and accurately identify the origin of millet,providing a new method and way for the origin identification and quality evaluation of millet. 展开更多
关键词 MILLET Identification of origin CARS-BP model NIR
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Gibbon vocal communication provides insights into the origin and evolution of human music and language
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作者 Zi-Di Wang Hai-Gang Ma Peng-Fei Fan 《Zoological Research(Diversity and Conservation)》 2024年第2期130-132,共3页
Humans across cultures convey feelings and thoughts through music.Despite its ubiquity,the origins and evolution of music remain enigmatic.Archaeological evidence has traced the history of music back at least 40000 ye... Humans across cultures convey feelings and thoughts through music.Despite its ubiquity,the origins and evolution of music remain enigmatic.Archaeological evidence has traced the history of music back at least 40000 years ago based on prehistoric bone flutes(Fitch,2006).Comparative studies have also explored earlier histories by identifying common musical features between animals and humans(Fitch,2006).For example,songbirds exhibit categorical rhythms similar to human music(Roeske et al.,2020),and humans can recognize emotional arousal in signals across all classes of terrestrial vertebrates(Filippi et al.,2017).These findings,while surprising,align with the longstanding human perception of animal signals as music(Gray et al.,2001).The universality of music and its features intensifies the fundamental question posed by Darwin(1871):how has a behavior that is energetically costly and seemingly non-adaptive evolved to become so widespread?This question can be further divided into two sub-questions(Savage et al.,2021):(1)how do musical features contribute to the production or expressive power of music(i.e.,mechanisms),and(2)how does music benefit performers in terms of survival,reproductions,or other aspects(i.e.,functions). 展开更多
关键词 COMMUNICATION origin evolution
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Research on the origin and evolution of technical management regulations for railway
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作者 Lei Tian Yuming Sun Yonggang Jia 《Railway Sciences》 2024年第6期779-787,共9页
Purpose–To facilitate technical managers and field workers to master and understand the provisions of Technical Management Regulations for Railway more accurately,so as to better serve the comprehensive revision of t... Purpose–To facilitate technical managers and field workers to master and understand the provisions of Technical Management Regulations for Railway more accurately,so as to better serve the comprehensive revision of the Regulations,this paper carries out the research on the traceability and evolution of the provisions of the Regulations.Design/methodology/approach–This paper studies and analyzes the evolution of the 11th edition of the Regulations by analyzing the relevance of clauses and summarizes the historical background of the development of calendar editions of the Regulations.The basic research on the traceability and evolution of the Regulations is carried out from four aspects:the continuity of the development of the Regulations,the authority of contents,the relevance of clauses and the richness of historical materials.Findings–From the first edition of the Regulations issued by the former Ministry of Railways in 1950 to the 11th edition,there have been ten comprehensive revisions.There is a strong correlation and continuity between the calendar editions of the Regulations in terms of chapter structure and clauses.Studying the context of the terms of the Regulations is an important way to understand and master the current clauses of the Regulations.Originality/value–Through the research on the traceability and evolution of the clauses of the Regulations,one is to explore the context of the development of railway technical equipment in China,the other is to clarify the historical background when the provisions were formulated and the third is to trace the development and evolution of the provisions.The revision of the Regulations is based on an accurate grasp of the context of the provisions,which can effectively judge the possible security risks caused by the revision of the provisions and avoid the possible risks in field implementation from the source. 展开更多
关键词 Technical management regulations for railway origin and evolution REVISION Technical regulation Organization of train operation
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最小二乘法和Origin软件在牛顿第二运动定律验证实验的数据处理中的应用
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作者 胡丹 尚宏伟 +1 位作者 李亚琴 杨癸 《佳木斯大学学报(自然科学版)》 CAS 2024年第1期173-176,共4页
用最小二乘法和Origin软件分别对牛顿第二运动定律验证实验的实验数据进行处理。计算结果表明,Origin软件在处理实验数据方面具有快速、灵活、便捷等优势,避免了因人为因素所造成的误差,因而在实验数据处理中具有广泛的应用前景。
