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A processing technique for accurate target angle estimation using wideband monopulse radars
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作者 CHEN Chengzeng LIU Dan +1 位作者 XU Xiaojian LU Yaobing 《Journal of Systems Engineering and Electronics》 2025年第2期370-379,共10页
Accurate target angle estimation is one of the chal-lenges for wideband radars due to the fact that target occupies multiple range bins,resulting in lower energy or signal to noise ratio in a single range bin.This pap... Accurate target angle estimation is one of the chal-lenges for wideband radars due to the fact that target occupies multiple range bins,resulting in lower energy or signal to noise ratio in a single range bin.This paper proposes a processing technique for enhanced accuracy of target angle estimates for wideband monopulse radars.Firstly,to accumulate the energy of the received echo signals from different scatterers on a target,the phase difference between different scatterers on a target is estimated using the minimum entropy phase estimation method combining with the correlation between adjacent pulses.Then,the monopulse ratio is obtained by using the signals from the accumulated sum and difference channels.The target angle is estimated by weighting the accumulated echo energy for accu-racy enhancement.Experimental results based on both numeri-cal simulation and measured data are presented to validate the effectiveness of the proposed technique. 展开更多
关键词 wideband radar target angle estimation adjacent pulses correlation.
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Fixed-time cooperative interception guidance law with angle constraints for multiple flight vehicles
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作者 ZHAO Enjiao DING Xue +1 位作者 ZHANG Ke YUAN Zengyu 《Journal of Systems Engineering and Electronics》 2025年第2期569-579,共11页
This paper presents a fixed-time cooperative gui-dance method with impact angle constraints for multiple flight vehicles (MFV) to address the challenges of intercepting large maneuvering targets with difficulty and lo... This paper presents a fixed-time cooperative gui-dance method with impact angle constraints for multiple flight vehicles (MFV) to address the challenges of intercepting large maneuvering targets with difficulty and low precision. A coopera-tive guidance model is proposed, transforming the cooperative interception problem into a consensus problem based on the remaining flight time of the flight vehicles. First, the impact angle constraint is converted into the line of sight (LOS) angle con-straint, and a new fixed-time convergent non-singular terminal sliding surface is introduced, which resolves the singularity issue of the traditional sliding surfaces. With this approach, LOS angle rate and normal overloads can converge in fixed time, ensuring that the upper bound of the system convergence time is not affected by the initial value of the system. Furthermore, the maneuvering movement of the target is considered as a system disturbance, and an extended state observer is employed to estimate and compensate for it in the guidance law. Lastly, by applying consensus theory and distributed communication topology, the remaining flight time of each flight vehicle is syn-chronized to ensure that they intercept the target simulta-neously with different impact angles. Simulation experiments are conducted to validate the effectiveness of the proposed cooper-ative interception and guidance method. 展开更多
