Space Systems Research Articles

Patch Antenna Dielectrics Reduction by Topology Optimization and Radio Wave Characteristics

This research is aimed at exploring the potential for reducing the overall mass of large space structures on which space systems are supported. A key component of these systems comprises microwave arrayed antennas, which are distributed across the surface of the structure. Given that dielectric materials constitute a significant portion of the antenna mass, this study is primarily concerned with minimizing the mass of these antenna dielectrics. It is crucial to note that while reducing mass is a priority, the stiffness of the antenna system must be preserved, as it needs to adhere securely to the structure’s surface. To achieve this objective, we embark on a process of optimizing the topological distribution of the dielectric material. We investigate how this optimized configuration impacts the microwave characteristics of a patch antenna. Our approach involves conducting topological optimization while concurrently ensuring structural stiffness. Subsequently, we assess the influence of this optimized distribution on the antenna’s patterns and gains using different materials.

Contribution of Secondary Alpha Particles to Soft Error Rates in Space Systems

Contribution of Secondary Alpha Particles to Soft Error Rates in Space Systems

An approach to the global well-posedness of a coupled 3-dimensional Navier-Stokes-Darcy model with Beavers-Joseph-Saffman-Jones interface boundary condition

<abstract><p>This study focused on investigating the global well-posedness of a coupled Navier-Stokes-Darcy model with the Beavers-Joseph-Saffman-Jones interface boundary condition in the three-dimensional Euclidean space. By utilizing this approach, we successfully obtained the global strong solution of the system in the three-dimensional space. Furthermore, we demonstrated the exponential stability of this strong solution. The significance of such coupled systems lies in their pivotal role in the analysis of subsurface flow problems, particularly in the context of karst aquifers.</p></abstract>

Energy system and resource utilization in space: A state-of-the-art review

<p>Deep space exploration expands our understanding about the evolution history of solar system, while the future development heavily relies on the construction of energy systems and utilization of resources on the planet. This paper systematically reviewed the progress in the environmental control and construction technologies of space bases, extraterrestrial in situ resource utilization technology, energy systems, key technologies for planetary transportation platforms, and geological explorations. The current status, pros and cons of these technologies and systems are introduced and discussed. As an important artificial microenvironment in the space base, the environmental control and life support system (ECLSS) provides necessary resources for human. Sintering and additive manufacturing technologies demonstrate the potential to construct a space base with lunar regolith or simulants. The extraction and in situ utilization of resources on the Moon, including water ice, oxygen, and helium-3, are crucial to maintain life support for lunar exploration. Typical energy systems that can be used on the Moon include photovoltaic cell, Stirling power generation technology, closed Brayton cycle (CBC) system, Rankine cycle system, heat storage system, and integrated energy system. The CBC system has the highest thermal efficiency (39%) among them, making it suitable for late-period energy supply. The performance of various planetary rovers, the most important transportation platforms, are summarized. Through geological explorations, the resource distribution, content, and occurrence can be obtained. Perspectives on the future, promotions of environment adaptation, resource recovery, energy efficiency, and intelligence of the existing technologies are still needed to move forward on space explorations.</p>

Four-Dimensional ACC Analysis

The article discusses the issues of planning and resource management in the process of testing software systems. The paper presents the ACC analysis method used at Google to optimize the distribution of efforts for testing different parts of the system. Extending the method by adding a fourth characteristic - actors (roles of system users) – allows for a more flexible assessment of action requirements and user skill levels. Illustrative examples of system attributes and components help understand the principles of the method. The work proposes a new approach to risk management and process improvement in testing software systems in a multidimensional space. The effectiveness of applying the enhanced ACC analysis method using a risk-oriented approach was demonstrated using the example of a control system for technological operations in the repair of electric motors, for which attributes, components, actors were identified, opportunities at their intersection were analyzed, and testing was conducted, which helped improve the system's quality.

