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Experimental and Numerical Studies of Vitiated Air Effects on Hydrogen-fueled Supersonic Combustor Performance 被引量:7
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作者 LUO Feiteng SONG Wenyan +2 位作者 ZHANG Zhiqiang LI Weiqiang LI Jianping 《Chinese Journal of Aeronautics》 SCIE EI CSCD 2012年第2期164-172,共9页
This paper deals with the vitiation effects of test air on the scramjet performance in the ground combustion heated facilities. The primary goal is to evaluate the effects of H2O and CO2, the two major vitiated specie... This paper deals with the vitiation effects of test air on the scramjet performance in the ground combustion heated facilities. The primary goal is to evaluate the effects of H2O and CO2, the two major vitiated species generated by combustion heater, on hydrogen-fueled supersonic combustor performance with experimental and numerical approaches. The comparative experiments in the clean air and vitiated air are conducted by using the resistance heated direct-connected facility, with the typical Mach 4 flight conditions simulated. The H2O and CO2 species with accurately controlled contents are added to the high enthalpy clean air from resistance heater, to synthesize the vitiated air of a combustion-type heater. Typically, the contents of H2O species can be varied within the range of 3.5%-30% by mole, and 3.0%-10% for CO2 species. The total temperature, total pressure, Mach number and O2 mole fraction at the combustor entrance are well-matched between the clean air and vitiated air. The combustion experiments are completed at the fuel equivalence ratios of 0.53 and 0.42 respectively. Furthermore, three-dimensional (3D) reacting flow simulations of combustor flowpath are performed to provide insight into flow field structures and combustion chemistry details that cannot resolved by experimental instruments available. Finally, the experimental data, combined with computational results, are employed to analyze the effects of H2O and CO2 vitiated air on supersonic combustion characteristics and performance. It is concluded that H2O and CO2 contaminants can significantly inhibit the combustion induced pressure rise measured from combustor wall, and the pressure profile decreases with the increasing H2O and CO2 contents in nonlinear trend; simulation results agree well with experimental data and the overall vitiation effects are captured; direct extrapolation of the results from vitiated air to predict the performance of actual flight conditions could result in over-fueling the combustor, possible inlet un-start and inappropriate combustion mode transition. The detailed analysis and discussion are presented and the research conclusions are summarized. 展开更多
关键词 SCRAMJET HYDROGEN supersonic combustion vitiation effects experimental investigation numerical simulation
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Clinical and Experimental Study on Effect of Garlicin in Treating Angina Pectorls 被引量:2
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作者 史载祥 《Chinese Journal of Integrated Traditional and Western Medicine》 2003年第2期92-92,共1页
Objective: To observe the effect and mechanism of Garlicin in treating coronary heart disease (CHD) with angina pectoris. Methods: Clinical study: 55 patients were selected and randomized into the Garlicin group and t... Objective: To observe the effect and mechanism of Garlicin in treating coronary heart disease (CHD) with angina pectoris. Methods: Clinical study: 55 patients were selected and randomized into the Garlicin group and the nitroglycerin group. To Garlicin group, 60 mg of Garlicin was given by adding in 5% glucose solution for intravenous dripping once per day, the therapeutic course 展开更多
关键词 of in were Clinical and experimental Study on effect of Garlicin in Treating Angina Pectorls on
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EXPERIMENTAL RESEARCH ON THE ANTI-CANCER IMMUNOMODULA-TIVE EFFECT OF THE POLYSOCOHARIBE-PEPTIDE OF CORIOLUS VERSICOLOR 被引量:1
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作者 许良中 杨庆尧 +4 位作者 周金煦 陈瑞婷 李晓玉 胡玉娟 王筠默 《Chinese Journal of Cancer Research》 SCIE CAS CSCD 1989年第2期10-15,共6页
Polysocoharibe-peptide of Coriolus Versicolor (PSP) is a new anti-cancer immunomodulative drug. The present paper reports on the experimental research done with this drug. It was found that PSP had the ability to reco... Polysocoharibe-peptide of Coriolus Versicolor (PSP) is a new anti-cancer immunomodulative drug. The present paper reports on the experimental research done with this drug. It was found that PSP had the ability to recover hemolysin HC50, to increase the weight of the thymus, and increase the alexin of serum C3 and the IgG content of tumor bearing mice. FSP also significantly raised the pha-gocytic activity of macrophages in normal mice. PSP had a significant inhibitory effect on P38S and S180 cells. At the concentration of 1 mg/ml, PSP inhibited the proliferating activity of some human tumor call lines, such as SGC 7901, SPC, SLY and Mei. It had a direct toxic effect on SPC cells. PSP significantly inhibited the synthesis of nucleic acids of Ehrlich ascites carcinoma cells. In addition, PSP was antagonistic to the side effects of chemotherapy and radiotherapy. 展开更多
