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Effect of electroacupuncture combined with rehabilitation techniques on shoulder function in patients with rotator cuff injuries
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作者 Zhi-Ying Chen Meng-Hua Wang Zhong Ye 《World Journal of Clinical Cases》 SCIE 2024年第21期4582-4589,共8页
BACKGROUND The rotator cuff is located below the acromion and deltoid muscles and comprises multiple tendons that wrap around the humeral head,maintaining shoulder joint stability.AIM To explore the effect of electroa... BACKGROUND The rotator cuff is located below the acromion and deltoid muscles and comprises multiple tendons that wrap around the humeral head,maintaining shoulder joint stability.AIM To explore the effect of electroacupuncture combined with rehabilitation techniques on shoulder function in patients with rotator cuff injuries.METHODS We selected 97 patients with rotator cuff injuries treated in the People's Hospital of Yuhuan from February 2020 to May 2023.Patients were grouped using the envelope method.RESULTS After treatment,the study group’s treatment effective rate was 94.90%(46/49 patients),significantly higher than that in the control group(79.17%,38/48 cases;P<0.05).Before treatment,there was no difference in Constant Murley Score(CMS)scores,shoulder mobility,or 36-Item Short Form Health Survey(SF-36)scale scores(P>0.05).Compared with those before treatment,the CMS scores(including pain,daily living ability,shoulder mobility,and muscle strength),all aspects of shoulder mobility(forward flexion,posterior extension,external rotation,internal rotation),and SF-36 scale scores(including physiological,psychological,emotional,physical,vitality,and health status)were higher in both groups after treatment and significantly higher in the study group(P<0.05).There was no difference in the occurrence of complications between the two treatment groups(P>0.05).CONCLUSION Electroacupuncture combined with rehabilitation techniques has a good treatment effect on patients with rotator cuff injuries,helps accelerate the recovery of shoulder function,improves the quality of life,and is highly safe. 展开更多
关键词 Electroacupuncture therapy Rehabilitation technique rotator cuff injury Shoulder joint function
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An improved computation scheme of strapdown inertial navigation system using rotation technique 被引量:8
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作者 张伦东 练军想 +1 位作者 吴美平 胡小平 《Journal of Central South University》 SCIE EI CAS 2012年第5期1258-1266,共9页
To improve the accuracy of strapdown inertial navigation system(SINS) for long term applications,the rotation technique is employed to modulate the errors of the inertial sensors into periodically varied signals,and,a... To improve the accuracy of strapdown inertial navigation system(SINS) for long term applications,the rotation technique is employed to modulate the errors of the inertial sensors into periodically varied signals,and,as a result,to suppress the divergence of SINS errors.However,the errors of rotation platform will be introduced into SINS and might affect the final navigation accuracy.Considering the disadvantages of the conventional navigation computation scheme,an improved computation scheme of the SINS using rotation technique is proposed which can reduce the effects of the rotation platform errors.And,the error characteristics of the SINS with this navigation computation scheme are analyzed.Theoretical analysis,simulations and real test results show that the proposed navigation computation scheme outperforms the conventional navigation computation scheme,meanwhile reduces the requirement to the measurement accuracy of rotation angles. 展开更多
关键词 strapdown inertial navigation system rotation technique navigation computation scheme error characteristic
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Characterization of CdZnTe crystal grown by bottom-seeded Bridgman and Bridgman accelerated crucible rotation techniques 被引量:2
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作者 王涛 介万奇 +2 位作者 徐亚东 查钢强 傅莉 《中国有色金属学会会刊:英文版》 CSCD 2009年第S3期622-625,共4页
