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Soft Base Station Technology in Wireless Communication Systems
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作者 Wang Xiyu, Guo Dandan, Cui Zhuo (Product R&D System of ZTE Corporation, Shenzhen 518004, P. R. China) 《ZTE Communications》 2010年第4期49-53,共5页
With the rapid development of wireless communications systems, different system standards are being merged. Operators take stringent measures to reduce Operational Expenditure (OPEX) and Capital Expenditure (CAPEX... With the rapid development of wireless communications systems, different system standards are being merged. Operators take stringent measures to reduce Operational Expenditure (OPEX) and Capital Expenditure (CAPEX); and as a result, soft base stations supporting multiple standards become the evolutionary tend of wireless base stations. This paper introduces the background of soft base stations and analyzes their architecture design, system modules. The key technologies in system implementation and future directions are also presented. 展开更多
关键词 wireless communications soft base station multimode base station
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Enhancing Mar and Abrasion Resistance of Acrylic Hard Coatings with Soft Base Layer
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作者 Patcharida Chouwatat Masaya Kotaki Atsushi Yokohama 《Open Journal of Organic Polymer Materials》 CAS 2016年第1期53-62,共10页
Mar and abrasion resistance were investigated by a progressive load scratch test and steel wool abrasion test, respectively. Two acrylic coating systems including trimethylolpropane triacrylate (TMPTA) and pentaerythr... Mar and abrasion resistance were investigated by a progressive load scratch test and steel wool abrasion test, respectively. Two acrylic coating systems including trimethylolpropane triacrylate (TMPTA) and pentaerythritol triacrylate (PETA) were prepared. A soft base layer was introduced as an intermediate layer between two different types of top layer and poly (methyl methacrylate) (PMMA) substrate to demonstrate the effect of soft base layer on mar and abrasion resistance. Abrasion damage on the coating surface was found to be less severe, when the soft base layer was incorporated into the coating systems. The reduction in scratch coefficient of friction (SCOF) and surface roughness was also observed. The results suggested that mar and abrasion resistance was greatly influenced by the presence of soft base layer, although different top layers were used. Moreover, it was found that abrasion resistance was further improved as the thicker soft base layer was applied. 展开更多
关键词 Acrylic Coating soft base Layer Mar Resistance Abrasion Resistance
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Soft Direct-Adaptation Based Bidirectional Turbo Equalization for MIMO Underwater Acoustic Communications 被引量:5
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作者 Junyi Xi Shefeng Yan +1 位作者 Lijun Xu Jing Tian 《China Communications》 SCIE CSCD 2017年第7期172-183,共12页
This paper proposes a soft direct-adaptation based bidirectional turbo equalizer for multiple-input multiple-output underwater acoustic communication systems. Soft, rather than hard, direct-adaptation based equalizer ... This paper proposes a soft direct-adaptation based bidirectional turbo equalizer for multiple-input multiple-output underwater acoustic communication systems. Soft, rather than hard, direct-adaptation based equalizer combined with the fast self-optimized least mean square algorithm is employed to achieve a faster convergence rate, and the second-order phase-locked loop is embedded into the equalizer to track the time-varying channel. Meanwhile, by utilizing a weighted linear combining scheme, the conventional soft direct-adaptation based equalizer is combined with the time-reversed soft direct-adaptation based equalizer to exploit bidirectional diversity and mitigate error propagation. Both the simulation and experimental results demonstrate that the soft direct-adaptation based bidirectional turbo equalizer outperforms the single-direction soft direct-adaptation based turbo equalizer, and achieves a faster convergence rate than the hard direct-adaptation based bidirectional turbo equalizer. 展开更多
关键词 soft direct-adaptation based turbo equalizer bidirectional turbo equalizer multipie-input multiple-output underwater acoustic communications
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PROJECTED GRADIENT DESCENT BASED ON SOFT THRESHOLDING IN MATRIX COMPLETION 被引量:1
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作者 Zhao Yujuan Zheng Baoyu Chen Shouning 《Journal of Electronics(China)》 2013年第6期517-524,共8页
