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Analysis on Combining Ability and Genetic Parameters of Main Agronomic Characters of 22 Maize Inbred Lines
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作者 张亚勤 邱正高 +5 位作者 杨华 祁志云 汤玲 李淑君 张丕辉 袁亮 《Agricultural Science & Technology》 CAS 2015年第9期1907-1911,1915,共6页
The general combining ability(GCA), special combining ability(SCA) and genetic parameter of ten characters of 22 maize inbred lines including plant height and ear height were analyzed using 10×12 through inco... The general combining ability(GCA), special combining ability(SCA) and genetic parameter of ten characters of 22 maize inbred lines including plant height and ear height were analyzed using 10×12 through incomplete diallel cross(NC Ⅱ).The results showed that:(1) Among the 22 maize inbred lines, the yield GCAs of11 HN 097, 11 HN 099, 11 HN 105 and 11 HN 110 were high, which were elite inbred lines to collocate hybridized combinations with strong heterosis. The yield of11 HN110 × 11 HN097, 11 HN110 × 11 HN105, 11 HN112 × 11 HN 097 and 11 HN 106 × 11 HN 104 were in the first four place. The yielding abilities, adaptabilities and yielding stabilities of the four combinations can be further identified by experiment. The heredities of the ten characters were mainly controlled by additive gene effect whereas the influence of non-addictive gene effect was small. The narrow heritabilities of plant height, ear height, ear rows, ear length, kernels per row,100-grain weight and seed-producing percentage were more than 50%. The variances were mainly caused by heredity and early-generation selection should be conducted. The narrow heritabilities of ear diameter, bare tip length and yield was low, which should not be selected in early-generation. 展开更多
关键词 MAIZE Inbred line Combining ability Genetic parameter
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Dependence of Amorphous Formation Ability on Intrinsic Parameters in Dy-Gd-Co-Al Alloys
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作者 Lin Luo Rui Tian Xueshan Xiao 《Journal of Materials Science & Technology》 SCIE EI CAS CSCD 2009年第5期665-668,共4页
A series of Dy(Gd)-based bulk amorphous alloy rods were prepared by water-cooled copper mold method. Thermal stability and structure of Dy-Gd-Co-Al alloys were investigated by differential scanning calorimetry and X... A series of Dy(Gd)-based bulk amorphous alloy rods were prepared by water-cooled copper mold method. Thermal stability and structure of Dy-Gd-Co-Al alloys were investigated by differential scanning calorimetry and X-ray diffraction, respectively. The results show that the Dy-Gd-Co-Al alloys have good glass-formation ability, and the Dy31Gd25Co20Al24 alloy can be readily cast into full glassy rods up to 5 mm in diameter. The glass-forming ability of multicomponent alloys was greatly dependent on their chemical interaction and the equivalent bond parameters among atoms such as equivalent electronegativity difference, equivalent atomic size parameter. The Dy (Gd)-based bulk amorphous alloys could be expected as potential functional materials. 展开更多
