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Simultaneous intermetallics suppression and residual-stress relaxation of heat-resistant Nb-interlayer-inserted Ti-6Al-4V/Si_(3)N_(4)joints via one-step transient liquid phase bonding and brazing

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Journal of Materials Science & Technology 2023年第8期139卷 79-91页

作者： Fei Shen Ong Hirobumi Tobe Eiichi Sato Institute of space and Astronautical Science Japan Aerospace Exploration Agency3-1-1 YoshinodaiChuoSagamihara 252-5210Japan Department of Materials Engineering Graduate School of EngineeringThe University of Tokyo7-3-1 HongoBunkyoTokyo 113-8656Japan

This work has successfully proposed a solution to produce robust Nb-interlayer-inserted Ti-6Al-4V/Si_(3)N_(4)joints optimized for a maximum operating temperature of 873 K;transient liquid phase bonding(TLPB)of Ti-6Al-4V/Nb side was carried out with Cu and Ni fillers to suppress brittle intermetallic compounds(IMCs),whereas brazing of Nb/Si_(3)N_(4)side was performed using a highly ductile Ti-added Ag-rich filler for effective residual-stress relaxation.A sound yet simple one-step bonding process inc.rporating simul-taneous TLPB and brazing was achieved with a relatively short holding time of 10 min at 1213 *** of Ti-6Al-4V/Nb side with Cu and Ni foils of 2-μm-thick each as a laminated filler suppressed brittle Ti-based IMCs and developed a homogenized microstructure consisting mainly of(α+β)-Ti via isothermal ***,brazing of Nb/Si_(3)N_(4)side with 100-μm-thick SILVER-ABA filler(92.75Ag-5Cu-1Al-1.25Ti mass%)foil enhanced interfacial bonding with sufficient total Ti content and accommodated residual stress better than conventional eutectic Ag-Cu-based fillers,and it was verified by finite element analysis with consideration of materials’temperature-dependent elasto-plastic *** joints with a bonding area of 10 mm×10 mm were tested via symmetrical four-point bending from room temper-ature(RT)to 873 K fractured from Nb/Si_(3)N_(4)*** re-heating the joints from RT to 673 K,frac-ture initiation gradually shifted from Si_(3)N_(4)towards interfacial-compounds/Si_(3)N_(4)interface and bending strengths maintained∼220 MPa as weakening of SILVER-ABA filler was compensated by residual-stress relaxation in Si_(3)N_(4).When tested at 873 K,joints fractured mainly across the Ag-rich solid solution in a ductile manner and bending strength degraded by∼20%to 171 MPa as weakening of SILVER-ABA filler dominated.

关键词： Transient liquid phase bonding Brazing Ceramics Residual stress Finite element analysis

Airglow simulation based on the Atmospheric Ultraviolet Radiance Integrated Code of 2012

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Science China Earth Sciences 2016年第11期59卷 425-435页

作者： WANG HouMao WANG YongMei National space Science Center Chinese Academy of Sciences College of Earth Science University of Chinese Academy of Sciences

The Atmospheric Ultraviolet Radiance Integrated Code(AURIC) is a software package developed by Computational Physics, inc.(CPI) under the sponsorship of the Air Force Phillips Laboratory/Geophysics Directorate(PL/GP)(currently the Air Force Research Laboratory) for middle and upper atmospheric radiance modeling from the far ultraviolet to the near infrared. The AURIC has been considered as a general model for the radiative transfer simulation of airglow. Based on the theory of MODerate resolution atmospheric TRANsmission(MODTRAN), the AURIC extends calculation to altitudes above 100 km and the wavelength down to 80 nm. A package of AURIC v1.2 was released in 2002, which can be used for single-point simulation from 1947 to 1999. It means that the model is not suitable for atmospheric simulation of large datasets or for atmospheric parameters retrieval from amount of satellite measurements. In this paper, AURIC v1.2 is upgraded to AURIC-2012 based on MATLAB with improvements for modules of the Geomagnetic Parameter(GEOPARM), Atmosphere neutral composition(ATOMS), and Ionospheric electron density(IONOS). The improved AURIC can be used for global automatic airglow simulation and also for automatic retrieval of atmospheric compositions from satellite global observations, such as O/N2 and electron density etc. Besides, the model supplies possibilities for further improvement of airglow radiative mechanism and for substitution of other modules. Based on the AURIC-2012, Limb Column Emission Intensity(L-CEI) and Volume Emission Rate(VER) are calculated. For validation, the results were compared with measurements of the Global Ultraviolet Imager(GUVI) and TIMED Doppler Interferometer(TIDI), respectively. The averaged relative errors of L-CEI and VER at peak altitude are both within 20%. Finally, L-CEI varying with latitude, altitude, solar activity, and geomagnetic activity is simulated, and the distribution characteristics of the simulation and their influencing factors are