Matrix completion is the extension of compressed sensing.In compressed sensing,we solve the underdetermined equations using sparsity prior of the unknown signals.However,in matrix completion,we solve the underdetermin... Matrix completion is the extension of compressed sensing.In compressed sensing,we solve the underdetermined equations using sparsity prior of the unknown signals.However,in matrix completion,we solve the underdetermined equations based on sparsity prior in singular values set of the unknown matrix,which also calls low-rank prior of the unknown matrix.This paper firstly introduces basic concept of matrix completion,analyses the matrix suitably used in matrix completion,and shows that such matrix should satisfy two conditions:low rank and incoherence property.Then the paper provides three reconstruction algorithms commonly used in matrix completion:singular value thresholding algorithm,singular value projection,and atomic decomposition for minimum rank approximation,puts forward their shortcoming to know the rank of original matrix.The Projected Gradient Descent based on Soft Thresholding(STPGD),proposed in this paper predicts the rank of unknown matrix using soft thresholding,and iteratives based on projected gradient descent,thus it could estimate the rank of unknown matrix exactly with low computational complexity,this is verified by numerical experiments.We also analyze the convergence and computational complexity of the STPGD algorithm,point out this algorithm is guaranteed to converge,and analyse the number of iterations needed to reach reconstruction error.Compared the computational complexity of the STPGD algorithm to other algorithms,we draw the conclusion that the STPGD algorithm not only reduces the computational complexity,but also improves the precision of the reconstruction solution. 展开更多
关键词 Matrix Completion (MC) Compressed Sensing (CS) Iterative thresholding algorithm Projected Gradient Descent based on soft Thresholding (STPGD)
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Hot-press sintering of MA Fe-based nanocrystalline/amorphous soft magnetic powder 被引量:1
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作者 卢斌 易丹青 +4 位作者 严彪 殷俊林 刘会群 吴标理 陈小丽 《中国有色金属学会会刊:英文版》 CSCD 2004年第4期686-691,共6页
Microstructures and magnetic properties of Fe84Nb7B9,Fe80Ti8B 12 and Fe32Ni36(Nb/V)7Si8B17 powders and their bulk alloys prepared by mechanical alloying(MA) method and hot-press sintering were studied. The results... Microstructures and magnetic properties of Fe84Nb7B9,Fe80Ti8B 12 and Fe32Ni36(Nb/V)7Si8B17 powders and their bulk alloys prepared by mechanical alloying(MA) method and hot-press sintering were studied. The results show that: 1) After MA for 20 h,nanocrystalline bcc singl e phase supersaturated solid solution forms in Fe84-Nb7B9 and Fe8 0Ti8B12 alloys,amorphous structure forms in Fe32Ni36Nb7 Si8B17 alloy,duplex microstructure composed of nanocrystalline γ- (FeNi) supersaturated solid solution and trace content of Fe2B phase forms in Fe32Ni36-V7Si8B17 alloy. 2) The decomposition process of supersaturated solid solution phases in Fe84Nb7B9 and Fe80Ti8B 12 alloys happens at 710780 ℃,crystallization reaction in Fe (32)Ni36Nb7Si8B17 alloy happens at 530 ℃(the temperature of peak value) and residual amorphous crystallized further happens at 760 ℃ (the temperature of peak value),phase decomposition process of supersaturated solid solution at 780 ℃ (the temperature of peak value) and crystallization reaction at 431 ℃ (the temperature of peak value) happens in Fe32Ni36V7S i8B17 alloy. 3) under 900 ℃,30 MPa,(0.5 h) hot-press sintering conditions,bulk alloys with high relative density(94.7%95.8%) can be ob tained. Except that the grain size of Fe84Nb7B9 bulk alloy is large,s uperfine grains (grain size 50200 nm) are obtained in other alloys. Exc ept that single phase microstructure is obtained in Fe80Ti8B12 bul k alloy,multi-phase microstructures are obtained in other alloys. 4) The magne tic properties of Fe80Ti8B12bulk alloy(Bs=1.74 T,Hc= 4.35 kA/m) are significantly superior to those of other bulk alloys,which is r elated to the different phases of nanocrystalline or amorphous powder formed dur ing hot-press sintering process and grain size. 展开更多
关键词 粉末冶金 软磁材料 纳米晶 机械合金化 热压烧结 磁性能
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Skin formation in drying a film of soft matter solutions:Application of solute based Lagrangian scheme
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作者 罗凌 孟凡龙 +1 位作者 张俊英 Masao Doi 《Chinese Physics B》 SCIE EI CAS CSCD 2016年第7期356-360,共5页
