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Vessel fusion tracking with a dual-frequency high-frequency surface wave radar and calibrated by an automatic identification system 被引量:3
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作者 ZHANG Hui LIU Yongxin +1 位作者 JI Yonggang WANG Linglin 《Acta Oceanologica Sinica》 SCIE CAS CSCD 2018年第7期131-140,共10页
High-frequency surface wave radar(HFSWR) and automatic identification system(AIS) are the two most important sensors used for vessel tracking.The HFSWR can be applied to tracking all vessels in a detection area,wh... High-frequency surface wave radar(HFSWR) and automatic identification system(AIS) are the two most important sensors used for vessel tracking.The HFSWR can be applied to tracking all vessels in a detection area,while the AIS is usually used to verify the information of cooperative vessels.Because of interference from sea clutter,employing single-frequency HFSWR for vessel tracking may obscure vessels located in the blind zones of Bragg peaks.Analyzing changes in the detection frequencies constitutes an effective method for addressing this deficiency.A solution consisting of vessel fusion tracking is proposed using dual-frequency HFSWR data calibrated by the AIS.Since different systematic biases exist between HFSWR frequency measurements and AIS measurements,AIS information is used to estimate and correct the HFSWR systematic biases at each frequency.First,AIS point measurements for cooperative vessels are associated with the HFSWR measurements using a JVC assignment algorithm.From the association results of the cooperative vessels,the systematic biases in the dualfrequency HFSWR data are estimated and corrected.Then,based on the corrected dual-frequency HFSWR data,the vessels are tracked using a dual-frequency fusion joint probabilistic data association(JPDA)-unscented Kalman filter(UKF) algorithm.Experimental results using real-life detection data show that the proposed method is efficient at tracking vessels in real time and can improve the tracking capability and accuracy compared with tracking processes involving single-frequency data. 展开更多
关键词 vessel tracking high-frequency surface wave radar automatic identification system joint probabilistic data association unscented Kalman filter
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A New Theoretical Technique for the Measurement of High-Frequency Relic Gravitational Waves 被引量:3
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作者 R. Clive Woods Robert M L Baker +3 位作者 Fangyu Li Gary V Stephenson Eric W Davis Andrew W Beckwith 《Journal of Modern Physics》 2011年第6期498-518,共21页
Under most models of the early universe evolution, high-frequency gravitational waves (HFGWs) were produced. They are referred to as “relic” high-frequency gravitational waves or HFRGWs and their detection and measu... Under most models of the early universe evolution, high-frequency gravitational waves (HFGWs) were produced. They are referred to as “relic” high-frequency gravitational waves or HFRGWs and their detection and measurement could provide important information on the origin and development of our Universe – information that could not otherwise be obtained. So far three instruments have been built to detect and measure HFRGWs, but so far none of them has achieved the required sensitivity. This paper concerns another detector, originally proposed by Baker in 2000 and patented, which is based upon a recently discovered physical effect (the Li effect);this detector has accordingly been named the “Li-Baker detector.” The detector has been a joint development effort by the P. R. China and the United States HFGW research teams. A rigorous examination of the detector’s performance is important in the ongoing debate over the value of attempting to construct a Li-Baker detector and, in particular, an accurate prediction of its sensitivity in the presence of significant noise will decide whether the Li-Baker detector will be capable of detecting and measuring HFRGWs. The potential for useful HFRGW measurement is theoretically confirmed. 展开更多
关键词 high-frequency GRAVITATIONAL waveS high-frequency Relic GRAVITATIONAL wave Measurement Primordial GRAVITATIONAL waveS Microwaves COSMOLOGY General RELATIVITY
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Value of High-Frequency Relic Gravitational Wave (HFRGW) Detection to Astrophysics and Fabrication and Utilization of the Li-Baker HFRGW Detector 被引量:2
