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The(Homotopy)Fixed Point Set of S^(1)-Actions on Rationally Elliptic 4-Manifolds
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作者 Chen Huimin Liu Xiugui 《南开大学学报(自然科学版)》 北大核心 2025年第3期32-37,共6页
Let X be a closed simply connected rationally elliptic 4-manifold.The rational homotopy type of homotopy fixed point sets X^(hS^(1))is determined,and based on some relations between X^(hS^(1))and X^(S^(1)),the rationa... Let X be a closed simply connected rationally elliptic 4-manifold.The rational homotopy type of homotopy fixed point sets X^(hS^(1))is determined,and based on some relations between X^(hS^(1))and X^(S^(1)),the rational homotopy type of the fixed point set X^(S^(1))is determined. 展开更多
关键词 rationally elliptic 4-manifolds rational homotopy type homotopy fixed point set fixed point set
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A round-trip journey of electrons:Electron catalyzed direct fixation of N_(2)to azos 被引量:2
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作者 Baijing Wu Jinrui Li +5 位作者 Xiaoxue Luo Jingtian Ni Yiting Lu Minhua Shao Cunpu Li Zidong Wei 《Chinese Journal of Catalysis》 2025年第1期386-393,共8页
The triple bond in N_(2)has an extremely high bond energy and is thus difficult to break.N_(2)is commonly converted into NH3 artificially via the Haber-Bosch process,and NH_(3)can be utilized to produce other nitrogen... The triple bond in N_(2)has an extremely high bond energy and is thus difficult to break.N_(2)is commonly converted into NH3 artificially via the Haber-Bosch process,and NH_(3)can be utilized to produce other nitrogen-containing chemicals.Here,we developed an electron catalyzed method to directly fix N_(2)into azos,by pushing and pulling the electron into and from the aromatic halide with the cyclic voltammetry method.The round-trip journey of electron can successfully weaken the triple bond in N_(2)through the electron pushing-induced aryl radical via a“brick trowel”transition state,and then produce the diazonium ions by pulling the electron out from the diazo radical intermediate.Different azos can be synthesized with this developed electron catalyzed approach.This approach provides a novel concept and practical route for the fixation of N_(2)at atmospheric pressure into chemical products valuable for industrial and commercial applications. 展开更多
关键词 fixed N_(2) AZO Electron catalyzed strategy "Brick trowel"transition state Arylradicals
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Coincidence Point and Common Fixed Point Theorems on b-Metric-like Spaces
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作者 LUO Ting 《应用数学》 北大核心 2025年第3期831-840,共10页
In this paper,we establish common fixed point theorems for expansive map?pings on b-metric-like space and coincidence point for f-weakly isotone increasing mappings in partially ordered b-metric-like space.The main re... In this paper,we establish common fixed point theorems for expansive map?pings on b-metric-like space and coincidence point for f-weakly isotone increasing mappings in partially ordered b-metric-like space.The main results generalize and extend several well-known comparable results from the existing literature.Moreover,some examples are provided to illustrate the main results. 展开更多
关键词 b-metric-like space Partially ordered b-metric-like space Expansive mapping f-weakly isotone mapping Coincidence point Common fixed point
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MEMS microwave power detection chip based on fixed beams and its model
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作者 Qirui Xu Zhiyin Ding Debo Wang 《Journal of Semiconductors》 2025年第6期87-95,共9页