The growth of CdZnTe crystals with diameter up to 60 mm using bottom-seeded Bridgman method as well as Bridgman accelerated crucible rotation technique (ACRT-B) was investigated. Both ingots exhibit high yields, where... The growth of CdZnTe crystals with diameter up to 60 mm using bottom-seeded Bridgman method as well as Bridgman accelerated crucible rotation technique (ACRT-B) was investigated. Both ingots exhibit high yields, where single crystal with the volume exceeding 200 cm3 is produced. The crystal properties of two ingots were compared in the aspects of yields, crystalline quality and composition uniformity. For CdZnTe ingot grown by bottom-seeded Bridgman method, the full width at half-maximum (FWHM) of X-ray rocking curve was determined to be 36″, indicating a better crystalline quality than ingot grown by ACRT-B method, which gave FWHM of 56″. The composition distribution of Zn and In in CdZnTe was determined by using electron probe microanalysis (EPMA) and inductively coupled plasma mass spectrometry (ICP-MS), respectively. The effective segregation coefficients of Zn kZn and In kIn in the two ingots were evaluated by fitting the experimental data with the Pfann equation. 展开更多
关键词 seed crystals cadmium compounds ACCELERATED CRUCIBLE rotation technique BRIDGMAN technique
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“One-man” bailout technique for high-speed rotational atherectomy——assisted percutaneous coronary intervention in an octogenarian 被引量:1
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作者 George Kassimis Dimitrios Papakonstantinou +1 位作者 Ioannis Tsounos Ioannis Kanonidis 《Journal of Geriatric Cardiology》 SCIE CAS CSCD 2020年第1期61-63,共3页
Heavily calcified coronary lesions continue to represent a challenge for percutaneous coronary intervention(PCI),as they are difficult to dilate,and it is difficult to deliver and implant drug-eluting stents(DES)prope... Heavily calcified coronary lesions continue to represent a challenge for percutaneous coronary intervention(PCI),as they are difficult to dilate,and it is difficult to deliver and implant drug-eluting stents(DES)properly.Poor stent deployment is associated with high rates of periprocedural complications and suboptimal long-term clinical outcomes.[1]Thanks to the introduction of several adjunctive PCI tools,like cutting and scoring balloons,and to the novel intravascular lithotripsy technology,the treatment of such lesions has become increasingly feasible,predictable and safe. 展开更多
关键词 Bailout procedure Calcified coronary lesion rotational atherectomy Single operator technique
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Study on the Characteristics and Efficient Cultivation Techniques of "Rice-Rice-Potato" Triple Cropping Rotation Pattern
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作者 Huang Xianliang Jiang Xianya +5 位作者 Chen Maotuo Huang Riliang Tan Zhi Wu Shangxin Lu Xixu Yang Jianyuan 《Plant Diseases and Pests》 CAS 2020年第4期28-30,35,共4页
The efficient cultivation technique of "rice-rice-potato" triple cropping rotation pattern is summarized by analyzing its characteristics and cultivation techniques in Yangjiang region of Guangdong Province,... The efficient cultivation technique of "rice-rice-potato" triple cropping rotation pattern is summarized by analyzing its characteristics and cultivation techniques in Yangjiang region of Guangdong Province,China,and machine-transplanted cultivation technique of double cropping rice and cultivation techniques of winter potato black film mulching are emphatically introduced,in order to promote the development of potato industry in Yangjiang City.The results will provide a scientific basis for the popularization and application of the "rice-rice-potato" triple cropping rotation pattern. 展开更多
关键词 RICE POTATO Triple cropping pattern rotation Cultivation technique
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Techniques and Apparatus for Measuring Rotational Core Losses of Soft Magnetic Materials
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作者 Jin-Jiang Zhong You-Guang Guo +2 位作者 Jian-Guo Zhu Hai-Yan Lu Jian-Xun Jin 《Journal of Electronic Science and Technology of China》 2007年第3期218-225,共8页
In many situations such as the cores of a rotating electrical machine and the T joints of a multiphase transformer, the local flux density varies with time in terms of both magnitude and direction, i.e. the flux densi... In many situations such as the cores of a rotating electrical machine and the T joints of a multiphase transformer, the local flux density varies with time in terms of both magnitude and direction, i.e. the flux density vector is rotating. Therefore, the magnetic properties of the core materials under the rotating flux density vector excitation should be properly measured, modeled and applied in the design and analysis of these electromagnetic devices. This paper presents an extensive review on the development of techniques and apparatus for measuring the rotational core losses of soft magnetic materials based on the experiences of various researchers in the last hundred years. 展开更多
关键词 Magnetic property measurement measuring apparatus measuring technique rotational core loss soft magnetic material.
