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Aims at the structuring of an analytical tool that traces the time course of geophysical phenomena, regional or global, and compares it to that of long‐term solar conditions – long term meaning decades or centuries. The model is based on the postulate that since in a previous analysis the preponderance of atmospheric, hydrospheric, and some aspects of geospheric phenomena are powered by energy from the sun, now or in the past, the long‐term behaviour of such phenomena is ultimately “connected” to long‐term changes occurring in the sun itself. Proposes and models a stable surrogate pattern for the long‐term solar activity; introduces a transfer‐function for modelling the connection between the surrogate and terrestrial phenomena viewed as partners in the connection; and probes the connection outcome for episodic or unanticipated effects that may arise due to the fact that in the present context, the connection, should it exist, is very likely non‐linear. Presents the theory of the concept, and demonstrates its pertinence to terrestrial phenomena.

The presented paper aims to consider algorithm for optimal design of multilayer thermal insulation.

Developed algorithm is based on a sequential quadratic programming method.

2D mathematical model of heat transfer in thermal protection was considered in frame of thermal design of spacecraft. The sensitivity functions were used to estimate the Jacobean of the object functions.

Design of distributed parameter systems and shape optimization may be thought of as geometrical inverse problems, in which the positions of free boundaries are determined along with the spatial variables. In such problems, the missing data (i.e. the position of boundaries) are compensated for by the presence of the so-called inverse problem additional conditions. In the case under consideration, such conditions are constrains on the temperature values at the discrete points of the system.

Results are presented how to apply the algorithm suggested for solving a practical problem – thickness sampling for a thermal protection system of advanced solar probe.

The procedure proposed in the paper to solve a design problem is based on the method of quadratic approximation of the initial problem statement as a Lagrange formulation. This has allowed to construct a rather universal algorithm applicable without modification for solving a wide range of thermal design problems.

The purpose of this paper is to investigate the dark properties as a function of reverse current induced defects. Dark characteristics of solar modules are very essential in the understanding the functioning of these devices.

Reverse currents were applied on the photovoltaic (PV) modules to create defects. At several time intervals, dark characteristics along with surface temperature were measured.

Current-voltage (I-V) and capacitance-voltage (C-V) characteristics furnished valuable data and threshold values for reverse currents. Maximum module surface temperatures were directly related to each of the induced reverse currents and to the amount of leakage current. Microstructural damages, in the form of hot spots and overheating, are linked to reverse current effects. Experimental evidence showed that different levels of reverse currents are a major degrading factor of the performance of solar cells and modules.

These results give a reliable method to predict most of the essential characteristics of a silicon solar cell or a module. Similar test could help predict the amount of degradation or even the failure of PV modules.

The purpose of this paper is to implement coating system by varying the amount of nano-sized titanium dioxide, (nano-TiO₂) combined with various organic binders and to study the coating effects on the performance of solar cell in terms of temperature and efficiency.

Nano-TiO₂ coatings are developed in two types of binder networks; the combination of methyltrimethoxy silane (MTMS) and nitric acid and the combination of 3-aminopropyl triethoxysilane (APTES) and MTMS. Overall, the formulations method was cost-effective, produces good transparency, clear and managed to dry at room temperature. The coating mixtures were applied onto the glass substrate by using the dip-coating method and the coated substrate were sent for several characterizations.

This study demonstrated that TiO₂ nanoparticle coating in APTES/MTMS matrix showed a thermal-decreasing result on solar cells, where the cell temperature is reduced to 46.81°C (T₂ coating type) from 55.74°C (without coating) after 1-h exposure under 1,000 W/m² irradiance in a solar simulator. Contrary to prior works where solar cell coatings were reported to reduce the cell temperature at the expense of the cell efficiency, the results from this study reported an improved fill factor (FF) of solar cells. From the photovoltaic (PV) characteristics study, the FF for solar cells is increased by approximately 0.2, i.e. 33.3 per cent, for all coatings compared to the non-coated cell.