In order to solve the problems of low overload power in MEMS cantilever beams and low sensitivity in traditional MEMS fixed beams,a novel MEMS microwave power detection chip based on the dual-guided fixed beam is desi... In order to solve the problems of low overload power in MEMS cantilever beams and low sensitivity in traditional MEMS fixed beams,a novel MEMS microwave power detection chip based on the dual-guided fixed beam is designed.A gap between guiding beams and measuring electrodes is designed to accelerate the release of the sacrificial layer,effectively enhanc-ing chip performance.A load sensing model for the MEMS fixed beam microwave power detection chip is proposed,and the mechanical characteristics are analyzed based on the uniform load applied.The overload power and sensitivity are investi-gated using the load sensing model,and experimental results are compared with theoretical results.The detection chip exhibits excellent microwave characteristic in the 9-11 GHz frequency band,with a return loss less than-10 dB.At a signal fre-quency of 10 GHz,the theoretical sensitivity is 13.8 fF/W,closely matching the measured value of 14.3 fF/W,with a relative error of only 3.5%.These results demonstrate that the proposed load sensing model provides significant theoretical support for the design and performance optimization of MEMS microwave power detection chips. 展开更多
关键词 detection chip dual-guided fixed beam MEMS load sensing model sensitivity
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Fixed Neural Network Image Steganography Based on Secure Diffusion Models
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作者 Yixin Tang Minqing Zhang +2 位作者 Peizheng Lai Ya Yue Fuqiang Di 《Computers, Materials & Continua》 2025年第9期5733-5750,共18页
Traditional steganography conceals information by modifying cover data,but steganalysis tools easily detect such alterations.While deep learning-based steganography often involves high training costs and complex deplo... Traditional steganography conceals information by modifying cover data,but steganalysis tools easily detect such alterations.While deep learning-based steganography often involves high training costs and complex deployment.Diffusion model-based methods face security vulnerabilities,particularly due to potential information leakage during generation.We propose a fixed neural network image steganography framework based on secure diffu-sion models to address these challenges.Unlike conventional approaches,our method minimizes cover modifications through neural network optimization,achieving superior steganographic performance in human visual perception and computer vision analyses.The cover images are generated in an anime style using state-of-the-art diffusion models,ensuring the transmitted images appear more natural.This study introduces fixed neural network technology that allows senders to transmit only minimal critical information alongside stego-images.Recipients can accurately reconstruct secret images using this compact data,significantly reducing transmission overhead compared to conventional deep steganography.Furthermore,our framework innovatively integrates ElGamal,a cryptographic algorithm,to protect critical information during transmission,enhancing overall system security and ensuring end-to-end information protection.This dual optimization of payload reduction and cryptographic reinforcement establishes a new paradigm for secure and efficient image steganography. 展开更多
关键词 Image steganography fixed neural network secure diffusion models ELGAMAL
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Fractional Discrete-Time Analysis of an Emotional Model Built on a Chaotic Map through the Set of Equilibrium and Fixed Points
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作者 Shaher Momani Rabha W.Ibrahim Yeliz Karaca 《Computer Modeling in Engineering & Sciences》 2025年第4期809-826,共18页