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作者 Andrew Walcott Beckwith Robert M. L. Baker Jr 《Journal of High Energy Physics, Gravitation and Cosmology》 2020年第1期103-122,共20页
Up to the present time gravitational-wave detectors, such as LIGO and Virgo, have been sensitive to frequencies on the order of a few thousand to a small fraction of an Hz. They have been most effective in the study o... Up to the present time gravitational-wave detectors, such as LIGO and Virgo, have been sensitive to frequencies on the order of a few thousand to a small fraction of an Hz. They have been most effective in the study of black-hole mergers. We suggest that high-frequency relic gravitational wave (HFRGW) detectors be developed, especially the Li-Baker HFRGW detector, in the gigahertz and higher frequency range. We believe collecting cosmological, primordial observational data especially generated during the first few seconds after the beginning of our Universe is extremely important. One motivation for this paper is, therefore, that we are confident that observation of relic gravitational waves will provide vital information about the birth of our Universe and its early dynamical evolution. Other astrophysical applications of HFRGW detectors involve the entropy growth of the early Universe, an ability to study alternatives to inflation and to provide clues about the symmetries underlying new physics at the highest energies. A working hypothesis or theory, based upon the rollout of our Universe from infinitesimal Planck Length and Planck Time is presented. This theory involves the rapid motion of time and matter during that early time having frequencies on the order of trillions of cycles per second or more. Several alternative HFRGW detectors are described and the proposed Li-Baker HFRGW detector, which is theoretically sensitive to GW amplitudes, A, as small as 10-32, is discussed in detail. Such sensitivity may provide a means for verifying or falsifying the rollout of our Universe working hypothesis. Essentially a combination of theory and experimentation is presented. It is recommended that plans and detailed specifications for the Li-Baker HFRGW detector be prepared in order to expedite its fabrication. 展开更多
关键词 high-frequency GRAVITATIONAL waves DARK Energy DARK Matter Variation of Speed of Time Beyond the Standard Model of COSMOLOGY Early UNIVERSE
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Numerical Study of the High-Frequency Wave Loads and Ringing Response of A Bottom-Hinged Vertical Cylinder in Focused Waves
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作者 ZHANG Yi TENG Bin 《China Ocean Engineering》 SCIE EI CSCD 2020年第4期513-525,共13页
This paper presents a numerical study on the high-frequency wave loads and ringing response of offshore wind turbine foundations exposed to moderately steep transient water waves.Input wave groups are generated by the... This paper presents a numerical study on the high-frequency wave loads and ringing response of offshore wind turbine foundations exposed to moderately steep transient water waves.Input wave groups are generated by the technique of frequency-focusing,and the numerical simulation of focused waves is based on the NewWave model and a Fourier time-stepping procedure.The proposed model is validated by comparison with the published laboratory data.In respect of both the wave elevations and the underlying water particle kinematics,the numerical results are in excellent agreement with the experimental data.Furthermore,the local evolution of power spectra and the transfer of energy into higher frequencies can be clearly identified.Then the generalized FNV theory and Rainey’s model are applied respectively to calculate the nonlinear wave loads on a bottom-hinged vertical cylinder in focused waves.Resonant ringing response excited by the nonlinear high-frequency wave loads is found in the numerical simulation when frequency ratios(natural frequency of the structure to peak frequency of wave spectra)are equal to 3–5.Dynamic amplification factor of ringing response is also investigated for different dynamic properties(natural frequency and damping ratio)of the structure. 展开更多
关键词 high-frequency wave loads ringing response focused wave vertical cylinder
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Scattering of Rayleigh waves by a shallow circular alluvial valley: High-frequency solution
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作者 梁建文 张秋红 李方杰 《Acta Seismologica Sinica(English Edition)》 EI CSCD 2006年第2期183-190,共8页