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Enhancement of neutron irradiation uniformity for the CFBR-Ⅱ fast burst reactor with a biaxial rotational technique
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作者 梁文峰 邱东 +1 位作者 项伟灵 孙文清 《Nuclear Science and Techniques》 SCIE CAS CSCD 2015年第2期27-31,共5页
A biaxial rotational technique is proposed to improve the neutron irradiation uniformity for a large sample,and the theoretical method is established to predict and design the main parameters. The technique used a dev... A biaxial rotational technique is proposed to improve the neutron irradiation uniformity for a large sample,and the theoretical method is established to predict and design the main parameters. The technique used a device to rotate the target sample around two perpendicular axes simultaneously. Numerical calculations found that the lowest common multiple of the two angular speeds should be large enough to improve the uniformity,and the minimal experimental time should be no less than 600 s. For a three-dimensional sample with a size of 20 cm × 12 cm × 14 cm, the maximal non-uniform neutron irradiation factor of the sample is mainly determined by the distance between the center of the sample and of the point neutron source. It was computed to be less than 10% when the distance was no less than 34 cm. Experiments were carried out on the CFBR-II reactor and the experimental results were in good accordance with the theoretical analysis. As a result, the theoretical conclusions given above are reasonable and of reference value for the design of future irradiation experiments. 展开更多
关键词 照射均匀性 脉冲反应堆 中子辐照 旋转技术 双轴 实验时间 数值计算 最小公倍数
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A Study of Solar Rotation and Differential Rotation
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作者 Zhihui Zhou 《Journal of Applied Mathematics and Physics》 2023年第11期3782-3788,共7页
The Sun has solar rotation;nevertheless, many evidences have suggested that different latitude of the Sun rotates in different speed, which is now known as differential rotation. This work calculates the solar rotatio... The Sun has solar rotation;nevertheless, many evidences have suggested that different latitude of the Sun rotates in different speed, which is now known as differential rotation. This work calculates the solar rotation speeds near the equator and 30? in the northern hemisphere using Fixed-Point Arithmetic method. The calculated results show a greater speed at the equator than the speed at 30?, indicating that the speed decreases as the latitude becomes higher. . 展开更多
关键词 SUN Differential rotation Active Region fixed-point Arithmetic Method
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An Example of Multiplane Balancing Techniques in Situ
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作者 Beatriz FDe Cal Pedro Fraga 《Journal of Mechanics Engineering and Automation》 2023年第3期55-63,共9页
This paper presents the dynamic motion response by rotor unbalance malfunctions and the restraints available to oppose these applied forces and corrective techniques that can be used to reduce the effects of mass unba... This paper presents the dynamic motion response by rotor unbalance malfunctions and the restraints available to oppose these applied forces and corrective techniques that can be used to reduce the effects of mass unbalance.The mass unbalance is the most common and frequent anomaly in rotating machines,and therefore,although there are many computer programs that solve many cases,we believe it is important to remember his theory here.About this subject should techniques for correcting unbalance problems described in this document be applied.And,more importantly,a tape is made without disassembling the machine,if the transducers described in this work are installed. 展开更多
关键词 VIBRATION rotating machinery mass unbalance correction techniques.
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Use of Agroecological Techniques by Smallholder Farmers to Improve Sorghum Productivity in Burkina Faso 被引量:1
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作者 Zomboudré Georges Youma Issaka Abdoulaye +3 位作者 Batta Fatou Kaboré Roger Bourgou Tsuamba Gubbels Peter 《Journal of Agricultural Science and Technology(B)》 2018年第8期499-506,共8页
The prevailing farming system in Burkina Faso is smallholder agriculture based on cereal production, especially sorghum (Sorghum bicolor (L.) Moench) which form the staple diet for the population. Production is consta... The prevailing farming system in Burkina Faso is smallholder agriculture based on cereal production, especially sorghum (Sorghum bicolor (L.) Moench) which form the staple diet for the population. Production is constantly challenged by climate hazards, striga (Striga hermonthica (Del.) Benth.) infestation, inefficient farming practices and declining soil fertility. To address these concerns, one study on several agroecological techniques was conducted from 2013 to 2015 in a participative manner with more than 150 male and female farmers from four communities. Each farmer was asked to test out two or three agroecological techniques of his choice and to measure these new techniques against their usual farming practices. These techniques combined the use of organic fertilizer (5 t/ha) and/or mineral fertilizer (2 g/seed hole) with the systems of crop rotation and mixed cropping, in addition to the improved za? technique and the half-moon method. Plant material was composed of local landraces and improved varieties of sorghum, sesame and cowpea. On-farm application of agroecological techniques resulted in significantly increased sorghum production in all four communities. The rates of increase for grain yield were 8% for the half-moon fields and more than 130% for the rotation systems when compared to the farmers’ usual practices. More limited results were achieved with the chemical components of the soil after two years of experimentation. Only the soil’s organic matter showed improvement over the first year. This study shows that crop rotation, mixed cropping and the improved za? technique in combination with compost and improved drought-resistant varieties constitute agroecological strategies favorable to the intensification and diversification of farming systems in the studied locations. The farmers were above all impressed by the on-site management of compost by means of the za? technique which enabled large-scale fertilization of fields. 展开更多
关键词 Agroecological techniqueS SORGHUM yield COMPOST mineral FERTILIZER CROP rotation mixed CROPPING zai.