When a film of soft matter solutions is being dried, a skin layer often forms at its surface, which is a gel-like elastic phase made of concentrated soft matter solutions. We study the dynamics of this process by usin... When a film of soft matter solutions is being dried, a skin layer often forms at its surface, which is a gel-like elastic phase made of concentrated soft matter solutions. We study the dynamics of this process by using the solute based Lagrangian scheme which was proposed by us recently. In this scheme, the process of the gelation(i.e., the change from sol to gel) can be naturally incorporated in the diffusion equation. Effects of the elasticity of the skin phase, the evaporation rate of the solvents, and the initial concentration of the solutions are discussed. Moreover, the condition for the skin formation is provided. 展开更多
关键词 soft matter solution skin formation Onsager principle solute based Lagrangian scheme
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Covering-Based Soft Rough Sets 被引量:1
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作者 Jian-Guo Tang Kun She Yu-Qi Wang 《Journal of Electronic Science and Technology》 CAS 2011年第2期118-123,共6页
Covering-based rough sets process data organized by a covering of the universe. A soft set is a parameterized family of subsets of the universe. Both theories can deal with the uncertainties of data. Soft sets have no... Covering-based rough sets process data organized by a covering of the universe. A soft set is a parameterized family of subsets of the universe. Both theories can deal with the uncertainties of data. Soft sets have not any restrictions on the approximate description of the object,and they might form a covering of the universe. From this viewpoint,we establish a connection between these two theories. Specifically,we propose a complementary parameter for this purpose. With this parameter,the soft covering approximation space is established and the two theories are bridged. Furthermore,we study some relations between the covering and the soft covering approximation space and obtain some significant results. Finally,we define a notion of combine parameter which can help us to simplify the set of parameters and reduce the storage requirement of a soft covering approximation space. 展开更多
关键词 Complementary parameter covering-based rough sets covering-element soft set
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Applied distally based peroneus brevis muscle flaps for coverage of the soft tissue defects over the lower one-third of the leg, ankle and foot
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作者 邓国三 《外科研究与新技术》 2003年第2期128-129,共2页
Objective To investigate a simple, valuable new method for coverage of the soft tissue defect over the lower one-third of the leg, ankle and the foot. Methods The distally based peroneus brevis muscle fkps were applie... Objective To investigate a simple, valuable new method for coverage of the soft tissue defect over the lower one-third of the leg, ankle and the foot. Methods The distally based peroneus brevis muscle fkps were applied for coverage of the soft tissue defects over the lower one-third of the leg,the ankle and the foot. The muscle flaps were covered with split-thickness skin grafts. Results The distally based peroneus brevis muscle flaps were applied for coverage of the soft tissue defects over the lower one-third of the leg, the ankle and the foot in 16 cases. The larges area of the soft tissue defect was 5 cm × 7 cm. The smallest was 3 cm × 4 cm. Primary healing occured in 14 cases undergoing muscle flap construction, second-stage healing occured in 2 cases, no total flap necrosis occured in any cases. Conclusion ThisChina Medical Abstracts(Surgery) technigue is a simple and complication are lesser. The successful rates are higher. This muscle flap is suitable to the mudium or small soft tissue 展开更多
关键词 of Applied distally based peroneus brevis muscle flaps for coverage of the soft tissue defects over the lower one-third of the leg ankle and foot
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The effect of copper valence on catalytic combustion of styrene over the copper based catalysts in the absence and presence of water vapor 被引量:2
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作者 Hongyan Pan Zhiyan He +2 位作者 Qian Lin Fei Liu Zhong Li 《Chinese Journal of Chemical Engineering》 SCIE EI CAS CSCD 2016年第4期468-474,共7页
Catalysts CuOx/γ,-Al2O3-IH and CuOx/γ/-Al2O3-IM were prepared, characterized, and tested for styrene combustion in the absence and presence of water vapor. The effect of copper valence of the catalysts on the cataly... Catalysts CuOx/γ,-Al2O3-IH and CuOx/γ/-Al2O3-IM were prepared, characterized, and tested for styrene combustion in the absence and presence of water vapor. The effect of copper valence of the catalysts on the catalytic activity for styrene combustion was discussed using the theory of hard soft acids and bases (HSAB). The results showed that the existence of water vapor in feed stream inhibited the catalytic activity for styrene combustion due to the competition adsorption of water molecule. HSAB theory confirmed that the local soft acidity of the catalyst CuOx/^-AI203-1H was much stronger than that of the catalyst CuOx/^-AI203-1M because of the higher content of soft acid Cu+ on its surface, which increased the adsorption ability toward soft base of styrene and reduced the adsorption toward hard base of water vapor, and thus increased the catalytic activity for styrene combustion and weakened the negative influence of water vapor. 展开更多
