Estimating camera parameters from starry night photographs

We propose an efficient, specific method for estimating camera parameters from a single starry night image. Such an image consists of a collection of disks representing stars, so traditional estimation methods for common pictures do not work. Our method uses a database, a star catalog, that stores the positions of stars on the celestial sphere. Our method computes magnitudes (i.e., brightnesses) of stars in the input image and uses them to find the corresponding stars in the star catalog. Camera parameters can then be estimated by a simple geometric calculation. Our method is over ten times faster and more accurate than a previous method.

Features of geometric design of planetary rotary hydraulic machines with satellite stands

А method of geometric calculation of a new type of planetary rotary hydraulic machines (PRGM) with satellite stands is developed. The method includes the steps of: 1) calculation of the initial round-link mechanism; 2) calculation of non-round links of the PRGM with outstretches; 3) construction and integration of three-dimensional design system COMPAS-3D fragments of crenellated crowns corresponding to the phases of abutments and lifting-lowering satellites; 4) correction of the toothed contours to eliminate the phenomenon of mismatch of satellite centers with the points of intersection of the trajectories of these centers in their movement relative to the rotor and stator. PRGM with satellite stands are designed to operate as vacuum pumps, compressors and pneumatic motors.

GEOMETRIC CALCULATION OF THE PLANETARY MECHANISM WITH THE EQUAL NUMBER OF TEETH OF THE EXTERNAL AND INTERNAL SUN GEAR

The article proposes a method for geometric calculation of gear links of planetary mechanisms in which the central wheels of external and internal gearing have the same number of teeth. The key to solving the problem is the existing possibility of a large positive displacement of the tool when machining the crown with internal involute teeth. The calculation used the formulas GOST 16532–70 and GOST 19274–73, arranged in a certain sequence. The planetary mechanisms under consideration underlie the new volumetric rotary hydraulic machines.

Multiple Reflections Modeling for Multi-Layered Optical Structures

Fresnel equations and transfer matrix approach are usually employed to solve for exact solution to Maxwell’s equations for multi-layered optical structures. In this paper, we demonstrate that the Fresnel equations and transfer matrix approach can be expanded using Geometric series. This geometric series give an insight to how the light is trapped and behaves in multi-layered optical structures. It also allows us to calculate multiple reflections and count the number of round-trip inside the structure. One main issue in optical calculation is that layers are usually treated as an infinitely large layer. This is, of course, not practical in term of device fabrication. We also demonstrate how this simple geometric calculation will enable us to calculate a smallest practical size that can accommodate a required optical resonant effect.

Employing Incremental Outlines for OpenStreetMap Data Updating

The updating of changing information plays a significant role in ensuring the quality of OpenStreetMap, which is usually completed by mapping the whole changing objects with a high degree of uncertainty. The incremental object-based approach provides opportunities to reduce the unreliability of data, while challenges of data inaccuracy and redundancy remain. This paper provides an incremental outline-based approach for OpenStreetMap data updating to solve this issue. First, incremental outlines are delineated from the changed objects and distinguished through a spatial classification. Then, attribute information corresponding to incremental outlines is proposed to assist in describing the physical changes. Finally, through a geometric calculation based on both the spatial and attribute information, updating operations are constructed with a variety of rules to activate the data updating process. The proposed approach was verified by updating an area in the OpenStreetMap datasets. The result shows that the incremental outline-based updating approach can reduce both the time and storage costs compared to incremental objects and further improve data quality in the updating process.

The Expert Choice Implementation in Selecting the Electronic Voting Software

The voting service process conducted today is still done manually so that it becomes a decision to utilize the electronic voting. The electronic voting greatly reduces human control and human direct influence on this voting process. Problems faced by end users in the selection are there are so many choices of electronic voting software. Decision making, essentially a form of election of the various alternatives of action or multi-criteria decision making that can be selected. Decision support system in this research is used to select the type of electronic voting software. The method used in this research is the multi criteria decision making and analytical hierarchy process using expert choice software. And aims to make decisions that can make certain parties to take the best decision in choosing the type of electronic voting software. From the data processing is concluded that the first sequence is online voting 58.3%, express vote 17.2%, simply voting 17% and ballot online 7.5%. Processing of data obtained from the respondent expert inconsistencies value ratio is less than 0.1, thus the combined geometric calculation result data is fairly consistent.