关键词 fixed-time control communication topology con-sensus theory impact angle cooperative guidance
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Strength and failure characteristics of hard rock containing a single structural plane under varied loading angles : A true triaxial investigation
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作者 XU Huai-sheng LI Shao-jun +3 位作者 XU Ding-ping LIU Xu-feng FENG Guang-liang WANG Zhao-feng 《Journal of Central South University》 2025年第5期1903-1921,共19页
The spatial relationship between structural planes and principal stresses significantly affects the mechanical properties of deep hard rock.This paper examines the effect of the loading angle under true triaxial compr... The spatial relationship between structural planes and principal stresses significantly affects the mechanical properties of deep hard rock.This paper examines the effect of the loading angle under true triaxial compression.While previous studies focused on the angleβbetween the maximum principal stress and the structural plane,the role of angleω,between the intermediate principal stress and the structural plane,is often overlooked.Utilizing artificially prefabricated granite specimens with a single non-penetrating structural plane,we set the loading angleβto range from 0°to 90°across seven groups,and assignedωvalues of 0°and 90°in two separate groups.The results show that the peak strength is negatively correlated withβup to 45°,beyond which it tends to stabilize.The angleωexerts a strengthening effect on the peak strength.Deformation mainly occurs post-peak,with the strain values ε_(1) and ε_(3) reaching levels 2−3 times higher than those in intact rock.The structural plane significantly influences failure mode whenω=0°,while failure localizes near the σ_(3) surface of the specimens whenω=90°.The findings enhance data on structural plane rocks under triaxial compression and inform theoretical research,excavation,and support design of rock structures. 展开更多
关键词 true triaxial compression hard rock structural plane loading angle STRENGTH failure characteristics
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Failure behavior of rock and steel slag cemented paste backfill composite structures under uniaxial compression:Effects of interface angle and steel slag content
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作者 HAO Jian-shuai ZHOU Zi-han +1 位作者 CHEN Zhong-hui CHE Zeng-hui 《Journal of Central South University》 2025年第7期2679-2695,共17页
