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浮游板优化精液与密度梯度离心结合上游法的比较
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作者 张玲 辜秀丽 +7 位作者 袁周 金其贝 张衷源 叶臻 孟天庆 周慧 李红钢 熊承良 《生殖医学杂志》 CAS 2024年第8期1080-1086,共7页
目的应用浮游板和密度梯度离心结合上游法优化人类精液,明确优化效果并比较两种方法优化后精子参数的差异。方法收集正常精液样本85例和轻中度少弱精子症精液样本59例,每例样本分为原液组、密梯组和浮游组各1 ml进行后续处理。原液组在... 目的应用浮游板和密度梯度离心结合上游法优化人类精液,明确优化效果并比较两种方法优化后精子参数的差异。方法收集正常精液样本85例和轻中度少弱精子症精液样本59例,每例样本分为原液组、密梯组和浮游组各1 ml进行后续处理。原液组在精液液化后未做任何处理;密梯组精液液化后用密度梯度离心法结合上游法进行处理,浮游组则在精液液化后应用精子浮游板进行处理。比较原液组、密梯组、浮游组3个亚组间的精子浓度、前向运动精子百分率、正常形态精子百分率;应用流式细胞仪检测精子线粒体膜电位和精子DNA碎片指数,使用单精子活性氧分析仪检测单精子活性氧水平,使用电子显微镜观察精子超微结构并进行组间比较。结果无论是正常精液还是轻中度少弱精子症精液,与原液组比较,密梯组与浮游组的前向运动精子百分率、正常形态精子百分率及精子线粒体膜电位均显著升高(P<0.05),精子DNA碎片指数显著降低(P<0.05);密梯组和浮游组各指标无显著性差异(P>0.05)。正常精液中,浮游组的精子浓度显著高于密梯组(P=0.029),单精子活性氧水平显著低于原液组(P=0.038)。轻中度少弱精子症精液中3亚组间的单精子活性氧水平均无显著性差异(P>0.05)。电子显微镜观察发现正常精液中3个亚组的精子均未见明显异常;轻中度少弱精子症精液中密梯组部分精子可观察到精子细胞膜断裂和线粒体肿胀等异常,而浮游组精子超微结构未见明显异常。结论密度梯度离心结合上游法和浮游板法用于精液的处理和优化,均可有效回收活力、形态和功能更好的精子。精子浮游板法的体外干预小,操作简便,可以获得活性氧更少、损伤更小的精子。 展开更多
关键词 密度梯度离心法 浮游板法 单精子活性氧 精子DNA碎片指数 精子线粒体膜电位
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家庭代际学习:模式、要素与作用机理
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作者 欧阳忠明 王子鹤 袁舟 《现代远程教育研究》 CSSCI 北大核心 2024年第4期58-66,共9页
家庭代际学习是代际学习在家庭场域中的具体应用,它贯穿家庭的各个生命阶段,是真正意义上的终身学习实践。当前家庭代际学习存在开放共享、基于尊重的自上而下、基于尊重的自下而上和开放非共享四种典型模式,其与家庭的构成要素,即家庭... 家庭代际学习是代际学习在家庭场域中的具体应用,它贯穿家庭的各个生命阶段,是真正意义上的终身学习实践。当前家庭代际学习存在开放共享、基于尊重的自上而下、基于尊重的自下而上和开放非共享四种典型模式,其与家庭的构成要素,即家庭结构、互动层次、学习目标与内容密切相关。从家庭结构来看,复合家庭、直系家庭、核心家庭三种家庭结构相对传统和稳定,任何家庭代际学习模式都可能发生;不完全家庭多表现为开放共享或非共享家庭代际学习模式。从互动层次来看,基于尊重的自上而下模式和基于尊重的自下而上模式均以家庭内学习为主;开放共享模式和开放非共享模式均存在个体参与形式的家庭外学习,而以家庭为单位参与的家庭外学习只发生在开放共享模式中。从学习目标与内容来看,无论哪种家庭代际学习模式,都包含知识、技能与意识提升等学习目标,以及知识传授、技能传递与意识形态建设等学习内容。家庭代际学习的有效发生受家庭凝聚力、灵活性和沟通三大因素影响。因此,推进家庭代际学习,一是要注重回归家庭深度联结,激发家庭代际学习原生动力;二是要明晰多元构成要素,选择适合的家庭代际学习模式;三是要重视有效调节机制,形成家庭学习可持续性生态。 展开更多
关键词 代际学习 家庭学习 家庭代际学习 学习模型 作用机理
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公共数据整体性治理的组织法进路——基于国家数据局的展开 被引量:1
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作者 袁周 刘苗佳 《中国科技论坛》 CSSCI 北大核心 2024年第6期111-120,共10页
当前中国公共数据治理“碎片化”特征严重,究其原因是组织之间不协同、组织职权部门化以及运作机制之间不衔接。对此,数据治理制度需进行整体性治理改革,从而提高治理效能。整体性治理改革的关键词是“整合”,而行政组织法的视角恰能为... 当前中国公共数据治理“碎片化”特征严重,究其原因是组织之间不协同、组织职权部门化以及运作机制之间不衔接。对此,数据治理制度需进行整体性治理改革,从而提高治理效能。整体性治理改革的关键词是“整合”,而行政组织法的视角恰能为其供给有力的合法性支撑,并为之提供组织整合、职权集合和机制统一的改革思路。首先,可以将国家数据局设置为数据治理的专门机关与最高机关,在组织层面上构建自上而下的、统一的数据局组织体系;其次,加强数据局的数据管理权与立法职权等,实现权力与责任的相对集中;最后,统一财政机制与人事机制,使数据治理中的技术化运作趋于一致。 展开更多
关键词 数据治理 公共数据 整体性治理 行政组织法 国家数据局
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双反射飞行时间质量分析器高分辨光电子成像谱仪研制
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作者 费泽杰 韩昌财 +7 位作者 王永天 徐辉 洪静 江一煌 周源 居鹤晨 董常武 刘洪涛 《Chinese Journal of Chemical Physics》 SCIE EI CAS CSCD 2024年第2期153-161,I0101,共10页
本文报道了一台结合电喷雾离子源和双反射飞行时间质谱的速度成像光电子能谱仪的研制过程,其可用于开展溶液中负离子的光电子能谱研究.在该装置中,电喷雾离子源产生的负离子由四极杆组成的离子引导系统传输至冷离子阱,并对负离子进行富... 本文报道了一台结合电喷雾离子源和双反射飞行时间质谱的速度成像光电子能谱仪的研制过程,其可用于开展溶液中负离子的光电子能谱研究.在该装置中,电喷雾离子源产生的负离子由四极杆组成的离子引导系统传输至冷离子阱,并对负离子进行富集和冷却,用于后端的质量选择和光电子能谱探测.该装置的关键技术之一是将双反射质量分析器与Wiley-McLaren离子加速聚焦设计进行了串联:这样可以有效地提高质谱分辨,从而准确地选择目标离子,其质量分辨率(M/△M)可达2000以上.该装置的高分辨光电子速度成像系统采用多极电子透镜设计,对于动能为0.59eV的光电子,其能谱峰的半高宽约为5.8meV,相对分辨率为~0.98%本文对该装置的工作原理,结构设计和性能测试情况进行了详细阐述。 展开更多
关键词 高分辨光电子成像 双反射飞行时间质谱 光电子能谱
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代际学习何以重塑多代工作场所:国际研究进展与思考
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作者 袁舟 李会荣 欧阳忠明 《中国职业技术教育》 北大核心 2024年第30期72-84,95,共14页
