Planetary science at the NASRDA-Center for Basic Space Science

<p>Planetary science research was instituted at CBSS in 2016 with the mandate to study the planetary activities within our Solar System. Therefore, the research activities of group were categorized into two: Environmental and Life sciences. The environmental science team studies the physical evolution of the other planets in our solar system using data from various missions like MAVEN (Mars Atmospheric and Volatile EvolutioN), while the life science team are looking at the probability of finding life elsewhere in our solar system. So far some of researches had been published by these teams, while more are various levels of development. Some of the researches are on evolutionary panspermia and meteorite sample analysis.</p> <p>Our research activities have been enhanced through collaborations such as the PAPSSN project, analysis of meteorite samples at University of Witwatersrand in South Africa etc.</p>

Neoclassical Realism in Japan’s Space Security

Japan’s space security commands attention as the country shifts toward internationalism in a world returned to great power competition. Using the framing from neoclassical realism, this article discusses the ways in which Japan has adjusted both its internal portfolio and its external postures to balance against perceived threats in outer space. While neoclassical realism is foundational for understanding what motivates, empowers, and constrains states in the space domain, the article also layers in the importance of international law to the conduct of statecraft within it. Doing so gives us a more holistic understanding of the material, legal, and normative evolution of Japan’s winding space trajectories. Although Japan’s Basic Space Law of 2008 is seen as a watershed event for legal and policy purposes, the law merely caught up with the extraordinary quality and range of Japan’s long-evolving dual-use space technologies. It is these autonomous foundations that empower Japan to pursue three distinct strategies in its interest—counterspace capabilities, organizational changes, and space diplomacy—with implications for both rivals and allies in a changed world order.

Research Status and Prospects of Tribological Behaviors of Key Friction Pairs of Materials in Marine Equipment

Marine environment provides a basic space for human survival and social sustainable development. The study of tribological problems and mechanism of marine engineering materials in the sea extreme environment has become one of key technologies to be developed urgently in the field of marine engineering. This review summarizes and analyzes the tribological research of key friction materials in marine environment, focuses on tribological properties of ceramic, polymer and metal, emphatically introduces the current situation and development trend of tribological research in marine environment, such as metal and metal pairs, ceramics and metal pairs, polymers and metal pairs, polymers and ceramic pairs, and aims to provide a tutorial reference for the selection and application of friction pairs of marine engineering equipment.

Protection Value of Tropospheric Radio Refractivity over Nigerian Atmosphere

This study enumerates the protection values derivable from refractivity variation of the tropospheric surface in Nigeria. The investigation was conducted in four cities of Nigeria using meteorological data of 2008 procured from the centre for basic space science (cbss), university of Nigeria, (unn), Nsukka. Data were captured from four different stations: Akure, Nsukka, Minna and Sokoto using vantage pro II automatic weather station. Data measurement at half hourly interval for the whole year took place at the ground level, 0 m and 100 m altitude of the troposphere. The results of the analyzed data revealed that at 100 m altitude, Nzukka and Akure experienced better protection at refractivity value of 350 unit than Sokoto and Minna at 250 unit. At the ground level (0) m, refractivity values becomes more distinct with; Nzukka, 500 unit, Akure, 370 unit while Minna and Sokoto shared the same refractivity value of 270 unit. This trend of refractivity variation showed a decreasing order of protection against exposure to damaging effects of the cosmic and out of space radiation as we move from the south towards the northern part of the country.

Centered planes in the projective connection space

The space of centered planes is considered in the Cartan projec­ti­ve connection space . The space is important because it has con­nec­tion with the Grassmann manifold, which plays an important role in geometry and topology, since it is the basic space of a universal vector bundle. The space is an n-dimensional differentiable manifold with each point of which an n-dimensional projective space containing this point is associated. Thus, the manifold is the base, and the space is the n-dimensional fiber “glued” to the points of the base. A projective space is a quotient space of a linear space with respect to the equivalence (collinearity) of non-zero vectors, that is . The projective space is a manifold of di­men­sion n. In this paper we use the Laptev — Lumiste invariant analytical meth­od of differential geometric studies of the space of centered planes and introduce a fundamental-group connection in the associated bundle . The bundle contains four quotient bundles. It is show that the connection object is a quasi-tensor containing four subquasi-tensors that define connections in the corresponding quotient bundles.

Reidemeister classes for coincidences between sections of a fiber bundle

Let $s_0,f_0$ be two sections of a fiber bundle $q: E\to B$ and the coincidence set $\Gamma(s_0,f_0)\neq \emptyset$. We consider the following question: Is there $s_0\simeq_B s_1$ (by the homotopies which cover the constant homotopy $\overline{I}_B$ on the basic space) such that $\Gamma(s_1, f_0)=\emptyset$? If $b_0\in \Gamma(s_0,f_0)$ and $F_0=q^{-1}(b_0)$ is the typical fiber, in this context we can use the homotopy lifting extension propriety of the fibration $q$ to obtain homotopies over $B$. When we make this and the basic point are fixed we can use the elements $s_0(\beta), f_0(\beta^{-1})$ where $\beta \in\pi_1(B,b_0)$ and the elements $\gamma\in \pi_1(F_0,e_0)$. So we will introduce the algebraic classes of Reidemeister relative to the subgroup $\pi_1(F_0,e_0)$. When the basic points are not fixed we need to consider the classes $[\til{s}]_L$ of lifting of $s_0$ defined on the universal covering $\til{B}$ to $\til{E}$. The present work relates the lifting classes $[\til{s}]_L$ of $s_0$ and the algebraic relative Reidemeister classes $R_A(s_0,f_0; \pi_1(F_0,e_0).$

Impactos dos parâmetros em Modelos de Interação Espacial: uma discussão metodológica / Impacts of parameters in Spatial Interaction Models: a methodological discussion

Interessantes aplicações dos dados espaciais são vistas em estudos de interação espacial que usam modelos matemáticos adaptados de outras ciências ou criados para contextos específicos e, em geral, os principais elementos nas expressões algébricas que representam esses modelos são: as distâncias entre as Unidades Espaciais Básicas (UEB) e a magnitude (massa) de cada UEB. O problema discutido neste trabalho é: ao usar diferentes atributos ou medidores de distância os resultados obtidos com a aplicação de modelos matemáticos de interação espacial podem provocar conclusões distintas? Neste estudo foi aplicado o Modelo Potencial para cálculo e avaliação do potencial de atração dos municípios da Mesorregião do Triângulo Mineiro/Alto Paranaíba. Os resultados deste trabalho mostram que a escolha de variáveis e a forma de medir distância provocam resultados com diferenças significativas dentro de um mesmo modelo matemático que lida com a interação espacial.Palavras–chave: Interação Espacial, Modelos, Métodos QuantitativosAbstract Interesting spatial data applications are seen in spatial interaction studies using mathematical models adapted from other sciences or created for specific contexts, and in general the main elements in the algebraic expressions representing these models are: the distances between the Basic Space Units (BSU) and the magnitude (mass) of each (BSU). The problem discussed in this work is: when using different attributes or distance metrics can the results obtained with the application of mathematical models of spatial interaction lead to different conclusions? In this study the Potential Model was applied to calculate and evaluate the attraction potential of the municipalities of the Triângulo Mineiro / Alto Paranaíba Meso-region. The results of this work shows that the choice of variables and the way of measuring distance causes results with significant differences within a same mathematical model that deals with the spatial interaction.Keywords: Spatial Interaction, Models, Quantitative Methods