关键词 Catalyst combustionStyreneCopper based catalystsWater inhibitionTheow of hard soft acids and bases
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Occlusion of the middle cerebral artery Guidance by screen imaging using an EDA-H portable medium-soft electronic endoscope 被引量:1
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作者 Xingbao Zhu Junli Luo +3 位作者 Song Liu Dongping Li Min Li Quanshui Fan 《Neural Regeneration Research》 SCIE CAS CSCD 2011年第23期1806-1809,共4页
The present study aimed to verify the practicability of performing screen-based surgical operations under the guidance of a real-time viewing and recording system (RTVRS) using a portable medium-soft electronic endo... The present study aimed to verify the practicability of performing screen-based surgical operations under the guidance of a real-time viewing and recording system (RTVRS) using a portable medium-soft electronic endoscope (pmsEE). The middle cerebral artery in rats was occluded under screen-imaging guidance using a pmsEE RTVRS to reproduce an animal model of human cerebral infarction. The screen imaging of the pmsEE RTVRS was clear, life-like, stereoscopic and synchronous with the actual operation. Screen-imaging guidance led to an accurate, smooth, minimally invasive and comparatively easy surgical procedure. The surgical success rate, time of model establishment, neurological function scores, and infarct volume were similar to those using an operating microscope. These results indicate that the self-designed pmsEE RTVRS could be utilized for portable endoscopic screen-based surgical operations. 展开更多
关键词 portable medium-soft endoscope screen-based surgical operation occlusion of middle cerebral artery cerebral infarction
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Discussion on Soft Soil Foundation Treatment Technology in Water Conservancy Construction
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作者 GUOWei 《外文科技期刊数据库(文摘版)工程技术》 2022年第6期111-114,共4页
Foundation is a key factor affecting the quality of water conservancy projects, and its stability directly affects the service life of water conservancy projects. Soft soil foundation will increase the construction di... Foundation is a key factor affecting the quality of water conservancy projects, and its stability directly affects the service life of water conservancy projects. Soft soil foundation will increase the construction difficulty of water conservancy projects and affect the stability of water conservancy projects. Therefore, the problem of soft soil foundation is a key problem to be solved in the current water conservancy construction. Based on the existing work experience, this paper explores the treatment technology of soft soil foundation in water conservancy construction from the related overview of soft soil foundation in water conservancy construction, hoping to provide a new reference perspective for the research of other scholars. 展开更多
关键词 water conservancy construction soft land base treatment technology
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Color-texture segmentation using JSEG based on Gaussian mixture modeling 被引量:4
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作者 Wang Yuzhong Yang Jie Zhou Yue 《Journal of Systems Engineering and Electronics》 SCIE EI CSCD 2006年第1期24-29,共6页
An improved approach for J-value segmentation (JSEG) is presented for unsupervised color image segmentation. Instead of color quantization algorithm, an automatic classification method based on adaptive mean shift ... An improved approach for J-value segmentation (JSEG) is presented for unsupervised color image segmentation. Instead of color quantization algorithm, an automatic classification method based on adaptive mean shift (AMS) based clustering is used for nonparametric clustering of image data set. The clustering results are used to construct Gaussian mixture modelling (GMM) of image data for the calculation of soft J value. The region growing algorithm used in JSEG is then applied in segmenting the image based on the multiscale soft J-images. Experiments show that the synergism of JSEG and the soft classification based on AMS based clustering and GMM overcomes the limitations of JSEG successfully and is more robust. 展开更多
关键词 color image segmentation JSEG adaptive mean shift based dustering Gaussian mixture modeling soft J-value.
