Joint Strike Research Articles

Research on Communication Stability of Inter-Cannonball Network Based on OPNET

In modern warfare, achieving strikes against military targets commonly involves utilizing methods such as fire coverage and missile precision guidance. While effective, fire coverage requires significant ammunition support, and missiles can be costly. Therefore, an intelligent strike solution can be an effective way to address these challenges. The inter-cannonball wireless communication network provides a solid foundation for inter-cannonball networking and joint strikes. The synergy improves the strike’s range and precision, ensuring own safety and destroying the enemy’s core with success. In this paper, the reliability of inter-cannonball group communication is studied. The vast array of activities and short striking distance of cannonballs make wireless networking between cannonballs a technological challenge. For this unique communication environment, the network of cannonballs is discussed, the self-organizing structure model of the network is proposed, the corresponding node topology is established, the protocol framework of inter-cannonball communication is presented, and the simulation parameters of the communication network are set. On this premise, discrete event simulation is performed by using the OPNET program to validate the impact of failure rate and node movement speed on the inter-cannonball network communication reliability. And the main performance indices of the inter-cannonball communication system are derived. The simulation results indicate that it can maintain basic communication stability, with wireless LAN delays of less than 100 ms, even when the node failure rate reaches 20%. The simulation verification method, on the other hand, overcomes the limitations of the real environment, optimizes the design phase, reduces research costs, and accelerates the development of intelligent cannonballs.

Remote Sensing Data Integration of Landsat 8 and SRTM for Geomorphological Characteristics Identification in Karst Pringkuku, Pacitan, East Java

Pringkuku is one of the transition areas where the morphology of karst began to develop toward the western part of Gunung Sewu Karst region. The purpose of this research is to identify the landform unit in Pringkuku’s Karst as the result of geomorphological processes recorded by Landsat 8 image and SRTM image. The research was conducted by analyzing and dividing the landform units based on landform parameters such as flow patterns, slope forms, valley forms, and ridge patterns. Structural geology data such as a strike of joints and direct rock sampling are also used as the supporting data. The developing flow patterns are the multi-basinal and rectangular patterns in the western and eastern parts of the area respectively. Inferred from the analysis of joints pattern and stream lineament, the rectangular pattern is in direction NW - SE and NE - SW. The results of this research are two units of karst and structural landform, which are structural limestone hill unit in the eastern part of the area with 68.18% of spreading area of the total extent and conical limestone hill unit in western part of the area with spreading area of 31,82%.

Structural planes surveying and fractal dimension characteristics of tunnel face based on digital photogrammetry

Based on the digital photogrammetry, technical operation standards, such as the layout of the controlling points and optimization of shooting area, and some technical essentials have been proposed. Thus, the tunnel excavation contour and joint parameters can be obtained rapidly and accurately without interfering with tunneling operations. For practical tunnel engineering, the three-dimensional models of 62 tunnel working faces have been established, and then the overbreak and underbreak data and the joint parameters have been collected by Siro 6.0, an artificial-intelligent interaction platform. Based on the statistical self-similarity of tunnel section contour and the method of box dimension, the relationship between the fractal dimensions and the surrounding rockmass classifications, orientation, joint spacing, and included angle between joint strike and tunnel axis has been analyzed. The result shows that the fractal dimension reduces with decrease of the surrounding rockmass classification. When the joint spacing is fixed, the fractal dimension shows exponential decay with the increase of included angle between joint strike and tunnel axis. When the angle is fixed, the fractal dimension decreases with the increase of joint spacing. For the surrounding rockmass of classification III, the relationship between the fractal dimension and joint dip angle is approximately normally distributed and the fractal dimension reaches the maximum value as the joint dip angle ranges from 35° to 55°. In addition, the fractal dimension decreases linearly with the increase of joint spacing, presenting two segments divided by the intersection with joint spacing equal to 32.65 cm.

Into the black box? Technology sharing in major arms transfers and beyond

From the recipients’ perspective, arms transfers have, through the use of offsets, technology transfers, and industrial participation, become an opportunity to receive not only advanced weapons, but also technologies not otherwise available. How important are friendly relations for securing a military export order? To what extent do buyers demand advanced military or commercial technology and how are these demands accepted by the supplier? How does this influence smaller producers in relation to major producers? These questions are addressed by studying (a) the Joint Strike Fighter/F-35 by Lockheed Martin, USA, and the JAS-39 Gripen aircraft by Saab, Sweden, (b) the Medium Multi-Role Combat Aircraft competition in India for 126 combat aircraft, and (c) the Indian offset policy. In the final section, some long-term consequences are discussed.