关键词 Dy(Gd)-based Glass forming ability Intrinsic parameters
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Combining Ability and Correlation of Ear Characteristics of Twenty Maize Inbred Lines 被引量:2
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作者 李淑君 董昕 +3 位作者 付忠军 祁志云 张丕辉 周汝平 《Agricultural Science & Technology》 CAS 2017年第9期1601-1606,共6页
The combining ability and correlation of eight ear characteristics in 99 maize hybrids generated by crossing nine female parents with 11 male parents were analyzed by incomplete diallel cross (NC II ) design. The re... The combining ability and correlation of eight ear characteristics in 99 maize hybrids generated by crossing nine female parents with 11 male parents were analyzed by incomplete diallel cross (NC II ) design. The results showed that the line F6 had the highest general combining ability (GCA) for yield, followed by F7, M3, M4 and M8. All of the five lines have great potential in maize breeding. The cross combination M3xF10 had the highest specific combining ability (SCA) for yield, showing strong heterosis. Heritability analysis of ear characteristics showed that GCA variance was higher than SCA variance in ear diameter, number of rows per ear and seed rate, and they were mainly controlled by the additive gene effect, indicating that that the selections for these traits are effective at early generations. The other three traits had lower SCA, for which the selections should be carried out at late generations. The correlation analysis revealed that ear length, number of grains per row, ear diameter, number of rows per ear, 100-seed weight and seed rate had extremely significant positive correlations with grain yield per plant. Among them, number of grains per row had the most significant effect on yield per plant. Barren tip length had a significant negative correlation with grain yield per plant. Therefore, we concluded that the combinations with more grains per row and shorter barren tip should be selected to achieve high yield of maize. 展开更多
关键词 MAIZE Inbred line Combining ability Ear characteristics Genetic parameters
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Evaluation of the mold-filling ability of alloy melt in squeeze casting 被引量:8
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作者 Haiying Zhang Shuming Xing +2 位作者 Qinghua Zhang Jianbo Tan Wen Liu 《Journal of University of Science and Technology Beijing》 CSCD 2006年第1期60-66,共7页
The mold-filling ability of alloy mclt in squceze casting process was evaluated by means of the maximum length of Archimedes spiral line. A theoretical evaluating model to predict the maximum filling length was built ... The mold-filling ability of alloy mclt in squceze casting process was evaluated by means of the maximum length of Archimedes spiral line. A theoretical evaluating model to predict the maximum filling length was built based on the flowing theory of the incompressible viscous fluid. It