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Effect of niobium on glass-formation ability and soft magnetic properties of Gd-doping glassy alloys 被引量:1
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作者 刘烜 丁艳红 +3 位作者 赵水生 龙毅 叶荣昌 常永勤 《Journal of Rare Earths》 SCIE EI CAS CSCD 2008年第1期89-92,共4页
The effect of niobium on glass-formation ability and soft magnetic properties were studied in Fe-Gd-B glassy alloys. The glassy alloys exhibited high glass-formation ability when the element of Nb was added. Bulk glas... The effect of niobium on glass-formation ability and soft magnetic properties were studied in Fe-Gd-B glassy alloys. The glassy alloys exhibited high glass-formation ability when the element of Nb was added. Bulk glassy rod (Fe0.87Co0.13)68.5Gd3.5Nb3B25 with a diameter up to 3 mm was produced by copper mold casting. The size of the atom might play an important role in increasing glass-formation ability. The coercive force of glassy (Fe0.87Co0.13)71.5.xGd3.sNbxB25 (x=1.2, 1.5, 2, 2.5, 3, 4) alloys decreased after the addition of niobium element and was in the range of 1.5-2.9 A/m. The permeability spectrum of (Fe0.87Co0.13)70.3Gd3.5Nb1.5B25 glassy ribbon showed that the relaxation frequency (f0) was 6.1 MHz. 展开更多
关键词 iron-based glassy alloys glass-formation ability soft magnetic properties permeability spectrum rare earths
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磷石膏对矿渣-水泥胶凝体系固化软黏土力学性能及抗渗性能的影响机制
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作者 孙涛 刘越 +2 位作者 王紫嫣 欧阳高尚 钦庭轩 《硅酸盐通报》 北大核心 2025年第12期4480-4491,共12页
软黏土含水率高、塑性大且强度极低,极易引发地基失稳和沉降等工程危害。本研究以磷石膏、矿渣和普通硅酸盐水泥复合组成的固化剂对软黏土进行了固化处理,磷石膏逐步等量替换固化剂中的惰性石粉,单变量研究了磷石膏在体系中的作用。首先... 软黏土含水率高、塑性大且强度极低,极易引发地基失稳和沉降等工程危害。本研究以磷石膏、矿渣和普通硅酸盐水泥复合组成的固化剂对软黏土进行了固化处理,磷石膏逐步等量替换固化剂中的惰性石粉,单变量研究了磷石膏在体系中的作用。首先,基于pH试验、X射线衍射试验、扫描电子显微镜试验和热重试验研究了固化土的微观结构演化从而得出固化机制。其次,通过无侧限抗压强度试验、直剪试验和渗透试验研究了固化剂中磷石膏质量占比对固化土力学性能及抗渗性能的作用规律。结果表明,固化剂的主要水化产物为水化硅(铝)酸钙(C-(A)-S-H)凝胶和钙矾石,磷石膏通过对矿粉的硫酸盐激发作用提高了固化剂的水化程度,促进了体系内钙矾石的生成,凝胶的胶结作用和钙矾石的膨胀填充作用共同提高了固化软土的力学性能和抗渗性能。随着固化剂中磷石膏质量占比逐步提升,固化土的无侧限抗压强度、抗剪强度均显著增强,最优配比条件下满足通常软土地基加固验收标准,渗透系数降低一个数量级(10^(-7)降低至10^(-8))。 展开更多
