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The purpose of this study is to design and develop new spiral head projectiles undergoing ballistics impact.
Abstract
Purpose
The purpose of this study is to design and develop new spiral head projectiles undergoing ballistics impact.
Design/methodology/approach
The introduction of the rifled barrel in firearms made projectile spin during its flight path. The central translational velocity (impact velocity) is one parameter to defeat/penetrate the target in the penetration process. Another important parameter considered to be the shape of the projectile. Many types of projectile shapes have been designed to defeat the target. In the recent years, ogival nose shape is one of the well-known projectile shapes in use abundantly. The present research is made to design the nose shape so as to use the spin during the penetration of target effectively. In this study, a new spiral head projectile shape is proposed and designed, which uses the rotation of projectile (spin) for penetrating the Al7075-T6 target. When the ogive and new spiral head projectile is impacted on Al 7075-T6 target of 12.5 mm, 18 mm thicknesses at ordnance velocities, the residual velocity is evaluated numerically using ANSYS/Explicit Dynamics at normal impact condition. Two projectile materials, steel 4340 and tungsten alloy, are used as projectile materials. Along with the translational velocity, rotation velocities (spin rate) 13,000, 26,000 and 52,000 rad/s also provided to projectile. The residual velocities verses spin rate are plotted for different spiral angle projectiles for impact velocities 1,000–1,500 m/s, at normal impact conditions on the Al 7075-T6 target. Compared with the ogive nose projectile, the proposed new spiral head projectile made of tungsten alloy is significantly effective.
Findings
Spiral head projectile having tungsten alloy material gives encouraging results at 12.5 mm target thickness. The new spiral head projectile is damaged partially. At 18 mm target thickness impact conditions, it is observed that the projectile head is completely damaged. The effectiveness of spiral head projectile on a target plate thickness of 18 mm is considered to study the impact condition.
Research limitations/implications
All the above results need to be experimentally verified. However, the basic numerical model used in the present study, i.e. the basic ogive nose numerical model with only translational energy, is well validated with penetration theory available in literatures.
Practical implications
The designed new spiral head projectile is only effective with tungsten alloy material within considered design parameters. For steel 4340 material, the spiral head projectile is less effective than the ogive nose projectile. In tungsten alloy projectiles, by observing all considered spiral angles, 30-degree spiral angle projectile gives the best performance at most of the considered impact velocity conditions.
Originality/value
The proposed research outputs are original, innovative and, have lot of importance in defence applications particularly in arms and ammunitions.
Details
Keywords
Pranay Vaggu and S.K. Panigrahi
The effect of spinning has been studied and analysed for different projectile shapes such as ogive, blunt, cylindrical and conical by using numerical simulations.
Abstract
Purpose
The effect of spinning has been studied and analysed for different projectile shapes such as ogive, blunt, cylindrical and conical by using numerical simulations.
Design/methodology/approach
Projectile shape is one of the important parameters in the penetration mechanism. The present study deals with the failure mechanisms and ballistic evaluation for different nose-shaped projectiles undergoing normal impact with spinning. Materials characterization has been made by Johnson–Cook strength and failure models, and LS-DYNA simulations are used to analyse the impact of steel projectiles on an Al 7075-T651 target at different impact velocities under normal impact conditions. The experimental results from the literature are used to validate the model. Based on the residual velocity values, the Recht-Ipson model has been curve-fitted and approximate ballistic limit velocity has been evaluated. The approximated ballistic limit velocity is found to be 3.4% higher than the experimental results and compared well with the experimental results. Subsequently, the validated model conditions are used to study and analyse the effect of spinning for different nose-shaped projectiles undergoing normal impact conditions.
Findings
The ductile hole failure is observed for the ogive nose projectile, petals are formed and fragmented for the conical projectile, and plugging is observed for cylindrical projectiles. A Recht-Ipson curve is presented for each spinning condition for each projectile shape and the ballistic limit has been evaluated for each condition.
Originality/value
The proposed research outputs are original and innovative and, have a lot of importance in defence applications, particularly in arms and ammunition.
Details
Keywords
Vipin Khattri and Deepak Kumar Singh
This paper aims to provide information of parameters and techniques used in the automated fraud detection system during online transaction. With the increase in the use of online…
Abstract
Purpose
This paper aims to provide information of parameters and techniques used in the automated fraud detection system during online transaction. With the increase in the use of online transactions, the concerns regarding data security have also increased. To tackle the frauds, lot of research has been done and plethora of papers are available on the related topics. The purpose of this paper is to provide the clear pathway for researchers to move in the direction of development of automated fraud detection system to prevent the fraud during online transaction.