Fractional discrete systems can enable the modeling and control of the complicated processes more adaptable through the concept of versatility by providing systemdynamics’descriptions withmore degrees of freedom.Nume... Fractional discrete systems can enable the modeling and control of the complicated processes more adaptable through the concept of versatility by providing systemdynamics’descriptions withmore degrees of freedom.Numerical approaches have become necessary and sufficient to be addressed and employed for benefiting from the adaptability of such systems for varied applications.A variety of fractional Layla and Majnun model(LMM)system kinds has been proposed in the current work where some of these systems’key behaviors are addressed.In addition,the necessary and sufficient conditions for the stability and asymptotic stability of the fractional dynamic systems are investigated,as a result of which,the necessary requirements of the LMM to achieve constant and asymptotically steady zero resolutions are provided.As a special case,when Layla and Majnun have equal feelings,we propose an analysis of the system in view of its equilibrium and fixed point sets.Considering that the system has marginal stability if its eigenvalues have both negative and zero real portions,it is demonstrated that the system neither converges nor diverges to a steady trajectory or equilibrium point.It,rather,continues to hover along the line separating stability and instability based on the fractional LMM system. 展开更多
关键词 Fractional difference system fractional differential operators fractional calculus chaotic map EQUILIBRIUM fixed point sets nyquist plot routh-Hurwitz criterion
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2.1 billion fixed assets landing,Xinao shares reveal new growth points for textile enterprises
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作者 Qiu Shuchen 《China Textile》 2025年第6期32-34,共3页
Xin'ao Co.,Ltd.(603889),Iocated in Jiaxing City,Zhejiang Province,is a wellestablished enterprise in the wool textile industry.It focuses on the entire wool textile supply chain,integrating wool procurement,wool t... Xin'ao Co.,Ltd.(603889),Iocated in Jiaxing City,Zhejiang Province,is a wellestablished enterprise in the wool textile industry.It focuses on the entire wool textile supply chain,integrating wool procurement,wool top production,wool top modification,dyeing and finishing,and spinning,After more than thirty years of development,it has gradually formed a large-scale,market-oriented textile eco-system with Xin'ao Co.,Ltd. as the core,with its subsidia ries specializing in different production and sales functions. 展开更多
关键词 fixed assets wool top production wool textile industry supply chain procurement textile enterprises production sales functions growth points
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Investigation of flight stability for fixed canard dual-spin projectile via CFD/RBD coupled method
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作者 Gang Wang Tengyue Zhang +2 位作者 Tianyu Lin Haizhen Lin Ke Xi 《Defence Technology(防务技术)》 2025年第11期1-18,共18页
In this paper,a high-fidelity computational fluid dynamics(CFD)and rigid body dynamics(RBD)coupled platform for virtual flight simulation is developed to investigate the flight stability of fixed canard dual-spin proj... In this paper,a high-fidelity computational fluid dynamics(CFD)and rigid body dynamics(RBD)coupled platform for virtual flight simulation is developed to investigate the flight stability of fixed canard dual-spin projectile.The platform's reliability is validated by reproducing the characteristic resonance instability of such projectiles.By coupling the solution of the Unsteady Reynolds-Averaged Navier-Stokes equations and the seven-degree-of-freedom RBD equations,the virtual flight simulations of fixed canard dual-spin projectiles at various curvature trajectories are achieved,and the dynamic mechanism of the trajectory following process is analyzed.The instability mechanism of the dynamic instability during trajectory following process of the fixed canard dual-spin projectile is elucidated by simulating the rolling/coning coupled forced motion,and subsequently validated through virtual flight simulations.The findings suggest that an appropriate yaw moment can drive the projectile axis to precession in the tangential direction of the trajectory,thereby enhancing the trajectory following stability.However,the damping of the projectile attains its minimum value when the forward body equilibrium rotational speed(-128 rad/s)is equal to the negative of the fast mode frequency of the projectile.Insufficient damping leads to the fixed canard dual-spin projectile exiting the dynamic stability domain during the trajectory following,resulting in weakly damped instability.Keeping the forward body not rotating or increasing the spin rates to-192 rad/s can enhance the projectile's damping,thereby improving its dynamic stability. 展开更多