关键词 软黏土 磷石膏基土体固化剂 力学性能 抗渗性能 固化机制
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Influence of Nanocrystallization on Magnetic Properties of the Co-Based Alloys Thin Films
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作者 蒋向东 张怀武 文岐业 《Journal of Electronic Science and Technology of China》 2004年第2期60-64,共5页
The rapid recurrent thermal annealing (RRTA) method has been used to amorphous Co-Nb-Zr soft magnetic thin films fabricated by DC sputtering. By using this method, in this paper, the crystalline grains with diameter o... The rapid recurrent thermal annealing (RRTA) method has been used to amorphous Co-Nb-Zr soft magnetic thin films fabricated by DC sputtering. By using this method, in this paper, the crystalline grains with diameter of about 30~90 nm are formed and the partial nanocrystallization of the films is realized. As a result, the soft magnetic properties of the Co-based nanocrystalline thin films are improved greatly after RRTA: their resistivity is a quarter decreased; the average initial permeability is enhanced from 3 500 to over 5 000; the impedance is increased form 20 ~100 ?(at 1.4 GHz); the resonance peak is moved about 200 MHz down to low frequency. The evident improvement enables the Co-based nanocrystalline thin films to be used over a much wide frequency range of 1 KHz ~1.5 GHz. 展开更多
关键词 soft magnetic thin film Co base rapid recurrent thermal annealing NANOCRYSTALLINE
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混合教学模式联合TBL教学法在软镜验配课程中的应用 被引量:1
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作者 陈丽娟 《中国继续医学教育》 2025年第6期47-51,共5页