Digital Transformation: the experience of Canada, Singapore and South Korea

The timely and effective implementation of state programs in the field of digitization leads to technological and economic growth. The development of digitization demonstrates a shared vision on how to utilize information technology to support the socio-economic development of society, with a particular focus on the welfare of specific groups. In the context of the active formation of the global digital environment, the volume of digital technologies providing information, services, and infrastructure is increasing. Currently, many countries do not seek to emulate or fully adopt the data policies and practices of other nations. Each country aims to be a leader in this field and to possess a unique and distinctive system in the digital space. Canada, Singapore, and South Korea have developed their own national approaches to data management in the digital world. For instance, Canada's experience includes the adoption of cloud technologies, artificial intelligence, 5G technologies, and the creation of a positive ecological image for organizations. Singapore, in turn, has sought not only to regulate some areas of public life through "smart" solutions but also to integrate the potential of the state, private sector, and business to improve quality of life, institutional performance, and service delivery. South Korea has placed special emphasis on providing government services that address not only the social sector but also the daily needs, education, leisure, and other requirements of its citizens. This article examines the experiences of South Korea, Singapore, and Canada in addressing issues of digitization.

Non-linear oscillation of a mass attached to a stretched elastic wire in a fractal space

The challenge for a non-linear vibration system in a fractal space is more fractal dimensions than frequency-amplitude relationship, the system energy consumption depends upon its fractal property, so its best-case scenario is to establish a relationship among the fractal dimensions, frequency and amplitude. For this purpose, this paper studies a fractal-fractional vibration system of a mass attached to a stretched elastic wire in a fractal space, and its asymptotic periodic property is elucidated, the effect of the fractal dimensions on the vibration system is discussed. This paper offers a new road to fast and reliable analysis of fractal oscillators with high accuracy.

Архитектурно-градостроительная организация системы общественных пространств Ворошиловского района Волгограда «Царицынские кварталы»

The article touches on the topic of architectural and urban planning organization of the system of public spaces in the Voroshilovsky district of Volgograd under the name “Tsaritsyn Quarters”. The work emphasizes the importance of preserving and recreating the historical appearance of the Voroshilovsky district, which serves as evidence of the development and transformation of the city from Tsaritsyn to Stalingrad, and then to Volgograd. The authors of the article focus on the need to ensure the adaptation of the historical area to modern conditions and requirements, which includes the development of infrastructure, accessibility and functionality of public spaces. In particular, a concept is proposed that involves restoring historical buildings, optimizing transport infrastructure, providing access to the Volga River and creating tourist routes. The concept includes the use and reconstruction of authentic buildings and spaces of Tsaritsyn to create new public spaces, such as the Academic, Museum and Fair quarters. The proposal for the creation of “Tsaritsyn Quarters” in the Voroshilovsky district of Volgograd was developed on the basis of architectural and urban planning surveys, historical and sociological research and analysis of the existing transport and pedestrian infrastructure. The authors argue that the implementation of the developed proposals will transform the currently depressed area into a new attractive and sought-after public space of the city, thereby ensuring a balance between the preservation of historical heritage and the development of a modern urban environment.

Искусственный интеллект как часть общественной жизни: этико-правовые проблемы и пути их решения

The ethical and legal problems of artificial intelligence’s comprehensive integration into the public environment, its impact on the human life sphere are investigated. The intensity of the ongoing changes requires not only full-fledged legal regulation, but also a comprehensive study of both the positive aspects of innovations, as well as the foresight of possible threats and the formation of adequate protective mechanisms from the law point of view, from the standpoint of human moral values. It is a systematic approach and the possible negative consequences’ prevention of the artificial intelligence use that should shape the goal-setting of the development and implementation of such systems. Using scientific cognition methods, such as analysis, synthesis, system-analytical, formal-logical, system-legal, various approaches to understanding the definition of “artificial intelligence” have been studied, taking into account all the features of such systems, the necessary ways to solve the identified gaps in legal regulation related to determining the place of objects and artificial intelligence systems in the legal space. The social and practical significance of the development of robotics is touched upon, while attention is focused on the regulation of possible risks. It is concluded that it is the compliance of the functions performed by artificial intelligence with the ethical and moral canons of society that should be decisive in solving issues of responsibility. Separately, proposals are presented to determine civil liability both in cases of direct harm by robots with artificial intelligence, and in cases of damage or destruction of an artificial intelligence system by a third party to their owner.

