Sustainable Development Concerning with Mankind’s Climate Changes

Mankind has witnessed many outstanding weather happenings which determined radical climate changes and thus, the draught is expected further to grow. Many experts, academics and scientists all over the continents have strongly called for attention about the importance of saving the water, either for housing and industrial consumers. According to the February - 2007 UNO Report, Terra is the subject of an accelerated global heating process, firstly due to the carbon emissions. Several decades further the climate changes will continue even if, theoretically, these emissions could partly be stopped. As one of the official UNO’s institutions, the World Meteorology Organisation certified the global heating and alerts about another worrying phenomenon,namely the soil disaster.environment, climate changes, global warming, greenhouse effect, sustainable development, EU policy on the environment, climate protection

Analysis of Main Social Indicators Developments Regarding Labour Market in 2007-2009 in Romania

Labor markets at international level, European and equally in Romania, registered in terms of globalization, European integration and the global financial crisis, many transformations while maintaining sustainable competitiveness, new challenges and major risks for the viability of social protection systems. Thus, must be considered: the dynamics of employment rates, occurrence or loss of paid employment, more flexible occupational system, motivational payment, development of new skills for new jobs, promote a professional and geographical mobility, all having major implications for social protection functionality, now and especially in the future. Employment and human capital management in Romania, extends far beyond the actual policies of the labor market, because the employment policy of Romania must be formed in a component of national growth and development strategy, adapted to employment policies of the European Union, globalization of economies, in the context of the current financial crisis.employment, globalization, global financial crisis, unemployment, wages, pensions, employment rate, professional skills, occupational system

Impact ejecta and crater formation on asteroid surfaces

Asteroids in the Solar System are numerous and have varied composition. Analysis of impact crater sizes and morphologies on asteroids can provide a direct diagnosis of the surface material properties and near-surface structures. This thesis describes numerical simulations of impacts into low-gravity asteroid surfaces using the iSALE shock physics code to inform this diagnosis. Asteroids may pose a future catastrophic threat to Earth and to avoid it, the incoming asteroid can be deflected by a spacecraft impact. However, the efficiency of the deflection is determined by target properties. This work considered different target scenarios to determine the sensitivity of crater morphology, ejecta mass-velocity distribution and momentum transferred, to asteroid surface properties and shallow structures. For homogeneous targets, the surface cohesion, initial porosity, and internal friction were found to greatly influence ejecta mass/velocity distributions and the amount an asteroid can be deflected. In a two-layer target scenario, the presence of a less porous, stronger lower layer can cause both amplification and reduction of ejected mass and momentum relative to the homogeneous case. Impacts into targets with decreasing porosity with depth only produced an enhancement in the ejected momentum for sharp exponential decreases in porosity. Using reasonable estimates for the material properties of the Double Asteroid Redirection Test (DART) asteroid target, the simulations show that the ejecta produced from the impact can enhance the deflection 2 to 4 times. Simulations of impacts into possible target structures on Psyche show large diversity in possible crater morphologies that the ‘Psyche’ mission could encounter. If Psyche’s interior is homogeneous, then the mission will find simple bowl-shaped craters, with a depth-diameter ratio diagnostic of rock or iron. If Psyche has a layered structure, the spacecraft could find craters with more complex morphologies, e.g. concentric or flat-floored craters. Based on 3-4 proposed large craters on Psyche’s surface, model size-frequency distributions suggest that Psyche could be at least 3 billion years old if rocky and more than 4 billion years old if metal-rich.Open Acces

Heliocentric Effects of the DART Mission on the (65803) Didymos Binary Asteroid System

The Double Asteroid Redirect Test (DART) is NASA’s first kinetic impact–based asteroid deflection mission. The DART spacecraft will act as a projectile during a hypervelocity impact on Dimorphos, the secondary asteroid in the (65803) Didymos binary system, and alter its mutual orbital period. The initial momentum transfer between the DART spacecraft and Dimorphos is enhanced by the ejecta flung off the surface of Dimorphos. This exchange is characterized within the system by the momentum enhancement parameter, β, and on a heliocentric level by its counterpart, βe. The relationship between β and the physical characteristics of Dimorphos is discussed here. A nominal set of Dimorphos physical parameters from the design reference asteroid and impact circumstances from the design reference mission are used to initialize the ejecta particles for dynamical propagation. The results of this propagation are translated into a gradual momentum transfer onto the Didymos system barycenter. A high-quality solar system propagator is then used to produce precise estimates of the post-DART encounters between Didymos and Earth by generating updated close approach maps. Results show that even for an unexpectedly high βe, a collision between the Didymos system and Earth is practically excluded in the foreseeable future. A small but significant difference is found in modeling the overall momentum transfer when individual ejecta particles escape the Didymos system, as opposed to imparting the ejecta momentum as a single impulse at impact. This difference has implications for future asteroid deflection campaigns, especially when it is necessary to steer asteroids away from gravitational keyholes