随着社会结构的变迁和劳动力老龄化的加剧,代际学习作为实践共同体和组织框架内发展起来的一个社会化过程,为多代组织减少知识流失、增强其可持续性作出了重要贡献。基于国外相关数据库的文献检索,从工作场所代际学习的概念内涵、实践... 随着社会结构的变迁和劳动力老龄化的加剧,代际学习作为实践共同体和组织框架内发展起来的一个社会化过程,为多代组织减少知识流失、增强其可持续性作出了重要贡献。基于国外相关数据库的文献检索,从工作场所代际学习的概念内涵、实践形式、影响因素、过程模型、作用效果等五个维度对相关研究成果进行系统梳理。相关研究成果呈现如下特征:一是研究视角从单一学科向多学科领域的交叉与融合;二是研究场域以教育机构、医疗机构和企业三类组织为重点;三是研究方法以实证研究为主流研究范式。未来,我国代际学习研究应当强化工作场所代际学习的理论建构,拓展工作场所代际学习的研究场域并进一步凸显工作场所代际学习的中国话语。 展开更多
关键词 工作场所 代际学习 多代劳动力 人口老龄化
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Shear strength degradation of gas hydrate-bearing sediment due to partial hydrate dissociation
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作者 yuan zhou Jiazuo zhou +1 位作者 Pan Chen Changfu Wei 《Journal of Rock Mechanics and Geotechnical Engineering》 SCIE CSCD 2024年第7期2749-2763,共15页
Extraction of methane hydrate from subseafloor reservoir may potentially trigger seabed slides and induce subsidence.To address the problems,it is crucial to properly characterize the phase equilibrium condition of po... Extraction of methane hydrate from subseafloor reservoir may potentially trigger seabed slides and induce subsidence.To address the problems,it is crucial to properly characterize the phase equilibrium condition of pore hydrate and the shear strength of the soil.As one of the key constitutive components,the phase equilibrium condition enforces a constraint over pore gas pressure,temperature and unhydrated water content.Such a constraint,however,has been traditionally ignored in analyzing the mechanical behavior of hydrate-bearing soil.In this paper,a series of stepwise hydrate dissociation tests was performed,and the phase equilibrium condition of pore hydrate was determined,providing an effective way to evaluate the unhydrated water content during hydrate dissociation.Meanwhile,a series of direct shear tests was also conducted to explore the shear strength characteristics of the soil.It is shown that the shear strength of the hydrate-bearing soil can be significantly influenced by pore gas pressure,unhydrated water content,hydrate saturation and several other factors.In particular,the measured shear strength depends upon the initial water content of the sample,pointing to a potential problem that the shear strength could be wrongly determined if not properly interpreted.A shear strength criterion,which enforces the equilibrium condition of pore hydrate,is developed for hydrate-bearing soil,establishing a link between the equilibrium condition and the shear strength.The proposed equation describes well the shear strength characteristics of hydrate-bearing soils,remarkably unifying the effects of pore pressure,temperature,water content and hydrate saturation. 展开更多
关键词 Hydrate-bearing soil Phase equilibrium condition Shear strength Unhydrated water content Mechanical behavior
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Numerical investigation of geostress influence on the grouting reinforcement effectiveness of tunnel surrounding rock mass in fault fracture zones
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作者 Xiangyu Xu Zhijun Wu +3 位作者 Lei Weng Zhaofei Chu Quansheng Liu yuan zhou 《Journal of Rock Mechanics and Geotechnical Engineering》 SCIE CSCD 2024年第1期81-101,共21页
