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Nowadays energy saving is a topical issue due to increasing fuel costs and this aspect is amplified by more stringent emissions regulations that impact on vehicle development. A recent study conducted by the U.S. Department of Energy shows that about five percent of the U.S. energy consumption is transmitted by fluid power equipment. Nevertheless, this study also shows that the efficiency of fluid power averages 21 percent. This offers a huge opportunity to improve the current state-of-the-art of fluid power machines, in particular to improve the energy consumption of current applications. These facts dictate a continuous strive toward improvements and more efficient solutions: to accomplish this objective a strong reduction of hydraulic losses and better control strategies of the hydraulic systems are needed. In fluid power, there exist many techniques to reduce/recover energy losses of the conventional layouts, e.g. load sensing, electrohydraulic flow matching, independent metering, etc. One of the most efficient ways to analyze these different layouts and identify the best hydraulic solution is done through virtual simulations instead of prototyping, since the latter involves higher investment costs to deliver the product into the market. However, to build a fluid power machine virtual model, some problems arise relative to different aspects, for instance: loads on actuators (both linear and rotational) are not constant and pumps are driven by a real engine whose speed depends on required torque. Furthermore, it is important to achieve higher level of detail to simulate each component in the circuit: the greater detail, the better the machine behavior is portrayed, but it obviously entails heavy impact on simulation time and computational resources. Therefore, there is a need to create mathematical model of components and systems with sufficient level of detail to easily acquire all those phenomena necessary to correctly evaluate machine performance and make modifications to the fluid power component design. In this context, a hydraulic proportional valve PVG 32 by Danfoss is taken as an object of study, its performance is analyzed with suitable mathematical model and simulation is done to observe closeness of a model to the laboratory experiment.

As a consequence of globalization, the world’s economies are merging; nonetheless, concerns about how globalization trends may harm the environment locally and worldwide are growing. The globalization-environment nexus has now become a contentious issue among policymakers. As a result, several empirical research studies on the globalization-environment nexus have been conducted. In the context of the environmental Kuznets curve theory, this study explores the influence of globalization on environmental deterioration in Kazakhstan (EKC). Furthermore, energy is a control variable in this research. Unit roots and structural break are used to solve the issue of non-stationarity in time series. The autoregressive distributed lagged (ARDL) model is used in this research for long run relationships between variables as well as to estimate long run and short run coefficients. Income, energy, and globalization are discovered to have a long-term link. Furthermore, the findings revealed that long-term environmental deterioration was exacerbated by economic, political, and social globalization, since these factors were shown to have a positive impact on carbon emissions in Kazakhstan. Energy is to blame for environmental damage both in the short and long term. Furthermore, this research reveals that the EKC theory exists in Kazakhstan. On the basis of the findings, policy suggestions are made.

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