was proved by experiments and calculations that the mold-tilling pressure and velocity are prominent influencing factors on the mold-filling ability of alloy melt. The mold-filling ability increases with the increase of the mold-filling pressure and the decrease of the proper mold-filling velocity. Moreover, the pouring temperature relatively has less effect on the mold-filling ability under the experimental conditions. The maximum deviation of theoretical calculating values with experimental results is less than 15%. The model can quantitatively estimate the effect of every factor on the mold-filling ability. 展开更多
关键词 squeeze casting process parameters mold-filling ability theoretical calculation experimental evaluation
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Deep-Sea Cobalt Crusts Water Jet Cutting Ability 被引量:1
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作者 Zhonghua Huang Ya Xie 《Geomaterials》 2011年第2期41-45,共5页
Deep-sea cobalt crusts water jet cutting method is proposed to avoid cutter impact load. With simulation calculations and experimental tests, water jet system parameters and its cutting ability were studied. Simula-ti... Deep-sea cobalt crusts water jet cutting method is proposed to avoid cutter impact load. With simulation calculations and experimental tests, water jet system parameters and its cutting ability were studied. Simula-tion results show that working pressure, ejection range and ejection angle of water jet system are main parameters of its cutting ability. Its important degree is in turn the working pressure, ejection range and ejection angle. Increasing water jet system working pressure is the most effective way to improve its cutting ability. When water jet working pressure is constant, in order to improve its cutting ability, the ejection range should be less than 4mm (four times of nozzle diameter) and the ejection angle should be about 13o. Experimental results show that there is a threshold pressure during water jet cutting cobalt crusts simulation material. With the increase of water jet working pressure, its cutting ability increases dramatically. With the increasing of water jet ejection range, its cutting ability decreases sharply. The optimal ejection angle is about 13o</sup. 展开更多
关键词 Water JET System parameters DEEP-SEA COBALT CRUSTS CUTTING ability
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A Modified Glass Formation Criterion for Various Glass Forming Liquids with Higher Reliability
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作者 X. H. Du J. C. Huang 《Chinese Physics Letters》 SCIE CAS CSCD 2007年第5期1335-1338,共4页