The stability of the“surrounding rock-backfill”com posite system is crucial for the safety of mining stopes.This study systematically investigates the effects of steel slag(SS)content and interface angle on the stre... The stability of the“surrounding rock-backfill”com posite system is crucial for the safety of mining stopes.This study systematically investigates the effects of steel slag(SS)content and interface angle on the strength and failure characteristics of rock and SS-cemented paste backfill composite specimens(RBCS)through uniaxial compression strength tests(UCS),acoustic emission systems(AE),and 3 D digital image correlation monitoring technology(3 D-DIC).The intrinsic mechanism by which SS content influences the strength of SS-CPB was revealed through an analysis of its hydration reaction degree and microstructural characteristics under varying SS content.Moreover,a theoretical strength model incorporating different interface angles was developed to explore the impact of interface inclination on failure modes and mechanical strength.The main conclusions are as follows:The incorporation of SS enhances the plastic characteristics of RBCS and reduces its brittleness,with the increase of SS content,the stress-strain curve of RBCS in the“staircase-like”stag e becomes smoother;When the interface angle is 45°,the RBCS stress-strain curve exhibits a bimodal feature,and the failure mode changes from Y-shaped fractures to interface and axial splitting;The addition of SS results in a reduction of hydration products such as Ca(OH)_(2) in the backfill cementing system and an increase in harmful pores,which weakens the bonding performance and strength of RBCS,and the SS content should not exceed 45%;As the interface angle increases,the strength of RBCS decreases,and the critical interface slip angle decreases first and then increases with the increase in the E S/E R ratio.This study provides technical references for the large-scale application of SS in mine backfill. 展开更多
关键词 steel slag-cemented paste backfill interface angle rock-backfill composite structures failure mode
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Exploring the effects of angle of incidence on stabbing resistance in advanced protective textiles:Novel experimental framework and analysis
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作者 Mulat Alubel Abtew François Boussu Irina Cristian 《Defence Technology(防务技术)》 2025年第2期67-82,共16页
Despite numerous research investigations to understand the influences of various structural parameters,to the authors'knowledge,no research has been the effect of different angles of incidence on stab response and... Despite numerous research investigations to understand the influences of various structural parameters,to the authors'knowledge,no research has been the effect of different angles of incidence on stab response and performance of different types of protective textiles.Three distinct structures of 3D woven textiles and 2D plain weave fabric made with similar high-performance fiber and areal density were designed and manufactured to be tested.Two samples,one composed of a single and the other of 4-panel layers,from each fabric type structure,were prepared,and tested against stabbing at[0○],[22.5○],and[45○]angle