Ecological Comfort of Green Spaces for Urban Parking

The article presents an overview of numerical solutions of computational fluid dynamics in the field of urban planning. The study is devoted to new solutions to maintain a comfortable microclimate in urban spaces in hot climates. Such territories require comprehensive urban planning and scientifically based environmental assessment. Numerical modelling in the Ansys Fluent software package is considered using the example of the influence of turbulence models on airflow parameters near a building site with and without green spaces. The article analyses the temperature and aeration conditions of the adjacent car park in three options: open (without landscaping); fenced with bushes; fenced with bushes with a canopy made of lightweight construction, without internal partitions, on the territory of an existing residential development, consisting of a group of 16-storey buildings in the new modern multi-storey micro district Karasuv in Samarkand (Republic of Uzbekistan). The performed CFD analysis provided an opportunity to determine the most effective localization of green spaces due to the consideration of their different combinations. The use of the CFD method when solving a problem makes it possible to optimize the period of pre-design analysis. The resulting numerical model of a house parking lot can be used to assess the impact of wind conditions and temperature regulation using a system of green spaces that provide stable and balanced heat input to the environment.

High energy explosive with low sensitivity: a new energetic cocrystal based on CL-20 and BMDNP

A new energetic cocrystal based on CL-20 and BMDNP.

Data-Driven Modeling of Microgrid Transient Dynamics Through Modularized Sparse Identification

Modularized sparse identification (M-SINDy) is developed in this paper for effective data-driven modeling of the nonlinear transient dynamics of microgrid systems. The high penetration of power-electronic interfaces makes microgrids highly susceptible to disturbances, causing severe transients, especially in the islanded mode. The M-SINDy method realizes distributed discovery of nonlinear dynamics by partitioning a higher-order microgrid system into multiple subsystems and introducing pseudo-states to represent the impact of neighboring subsystems. This specific property of the proposed algorithm is found to be very useful while working with re-configurable and scalable microgrids. The governing equations of the subsystems are identified through regression by mapping the nonlinear system's data to a linear system in a large functional space. The effectiveness of the M-SINDy method is tested and validated through numerical examples and comparisons with other existing identification models on a typical islanded microgrid. The method can simultaneously compute the governing equations of different subsystems and is examined to be robust to measurement noises and partial observations. This paper highlights the advances of data science in providing a potent tool for modeling and analyzing higher-order nonlinear microgrid systems. Dynamic discovery of system transients from measurements can be beneficial for designing control strategies that improve the overall microgrid stability and reliability.

Thermal segment microwell plate control for automated liquid handling setups.

Automated high-throughput liquid handling operations in biolabs necessitate miniaturised and automatised equipment for effective space utilisation and system integration. This paper presents a thermal segment microwell plate control unit designed for enhanced microwell-based experimentation in liquid handling setups. The development of this device stems from the need to move towards geometry standardization and system integration of automated lab equipment. It incorporates features based on Smart Sensor and Sensor 4.0 concepts. An enzymatic activity assay is implemented with the developed device on a liquid handling station, allowing fast characterisation via a high-throughput approach. The device outperforms other comparable devices in certain metrics based on automated liquid handling requirements and addresses the needs of future biolabs in automation, especially in high-throughput screening.

Western North American Cruise Shipping Network: Space Structure and System

Regionalization is the basic feature of cruise shipping network organization. We insist that the cruise networks of Alaska, Hawaii, etc., have developed into a whole with the scaling up of cruise tourism. To prove it, we used complex network analysis methods to explore the port connections and the spatial structure of the cruise shipping network in these regions. We found that Alaska, Hawaii, and the west coast of Mexico all belong to seasonal cruise market areas. Cruise itineraries in these areas are categorized into one‐way and round‐trip itineraries, and more than 70% of the itineraries are short duration and medium duration. These areas build cruise shipping networks used in Vancouver, Los Angeles, Anchorage, San Francisco, Honolulu, and other cruise ports, which can be subdivided into nine single‐core cruise shipping network systems and two dual‐core cruise shipping network systems. The interconnection of different systems forms a T‐shaped cruise shipping network in geographical space.