Grouting is a widely used approach to reinforce broken surrounding rock mass during the construction of underground tunnels in fault fracture zones,and its reinforcement effectiveness is highly affected by geostress.I... Grouting is a widely used approach to reinforce broken surrounding rock mass during the construction of underground tunnels in fault fracture zones,and its reinforcement effectiveness is highly affected by geostress.In this study,a numerical manifold method(NMM)based simulator has been developed to examine the impact of geostress conditions on grouting reinforcement during tunnel excavation.To develop this simulator,a detection technique for identifying slurry migration channels and an improved fluid-solid coupling(FeS)framework,which considers the influence of fracture properties and geostress states,is developed and incorporated into a zero-thickness cohesive element(ZE)based NMM(Co-NMM)for simulating tunnel excavation.Additionally,to simulate coagulation of injected slurry,a bonding repair algorithm is further proposed based on the ZE model.To verify the accuracy of the proposed simulator,a series of simulations about slurry migration in single fractures and fracture networks are numerically reproduced,and the results align well with analytical and laboratory test results.Furthermore,these numerical results show that neglecting the influence of geostress condition can lead to a serious over-estimation of slurry migration range and reinforcement effectiveness.After validations,a series of simulations about tunnel grouting reinforcement and tunnel excavation in fault fracture zones with varying fracture densities under different geostress conditions are conducted.Based on these simula-tions,the influence of geostress conditions and the optimization of grouting schemes are discussed. 展开更多
关键词 Numerical manifold method(NMM) Grouting reinforcement Geostress condition Fault fracture zone Tunnel excavation
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Intrinsic correlation between the generalized phase equilibrium condition and mechanical behaviors in hydrate-bearing sediments
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作者 Jiazuo zhou Changfu Wei +2 位作者 Rongtao Yan yuan zhou Yi Dong 《Journal of Rock Mechanics and Geotechnical Engineering》 SCIE CSCD 2024年第7期2822-2832,共11页
The phase equilibrium and mechanical behaviors of natural gas hydrate-bearing sediment are essential for gas recovery from hydrate reservoirs.In heating closed systems,the temperature-pressure path of hydrate-bearing ... The phase equilibrium and mechanical behaviors of natural gas hydrate-bearing sediment are essential for gas recovery from hydrate reservoirs.In heating closed systems,the temperature-pressure path of hydrate-bearing sediment deviates from that of pure bulk hydrate,reflecting the porous media effect in phase equilibrium.A generalized phase equilibrium equation was established for hydrate-bearing sediments,which indicates that both capillary and osmotic pressures cause the phase equilibrium curve to shift leftward on the temperature-pressure plane.In contrast to bulk hydrate,hydrate-bearing sediment always contains a certain amount of unhydrated water,which keeps phase equilibrium with the hydrate within the hydrate stability field.With changes in temperature and pressure,a portion of pore hydrate and unhydrated water may transform into each other,affecting the shear strength of hydrate-bearing sediment.A shear strength model is proposed to consider not only hydrate saturation but also the change in temperature and pressure of hydrate-bearing sediment.The model is validated by experimental data with various hydrate saturation,temperature and pressure conditions.The deformation induced by partial dissociation was studied through depressurization tests under constant effective stress.The reduction in gas pressure within the hydrate stability field indeed caused sediment deformation.The dissociation-induced deformation can be reasonably estimated as the difference in volume between hydrate-bearing and hydrate-free sediments from the compression curves. 展开更多