of incidence.A new stabbing experimental setup that entertained testing of the specimens at various angles of incidence was engineered and utilized.The stabbing bench is also equipped with magnetic sensors and a UK Home Office Scientific Development Branch(HOSDB)/P1/B sharpness engineered knives to measure the impact velocity and exerted impact energy respectively.A silicon compound was utilized to imprint the Back Face Signature(BFS)on the backing material after every specimen test.Each silicon print was then scanned,digitized,and precisely measured to evaluate the stab response and performance of the specimen based on different performance variables,including Depth of Trauma(DOT),Depth of Penetration(DOP),and Length of Penetration(LOP).Besides,the post-impact surface failure modes of the fabrics were also measured using Image software and analyzed at the microscale level.The results show stab angle of incidence greatly influences the stab response and performance of protective textiles.The outcome of the study could provide not only valuable insights into understanding the stab response and capabilities of protective textiles under different angle of incidence,but also provide valuable information for protective textile manufacturer,armor developer and stab testing and standardizing organizations to consider the angle of incidence while developing,testing,optimizing,and using protective textiles in various applications. 展开更多
关键词 2D/3D woven fabrics Impact protective fabric Drop tower perforation test Stab resistance testing protocol angle of incidence Multi-layer panels Soft body armor Impact surface damage
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Closed-form guidance law for velocity maximization with impact angle constraint
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作者 ZHANG Jiahui WEN Qiuqiu 《Journal of Systems Engineering and Electronics》 SCIE CSCD 2024年第5期1295-1303,共9页
Final velocity and impact angle are critical to missile guidance.Computationally efficient guidance law with compre-hensive consideration of the two performance merits is challeng-ing yet remains less addressed.Theref... Final velocity and impact angle are critical to missile guidance.Computationally efficient guidance law with compre-hensive consideration of the two performance merits is challeng-ing yet remains less addressed.Therefore,this paper seeks to solve a type of optimal control problem that maximizes final velocity subject to equality point constraint of impact angle con-straint.It is proved that the crude problem of maximizing final velocity is equivalent to minimizing a quadratic-form cost of cur-vature.The closed-form guidance law is henceforth derived using optimal control theory.The derived analytical guidance law coincides with the widely-used optimal guidance law with impact angle constraint(OGL-IAC)with a set of navigation parameters of two and six.On this basis,the optimal emission angle is determined to further increase the final velocity.The derived optimal value depends solely on the initial line-of-sight angle and impact angle constraint,and thus practical for real-world appli-cations.The proposed guidance law is validated by numerical simulation.The results show that the OGL-IAC is superior to the benchmark guidance laws both in terms of final velocity and missing distance. 展开更多