A modified indicator of the glass forming ability (GFA) from the previous 7 = Tx/(Tl + Tg) for various glass forming liquids is proposed based on a conceptual approach which combines more acceptable physical meta... A modified indicator of the glass forming ability (GFA) from the previous 7 = Tx/(Tl + Tg) for various glass forming liquids is proposed based on a conceptual approach which combines more acceptable physical metallurgy views in terms of the time-temperature-transformation diagrams. It is found that the glass forming ability for glass forming liquids is closely associated mainly with two factors, i.e. (2Tx - Tg) and Tl (wherein Tx is the onset crystallization temperature, Tg the glass transition temperature, and Tl the liquidus temperature), and could be predicated by a unified parameter γm defined as (2Tx - Tg)/Tl. This approach is confirmed and validated by experimental data in various glass forming systems including oxide glasses, cryoprotectants and metallic glasses, which all shows a higher reliability when their glass forming ability is predicted by the modified parameter. 展开更多
关键词 BULK METALLIC GLASSES ability ALLOYS STability SYSTEMS parameters FRAGILITY
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Least squares fitting of coordinate parameters model
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作者 YU Sheng-wen DONG Jun WANG Ai-min 《中国有色金属学会会刊:英文版》 CSCD 2005年第S1期197-199,共3页
This paper starts with untime-diversification of the time-diversification deformation model and gives displacement distribution model of untime-diversification and simplifies further the study of deformation model.The... This paper starts with untime-diversification of the time-diversification deformation model and gives displacement distribution model of untime-diversification and simplifies further the study of deformation model.The paper discusses the problem of least squares fitting of coordinate parameters model—parameters of deformation model.During discussion,the basic means of cubic B splines and two steps of multidimensional disorder datum fitting are adopted which can make fitting function calculated mostly approximate coordinate parameters model and it can make calculation easier. 展开更多
关键词 coordinate parameter model least squares fitting two steps of multi-dimensional disorder data curve fitting
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Fragility and glass forming ability of Al-Ni-Ce alloy melts
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作者 赵岩 边秀房 +1 位作者 孙民华 张均艳 《中国有色金属学会会刊:英文版》 CSCD 2004年第1期78-81,共4页
The fragility of Al Ni Ce alloy melts with three kinds of different compositions, Al85Ni10Ce5, Al85Ni8Ce7, Al85Ni5Ce10(mole fraction, %), was studied using oscillating vessel viscometer and differential scanning calor... The fragility of Al Ni Ce alloy melts with three kinds of different compositions, Al85Ni10Ce5, Al85Ni8Ce7, Al85Ni5Ce10(mole fraction, %), was studied using oscillating vessel viscometer and differential scanning calorimetry. Their fragility parameters obtained from experiments and theoretic calculation are: 238, 228 and 335 respectively. The results indicate that these three kinds of Al Ni Ce alloy melts are very fragile liquids, which kinetically show strong non Arrhenius behaviour in the Angell plot, so they have poor glass forming ability (GFA). The alloy melt Al85Ni5Ce10 has the largest fragility parameter among the three alloy melts. In the preparation of rapidly quenched amorphous ribbons, Al85Ni10Ce5 and Al85Ni8Ce7 can gain amorphous ribbons when the rotate speed of the roller reaches 800 r/min, while for Al85Ni5Ce10 it must exceed 1 000 r/min. 展开更多