A high-frequency analytical solution for scattering of Rayleigh waves by a shallow circular alluvial valley was derived using wave function expansion method, and the solution was utilized to analyze the effects of inc... A high-frequency analytical solution for scattering of Rayleigh waves by a shallow circular alluvial valley was derived using wave function expansion method, and the solution was utilized to analyze the effects of incident frequency, width of the valley, and depth of the valley, etc, on the wave scattering. Numerical results showed that, because of the alluvial valley, the distribution of surface displacement at the side where wave arrives becomes relatively complicated, but the displacement amplitude is not large; the distribution of the surface displacement at far side is relatively simple, but the displacement amplitude is relatively large, and in most cases the amplitude is larger than that at the alluvium. 展开更多
关键词 alluvial valley Rayleigh waves SCATTERING high-frequency analytical solution
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High-frequency gravitational waves having large spectral densities and their electromagnetic response
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作者 李芳昱 文毫 方祯云 《Chinese Physics B》 SCIE EI CAS CSCD 2013年第12期104-112,共9页
Various cosmology models, brane oscillation scenarios, interaction of interstellar plasma with intense electromagnetic radiation, and even high-energy physics experiments (e.g., Large Hadron Collider (LHC)) all pr... Various cosmology models, brane oscillation scenarios, interaction of interstellar plasma with intense electromagnetic radiation, and even high-energy physics experiments (e.g., Large Hadron Collider (LHC)) all predict high frequency gravitational waves (HFGWs, i.e., high-energy gravitons) in the microwave band and higher frequency region, and some of them have large energy densities. Electromagnetic (EM) detection to such HFGWs would be suitable due to very high frequencies and large energy densities of the HFGWs. We review several typical EM detection schemes, i.e., inverse Gertsenshtein effect (G-effect), coupling of the inverse G effect with a coherent EM wave, coupling of planar superconducting open cavity with a static magnetic field, cylindrical superconducting closed cavity, and the EM sychro-resonance system, and discuss related minimal detectable amplitudes and sensitivities. Furthermore, we give some new ideas and improvement ways enhancing the possibility of measuring the HFGWs. It is shown that there is still a large room for improvement for those schemes to approach and even reach up the requirement of detection of HFGWs expected by the cosmological models and high-energy astrophysical process. 展开更多
关键词 high-frequency gravitational waves electromagnetic response of high-frequency gravitational waves superconducting microwave cavities synchro-resonance system
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Symmetries in Evolving Space-Time and Their Connection to High-Frequency Gravitational Wave Production
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作者 Andrew Walcott Beckwith 《Journal of High Energy Physics, Gravitation and Cosmology》 2018年第3期492-503,共12页
We claim that the linking of a shrinking prior universe to our own via a wormhole bridge solution of about ten to the minus forty four power seconds permits the formation of a short-term quintessence scalar field. Sym... We claim that the linking of a shrinking prior universe to our own via a wormhole bridge solution of about ten to the minus forty four power seconds permits the formation of a short-term quintessence scalar field. Symmetries allow for creating high-frequency gravitational waves at the onset of inflation, which has consequences in our present cosmological era. This instantaneous energy transfer between prior to present universes permits relic graviton production which we claim is a viable candidate for future propulsion technologies in space craft design. The Big Bang started as the passage of thermal energy from an existing universe into ours resulting in another Big Bang, and helps us understand how a graviton burst can occur in the first place. 展开更多
关键词 WORMHOLE high-frequency GRAVITATIONAL waves (HGW) Symmetry CAUSAL DISCONTINUITY
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Application of High-Frequency Gravitational Waves to the Cataclysmic Event of Our First Encounter with Intelligent Extraterrestrial Beings