Design/methodology/approach
This literature review analyses and compares the different types of techniques for detecting fraud during online transaction. An in-depth study of the most prominent journals has been done and the core methodology of the papers has been presented. This article also shed some light on different types of parameters used in fraud detection techniques during online transaction.
Findings
There are vast varieties of various fraud detection techniques, and every technique has completed task in its own way. After studying approximately 41 research papers, 14 books and four reports, in total 30 parameters have been identified and a detailed study of the parameters has been presented. The parameters are also listed with their details that how these parameters are used in the security system for detecting online transaction fraud.
Research limitations/implications
This paper provides empirical insight about the parameters and their prominence in the development of automated fraud detection security system of online transaction. This paper encourages the researchers to development of improved fraud detection system.
Practical implications
This paper will pave the way for researchers to do a focused research on the fraud detection methodologies. The analysis will help in zeroing down the most prevalent topic of research in this field. The researchers will be able to understand the internal details of parameters and techniques used in the fraud detection systems. This literature also helps the research to think in a variety of ways that how these parameters will be used in the development of fraud detection system.
Originality/value
This paper is one of the most comprehensive reviews in its field. It tries and attempts to fill a void created because of lack of compilation of the laid fraud detection parameters.
Details
Keywords
B.C. Swain, M.R. Panigrahi, S.K. Debroy, J.S. Murty, K.G. Mishra, P.S. Mitra and K.R. Natrajan
Transportation of solids by slurry pipeline is a rapidly growing field. The pipelines, in the process of transportation undergo severe deterioration externally as well as…
Abstract
Transportation of solids by slurry pipeline is a rapidly growing field. The pipelines, in the process of transportation undergo severe deterioration externally as well as internally. Corrosion‐erosion, metal damage caused by the combined action of electrocemical corrosion and mechanical erosion, has been studied extensively. In hydraulic transportation of sand, internal wear is caused by combined action of corrosion, associated with the corrosive water, the flow velocity and abrasion due to geometry of the solid particles on the interior pipe wall. Corrosion in slurry pipeline is generally due to the presence of dissolved oxygen in the slurry. The control of corrosion wear in a coal slurry pipeline is reported by Bomberger. The corrosion study by Postlethwaite and Tinkler showed that the presence of solids in commercial concentration increases the rate of corrosion in pipelines. The most common erosion occurred generally is the scratching or grooving of the pipe by the slurry particles. An erosion‐corrosion study in pilot plant slurry transportation in pipeline carrying wide range of water borne solids such as coal, iron ore and sand have shown that the presence of solids increases the chemical corrosion rate, apart from any accompanying erosion. It was also observed that due to severe corrosion‐erosion problem in pipeline, even a pinhole in such a line would be enlarged gradually in a matter of minutes by the out flow of high pressure abrasive slurry. Jacues and Neil had given an account of the causes, control and the economics of internal corrosion of slurry pipelines Zabell et. al. had studied the effect of bacteria using six different processes on corrosion of iron and the steel water pipes. The copper pipe line had been specially studied by Fischer and few others in various environments.
Roy Poan, Valencya Engla Merizka and Farida Komalasari
The purpose of this study is to examine the role of attitude, religiosity, awareness and subjective norm toward trust which influences purchase intention regarding Islamic…
Abstract
Purpose
The purpose of this study is to examine the role of attitude, religiosity, awareness and subjective norm toward trust which influences purchase intention regarding Islamic insurance in Indonesia.
Design/methodology/approach
This research uses quantitative methods. Online questionnaires are distributed and collected for people who already have an insurance policy, have the knowledge and are interested in buying Islamic insurance in Indonesia. A total of 322 valid responses were collected using non probability purposive sampling and snowball sampling method. To achieve the purpose of this study, an analysis using SEM or structural equation model for hypothesis testing was performed.
Findings
The results show that trust significantly affected purchase intention regarding Islamic insurance. Other than that, trust is significantly influenced by awareness, religiosity and subjective norm. Moreover, the attitude toward trust found that not significantly related.
Originality/value
The originality of this study is the first research integrating attitude, religiosity, awareness and subjective norm, mediating by trust toward a purchase intention of Islamic insurance in Indonesia.
