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In the case of the given design variables and constraint functions, this paper is concerned with the rapid overall parameters design of trajectory, propulsion and aerodynamics for long-range ballistic missiles based on the index of the minimum take-off mass. In contrast to the traditional subsystem independent design, this paper adopts the research idea of the combination of the subsystem independent design and the multisystem integration design. Firstly, the trajectory, propulsion and aerodynamics of the subsystem are separately designed by the engineering design, including the design of the minimum energy trajectory, the computation of propulsion system parameters, and the calculation of aerodynamic coefficient and dynamic derivative of the missile by employing the software of missile DATCOM. Then, the uniform design method is used to simplify the constraint conditions and the design variables through the integration design, and the accurate design of the optimized variables would be accomplished by adopting the uniform particle swarm optimization (PSO) algorithm. Finally, the automation design software is written for the three-stage solid ballistic missile. The take-off mass of 29 850 kg is derived by the subsystem independent design, and 20 constraints are reduced by employing the uniform design on the basis of 29 design variables and 32 constraints, and the take-off mass is dropped by 1 850 kg by applying the combination of the uniform design and PSO. The simulation results demonstrate the effectiveness and feasibility of the proposed hybrid optimization technique. [ABSTRACT FROM AUTHOR]

• An initially study on the estimation of distinct contents with local differential privacy. • A novel problem formulation maximizing the probability all existing contents identified by the data requestor. • Two novel heuristics algorithms for the bandwidth assignment in different scenarios. • Numerical experiments towards real-world dataset demonstrating the performances of proposed framework. Human beings with smart devices have dramatically facilitated the knowledge acquisition in ubiquitous computing systems. However, the collected contents also severely threat the security and privacy for individuals, as these contents achieve a fine-grained coverage of one's behaviors and movements. Local differential privacy, as one of the widely accepted properties, enables individuals to contribute to data collection while remaining indistinguishable against adversaries. However, existing solutions and mechanisms fail to capture the contents with relatively low frequency, e.g. , the temperature in local regions visited by very few people. Therefore, this work proposes a novel framework for distinct content estimation under local differential privacy. We propose a hash function and random response based framework for the estimation. The framework allows individuals in the ubiquitous computing system to participate with flexible bandwidth, and properly assigns the given bandwidth to improve estimated results. We prove the optimization problem of assignment in our framework to be NP-complete, and provides an effective heuristic algorithm. Our framework is also proved to guarantee an unbiased estimation for distinct contents, and achieves local differential privacy for users. Meanwhile, we also propose a randomized algorithm designed for more general cases, where the preposed knowledge for the first algorithm is unavailable. Finally, we evaluate both algorithms on real world datasets, and the results reveal that our algorithms outperform existing methods. [ABSTRACT FROM AUTHOR]

The event generator BEEC (Yang et al. (2013) [11]) was devoted to the simulation of heavy quarkonium production at an unpolarized electron-positron collider. We upgraded it here by adding the generation of quarkonium with polarized electron and positron beams. In addition, the production of color-singlet 2 S -wave states were included. Several future electron-positron colliders with high luminosity have been under discussion in the past decade. Especially, their possibility of producing polarized beams is important for providing more insights into the underlying physics. This upgraded version offers a useful tool for the feasibility study on quarkonium from the experimental side. Program title: BEEC version 2.0 CPC Library link to program files: https://doi.org/10.17632/bvtwwm22tj.1 Licensing provisions: GNU General Public License 3 Programming language: FORTRAN 77/90 Journal Reference of previous version: Comput. Phys. Commun. 184 (2013) 2848 Does the new version supersede the previous version?: Yes Reasons for the new version: The proposed electron-positron colliders could possibly produce polarized beams, with which it would be helpful to provide more insights into the structure of the underlying physics in heavy quarkonium. Thus, it is essential to simulate the quarkonium production through polarized beams. In addition, the B c (2 S) state attracted more and more interests since its discovery, which makes it necessary to produce the 2 S -wave excited states. Summary of revisions: Two polarized amplitudes of leptonic scattering are computed theoretically. The relevant codes of the formula are included in BEEC2.0. Meanwhile, new parameters for the 2 S -excited states are also included. Nature of problem: Although PYTHIA can generate events for many processes, a dedicated event generator is also necessary. Especially, PYTHIA does not internally produce events with polarized beams. BEEC is implemented into PYTHIA as an external process for simulating heavy quarkonium events with high efficiency. Further hadronization and decay simulation can be done by using PYTHIA subroutine. Solution method: Two projection operators are used to calculate the polarized leptonic scattering amplitudes with the help of improved trace technology [1,2]. The code with option can generate events through unpolarized and polarized initial beams. In addition to the (Q Q ′ ¯)-quarkonium (Q , Q ′ = b , c) in color-singlet 1 S -wave states, 1 P -wave states, and the color-octet 1 S -wave states in the last version, BEEC 2.0 also deal with the production of 2 S -wave excited states within the framework of non-relativistic QCD [3]. Additional comments including restrictions and unusual features: About the running time, it depends on which option one chooses to match PYTHIA when generating the heavy quarkonium events. Typically, for the production of the S -wave quarkonium states, if setting IDWTUP=1 (unweighted events), then it takes about 21 minutes on a 3.22 GHz Apple M1 Pro Processor machine to generate 105 events; if setting IDWTUP=3 (weighted events), it takes only ∼5 minutes to generate 105 events. While for the production of the P -wave quarkonium states, the time will be almost one hundred times longer than the case of the S -wave quarkonium. [ABSTRACT FROM AUTHOR]

A novel multi-observer passive localization algorithm based on the weighted restricted total least square (WRTLS) is proposed to solve the bearings-only localization problem in the presence of observer position errors. Firstly, the unknown matrix perturbation information is utilized to form the WRTLS problem. Then, the corresponding constrained optimization problem is transformed into an unconstrained one, which is a generalized Rayleigh quotient minimization problem. Thus, the solution can be got through the generalized eigenvalue decomposition and requires no initial state guess process. Simulation results indicate that the proposed algorithm can approach the Cramer-Rao lower bound (CRLB), and the localization solution is asymptotically unbiased. [ABSTRACT FROM AUTHOR]

• Providing path-privacy for task acquisition in Mobile Crowdsensing Systems. • Supporting comprehensive flexible control on privacy preference. • A centralized algorithm for task assignment used by authentic third parties. • A distributed algorithm for task acquisition used by workers. • Outperforming baseline algorithms on the utility for platforms and workers. Mobile Crowdsensing is an emerging and promising sensing paradigm in which sensor data can be collected by mobile users equipped with smart devices. In Mobile Crowdsensing Systems (MCS), workers bid for location-based sensing tasks and get rewards from the platform. However, the bidding may leak workers' path privacy, which means the sensitive locations could be inferred from innocent locations along a path as workers continuously acquire for tasks. This privacy concern may significantly hinder the participation of workers. As a result, this paper designs a novel framework for adjustable path privacy preservation used for task acquisition in MCS. In this framework, workers are allowed to flexibly adjust their privacy preferences on the amount, sensitivity, and cost of private locations. Two algorithms are proposed to determine the set of bidding tasks for workers that jointly consider the privacy concerns and profits. The first algorithm processes in a centralized approach, which is proved to be rational, truthful and efficient. The second algorithm allows workers to decide their task acquisition locally, and guarantees the Nash equilibrium among workers. Both algorithms are validated via real-world dataset. The evaluation results demonstrate that the two proposed algorithms outperform baseline algorithms on both platform and worker sides. [ABSTRACT FROM AUTHOR]