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作者 Robert M. L. Baker Bonnie Sue Baker 《Journal of Applied Mathematics and Physics》 2016年第1期110-129,共20页
Three advances are proposed as a pathway to the cataclysmic event of our first encounter with intelligent extraterrestrial beings. First, discovery of very large numbers of extraterrestrial planets, “exoplanets” (po... Three advances are proposed as a pathway to the cataclysmic event of our first encounter with intelligent extraterrestrial beings. First, discovery of very large numbers of extraterrestrial planets, “exoplanets” (possibly as many as10<sup>23</sup> in our Universe);second, introduction of electronic components into the human body evolving into a cybernetic and biological “cyborg,” a model for an extraterrestrial being Cyborgs might allow advanced civilizations to endure hundreds of thousands of years. Third, the recent development of high-frequency gravitational wave (HFGW) detectors, the communication means of choice for an advanced cyborg civilization since they are not easily absorbed like electromagnetic radiation. Six HFGW detectors are presented for application to our first encounter with intelligent extraterrestrial beings. Numerical estimates are made for the failure of extraterrestrial civilizations such that no two exist at the same time (Fermi’s Paradox). It is concluded that there might remain at least ≈1.48 × 10<sup>8</sup> Worlds intercommunicating with HFGWs at any one time in any one region of our Universe. The predicted form of extraterrestrial beings is by means of animaginary, but based upon comprehensively documented and detailed projection of the evolution of “Earthling” homosapiens, to become “cyborgs.” It is proposed that such long-living cyborg forms of intelligent beings would be encountered by us. The first cataclysmic encounter with them is expected to be interception of their interstellar communications. The predicted frequency of intercepted messages under one set of assumptions is at least 1500 per day. After decoding the intercepted messages, keys may be found to improve vastly the present and future quality of life for us earthlings. Advanced beings might utilize direct brain-to-brain communication and it is concluded that research into brain-to-brain communication and HFGW detection are encouraged. 展开更多
关键词 high-frequency Gravitational waves Search for Extraterrestrial Intelligence Gravitational waves EXOPLANETS CYBORG
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High-Frequency Guided Wave Scattering by a Partly Through-Thickness Hole Based on 3D Theory
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作者 张海燕 徐建 马世伟 《Chinese Physics Letters》 SCIE CAS CSCD 2015年第8期94-97,共4页
We present a theoretical investigation of the scattering of high frequency S0 Lamb mode from a circular blind hole defect in a plate based on the 3D theory. The SO wave is incident at the frequency above the A1 mode c... We present a theoretical investigation of the scattering of high frequency S0 Lamb mode from a circular blind hole defect in a plate based on the 3D theory. The SO wave is incident at the frequency above the A1 mode cut-off frequency, in which the popular approximate plate theories are inapplicable. Due to the non-symmetric blind hole defect, the scattered fields will contain higher order converted modes in addition to the fundamental SO and AO modes. The far-field scattering amplitudes of various propagating Lamb modes for different hole sizes are inspected. The results are compared with those of lower frequencies and some different phenomena are found. Two-dimensional Fourier transform (2DFT) results of transient scattered Lamb and SH wave signals agree well with the analytical dispersion curves, which check the validity of the solutions from another point of view. 展开更多
关键词 high-frequency Guided wave Scattering by a Partly Through-Thickness Hole Based on 3D Theory
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A note for the mechanism of high-frequency oscillation instability resulted from absorbing boundary conditions
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作者 谢志南 廖振鹏 《Acta Seismologica Sinica(English Edition)》 CSCD 2008年第3期306-310,333,共6页