关键词 Al-Ni-Ce合金 稀土 铝合金 脆性 玻璃形成能力
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Complexation of As(Ⅲ)by phosphonate ligands in aqueous fluids:Thermodynamic behavior,chemical binding forms and sequestering abilities
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作者 Donatella Chillè Donatella Aiello +4 位作者 Giuseppa Ida Grasso Ottavia Giuffrè Anna Napoli Carmelo Sgarlata Claudia Foti 《Journal of Environmental Sciences》 SCIE EI CAS CSCD 2020年第8期100-110,共11页
In recent years,the contamination of water by arsenic reached alarming levels in many countries of the world,attracting the interest of many researchers engaged in testing methodologies able to remove this harmful pol... In recent years,the contamination of water by arsenic reached alarming levels in many countries of the world,attracting the interest of many researchers engaged in testing methodologies able to remove this harmful pollutant.An important aspect that must be taken into consideration is the possibility to find arsenic in different chemical forms which could require different approaches for its removal.At this aim,a speciation analysis appears to be crucial for better understanding the behavior of arsenic species in aqueous solutions,especially in presence of compounds with marked chelating properties.Phosphonates can be identified as good sequestering agents and,at this purpose,this manuscript intends to investigate the interaction of As(Ⅲ)with three phosphonic acids derived from nitrilotriacetic acid(NTA)by replacements of one(N-(Phosphonomethyl)iminodiacetic acid,NTAP),two(N,N-Bis-(phosphonomethyl)glycine,NTA2P)and three(Nitrilotri(methylphosphonic acid),NTA3P)carboxylic groups with the same number of phosphonate groups.An in-depth potentiometric and calorimetric investigation allowed to determine speciation models featured by simple ML,MLH i and ML(OH)species.A complete thermodynamic characterization of the systems is reported together with the definition of coordination mode by mass spectrometry measurements.On the light of the speciation models,the possibility of using these ligands in arsenic removal techniques was assessed by determining the pL 0.5(the concentration of ligand able to remove the 50%of metal ion present in trace).All ligands show a good sequestering ability,in particular under the conditions of fresh water,following the trend NTA3P>NTA2P>NTAP. 展开更多
关键词 Phosphonate ligands ARSENIC Thermodynamic interaction parameters Sequestering ability
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可溶性阳极高速镀锡机组锡层均匀性控制策略研究
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作者 王爱红 杨鸿建 +2 位作者 闫建升 张朝磊 宋浩 《电镀与精饰》 北大核心 2025年第2期17-22,共6页