关键词：高层大气大气模拟紫外辐射美国空军研究实验室代码集成辐射传输模型 MODTRAN

5D World-Universe Model. Gravitation

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Journal of High Energy Physics, Gravitation and Cosmology 2016年第3期2卷 328-343页

作者： Vladimir S. Netchitailo Biolase inc. Irvine CA USA

5D World-Universe Model is based on the decisive role of the Medium of the World composed of massive particles: protons, electrons, photons, neutrinos, and dark matter particles. In this manuscript we discuss different aspects of the gravitation: measured values of the Newtonian parameter of Gravitation and different Gravitational effects (gravitational lensing, cosmological redshift, gravitational deflection of light and gravitational refraction, proposed in the present paper). We show inter-connectivity of all cosmological parameters and provide a mathematical framework that allows direct calculation of them based on the value of the gravitational parameter. We analyze the difference between Electromagnetism and Gravitoelectromagnetism and make a conclusion about the mandatory existence of the Medium of the World. This paper aligns the World-Universe Model with the Le Sage’s theory of gravitation and makes a deduction on Gravity, space and Time be emergent phenomena.

关键词： 5D World-Universe Model Newtonian Parameter of Gravitation Le Sage’s Gravity Cosmic Neutrino Background Gravitoelectromagnetism Medium of the World Cosmological Parameters Emergent Phenomena

LoSI: Large Scale Location Inference Through FM Signal Integration and Estimation

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Big Data Mining and Analytics 2019年第4期2卷 319-348页

作者： Tathagata Mukherjee Piyush Kumar Debdeep Pati Erik Blasch Eduardo Pasiliao Liqin Xu Department of Computer Science University of Alabama in HuntsvilleHuntsvilleAL 35806USA CompGeom inc. TallahasseeFL 32311USA Department of Statistics Texas A&M UniversityCollege StationTX 77843USA Air Force Research Laboratory RomeNY 13441USA Air Force Research Laboratory ShalimarFL 32579USA CompGeom inc. TallahasseeFL 32579USA

In this paper we present a large scale, passive positioning system that can be used for approximate localization in Global Positioning System(GPS) denied/spoofed environments. This system can be used for detecting GPS spoofing as well as for initial position estimation for input to other GPS free positioning and navigation systems like Terrain Contour Matching(TERCOM). Our Location inference through Frequency Modulation(FM)Signal Integration and estimation(LoSI) system is based on broadcast FM radio signals and uses Received Signal Strength Indicator(RSSI) obtained using a Software Defined Radio(SDR). The RSSI thus obtained is used for indexing into an estimated model of expected FM spectrum for the entire United States. We show that with the hardware for data acquisition, a single point resolution of around 3 miles and associated algorithms, we are capable of positioning with errors as low as a single pixel(more precisely around 0.12 mile). The algorithm uses a largescale model estimation phase that computes the expected FM spectrum in small rectangular cells(realized using geohashes) across the Contiguous United States(CONUS). We define and use Dominant Channel Descriptor(DCD) features, which can be used for positioning using time varying models. Finally we use an algorithm based on Euclidean nearest neighbors in the DCD feature space for position estimation. The system first runs a DCD feature detector on the observed spectrum and then solves a subset query formulation to find Inference Candidates(IC).Finally, it uses a simple Euclidean nearest neighbor search on the ICs to localize the observation. We report results on 1500 points across Florida using data and model estimates from 2015 and 2017. We also provide a Bayesian decision theoretic justification for the nearest neighbor search.