关键词 PSP experimentAL RESEARCH ON THE ANTI-CANCER IMMUNOMODULA-TIVE effect OF THE POLYSOCOHARIBE-PEPTIDE OF CORIOLUS VERSICOLOR SPC
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Study on effect of HDL on experimental atheroslerosis in rabbits
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《中国输血杂志》 CAS CSCD 2001年第S1期423-,共1页
关键词 HDL Study on effect of HDL on experimental atheroslerosis in rabbits
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Effect of Wave Accessibility on Lower Hybrid Wave Current Drive in Experimental Advanced Superconductor Tokamak with H-Mode Operation 被引量:1
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作者 李新霞 项农 甘春芸 《Chinese Physics Letters》 SCIE CAS CSCD 2015年第3期74-77,共4页
The effect of the wave accessibility condition on the lower hybrid cm'rent drive in the experimental advanced superconductor Tokamak (EAST) plasma with H-mode operation is studied. Based on a simplified model, a mo... The effect of the wave accessibility condition on the lower hybrid cm'rent drive in the experimental advanced superconductor Tokamak (EAST) plasma with H-mode operation is studied. Based on a simplified model, a mode conversion layer of the lower hybrid wave between the fast wave branch and the slow wave branch is proved to exist in the plasma periphery for typical EAST H-mode parameters. Under the framework of the lower hybrid wave simulation code (LSC), the wave ray trajectory and the associated current drive are calculated numerically. The results show that the wave accessibility condition plays an important role on the lower hybrid current drive in EAST plasma. For wave rays with parallel refractive index n||= 2.1 or n|| = 2.5 launched from the outside midplane, the wave rays may penetrate the core plasma due to the toroida] geometry effect, while numerous reflections of the wave ray trajectories in the plasma periphery occur. However, low current drive efficiency is obtained. Meanwhile, the wave accessibility condition is improved if a higher confined magnetic field is applied. The simulation results show that for plasma parameters under present EAST H-mode operation, a significant lower hybrid wave current drive could be obtained for the wave spectrum with peak value n|| = 2.1 if a toroidal magnetic field BT =2.5 T is applied. 展开更多
关键词 effect of Wave Accessibility on Lower Hybrid Wave Current Drive in experimental Advanced Superconductor Tokamak with H-Mode Operation
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A Fluid Experiment of Large-Scale Topography Effect on Baroclinic Wave Flows
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作者 李国庆 Robin Kung Richard L.Pfeffer 《Advances in Atmospheric Sciences》 SCIE CAS CSCD 1992年第1期17-28,共12页
The effects of topography on baroclinic wave flows are studied experimentally in a thermally driven rotating annulus of fluid.Fourier analysis and complex principal component (CPC) analysis of the experimental data sh... The effects of topography on baroclinic wave flows are studied experimentally in a thermally driven rotating annulus of fluid.Fourier analysis and complex principal component (CPC) analysis of the experimental data show that, due to topographic forcing, the flow is bimodal rather than a single mode. Under suitable imposed experimental parameters, near thermal Rossby number ROT = 0.1 and Taylor number Ta = 2.2 × 107, the large-scale topography produces low-frequency oscillation in the flow and rather long-lived flow pattern resembling blocking in the atmospheric circulation. The 'blocking' phenomenon is caused by the resonance of travelling waves and the quasi-stationary waves forced by topography.The large-scale topography transforms wavenumber-homogeneous flows into wavenumber-dispersed flows, and the dispersed flows possess lower wavenumbers. 展开更多
关键词 A Fluid experiment of Large-Scale Topography effect on Baroclinic Wave Flows
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Experimental Studies of the Doppler Effect
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作者 L. A. Pobedonostsev (Radium Institute, Pr. Shvernika 28, 194021 St. Petersburg, Russia) 《Journal of Systems Engineering and Electronics》 SCIE EI CSCD 1995年第4期115-128,共14页
Recent experimental results of the Doppler effect formula verification are reported. The moving emitters are hydrogen atoms in the excited state. The results of the work corroborate the classical not the relativistic,... Recent experimental results of the Doppler effect formula verification are reported. The moving emitters are hydrogen atoms in the excited state. The results of the work corroborate the classical not the relativistic,formula for the Doppler effect. 展开更多
关键词 Doppler effect Hydrogen atom experimental results Relativity.