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Effects of rotation and tidal distortions on the shapes of radial velocity curves of polytropic models of pulsating variable stars
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作者 Tarun Kumar Arvind Kumar Lal Ankush Pathania 《Research in Astronomy and Astrophysics》 SCIE CAS CSCD 2018年第6期17-26,共10页
Anharmonic oscillations of rotating stars have been studied by various authors in literature to explain the observed features of certain variable stars. However, there is no study available in literature that has disc... Anharmonic oscillations of rotating stars have been studied by various authors in literature to explain the observed features of certain variable stars. However, there is no study available in literature that has discussed the combined effect of rotation and tidal distortions on the anharmonic oscillations of stars. In this paper, we have created a model to determine the effect of rotation and tidal distortions on the anharmonic radial oscillations associated with various polytropic models of pulsating variable stars. For this study we have used the theory of Rosseland to obtain the anharmonic pulsation equation for rotationally and tidally distorted polytropic models of pulsating variable stars. The main objective of this study is to investigate the effect of rotation and tidal distortions on the shapes of the radial velocity curves for rotationally and tidally distorted polytropic models of pulsating variable stars. The results of the present study show that the rotational effects cause more deviations in the shapes of radial velocity curves of pulsating variable stars as compared to tidal effects. 展开更多
关键词 stars: rotation stars: oscillations stars: binaries technique: radial velocities
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Effect of interaction of the various modes on the radial velocity curves of the polytropic models of rotationally and tidally distorted pulsating variable stars
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作者 Tarun Kumar Ankush Pathania Arvind Kumar Lal 《Research in Astronomy and Astrophysics》 SCIE CAS CSCD 2018年第12期53-66,共14页
In our previous work, we developed a model to study the effects of rotation and/or tidal distortions on anharmonic radial oscillations and hence on the radial velocity curves of the polytropic models of pulsating vari... In our previous work, we developed a model to study the effects of rotation and/or tidal distortions on anharmonic radial oscillations and hence on the radial velocity curves of the polytropic models of pulsating variable stars.We considered the first three modes(fundamental and the next two higher modes) for the polytropic