关键词 fixed canard dual-spin projectile CFD/RBD coupled method Virtualflight simulation Following stability Dynamic stability
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Relativistic non-Fermi liquid fixed point in(2+1)-dimensional birefringent Dirac fermions interacting with electromagnetic fields
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作者 Wan-Zi Sun Kai Liu +1 位作者 Wu-Ming Liu Cheng-Xi Li 《Chinese Physics B》 2025年第5期524-532,共9页
The system consisting of(2+1)-dimensional quasirelativistic birefringent Dirac fermions with Coulomb interactions and retarded current–current interactions is described by a quantum field theory similar to reduced qu... The system consisting of(2+1)-dimensional quasirelativistic birefringent Dirac fermions with Coulomb interactions and retarded current–current interactions is described by a quantum field theory similar to reduced quantum electrodynamics.We used the perturbative renormalization group method to study the low-energy behavior of the system and found that it flows to a fixed point of the non-Fermi liquid composed of relativistic pseudospin-1/2 Dirac fermions in the deep infrared limit.At the fixed point,the fermion Green function exhibits a finite anomalous dimension,and the residue of the quasiparticle pole vanishes in a power-law fashion.Our research provides new theoretical perspectives for understanding the origin of spin-1/2 fermions in the standard model. 展开更多
关键词 non-Fermi liquid fixed point birefringent Dirac fermions perturbative renormalization group Fermi velocity renormalization
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Validation Analysis of Gas Chromatography Method for Determining 8 Benzene Derivatives in Fixed Pollution Source Exhaust Gas
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作者 Wenshuai XU Juan LI Ziyan LIN 《Meteorological and Environmental Research》 2025年第4期37-39,42,共4页
Benzene derivatives are volatile organic compounds commonly present in the atmospheric environment,which are toxic and complex in composition.They have become a key regulatory object in China s atmospheric environment... Benzene derivatives are volatile organic compounds commonly present in the atmospheric environment,which are toxic and complex in composition.They have become a key regulatory object in China s atmospheric environment management.In this paper,Shimadzu Nexis GC-2030 gas chromatography was used to simultaneously detect eight benzene derivatives.According to the Environmental Monitoring—Technical Guideline on Drawing and Revising Analytical Method Standards(HJ 168-2010),the monitoring methods for benzene,toluene,ethylbenzene,p-xylene,m-xylene,isopropylbenzene,o-xylene,and styrene in the Stationary Source Emission—Determination of Benzene and Its Analogies—Bags Sampling/Direct Injection—Gas Chromatography(HJ 1261-2022)are verified,and their linear relationships,detection limits,precision and accuracy are analyzed. 展开更多
关键词 Benzene derivatives fixed pollution source exhaust gas Method validation
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Fixed point results for asymptotically regular mappings in abstract metric spaces
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作者 HAN Yan DAI Ting-ting XU Shao-yuan 《Applied Mathematics(A Journal of Chinese Universities)》 2025年第3期632-644,共13页
In this paper,various extended contractions are introduced as generalizations of some existing contractions given by Kannan,Ciric,Reich and Gornicki,et al.Then,several meaningful results about asymptotically regular m... In this paper,various extended contractions are introduced as generalizations of some existing contractions given by Kannan,Ciric,Reich and Gornicki,et al.Then,several meaningful results about asymptotically regular mappings in cone metric spaces over Banach algebras are obtained,weakening the completeness of the spaces and the continuity of the mappings.Moreover,some nontrivial examples are showed to verify the innovation of the new concepts and our fxed point theorems. 展开更多