关键词 MISSILE guidance law proportional-navigation guidance impact angle
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On the effect of pitch and yaw angles in oblique impacts of smallcaliber projectiles
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作者 Teresa Fras 《Defence Technology(防务技术)》 SCIE EI CAS CSCD 2024年第1期73-94,共22页
A terminal ballistic analysis of the effects of 7.62 mm × 51 AP P80 rounds on inclined high-strength armor steel plates is the focus of the presented study.The findings of an instrumented ballistic testing combin... A terminal ballistic analysis of the effects of 7.62 mm × 51 AP P80 rounds on inclined high-strength armor steel plates is the focus of the presented study.The findings of an instrumented ballistic testing combined with 3D advanced numerical simulations performed using the IMPETUS Afea? software yielded the conclusions.The experimental verification proved that slight differences in the pitch-andyaw angles of a projectile upon an impact caused different damage types to the projectile’s core.The residual velocities predicted numerically were close to the experimental values and the calculated core deviations were in satisfactory agreement with the experimental results.An extended matrix of the core deviation angles with combinations of pitch-and-yaw upon impact angles was subsequently built on the basis of the numerical study.The presented experimental and numerical investigation examined thoroughly the influence of the initial pitch and yaw angles on the after-perforation projectile’s performance. 展开更多
关键词 Ballistic impact Small-caliber projectile Pitch and yaw impact angles SHADOWGRAPHY IMPETUS Afea Numerical simulations
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Visual navigation in orchard based on multiple images at different shooting angles
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作者 MA Zenghong YUE Jiawen +3 位作者 YIN Cheng ZHAO Runmao CHANDA Mulongoti DU Xiaoqiang 《智能化农业装备学报(中英文)》 2024年第4期51-65,共15页
The orchards usually have rough terrain,dense tree canopy and weeds.It is hard to use GNSS for autonomous navigation in orchard due to signal occlusion,multipath effect,and radio frequency interference.To achieve auto... The orchards usually have rough terrain,dense tree canopy and weeds.It is hard to use GNSS for autonomous navigation in orchard due to signal occlusion,multipath effect,and radio frequency interference.To achieve autonomous navigation in orchard,a visual navigation method based on multiple images at different shooting angles is proposed in this paper.A dynamic image capturing device is designed for camera installation and multiple images can be shot at different angles.Firstly,the obtained orchard images are classified into sky and soil detection stage.Each image is transformed to HSV space and initially segmented into sky,canopy