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Experimental Study on the Effect of Sediment Composition Ratio on Shallow Water Delta
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作者 ZENG Can YIN Taiju +1 位作者 SONG Yakai YAN Xiujin 《Acta Geologica Sinica(English Edition)》 SCIE CAS CSCD 2017年第S1期146-147,共2页
1 Introduction Shallow water delta in the middle-newborn Stratum Widely developed with huge oil and gas in China(Hu Shengwu et al.,2013).The control factors on the deltadevelopment like Climate,sea level,tectonic subs... 1 Introduction Shallow water delta in the middle-newborn Stratum Widely developed with huge oil and gas in China(Hu Shengwu et al.,2013).The control factors on the deltadevelopment like Climate,sea level,tectonic subsidence,sediment supply(flow,type),the geometric characteristics of the upstream river,the energy(wave, 展开更多
关键词 experimental Study on the effect of Sediment Composition Ratio on Shallow Water Delta
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Experimental study of protective effects of magnetic field on blood stored at 4℃
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《中国输血杂志》 CAS CSCD 2001年第S1期351-,共1页
关键词 experimental study of protective effects of magnetic field on blood stored at 4
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Experimental study on effect of endothelin in the proliferation and collagen synthesis of human scar-derived fibroblasts
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作者 刘德伍 《外科研究与新技术》 2003年第2期124-125,共2页
Objective To investigate the role of endothelin(ET) in the proliferation and collagen synthesis of human scar-derived fibroblasts and the moduktion of its antagonists such as nitric oxide(NO), tetrandrine ( Tet). Meth... Objective To investigate the role of endothelin(ET) in the proliferation and collagen synthesis of human scar-derived fibroblasts and the moduktion of its antagonists such as nitric oxide(NO), tetrandrine ( Tet). Methods With the cultured fibroblasts from the scarring tissue, the cell pdiferation was determined by[3H]-TdR incorporation, while the collagen synthesis was evaluated by[3H]-proline incorporation. Results The ET-1 was significantly increasing the proliferation and collagen synthesis of human scar-derived fibroblasts. The values of [3H]-TdR absorption in the 2.5 ng/ml,25 ng/ml and 100 ng/ml of ET-1 groups were 1.8 times,4 times and 4.9 times more than in the control group, respectively(P【0. 01),while the values of the [3H]-proline incorporation were 1.1 times,3.1 times and 3.8 times respectively(P【0.01). The fibroblasts, treated with 50 μg/ml of S-nitroso-N-acetyl penicillamine(SNAP), were no detectable effect on the basal level of DNA synthesis,but produced decreasing effect on the 展开更多
