The analysis of cruise ships is focusing on port areas where they may represent a significant source of anthropogenic emissions. In order to determine the correlation between cruise ship activities ...(hoteling and maneuvering) in ports with the ambient concentration of pollutants associated with marine diesel fuel combustion, the low-cost sensors are finding their market share due to lower prices compared to the referent ones. In this study, a network of four low-cost PM sensors was used to determine the correlation between ambient PM2.5 and PM10 mass concentrations with cruise ship activities in the Kotor Bay area during 27 days in the peak summer season, with a 10-min resolution. Recorded data and the Openair model were used to investigate the potential relationship between cruise ship operations and temporal fluctuations in PM concentrations in the ambient air. Additionally, an Tier 3 methodology developed through the European Monitoring and Evaluation Programme of the European Environmental Agency (EMEP/EEA) was applied in order to estimate the total cruise ship PM emissions. The study has shown that weather conditions play a significant role in local PM concentrations, so that, with predominant ENE wind directions, the west side of the Bay experienced on average higher concentrations of both PM2.5 and PM10. Rain precipitation and higher winds tend to decrease rapidly ambient PM concentrations. Higher PM levels are associated mainly with lower wind speeds and the inflows from neighboring berths/anchorages. During the maneuvering (arrival and departure) of cruise ships, higher spikes in PM values were detected, being more visible for PM10 than PM2.5. A significant correlation between daily average PM concentrations and cruise ships’ daily estimated PM emission was not found. As a result, higher temporal resolution demonstrated a stronger correlation.
Structural integrity analysis of spherical tank is presented based on use of experimental results, together with the analytical and numerical ones. Analytical calculation of stresses in the scope of ...design process is shortly presented. Numerical analysis was performed by using the Finite Element Method (FEM) to identify areas with high stress concentration, indicating that stress values near supports reach the yield stress. FEM results were verified by the experiment, indicating that it was not necessary to reinforce the spherical tank supports, since its integrity was not jeopardized in normal working conditions. This was also proved by repeating the experiment after 8 months of exploitation.
In mathematics, a conic is the curve that is obtained by intersecting a plane with a cone. Is well known that the shape of this curve may differ quite a bit depending on the position of the ...intersection plane relative to the cone axis, as it is actually a family of curves, commonly called "conical". In the first part, we determine the relation between the shape of the section curve and the angle of the plane of the section plane. The paper also proposes a reassembly of the cone from the fragments resulting from the sectioning with different planes. These recommences can be found as technical solutions for joining two pipes with different diameters and whose axes are not coaxial.
This paper investigates characteristics of metric and density quality of linear object's point-clouds (obtained for horizontal shooting directions) as a function of its inclination angle (measured ...from horizontal plane). Conclusion is that for a fixed focal length, horizontal shooting directions targeting center of object`s axes, 24 station-points uniformly radially distributed around it, Object's Photo-Coverage-Mean of 2.05%, and process-quality descriptors values that belong to recommended ranges, concerning metric quality, generated Clouds are more precise but less accurate and almost not prone to object's inclination; density quality of these Clouds is characterized by precision and accuracy - slightly dependent on object's inclination: the lower the inclination angle, the higher the precision and accuracy; additionally, the lower the inclination, the lower the density.
Accurate calculation of cut and fill volume has an essential importance in many fields. This article shows a new method, which has no approximation, based on Digital Terrain Models. A relatively new ...mathematical model is developed for that purpose, which is implemented in the software solution. Both of them has been tested and verified in the praxis on several large opencast mines. This application is developed in AutoLISP programming language and works in Aut degree CAD environment.
This paper discusses the computational and experimental approach to the determination of aerodynamic coefficients of canard controlled missile with wrap around tail fin. The paper presents results of ...subsonic flow at Mach 0.4. Angle of attack of the missile is varied from -10 to +10 degrees with an increment of 2 degrees. Canard deflection in the pitch plane is also varied at 0, 10, and 15 degrees. The results of the simulation are compared with the experimental data obtained by the wind tunnel measurements. Measured results confirm applicability of Spalart Allmaras turbulence model with adapted computational mesh to the determination of aerodynamic coefficients for canard controlled missiles.
In mathematics, a conic is the curve that is obtained by intersecting a plane with a cone. Is well known that the shape of this curve may differ quite a bit depending on the position of the ...intersection plane relative to the cone axis, as it is actually a family of curves, commonly called "conical". In the first part, we determine the relation between the shape of the section curve and the angle of the plane of the section plane. The paper also proposes a reassembly of the cone from the fragments resulting from the sectioning with different planes. These recommences can be found as technical solutions for joining two pipes with different diameters and whose axes are not coaxial.
In mathematics, a conic is the curve that is obtained by intersecting a plane with a cone. Is well known that the shape of this curve may differ quite a bit depending on the position of the ...intersection plane relative to the cone axis, as it is actually a family of curves, commonly called "conical". In the first part, we determine the relation between the shape of the section curve and the angle of the plane of the section plane. The paper also proposes a reassembly of the cone from the fragments resulting from the sectioning with different planes. These recommences can be found as technical solutions for joining two pipes with different diameters and whose axes are not coaxial.
This paper shows the process of inverting the 4th ordered space curve of the
first category with a self-intersecting point (with two planes of symmetry)
and determining its harmonic equivalent. There ...are harmonic equivalents for
five groups of surfaces obtained through the 4th order space curve of the 1st
category. Mapping was done through a system of circular cross-sections. Both
classical and relativistic geometry interpretations are presented. We also
designed spatial models - a spatial model of the pencil of quadrics and a
spatial model of the pencil of equivalent quadrics. Besides the boundary
surfaces, one surface of the 3rd order, which is an equivalent to a triaxial
ellipsoid, passes through this pencil of surface of the 4th order. The center
of inversion is located on the contour of the ellipsoid. The parabolic
cylinder is mapped into its equivalent, by mapping the contour parabola of
the cylinder, in the frontal projection, in relation to the center and the
sphere of inversion into a contour curve of the 4th order surface. The
generating lines of the parabolic cylinder, which are in a projecting
position and pass through the antipode, are mapped into circles (also in a
projecting position) whose diameters are from the center of inversion to the
contour line. The application of the 4th order surfaces in architectural
practice is also presented.
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