锡层厚度均匀性控制技术对镀锡板的耐蚀性、阳极条纹、白边缺陷等均有明显影响,在镀锡板生产工艺中具有重要意义。针对首钢京唐可溶性阳极高速电镀锡机组,从宏观分散能力和微观分散能力两个方面进行实验研究。结果表明:通过使用“阳极... 锡层厚度均匀性控制技术对镀锡板的耐蚀性、阳极条纹、白边缺陷等均有明显影响,在镀锡板生产工艺中具有重要意义。针对首钢京唐可溶性阳极高速电镀锡机组,从宏观分散能力和微观分散能力两个方面进行实验研究。结果表明:通过使用“阳极错位调节法”,同时调节电镀电流密度为25~27 A/dm^(2)、锡离子浓度调节至16~18 g/L,在实现ATC值和孔隙率显著降低的同时,锡层横向厚度极差降低至10%以内,锡层均匀性得到显著提高。 展开更多
关键词 镀锡板 镀层厚度均匀性 分散能力 可溶性阳极 电镀参数
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干旱与下部遮阴对棉花上部叶片光能利用能力的影响 被引量:1
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作者 简金金 崔宁 +2 位作者 刘天阳 张旺锋 张亚黎 《棉花学报》 北大核心 2025年第2期141-152,共12页
【目的】探究干旱胁迫与下部遮阴及其互作对棉花叶片光能利用能力的影响。【方法】以新陆早80号棉花品种为材料,在人工气候室内测定干旱胁迫和下部叶片遮阴条件下棉花的株高、叶面积、叶片厚度、叶绿素含量以及叶绿素荧光参数等光合生... 【目的】探究干旱胁迫与下部遮阴及其互作对棉花叶片光能利用能力的影响。【方法】以新陆早80号棉花品种为材料,在人工气候室内测定干旱胁迫和下部叶片遮阴条件下棉花的株高、叶面积、叶片厚度、叶绿素含量以及叶绿素荧光参数等光合生理指标。【结果】在中度和重度干旱胁迫下,与未遮阴处理相比,棉花下部遮阴处理显著增加株高和下部叶面积,显著降低上部叶面积和下部叶片的厚度,同时增加上部、下部叶片的叶绿素含量,利于提高叶片的光能捕获能力。在中度和重度干旱胁迫下,与未遮阴处理相比,遮阴处理的下部叶片的光系统Ⅱ的实际量子效率、电子传递速率、光化学猝灭系数和非光化学猝灭均降低;其中,遮阴处理的上部叶片的光系统Ⅱ的实际量子效率分别增加19.4%和31.4%,电子传递速率分别增加19.5%和31.4%,光化学猝灭系数分别增加26.2%和34.7%。下部遮阴处理能提高中度和重度干旱胁迫下棉花上部叶片的光化学反应,降低中度干旱胁迫下棉花上部叶片的热耗散,提高重度干旱胁迫下棉花上部叶片的热耗散。【结论】不同干旱胁迫条件下,遮阴处理对上部叶片光合机构的影响不同。中度干旱胁迫下,系统调控有助于提高棉花上部叶片的光能利用能力。 展开更多
关键词 干旱胁迫 棉花 遮阴 系统信号 光能利用能力 叶绿素荧光参数 光保护
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8份籼型水稻恢复系主要农艺性状的配合力及遗传参数分析
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作者 苏锐 邹梦思 +5 位作者 黎江凤 罗靖凯 李婷 宋子健 唐文帮 张桂莲 《杂交水稻》 北大核心 2025年第2期8-14,共7页
以8份籼型恢复系及对照9311为父本,3份不育系为母本,按不完全双列杂交试验设计配制27个杂交组合,对其进行农艺性状的配合力及遗传参数分析。结果表明,8W1486、8W1484、8W227、R1576表现出较高的GCA效应值,配合力好,有利于培育出产量高... 以8份籼型恢复系及对照9311为父本,3份不育系为母本,按不完全双列杂交试验设计配制27个杂交组合,对其进行农艺性状的配合力及遗传参数分析。结果表明,8W1486、8W1484、8W227、R1576表现出较高的GCA效应值,配合力好,有利于培育出产量高的组合;展998S/8W1484与卓234S/8W1486的单株产量SCA效应值高,且单株产量的表型值也高,具有较好的产量优势;亲本一般配合力和组合特殊配合力之间无明显的相关性;株高、穗长、每穗总粒数、结实率、单株产量的亲本GCA基因型方差贡献率大于杂交组合SCA基因型方差贡献率,主要受基因加性效应影响,单株有效穗数、千粒重的杂交组合SCA基因型方差贡献率大于亲本GCA基因型方差贡献率,主要受基因非加性效应影响;株高、单株有效穗数、穗长、每穗总粒数、结实率、千粒重、单株产量均主要受控于父本的遗传;株高、千粒重、穗长的遗传力大,在后代遗传的稳定性好,宜低世代选择;每穗总粒数、结实率的遗传力较低,宜高世代选择。因此,在育种实践中要同时兼顾高配合力亲本的选择与组合特殊配合力的筛选,才能有效利用水稻杂种优势。 展开更多
关键词 杂交水稻 籼型恢复系 农艺性状 配合力 遗传参数
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基于工业大模型的新能源装备健康状态估计方法
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作者 董芯燚 张泽辉 +5 位作者 左彬 刘洲 徐晓滨 郑梁 侯平智 管聪 《中国舰船研究》 北大核心 2025年第6期126-134,共9页
[目的]针对当前舰船新能源装备健康状态(SOH)估计方法在跨设备泛化能力和模型适配复杂度方面的局限性,提出一种基于工业大模型的新能源装备健康状态估计方法,旨在通过统一框架和参数高效微调策略,快速构建专用估计模型,实现高精度的健... [目的]针对当前舰船新能源装备健康状态(SOH)估计方法在跨设备泛化能力和模型适配复杂度方面的局限性,提出一种基于工业大模型的新能源装备健康状态估计方法,旨在通过统一框架和参数高效微调策略,快速构建专用估计模型,实现高精度的健康状态估计。[方法]基于预训练的Transformer架构构建工业大模型,结合注意力机制和低秩参数微调技术(LoRA),动态调整关键参数以满足不同任务需求。该方法通过滑动窗口注意力机制捕捉局部动态特性,条件化注意力机制融合环境条件影响,并利用LoRA模块快速适配新设备任务。[结果]在锂电池(LIB)和燃料电池(FC)两类典型新能源装备中进行验证实验,结果表明,该方法在锂电池数据集中的平均绝对误差不超过0.0216,决定系数不低于0.9713;在燃料电池数据集中的平均绝对误差不超过0.0033,决定系数不低于0.9197。该工业大模型展现出优异的估计精度和泛化能力。[结论]基于工业大模型的方法能有效提升新能源装备健康状态估计的准确性和可靠性,为设备健康管理提供新的技术手段。未来可在模型优化、跨设备适配和数据处理等方面进一步提升模型性能。 展开更多
关键词 锂电池 燃料电池 设备健康监测 状态估计 工业大模型 深度学习 低秩适配 参数微调 泛化能力 大语言模型
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Numerical simulation analysis of E-Ex mode of the wide-field electromagnetic method for identifying deep,low-resistance thin layers
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作者 Liu Guang-Di Tian Hong-Jun 《Applied Geophysics》 2025年第4期1125-1140,1495,共17页