关键词 of experimental study on effect of endothelin in the proliferation and collagen synthesis of human scar-derived fibroblasts
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Experimental study of the effect of adipose stromal vascular fraction cells on the survival rate of fat transplantation
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作者 付冰川 《外科研究与新技术》 2011年第2期132-132,共1页
Objective To investigate the effect of adipose stromal vascular fraction cells(SVFs)on the survival rate of fat ransplantation.Methods 0.5mL autologous fat tissue was mixed with: ① DiI-labeled autologous SVFs (Group ... Objective To investigate the effect of adipose stromal vascular fraction cells(SVFs)on the survival rate of fat ransplantation.Methods 0.5mL autologous fat tissue was mixed with: ① DiI-labeled autologous SVFs (Group A);② 展开更多
关键词 rate ASCs experimental study of the effect of adipose stromal vascular fraction cells on the survival rate of fat transplantation
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An experimental study on preventive effect of continuous irrigation from peridural adhesion after laminectomy
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作者 马泉 《外科研究与新技术》 2011年第2期93-93,共1页
Objective To observe the preventive effect of continuous irrigation with sodium hyaluronate injection from peridural adhesionaminectomy.Methods Larninectomies were performed in L1,L4,L7 of 25 New Zealand rabbits respe... Objective To observe the preventive effect of continuous irrigation with sodium hyaluronate injection from peridural adhesionaminectomy.Methods Larninectomies were performed in L1,L4,L7 of 25 New Zealand rabbits respectively with 3 展开更多
关键词 An experimental study on preventive effect of continuous irrigation from peridural adhesion after laminectomy
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基于认知负荷理论的计算机组成原理实验教学设计与应用 被引量:2
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作者 杨磊 司国东 +3 位作者 王春桃 黄沛杰 肖克辉 杜治国 《实验室研究与探索》 北大核心 2025年第1期177-181,共5页