关键词 asymptotic regularity fixed point cone metric spaces over Banach algebras
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Enhancing Coating Inoculation for Improved Nitrogen-Fixing Efficiency of Rhizobia in Soybean (Glycine max L.)
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作者 Anne Nora Ndokon Bikang Liliane Meguekam Tekam +1 位作者 Alain-Martial Sontsa-Donhoung Dieudonné Nwaga 《American Journal of Plant Sciences》 2025年第2期245-262,共18页
Plant biofertilization involves introducing compounds containing living mi-croorganisms into the coating medium to sustainably enhance plant production and soil health. This is a complex process that undergoes multipl... Plant biofertilization involves introducing compounds containing living mi-croorganisms into the coating medium to sustainably enhance plant production and soil health. This is a complex process that undergoes multiple stages of development before yielding a final product. The final biofertilizer is used by legumes-protein-rich crops in symbiosis with rhizobia to enable biological nitrogen fixation increasing natural soil fertility. This study aims to determine the optimal formulation of a rhizobial biofertilizer to improve the performance of soybean (Glycine max L. cv. Docko). To this end, soybean seeds obtained from IRAD were coated with different formulations derived from locally sourced materials. Palm kernel oil was used as an adhesive in one group, while corn powder served as an adhesive in another. The coated seeds were then sown in the field. The results indicate that the combination of pigeon pea powder + sugarcane molasses, with palm kernel oil as an adhesive, produced the best nodulation (nitrogen fixation). This formulation also led to significant improvements in growth (+350%) and total nitrogen content (+1100%) compared to the bacterial broth inoculum control (B0) (P ≤ 0.01). These findings represent a significant advancement in improving nitrogen-fixing bacterial inoculants and enhancing soil fertility for the sustainable cultivation of soybeans in this tropical soil. 展开更多
关键词 FORMULATION BIOFERTILIZER N-fixing RHIZOBIA COATING Growth
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CARISTI TYPE HYBRID FIXED POINT THEOREMS IN MENGERPROBABILISTIC METRIC SPACE
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作者 石川 《Applied Mathematics and Mechanics(English Edition)》 SCIE EI 1997年第2期201-209,共9页
This paper brings forward the concept of Caristi type hybrid fixed point in M-PM-space, by giving two hybrid fixed point theorems and two common hybrid fixed point theorems of sequences of set-valued mappings, the the... This paper brings forward the concept of Caristi type hybrid fixed point in M-PM-space, by giving two hybrid fixed point theorems and two common hybrid fixed point theorems of sequences of set-valued mappings, the theorems improve and generalize the Caristi's fixed point and correspond to recent important results. 展开更多
关键词 probabilistic metric space Menger space Caristi's fixed point theorem hybrid fixed point common hybrid fixed point
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Integrated Guidance and Control of Homing Missiles Against Ground Fixed Targets 被引量:23
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作者 侯明哲 段广仁 《Chinese Journal of Aeronautics》 SCIE EI CAS CSCD 2008年第2期162-168,共7页
This paper presents a scheme of integrated guidance and autopilot design for homing missiles against ground fixed targets. An integrated guidance and control model in the pitch plane is formulated and further changed ... This paper presents a scheme of integrated guidance and autopilot design for homing missiles against ground fixed targets. An integrated guidance and control model in the pitch plane is formulated and further changed into a normal form by nonlinear coordinate transformation. By adopting the sliding mode control approach, an adaptive nonlinear control law of the system is designed so that the missile can hit the target accurately with a desired impact attitude angle. The stability analysis of the closed-loop system is also conducted. The numerical simulation has confirmed the usefulness of the proposed design scheme. 展开更多
