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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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Sampled-data control through model-free reinforcement learning with effective experience replay 被引量:2
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作者 Bo Xiao H.K.Lam +4 位作者 Xiaojie Su Ziwei Wang Frank P.-W.Lo Shihong Chen Eric Yeatman 《Journal of Automation and Intelligence》 2023年第1期20-30,共11页
Reinforcement Learning(RL)based control algorithms can learn the control strategies for nonlinear and uncertain environment during interacting with it.Guided by the rewards generated by environment,a RL agent can lear... Reinforcement Learning(RL)based control algorithms can learn the control strategies for nonlinear and uncertain environment during interacting with it.Guided by the rewards generated by environment,a RL agent can learn the control strategy directly in a model-free way instead of investigating the dynamic model of the environment.In the paper,we propose the sampled-data RL control strategy to reduce the computational demand.In the sampled-data control strategy,the whole control system is of a hybrid structure,in which the plant is of continuous structure while the controller(RL agent)adopts a discrete structure.Given that the continuous states of the plant will be the input of the agent,the state–action value function is approximated by the fully connected feed-forward neural networks(FCFFNN).Instead of learning the controller at every step during the interaction with the environment,the learning and acting stages are decoupled to learn the control strategy more effectively through experience replay.In the acting stage,the most effective experience obtained during the interaction with the environment will be stored and during the learning stage,the stored experience will be replayed to customized times,which helps enhance the experience replay process.The effectiveness of proposed approach will be verified by simulation examples. 展开更多
关键词 Reinforcement learning Neural networks Sampled-data control MODEL-FREE effective experience replay
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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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某型高温涡轮叶片冷却性能的实验研究 被引量:1
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作者 赵振 高建民 +2 位作者 徐亮 席雷 李云龙 《西安交通大学学报》 EI CSCD 北大核心 2024年第1期54-67,共14页
为了有效监测高温涡轮叶片的安全运行状态,基于响应面模型对某型高温涡轮叶片进行了实验研究,旨在探究关键工况参数对其冷却性能的影响,以提供可靠的数据支持。采用中心复合表面设计对某型叶片的工况参数进行设计,研究了主流入口温度、... 为了有效监测高温涡轮叶片的安全运行状态,基于响应面模型对某型高温涡轮叶片进行了实验研究,旨在探究关键工况参数对其冷却性能的影响,以提供可靠的数据支持。采用中心复合表面设计对某型叶片的工况参数进行设计,研究了主流入口温度、主流出口压力、主流进出口压比、冷气与主流温度比及流量比对某型叶片冷却效率分布、无量纲温度分布及温度非均匀度的影响规律,并在此基础上构建了响应面模型,探究了工况参数的耦合作用对某型叶片冷却性能的综合影响。实验结果表明:拟合得到的响应面模型有较高的精度,其均方根误差均小于0.001,决定系数均大于0.99;主流入口温度和出口压力对叶片冷却性能的影响均较小;在实验工况范围内,当主流进出口压比、冷气与主流温度比及流量比分别从1.3~1.5、0.6~0.7、3~8增大时,叶片的平均冷却效率分别增大了9.67%、9.39%、30.49%;叶片的平均无量纲温度分别提高了2.98%,降低了1.34%、3.78%;叶片的温度非均匀度分别降低了2.69%、28.79%,提高了50.27%。 展开更多