Shale gas reservoirs have large burial depths,thin thickness,and low resistance,which lead to problems with weak surface observation,abnormal information,and multiple inversion solutions.The traditional electromagneti... Shale gas reservoirs have large burial depths,thin thickness,and low resistance,which lead to problems with weak surface observation,abnormal information,and multiple inversion solutions.The traditional electromagnetic method cannot effectively identify information from deep,low-resistance thin layers in terms of detection depth and accuracy.Wide field electromagnetic method(WFEM)with large depth and high precision has become the main method for deep earth exploration.This method has been widely used in the exploration of deep oil and gas energy,as well as mineral resources.However,an in-depth analysis of the various factors that affect the deep detection ability of WFEM is lacking.Therefore,the analysis of system parameters has significant theoretical importance and practical value for studying the effectiveness of WFEM in deep-layer identification.In this study,a multilayer geoelectric model is established in this study using the measured well data.The influence characteristics of different observation system parameters on the resolution of specific deep-seated targets under the WFEM_E-Ex mode are analyzed in detail through forward modeling and inversion.Results show that the resolution ability of WFEM for deep,low-resistance thin layers is affected by factors such as transceiver distance,target layer thickness,and resistivity difference between the target body and the surrounding rock,but the influence range differs.This study analyzes the influence characteristics of various system parameters.It provides targeted work scheme design and feasibility analysis for deep shale gas exploration.It also offers an important theoretical basis for optimizing construction schemes and improving the recognition ability of WFEM for deep,low-resistance targets. 展开更多
关键词 E-Ex mode Deep detection System parameters Low-resistance thin layer Numerical simulation Identification ability
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汉语作为第二语言听力能力描述语研究——基于中外语言能力标准对比的视角
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作者 韩晓明 《语言教育》 2025年第3期93-105,132,共14页
本研究以听力能力描述语为切入点,从横向参数框架和纵向典型特征两个维度考察,比较五部中外语言能力标准,发现三部汉语能力标准中的听力能力描述语存在描述参数不足、典型特征存在“断层”、描述元语言存在模糊性和重复性等问题,提出“... 本研究以听力能力描述语为切入点,从横向参数框架和纵向典型特征两个维度考察,比较五部中外语言能力标准,发现三部汉语能力标准中的听力能力描述语存在描述参数不足、典型特征存在“断层”、描述元语言存在模糊性和重复性等问题,提出“建立听力描述语库,增加描述参数”和“增强听力能力标准的实证研究,加强效度验证”的建议。 展开更多
关键词 语言能力标准 听力能力 描述语 参数框架
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恩施连续重力观测对地震的记录能力及频谱特征分析
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作者 钱庚 王建伟 +4 位作者 姜楚峰 覃鹏 徐志辉 周诗 胡苗 《科学技术创新》 2025年第12期75-79,共5页