models of index 1.5 and 3.0 in that work.In the present paper, we are further extending our previous work to study the effect of the interaction of various modes on anharmonic radial oscillations and hence on radial velocity curves of the rotationally and/or tidally distorted polytropic models of pulsating variable stars.For this purpose, we have considered the following cases:(i) fundamental mode(ii) fundamental and the first mode,(iii) fundamental and the next two modes and finally(iv) fundamental and the next three higher modes of pulsation in our study.The objective of this paper is also to investigate whether the interaction of various modes affects the results of our previous study or not.The results of this study show that the interaction of the fundamental mode with higher modes appreciably changes the shape of the radial velocity curve of rotationally distorted and rotationally and tidally distorted polytropic models of pulsating variable stars. 展开更多
关键词 stars:rotation stars:oscillations stars:binaries technique:radial velocities
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The effect of dimiristoylphosphatidylethanol on the rotational mobility of n-(9-Anthroyloxy) stearic acid in neuronal and model membranes
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作者 Young-Sik Park No-Soo Park +11 位作者 Jun-Bong Seo Soo-Kyoung Bae You-Kwang kim Ki-Soo Seong Young-Jun Kim Ju-Won Park Joung-Moung Shin Young-Chan Jeon In-Kyo Chung Moon-Kyoung Bae Hye-Ock Jang Il Yun 《Journal of Biophysical Chemistry》 2010年第3期133-140,共8页
The aim of this study was to provide a basis for examining the molecular mechanism for the pharmacological action of ethanol. We studied di?myristoyl?phosphatidylethanol (DMPEt)’s effects on specific locations of n-(... The aim of this study was to provide a basis for examining the molecular mechanism for the pharmacological action of ethanol. We studied di?myristoyl?phosphatidylethanol (DMPEt)’s effects on specific locations of n-(9-anthroyloxy) palmitic acid or stearic acid (n-AS) within phos?pholipids of synaptosomal plasma membrane vesicles isolated from bovine cerebral cortex (SPMV) and liposomes of total lipids (SPMVTL) and phospholipids (SPMVPL) extracted from SPMV. DMPEt increased rotational mobility (increased disordering) of hydrocarbon interior, but it decreased mobility (increased ordering) of membrane interface, in native and model membranes. The degree of rotational mobility in accordance with the carbon atom numbers of phospholipids comprising neuronal membranes was in the order at the 16, 12, 9, 6 and 2 position of aliphatic chain present in phospholipids. The sensitivity of increasing or decreasing effect of rotational mobility of hydrocarbon interior or surface region by DMPEt differed depending on the neuronal and model membranes in the descending order of SPMV, SPMVPL and SPMVTL. 展开更多