关键词 涡轮叶片 冷却性能 响应面模型 耦合作用
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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 I-V and C-V Analysis of Schottky-Barrier Metal-Oxide-Semiconductor Field Effect Transistors with Epitaxial NiSi2 Contacts and Dopant Segregation
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作者 王翼泽 刘畅 +4 位作者 蔡剑辉 刘强 刘新科 俞文杰 赵清太 《Chinese Physics Letters》 SCIE CAS CSCD 2017年第7期275-278,共4页
We present an experimental analysis of Schottky-barrier metal-oxide-semiconductor field effect transistors (SB- MOSFETs) fabricated on ultrathin body silicon-on-insulator substrates with a steep junction by the dopa... We present an experimental analysis of Schottky-barrier metal-oxide-semiconductor field effect transistors (SB- MOSFETs) fabricated on ultrathin body silicon-on-insulator substrates with a steep junction by the dopant implantation into the silicide process. The subthreshold swing of such SB-MOSFETs reaches 69mV/dec. Em- phasis is placed on the capacitance-voltage analysis of p-type SB-MOSFETs. According to the measurements of gate-to-source capacitance Cgs with respect to Vgs at various Vds, we find that a maximum occurs at the accumulation regime due to the most imbalanced charge distribution along the channel. At each Cgs peak, the difference between Vgs and Vds is equal to the Schottky barrier height (SBH) for NiSi2 on highly doped silicon, which indicates that the critical condition of channel pinching off is related with SBH for source/drain on chan- nel. The SBH for NiSi2 on highly doped silicon can affect the pinch-off voltage and the saturation current of SB-MOSFETs. 展开更多
关键词 MOSFET experimental I-V and C-V Analysis of Schottky-Barrier Metal-Oxide-Semiconductor Field effect Transistors with Epitaxial NiSi2 Contacts and Dopant Segregation
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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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社交媒体网络辟谣回音室效应分析模型及实验研究
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作者 王晰巍 孙哲 +1 位作者 姜奕冰 李玥琪 《现代情报》 北大核心 2024年第10期3-17,共15页
[目的/意义]社交媒体因其受众广和传播速度快的特点,成为网络谣言传播的重要媒介。鉴于网络谣言的危害性,如何有效控制谣言传播和及时进行辟谣,对网络谣言的辟谣工作和网络空间生态治理具有重要的理论和现实意义。[方法/过程]本文提出... [目的/意义]社交媒体因其受众广和传播速度快的特点,成为网络谣言传播的重要媒介。鉴于网络谣言的危害性,如何有效控制谣言传播和及时进行辟谣,对网络谣言的辟谣工作和网络空间生态治理具有重要的理论和现实意义。[方法/过程]本文提出网络辟谣主题识别及用户情感态度划分的方法,根据LDA算法确定划分主题数,在最优主题数下构建用户层级和社区层级的回音室网络,并给出社交媒体网络辟谣的回音室效应分析模型,确立了回音室效应分析公式及检验参数。结合“东航MU5735坠机”网络舆情话题中网络谣言辟谣数据进行分析,对6个网络辟谣主题进行识别和情感分布进行分析,并结合6个辟谣主题进行用户评论网络与转发网络回音室网络结构进行分析,计算每个辟谣主题下回音室效应的虚拟社区层级的评论网络和转发网络中每个虚拟社区主题的同质性。[结果/结论]研究发现,社交网络中辟谣信息的传播过程中存在回音室效应,其中转发过程比评论过程具有更强的网络同质性,而评论用户比转发用户具有更高的矛盾心理。 展开更多
关键词 社交媒体 网络谣言辟谣 回音室效应 分析模型 实验研究
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自然对流下蒸汽凝结表面传热系数测定实验装置研制
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作者 幸文婷 朱赤 +1 位作者 叶晓明 吴杰俊 《实验技术与管理》 CAS 北大核心 2024年第6期172-176,共5页