Findings will be able to contribute in the development of temperature-reducing and efficiency-enhancing coating for PV panels.

A simple dip-coating method provides an even distribution of TiO₂ nanoparticle coating on the glass panel, which is cost-effective and time-efficient to reduce the temperature of solar cell while maintaining its efficiency.

The ability of nano-TiO₂ coatings with a simple fabrication method and the right solution to reduce the surface temperature of solar cells while improving the FF of the cells.

The purpose of the paper is to give a brief description of the new topic introduced for the first time at the EASN Conferences.

The topic concerns the heliosphere, the nearest surrounding of the Sun and thus the nearest vicinity of the Earth. The heliosphere is created due to the interaction between the solar wind and the local interstellar medium.

This paper does not include any new information about the heliosphere and only introduces a new topic to this journal. It is briefly shown how heliospheric structures are formed, what factors affect a shape of the heliosphere, what measurements are made by Ulysses, Voyager and IBEX space missions (important for the heliosphere modeling) and how obtained data are used to validate theoretical results.

To categorize the paper under one of these classifications, research paper, viewpoint, technical paper, conceptual paper, case study, literature review or general review, the authors chose a paper type, general review, as the closest category to this paper. However, it is not a purpose of this paper to provide an extensive review of the community efforts to investigate the physical processes in the vicinity of the heliosphere interface. This is mostly a status report.

As the new topic in this journal, the article introduces in detail only a small number of aspects connected with heliosphere models. Interplanetary and interstellar magnetic field structures are primarily described. Other factors are only mentioned.

Author's preference for use of term magnetofluidmechanics instead of magnctohydromechanics; résumé of main principles; applications of the science in astronautics.

The purpose of this paper is to provide a review of past experience in managing risk and technical innovation in NASA space programs with lessons learned for new unmanned space missions.

The paper examines past performance of space missions and abstracts the lessons learned for the efficient development of cost‐effective space missions.

The paper finds that large organizations build and internalize a culture at odds with risk taking and the rapid deployment of innovative solutions. Actualized management goals are often at odds with the issues that determine or insure the long‐term survival of an organization. A key issue is the management of knowledge within that system: the extrinsic knowledge of the technologies as well as the intrinsic knowledge associated with the perception and acceptance of risk.

Innovation can be seen as being dangerous to the organization. That perception must be managed. The NASA culture that is applicable to human spaceflight may not serve the community or the organization as well when applied to unmanned missions.

The paper provides a simplified and brief perspective on the issues inherent in managing a change in culture in an organization that has a highly public mission.

While the NASA “faster, better, cheaper” program has been considered elsewhere, this paper focuses on the lessons that are applicable to the management of space missions and the development of new, cost‐effective programs. These lessons retain their value, as the new administrator Michael D. Griffin attempts to manage the transition of NASA from an organization that has been in maintenance mode to one that must embrace innovation and stay within a highly constrained funding profile.

THE German aerospace industry faces the new decade with optimism. Even the budget restrictions announced recently which affect most parts of the industry cannot lessen that impression. Some of the money not granted has only been frozen to avoid further overheating of the economy. In comparison with the aerospace industries of Great Britain — employing 240,000 people — and France — employing 100,000 people — the German aerospace industry with its 52,000 employees seems to be of less importance. This figure, however, is remarkable with regard to the fact that in 1956 this industry had to start from nothing. The airframe industry employs about 32,500, the space industry some 2,600, the engine industry about 6,200, the material and accessory industry 3,000 employees, and in the equipment industry another 7,200 people are working directly for the aerospace industry.

DURING the past year (the Advisory Council stated) we were asked to consider the question of British participation in space research and, in particular, a proposal originating with a group of Fellows of the Royal Society led by Professor H. S. W. Massey, that the United Kingdom should embark upon a programme of scientific experiments in the upper atmosphere and in extraterrestrial space, by means of a series of earth satellites launched by vehicles developed from British military rockets adapted to this purpose.