关键词： Global Positioning System(GPS)-free positioning Frequency Modulation(FM) radio signals of opportunity nearest neighbor search

Measurement of sub-fm/Hz^(1/2) displacement spectral densities in ultrahigh-Q single-crystal microcavities with hertz-level lasers

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Photonics Research 2022年第5期10卷 1202-1209页

作者： YOON-SOO JANG JINKANG LIM WENTING WANG SEUNG-WOO KIM ANATOLIY SAVCHENKOV ANDREY BMATSKO CHEE WEI WONG Fang Lu Mesoscopic Optics and Quantum Electronics Laboratory University of CaliforniaLos AngelesCalifornia 90095USA Division of Physical Metrology Korea Research Institute of Standards and Science(KRISS)Daejeon 34113Republic of Korea CACI-LGS Labs Florham ParkNew Jersey 07932USA Department of Mechanical Engineering Korea Advanced Institute of Science and Technology(KAIST)Daejeon 34141Republic of Korea OEwaves inc. PasadenaCalifornia 91107USA Jet Propulsion Laboratory California Institute of TechnologyPasadenaCalifornia 91109USA

Tracing a resonance frequency of a high quality factor(Q)optical cavity facilitates subpicometer displacement measurements of the optical cavity via Pound-Drever-Hall(PDH)locking scheme,tightly synchronizing a laser frequency to the optical *** we present observations of subfemtometer displacements on a ultrahigh-Q single-crystal MgF_(2)whispering-gallery-mode microcavity by frequency synchronization between a 1 Hz cavity-stabilized laser and a resonance of the MgF_(2) cavity using PDH laser-cavity *** characterize not only the displacement spectral density of the microcavity with a sensitivity of 1.5×10^(-16) m/Hz^(1/2) over the Fourier offset frequency ranging from 15 mHz to 100 kHz but also a 1.77 nm displacement fluctuation of the microcavity over 4500 *** measurement capability not only supports the analysis of integrated thermodynamical and technical cavity noise but allows for minute displacement measurements using laser-cavity locking for ultraprecise positioning,metrology,and sensing.

关键词： synchronization displacement cavity

Optimizing the PMCC Algorithm for Infrasound and Seismic Nuclear Treaty Monitoring

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Open Journal of Acoustics 2014年第4期4卷 204-213页

作者： Anthony M. Runco Jr. James A. Louthain Dean A. Clauter space and Missile systems Center United States Air Force Los Angeles Air Force Base El Segundo CA USA Leidos inc. Beavercreek OH USA Air Force Technical Applications Center United States Air Force Patrick Air Force Base Cocoa Beach FL USA

We introduce novel methods to determine optimum detection thresholds for the Progressive Multi-Channel Correlation (PMCC) algorithm used by the International Data Centre (IDC) to perform infrasound and seismic station-level nuclear-event detection. Receiver Operating Characteristic (ROC) curve analysis is used with real ground truth data to determine the trade-off between the probability of detection (PD) and the false alarm rate (FAR) at various detection thresholds. Further, statistical detection theory via maximum a posteriori and Bayes cost approaches is used to determine station-level optimum “family” size thresholds before detections should be considered for network-level processing. These threshold-determining methods are extensible for family-characterizing statistics other than “size,” such as a family’s collective F-statistic or signal-to-noise ratio (SNR). Therefore, the reliability of analysts’ decisions as to whether families should be preserved for network-level processing can only benefit from access to multiple, independent, optimum decision thresholds based upon size, F-statistic, SNR, etc.

关键词： Progressive Multi-Channel Correlation PMCC Infrasound Nuclear Treaty Monitoring Detection Optimization

A Modal Identification Algorithm Combining Blind Source Separation and State space Realization

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Journal of Signal and Information Processing 2013年第2期4卷 173-185页