计算机组成原理实验教学能提高学生系统设计及应用创新能力,但因其实验原理抽象、知识点多,实验平台复杂等特点也让学生在实验过程中产生较高的认知负荷。为解决高认知负荷对实验教学造成的负面影响,基于认知负荷理论对实验进行教学设计... 计算机组成原理实验教学能提高学生系统设计及应用创新能力,但因其实验原理抽象、知识点多,实验平台复杂等特点也让学生在实验过程中产生较高的认知负荷。为解决高认知负荷对实验教学造成的负面影响,基于认知负荷理论对实验进行教学设计,分析学生学习需要因材施教控制学生内部认知负荷,优化实验教材设计及呈现方式降低学生外部认知负荷,激发学生学习兴趣以提高学生相关认知负荷,提升实验教学效果。教学实践表明,新型教学设计有效降低学生实验过程中的认知负荷总量,计算机系统设计及创新能力得到较高的提升。此方法也可为其他实验课程教学改革提供参考。 展开更多
关键词 计算机组成原理 认知负荷理论 实验教学 成效研究
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AuPt双金属催化氧化乙二醇制备乙醇酸综合实验设计
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作者 闫昊 杨诗轩 +4 位作者 冯翔 刘熠斌 陈小博 赵辉 杨朝合 《实验技术与管理》 北大核心 2025年第8期210-216,共7页
基于“科教融合”理念及相关科研成果,设计了“AuPt双金属催化氧化乙二醇制备乙醇酸”综合实验。该综合实验以高效合成乙醇酸为主要目标,探究了不同Au/Pt比对催化剂催化性能的影响,得到了最优Au/Pt比,通过材料表征探究了材料结构与催化... 基于“科教融合”理念及相关科研成果,设计了“AuPt双金属催化氧化乙二醇制备乙醇酸”综合实验。该综合实验以高效合成乙醇酸为主要目标,探究了不同Au/Pt比对催化剂催化性能的影响,得到了最优Au/Pt比,通过材料表征探究了材料结构与催化性能之间的关系。该综合实验设计结合了多种学科知识,涉及材料制备、材料表征、性能评价等诸多内容,有助于巩固学生的理论知识,提升学生的科研素养,并在实践过程中培养创新思维、实践操作能力和批判思维,促进教学质量提升。 展开更多
关键词 乙醇酸 无碱氧化 结构效应 实验设计
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以赛促学提升遗传学实验教学质量 被引量:1
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作者 魏远 王宏刚 +3 位作者 朱玉山 李艳君 李登文 赵念席 《生物学杂志》 北大核心 2025年第2期127-130,共4页
实验技能竞赛重在考查学生基础实验操作和对知识的综合运用能力,是对实验教学质量和学生的双重检验。课程组以天津市大学生生命科学竞赛的“摇蚊幼虫唾腺多线染色体的制备及观察”比赛项目作为切入点,将竞赛选手选拔和培训环节与实验教... 实验技能竞赛重在考查学生基础实验操作和对知识的综合运用能力,是对实验教学质量和学生的双重检验。课程组以天津市大学生生命科学竞赛的“摇蚊幼虫唾腺多线染色体的制备及观察”比赛项目作为切入点,将竞赛选手选拔和培训环节与实验教学相融合,利用学生的积极主动性,拓展第二课堂,强化基础和细节训练,培养学生深入发现和解决问题的能力。面向参赛选手发放问卷调研参赛收获,分析选手的竞赛成绩和实验课程成绩。结果表明,实验竞赛能够以赛促学,使学生主动锻炼操作技能,夯实基础,促进实验教学质量提升。 展开更多
关键词 实验竞赛 遗传学实验 教学质量 成绩分析 多线染色体
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基于倾角效应的“支架-围岩”数字孪生模拟试验平台研制与测试 被引量:1
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作者 解盘石 张颖异 +7 位作者 伍永平 杜玉乾 杨航 黄宝发 林伟典 易磊磊 徐辉 冯春 《煤炭学报》 北大核心 2025年第6期2837-2852,共16页
液压支架与围岩两者间的稳定性关系是长壁工作面开采及其智能化研究的重难点内容之一。大倾角、急倾斜煤层赋存条件复杂,“支架-围岩”稳定性控制难度大,严重制约了该类复杂难采煤层矿井的安全智能开采。为此,在实验室环境下研制了三维... 液压支架与围岩两者间的稳定性关系是长壁工作面开采及其智能化研究的重难点内容之一。大倾角、急倾斜煤层赋存条件复杂,“支架-围岩”稳定性控制难度大,严重制约了该类复杂难采煤层矿井的安全智能开采。为此,在实验室环境下研制了三维大比例模拟试验平台与配套试验液压支架,可最大程度模拟复杂难采煤层工作面的开采环境,工作面“支架-围岩”系统耦合控制、顶板周期来压及冲击来压效果。基于数字孪生技术,构建了“支架-围岩”试验平台孪生系统,可实现对物理空间模拟试验工作面“支架-围岩”系统的精确感知与高效仿真。开展了试验平台性能、异型液压支架研发支撑、“支架-围岩”试验平台孪生系统优化等一系列测试试验,确定了试验平台整体结构的稳定性和性能的可靠性、孪生系统的实用性和准确性,体现了试验平台的多功能性。基于测试试验,发现工作面顶板来压期间,支架在倾角效应下易发生侧向偏转失稳,支架间侧向挤压加剧;工作面顶板、支架、煤壁及底板组成的“支架-围岩”系统是协同承载体,四者任何环节变化都会影响整体的稳定性,也会加剧另外环节的破坏。针对性提出采取液压支架防倒滑装置、加强围岩控制和实时监测预警3项改进措施,来提升复杂煤层工作面“支架-围岩”系统的整体稳定性。 展开更多
关键词 数字孪生 支架-围岩 倾角效应 大比例模拟试验平台 智能化 大倾角煤层