自然对流下蒸汽凝结表面传热系数测定实验是将蒸汽通过一组表面状态各不相同的管道,测定管道在大空间空气介质中自然冷却过程中的蒸汽凝结表面传热系数。由于管道的材质、几何形状、接触方式及管外空气流动状况都会不同程度地影响换热效... 自然对流下蒸汽凝结表面传热系数测定实验是将蒸汽通过一组表面状态各不相同的管道,测定管道在大空间空气介质中自然冷却过程中的蒸汽凝结表面传热系数。由于管道的材质、几何形状、接触方式及管外空气流动状况都会不同程度地影响换热效果,因此测定每根管道的表面传热系数值,可条理性和系统性地分析影响传热过程的各因素。该文设计了自然对流下蒸汽凝结表面传热系数测定实验装置,可开展管道材质、肋片结构、管道横截面几何形状、管道保温材料对传热系数的影响实验研究。应用实践表明,实验项目内容全面,提高了学生的课堂积极性,具有良好的教学效果。 展开更多
关键词 蒸汽凝结 表面传热系数 实验项目 教学效果
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应用化学国家级实验教学示范中心建设与实践
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作者 张诺 孙晓君 +5 位作者 马洪敏 李燕 任祥 吴丹 罗川南 魏琴 《大学化学》 CAS 2024年第7期116-120,共5页
基于应用化学国家级实验教学示范中心(济南大学)2018–2022年的建设与实践成果,从管理与运行机制、教学改革研究、实验教学条件、师资队伍建设、示范引领成效等方面,总结分析了示范中心建设的成效与经验,指出了示范中心存在的问题和不足... 基于应用化学国家级实验教学示范中心(济南大学)2018–2022年的建设与实践成果,从管理与运行机制、教学改革研究、实验教学条件、师资队伍建设、示范引领成效等方面,总结分析了示范中心建设的成效与经验,指出了示范中心存在的问题和不足,并对未来发展规划进行了展望。示范中心采用“三段式”培养方式,开展“能力-素养导向型”实验课程,搭建“产·学·研·创”立体化创新实践平台,切实培养了学生的实践能力和创新精神,并且在企事业单位和地方院校的示范辐射中发挥了重要作用。 展开更多
关键词 应用化学 实验教学示范中心 建设成效
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半密闭环境Al/AP对含铝炸药爆炸效应影响实验研究
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作者 王琰 蒋海燕 +2 位作者 储著鑫 李芝绒 苏健军 《兵器装备工程学报》 CAS CSCD 北大核心 2024年第5期202-208,共7页
为了研究铝粉和高氯酸铵(AP)含量对含铝炸药在半密闭环境中的爆炸释能影响规律,开展了6种不同配方复合炸药在半密闭罐内的爆炸实验,并使用高速相机及压力传感器获取了爆炸火球膨胀历程和冲击波参数。实验结果表明,在火球膨胀阶段,铝粉... 为了研究铝粉和高氯酸铵(AP)含量对含铝炸药在半密闭环境中的爆炸释能影响规律,开展了6种不同配方复合炸药在半密闭罐内的爆炸实验,并使用高速相机及压力传感器获取了爆炸火球膨胀历程和冲击波参数。实验结果表明,在火球膨胀阶段,铝粉和AP含量的增加都可以通过增强铝粉的后燃烧过程,进而提高火球高温持续时间和热流密度峰值;铝粉和高氯酸铵(AP)对管道近端测点的超压不做贡献反而会起负面作用,主要是通过增强铝粉后燃烧过程而对之后的测点产生影响;铝粉和高氯酸铵(AP)主要影响管道近端测点冲量,由于铝粉后燃烧过程的结束,对远端测点冲量不做贡献。 展开更多
关键词 半密闭环境 含铝炸药 爆炸效应 实验研究
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气相爆轰波凹面反射过程尺度效应的实验研究
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作者 景天雨 林庚浩 李健 《航天器环境工程》 CSCD 2024年第1期74-81,共8页
了解气相爆轰波的凹面反射是研究爆轰波在环形管道条件下传播机制的基础。文章针对气相爆轰波凹面反射问题中存在的尺度效应进行实验研究,得到三波点轨迹和临界壁角与几何尺度之间的定量关系,发现了类似于爆轰波楔面马赫反射的尺度效应... 了解气相爆轰波的凹面反射是研究爆轰波在环形管道条件下传播机制的基础。文章针对气相爆轰波凹面反射问题中存在的尺度效应进行实验研究,得到三波点轨迹和临界壁角与几何尺度之间的定量关系,发现了类似于爆轰波楔面马赫反射的尺度效应和2个极限(冻结和平衡极限);进一步研究发现尺度效应高度依赖于2个特征长度尺度(胞格尺寸λ和凹面曲率半径R)。以上研究可为高性能航天推进系统燃烧室的设计提供理论参考。 展开更多
关键词 胞格爆轰波 气相爆轰波 凹面反射 马赫反射 尺度效应 实验研究
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基于汉语孤岛现象的大语言模型语言能力评估
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作者 陈旭 司富珍 《昆明学院学报》 2024年第5期21-29,共9页
基于概率来预测下一词的生成式大语言模型因其在语言生成方面的出色性能,使得不少人认为这种模型本质上就是人类语言官能的模型。然而,基于语法规则研究语言的学者则认为,大语言模型并不能洞察人类语言官能的本质。研究以汉语孤岛效应... 基于概率来预测下一词的生成式大语言模型因其在语言生成方面的出色性能,使得不少人认为这种模型本质上就是人类语言官能的模型。然而,基于语法规则研究语言的学者则认为,大语言模型并不能洞察人类语言官能的本质。研究以汉语孤岛效应为切入点,评估了以GPT-2和Gemma 2为代表的大语言模型对这一语言现象的理解能力。我们设计了两组实验。实验一通过量化孤岛效应的影响因子,测试了汉语母语者对孤岛效应的认知。结果表明,母语者能够清晰地察觉出汉语中的孤岛效应,准确判别出汉语不合语法的句式。实验二通过计算最小对比对中违反孤岛和遵守孤岛句子的概率,测试了以上两种模型对孤岛效应的反应。结果表明,GPT-2和Gemma 2虽然可以甄别出两类句子在概率分布上存在差异;但其并不理解概率分布较低,即违反孤岛限制的句子,实际上是母语者根本不会产出的句子。对比以上两组实验,我们认为尽管大语言模型在语言生成方面表现出色,但在理解和判断特定语言现象方面仍然存在局限性,尚未达到人类语言能力水平。 展开更多
关键词 大语言模型 孤岛效应 实验句法学 惊讶值
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