Research on design evaluation of wooden outdoor seating system

[Objective] Although there are many kinds of materials for outdoor seating, there are also limitations. People prefer natural wood materials which are warm in winter and cool in summer. From the perspective of sustainable development, wood substitute for natural preservative wood is replaceable, so it has become the main material for outdoor seating. The purpose of this paper is to verify the advantages of wood and wood -like materials in the application of outdoor seating with expert evaluation methods. [Methods] The Del phi expert evaluation method was used to optimize the different schemes of wood and non -wood materials in the empirical study. Based on the three levels of “environment - space - people ”, the evaluation was carried out from multiple perspectives, from the urban ecological environment appeals of the top system of the macro root layer to the extension system of the meso-generative layer of the harmonious space and place system, as well as the micro-representational layer ontology system problems involving the form, function and material technology of outdoor seating. [Result] Finally, based on the quantitative data analysis of Delphi expert evaluation method and standard deviation comparison analysis results, the outdoor seating system design of wood and imitation wood materials was obtained by experts’ preference and affirmation. [Conclusion] T he material selection of outdoor seating can be mainly wood, and the acceptance of imitation wood outdoor seating is similar to wood. When selecting outdoor seating materials, we can gradually introduce composite anticorrosive wood materials to replace non -renewable natural anticorrosive wood.

Factors affecting consciously improving vocabulary with a spaced repetition system

Factors affecting consciously improving vocabulary with a spaced repetition system

A Low‐Complexity Expectation Propagation Detector for OTFS

In this paper, we propose a low‐complexity expectation propagation (EP) detector for orthogonal time frequency space (OTFS) system with practical rectangular waveforms. In the high‐mobility scenario, OTFS is becoming a potential scheme for the sixth‐generation (6G) wireless communication system. However, the large size of the effective delay‐Doppler (DD) domain channel matrix brings unbearable computational complexity to the signal detection algorithm based on the matrix inversion. We propose a low‐complexity EP detector based on the sparsity and the block circulant structure of the effective channel covariance matrix in the DD domain. The proposed algorithm only requires log‐linear complexity. In addition, simulation results show that the proposed algorithm not only has the advantage of low complexity but also has good performance, which achieves a tradeoff between performance and complexity.

Enhanced spatial modulation based orthogonal time frequency space system

Enhanced spatial modulation based orthogonal time frequency space system

Sustainable reutilization of ion-adsorbed rare earth tailings: Preparation of low-cost functionalized pigments

In order to alleviate the ecological pressure caused by rare earth tailings, this study focuses on the application of ion-adsorbed rare earth tailings in the preparation of functional pigments. By using mechanical grinding and high-temperature calcination, 33 new functionalized red pigments were successfully prepared by doping iron and lanthanum elements. X-ray diffraction (XRD), scanning electron microscopy (SEM), CIE 1976 color space system, and ultraviolet–visible–near-infrared spectrophotometer were used for characterization. The synthesized pigment exhibits a rich color range from light yellow to reddish brown. Compared with commercially available iron red pigments, it exhibits significantly enhanced near-infrared reflectance, excellent acid and alkali resistance, and strong thermal stability up to 900 °C. It is worth noting that pigment P-1-2-1 achieved the best red value (L* = 43.73, a* = +24.07, b* = +15.65) with a maximum near-infrared reflectance of 91 %. Therefore, the utilization of rare earth tailings as raw materials for the preparation of functional pigments has significant effects. This study provides valuable insights for the development of eco-friendly pigments, which not only helps alleviate the urban heat island effect but also promotes the sustainable utilization of rare earth tailing resources, contributing to the achievement of carbon neutrality goals.

The uniformly continuous theorem of fractal interpolation surface function and its proof

<abstract> <p>In order to research uniform continuity of fractal interpolation surface function on a closed rectangular area, the accumulation principle was applied to prove uniform continuity of fractal interpolation surface function on a closed rectangular area. First, fractal interpolation surface function was constructed by affine mapping. Second, the continuous concept of fractal interpolation surface function at a planar point in a three-dimensional cartesian coordinate space system and uniform continuity of fractal interpolation surface function on a closed rectangular area were defined in the paper. Finally, the uniformly continuous theorem of fractal interpolation surface function was proven through accumulation principle in the paper. The conclusion showed that fractal interpolation surface was uniformly continuous function on a closed rectangular area.</p> </abstract>