关键词 最小二乘法 origin软件 牛顿第二运动定律
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Scientists Clarify the Origins of Lunar Metallic Iron
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《Bulletin of the Chinese Academy of Sciences》 2024年第2期97-98,共2页
Metallic iron nanoparticles(npFe0)are widespread on the Moon,and their accumulation changes the optical spectra of the lunar surface over time.How the surface color changes largely depends on the size of npFe0:smaller... Metallic iron nanoparticles(npFe0)are widespread on the Moon,and their accumulation changes the optical spectra of the lunar surface over time.How the surface color changes largely depends on the size of npFe0:smaller npFe0 reddens the reflectance spectra,while larger npFe0 causes darkening.The resultant color variations greatly complicate remote sensing studies,posing long-term puzzles to astronomers. 展开更多
关键词 origin SURFACE reflectance
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Optimization study of station track utilization in high-speed railroad based on constraints of control in random origin and process
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作者 Yajing Zheng Dekun Zhang 《Railway Sciences》 2024年第3期332-343,共12页
Purpose-The purpose of this paper is to eliminate the fluctuations in train arrival and departure times caused by skewed distributions in interval operation times.These fluctuations arise from random origin and proces... Purpose-The purpose of this paper is to eliminate the fluctuations in train arrival and departure times caused by skewed distributions in interval operation times.These fluctuations arise from random origin and process factors during interval operations and can accumulate over multiple intervals.The aim is to enhance the robustness of high-speed rail station arrival and departure track utilization schemes.Design/methodologylapproach-To achieve this objective,the paper simulates actual train operations,incorporating the fluctuations in interval operation times into the utilization of arrival and departure tracks at the station.The Monte Carlo simulation method is adopted to solve this problem.This approach transforms a nonlinear model,which includes constraints from probability distribution functions and is difficult to solve directly,into a linear programming model that is easier to handle.The method then linearly weights two objectives to optimize the solution.Findings-Through the application of Monte Carlo simulation,the study successfully converts the complex nonlinear model with probability distribution function constraints into a manageable linear programming model.By continuously adjusting the weighting coefficients of the linear objectives,the method is able to optimize the Pareto solution.Notably,this approach does not require extensive scene data to obtain a satisfactory Pareto solution set.Originality/value-The paper contributes to the field by introducing a novel method for optimizing high-speed rail station arrival and departure track utilization in the presence of fluctuations in interval operation times.The use of Monte Carlo simulation to transform the problem into a tractable linear programming model represents a significant advancement.Furthermore,the method's ability to produce satisfactory Pareto solutions without relying on extensive data sets adds to its practical value and applicability in real-world scenarios. 展开更多
关键词 Control in random origin Control in random process High-speed railroad station Arrival and departure track utilization Optimization Paper type Research paper
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汲取“伟人”智慧,创新“素养”提升--利用Tracker和 Origin软件探究自由落体运动
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作者 王军峰 李晓静 《数理天地(高中版)》 2024年第6期110-112,共3页
伽利略对于自由落体运动的研究囊括了数学推理、实验验证和思想外推.本文汲取“伟人”--伽利略的自由落体运动研究的思想,并以现代技术手段--Tracker软件获取数据和Origin软件处理数据为抓手,创新自由落体运动的探究过程,促进学生科学... 伽利略对于自由落体运动的研究囊括了数学推理、实验验证和思想外推.本文汲取“伟人”--伽利略的自由落体运动研究的思想,并以现代技术手段--Tracker软件获取数据和Origin软件处理数据为抓手,创新自由落体运动的探究过程,促进学生科学探究和科学思维等学科核心素养的提升,以期专家和同行指正. 展开更多
关键词 自由落体运动 Tracker软件 origin软件
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基于Origin的波形钢腹板屈曲试验数据处理研究
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作者 刘丹 高京华 李彦辰 《中文科技期刊数据库(全文版)工程技术》 2024年第7期0156-0160,共5页
波形钢腹板被广泛应用于各种工程结构中,由于其独特的几何形状,在外载荷作用下易发生剪切屈曲破坏。本文首先介绍了试验概况和试验数据情况,研究利用Origin软件进行波形钢腹板剪切屈曲试验数据的归纳和整理,通过绘制折线图和柱状图对波... 波形钢腹板被广泛应用于各种工程结构中,由于其独特的几何形状,在外载荷作用下易发生剪切屈曲破坏。本文首先介绍了试验概况和试验数据情况,研究利用Origin软件进行波形钢腹板剪切屈曲试验数据的归纳和整理,通过绘制折线图和柱状图对波形钢腹板的屈曲特性进行了定性分析。结果表明,Origin软件可有效辅助波形钢腹板屈曲试验数据的处理,提高数据解读的准确性和效率。波形钢腹板工字梁屈曲试验表明,剪应力沿高度方向虽并非完全均匀分布,但相差不大,现有规范“剪应力沿波形钢腹板高度方向均匀分布”的假定是合理的,“剪力由波形钢腹板承担”的假定,上下翼缘板是否参与抗剪还有待进一步验证。 展开更多
关键词 波形钢腹板工字梁 屈曲试验 origin软件
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