关键词 Hydrate-bearing sediment Generalized phase equilibrium Unhydrated water Partial dissociation Mechanical behavior
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Genomic characterization of peritoneal lavage cytology-positive gastric cancer
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作者 zhouqiao Wu Tingfei Gu +11 位作者 Changxian Xiong Jinyao Shi Jingpu Wang Ting Guo Xiaofang Xing Fei Pang Ning He Rulin Miao Fei Shan yuan zhou Ziyu Li Jiafu Ji 《Chinese Journal of Cancer Research》 SCIE CAS CSCD 2024年第1期66-77,共12页
Objective: Positive peritoneal lavege cytology(CY1) gastric cancer is featured by dismal prognosis, with high risks of peritoneal metastasis. However, there is a lack of evidence on pathogenic mechanism and signature ... Objective: Positive peritoneal lavege cytology(CY1) gastric cancer is featured by dismal prognosis, with high risks of peritoneal metastasis. However, there is a lack of evidence on pathogenic mechanism and signature of CY1and there is a continuous debate on CY1 therapy. Therefore, exploring the mechanism of CY1 is crucial for treatment strategies and targets for CY1 gastric cancer.Methods: In order to figure out specific driver genes and marker genes of CY1 gastric cancer, and ultimately offer clues for potential marker and risk assessment of CY1, 17 cytology-positive gastric cancer patients and 31matched cytology-negative gastric cancer patients were enrolled in this study. The enrollment criteria were based on the results of diagnostic laparoscopy staging and cytology inspection of exfoliated cells. Whole exome sequencing was then performed on tumor samples to evaluate genomic characterization of cytology-positive gastric cancer.Results: Least absolute shrinkage and selection operator(LASSO) algorithm identified 43 cytology-positive marker genes, while Mut Sig CV identified 42 cytology-positive specific driver genes. CD3G and CDKL2 were both driver and marker genes of CY1. Regarding mutational signatures, driver gene mutation and tumor subclone architecture, no significant differences were observed between CY1 and negative peritoneal lavege cytology(CY0).Conclusions: There might not be distinct differences between CY1 and CY0, and CY1 might represent the progression of CY0 gastric cancer rather than constituting an independent subtype. This genomic analysis will thus provide key molecular insights into CY1, which may have a direct effect on treatment recommendations for CY1and CY0 patients, and provides opportunities for genome-guided clinical trials and drug development. 展开更多
关键词 CYTOLOGY gastric carcinoma peritoneal metastasis whole exome sequencing
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Retardation of myopia by atropine regimes
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作者 Qin Zhu Li Chen +9 位作者 Jia-Rui Liang Min Hu Li-Ping Xue Guang-Long zhou yuan zhou Jie-Ying Zhang David Fernandez-Hazoury Allison Helman Ying-Ting Zhu Xiao-Fan Zhang 《International Journal of Ophthalmology(English edition)》 SCIE CAS 2024年第11期2129-2140,共12页
