scholarly journals Sniper Rifle Cartridge

2021 ◽  
Author(s):  
Zenon Syroka

The paper proposes a modification of the 7.62 mm NATO rifle cartridge. The design and the results of a computer simulation were presented. The projectile’s flight behavior under different weather conditions was simulated. A figure diagram and a digital model of the projectile were presented. Ballistic calculations were performed, and an animation showing the projectile’s behavior under various weather conditions was developed. The results were patented.

1975 ◽  
Vol 1975 (1) ◽  
pp. 293-300
Author(s):  
R. A. Cochran ◽  
G. A. Manney ◽  
J. P. Fraser

ABSTRACT A computer simulation program has been developed to aid in the evaluation of the oil-spill contingency plans for offshore operations. Using this program, the performance of oil-spill recovery equipment can be simulated as a function of oil-spill size, spill location, and weather. The unique feature of the program is its ability to predict oil recovery as a function of weather conditions. The weather data used consist of the historical wave height frequency distribution and wave height persistence. The oil thickness, which is determined by spreading of the oil, and the wave state determine the performance of recovery equipment. When using the program, oil-spill events and cleanup operations are simulated many times. Each time the weather conditions used in the simulation will be different, owing to the probabilistic nature of weather in the real world and the use of random access to the weather data. In this way a probabilistic estimate of oil recovery is produced for any given oil-spill incident and equipment array. Simulations are presented using state-of-the-art equipment, although the use of improved equipment can be simulated. The results show the need for rapid response and for containment for sudden spills due to the rapid thinning of uncontained oil.


2013 ◽  
Vol 116 (4) ◽  
pp. 497-508 ◽  
Author(s):  
Alien Arias Barreto ◽  
Rita Abalone ◽  
Analía Gastón ◽  
Ricardo Bartosik

2017 ◽  
Vol 24 (1) ◽  
pp. 315-326
Author(s):  
Dorota Jarząbek ◽  
Wiesław Juszkiewicz

Abstract The ability to use computer simulation to predict the behavior of oil spills at sea enables better use of available personnel and resources to combat such spills. The use of oil collecting equipment properly selected to suit the conditions is essential for the operation to be effective. Therefore, an attempt is made to verify the influence of weather conditions on the efficiency of oil recovery. Three types of spilled crude oil were simulated. A relevant experiment was conducted on a PISCES II oil spill simulator.


2011 ◽  
pp. 1554-1576
Author(s):  
Mohamed Marzouk

Construction operations are performed under different working conditions including (but not limited to) unexpected weather conditions, equipment breakdown, delays in procurement, etc. As such, computer simulation is considered an appropriate technique for modeling the randomness of construction operations. Several construction processes and operations have been modeled utilizing computer simulation such as earthmoving, construction of bridges and tunnels, concrete placement operations, paving processes, and coordination of cranes operations. This chapter presents an overview of computer simulation efforts that have been performed in the area of construction engineering and management. Also, it presents two computer simulation applications in construction; earthmoving and construction of bridges’ decks. Comprehensive case studies are worked out to illustrate the practicality of using computer simulation in scheduling construction projects, taking into account the associated uncertainties inherited in construction operations.


Author(s):  
Mohamed Marzouk

Construction operations are performed under different working conditions including (but not limited to) unexpected weather conditions, equipment breakdown, delays in procurement, etc. As such, computer simulation is considered an appropriate technique for modeling the randomness of construction operations. Several construction processes and operations have been modeled utilizing computer simulation such as earthmoving, construction of bridges and tunnels, concrete placement operations, paving processes, and coordination of cranes operations. This chapter presents an overview of computer simulation efforts that have been performed in the area of construction engineering and management. Also, it presents two computer simulation applications in construction; earthmoving and construction of bridges’ decks. Comprehensive case studies are worked out to illustrate the practicality of using computer simulation in scheduling construction projects, taking into account the associated uncertainties inherited in construction operations.


Author(s):  
Nana Pirtskhalava-Karpova ◽  
◽  
Aleksandr Karpov ◽  
Evgeniy Kozlovski ◽  
Mikhail Grishchenko ◽  
...  