In this paper the explanation of the mechanism of high-frequency oscillation instability resulted from absorbing boundary conditions is further improved. And we analytically prove the proposition that for one dimensio... In this paper the explanation of the mechanism of high-frequency oscillation instability resulted from absorbing boundary conditions is further improved. And we analytically prove the proposition that for one dimensional discrete model of elastic wave motion, the module of reflection factor will be greater than 1 in high frequency band when artificial wave velocity is greater than 1.5 times the ratio of discrete space step to discrete time step. Based on the proof, the frequency band in which instability occurs is discussed in detail, showing such high-frequency waves are meaningless for the numerical simulation of wave motion. 展开更多
关键词 absorbing boundary conditions high-frequency oscillation instability wave equation numerical simulation
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重组人干扰素α2b凝胶联合LEEP刀宫颈锥切术对宫颈上皮内瘤样病变合并HPV感染患者免疫功能及炎症指标的影响 被引量:1
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作者 付青 薛鸿涛 任敏 《临床医学研究与实践》 2024年第4期110-113,共4页
目的探讨重组人干扰素α2b凝胶联合子宫颈电热圈环切术(LEEP)刀(超高频电波刀)宫颈锥切术对宫颈上皮内瘤样病变(CIN)合并人乳头瘤病毒(HPV)感染患者免疫功能及炎症指标的影响。方法以随机数字表法将2020年1月至2022年1月收治的86例CIN合... 目的探讨重组人干扰素α2b凝胶联合子宫颈电热圈环切术(LEEP)刀(超高频电波刀)宫颈锥切术对宫颈上皮内瘤样病变(CIN)合并人乳头瘤病毒(HPV)感染患者免疫功能及炎症指标的影响。方法以随机数字表法将2020年1月至2022年1月收治的86例CIN合并HPV感染患者分为对照组和观察组,各43例。对照组采用LEEP刀宫颈锥切术治疗,观察组在对照组基础上联合重组人干扰素α2b凝胶治疗。比较两组的治疗效果。结果观察组的治疗总有效率为97.67%,高于对照组的83.72%(P<0.05)。观察组的阴道微生物恢复率、HPV转阴率均高于对照组,CIN复发率低于对照组(P<0.05)。治疗后,观察组的免疫球蛋白G(IgG)、免疫球蛋白M(IgM)、免疫球蛋白A(IgA)、白细胞介素-12(IL-12)及干扰素-γ(IFN-γ)水平高于对照组,白细胞介素-10(IL-10)水平低于对照组(P<0.05)。两组的不良反应总发生率比较,差异无统计学意义(P>0.05)。结论重组人干扰素α2b凝胶联合LEEP刀宫颈锥切术治疗CIN合并HPV感染患者的疗效显著。 展开更多
关键词 宫颈上皮内瘤样病变 人乳头瘤病毒 超高频电波刀 宫颈锥切术 重组人干扰素α2b凝胶 免疫功能 炎症指标
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胶质瘤术后替莫唑胺化疗与射波刀放疗的效果比较
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作者 赵鸽 陈志功 +2 位作者 杨彦松 李太平 李家骏 《华夏医学》 CAS 2024年第1期177-182,共6页
目的观察胶质瘤术后替莫唑胺(TMZ)化疗与射波刀放疗的近期、远期效果。方法选取87例脑胶质瘤患者,采用抽签法分为化疗组(43例)和放疗组(44例)。化疗组采用TMZ化疗,放疗组采用射波刀放疗,比较两组的各种标志物水平变化及病灶改善情况,以... 目的观察胶质瘤术后替莫唑胺(TMZ)化疗与射波刀放疗的近期、远期效果。方法选取87例脑胶质瘤患者,采用抽签法分为化疗组(43例)和放疗组(44例)。化疗组采用TMZ化疗,放疗组采用射波刀放疗,比较两组的各种标志物水平变化及病灶改善情况,以及随访期间的生存质量、生存周期及不良事件发生情况。结果治疗后,两组的糖类抗原153(CA153)、神经元特异性烯醇化酶(NSE)、天冬酰胺内肽酶(AEP)、肿瘤细胞增殖(Ki-67)等指数以及病灶客观缓解率(ORR)、疾病控制率(DCR)相近,差异均无统计学意义(P>0.05)。但随访期间放疗组的卡氏功能状态(KPS)评分、生活质量(QOL)评分高于化疗组;放疗组体能状况(ZPS)评分及不良事件发生率低于化疗组,差异均有统计学意义(P<0.05)。结论应用TMZ化疗或射波刀放疗对控制胶质瘤患者术后病情进展均有积极意义,但射波刀放疗在提升患者生存质量、延长生存周期、降低不良事件发生风险方面更具临床优势。 展开更多
关键词 胶质瘤 开颅切除术 替莫唑胺化疗 射波刀放疗
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体外冲击波和针刀疗法在慢性跖筋膜炎治疗中的疗效对比研究
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作者 黄伟谦 冷楠楠 +3 位作者 王永强 柏天婷 陈建民 刘国印 《保健医学研究与实践》 2024年第1期65-72,共8页
目的比较体外冲击波疗法(ESWT)和针刀疗法(NKT)在慢性跖筋膜炎(CPF)治疗中的临床疗效。方法选取南京医科大学金陵临床医学院骨科2021年6月—2022年6月收治的48例CPF患者作为研究对象。根据医患沟通结果和患者意向确定具体治疗方案,然后... 目的比较体外冲击波疗法(ESWT)和针刀疗法(NKT)在慢性跖筋膜炎(CPF)治疗中的临床疗效。方法选取南京医科大学金陵临床医学院骨科2021年6月—2022年6月收治的48例CPF患者作为研究对象。根据医患沟通结果和患者意向确定具体治疗方案,然后根据治疗方案将患者分为NKT组(26例)和ESWT组(22例)。ESWT组采用激痛点治疗模式,NKT组采用针刀松解治疗模式。分别于治疗前及治疗后1周、1个月、3个月和6个月时,应用视觉模拟评分法(VAS)评定2组患者足跟静息痛和活动痛程度,应用压痛评分评定足跟压痛程度。结果整体分析发现:2组患者治疗前后足跟静息痛、活动痛和足跟压痛的组间比较及各时间点比较,差异均具有统计学意义(P<0.05)。组内比较:治疗后各随访时间节点,2组患者的足跟静息痛、活动痛和足跟压痛均较治疗前明显改善(P<0.05);2组患者治疗后1个月、3个月和6个月的足跟静息痛、活动痛和足跟压痛程度均低于治疗后1周(P<0.05);2组患者治疗后3个月和6个月的足跟压痛与治疗后1个月相比,差异均无统计学意义(P>0.05);NKT组患者治疗后3个月和6个月的足跟静息痛和活动痛均较治疗后1个月明显改善(P<0.05);ESWT组患者治疗6个月后的足跟静息痛和活动痛程度均较治疗后1个月和3个月增加(P<0.05)。组间比较:治疗后1个月、3个月和6个月时,NKT组患者的足跟静息痛、活动痛和足跟压痛程度均明显低于ESWT组(P<0.05),且随着随访时间延长,2组患者之间的足跟静息痛和活动痛VAS评分差异逐渐增大,但足跟压痛评分间的差异变化不大。结论ESWT和NKT均能有效缓解CPF患者的足跟静息痛、活动痛和足跟压痛,并具有较好的镇痛维持效果,但NKT的中远期镇痛效果和维持效果更佳。 展开更多
关键词 针刀疗法 体外冲击波疗法 慢性跖筋膜炎 静息痛 活动痛 足跟压痛
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高频电波刀手术与冷刀宫颈锥切术治疗宫颈上皮内瘤变的临床效果比较
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作者 陈红 《实用妇科内分泌电子杂志》 2024年第17期14-17,共4页
目的分析高频电波刀手术与冷刀宫颈锥切术治疗宫颈上皮内瘤变(CIN)患者的临床价值。方法选取86例CIN患者,根据随机数字表法分为研究组与对照组,各43例。对照组采用冷刀宫颈锥切术治疗,研究组采用高频电波刀手术治疗。比较两组临床疗效... 目的分析高频电波刀手术与冷刀宫颈锥切术治疗宫颈上皮内瘤变(CIN)患者的临床价值。方法选取86例CIN患者,根据随机数字表法分为研究组与对照组,各43例。对照组采用冷刀宫颈锥切术治疗,研究组采用高频电波刀手术治疗。比较两组临床疗效、围手术期指标及并发症发生情况。结果研究组总有效率略高于对照组,但差异无统计学意义(P>0.05)。研究组术中失血量少于对照组,手术用时短于对照组,切口愈合用时长于对照组,差异有统计学意义(P<0.05)。研究组并发症发生率(2.33%)低于对照组(16.28%),差异有统计学意义(P<0.05)。结论高频电波刀手术与冷刀宫颈锥切术治疗CIN患者均可发挥显著疗效,但高频电波刀手术围手术期指标更具优势,并发症更少,具有较高的临床推广价值。 展开更多
关键词 宫颈上皮内瘤变 高频电波刀手术 冷刀宫颈锥切术
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Simulation of high-frequency gravitational wave detection using modulated Gaussian beam
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作者 吴鸣军 李瑾 蒋青权 《Chinese Physics C》 SCIE CAS CSCD 2023年第10期249-256,共8页
