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This article aims to investigate a selected number of liquid hydrogen storage tank parameters in a turboelectric distributed propulsion concept.

In this research study, tank structure, tank geometry, tank materials and additional physical phenomenon such as hydrogen boil-off and permeation are considered. A parametric analysis of different insulation foams is also performed throughout the design process of a lightweight liquid hydrogen storage tank.

Based on the mass of boil-off and foam weight, phenolic foam exhibited better characteristics amongst the five foam insulation materials considered in this particular study.

Liquid hydrogen occupies 4.2 times the volume of jet fuel for the same amount of energy. This suggests that a notable tank size is expected. Nonetheless, as jet fuel weighs 2.9 times more than liquid hydrogen for the same amount of energy, this reduced weight aspect partly compensates for the increased tank size.

In this article, potential insulation materials for liquid hydrogen storage tanks are highlighted and compared utilizing a presented methodology.

Some areas of the apparel industry, such as folding and sewing, are still labor intensive. The purpose of this paper is to present a new fuzzy visual servoing strategy for the folding of fabric strips by robotic manipulators.

Three stages of the folding task are distinguished experimentally, the initial laying, the true folding, and the final laying. An indirect visual servoing fuzzy system, employing two cameras, is developed to guide the robot along each of the stages.

The proposed scheme manages to successfully fold some of the tested materials. The experimental results are promising and well within the limitations posed by both the employed equipment and the nature of the handled materials.

This study is limited to rectangular strips of fabrics and does not consider the speed of the process.

The resulting system provides a stepping stone for the introduction of automation to currently labor‐intensive areas of the apparel industry.

The separate folding stages reduce the complexity of the overall system and the introduced visually extracted features allow a closer monitoring of the process.

Boundary layer ingestion (BLI) is one of the probable noteworthy features of distributed propulsion configuration (DPC). Because of BLI, strong coupling effects are generated between the aerodynamics and propulsion system of aircraft, leading to the specific lift and drag aerodynamic characteristics. This paper aims to propose a model-based comprehensive analysis method to investigate this unique aerodynamic.

To investigate this unique aerodynamics, a model-based comprehensive analysis method is proposed. This method uses a detailed mathematical model of the distributed propulsion system to provide the essential boundary conditions and guarantee the accuracy of calculation results. Then a synthetic three-dimensional computational model is developed to analyze the effects of BLI on the lift and drag aerodynamic characteristics.

Subsequently, detailed computational analyses are conducted at different flight states, and the regularities under various flight altitudes and velocities are revealed. Computational results demonstrate that BLI can improve the lift to drag ratio evidently and enable a great performance potentiality.

The general analysis method and useful regularities have reference value to DPC aircraft and other similar aircrafts.

This paper proposed a DPS model-based comprehensive analysis method of BLI benefit on aerodynamics for DPC aircraft, and the unique aerodynamics of this new configuration under various flight altitudes and velocities was revealed.