Outbreaks of Ips typographus (L.) caused by catastrophic natural phenomena in Central Europe, Siberia and the Far East have been the subject of numerous scientific studies. Molecular methods were used to analyze the relationships and origin of Ips species. The review article shows in detail the biological characteristics of I. typographus, such as the effect of temperature on vital parameters and flight behavior. It was found that the spruce bark beetle disperses within 500 m. However, new attacks occur in the immediate vicinity of the old foci. The susceptibility and protection mechanisms of trees are critical to a successful bark beetle attack. The newly attacked trees react with preformed resin, reactions to wounds, and, ultimately, systemic changes in physiology. The risk assessment in the studies was carried out both at the tree level and at the forest level as a whole. The risk of an attack of I. typographus is associated with the growth of the forest in a particular area, age, the flow of nutrients and water to the tree. The dynamics of outbreaks, to a large extent, depend on the abundance of I. typographus, susceptibility of trees, weather conditions and phytosanitary measures. Bark beetle I. typographus is an integral component of any forest ecosystem. It colonizes weakened, weak or dead trees, and thus begins the decomposition of bark and wood. This pest is able to use short-lived resources and quickly multiply to extremely large numbers, for example, after winds. In such epidemic situations, I. typographus can pose a serious threat to spruce-rich forests, especially for stands planted outside their optimal range. The spatial development of I. typographus infections can be analyzed using GIS and multiple regression methods to investigate potential correlations between climatic, specific and phytosanitary factors and infection dynamics. Also, the article discusses various methods of forest control and emphasizes the need for more sophisticated risk assessment tools.


2011 ◽  
Vol 490 ◽  
pp. 106-118 ◽  
Author(s):  
Ryszard Jasiński

In many machines and devices there are hydraulic drives. They should operate well in various weather conditions, also in low ambient temperatures. Some malfunctions may occur during operation of hydraulic system in a so called “thermal shock condition”, which happens when frozen hydraulic component (e.g. hydraulic pump, motor or directional spool valve) is suddenly supplied with hot oil. Transient thermal state emerges in these conditions. Particular elements of component warm up differently. This results in different thermal expansion of components during warm up, which is changing the size of clearance between cooperating elements. Experimental tests of hydraulic components in low ambient temperatures were conducted in the hydraulic laboratory of the Faculty of Mechanical Engineering of Gdansk University of Technology. They concerned: orbital motors, satellite motors, gear pumps, spool valves (also proportional), piston pumps, and hydraulic cylinders. It was proved, that in thermal shock conditions some malfunctions may occur, especially with large temperature differences between oil and component. Based on results of the tests of hydraulic components and systems start-up in low ambient temperatures, one can perform a change in components design, change the type of material of components elements, and even prepare a proper procedure to be followed during start-up of cold hydraulic components and systems. In the article discusses some designs of hydraulic components resistant to thermal shock, and how to prepare components to work in low temperatures, e.g. by providing system with an additional heater to ensure uniform heating of elements in components. Change in design of hydraulic components resistant to thermal shock conditions can be obtained through computer simulation method. Analytic and computer simulation methods can be used by engineers who design machines and devices that work in low ambient temperatures.


Author(s):  
Kiyomichi Nakai ◽  
Yusuke Isobe ◽  
Chiken Kinoshita ◽  
Kazutoshi Shinohara

Induced spinodal decomposition under electron irradiation in a Ni-Au alloy has been investigated with respect to its basic mechanism and confirmed to be caused by the relaxation of coherent strain associated with modulated structure. Modulation of white-dots on structure images of modulated structure due to high-resolution electron microscopy is reduced with irradiation. In this paper the atom arrangement of the modulated structure is confirmed with computer simulation on the structure images, and the relaxation of the coherent strain is concluded to be due to the reduction of phase-modulation.Structure images of three-dimensional modulated structure along <100> were taken with the JEM-4000EX high-resolution electron microscope at the HVEM Laboratory, Kyushu University. The transmitted beam and four 200 reflections with their satellites from the modulated structure in an fee Ni-30.0at%Au alloy under illumination of 400keV electrons were used for the structure images under a condition of the spherical aberration constant of the objective lens, Cs = 1mm, the divergence of the beam, α = 3 × 10-4 rad, underfocus, Δf ≃ -50nm and specimen thickness, t ≃ 15nm. The CIHRTEM code was used for the simulation of the structure image.


Sign in / Sign up

Export Citation Format

Share Document