Reshaping and ejection processes on rubble-pile asteroids from impacts

Context. Most small asteroids (<50 km in diameter) are the result of the breakup of a larger parent body and are often considered to be rubble-pile objects. Similar structures are expected for the secondaries of small asteroid binaries, including Dimorphos, the smaller component of the 65 803 Didymos binary system and the target of NASA’s Double Asteroid Redirection Test (DART) and ESA’s Hera mission. The DART impact will occur on September 26, 2022, and will alter the orbital period of Dimorphos around Didymos. Aims. In this work we assume Dimorphos-like bodies with a rubble-pile structure and quantify the effects of boulder packing in its interior on the post-impact morphology, degree of shape change, and material ejection processes. Methods. We used the Bern smoothed particle hydrodynamics shock physics code to numerically model hypervelocity impacts on small, 160 m in diameter, rubble-pile asteroids with a variety of boulder distributions. Results. We find that the post-impact target morphology is most sensitive to the mass fraction of boulders comprising the target, while the asteroid deflection efficiency depends on both the mass fraction of boulders on the target and on the boulder size distribution close to the impact point. Our results may also have important implications for the structure of small asteroids

The impact of bushfires on water quality

Population growth in urban areas leads to a higher demand in water use. Quality of water is an important factor not only from an aesthetic view, but also for ecological health purposes. This paper presented research that is designed to develop a spatial approach to support the planning of the water quality in the areas subjected to bushfires, using a case study from state of Victoria. In particular, this research involved the implementation of a hydrological model in order to predict the river water quality, to assist in the decision-making process. The impact of bushfires on water quality can be highly variable for the most of the individual water quality parametres. This variability is caused by a number of landscape influences and climatic factors, most notably rainfall. High magnitude and intense rainfall events soon after fire generate the largest impacts on water quality and sometimes trigger extreme erosion events. There are many important water quality parameters that must be taken into account when the water is delivered to the population. For some of the water quality parameters there is very little information available, which makes it difficult to draw conclusions about bushfire impacts. The monitoring campaigns are very expensive, and better options are the modeling tools. The model used in this research is eWater, a conceptual, semi-distributed model, which applies the flow accumulation principles. eWater Source - Australia&#039;s National Hydrological Modelling Platform (NHMP) &amp;ndash; is developed by eWater CRC, Australia. It is designed to simulate all aspects of water resource systems to support integrated planning, operations and governance from urban, catchment to river basin scales including human and ecological influences. The catchment analyzed can be divided into sub-catchments and functional units. The model integrates rainfall runoff, constituent generation and filter models, which are parameterized. The user must find the best set of parameters that is suitable for that catchment. After calibration and validation, the model can be used in the same catchment for any period of time, and it will be able to predict the pollution levels in the catchment, with a good accuracy. Also, a user can follow the same steps, to calibrate the model for any other catchment. This method is time consuming, but it doesn&amp;rsquo;t require many input data.The fires and the rain are classified in 3 classes each. Then, the landuse, the burnt areas and the areas with rain are combined and parameterized separately. The outputs from the developed model are good correlated with the measured data, and show higher concentrations of suspended sediment and nutrients after bushfire followed by rain. To improve the model performance, the measured water quality data must be daily data with a better accuracy

Constraining surface properties of asteroid (162173) Ryugu from numerical simulations of Hayabusa2 mission impact experiment.

The Hayabusa2 mission impact experiment on asteroid Ryugu created an unexpectedly large crater. The associated regime of low-gravity, low-strength cratering remained largely unexplored so far, because these impact conditions cannot be re-created in laboratory experiments on Earth. Here we show that the target cohesion may be very low and the impact probably occurred in the transitional cratering regime, between strength and gravity. For such conditions, our numerical simulations are able to reproduce the outcome of the impact on Ryugu, including the effects of boulders originally located near the impact point. Consistent with most recent analysis of Ryugu and Bennu, cratering scaling-laws derived from our results suggest that surfaces of small asteroids must be very young. However, our results also show that the cratering efficiency can be strongly affected by the presence of a very small amount of cohesion. Consequently, the varying ages of different geological surface units on Ryugu may be due to the influence of cohesion

Spacecraft Geometry Effects on Kinetic Impactor Missions

The DART (Double Asteroid Redirection Test) mission will impact a spacecraft on the secondary (Dimorphos) of the binary asteroid system Didymos in 2022 September, with the goal of altering the orbital period of Dimorphos about Didymos sufficiently to be observed from ground-based observations. Numerical impact modeling is a crucial component in understanding the outcome of the DART experiment, and while many have investigated the effects of target properties, such as material strength and porosity (which remain unknown), an often overlooked factor is the importance of accurately representing the spacecraft itself in such models. Most impact modeling to date has considered simple impactor geometries such as a solid uniform sphere, but in reality the spacecraft is a complex shape full of different components, open spaces, and thin walled structures. At a minimum, a simple solid representation underestimates the surface area of the impact: for a small body such as Dimorphos (approximately 160 m in diameter), the difference between a spacecraft spanning 20 m (including solar arrays) impacting and a sub-1 m idealized shape may be important. In this paper, we compare models impacting high-fidelity models of the spacecraft based on the CAD geometry with various simplified impactors, in order to assess the potential importance of this effect. We find that the difference between the simplest impactor geometries (such as a uniform sphere) and the real spacecraft is measurable, and has an interesting dependence on the material properties of the asteroid itself