Myopia is a huge health problem due to its high frequency,vision losses and public health cost.According to the World Health Organization,at least 2.2 billion people have vision impairment.Although myopia can be contr... Myopia is a huge health problem due to its high frequency,vision losses and public health cost.According to the World Health Organization,at least 2.2 billion people have vision impairment.Although myopia can be controlled at its early and middle stages,unfortunately,no cure can be achieved so far.Among the methods to control myopia,atropine,a muscarinic receptor antagonist,is the oldest but still the most effective for retardation of myopia progression.Despite such a fact,standard protocols have not been established for clinicians to use atropine for treatment of myopia.In this article,a concise and up to date summary of myopia epidemiology and pathogenesis and summarized therapeutic effects and side effects,possible mechanisms and application methods of atropine were provided in hope for clinical doctors to effectively control this problematic disease.At present,the protocol is recommend:use higher dose(1%)of atropine intermittently to effectively slowdown myopia progression in schoolchildren for 2y,and to significantly reduce side effects of atropine by decrease of atropine frequency for 1y and inhibit myopic rebound by withdrawal of topical atropine gradually for 1y.Application of a lower dose(0.05%)atropine regime should also be considered due to its effectiveness and application at regular basis. 展开更多
关键词 MYOPIA myopia progression ATROPINE SCHOOLCHILDREN
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Threshold-independent method for single-shot readout of spin qubits in semiconductor quantum dots
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作者 胡睿梓 祝圣凯 +9 位作者 张鑫 周圆 倪铭 马荣龙 罗刚 孔真真 王桂磊 曹刚 李海欧 郭国平 《Chinese Physics B》 SCIE EI CAS CSCD 2024年第1期274-279,共6页
The single-shot readout data process is essential for the realization of high-fidelity qubits and fault-tolerant quantum algorithms in semiconductor quantum dots. However, the fidelity and visibility of the readout pr... The single-shot readout data process is essential for the realization of high-fidelity qubits and fault-tolerant quantum algorithms in semiconductor quantum dots. However, the fidelity and visibility of the readout process are sensitive to the choice of the thresholds and limited by the experimental hardware. By demonstrating the linear dependence between the measured spin state probabilities and readout visibilities along with dark counts, we describe an alternative threshold-independent method for the single-shot readout of spin qubits in semiconductor quantum dots. We can obtain the extrapolated spin state probabilities of the prepared probabilities of the excited spin state through the threshold-independent method. We then analyze the corresponding errors of the method, finding that errors of the extrapolated probabilities cannot be neglected with no constraints on the readout time and threshold voltage. Therefore, by limiting the readout time and threshold voltage, we ensure the accuracy of the extrapolated probability. We then prove that the efficiency and robustness of this method are 60 times larger than those of the most commonly used method. Moreover, we discuss the influence of the electron temperature on the effective area with a fixed external magnetic field and provide a preliminary demonstration for a single-shot readout of up to 0.7K/1.5T in the future. 展开更多