作者： Scot McNeill Stress Engineering Services Inc. Houston USA

A modal identification algorithm is developed, combining techniques from Second Order Blind Source Separation (SOBSS) and State space Realization (SSR) theory. In this hybrid algorithm, a set of correlation matrices is generated using time-shifted, analytic data and assembled into several Hankel matrices. Dissimilar left and right matrices are found, which diagonalize the set of nonhermetian Hankel matrices. The complex-valued modal matrix is obtained from this decomposition. The modal responses, modal auto-correlation functions and discrete-time plant matrix (in state space modal form) are subsequently identified. System eigenvalues are computed from the plant matrix to obtain the natural frequencies and modal fractions of critical damping. Joint Approximate Diagonalization (JAD) of the Hankel matrices enables the under determined (more modes than sensors) problem to be effectively treated without restrictions on the number of sensors required. Because the analytic signal is used, the redundant complex conjugate pairs are eliminated, reducing the system order (number of modes) to be identified half. This enables smaller Hankel matrix sizes and reduced computational effort. The modal auto-correlation functions provide an expedient means of screening out spurious computational modes or modes corresponding to noise sources, eliminating the need for a consistency diagram. In addition, the reduction in the number of modes enables the modal responses to be identified when there are at least as many sensors as independent (not inc.uding conjugate pairs) modes. A further benefit of the algorithm is that identification of dissimilar left and right diagonalizers preclude the need for windowing of the analytic data. The effectiveness of the new modal identification method is demonstrated using vibration data from a 6 DOF simulation, 4-story building simulation and the Heritage court tower building.

关键词： Modal Identification Blind Source Separation State space Realization Analytic Signal Complex Modes

Gravitational and Anti-Gravitational Applications

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International Journal of Geosciences 2017年第4期8卷 471-493页

作者： Roger Ellman The-Origin Foundation Inc. Santa Rosa USA

Because gravitation operates by a flow from the attracting object acting on the attracted object as shown in the prior papers Connecting Newton’s G With the Rest of Physics-Modern Newtonian Gravitation Resolving the Problem of “Big G’s” Value and The Mechanics of Gravitation-What It Is;How It Operates, it is now possible to partially deflect gravitation away from an object so that the gravitational attraction on the object is reduced. That effect makes it possible to extract energy from the gravitational field, which makes the generation of gravito-electric power technologically feasible. Such plants would be similar to hydro-electric plants and would have their advantages of not needing fuel and not polluting the environment. Physically, the action of deflecting away gravitational attraction, which of course is directed toward the gravitation source, produces an equal but opposite reaction on the mechanism that produces the deflection of the gravitational action [the deflector], a reaction directed away from the gravitation source. The result is the combination of reducing the gravitational attractive acceleration of the object toward the gravitation source plus the introducing of a reactive acceleration on the object in the direction away from the gravitation source. Such a deflector, engineered to enable controlled adjustment of the amount and the direction of its action, could provide for a spacecraft both launch levitation and deep space travel acceleration. It could provide both levitation and horizontal motion for a flying vehicle over a planet surface. This technology, which uses readily abundantly available materials and techniques, is ready now for research and engineering refinement.

关键词： Gravitation Electric Power Plants Gravitational Levitation

Two Strong Simple Proofs That All Doppler Shifts (inc.uding the Axial) Impact Observed Time, and All the Transverse Does

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Journal of High Energy Physics, Gravitation and Cosmology 2020年第4期6卷 765-773页

作者： Samuel Lewis Reich Engineering Tribco Inc. Cleveland OH USA

The first proof (Sections 2 - 4), applies Doppler shifts to the Fourier time sine series. It shows if K = f'/f (frequency ratio of the shift, f' the shifted frequency), then the value of the series at time = t occurs in the shifted series at time = t/K. That is because in each harmonic the sin(f't) and cos(f't) became sin(Kft) and cos(Kft). The original series could be the number of photons in area of a beam with encoded information. Therefore the number of observed photons and information has the same resultant Doppler shift as frequency. Resultant is total effect of axial, transverse and gravitational shifts. Mass and energy of light do not have the same Doppler shift which may indicate missing parts that Doppler shift and that mass traveling at the speed of light is different from other mass and energy. The second proof (Section 5) the vector equations of space time require observed time to have 3 dimensions if the speed of light is constant in all directions, but the Doppler shift in each direction is not the same. The blue shift (compression) of time has paradoxes. If time has many dimensions, that would solve the paradoxes, but break conservation laws. No solution of that is given here. It is not expected that radical a solution will have any followers.

关键词： Doppler Relativity Aether Fourier Series Time Travel Paradox Invariants