A review on simulation-based optimization methods applied to building performance analysis

The status of experimental tests of general relativity and of theoretical frameworks for analysing them are reviewed. Einstein's equivalence principle (EEP) is well supported by experiments such as the Eotvos experiment, tests of special relativity, and the gravitational redshift experiment. Future tests of EEP and of the inverse square law will search for new interactions arising from unification or quantum gravity. Tests of general relativity at the post-Newtonian level have reached high precision, including the light deflection, the Shapiro time delay, the perihelion advance of Mercury, and the Nordtvedt effect in lunar motion. Gravitational wave damping has been detected to half a percent using the binary pulsar, and new binary pulsar systems may yield further improvements. When direct observation of gravitational radiation from astrophysical sources begins, new tests of general relativity will be possible.

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The Confrontation between General Relativity and Experiment

Review and comparison of active space debris capturing and removal methods

Review of uncertainty-based multidisciplinary design optimization methods for aerospace vehicles

Statistical models in engineering , Statistical models in engineering , مرکز فناوری اطلاعات و اطلاع رسانی کشاورزی

Statistical Models in Engineering

Survey of worldwide pico- and nanosatellite missions, distributions and subsystem technology

a = positive parameter atx aty atz T = linear acceleration due to the tether tension, m · s−2 ax ay az T = linear acceleration of the gripper’s thruster force, m · s−2 C k = matrix in coordinated desaturation controller d = position vector of the capture position, m Fl = tether tension, N I = inertia matrix of the combination, kg · m I0 = nominal value of combination’s inertia matrix, kg · m Kξ = positive-definite design matrix k2 = positive-definite design matrix m = mass of tethered space robot–target combination, kg Oxlylzl = space tether frame Oxpypzp = space platform orbital frame Oxtytzt = combination orbital frame Ox 0 t y 0 t z 0 t = combination body frame P = positive-definite design matrix R = transformationmatrix from platform orbital frame to combination body frame S k = constant positive weighting matrix Tl = tether control torque, Nm x y z T = centroid position of the combination in the platform orbital frame, m ΔI = inertia matrix uncertainty, kg · m e = positive parameter λ k = Lagrange multiplier λL = upper bound of disturbance λL = estimation values of disturbance μ = positive design parameter ξ = state of the auxiliary design system σ = modified Rodrigues parameters σd = desired modified Rodrigues parameters τ k = vector of optimal thruster force and tether tension τc = control torque of the combination, N · m τd = disturbing torques, N · m τt = control torque of the thruster, N · m τl = control torque of the tether, N · m ω = absolute angular velocity of the combination, rad · s−1 ωd = desired angular velocity of the combination, rad · s−1

Adaptive Postcapture Backstepping Control for Tumbling Tethered Space Robot–Target Combination

In this paper, we systematically introduce a novel geostationary orbit (GEO) space debris removal system called dexterous tethered space robot (DTSR). The DTSR has three notable characteristics: dexterity, lightweight, and cost effectiveness. We first describe the system's design and a typical mission scenario, and then present its two core technologies (vision-based pose measurement and coordinated controller design) in detail. Finally, we present the extensive simulations and ground semiphysical experiments to verify that the DTSR is a feasible solution to effectively remove the GEO space debris.

Jian Guo

Papers

Review and comparison of active space debris capturing and removal methods

Review of uncertainty-based multidisciplinary design optimization methods for aerospace vehicles

Survey of worldwide pico- and nanosatellite missions, distributions and subsystem technology

Adaptive Postcapture Backstepping Control for Tumbling Tethered Space Robot–Target Combination

Dexterous Tethered Space Robot: Design, Measurement, Control, and Experiment