关键词 quantum computation quantum dot quantum state readout
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无压烧结碳化硅超精密磨削工艺参数优化
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作者 袁舟 王宇 +2 位作者 刘淑莲 汪栋成 贾效谦 《浙江科技大学学报》 CAS 2024年第5期375-383,共9页
【目的】为降低碳化硅陶瓷材料表面粗糙度值,以优化磨削工艺参数为目标设计正交磨削试验。【方法】首先结合回归模型方差分析砂轮转速、进给速度、工件转速3个因素对磨削加工质量的影响程度;然后绘制响应曲面图,通过响应曲面图确定各参... 【目的】为降低碳化硅陶瓷材料表面粗糙度值,以优化磨削工艺参数为目标设计正交磨削试验。【方法】首先结合回归模型方差分析砂轮转速、进给速度、工件转速3个因素对磨削加工质量的影响程度;然后绘制响应曲面图,通过响应曲面图确定各参数对表面粗糙度的影响。【结果】当无压烧结碳化硅陶瓷材料用脆性去除方式时,砂轮转速对其表面粗糙度影响最大,在一定范围内砂轮转速越大,表面粗糙度值越小;求解得到最佳磨削参数组合为砂轮转速42000 r/min、进给速度1 mm/min、工件转速100 r/min,在此工艺参数下获得碳化硅陶瓷的表面粗糙度值为61.3 nm,可有效提高碳化硅陶瓷材料的加工质量。【结论】本研究结果可为降低无压烧结碳化硅陶瓷材料表面粗糙度值提供参考。 展开更多
关键词 碳化硅陶瓷 磨削 砂轮转速 表面粗糙度
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Research on the prognostic value of adjusting intraperitoneal threedimensional quality evaluation mode in laparoscopic cholecystectomy patients
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作者 yuan zhou Zhan-Qing Chen 《World Journal of Gastrointestinal Surgery》 SCIE 2024年第4期1078-1086,共9页
BACKGROUND Benign gallbladder diseases have become a high-prevalence condition not only in China but also worldwide.The main types of benign gallbladder diseases include gallbladder polyps,acute and chronic cholecysti... BACKGROUND Benign gallbladder diseases have become a high-prevalence condition not only in China but also worldwide.The main types of benign gallbladder diseases include gallbladder polyps,acute and chronic cholecystitis,and gallstones,with gallstones being the most common,accounting for over 70%of cases.Although the mortality rate of benign gallbladder diseases is low,they carry obvious potential risks.Studies have shown that an increased incidence of benign gallbladder diseases can increase the risk of cardiovascular diseases and gallbladder cancer,resulting in a substantial disease burden on patients and their families.AIM To assess the medical utility of the Configuration-Procedure-Consequence(CPC)three-dimensional quality evaluation model in modulating the prognosis of laparoscopic cholecystectomy patients.METHODS A total of 98 patients who underwent laparoscopic cholecystectomy in our hospital from February 2020 to January 2022 were selected as the subjects.According to the random number table method,they were divided into a study group and a control group,with 49 patients in each group.The control group received routine perioperative care,while the study group had the addition of the CPC three-dimensional quality evaluation.The postoperative recovery-related indicators(time to first flatus,time to oral intake,time to ambulation,hospital stay),stress indicators(cortisol and adrenaline levels),distinctions in anxiety and RESULTS The time to first flatus,time to oral intake,time to ambulation,and hospital stay of the study group patients were obviously lower than those of the control group patients,with statistical significance(P<0.05).On the 1st day after admission,there were no obvious distinctions in cortisol and adrenaline levels in blood samples,as well as in the Self-Rating Anxiety Scale(SAS)and Self-Rating Depression Scale(SDS)scores between the study group and the control group(P>0.05).However,on the 3rd day after surgery,the cortisol and adrenaline levels,as well as SAS and SDS scores of the study group patients,were obviously lower than those of the control group patients(P<0.05).The study group had 2 cases of incisional infection and 1 case of pulmonary infection,with a total incidence of complications of 6.12%(3/49),which was obviously lower than the 20.41%(10/49)in the control group(P<0.05).CONCLUSION Implementing the CPC three-dimensional quality evaluation model for patients undergoing laparoscopic cholecystectomy can help accelerate their perioperative recovery process,alleviate perioperative stress symptoms,mitigate anxiety,depression,and other adverse emotions,and to some extent,reduce the incidence of perioperative complications. 展开更多