关键词 Ethanol PHOSPHATIDYLETHANOL Fluorescence QUENCHING technique rotationAL MOBILITY HYDROCARBON Interior Membranes lnterface
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mippo微创入路和后外侧入路治疗Lauge-Hansen旋后外旋Ⅲ~Ⅳ度踝关节骨折的临床疗效比较
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作者 任冬 李伟 +2 位作者 杨正刚 刘忠鑫 黄楠 《实用医院临床杂志》 2024年第3期94-97,共4页
目的对比mippo技术微创入路和后外侧入路治疗踝关Lauge-Hansen旋后外旋Ⅲ~Ⅳ度骨折的临床疗效。方法2019年1月至2022年1月我院收治的踝关节Lauge-Hansen旋后外旋Ⅲ~Ⅳ度患者60例,按照手术方法不同分为mippo技术微创入路组(A组)和后外侧... 目的对比mippo技术微创入路和后外侧入路治疗踝关Lauge-Hansen旋后外旋Ⅲ~Ⅳ度骨折的临床疗效。方法2019年1月至2022年1月我院收治的踝关节Lauge-Hansen旋后外旋Ⅲ~Ⅳ度患者60例,按照手术方法不同分为mippo技术微创入路组(A组)和后外侧入路组(B组)各30例,比较两组手术时间、透视次数、失血量、术后疼痛视觉模拟评分(VAS)、踝关节疼痛持续时间、并发症、踝关节功能、骨愈合等情况。结果两组随访时间14~24月[(22±3)月]。A组切口长度、出血量、住院时间、术后VAS评分、术后疼痛持续时间明显小于B组,术中透视次数、手术时间多于B组(P<0.05);术后3月A组患者骨折愈合优良率高于B组(P<0.05);两组患者术后6个月骨折均达骨性愈合且无畸形愈合;术后12个月两组踝关节功能优良率比较差异无统计学意义(P>0.05),但并发症率明显低于B组(P<0.05);两组均无切口感染、骨折畸形愈合、骨不连、内固定松脱等并发症发生。结论mippo技术对比后外侧入路治疗踝关节旋后外旋Ⅲ~Ⅳ度骨折均能较好恢复踝关节功能,但前者手术侵袭性更小、并发症发生率更低,疼痛持续时间更短,骨折愈合更快。 展开更多
关键词 MIPPO技术 经腓骨后外侧入路 踝关节旋后外旋型骨折
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基于总体最小二乘-旋转不变算法的地表核磁共振信号参数估计
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作者 于晓辉 冯海 +2 位作者 田宝凤 孙海欣 孙晓东 《电子与信息学报》 EI CAS CSCD 北大核心 2024年第2期720-727,共8页
在地表核磁共振(SNMR)找水系统中,根据SNMR信号的参数能够预估地下含水层的储水量、导电性以及孔隙结构等信息。然而在实际应用中探测现场采集的SNMR信号十分微弱,易受到环境噪声干扰,导致无法直接获取SNMR信号的参数。针对这一问题,该... 在地表核磁共振(SNMR)找水系统中,根据SNMR信号的参数能够预估地下含水层的储水量、导电性以及孔隙结构等信息。然而在实际应用中探测现场采集的SNMR信号十分微弱,易受到环境噪声干扰,导致无法直接获取SNMR信号的参数。针对这一问题,该文提出基于总体最小二乘-旋转不变法(TLS-ESPRIT)的地表核磁共振信号参数估计方法。基于谐波噪声与SNMR信号的相似信号特征构成一个由多个正弦衰减信号叠加的混合信号模型,使用TLS-ESPRIT将混合信号参数提取问题转换为旋转不变矩阵的广义特征值求解,从而获得SNMR信号的拉莫尔频率和弛豫时间,并结合最小二乘法求得其初始振幅和相位。仿真信号和实测信号实验结果表明此方法能够估计出混有随机噪声和工频谐波噪声的SNMR信号的参数,相比传统的谐波建模方法,在参数提取精度上效果更好。 展开更多
关键词 地表核磁共振 总体最小二乘-旋转不变法 谐波噪声
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3D-DSA与Dyna-CT在颅内支架置入术中的临床应用研究
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作者 周新华 陈良义 +1 位作者 翁磊华 吕绍茂 《中国CT和MRI杂志》 2024年第1期28-30,共3页
目的探讨三维DSA血管成像(3D-DSA)及数字平板造影机的C臂旋转并断层重建技术(DynaCT)在颅内支架置入术患者中的临床应用。方法选择2019年1月-2020年6月厦门大学附属中山医院收治92例颅内动脉狭窄患者,所有患者均行颅内支架置入术治疗,... 目的探讨三维DSA血管成像(3D-DSA)及数字平板造影机的C臂旋转并断层重建技术(DynaCT)在颅内支架置入术患者中的临床应用。方法选择2019年1月-2020年6月厦门大学附属中山医院收治92例颅内动脉狭窄患者,所有患者均行颅内支架置入术治疗,分为对照组(n=38例)和观察组(n=54例)。对照组采用3D-DSA引导,观察组采用DynaCT引导,术后进行12个月门诊随访,比较两组改良Rankin量表(mRS)评分、手术成功率、并发症、支架再狭窄及斑块检出率。结果观察组术后4个月、8个月及12个月mRS评分、支架成形术耗时低于对照组(P<0.05);观察组Dyna-CT的术前规划、观察到支架表面图像与术中所见吻合,手术成功率为83.33%,高于对照组63.16%(P<0.05);两组围术期并发症发生率无统计意义(P>0.05);观察组手术后进行12个月门诊随访,患者支架再狭窄、血管狭窄部位斑块检出率低于对照组(P<0.05)。结论DynaCT用于颅内支架置入术中能改善患者症状,缩短支架成形术耗时,有助于提高手术成功率,未增加并发症发生率,能降低血管狭窄部位斑块检出率,值得推广应用。 展开更多