This paper investigates the feasibility of using a Li-Baker detector based on a modulated Gaussian beam to detect gravitational waves in the GHz band.The first-order perturbation photon fluxes(PPF,signal of the detect... This paper investigates the feasibility of using a Li-Baker detector based on a modulated Gaussian beam to detect gravitational waves in the GHz band.The first-order perturbation photon fluxes(PPF,signal of the detector)and the background photon fluxes(BPF,main noise of the detector),which vary with time,and the transverse distance are calculated.The results show that their propagation directions and energy densities are much different in some areas.Apart from BPF,we also consider two other important noises:diffraction noise and shot noise.In the simulation,it is found that the diffraction noise and shot noise are both lower than the signal level.Meanwhile,the main noise(BPF)can be eliminated when the receiving screen is located in certain special transverse areas where the BPF direction is opposite to that of PPF.Thus,the signal to noise ratio(SNR)obtained using our detection method can reach up to 320 in some transverse areas.These results are beneficial for the design of the Li-Baker detector. 展开更多
关键词 high-frequency gravitational waves(HFGWs) transverse perturbative photon flux(PPF) background photons flux(BPF) shot noise diffraction noise
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Investigation of a wideband folded double-ridged waveguide slow-wave system 被引量:1
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作者 何俊 魏彦玉 +1 位作者 宫玉彬 王文祥 《Chinese Physics B》 SCIE EI CAS CSCD 2011年第5期237-243,共7页
The folded double-ridged waveguide structure is presented and its properties used for wide-band traveling-wave tube are investigated. Expressions of dispersion characteristics, normalized phase velocity and interactio... The folded double-ridged waveguide structure is presented and its properties used for wide-band traveling-wave tube are investigated. Expressions of dispersion characteristics, normalized phase velocity and interaction impedance of this structure are derived and numerically calculated. The calculated results using our theory agree well with those obtained by using the 3D electromagnetic simulation software HFSS. Influences of the ridge-loaded area and broad-wall dimensions on the high frequency characteristics of the novel slow-wave structure are discussed. It is shown that the folded double-ridged waveguide structure has a much wider relative passband than the folded waveguide slow-wave structure and a relative passband of 67% could be obtained, indicating that this structure can operate in broad-band frequency ranges of beam-wave interaction. The small signal gain property is investigated for ensuring the improvement of bandwidth. Meanwhile, with comparable dispersion characteristics, the transverse section dimension of this novel structure is much smaller than that of conventional one, which indicates an available way to reduce the weight of traveling-wave tube. 展开更多
关键词 millimeter wave traveling-wave tube slow-wave structure folded waveguide high-frequency characteristics
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Effects of ultrasonic waves on carbon dioxide solubility in brine at different pressures and temperatures
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作者 Hossein Hamidi Erfan Mohammadian +6 位作者 Amin Sharifi Haddad Roozbeh Rafati Amin Azdarpour Panteha Ghahri Adi Putra Pradana Bastian Andoni Chingis Akhmetov 《Petroleum Science》 SCIE CAS CSCD 2017年第3期597-604,共8页
The adverse impacts of CO2 emission on the global warming highlight the importance of carbon capture and storage technology and geological storage of CO2 under solubility trapping mechanisms. Enhancing the solubility ... The adverse impacts of CO2 emission on the global warming highlight the importance of carbon capture and storage technology and geological storage of CO2 under solubility trapping mechanisms. Enhancing the solubility of CO2 in formation water has always been the focus of research in the area of CO2 sequestration. Ultrasound techniques are one of the environmentally friendly methods that use high-intensity acoustic waves to improve gas solubility in liquids. Ultrasonic waves can alter the properties of different phases that lead to chemical reactions and provide a means to increase the solubility of CO2 in connate water. In this study, we investigated the effects of ultrasound on the solubility of CO2 in connate water under different conditions of pressure, temperature, and salinity. The results showed that the solubility of CO2 was improved with increasing pressure under ultrasonic effects.However, the solubility of CO2 was inversely proportional to the increase in brine salinity and temperature. Therefore,it was concluded that the solubility of CO2 might be enhanced in the presence of ultrasound. 展开更多
