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Soil shear properties as infl uenced by straw content:An evaluation of field-collected and laboratory-remolded soils

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Journal of Integrative Agriculture 2016年第12期15卷 2848-2854页

作者： fang hui-min ZHANG Qing-yi JI Chang-ying GUO Jun College of Engineering Nanjing Agricultural University

Following a rice or wheat harvest, a large amount of crop residue （straw） is retained in fields. The straw is often incorporated into the soil in order to increase the soil organic carbon storage and to reduce soil erosion. However, it has become apparent that the incorporated straw can significantly alter soil shear properties, which can dramatically affect energy inputs for tilling and other soil management practices. In this study, laboratory-remolded wheat straw-soil samples were compared with field-collected straw-soil samples; we found high correlations for the cohesion （R2=0.9084） and internal friction angle （R2=0.9548） properties of the samples. Shear tests on rice and wheat straw with different moisture content levels clearly demonstrated the relatively higher shear strength of wheat straw compared to rice straw. The cohesion of remolded rice and wheat straw-soil samples exhibited an increasing linear trend with an increase in densities, whereas the internal friction angle data for these samples exhibited a quadratic trend. Overlapping the cohesion curves revealed that the wheat straw-soil and rice straw-soil samples had the same cohesion at a straw density of 0.63%. Similar results were obtained when the internal fraction angle curves overlapped; the resultant point of intersection was observed at a straw density of 0.46%. As a whole, the remolded sample methodology was found suitable to simulate the shear properties of soils sampled directly from fields.

关键词： direct shear test wheat straw rice straw cohesion internal friction angle

Origin of Negative Imaginary Part of Effective Permittivity of Passive Materials

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Chinese Physics Letters 2017年第9期34卷 105-108页

作者： Kai-Lun Zhang Zhi-Ling Hou Ling-Bao Kong hui-min fang Ke-Tao Zhan School of Science ＆ Beijing Laboratory of Enyironmentally Harmful Chemicals Assessment Beijing University of Chemical Technology Beijing 100029 Key of Science Beijing Technology and Business University Beijing 100048

The anti-resonant phenomenon of effective electromagnetic parameters of metamaterials has aroused controversy due to negative imaginary permittivity or permeability. It is experimentally found that the negative imaginary permittivity can occur for the natural passive materials near the Fabry Perot resonances. We reveal the nature of negative imaginary permittivity, which is correlated with the magnetoelectric coupling. The anti-resonance of permittivity is a non-inherent feature for passive materials, while it can be inherent for devices or metamaterials. Our finding validates that the negative imaginary part of effective permittivity does not contradict the second law of thermodynamics for metamaterials owing to the magnetoelectric coupling.

关键词： Origin of Negative Imaginary Part of Effective Permittivity of Passive Materials FPR

Machine learning-based grayscale analyses for lithofacies identification of the Shahejie formation, Bohai Bay Basin, China

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Petroleum Science 2025年第1期22卷 42-54页

作者： Yu-Fan Wang Shang Xu fang Hao hui-min Liu Qin-Hong Hu Ke-Lai Xi Dong Yang National Key Laboratory of Deep Oil and Gas China University of Petroleum (East China) Shengli Oilfield Branch Company SINOPEC

It is of great significance to accurately and rapidly identify shale lithofacies in relation to the evaluation and prediction of sweet spots for shale oil and gas reservoirs. To address the problem of low resolution in logging curves, this study establishes a grayscale-phase model based on high-resolution grayscale curves using clustering analysis algorithms for shale lithofacies identification, working with the Shahejie Formation, Bohai Bay Basin, China. The grayscale phase is defined as the sum of absolute grayscale and relative amplitude as well as their features. The absolute grayscale is the absolute magnitude of the gray values and is utilized for evaluating the material composition(mineral composition + total organic carbon) of shale, while the relative amplitude is the difference between adjacent gray values and is used to identify the shale structure type. The research results show that the grayscale phase model can identify shale lithofacies well, and the accuracy and applicability of this model were verified by the fitting relationship between absolute grayscale and shale mineral composition, as well as corresponding relationships between relative amplitudes and laminae development in shales. Four lithofacies are identified in the target layer of the study area: massive mixed shale, laminated mixed shale, massive calcareous shale and laminated calcareous shale. This method can not only effectively characterize the material composition of shale, but also numerically characterize the development degree of shale laminae, and solve the problem that difficult to identify millimeter-scale laminae based on logging curves, which can provide technical support for shale lithofacies identification, sweet spot evaluation and prediction of complex continental lacustrine basins.