关键词 Configuration-Procedure-Consequence Three-dimensional quality evaluation Laparoscopic Cholecystectomy Recovery process Anxiety and depression COMPLICATIONS
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改进遗传算法的电子会议汉语语音识别方法
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作者 杨艺西 武志栋 +2 位作者 袁洲 陈思平 何宇泽 《电子设计工程》 2024年第18期132-135,140,共5页
语音识别普遍存在识别不准确、不全面的问题,影响电子会议汉语记录的质量。面对这种情况,为提高语音识别性能,提出一种改进遗传算法的电子会议汉语语音识别方法。该方法通过预加重、分帧加窗以及去噪,预处理语音信号。利用改进遗传算法... 语音识别普遍存在识别不准确、不全面的问题,影响电子会议汉语记录的质量。面对这种情况,为提高语音识别性能,提出一种改进遗传算法的电子会议汉语语音识别方法。该方法通过预加重、分帧加窗以及去噪,预处理语音信号。利用改进遗传算法选取最优语音特征,语音特征包括梅尔频率倒谱系数、短时平均能量以及频谱均值。以三个特征对应数值的标准化数值为输入,利用构建的基于改进神经网络的识别模型将语音转换为对应的汉语文字,实现语音识别。结果表明,在基于改进遗传算法的识别方法应用下,误识率最高仅为2.122%,识全率最低为95.621%,由此说明所研究识别方法的识别更为准确和全面,识别效果更好。 展开更多
关键词 改进遗传算法 电子会议 特征选取 汉语语音识别
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守正创新 不断推动马克思主义军事理论中国化时代化的若干思考
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作者 袁周 李孝阳 《中共南昌市委党校学报》 2024年第4期10-14,共5页
马克思主义军事理论是马克思主义理论体系的重要组成部分。中国共产党在各个历史时期,始终重视马克思主义经典军事著作学习,重视总结历史和实践经验,不断推动马克思主义军事理论中国化时代化。习近平强军思想是当代中国的马克思主义军... 马克思主义军事理论是马克思主义理论体系的重要组成部分。中国共产党在各个历史时期,始终重视马克思主义经典军事著作学习,重视总结历史和实践经验,不断推动马克思主义军事理论中国化时代化。习近平强军思想是当代中国的马克思主义军事理论,为我们在世界百年未有之大变局、中华民族复兴之关键期、国际军事格局之大调整的背景下洞悉当代战争动因、本质及历史走向,探究现代战争制胜机理,筹划军事斗争实践,推进强军事业发展提供了根本遵循。 展开更多
关键词 马克思主义军事理论 战争本质 战争消亡 政治建军 战争制胜
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食品安全问题及其控制策略探讨
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作者 朱伟志 袁舟 +2 位作者 郑瑜颖 张旭 徐慧娜 《食品安全导刊》 2024年第12期18-20,共3页
食品安全关乎公众身体健康和食品行业的健康发展,本文分析了当前存在的食品污染、过期食品处理不到位、食品标签信息不透明等食品安全问题,并提出了加强法规和政策的制定与执行、采用先进技术提高食品安全监测和管理水平、提升消费者对... 食品安全关乎公众身体健康和食品行业的健康发展,本文分析了当前存在的食品污染、过期食品处理不到位、食品标签信息不透明等食品安全问题,并提出了加强法规和政策的制定与执行、采用先进技术提高食品安全监测和管理水平、提升消费者对食品安全的认识和自我保护能力以及构建全面而有效的食品安全管理体系等策略,旨在降低食品安全风险,提高食品安全管理效能,为食品安全提供保障。 展开更多
关键词 食品安全 食品污染 法规和政策 安全策略
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基于多相流超图神经网络的烧结矿质量预报评价系统
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作者 周元 梁其其 +1 位作者 陈果 马伟宁 《新疆钢铁》 2024年第2期61-63,共3页
“双碳”背景下,钢铁作为能耗重点行业,配矿结构亟待优化。为顺应时代洪流,本项目提出基于多相流超图神经网络的烧结矿质量预报评价系统。首先,收集烧结矿混合料化学成分、内返率等指标值。其次,使用超图学习文本数据。最后,建立烧结矿... “双碳”背景下,钢铁作为能耗重点行业,配矿结构亟待优化。为顺应时代洪流,本项目提出基于多相流超图神经网络的烧结矿质量预报评价系统。首先,收集烧结矿混合料化学成分、内返率等指标值。其次,使用超图学习文本数据。最后,建立烧结矿质量预报评价系统。该系统可应用于优化配矿,使烧结原料具有良好的制粒性能和成矿性能,实现高产、优质、低耗烧结生产。 展开更多
关键词 烧结 神经网络 多相流模型
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CO_(2)微气泡溶解动力学及提高采收率机理研究 被引量:1
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作者 贾昊卫 于海洋 +3 位作者 谢非矾 袁舟 徐克 汪洋 《力学学报》 EI CAS CSCD 北大核心 2023年第3期755-764,共10页
CO_(2)微气泡是一种具有潜力的提高采收率与碳埋存方法,本文在自主设计的CO_(2)微气泡发泡装置的基础上,表征了高温高压条件下微气泡形态,进一步研究了微气泡的溶解特征,研究结果表明:10 MPa下制备出的微气泡直径10~70μm,平均直径34.43... CO_(2)微气泡是一种具有潜力的提高采收率与碳埋存方法,本文在自主设计的CO_(2)微气泡发泡装置的基础上,表征了高温高压条件下微气泡形态,进一步研究了微气泡的溶解特征,研究结果表明:10 MPa下制备出的微气泡直径10~70μm,平均直径34.43μm;15 MPa下制备的微气泡直径更小,平均直径25.03μm;地层水高矿化度条件下,平均气泡直径277.17μm,且气泡稳定性降低.微气泡的溶解实验结果表明CO_(2)微气泡的溶解速率较高,但是未溶解的CO_(2)仍以气泡的形式在地层中运移,微气泡注入地层后将形成“碳化水+微气泡”的运移模式.采用可视化微流控平台,首次研究了高温高压条件下无化学剂辅助CO_(2)微气泡的提高采收率机理:(1)提高微观洗油效率;(2)通过体积膨胀、溶解携带作用将油滴带出盲端,采出盲端中的剩余油;(3)打破油滴的毛管压力平衡状态,采出柱状残余油;(4)在流动中产生“贾敏效应”,封堵大孔隙、提高波及效率.本文研究可为CO_(2)微气泡提高油藏采收率与碳封存提供指导. 展开更多