关键词 三维DSA血管成像 数字平板造影 C臂旋转并断层重建技术 颅内支架置入术
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一种旋转移相式高功率微波反射阵列天线
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作者 许亮 张强 +4 位作者 袁成卫 刘金亮 孙云飞 龚鸿州 刘东琪 《强激光与粒子束》 CAS CSCD 北大核心 2024年第1期5-11,共7页
利用旋转移相技术的几何相位调控方法,提出一种基于传输相位差概念的波束扫描高功率微波反射阵列天线。电磁仿真结果表明,所设计的三叉戟形反射阵列天线单元工作于9.5~10.5 GHz,在0~40°入射角度下具有360°范围内的线性相位调... 利用旋转移相技术的几何相位调控方法,提出一种基于传输相位差概念的波束扫描高功率微波反射阵列天线。电磁仿真结果表明,所设计的三叉戟形反射阵列天线单元工作于9.5~10.5 GHz,在0~40°入射角度下具有360°范围内的线性相位调控能力,真空条件下的功率容量达到1.11 GW。采用该单元设计了半径为200 mm的圆形口径反射阵列天线,并使用全波仿真软件进行验证,利用口径相位分布的可重构特性,所设计的反射阵列天线可以实现±40°范围内的波束扫描。在10 GHz时,波束扫描过程中的增益下降小于1.7 dB,最大增益达到31.1 dBi,对应口径效率为73.42%,最低口径效率超过50%,副瓣电平和轴比始终低于-18.7 dB和1.6 dB。 展开更多
关键词 旋转移相技术 波束扫描 反射阵列天线 高功率微波 功率容量
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基于近场旋转技术的共形阵列天线方向图高效计算方法
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作者 赵黎 程友峰 +2 位作者 廖成 彭樊 丁霄 《微波学报》 CSCD 北大核心 2024年第2期14-21,34,共9页
文中提出了一种基于近场旋转技术的新型共形阵列天线方向图快速计算方法。首先,首次根据共形载体信息对单个特定天线单元近场封闭表面上的电场、磁场和采样点位置进行坐标旋转变换,进而得到其在全局坐标系下近场封闭面上的电场和磁场。... 文中提出了一种基于近场旋转技术的新型共形阵列天线方向图快速计算方法。首先,首次根据共形载体信息对单个特定天线单元近场封闭表面上的电场、磁场和采样点位置进行坐标旋转变换,进而得到其在全局坐标系下近场封闭面上的电场和磁场。然后,基于谢昆诺夫等效原理计算单个天线单元的等效电流和磁流及其所产生的辐射场,并遍历共形阵所有单元计算其在全局坐标系下的辐射场。进一步地,将全局坐标系下所有单元方向图进行矢量叠加得到共形阵列天线的远区总场。最终,通过两个具有不同载体平台与不同阵元的共形阵列天线方向图算例,并与全波仿真以及基于远场旋转技术的计算方法相比较,验证了所提出方法相较于远场旋转技术在计算精度与效率上的优势。 展开更多
关键词 共形阵列 阵列方向图计算 近场旋转技术 谢昆诺夫等效原理
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宁夏地区设施羊肚菌与麒麟瓜轮作高效栽培技术 被引量:1
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作者 朱丹 冯锐 +3 位作者 刘鹏 陈学东 张建华 周慧 《北方园艺》 CAS 北大核心 2024年第15期152-155,共4页
羊肚菌作为国际上公认的名贵珍稀食用菌,其生产周期短,经济效益高,备受食用菌产业界关注。羊肚菌与麒麟瓜轮作栽培,能够提高设施大棚利用率,降低羊肚菌连作障碍,增加农民收入。该研究总结出适宜宁夏回族自治区吴忠市红寺堡区大棚羊肚菌... 羊肚菌作为国际上公认的名贵珍稀食用菌,其生产周期短,经济效益高,备受食用菌产业界关注。羊肚菌与麒麟瓜轮作栽培,能够提高设施大棚利用率,降低羊肚菌连作障碍,增加农民收入。该研究总结出适宜宁夏回族自治区吴忠市红寺堡区大棚羊肚菌与麒麟瓜轮作的高效栽培技术,包括茬口安排、羊肚菌栽培技术要点和麒麟瓜栽培技术等。 展开更多
关键词 羊肚菌 麒麟瓜 轮作 栽培技术
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多层互剪搅拌桩工法的工艺因素模型试验研究
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作者 葛春巍 刘钟 +3 位作者 余桃喜 兰伟 杨宁晔 赵梦雅 《岩土力学》 EI CAS CSCD 北大核心 2024年第1期68-76,共9页
采用模型试验方法,对多层互剪搅拌桩工法(contra-rotational shear deep soil mixing,简称CS-DSM工法)的工艺因素进行了试验研究,探索了水泥掺量、单位桩长搅拌次数T、单位体积搅拌能量E以及内外钻杆转速比RN等工艺因素对搅拌桩均匀性... 采用模型试验方法,对多层互剪搅拌桩工法(contra-rotational shear deep soil mixing,简称CS-DSM工法)的工艺因素进行了试验研究,探索了水泥掺量、单位桩长搅拌次数T、单位体积搅拌能量E以及内外钻杆转速比RN等工艺因素对搅拌桩均匀性与强度UCS的影响。模型试验研究发现,通过多层互剪搅拌能够根除地表冒浆、防止糊钻抱钻、提高固化材料利用率。18组模型试验结果阐明搅拌桩在T-E-UCS之间存在固有关联,并揭示出机械参数、输出能量与桩身强度之间的本质关系。提供的计算方法可以定性指导选取合理的工艺参数,实现桩身设计强度目标。作为重要工艺因素,内外钻杆转速比RN与桩身强度试验曲线存在极值点,建议在工程中将1.80~2.20作为获取桩身峰值强度的最优RN值域。CS-DSM工法应用的系列研究结果为高质量搅拌桩工艺控制原则和质量保障体系提供了试验依据。 展开更多
关键词 多层互剪搅拌桩技术 搅拌次数 搅拌能量 内外钻杆转速比 CS-DSM工法
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