关键词： Shale Machine learning Absolute grayscale Relative amplitude Grayscale phase model Lithofacies identification

Study on the off situ reconstruction of the core neutron field based on dual-task hybrid network architecture

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Nuclear Science and Techniques 2025年第1期36卷 175-191页

作者： Pei Cao hui Ding Cheng-Long Cao Zi-hui Yang Guo-min Sun School of Artificial Intelligence and Big Data Hefei UniversityHefei 230001China College of Electronic Engineering National University of Defense TechnologyHefei 230001China Institute of Nuclear Energy Safety Technology HFIPSChinese Academy of SciencesHefei 230027China

The off situ accurate reconstruction of the core neutron field is an important step in realizing real-time reactor *** existing off situ reconstruction method of the neutron field is only applicable to cases wherein a single region changes at a specified location of the ***,when the neutron field changes are complex,the accurate identification of the individual changed regions becomes challenging,which seriously affects the accuracy and stability of the neutron field ***,this study proposed a dual-task hybrid network architecture(DTHNet)for off situ reconstruction of the core neutron field,which trained the outermost assembly reconstruction task and the core reconstruction task jointly such that the former could assist the latter in the reconstruction of the core neutron field under core complex ***,to exploit the characteristics of the ex-core detection signals,this study designed a global-local feature upsampling module that efficiently distributed the ex-core detection signals to each reconstruction unit to improve the accuracy and stability of *** experiments were performed on the simulation datasets of the CLEAR-I reactor to verify the accuracy and stability of the proposed *** results showed that when the location uncertainty of a single region did not exceed nine and the number of multiple changed regions did not exceed ***,the reconstructed ARD was within 2%,RD_(max)was maintained within 17.5%,and the number of RD≥10%was maintained within ***,when the noise interference of the ex-core detection signals was within±2%,although the average number of RD≥10%increased to 16,the average ARD was still within in 2%,and the average RD_(max)was within 22%.Collectively,these results show that,theoretically,the DTHNet can accurately and stably reconstruct most of the neutron field under certain complex core changes.

关键词： Real-time reactor monitoring Core neutron field reconstruction Dual-task hybrid network architecture Global-local feature upsampling module

平台品牌赋能情境下考虑信息不对称的供应链渠道冲突

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控制与决策 2021年第9期36卷 2123-2132页

作者：肖迪方慧敏鲁其辉殷西乐浙江工商大学工商管理学院杭州310018 浙江工商大学现代商贸研究中心杭州310018

随着平台型电商企业对供应链合作伙伴的赋能行为迅速增加,对供应链成员的运营决策及收益产生了举足轻重的影响.在平台型电商企业进行品牌赋能的情境下,研究由一个平台型电商企业、一个零售商和一个其他渠道供应商构成的供应链中,如何设... 详细信息

随着平台型电商企业对供应链合作伙伴的赋能行为迅速增加,对供应链成员的运营决策及收益产生了举足轻重的影响.在平台型电商企业进行品牌赋能的情境下,研究由一个平台型电商企业、一个零售商和一个其他渠道供应商构成的供应链中,如何设计合适的激励机制以缓解供应链成员之间的垂直渠道冲突,并在信息不对称的条件下,剖析作为核心企业的平台型电商企业如何运用机制设计的方法来识别零售商从其他渠道订购产品的质量水平.研究表明,平台型电商企业可以通过设计包括混合策略与分离策略在内的激励机制来提升零售商从平台型电商企业订购产品的数量和比例.若零售商从产品质量较高的其他渠道供应商订购产品的概率较高时,则平台型电商企业采用分离策略更有助于提升零售商的总订购量,反之则应采用混合策略.平台型电商企业在分离策略下获得的期望利润要大于混合策略,并且均大于不向零售商提供激励机制的情形.

