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The use of main battle tanks in armies goes back many years. The most crucial component is undoubtedly the weapon system. In this study, it is aimed to model the elevation dynamics of the weapon system that provides the movement of the weapon system in the vertical axis. The elevation dynamics consists of three parts: an electric motor, a driver, and a barrel. Both parts are expected to have similar vibration characteristics. The linear graph method was preferred as the modeling method. First of all, the system components and types were determined, and the linear graph, normal tree, and tree links of the system were drawn. Then the state variables, primary and secondary variables, as well as the number of branches, nodes, and sources, were determined, respectively. Elemental, continuity, and compatibility equations were written using the obtained graphs. By organizing these equations, state equations were obtained in standard form and matrix form. With the simulation studies carried out in MATLAB/Simulink, the displacement, velocity, and acceleration responses of the breech and muzzle sections were obtained. It is seen that obtained angular displacement, velocity, and acceleration results for both breech and muzzle sections are almost the same. As a result, the breech and muzzle sections have similar vibration motions and have proven to be able to work in harmony. This result shows that the barrel can be designed from two parts without additional stress and tension, which makes it difficult to focus on the target. By forming the barrel in two parts, the risk of damage can be minimized by better distributing the stress and tension occurring in the barrel during firing. [ABSTRACT FROM AUTHOR]

Abstract Climate change threatens to push species to higher elevations and eventual extinction. Birds, in particular, are shown to be shifting upslope in the Neotropics and Southeast Asia. Yet previous studies have lacked the temporal resolution to investigate distributional dynamics over time in relation to climatic fluctuations, especially in the understudied Afrotropics. Here, we used 15 years of point‐count data from across an elevational gradient (1,767–2,940 m) in Rwanda, to assess elevational shift rates and dynamics in a community of Afrotropical birds. In general, species shifted their elevations upslope by 1.9 m/year, especially at their lower elevational limits which shifted by 4.4 m/year. Importantly, these shifts occurred despite the fact that local temperature and precipitation showed little trend over the study period. Moreover, the interannual distributions of few species were associated with temperature, suggesting that temperature played little direct role in determining elevational distributions of birds. Instead, upslope shifts may be more related to incremental shifts in habitat and resources which lag behind decades of increased temperature in the region. Precipitation appeared to have more of an effect than temperature in determining interannual elevational changes, allowing species to expand their ranges in years of higher rainfall. Our results highlight the need to understand the mechanisms driving upslope shifts as they occur throughout the tropics. It will be critical for montane regions of the tropics to preserve contiguous blocks of forest across elevational gradients to allow wildlife to shift unimpeded.

Climate change threatens to push species to higher elevations and eventual extinction. Birds, in particular, are shown to be shifting upslope in the Neotropics and Southeast Asia. Yet previous studies have lacked the temporal resolution to investigate distributional dynamics over time in relation to climatic fluctuations, especially in the understudied Afrotropics. Here, we used 15 years of point‐count data from across an elevational gradient (1,767–2,940 m) in Rwanda, to assess elevational shift rates and dynamics in a community of Afrotropical birds. In general, species shifted their elevations upslope by 1.9 m/year, especially at their lower elevational limits which shifted by 4.4 m/year. Importantly, these shifts occurred despite the fact that local temperature and precipitation showed little trend over the study period. Moreover, the interannual distributions of few species were associated with temperature, suggesting that temperature played little direct role in determining elevational distributions of birds. Instead, upslope shifts may be more related to incremental shifts in habitat and resources which lag behind decades of increased temperature in the region. Precipitation appeared to have more of an effect than temperature in determining interannual elevational changes, allowing species to expand their ranges in years of higher rainfall. Our results highlight the need to understand the mechanisms driving upslope shifts as they occur throughout the tropics. It will be critical for montane regions of the tropics to preserve contiguous blocks of forest across elevational gradients to allow wildlife to shift unimpeded. Across 15 years of bird count data in Nyungwe National Park, Rwanda, we show that species have shifted their elevations upslope. However, these shifts did not coincide with increases in temperature. There was little association between temperature fluctuations and bird distributions but birds appeared to expand their distributions in wetter years. [ABSTRACT FROM AUTHOR]