关键词 Carbon dioxide CO2 sequestration Ultrasound high-frequency waves SOLUBILITY
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How a Laser Physics Induced Kerr-Newman Black Hole Can Release Gravitational Waves without Igniting the Black Hole Bomb (Explosion of a Mini Black Hole in a Laboratory)
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作者 Andrew Walcott Beckwith 《Journal of High Energy Physics, Gravitation and Cosmology》 2018年第4期743-778,共36页
Note, that micro black holes last within micro seconds, and that we wish to ascertain how to build, in a laboratory, a black hole, which may exist say at least up to 10^?1 seconds and provide a test bed as to early un... Note, that micro black holes last within micro seconds, and that we wish to ascertain how to build, in a laboratory, a black hole, which may exist say at least up to 10^?1 seconds and provide a test bed as to early universe gravitational theories. First of all, it would be to determine, if the mini black hole bomb, would spontaneously occur, unless the Kerr-Newmann black hole were carefully engineered in the laboratory. Specifically, we state that this paper is modeling the creation of an actual Kerr Newman black hole via laser physics, or possibly by other means. We initiate a model of an induced Kerr-Newman black Holes, with specific angular momentum J, and then from there model was to what would happen as to an effective charge, Q, creating an E and B field, commensurate with the release of GWs. The idea is that using a frame of reference trick, plus E + i B = ?function of the derivative of a complex valued scalar field, as given by Appell, in 1887, and reviewed by Whittaker and Watson, 1927 of their “A Course of Modern Analysis” tome that a first principle identification of a B field, commensurate with increase of thermal temperature, T, so as to have artificially induced GW production. This is compared in part with the Park 1955 paper of a spinning rod, producing GW, with the proviso that both the spinning rod paper, and this artificial Kerr-Newman Black hole will employ the idea of lasers in implementation of their respective GW radiation. The idea is in part partly similar to an idea the author discussed with Dr. Robert Baker, in 2016 with the difference that a B field would be generated and linked to effects linked with induced spin to the Kerr-Newman Black hole. We close with some observations about the “black holes have no hair” theorem, and our problem. Citing some recent suppositions that this “theorem” may not be completely true and how that may relate to our experimental situation. We close with observations from Haijicek, 2008 as which may be pertinent to Quantization of Gravity. Furthermore as an answer to questions raised by a referee, we will have a final statement as to how this problem is for a real black hole being induced, and answering his questions in his review, which will be included in a final appendix to this paper. The main issue which is now to avoid the black hole bomb effect which would entail an explosion of a small black hole in a laboratory. Furthermore as an answer to questions raised by a referee, we will have a final statement as to how this problem is for a real black hole being induced, and answering his questions in his review, which will be included in a final appendix to this paper. In all, the main end result is to try to avoid the so called black hole bomb effect, where a mini black hole would explode in a laboratory setting within say 10^?16 or so seconds, i.e. the idea would be to have a reasonably stable configuration within put laser energy, but a small mass, and to do it over hopefully 10^15 or more times longer than the 10^?16 seconds where the mini black hole would quickly evaporate. I.e. a duration of say up to 10^?1 seconds which would provide a base line as to astrophysical modeling of a Kerr-Newman black hole. 展开更多
关键词 KERR NEWMAN Black Hole high-frequency Gravitational waves (HGW) CAUSAL DISCONTINUITY
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Does a Restricted Quintic Polynomial in Minimum Time Step (Planck Time Interval) Being Solvable in a Galois Theory Sense Affect the Closing of a Wormhole Throat if (Kaluza Klein Theory) Is Assumed and Impact Admissible Gravitational Wave Polarization?
