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Helical coil electromagnetic launchers (HEMLs) using motion-induced commutation strategy solve the problem of synchronization control perfectly. HEMLs can meet the requirements of multiple applications such as the electromagnetic catapult, electromagnetic mortar and high-velocity coilgun. The trade-off between the velocity and efficiency is an important basis for these different applications. To optimize such objectives before actual design, the purpose of this paper is to focus on the efficient and flexible calculation model and algorithm. A novel structure of HEML is proposed after the transient simulation by this algorithm, which can improve the energy conversion efficiency and suppress the muzzle arc without affecting the velocity too much.

The equivalent circuit model of the launcher is established and the governing equations are derived. A combination of the four-stage Runge–Kutta method and the trapezoidal quadrature formula are used to solve the governing equations.

With smaller number of turns in the coils of HEML, the velocity is larger and the efficiency is lower. The non-uniform HEML is an effective option to improve the energy conversion efficiency and to suppress the muzzle arc with almost the same muzzle velocity as the conventional HEML.

The paper presents a common model and a flexible fast numerical method which can be used in multi-objective optimization of HEMLs such as the genetic algorithm. A new structure of the non-uniform HEML is proposed to improve the energy conversion efficiency and to suppress the muzzle arc of the launcher.

The purpose of this paper is to improve the D* algorithm which has been used usually in robotics for mobile robot navigation in unknown or dynamic environments.

First, the model of 2D workspace with some obstacles is expressed in regularity grids. The optimal path is planned by using the improved D* algorithm by searching in the neighbor grid cells in 16 directions. It makes the robot that the smallest turning angle drops to π/8. The robot moving angle discrete precision is raised and the unnecessary cost of path planning is reduced so the robot motion path is smoother. Then, the improved D* algorithm is simulated in MOBOTSIM software environment and is tested by the WiRobotX80 mobile robot.

To search in the neighbor grid cells in 16 directions instead of eight directions by using D* algorithms for path planning.

The map should be expressed in regularity grids.

The improved D* algorithm is effective and it can result in a higher quality path than the conventional D* algorithm at the same map environment.

The Qingcheng County, where the ancient city wall is located, has rich regional cultural heritage. This ancient city wall is an important symbol for exhibiting the regional historical culture of Qingcheng. However, urban expansionary construction activities, environment chaos, and other issues have led to the destruction of the main part of the Qingcheng Ancient City Wall. Previous strategies for historical and cultural heritage Preservation planning emphasize rigidity and disregard resilience in protecting cultural heritage and the environment. On the basis of an analysis of the built environment of the Qingcheng Ancient City Wall, this study gains insights into the three aspects, namely, land use, road traffic, and municipal and disaster prevention in frastructure of the old city proper where the ancient city wall is located. A planning strategy that integrates an ordered control of land development, highly efficient and compound road traffic, synergetic municipal administration, and sound disaster-preventing infrastructure is formed according to cognitive results.

A review of 67 articles in the indoor environmental quality (IEQ) literature published from 2010 to 2020 reveals that none of prior studies have determined the IEQ of physical retailers and its impact on consumers. To fill such a gap, this study investigates the influence of physical retailers' IEQ on consumer purchase intention. The mediating roles of hedonic experience and perceived brand value (PBV) in this relationship are also determined. Furthermore, the moderating effect of perceived service quality (PSQ) on the link between physical retailers' IEQ and PBV is clarified in this study.

This study uses structural equation modeling (SEM) to analyze a sample data of 996 consumers in China.

Results show that physical retailers' IEQ has a positive impact on consumer purchase intention. Hedonic experience mediates the link between IEQ and purchase intention. PBV also mediates the relationship between IEQ and purchase intention and that between hedonic experience and purchase intention. In addition, PSQ moderates the relationship between IEQ and PBV.

To the best of the authors’ knowledge, this study is the first to determine the impact of IEQ on consumers in the physical retailer context. Specifically, this study enriches our knowledge about the relationship between physical retailers' IEQ and consumer purchase intention with the mediating and moderating mechanisms of hedonic experience, PBV and PSQ. The findings fill the research gaps in the IEQ literature that has ignored the impact of IEQ on consumers' perception and behavioral intention in the physical retailer context. Furthermore, this research provides evidence for retailer managers to understand and improve physical stores' IEQ.

This paper aims to present recently published resources on library instruction and information literacy, providing an introductory overview and a selected annotated bibliography of publications covering various library types, study populations and research contexts.

This paper introduces and annotates English-language periodical articles, monographs, dissertations, reports and other materials on library instruction and information literacy published in 2019.

The paper provides a brief description of all 370 sources and highlights sources that contain unique or significant scholarly contributions.

The information may be used by librarians, researchers and anyone interested as a quick and comprehensive reference to literature on library instruction and information literacy.