关键词 CO_(2)微气泡 溶解动力学 提高采收率 CO_(2)利用 微流控
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Maraviroc promotes recovery from traumatic brain injury in mice by suppression of neuroinflammation and activation of neurotoxic reactive astrocytes 被引量:10
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作者 Xi-Lei Liu Dong-Dong Sun +13 位作者 Mu-Tian Zheng Xiao-Tian Li Han-Hong Niu Lan Zhang Zi-Wei zhou Hong-Tao Rong Yi Wang Ji-Wei Wang Gui-Li Yang Xiao Liu Fang-Lian Chen yuan zhou Shu Zhang Jian-Ning Zhang 《Neural Regeneration Research》 SCIE CAS CSCD 2023年第1期141-149,共9页
Neuroinflammation and the NACHT,LRR,and PYD domains-containing protein 3 inflammasome play crucial roles in secondary tissue damage following an initial insult in patients with traumatic brain injury(TBI).Maraviroc,a ... Neuroinflammation and the NACHT,LRR,and PYD domains-containing protein 3 inflammasome play crucial roles in secondary tissue damage following an initial insult in patients with traumatic brain injury(TBI).Maraviroc,a C-C chemokine receptor type 5 antagonist,has been viewed as a new therapeutic strategy for many neuroinflammatory diseases.We studied the effect of maraviroc on TBI-induced neuroinflammation.A moderate-TBI mouse model was subjected to a controlled cortical impact device.Maraviroc or vehicle was injected intraperitoneally 1 hour after TBI and then once per day for 3 consecutive days.Western blot,immunohistochemistry,and TUNEL(terminal deoxynucleotidyl transferase-mediated dUTP nick-end labeling)analyses were performed to evaluate the molecular mechanisms of maraviroc at 3 days post-TBI.Our results suggest that maraviroc administration reduced NACHT,LRR,and PYD domains-containing protein 3 inflammasome activation,modulated microglial polarization from M1 to M2,decreased neutrophil and macrophage infiltration,and inhibited the release of inflammatory factors after TBI.Moreover,maraviroc treatment decreased the activation of neurotoxic reactive astrocytes,which,in turn,exacerbated neuronal cell death.Additionally,we confirmed the neuroprotective effect of maraviroc using the modified neurological severity score,rotarod test,Morris water maze test,and lesion volume measurements.In summary,our findings indicate that maraviroc might be a desirable pharmacotherapeutic strategy for TBI,and C-C chemokine receptor type 5 might be a promising pharmacotherapeutic target to improve recovery after TBI. 展开更多
关键词 C-C chemokine receptor type 5(CCR5)antagonist high mobility group protein B1(HMGB1) MARAVIROC M1 microglia nuclear factor-κB pathway NACHT LRR and PYD domains-containing protein 3(NLRP3)inflammasome NEUROINFLAMMATION neurological function neurotoxic reactive astrocytes traumatic brain injury
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基于图像识别与生成技术的人工智能技术应用 被引量:6
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作者 司佳 陈思平 +1 位作者 袁洲 仇亚骏 《科技资讯》 2023年第22期47-50,共4页
人工智能技术的快速发展,使其在各领域中均有广泛应用。为有效提高图像识别效率,确保在短时间内完成海量图片的信息搜索,能够运用人工智能手段完成图片内容识别与真伪识别等各项处理,学者加大了对人工智能技术在图像识别以及生成技术中... 人工智能技术的快速发展,使其在各领域中均有广泛应用。为有效提高图像识别效率,确保在短时间内完成海量图片的信息搜索,能够运用人工智能手段完成图片内容识别与真伪识别等各项处理,学者加大了对人工智能技术在图像识别以及生成技术中的应用研究力度,希望能够利用人工智能技术优势,更好地完成图像识别和生成任务,为各领域工作开展提供可靠的技术支持通过对人工智能技术应用基本情况的介绍,对基于图像识别和生成技术的人工智能技术及其应用展开深度探讨,旨在提升人工智能技术在图像识别与生成中的应用水平,推动我国图像识别与生成技术稳定性发展。 展开更多
关键词 绘画识别 笔迹识别 人工智能技术 神经网络技术 图像识别与生成技术
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