以恩施连续重力基准站半径3500 km的圆内为研究区,选取2014-2017年MS≥2.0地震的目录,分析恩施台gPhone连续重力仪对地震的记录能力和同震响应特征,同时在频域内分析不同的地震参数和观测环境对gPhone记录地震能力的影响。结果表明:恩施... 以恩施连续重力基准站半径3500 km的圆内为研究区,选取2014-2017年MS≥2.0地震的目录,分析恩施台gPhone连续重力仪对地震的记录能力和同震响应特征,同时在频域内分析不同的地震参数和观测环境对gPhone记录地震能力的影响。结果表明:恩施gPhone重力仪更加适用于400 km内的小震及全国5级以上地震的大范围研究工作;经过洋壳传播的地震波衰减慢,更容易被重力仪记录到。随着震中距的增大,地震重力PSD值的优势频段逐渐向低频方向移动,与非震序列PSD明显不同;地震频段的背景噪声水平增大,会导致重力仪对地震的记录能力减弱,使得地震信号湮没在背景噪声中。 展开更多
关键词 重力观测 地震参数 记录能力 频谱特征
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八份甜糯双隐玉米自交系配合力及遗传参数分析
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作者 夏清清 蒲全波 +3 位作者 金容 刘柏宏 符鹏 李仕伟 《热带农业科学》 2025年第8期30-35,共6页
为准确评价甜糯双隐玉米新自交系的应用潜力和利用方向,培育优良甜糯玉米品种,以8份甜糯双隐玉米自交系(F1~F8)为被测系和18份糯玉米自交系(M1~M18)为测验种,按不完全双列杂交配制144个组合,对单株产量、穗长、秃尖等6个主要穗部性状进... 为准确评价甜糯双隐玉米新自交系的应用潜力和利用方向,培育优良甜糯玉米品种,以8份甜糯双隐玉米自交系(F1~F8)为被测系和18份糯玉米自交系(M1~M18)为测验种,按不完全双列杂交配制144个组合,对单株产量、穗长、秃尖等6个主要穗部性状进行配合力及遗传参数分析。结果表明,F4(TN212)除秃尖一般配合力(GCA)为负值外,其他性状均为正效应,综合表现较好;F1(ZTN32)、F2(TN1704)和F3(TN512)单株产量GCA表现较高,易配制出高产组合。M11×F7(ZB102×TN441)主要性状特殊配合力(SCA)均表现优异,是强优势组合;M5×F2(BN211×TN1704)、M16×F3(GN61×TN512)、M14×F4(BN170×TN212)和M10×F8(M10×TN1043)的单株产量SCA表现突出,具有较高产量潜力。八份甜糯双隐玉米自交系穗长、穗行数、单株产量的广义遗传力和狭义遗传力均高于50%;秃尖及行粒数广义遗传力均高于80%,远大于狭义遗传力;穗粗广义遗传力及狭义遗传力均小于50%。以上说明,TN212是较为理想的育种材料,在育种实践中可重点利用;ZTN32、TN1704、TN512应根据育种目标选择相应的亲本材料进行定向利用。穗长、穗行数及单株产量宜在早代选择,秃尖及行粒数宜在晚代选择,穗粗宜在晚代多环境条件下进行选择。 展开更多
关键词 甜糯玉米 自交系 配合力 遗传参数
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基于BP神经网络的地铁盾构掘进参数预测研究
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作者 刘桂东 《地基处理》 2025年第2期201-208,212,共9页
盾构法施工技术已广泛应用于城市地铁建设,建立盾构掘进参数预测模型在减小施工不确定性、保证盾构机安全高效掘进方面具有重要意义。本文基于杭州某在建隧道工程,以地层实际参数与盾构机预设指标等7项参数为网络输入特征,以盾构机掘进... 盾构法施工技术已广泛应用于城市地铁建设,建立盾构掘进参数预测模型在减小施工不确定性、保证盾构机安全高效掘进方面具有重要意义。本文基于杭州某在建隧道工程,以地层实际参数与盾构机预设指标等7项参数为网络输入特征,以盾构机掘进参数等4项参数为输出特征,针对该工程构建了一系列不同超参数组合架构的BP神经网络。通过对比模型在验证集上的表现,选取最适用于该工程的盾构掘进参数预测模型,并在测试集上验证模型的泛化能力。随后,针对5类模型超参数开展了敏感性分析,探究超参数取值对BP神经网络泛化能力的影响。结果表明:该模型对于盾构掘进时的注浆量、出土量、总推力及注浆压力的预测效果均较好;训练批次越大或训练轮次和神经元数量越小,模型总体泛化能力越强,而学习率和隐藏层数量越大时,模型总体泛化能力分别呈现两端大、中间小的U型分布和两端小、中间大的钟型分布。 展开更多
关键词 BP神经网络 盾构隧道掘进参数 预测模型 泛化能力
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社区糖尿病患者依托“浙里护理”的中医治未病健康管理
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作者 周晓英 张新玉 +5 位作者 周琴 汪俐娜 颜佳金 陆建花 罗冬艳 缪晓明 《护理学杂志》 北大核心 2025年第16期57-60,95,共5页
目的探讨依托“浙里护理”的中医治未病健康管理模式对社区2型糖尿病患者中医证候积分及血糖代谢的影响。方法将140例社区2型糖尿病患者随机分为对照组与观察组各70例。对照组给予社区2型糖尿病常规健康管理,观察组在对照组基础上依托... 目的探讨依托“浙里护理”的中医治未病健康管理模式对社区2型糖尿病患者中医证候积分及血糖代谢的影响。方法将140例社区2型糖尿病患者随机分为对照组与观察组各70例。对照组给予社区2型糖尿病常规健康管理,观察组在对照组基础上依托“浙里护理”进行中医治未病健康管理。两组均干预6个月。干预前后比较两组血糖、中医证候积分、糖尿病知识、糖尿病自我管理行为、神经电生理指标的变化及临床疗效。结果干预6个月,观察组空腹血糖及糖化血红蛋白水平显著低于对照组(均P<0.05);干预12周、干预6个月观察组中医证候积分显著低于对照组(组间、时间、交互效应均P<0.05);干预6个月,观察组糖尿病知识、糖尿病自我管理行为及临床有效率(94.29%)显著高于对照组,神经电生理指标显著优于对照组(均P<0.05)。结论依托“浙里护理”的中医治未病健康管理模式,可有效调控2型糖尿病患者的血糖水平,降低中医证候积分,提升患者糖尿病知识水平和自我管理能力,改善神经电生理指标。 展开更多
关键词 2型糖尿病 中医证候 血糖代谢 健康管理 自我管理能力 神经电生理指标 社区护理 互联网+护理
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玉米穗部产量性状配合力和遗传参数分析 被引量:23
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作者 焦仁海 刘兴贰 +3 位作者 孙发明 徐艳荣 侯宗运 才卓 《玉米科学》 CAS CSCD 北大核心 2008年第6期24-28,共5页
以来自不同杂种优势群的10个自交系为供试材料,按Griffing双列杂交方法Ⅳ组配成45个杂交组合。对穗部产量性状进行配合力、遗传参数分析,并对亲本和组合进行了评价,筛选出了优良亲本和优势组合。
关键词 玉米 配合力 遗传参数
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