目的探讨混合教学模式联合任务驱动式教学法(task-based learning,TBL)在软性接触镜验配技术课程中的应用效果。方法2020年9月—2022年1月,选取漳州卫生职业学院2020级高职眼视光技术班109名学生为对照组,选取漳州卫生职业学院2021级高... 目的探讨混合教学模式联合任务驱动式教学法(task-based learning,TBL)在软性接触镜验配技术课程中的应用效果。方法2020年9月—2022年1月,选取漳州卫生职业学院2020级高职眼视光技术班109名学生为对照组,选取漳州卫生职业学院2021级高职眼视光技术班104名学生为观察组。对照组采用传统教学法,观察组采用混合教学模式联合TBL教学法。比较2组学生的期末理论考试成绩、实训成绩,问卷评价混合教学模式联合TBL教学法的效果。结果观察组的期末考试成绩为(87.44±7.59)分,高于对照组[(80.59±9.52)分],差异有统计学意义(P<0.001)。观察组学生认为该教学模式能够提升学习兴趣(94.2%),明确课程目的(88.5%),增加课堂互动(92.3%),改变学习方式(86.5%),提高自学能力(86.5%),提高主动思考能力(83.7%),提高知识应用能力(83.7%),提高分析、解决问题能力(81.7%),增强专业的热爱度和归属感(76.9%)。结论混合教学模式联合TBL教学法应用于软性接触镜验配技术课程,能有效提升学生综合素质,教学效果显著,可操作性强。 展开更多
关键词 混合教学模式 任务驱动式教学法 软性接触镜 接触镜验配 教学研究 教学质量
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强震下基础隔震结构软碰撞防护研究
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作者 金建敏 刘彦辉 +1 位作者 陈鹏 周惠蒙 《世界地震工程》 北大核心 2025年第1期165-174,共10页
针对基础隔震结构在超罕遇地震的强震作用下隔震层位移超限问题,采用已有弹性软碰撞防护装置和所研发的弹塑性软碰撞防护装置。考虑上部结构非线性,建立设置两类软碰撞防护装置的基础隔震结构模型,进行不同地震设防水准地震作用下设置... 针对基础隔震结构在超罕遇地震的强震作用下隔震层位移超限问题,采用已有弹性软碰撞防护装置和所研发的弹塑性软碰撞防护装置。考虑上部结构非线性,建立设置两类软碰撞防护装置的基础隔震结构模型,进行不同地震设防水准地震作用下设置两类软碰撞防护装置的基础隔震结构的非线性时程分析,研究不同防护距离、不同力学性能参数的弹性及弹塑性软碰撞防护装置对隔震层限位效果及上部结构地震响应的影响。结果表明:在超罕遇地震的强震作用下,两类软碰撞防护装置均可起到限制隔震层位移的作用;与仅能为隔震层附加刚度的弹性软碰撞装置相比较,能够为隔震层同时附加刚度和阻尼力的弹塑性软碰撞防护装置,隔震层限位效果和上部结构层间位移角响应控制效果均较优。合理设置弹性及弹塑性软碰撞防护装置,在将隔震层位移限制在规范限值以内的同时,上部结构最大加速度可限制在地震波输入峰值50%以下,确保基础隔震结构发挥正常的隔震功能。 展开更多
关键词 基础隔震结构 隔震层位移 软碰撞防护 限位效果 地震响应
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Le-FortⅠ型矢状前移上颌骨对骨性Ⅲ类患者鼻基底解剖形态影响的回顾性研究
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作者 吕欣 李婧怡 +3 位作者 章茜 夏成万 王育新 杨旭东 《口腔医学研究》 北大核心 2025年第8期672-678,共7页
目的:探究正颌手术中上颌骨前移距离对骨性Ⅲ类患者鼻基底区软组织形态改变的影响。方法:收集2022年2月~2024年2月于南京大学医学院附属口腔医院行Le-FortⅠ型截骨前移患者24例。收集术前1周和术后6月以上的螺旋CT影像,通过Mimics和3-Ma... 目的:探究正颌手术中上颌骨前移距离对骨性Ⅲ类患者鼻基底区软组织形态改变的影响。方法:收集2022年2月~2024年2月于南京大学医学院附属口腔医院行Le-FortⅠ型截骨前移患者24例。收集术前1周和术后6月以上的螺旋CT影像,通过Mimics和3-Matic软件进行三维重建和配准,划分出鼻旁区和鼻下区,并测量各分区软组织线距、角度、体积、曲率的变化。使用GraphPad Prism软件进行统计学分析。结果:上颌前移距离为(4.09±1.35)mm。