关键词 integrated guidance and control pitch plane ground fixed target nonlinear adaptive
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浅剖中定位FIX号方法研究 被引量:6
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作者 薛花 文鹏飞 +1 位作者 张宝金 刘胜旋 《物探化探计算技术》 CAS CSCD 2014年第1期92-94,共3页
FIX号是深水浅剖资料与钻井、多波束以及其他地质资料对比的标志号。野外采集的SEGY格式的浅剖数据没有记录导航FIX号信息,未记录FIX号信息的SEGY数据无法为实际目标区域其他数据相对应,不便于为后续资料解释提供可对比的地理位置,从而... FIX号是深水浅剖资料与钻井、多波束以及其他地质资料对比的标志号。野外采集的SEGY格式的浅剖数据没有记录导航FIX号信息,未记录FIX号信息的SEGY数据无法为实际目标区域其他数据相对应,不便于为后续资料解释提供可对比的地理位置,从而降低识别天然气水合物层、天然气渗漏或扩散引起的沉积物声学异常特征的精度。这里提出了利用时间信息在浅剖中定位FIX号的方法,根据导航数据中FIX号、时间信息和浅剖数据中炮号、时间信息,通过二者时间信息进行匹配来标定FIX号。在linux系统下,利用awk编程语言编写模块程序与Focus 5.4地震资料处理系统模块结合使用,用于提取每条剖面的每道道头时间和相对应的导航数据时间;再用awk编程语言编写特殊处理模块程序,将地震道头时间与导航FIX号时间进行匹配处理,将匹配好的FIX信息依次植入浅剖道头数据中。该方法为资料的综合解释提供了准确的FIX号信息和可对比的地理位置。 展开更多
关键词 fix 浅地层剖面 时间信息
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颈椎前路减压Inter Fix椎体间融合 被引量:6
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作者 陈德玉 贾连顺 +5 位作者 倪斌 肖建如 沈强 叶晓健 陈雄生 王新伟 《临床骨科杂志》 2001年第1期17-19,共3页
目的 观察颈椎前路减压InterFix椎体间融合的稳定性及融合效果。方法 采用前路减压InterFix椎体间融合术治疗颈椎病及颈椎间盘突出症 2 7例 ,术后定期摄颈椎X线片检查 ,观察手术椎节的稳定性和融合情况。结果 随访 7~ 19个月 ,术后... 目的 观察颈椎前路减压InterFix椎体间融合的稳定性及融合效果。方法 采用前路减压InterFix椎体间融合术治疗颈椎病及颈椎间盘突出症 2 7例 ,术后定期摄颈椎X线片检查 ,观察手术椎节的稳定性和融合情况。结果 随访 7~ 19个月 ,术后次日即下床活动 ,手术节段稳定 ,术后 3~ 4个月融合。结论 InterFix颈椎椎体间固定融合技术使施术椎节立即稳定 ,避免了自体植骨引起的并发症 ,可作为颈椎前路减压后椎体间融合的一种方法。 展开更多
关键词 INTER fix 颈椎病 颈椎间盘突出症 脊柱融合术 治疗
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腰髂固定联合INFIX治疗Tile B型骨盆骨折的临床研究
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作者 徐耀宁 黄森 +2 位作者 池伟东 张彬 吴俊哲 《系统医学》 2025年第3期104-106,110,共4页
目的分析腰髂固定联合内置固定架(internal fixator,INFIX)治疗Tile B型骨盆骨折的临床疗效。方法回顾性选取2021年1月—2024年6月中山市中医院收治的55例Tile B型骨盆骨折患者的临床资料。根据治疗方法分为两组,对照组(28例)采用骶髂... 目的分析腰髂固定联合内置固定架(internal fixator,INFIX)治疗Tile B型骨盆骨折的临床疗效。方法回顾性选取2021年1月—2024年6月中山市中医院收治的55例Tile B型骨盆骨折患者的临床资料。根据治疗方法分为两组,对照组(28例)采用骶髂关节螺钉联合外固定架治疗,观察组(27例)采用腰髂固定联合INFIX治疗。比较两组临床疗效、疼痛评分、骨盆功能恢复情况及并发症发生情况。结果观察组的总有效率达96.29%(26/27),较对照组的71.43%(20/28)更高,差异有统计学意义(χ^(2)=4.527,P<0.05)。观察组的疼痛评分低于对照组,且其Majeed骨盆功能评分高于对照组,差异均有统计学意义(P均<0.05)。观察组并发症的发生率低于对照组,差异有统计学意义(P<0.05)。结论腰髂固定联合INFIX治疗Tile B型骨盆骨折在临床疗效、疼痛缓解、功能恢复及安全性方面优于骶髂关节螺钉联合外固定架。 展开更多
关键词 骨盆骨折 Tile B型 腰髂固定 内置固定架 疗效 并发症
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被动全向浮标LOFIX定位精度仿真分析 被引量:10
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作者 胡柱喜 孙明太 +1 位作者 苏维国 刘京莲 《电光与控制》 北大核心 2009年第12期26-29,共4页
在LOFIX定位原理的基础上,建立了被动全向浮标LOFIX定位数学模型,通过计算机仿真分析了浮标接收信号声强比、声纳作用距离以及浮标布放阵形对被动全向浮标LOFIX定位精度的影响,并结合实际应用对仿真结果进行分析验证,结论为:反潜... 在LOFIX定位原理的基础上,建立了被动全向浮标LOFIX定位数学模型,通过计算机仿真分析了浮标接收信号声强比、声纳作用距离以及浮标布放阵形对被动全向浮标LOFIX定位精度的影响,并结合实际应用对仿真结果进行分析验证,结论为:反潜机在布放被动全向浮标时的最优布放间距应该是在1~1.5倍浮标作用距离之间;如果决定采用被动全向浮标LOFIX定位,则应尽量避免将浮标布放成直线阵。这些结论将为反潜机执行搜潜作战任务时,合理选择浮标的布放间隔和布放阵形提供理论依据。 展开更多
关键词 LOfix定位 定位精度 声纳浮标 仿真分析
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基于C-FIX模型的黑龙江省森林植被净初级生产力遥感估算 被引量:22
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作者 张冬有 冯仲科 +2 位作者 李亦秋 张丽娟 董斌 《林业科学》 EI CAS CSCD 北大核心 2011年第7期13-19,共7页
以黑龙江省森林资源为研究对象,利用ETM+、DEM和气象数据等资料,以C-FIX模型为基础,估算黑龙江省2000年5—9月的森林植被NPP,并将估算结果与MODIS的NPP产品进行对比分析。结果表明:5—9月林地总NPP为69.75×1012gC,最大值出现在6月,... 以黑龙江省森林资源为研究对象,利用ETM+、DEM和气象数据等资料,以C-FIX模型为基础,估算黑龙江省2000年5—9月的森林植被NPP,并将估算结果与MODIS的NPP产品进行对比分析。结果表明:5—9月林地总NPP为69.75×1012gC,最大值出现在6月,占5—9月NPP总量的27.23%,6—8月是NPP的主要积累月份;有林地NPP占林地总量的87.44%,灌木林地占10.41%,疏林地占1.63%,其他林地占0.52%;MODIS的NPP产品与模型估算值之间的均方差根为17.12,模型模拟值误差为MODISNPP产品值的3.92%~5.85%,模型估算精度较高。 展开更多
关键词 净初级生产力 遥感估测 C-fix模型 黑龙江省
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正确放置Gyne Fix IN IUD 60例的体会 被引量:13
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作者 杜天竹 刘素英 《实用妇产科杂志》 CAS CSCD 北大核心 2002年第5期309-310,共2页
关键词 宫内节育器 避孕手术 GYNE fix
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