and soil regions by median filtering and morphological processing.Secondly,the sky and soil regions are extracted by the maximum connected region algorithm,and the region edges are detected and filtered by the Canny operator.Thirdly,the navigation line in the current frame is extracted by fitting the region coordinate points.Then the dynamic weighted filtering algorithm is used to extract the navigation line for the soil and sky detection stage,respectively,and the navigation line for the sky detection stage is mirrored to the soil region.Finally,the Kalman filter algorithm is used to fuse and extract the final navigation path.The test results on 200 images show that the accuracy of visual navigation path fitting is 95.5%,and single frame image processing costs 60 ms,which meets the real-time and robustness requirements of navigation.The visual navigation experiments in Camellia oleifera orchard show that when the driving speed is 0.6 m/s,the maximum tracking offset of visual navigation in weed-free and weedy environments is 0.14 m and 0.24 m,respectively,and the RMSE is 30 mm and 55 mm,respectively. 展开更多
关键词 ORCHARD visual navigation multiple shooting angles region segmentation Kalman filter
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AngleⅢ患者上颌前牵引矫治时机的初步探讨 被引量:32
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作者 范建谊 叶湘玉 +3 位作者 周洪 陈曦 王爽 陈挺 《实用口腔医学杂志》 CAS CSCD 北大核心 2002年第3期244-247,共4页
目的 :初步探讨前牵引矫治器对生长发育期Ⅲ类错牙合上颌发育不足患者的矫治时机。方法 :选取 2 0例研究对象 ,分成两组 ,即大年龄组 (9~ 12岁 )和小年龄组 (5~ 8岁 ) ,采用前牵引矫治器进行治疗 ,拍摄治疗前后的头颅定位侧位片并进行... 目的 :初步探讨前牵引矫治器对生长发育期Ⅲ类错牙合上颌发育不足患者的矫治时机。方法 :选取 2 0例研究对象 ,分成两组 ,即大年龄组 (9~ 12岁 )和小年龄组 (5~ 8岁 ) ,采用前牵引矫治器进行治疗 ,拍摄治疗前后的头颅定位侧位片并进行X线头影测量分析。结果 :上颌前牵引对两组患者均产生了良好的矫治效果 :上颌骨前移 ,下颌骨后旋 ,前牙反牙合纠正 ,磨牙关系达到中性 ;两组对比显示小年龄患者的前牵引治疗具有更短的治疗时间、更多的骨骼改变、更少的牙齿改变以及更少的副作用等优点。结论 展开更多
关键词 angle 上颌前牵引 矫治 安氏Ⅲ类错He 口腔正畸
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AngleⅡ~1错骨性特点研究 被引量:18
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作者 曹军 段银钟 林珠 《实用口腔医学杂志》 CAS CSCD 北大核心 2002年第6期532-535,共4页
目的 :研究AngleⅡ1 错牙合患者颌面硬组织特征 ,找出适合这一特征的合理对症治疗方法。方法 :利用头颅侧位定位X线片 ,通过正常牙合者与AngleⅡ1 错牙合患者 13项分析指标的比较研究 ,找出AngleⅡ1 患者的骨性变异特征。结果 :在矢状... 目的 :研究AngleⅡ1 错牙合患者颌面硬组织特征 ,找出适合这一特征的合理对症治疗方法。方法 :利用头颅侧位定位X线片 ,通过正常牙合者与AngleⅡ1 错牙合患者 13项分析指标的比较研究 ,找出AngleⅡ1 患者的骨性变异特征。结果 :在矢状骨性关系方面 ,AngleⅡ1 错牙合组较正常牙合组SNB角、SL距明显减小 ,ANB角显明增大、而SNA角及PNS ANS距无明显差异 ;在骨性垂直关系方面 ,AngleⅡ1 错牙合组较正常牙合组UM PP距及LM MP距均明显减小 ,UI PP距明显增大 ,而LI PP距没有明显差异 ;在下颌骨生长方向方面SN MP角均明显减少。结论 :该类畸形具有后部牙槽高度不足 ,下颌后缩及下颌骨的逆时针旋转生长倾向。提示此类患者的治疗适于采取能使下颌向前、下移位的方法 。 展开更多
关键词 angleⅡ^1错He 骨性机制 测颅法 口腔正畸
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下颌前伸矫治器和Herbst矫治器治疗AngleⅡ类错的对比研究 被引量:8
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作者 陈国新 贺红 +2 位作者 王彤 张漫 华先明 《口腔医学研究》 CAS CSCD 2003年第6期510-511,共2页