Morphometric analysis and its relation to tectonics in Macaronesia

For an investigation of the relation between the morphology and the tectonics in the Macaronesian Islands (i.e. the geographical group of middle Atlantic Islands between 10°N and 40°N), orientation studies have been made of steeply dipping joints and, where possible, of the trends of valleys and ridges. A coincidence of the “preferred directions” of these features indicates a probable genetic relation between them. The results are: (1) Joint strikes, stream directions and ridge trends (where available) generally agree with each other on each individual island, indicating a common genetic (tectonic) origin of these features. Thus, the main result of this study is that the morphology of all Macaronesian Islands, although surficially of volcanic origin, has been significantly codesigend by tectonic processes. (2) The direction data for corresponding geomorphic features are essentially the same across each individual archipelago, certainly with regard to the joints, somewhat less so with regard to the links and ridges. (3) The Canary and the Madeira Islands Archipelago yield the same values for the direction maxima of joints and streams. (4) The compression ( σ 1)-axis indicated by the fault plane solution of the Canary earthquake of 9 May 1989 lines up with one of the bisectrices and not with one of the strike-maxima of the surrounding joints; this indicates that the joint directions may be indicative of the shear lines rather than of the principal stress directions of the neotectonic stress field in the area. (5) There is a steady anticlockwise rotation of corresponding morphotectonic directions as one moves from Africa westward from the Canary Islands through Madeira and the Cape Verde Islands to the Azores. This may be due to a general rotation of the area: whilst drifting N, Africa has been subject to an anticlockwise rotation (pole west of Madeira) owing to the drag caused by the eastward-spreading Atlantic Ocean floor. (6) The mid-Atlantic ridge seems to have no influence on the orientation of the joints/streams/ridges on the islands. In the plate-tectonic model, this lining up of joint orientations may be the consequence of the mirror reflection of the displacements away from the Ridge on its two sides. (7) The situation at the triple junction of the Eurasian, African and American plates is not clear; additional microplates (Azorean, Iberian) might even be present. The Azores might (i) have arisen around the triple junction from basaltic lava upwelling from a mantle hot spot to be carried away as islands on the moving plates; or (ii) they may represent a hot-spot trace on moving plates. Since trachytic/andesitic lava flows have been found on the islands, (iii) a tectonic control model has been proposed in the literature without recurrence to basaltic plates. The results of our morphometric studies would be able to conform to all three models.

Joint strike: Missiles and aircraft in long ‐ range land attack

Joint strike: Missiles and aircraft in long ‐ range land attack

Structural controls on the orientation of erosion gullies in mid-western New South Wales, Australia

The role of geology in determining the drainage network of gullying has been evaluated by quantitative methods of analysis. At gully erosion sites in New South Wales, field evidence suggests that soil cracks are sites of preferential flow and erosion at both the surface and subsurface. Soil fabric and rock structure and weathering studies were undertaken to establish the inheritance of soil cracks from the underlying parent material. Gully orientation was correlated with the strike of joints and bedding planes in a range of rock materials, including sedimentary, intrusive and extrusive igneous, and thermal and regional metamorphic rocks. These units vary not only in terms of mineralogy but also in degree of weathering. However, all are steeply dipping structures (usually exceeding 60°). Correlations exist between gully orientation and joints in the underlying material, but the strength of the relationship varies according to the parent material. In the Ordovician hornfels, where no correlation between joints and gully orientation occurred, the evidence showed that gullying was controlled by faulting along the hornfels–granite boundary. These relationships support the view that throughflow processes are dominant in the development of gullies, since convergence of runoff would not be expected to align with subsurface soil discontinuities.

Breakage assessment through cluster analysis of joint set orientations of exposed benches of opencast mines

This paper substantiates, through three different case studies, that the breakage assessment of opencast bench blasting can be made scientifically through the analysis of joint set orientations of different exposed benches in association with the corresponding face direction. Joint orientations, dip and strike of bedding planes have a significant influence on rock breakage. They can have decelerating effects on blasting performance, which may be rectified by geological mapping, and subsequently modifying the blast design parameters.

Delineating a Subsurface Fracture System in A Petroleum Reservoir-An Experiment

The use of a multisensor array has shown that hydraulic pressurization can be useful in delineating subsurface fracture systems in petroleum reservoirs. It can help in establishing effective patterns of injection and production wells to avoid premature waterfront break-through, and thus increase sweep efficiency and oil recovery in flooding operations. Introduction Well stimulation by hydraulic fracturing is often a prerequisite to effective oil recovery by prerequisite to effective oil recovery by waterflooding, but acceptance of this idea has been inhibited by fears that fractures would permit channeling of the displacing fluid and bypassing of oil. Donahue et al. conducted model studies of a five-spot pilot flood and found that different orientations of the pattern significantly affected the sweep efficiencies at pattern significantly affected the sweep efficiencies at breakthrough (Fig. 1). Others report that consideration must be given to the type of fracture to be formed and to the presence of natural fluid conduits in the subsurface formation of the reservoir. Hubbert and Willis, Heck, Kehle, and Dunlap report that induced fractures will be vertical and will extend in a compass direction usually dictated by the earth stresses. Their studies show that the most probable direction that will be assumed by induced fractures can be estimated with some accuracy from a study of the principal horizontal tectonic stresses. However, communication between wells or between zones and the direction of magnitude of natural fracture trends must also be delineated . The pattern of injection and production wells can then be established to make maximum economic use of the subsurface natural and induced fracture system. For the Appalachian area, considerable data have been obtained from surface studies of joints and lineaments on the direction preferred by induced hydraulic fractures and on orientation predictions. This seems to confirm the work of Heck who concluded earlier that reservoir rocks and surface rocks are jointed similarly, except that the subsurface joints are relatively closed and exist as planes of weakness. We shall describe here a field experiment designed to establish a technique for delineating the subsurface fracture system in a petroleum reservoir. Essentially, the procedure employed is an interference test that was modified by the addition of a multisensor array of pressure transducers to measure responses simultaneously and at considerable distances from the test well. The test site is adjacent to leases where joint and lineament strikes, directional permeability, and the orientations of induced hydraulic fractures were measured in the manner described by Anderson and Stahl. We shall describe the instrumentation and tests that were employed, and interpret the fracture trends from this field experiment. The Bradford Test Site Description and Location A 36-acre tract about 10 miles east of Bradford, Pa., was made available for this research by the Minard Run Oil Co. (See Fig. 2.) Open-hole completion practices were used and considerable subsurface data were practices were used and considerable subsurface data were available in the form of cores, electric logs, and wellbore impression-packer surveys. The orientation of induced hydraulic fractures was compared with surface joint measurements.