关键词：电子商务品牌赋能供应链不对称信息渠道冲突激励机制

New Insights on Gamma-Ray Burst Radiation Mechanisms from Multiwavelength Observations

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Research in Astronomy and Astrophysics 2025年第2期25卷 3-12页

作者： Yu-Hua Yao fang-Sheng min Shi Chen Yi-Qing Guo College of Physics Chongqing University Key Laboratory of Particle Astrophysics Institute of High Energy Physics Chinese Academy of Sciences Wisconsin Ice Cube Particle Astrophysics Center University of Wisconsin–Madison University of Chinese Academy of Sciences School of Physics and Astronomy Yunnan University Tianfu Cosmic Ray Research Center

The study of high-energy gamma-ray emission from gamma-ray bursts(GRBs) involves complex synchrotron radiation and synchrotron self-Compton(SSC) scattering mechanisms with multiple parameters exhibiting a wide distribution. Recent advancements in GRB research, particularly the observation of very high energy(VHE,>100 Ge V) radiation, have ushered in a new era of multiwavelength exploration, offering fresh perspectives and limitations for understanding GRB radiation mechanisms. This study aimed to leverage VHE observations to refine constraints on synchrotron + SSC radiation from electrons accelerated by forward shocks. By analyzing two external environments—the uniform interstellar medium and stratified stellar wind medium, we conducted spectral and variability fitting for five specific bursts(GRB 180720B, GRB 190114C, GRB 190829A, GRB 201216C, and GRB 221009A) to identify the optimal parameters characterizing these events. A comparative analysis of model parameter distributions with and without VHE radiation observations reveals that the magnetic energy equipartition factor εBis more concentrated with VHE emissions. This suggests that VHE emissions may offer greater constraints on this microphysical parameter. Additionally, we found that the energy budget between VHE and ke V–Me V γ-ray emissions under the SSC radiation exhibits an almost linear relationship, which may serve as a tool to differentiate radiation mechanisms. We anticipate future statistical analyses of additional VHE bursts to validate our findings.

关键词： (transients:) gamma-ray bursts gamma-rays: ISM radiation mechanisms: non-thermal

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生物入侵及入侵进化生物学

安徽大学学报（自然科学版） 2006年第2期30卷 86-90页

作者：方惠敏安徽大学现代实验技术中心安徽合肥230039

分析生物入侵与全球变化的相互作用关系以及生物入侵的负面影响,以期为入侵外来物种的预防、控制和管理提供理论依据.同时分析了生物入侵的进化问题,尽管生物入侵已经导致全球生物多样性的严重丧失和生态系统的严重破坏,但同时也为物种... 详细信息

分析生物入侵与全球变化的相互作用关系以及生物入侵的负面影响,以期为入侵外来物种的预防、控制和管理提供理论依据.同时分析了生物入侵的进化问题,尽管生物入侵已经导致全球生物多样性的严重丧失和生态系统的严重破坏,但同时也为物种进化提供了新的源泉.生物入侵过程中出现的进化可以是特定生物类群某些形态或习性上的细微调整,也可是生物学上的巨大改变,甚至是新物种的形成,对外来入侵生物的研究,有待于向不同层次和更高水平、多学科交叉的实验与理论研究的方向发展.