目的 :比较下颌前伸矫治器 (MandibularProtractionAppliance ,MPA)和Herbst矫治器对AngleⅡ类错牙合的治疗效果。方法 :选择 2 6例AngleⅡ类错牙合病人 ,男 14例 ,女 12例 ,最大 13岁 ,最小 10岁。X线头影测量显示主要为下颌后缩及轻... 目的 :比较下颌前伸矫治器 (MandibularProtractionAppliance ,MPA)和Herbst矫治器对AngleⅡ类错牙合的治疗效果。方法 :选择 2 6例AngleⅡ类错牙合病人 ,男 14例 ,女 12例 ,最大 13岁 ,最小 10岁。X线头影测量显示主要为下颌后缩及轻微上颌前突 ,手腕片显示为生长发育高峰期。将这些病人分成两组 ,一组用下颌前伸矫治器治疗 (MPA组 ) ,另一组用Herbst矫治器进行治疗 (HA组 )。功能矫治结束时 ,两组病例均摄X线头颅定位侧位片 ,由专人定点、测量 ,并进行统计学分析。结果 :X线头影测量结果显示两组病例中Co -Pg、Go -Pg及Co -Go均增大 ,其变化量经统计学检验差异无显著性意义 ,表明下颌前伸矫治器及Herbst矫治器均能促进下颌骨生长 ,尤其是下颌升支的生长 ;SNB、ANB、U1-L1、U1-NL及L1-MP的变化量经过统计学检验差异有显著性意义 ,说明下颌前伸矫治器和Herbst矫治器都能有效矫治AngleⅡ类错牙合颌骨矢状关系不调 ,尤其是前者更有效 ,而Herbst矫治器易引起支抗丢失 ,即易使上颌前牙舌向倾斜、下颌前牙唇倾。结论 :下颌前伸矫治器和Herbst矫治器治疗早期AngleⅡ类错牙合均可取得明显的骨胳改变 。 展开更多
关键词 下颌前伸矫治器 HERBST矫治器 治疗 angleⅡ类错He X线头影测量
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生物调节器矫治AngleⅢ 类错对咀嚼效能的影响 被引量:4
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作者 毛靖 赵宏 周继红 《华中科技大学学报(医学版)》 CAS CSCD 北大核心 2002年第3期326-328,共3页
采用生物调节器 (BIONATOR)矫治 Angle 类错牙合 ,研究矫治前后对其咀嚼效能的影响。对 15例替牙晚期、恒牙初期的 Angle 类错牙合采用 BIONATOR矫治 ,并进行矫治前后的比较分析。BIONATOR矫治 Angle 类错牙合能够显著提高咀嚼效能 ,结... 采用生物调节器 (BIONATOR)矫治 Angle 类错牙合 ,研究矫治前后对其咀嚼效能的影响。对 15例替牙晚期、恒牙初期的 Angle 类错牙合采用 BIONATOR矫治 ,并进行矫治前后的比较分析。BIONATOR矫治 Angle 类错牙合能够显著提高咀嚼效能 ,结果提示 :采用 展开更多
关键词 生物调节器 矫治 angleⅢ类错He 咀嚼效能
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成人Angle Ⅱ~2错畸形患者髁突位置及颞下颌关节形态的CBCT观察研究 被引量:11
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作者 李帅 林薇薇 +1 位作者 陈金武 丁寅 《实用口腔医学杂志》 CAS CSCD 北大核心 2013年第3期389-393,共5页
目的:利用锥形束CT(CBCT)评估成人Angle Ⅰ与Angle Ⅱ2错畸形患者颞下颌关节的形态特征及与颞下颌关节窝的关系。方法:通过对30例Angle Ⅰ与30例Angle Ⅱ2类错畸形成人患者行TMJ的CBCT扫描,在GALILEOS工作站分析测量颞下颌关节窝间... 目的:利用锥形束CT(CBCT)评估成人Angle Ⅰ与Angle Ⅱ2错畸形患者颞下颌关节的形态特征及与颞下颌关节窝的关系。方法:通过对30例Angle Ⅰ与30例Angle Ⅱ2类错畸形成人患者行TMJ的CBCT扫描,在GALILEOS工作站分析测量颞下颌关节窝间隙、髁突相关指标,进行统计学分析,比较Angle Ⅰ与Angle Ⅱ2TMJ形态学之间的差异。结果:①Angle Ⅰ、An-gle Ⅱ2类左右两侧髁突在各自颞下颌关节窝内的位置均无明显差异(P>0.05)。②Angle Ⅱ2组颞下颌关节窝深度、前间隙、上间隙均大于Angle Ⅰ组,后间隙小于Angle Ⅰ组(P<0.05)。结论:Angle Ⅰ与Angle Ⅱ2患者两侧髁突在颞下颌关节窝内位置对称,Angle Ⅱ2颞下颌关节窝深度,上间隙及前间隙比Angle Ⅰ大,后间隙比Angle Ⅰ小。 展开更多
关键词 angleⅡ2类错[牙合]畸形 颞下颌关节 锥形束CT(CBCT)
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Angle Ⅲ类错的矫治 被引量:10
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作者 牛百平 叶湘玉 《实用口腔医学杂志》 CAS CSCD 北大核心 1998年第4期308-310,共3页
AngleⅢ类错牙合畸形是临床上常见的错牙合畸形之一。此类畸形严重影响患者的容貌,咀嚼、发音及心理健康状况。由于其发病因素较为复杂,畸形表现出不同的类型。因此对Ⅲ类错牙合的正确诊断是治疗成功的基础。本文从Ⅲ类错牙合的... AngleⅢ类错牙合畸形是临床上常见的错牙合畸形之一。此类畸形严重影响患者的容貌,咀嚼、发音及心理健康状况。由于其发病因素较为复杂,畸形表现出不同的类型。因此对Ⅲ类错牙合的正确诊断是治疗成功的基础。本文从Ⅲ类错牙合的诊断与鉴别诊断以及不同生长发育时期... 展开更多
关键词 错HE 矫治 angleⅢ类 诊断 治疗
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骨性AngleⅡ类2分类错正畸治疗前后硬组织的变化 被引量:7
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作者 陈国新 陈香 +3 位作者 贺红 熊晖 华先明 蔡萍 《口腔医学研究》 CAS CSCD 2005年第3期316-318,共3页
目的:采用直丝弓矫治器矫治成年患者骨性AngleⅡ类2分类错he,以研究正畸治疗前后牙、颌硬组织变化,评价正畸矫治效果。方法:本文选择了8例AngleⅡ类2分类错he成年患者,男3例,女5例,年龄19~27岁,平均23.6岁。拔除双侧上颌第一... 目的:采用直丝弓矫治器矫治成年患者骨性AngleⅡ类2分类错he,以研究正畸治疗前后牙、颌硬组织变化,评价正畸矫治效果。方法:本文选择了8例AngleⅡ类2分类错he成年患者,男3例,女5例,年龄19~27岁,平均23.6岁。拔除双侧上颌第一双尖牙,运用直丝弓矫治器进行治疗,拍摄治疗前后X线头颅定位侧位片,进行治疗前后的X线头影测量研究。结果:治疗后SNA角减小,ANB角减小,U1-SN角增大,L1-MP角增大,U1-L1角减小。上颌切牙牙根及上颌基骨明显腭向移动,减小了上颌骨突度;下颌切牙牙冠明显唇向倾斜,代偿了下颌骨后缩。结论:骨性AngleⅡ类2分类错he患者经过上颌拔牙矫治后,面形有所改善,取得了理想的矫治效果。 展开更多
关键词 直丝弓矫治器 angleⅡ类2分类错he 头影测量
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Herbst矫治器治疗AngleⅡ类错的临床应用研究 被引量:3
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作者 王彤 程祥荣 +1 位作者 沈真祥 贺红 《口腔医学研究》 CAS CSCD 2003年第6期499-502,共4页
