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Главным направлением развития современной коммерческой авиации является не только повышение безопасности и топливной эффективности самолeтов, но и снижение воздействия на окружающую среду, особенно по допустимому шуму на местности. Одной из идей является перенос силовой установки на верхнюю поверхность крыла для экранирования шума двигателя крылом. Такое решение может приводить к усугублению неблагоприятных явлений трансзвуковой интерференции между элементами планера, вынуждая снижать крейсерскую скорость до числа Маха $\mathrm{M}=0.7$-$0.75$, вместо наиболее распространенной $\mathrm{M}=0.78$-$0.8$. Решение проблемы интерференции на крейсерском режиме для малошумных компоновок требует усовершенствования устоявшейся методики проектирования. В данной работе представлены исследования по методике проектирования аэродинамической компоновки малошумного самолета, имеющего две особенности: двигатели расположены над задней кромкой крыла, и само крыло имеет малую стреловидность $\chi_{1/4}\sim15^\circ$ с естественной ламинаризацией обтекания (ЕЛО), при сохранении крейсерского числа $\mathrm{M}=0.78$. Получено экспериментальное подтверждение реализуемости данной концепции.

When developing the country’s made peripheral docking assembly consistent with the International Docking System Standard a task arose concerning reduction of dimensions of the latch mechanisms that ensure the capture. The article describes the mode of operation of these mechanisms. Proposed is a procedure which makes it possible to choose such a layout of their joints in which the links are inside a given area during operation. A uniform LPτ-sequence is used to form various options of the joints layout. A criterion of maximum loads acting on the links is described. It is shown that the dimensions of the existing latch mechanism can be decreased only with an increase of the load-carrying capability of the links. The proposed procedure is part of a software tool computerizing the design of a new latch mechanism. Key words: spacecraft docking, peripheral docking assembly, latch mechanism, capture, LPτ-sequence.

The docking ring of an elastically adaptive docking mechanism on the initial contact signal is extended by spring-loaded mechanisms of the rods in order to improve capture conditions. In the process, it reaches a high velocity, which applies unacceptably high impact loads to the docking interface. This paper discusses an extension velocity limiter for the docking ring, its analytical model, and a brief procedure for calculating its parameters. It describes a simplified model for ring extension during initial contact, and a method for determining viscous friction coefficient of the ball-screw pair of the docking mechanism, which is a parameter in the model. It presents the procedure, results and comparison of simulations of the docking ring extension both with the use of the proposed retarder and without it. It is demonstrated that the use of the velocity limiter permits to meet the requirements of the International Standard for pulsed loads on the passive interface. The paper describes a design option for velocity limiter that has acceptable mass and dimensions. Keywords: spacecraft docking, elastically adaptive docking mechanism, retraction device, velocity limiter, mechanical governor

Tools necessary for quantum simulations of $1+1$ dimensional quantum chromodynamics are developed. When formulated in axial gauge and with two flavors of quarks, this system requires 12 qubits per spatial site with the gauge fields included via non-local interactions. Classical computations and D-Wave's quantum annealer Advantage are used to determine the hadronic spectrum, enabling a decomposition of the masses and a study of quark entanglement. Color edge states confined within a screening length of the end of the lattice are found. IBM's 7-qubit quantum computers, ibmq_jakarta and ibm_perth, are used to compute dynamics from the trivial vacuum in one-flavor QCD with one spatial site. More generally, the Hamiltonian and quantum circuits for time evolution of $1+1$ dimensional $SU(N_c)$ gauge theory with $N_f$ flavors of quarks are developed, and the resource requirements for large-scale quantum simulations are estimated., Comment: 53 pages, 29 figures. Typo fixed in v3

Studying QCD and other gauge theories on quantum hardware requires the preparation of physically interesting states. The Variational Quantum Eigensolver (VQE) provides a way of performing vacuum state preparation on quantum hardware. In this work, VQE is applied to pure SU(3) lattice Yang-Mills on a single plaquette and one dimensional plaquette chains. Bayesian optimization and gradient descent were investigated for performing the classical optimization. Ansatz states for plaquette chains are constructed in a scalable manner from smaller systems using domain decomposition and a stitching procedure analogous to the Density Matrix Renormalization Group (DMRG). Small examples are performed on IBM's superconducting Manila processor., Comment: 23 pages, 16 figures, 4 tables

Spacecraft docking is a controlled on-orbit mechanical assembly process realized using active and passive docking units. The docking mechanism of the active unit provides capture conditions, attenuation of active spacecraft approach energy, alignment and retraction of the docking units before their hard connection. A kinematical scheme of a new peripheral docking mechanism is considered in this paper. Instead of energy damping, it is based on energy accumulation using springs with controlled recoil blocking. The blocking is activated before docking and keeps the docking mechanism in its initial position. On the first contact signal, the blocking is switched off releasing the energy of compressed springs for quick forward moving of the docking ring and improving capture. The blocking is activated again after capture and approach energy is accumulated by the springs without returning to the mechanical system. Avoiding contacts of docking mechanism links between each other and with the docking unit body is important for peripheral mechanisms due to their design. A procedure for choosing parameters of an energy accumulator that allows attenuating a max permissible energy without link contacts and without exceeding the max permissible value of the axial interface load is considered here. Key words: spacecraft, docking, docking mechanism.

Experimental investigation of aeroacoustic and aerodynamic characteristics of a largescale semi-span wing model in approach configuration has been performed in aeroacoustic wind tunnel DNW-NWB. Effect of Reynolds number on airframe noise, as well as noise reduction concepts for slat noise have been studied. A comparison of the aerodynamic results obtained in DNW-NWB for chevron slat and reference slat configuration is also provided.