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Copyright of Research & Exploration in Laboratory is the property of Research & Exploration in Laboratory and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Journal of Harbin Institute of Technology. Social Sciences Edition / Haerbin Gongye Daxue Xuebao. Shehui Kexue Ban is the property of Harbin Institute of Technology and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Transactions of the Chinese Society of Agricultural Engineering is the property of Chinese Society of Agricultural Engineering and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Transient miniaturized antenna is a hoi topic in antenna technology research. For the application ol shaped metal jets in miniaturized antennas, a research method combining theoretical analysis and numerical simulation is used. ϕl50 mm conical shaped charge is taken as research object, a dipole antenna formed by a shaped metal jet antenna is theoretically analyzed, and the applicability of the shaped metal jet antenna to the charge structure and explosive material is numerically studied using finite element software LS-DY.NA. The results show that the metal jet antenna formed by shaped charge meets the characteristics of transient miniaturization and has the length, continuity and good interface matching with the wavelength. The shaped metal jet needs to have a certain length and body when it is used as an electromagnetic pulse radiating antenna, larger gain can be obtained with a transition between the jet diameter and the slug diameter and the small change in the slug. The input impedance is minimized when the metal jel is not fully formed. The metal jet formed by ihe small cone angle cover better meets the antenna requirements. When llie thickness of liner is 2. 1 -2. 3 mm, the length of ihe formed metal jet antenna is the largest, and there exists an extreme value of radiation frequency. The forming velocity of jel arilenna due to B-explosive charge exploding is greater than that of the JII-2 and TNT, and the B-explosive charge explodes to produce a metal jel with the best fracture lime, the largest slug radius is moderate, and the longest antenna length is available at the lime of fracture. When used as an antenna, the radiated frequency range is the largest and is more suitable for use as a shaped metal jel antenna. [ABSTRACT FROM AUTHOR]

A numerical simulation model for ceramic target impacted by long-rod projectile (LRP) is established to investigate the influence of several factors on the interface defeat of ceramic armor by using finite element software AUTODYN. The reliabilities of parameters and algorithms of simulation method are verified. The main factors, such as LRP nose shape, cover plate and pre-stress of ceramics, are simulated in two-dimensional computational studies. The simulated results show that three nose-shapes of LRP have significant effects on interface defeat/penetration transition velocity. The degree of damage on the ceramic can be decreased and the interface defeat/penetration transition velocity can be improved by adding a cover plate and applying a pre-stress on ceramic. [ABSTRACT FROM AUTHOR]

Bused on projectile-largel separation method, numerical simulation method of 3D deformable travelling projectile penetrating into a prc-drillcd target is proposed by using Forrcslal semi-empirical re­sistance via user subroutine of ABAQUS. The reliability uf user subroutine and simulation model is veri­fied. The influences of offsetting, incidence angle and angle ui attack on trajectory are unulyzcd. The re­sult show that Any inflnpiipf factor affects the trajectory and penetration depth. The pie drilled hole on target haft significant oriented effect for the penetration of travelling projectile. Under the combined influ­ence of offsetting, incidence angle and angle of attack, the pre-drilled hole on target has limitation in ori­ented function and a ricochet may occur under the condition of extreme imparl. [ABSTRACT FROM AUTHOR]