目的 :观察Herbst矫治器对生长期AngleⅡ类错牙合患者牙牙合、颅面产生的影响。方法 :选取 16例青春生长期的安氏Ⅱ类错牙合患者采用全牙弓整体支抗的带环式Herbst矫治器进行治疗 ,通过治疗前后的头影测量片对比 ,分析该矫治器的疗效。... 目的 :观察Herbst矫治器对生长期AngleⅡ类错牙合患者牙牙合、颅面产生的影响。方法 :选取 16例青春生长期的安氏Ⅱ类错牙合患者采用全牙弓整体支抗的带环式Herbst矫治器进行治疗 ,通过治疗前后的头影测量片对比 ,分析该矫治器的疗效。结果 :1)所有患者面型均改善 ,磨牙关系均达Ⅰ类或接近Ⅲ类 ,覆盖和覆牙合明显减小。 2 )矢状方向上 ,SNB增加 ,ANB减小 ,表现为下切牙唇倾 ,上切牙唇倾度减小 ,下颌磨牙近中移动 ,而上颌磨牙无明显远中移动。在覆盖改变量中骨的改变占 5 5 .5 6 % ,在磨牙关系改变量中骨的改变占 5 6 .4 5 %。 3)垂直方向上 ,腭平面及下颌平面均无变化 ,而牙合平面顺时针旋转 ,上颌切牙及下颌磨牙升长 ,上颌磨牙与下颌切牙无明显压低 ,下面高增加。 4 )下颌骨的长度增加。 5 )软组织侧貌突度减小。结论 :1)Herbst矫治器能迅速、有效地矫治AngleⅡ类错牙合 ;2 )颌间关系的改善是骨骼、牙牙合效应共同作用的结果 ;3)该矫治器能促进下颌骨的生长 。 展开更多
关键词 HERBST矫治器 治疗 angleⅡ类错He 临床应用 头影测量
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成人骨性Angle Ⅲ类错合咀嚼运动的肌电变化研究 被引量:11
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作者 周彦恒 傅民魁 《口腔医学纵横》 CSCD 1995年第2期113-115,共3页
本研究对30名成人骨性AngleⅢ类错合患者咀嚼运动和正中 位大力咬合的肌电活动进行测量,并与正常 成人比较发现:成人骨性AngleⅢ类错 正中 位大力咬合时嚼肌、颞肌前后束肌电活动均较正常成人低,肌力较小。咀嚼运动... 本研究对30名成人骨性AngleⅢ类错合患者咀嚼运动和正中 位大力咬合的肌电活动进行测量,并与正常 成人比较发现:成人骨性AngleⅢ类错 正中 位大力咬合时嚼肌、颞肌前后束肌电活动均较正常成人低,肌力较小。咀嚼运动时.成人骨性AngleⅢ类错 嚼肌、颞肌肌电活动均较正常成人低,咀嚼循环活动期较正常成人长.间歇期较正常成人短。 展开更多
关键词 angleⅢ类 错HE 大力咬合 咀嚼运动
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下颌前伸矫治器治疗AngleⅡ类错 被引量:4
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作者 陈国新 袁文钧 +2 位作者 贺红 华先明 沈真祥 《口腔医学纵横》 CSCD 2001年第2期135-136,共2页
目的 :了解下颌前伸矫治器 (MandibularProtractionAppliance ,MPA)对AngleⅡ类错 牙合的治疗效果。方法 :选择 13例AngleⅡ类错牙合病人 ,男 6例 ,女 7例 ,最大 13岁 ,最小 10岁 ,均为替牙晚期或恒牙早期。X线头影测量显示主要为下颌... 目的 :了解下颌前伸矫治器 (MandibularProtractionAppliance ,MPA)对AngleⅡ类错 牙合的治疗效果。方法 :选择 13例AngleⅡ类错牙合病人 ,男 6例 ,女 7例 ,最大 13岁 ,最小 10岁 ,均为替牙晚期或恒牙早期。X线头影测量显示主要为下颌后缩及轻微上颌前突 ,左手腕片显示为生长发育高峰期或高峰前期 ,所有病人用下颌前伸矫治器进行治疗。结果 :平均疗程 5 .6个月 ,X线头影测量结果主要为SNA增大 ,ANB减小 ,Go -Co增大 ,经统计学处理有显著差异 ;U1-L1、U1-NA(角度 )、U1-NA(距离 )、L1-NB(角度 )、L1-NB(距离 )均无明显改变。结论 :下颌前伸矫治器治疗早期Angle二类错 牙合可取得明显的骨骼改变。 展开更多
关键词 下颌前伸矫治器 angle II类错HE 口腔正畸
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骨性Angle III类错替牙期患者语音功能的研究 被引量:2
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作者 陈杰 范存晖 王兰磊 《实用口腔医学杂志》 CAS CSCD 北大核心 2003年第5期432-434,共3页
目的 :探讨替牙期AngleⅢ类骨性反牙合对语音功能是否有影响及影响程度 ;对发音异常的语音进行声学分析。方法 :3 8名替牙期AngleⅢ类骨性反 牙合患者为研究对象 ,并随机选择 40名替牙期正常牙合儿童做对照组。由语音专家对 2组儿童的... 目的 :探讨替牙期AngleⅢ类骨性反牙合对语音功能是否有影响及影响程度 ;对发音异常的语音进行声学分析。方法 :3 8名替牙期AngleⅢ类骨性反 牙合患者为研究对象 ,并随机选择 40名替牙期正常牙合儿童做对照组。由语音专家对 2组儿童的语音进行判听 ,记录错误音素及错误类型 ,并应用计算机语音工作站对错误音素进行语音声学分析。结果 :①骨性AngleIII类错牙合替牙期患者大多数存在发音异常 ,主要集中于 /z ,c ,s/等咝音上 ;②正常清咝音VOT >0 ,而错牙合组错误音素的VOT =0。结论 :替牙期AngleⅢ类骨性反 展开更多
关键词 骨性angleⅢ类错He 替牙期 语音功能 发音障碍 牙列 嗓音起始时间 VOT
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AngleⅡ类1分类错畸形打开深覆的探讨——Begg细丝弓技术第一步骤治疗 被引量:1
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作者 林界伟 王大为 严开仁 《华西口腔医学杂志》 CAS CSCD 北大核心 1991年第3期210-212,共3页
打开深覆与建立磨牙的中性关系,是Begg 细丝矫正技术治疗 Angle Ⅱ类1分类错第一步骤最重要的目的。循惯例用澳大利亚特制的0.4mm(0.016吋)细丝上,位于第一磨牙与第二双尖牙交界处弯制一适度的支抗弯曲,然后将弓丝斜插入磨牙颊面... 打开深覆与建立磨牙的中性关系,是Begg 细丝矫正技术治疗 Angle Ⅱ类1分类错第一步骤最重要的目的。循惯例用澳大利亚特制的0.4mm(0.016吋)细丝上,位于第一磨牙与第二双尖牙交界处弯制一适度的支抗弯曲,然后将弓丝斜插入磨牙颊面管内径0.9mm,(0.036吋),并戴用9.4mm(3/8时)轻细颌间牵引橡皮圈来完成这两个目的。为了详细研讨打开深覆的过程,一例患者接受治疗过程中,摄取了一系列的 X 线头颅侧位片,描绘出相应影图,重叠在腭平面。 展开更多
关键词 angleⅡ类1分类错He畸形 深覆He 口腔正畸 Begg细丝弓
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