Papers by Keyword: Space

Abstract: Cumulative heavy-ion irradiation effects were investigated in a commercial 4H-SiC double trench MOSFET through a combination of cyclotron experiments and TCAD simulations. Devices were exposed to continuous ¹²⁴Xe³⁵⁺ ion strikes at a linear energy transfer (LET) of 63 MeV·cm²/mg under drain biases from 100 to 400 V. Experimental results revealed the onset of permanent drain and gate leakage at voltages as low as 200 V, with degradation rates increasing by several orders of magnitude at higher bias. Post-irradiation measurements confirmed trench oxide rupture and source leakage path formation, establishing single-event leakage current (SELC) as the dominant degradation mechanism. In contrast, TCAD simulations of isolated ion strikes predicted catastrophic single-event burnout (SEB) only at or above 250–300 V, highlighting the critical role of cumulative damage processes that are not captured in single-strike models. These findings demonstrate that permanent leakage-driven degradation effectively extends the SELC zone beyond conventional SEB thresholds, reducing the safe operating area of trench-based SiC MOSFETs. The results have significant implications for derating strategies in space applications, where current SEB-focused guidelines may underestimate vulnerability, and highlight the need for radiation-hardening by device design to ensure long-term reliability.

Abstract: This work proposes SiC half-bridge modules to improve the high-power motor drive systems in space. The high current capability of the modules allows to reduce the number of required components, reducing the required PCB area. Using analytical loss calculation models the losses and the efficiency of the Si and SiC configurations is calculated, obtaining better results with the SiC due to the lower conduction losses, even if the voltage rating of the devices is severely derated to avoid single event burnouts in the space application.

Abstract: Space environment is rich of high energy particles that form the radiation field. Human beings as well as electronic devices are susceptible to their action, even if the exposure time is limited. For this reason, radiation shields are needed to carry out safe space missions. Traditionally, in-space shielding frames are made up of aluminum, but more recent studies have shown that a good shielding efficiency can be achieved by hydrogen (H)-rich materials, as polyethylene (PE). Moreover, it was noticed that small mass atoms as H, boron (B) and nitrogen (N) can reduce secondary emissions. In this work, radiation shields of high-density PE (HDPE) filled with boron nitride (BN) have been manufactured. Since BN particles dispersion into the polymeric matrix strongly affects the composite shielding ability, 2 filling routes have been investigated. The first manufacturing strategy is about melt-mixing: HDPE is melted at 200 °C into a batch-mixer, then BN powder is inserted, and mixing is carried out until the torque exerted by the rollers reaches a plateau. Subsequently, the shield is obtained by molding and machining. The second strategy is about the filler spray deposition; BN is spayed on HDPE plates surface after which stacking occurred and consolidation is carried out at 130 °C for 24 h. At the end, machining is performed. The shields dimensions are 25x25x10 mm³ and 50x46x35 mm³, respectively. Both of them show a good level of agglomeration and a good fillers dispersion, with a final density close to the HDPE nominal value.

Abstract: The aim of the paper is to explore and establish a base for a possible development of a more holistic and spatially-inclusive method for evaluating energy performance of buildings. This is to be achieved by envisioning building envelopes as arrangements of spatial zones, which could improve the overall energy balance of buildings but at the same time reduce the usage of construction materials and thus consumption of production energy and built-up space. The wall deconstructed in spatial zones, as shown e.g. in Antivilla by Brandlhuber-+, opens a series of questions about the future of existing building codes and certification tools. The potentials are discussed based on the aspects of flexibility, responsiveness, adaptability, replaceability and affordability. The analysis outlines the benefits of the inclusion of those paradigms in the definition of sustainable architecture, and at the same time exposes the lack of possibility to reflect their potential by the established certification criteria. The paper aims at opening the discussion about the limits and traps of quantifying architecture and calls for rethinking of established schemes of sustainability in building sector.

Abstract: One of the prior directions in the high-rise buildings formation was the use of spatial voids in their architectural solution. This article discusses the world experience in the design and construction of high-rise buildings, the formation of which is based on techniques connected with the use of spatial voids. On the design experience analysis basis is revealed through the classification of unique high-rise buildings architecture formation existing methods on the basis of application of spatial voids in their figurative decisions. The five main shape-forming schemes of high-rise buildings based on the use of spatial voids in their structure: gallery, bridge, arch, closed, combined (hybrid) are defined. The basic principles of high-rise buildings architecture formation with application of spatial apertures in their volume solutions are determined. The work's practical significance in the possible application of the obtained study results, both in project practice and for the further theoretical research is specified.

Abstract: Today, the small and medium-sized production facilities form a regular part of countryside. Many of them, however, lost their original function: they are abandoned, unattended, they dilapidate. As such, they have become a problem issue for villages and the country in general. No matter how slow and complicated there are solutions to this dire situation, nevertheless.

Abstract: In this paper the authors present some considerations regarding the necessity and the methods to calibrate an exoskeleton elbow module. Prior researches and studies are indicating that there is a difference between the haptic device force reaction and situation (position and orientation) and similar parameters at the level of the guided or slave robot. The authors are investigating the causes of the pose accuracy and force errors knowing the fact that for some space operations the fidelity of the teleoperation the geometric, kinematic and dynamic parameters are of great importance. The authors propose the measurement of the position accuracy, position repeatability, static relaxation under load, speed and acceleration, force and torque measurement in order to obtain a real correlation between the haptic device and the space robot parameters. Also the authors are considering the investigation of the unwanted vibration and the effect on the teleoperation parameters. Considering the importance of calibration for the improvement of the general accuracy of teleoperation the authors are taking into account the development of several performance indicators as a consequence of the conclusions emerged from the calibration methods study above mentioned. Also they consider very important that the calibration methods must be specific for each application category and therefore moderated performance indicators are envisaged.This template explains and demonstrates how to prepare your camera-ready paper for Trans Tech Publications. The best is to read these instructions and follow the outline of this text.

Abstract: The accuracy of outer space robotic applications using haptic devices requires high performance of the haptic device connected with the remote robot. The paper introduces and develops a quality indicator system, able to give overall information on the performances of the haptic device. The authors define several categories of indicators, such as the geometric, kinematic and dynamic. The geometric category comprises the position and orientation accuracy, the repeatability, the trajectory fluctuation, the resolution, the working space and the static relaxation. The kinematic indicators category comprises the speed fluctuation, the maximal acceleration and time accuracy. The dynamic indicators category comprises the force and torque fluctuation, the vibration amplitude and acceleration. All above-mentioned simple indicators open the path to complex indicators such as the pose accuracy in relation with the working space or the maximum force/torque in respect with the total weight. By introducing moderated indicators, the authors consider the specificity of each group of tasks or applications and in the end, they introduce a global moderated indicator in order to quantify rapidly the general performance level of a certain haptic device.

Abstract: As the extension module of ArcView GIS, ArcView 3D Analyst can visually provide three-dimensional surface model and interactive three-dimensional perspective observation function. Its principle is to use ArcView software to handle AutoCAD elemental topographic map data, and then set up digital elevation model (DEM) through geographic information system. The essay takes the project of turning Huaiyin Village, which is located at Guyang Town, Zhenjiang city, into a new style village through space transformation as an example to present how to use spatial three-dimensional data analysis to settle down land distribution and statistics problems during the transformation and give effective planning proposals to the village construction.

Abstract: LOFT is the use of old industrial warehouses and old factories open, spacious, full of personality to build, contagious new cultural and creative industries to gather. Art LOFT This perfect blend of modern and post-industrialization, and has evolved into a fashionable residential lifestyle, showing her unique charm, allows designers to develop freely in this space.