(1)鼻旁区:鼻翼及鼻翼基底宽度分别增加(2.50±0.99)mm、(3.37±1.42)mm;右侧鼻翼及鼻翼基底突度分别增加(4.03±1.08)mm、(3.80±1.23)mm;左侧鼻翼及鼻翼基底突度分别增加(3.86±1.46)mm、(3.46±1.03)mm;左、右侧脸颊突点突度分别增加(2.41±0.97)mm、(2.28±0.93)mm;右侧鼻翼基底点-眶下点连线与冠状面夹角、鼻翼基底点-鼻下点连线与冠状面夹角、鼻翼基底点-脸颊突点连线与眶耳平面夹角分别增加(6.69±2.47)°、(7.93±15.96)°、(13.17±14.16)°;左侧鼻翼基底点-眶下点连线与冠状面夹角、鼻翼基底点-鼻下点连线与冠状面夹角、鼻翼基底点-脸颊突点连线与眶耳平面夹角分别增大(6.01±1.92)°、(6.45±15.05)°、(12.52±13.07)°;右侧、左侧鼻旁区体积增大(1289.65±538.64)mm^(3)、(1297.78±589.29)mm^(3);右侧、左侧鼻旁区曲率增大(0.08±0.05)/mm、(0.07±0.04)/mm;右侧、左侧鼻旁区曲率变化率为0.24±0.12、0.23±0.09。(2)鼻下区:鼻下长度、鼻下突度、软组织A点突度增加(0.86±0.91)mm、(2.52±1.87)mm、(3.68±1.49)mm;鼻长度减小(1.31±0.90)mm;鼻唇上角增加(4.35±2.19)°,面突角减小(9.26±4.35)°;鼻下区体积增加(1933.00±740.30)mm^(3);鼻下区曲率增大(0.11±0.09)/mm,变化率为0.38±0.20。结论:上颌前移术后,鼻翼增大、鼻长度减小、鼻下长度增加、软组织突出度增大;鼻旁区及鼻下区曲率变化率分别维持在0.2~0.3和0.4,前移术式可有效改善鼻基底凹陷。 展开更多
关键词 正颌手术 鼻基底 软组织形态
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高性能铁基非晶/纳米晶合金软磁性能研究进展 被引量:1
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作者 于长江 刘文峰 +3 位作者 李晓雪 陈峰华 张克维 张敏刚 《磁性材料及器件》 2025年第1期65-71,共7页
综合介绍了铁基非晶/纳米晶合金软磁性能的研究进展,结合铁基非晶/纳米晶合金的发展历程,阐述了元素调控和不同处理工艺对铁基非晶/纳米晶合金软磁性能的影响。其中,磁性元素含量的增加可直接提高合金的饱和磁感应强度;类金属元素的存... 综合介绍了铁基非晶/纳米晶合金软磁性能的研究进展,结合铁基非晶/纳米晶合金的发展历程,阐述了元素调控和不同处理工艺对铁基非晶/纳米晶合金软磁性能的影响。其中,磁性元素含量的增加可直接提高合金的饱和磁感应强度;类金属元素的存在提高了合金的非晶形成能力,保证了合金的非晶态结构;过渡族元素的添加可抑制热处理过程中产生的纳米晶粒的长大,进一步提高了合金的软磁性能。为进一步设计开发软磁性能优异的铁基非晶/纳米晶合金提供参考。 展开更多
关键词 软磁材料 铁基非晶合金 纳米晶合金 饱和磁感应强度 矫顽力
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基于CaO绝缘层和Fe_(x)O_(y)中间层的铁基软磁复合材料的制备与性能优化
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作者 何豪 李凯旋 +3 位作者 刘洋 吴朝阳 黄贞益 王锐 《粉末冶金技术》 北大核心 2025年第5期537-547,共11页
为了探索CaO作为绝缘层在软磁复合材料中的应用潜力,提出了在CaO绝缘层和铁基体之间引入Fe_(x)O_(y)作为中间过渡层的策略,以缓解铁粉基体与CaO绝缘层之间的晶格失配和裂纹形成。以还原铁粉为研究对象,采用表面氧化、水热合成以及(CH_(3... 为了探索CaO作为绝缘层在软磁复合材料中的应用潜力,提出了在CaO绝缘层和铁基体之间引入Fe_(x)O_(y)作为中间过渡层的策略,以缓解铁粉基体与CaO绝缘层之间的晶格失配和裂纹形成。以还原铁粉为研究对象,采用表面氧化、水热合成以及(CH_(3)COO)_(2)Ca热分解结合冷压成形的工艺,成功制备了具有优异软磁性能的Fe/Fe_(x)O_(y)/CaO软磁复合材料。深入研究了CaO绝缘层的形成机理,进一步探讨了乙酸钙添加量对Fe/Fe_(x)O_(y)/CaO软磁复合材料结构和电磁性能的影响。结果发现,Fe_(x)O_(y)中间层的引入有效缓解了铁粉基体与CaO绝缘层之间的晶格失配,显著减少了裂纹形成。同时,CaO绝缘层有效提高了材料的电阻率,减少了涡流损耗,从而实现了更低的磁损耗和更高的磁导率。通过精确控制乙酸钙的添加量,可以进一步优化Fe/Fe_(x)O_(y)/CaO软磁复合材料的磁性能和电性能,达到减少能量损耗的目的。 展开更多
关键词 铁基软磁复合材料 CaO绝缘层 中间过渡层 晶格失配 磁性能
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