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基于虚拟仿真技术的实验教学发展路径探索 被引量:2
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作者 郭松 车红连 《教育教学论坛》 2025年第17期109-112,共4页
随着我国教育信息化的快速发展,虚拟仿真技术因其独特的优势在高校实验教学中得到广泛应用。在总结我国虚拟仿真实验项目建设现状的基础上,深入分析目前虚拟仿真实验项目在发展过程中存在的缺乏系统思维,重建设轻管理、缺乏有效评价机制... 随着我国教育信息化的快速发展,虚拟仿真技术因其独特的优势在高校实验教学中得到广泛应用。在总结我国虚拟仿真实验项目建设现状的基础上,深入分析目前虚拟仿真实验项目在发展过程中存在的缺乏系统思维,重建设轻管理、缺乏有效评价机制,开放共享程度低、利用率不高等问题,进而在建设思路、管理手段、评价方法、共享推广等方面提出建议对策,既进一步丰富了现有虚拟仿真实验教学理论研究的成果,又为后续虚拟仿真项目发展提供了决策依据,有利于虚拟仿真技术在教育领域中的广泛深入运用和更好地发挥作用。 展开更多
关键词 虚拟仿真 实验教学 教学效果
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典型无源干扰电磁散射研究进展综述
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作者 郭立新 左炎春 刘伟 《电波科学学报》 北大核心 2025年第4期628-650,共23页
高对抗环境下的无源干扰电磁散射研究一直是计算电磁学、电子对抗和战场数字孪生等领域中的重要课题,对该问题的深入研究是未来战场红蓝对抗博弈建模、装备设计优化和战术战法升级的重要理论基础。因此,面向新质作战能力生成需求,开展... 高对抗环境下的无源干扰电磁散射研究一直是计算电磁学、电子对抗和战场数字孪生等领域中的重要课题,对该问题的深入研究是未来战场红蓝对抗博弈建模、装备设计优化和战术战法升级的重要理论基础。因此,面向新质作战能力生成需求,开展典型无源干扰电磁散射研究现状梳理与分析具有重要意义。本文对箔条云和角反射器两类典型无源干扰电磁散射研究进展进行了综述和讨论。当前对无源干扰电磁散射建模的研究主要分为四个方面:场景构建,散射计算,试验验证,效能评估。对几何建模的研究集中在干扰物与环境的动力学耦合效应研究方面,对无源干扰物的散射计算集中在大场景分区耦合散射计算方面,对无源干扰散射试验多集中在可控试验及内外场联合试验理论研究方面,对干扰效能评估主要集中在干扰物优化设计与投放策略制定方面。目前,对无源干扰物与环境复合方面的研究依旧面临场景构建逼真度低、仿真计算效率较低、试验验证理论体系不完善、效能评估手段单一、智能化水平不高等问题,这些问题均制约了新质作战能力的生成与提升。需要结合多物理场耦合手段实现无源干扰物与背景复合几何和散射高精度建模,需要引用智能化评估方法实现无源干扰物干扰效能评估与优化设计,需要将可控技术引入内外场试验设计中以实现无源干扰物雷达特性测算融合研究。 展开更多
关键词 无源干扰 几何建模 电磁散射 红蓝对抗 散射试验 效能评估
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硕士研究生英语学习者语音意识训练效果实证研究
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作者 赵洪宝 《吉林师范大学学报(人文社会科学版)》 2025年第4期86-94,共9页
语音意识是个体对不同语言单位的辨别和综合操作能力。语音意识对单词拼写、阅读能力等方面均有显著影响。文章基于实验方式,使用双重差分法分析语言意识训练对于硕士研究生英语学习者语音意识的训练效应。计量分析结果表明:第一,硕士... 语音意识是个体对不同语言单位的辨别和综合操作能力。语音意识对单词拼写、阅读能力等方面均有显著影响。文章基于实验方式,使用双重差分法分析语言意识训练对于硕士研究生英语学习者语音意识的训练效应。计量分析结果表明:第一,硕士研究生英语学习者语音意识能力分布不均,个体差异显著;第二,语音意识操作能力训练对于硕士研究生音韵意识和音节意识操作能力的提高并不显著或者一般显著;第三,硕士研究生音位意识操作能力可以通过系统的语音意识训练得到快速提高;第四,语音意识训练在性别方面无明显差异。 展开更多
关键词 语音意识 研究生英语学习者 训练效果 实验法
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整合利用院系资源活化焊接实验教学
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作者 高党寻 白海林 +4 位作者 彭世广 姚启明 周冰科 徐江波 赵萌 《模具制造》 2025年第1期61-63,共3页
焊接实验是材料加工系列实验的重要一环,具有很强的实践性和工艺性。从我校近年来开展实验教学的实际出发,充分整合利用院系多个实验室教学资源,重整实验教学模块、倡导科研实验模式、强化实验总结环节4个方面论述提高焊接实验课堂教学... 焊接实验是材料加工系列实验的重要一环,具有很强的实践性和工艺性。从我校近年来开展实验教学的实际出发,充分整合利用院系多个实验室教学资源,重整实验教学模块、倡导科研实验模式、强化实验总结环节4个方面论述提高焊接实验课堂教学质量的主要举措。 展开更多
关键词 资源利用 实验教学 内容革新 教学效果
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