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作者 Andrew Walcott Beckwith 《Journal of High Energy Physics, Gravitation and Cosmology》 2019年第3期683-710,共28页
In a prior paper, the d = 1 to d = 7 sense of AdS/CFT solutions were described in general whereas we did not introduce commentary as to GW polarization of gravitational radiation from a worm hole. We will discuss GW p... In a prior paper, the d = 1 to d = 7 sense of AdS/CFT solutions were described in general whereas we did not introduce commentary as to GW polarization of gravitational radiation from a worm hole. We will discuss GW polarization, for d = 1 and in addition say concrete facts as to the strength of the GW radiation, and admissible frequencies. First off, the term Δt is for the smallest unit of time step. Note that in the small Δt limit for d = 1 we avoid any imaginary time no matter what the sign of Ttemp is. And when d = 1 in order to have any solvability one would need X = Δt assumed to be infinitesimal. To first approximation, we set X = Δt as being of Planck time, 10-31 or so seconds, in duration. 展开更多
关键词 Kerr NEWMAN Black Hole high-frequency Gravitational waves (HGW) SOLVABLE Quintic Equations WORMHOLES
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小针刀疗法联合超声引导下冲击波治疗中风后肢体痉挛的效果及对患者肌张力、运动功能的影响 被引量:2
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作者 廖越 刘继生 +2 位作者 兰彩虹 刘明辉 吴宝贤 《中国当代医药》 CAS 2023年第4期149-152,共4页
目的探讨小针刀疗法联合超声引导下冲击波治疗中风后肢体痉挛的效果及对患者肌张力、运动功能的影响。方法选取2021年10月至2022年5月贵州中医药大学第二附属医院针灸康复科的60例中风后肢体痉挛患者作为研究对象,采用随机数字表法将其... 目的探讨小针刀疗法联合超声引导下冲击波治疗中风后肢体痉挛的效果及对患者肌张力、运动功能的影响。方法选取2021年10月至2022年5月贵州中医药大学第二附属医院针灸康复科的60例中风后肢体痉挛患者作为研究对象,采用随机数字表法将其分成对照组(n=30)和观察组(n=30)。对照组患者采用小针刀疗法,观察组患者采用小针刀疗法联合超声引导下冲击波治疗。比较两组患者的疗效、肌张力及运动功能。结果观察组的治疗总有效率高于对照组,差异有统计学意义(P<0.05)。两组治疗前的改良Ashworth评分(MAS)比较,差异无统计学意义(P>0.05);两组治疗后的MAS分值均低于治疗前,差异有统计学意义(P<0.05);观察组治疗21 d后的MAS分值低于对照组,差异有统计学意义(P<0.05)。两组治疗前的简式肢体运动功能(FMA)评分比较,差异无统计学意义(P>0.05);两组治疗后的FMA评分均高于治疗前,差异有统计学意义(P<0.05);观察组治疗21 d后的FMA分值高于对照组,差异有统计学意义(P<0.05)。结论联合小针刀以及超声引导下冲击波对中风后肢体痉挛进行治疗,能够有效改善患者的肌张力、运动功能,疗效显著。 展开更多
关键词 小针刀 超声 冲击波 中风后肢体痉挛 疗效 肌张力 运动功能
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