关键词：生物入侵全球变化外来种土著种进化

Galileo multi-day precise orbit determination using L-band and SLR data

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Geodesy and Geodynamics 2025年第1期16卷 99-110页

作者： Tianhe Xu Honglei Yang Song Li Zhenlong fang Wenfeng Nie min Li Baoguo Yu Shandong Key Laboratory of Optical Astronomy and Solar-Terrestrial Environment Institute of Space Sciences Shandong University Navigation Laboratory of the 54th Research Institute of China Electronics Technology Group Corporation

The continuously available satellites of European Galileo currently reach more than 25. To explore the rationality and reliability of the L-band and satellite laser ranging(SLR) data processing strategies, we design the Galileo L-band, the SLR-only, and the combined L-band/SLR dynamic precise orbit determination(POD) strategies by using the normal equations(NEQs) stacking, and investigate their continuity and stability by employing the Galileo L-band data and SLR observations for the time span of the whole year of 2023, based on the Bei Dou/GNSS analysis center platform of Shandong University by using the modified Bernese GNSS Software Version 5.4. The orbital consistency of the L-band 1-day solution is the best with the Three-dimensional Root-Mean-Square(3D-RMS) values of 3.6 cm compared with the Center for Orbit Determination in Europe Multi-GNSS Experiment(COM) orbits, the corresponding values is 1.4 cm, 2.5 cm, and 2.3 cm in Radial, the Tangential, and the Normal(RTN) direction, respectively. While the SLR-only 9-day arc length is optimal with the RTN values of 5.3 cm, 30 cm, and 38.2 cm,as well as the 3D-RMS values of 48.9 cm. Encouragingly, the difference of the orbital accuracy between the combined L-band/SLR multi-day solution and the COM orbits is reduced by 0.5 cm and 0.9 cm, 0.6 cm and 1.2 cm in T-, and N-direction for the 3-and 5-day solution respectively. The corresponding values improve 0.7 cm and 0.9 cm, 1.4 cm and 1.8 cm for the 3-and 5-day orbital overlaps difference between the combined L-band/SLR and the L-band solution. Take the E09 satellite as a case study, the SLR-only orbital accuracy is regularly optimized as the multi-day arc lengthens and with the sites ***, the SLR residuals of its three types of orbits further demonstrate the positive contribution of SLR to the combination of the GNSS and SLR techniques.

关键词： Galileo POD SLR L-band NEQs stacking

The relationship between CDK13 and TBAD patients undergoing TEVAR

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South China Journal of Cardiology 2019年第2期20卷 121-124,130页

作者： LIU hui-Ling GUAN Jin-zhen FENG Yu-liang HUANG Wei CAI Liu-yang JIANG Lei LUO Jian-fang fang hui-min Department of Cardiology Guangdong Cardiovascular InstituteGuangdong Provincial Key Laboratory of Coronary DiseaseGuangdong Provincial People's HospitalGuangdong Academy of Medical SciencesGuangzhou 510000 Shenzhen 1Dao Medical Laboratory Shenzhen 518000 Shenzhen Wanzhong Gene Translation Medical Research Institute Shenzhen 518000China The Chinese University of Hong Kong Hong Kong 999077China

Background Type B aortic dissections(TBAD)are catastrophic conditions with high complication and mortality rates. This study aimed to investigate the prognostic significance of CDK13 expression in patients with type B aortic dissection(TBAD)undergoing thoracic endovascular aortic repair(TEVAR). Methods Totally 56 patients with TBAD undertaken TEVAR were included in this study,CDK13 expression was detected in blood samples which were collected from vein before angiography. We reviewed hospital readmission records and outpatient clinic interviews for possible events. The primary endpoint was long-term all-cause mortality. The secondary endpoints were in-hospital major adverse clinical events(MACEs). Results A total of 56 patients(mean age 61.2±12.4 years)were included in the study. We divided the patients into 2 risk levels(28 patients for each level)according to the median of CDK13 expression. The in-hospital mortality(3.6% vs. 14.2%,P<0.05)and MACEs(10.7% vs. 39.3%,P<0.05)were significant higher in patients with high CDK13 level(≥ median).Conclusions The expression level of CDK13 could be considered as a relatively simple tool for pre-TEVAR risk stratification.[S Chin J Cardiol 2019;20(2):121-124]

关键词： CDK13 type B aortic dissections thoracic endovascular aortic repair