Details
Keywords
Junjie Zhou, Rajiv Kishore, Meiyun Zuo, Ruochen Liao and Xiao Tang
As older adults are increasingly active in virtual communities (VCs), these platforms for knowledge exchange present opportunities for companies to use elder human capital. The…
Abstract
Purpose
As older adults are increasingly active in virtual communities (VCs), these platforms for knowledge exchange present opportunities for companies to use elder human capital. The purpose of this study is to understand the antecedent factors that motivate older adults’ knowledge contribution and knowledge seeking (KS) behaviors in VCs.
Design/methodology/approach
Rooted in socio-emotional selectivity and social cognitive theories, this study included five key variables and developed models for older adults’ knowledge contributing (KC)/KS behaviors. This paper tested the hypotheses using data from a sample of 204 older adults in 3 VCs in China.
Findings
The results provide support for most of the hypotheses and show that while other members’ participation (MP) acts as a substitute for meaning in life and attitude toward aging, it acts as a complement for outcome expectations (OE) focused on others and OE focused on oneself in their impacts on KC/KS activities.
Practical implications
The study provides practical insights for developing elder human resources via VCs to avoid knowledge loss.
Originality/value
This study described older adults’ unique characteristics when modeling their information and communication technologies-related behaviors and built two models to explain their KC/KS behaviors. It confirmed that the same factor has different levels of impact on older adults’ KC/KS behaviors in VCs. In addition, it confirmed and reinforced the complementary and substitutive effects of other MP as an environmental factor on these behaviors.
Details
Keywords
Anahita Farhang Ghahfarokhi, Taha Mansouri, Mohammad Reza Sadeghi Moghaddam, Nila Bahrambeik, Ramin Yavari and Mohammadreza Fani Sani
The best algorithm that was implemented on this Brazilian dataset was artificial immune system (AIS) algorithm. But the time and cost of this algorithm are high. Using asexual…
Abstract
Purpose
The best algorithm that was implemented on this Brazilian dataset was artificial immune system (AIS) algorithm. But the time and cost of this algorithm are high. Using asexual reproduction optimization (ARO) algorithm, the authors achieved better results in less time. So the authors achieved less cost in a shorter time. Their framework addressed the problems such as high costs and training time in credit card fraud detection. This simple and effective approach has achieved better results than the best techniques implemented on our dataset so far. The purpose of this paper is to detect credit card fraud using ARO.
Design/methodology/approach
In this paper, the authors used ARO algorithm to classify the bank transactions into fraud and legitimate. ARO is taken from asexual reproduction. Asexual reproduction refers to a kind of production in which one parent produces offspring identical to herself. In ARO algorithm, an individual is shown by a vector of variables. Each variable is considered as a chromosome. A binary string represents a chromosome consisted of genes. It is supposed that every generated answer exists in the environment, and because of limited resources, only the best solution can remain alive. The algorithm starts with a random individual in the answer scope. This parent reproduces the offspring named bud. Either the parent or the offspring can survive. In this competition, the one which outperforms in fitness function remains alive. If the offspring has suitable performance, it will be the next parent, and the current parent becomes obsolete. Otherwise, the offspring perishes, and the present parent survives. The algorithm recurs until the stop condition occurs.
Findings
Results showed that ARO had increased the AUC (i.e. area under a receiver operating characteristic (ROC) curve), sensitivity, precision, specificity and accuracy by 13%, 25%, 56%, 3% and 3%, in comparison with AIS, respectively. The authors achieved a high precision value indicating that if ARO detects a record as a fraud, with a high probability, it is a fraud one. Supporting a real-time fraud detection system is another vital issue. ARO outperforms AIS not only in the mentioned criteria, but also decreases the training time by 75% in comparison with the AIS, which is a significant figure.
Originality/value
In this paper, the authors implemented the ARO in credit card fraud detection. The authors compared the results with those of the AIS, which was one of the best methods ever implemented on the benchmark dataset. The chief focus of the fraud detection studies is finding the algorithms that can detect legal transactions from the fraudulent ones with high detection accuracy in the shortest time and at a low cost. That ARO meets all these demands.
Details
Keywords
Sanjay Kumar Behera, Dayal R. Parhi and Harish C. Das
With the development of research toward damage detection in structural elements, the use of artificial intelligent methods for crack detection plays a vital role in solving the…
Abstract
Purpose
With the development of research toward damage detection in structural elements, the use of artificial intelligent methods for crack detection plays a vital role in solving the crack-related problems. The purpose of this paper is to establish a methodology that can detect and analyze crack development in a beam structure subjected to transverse free vibration.
Design/methodology/approach
Hybrid intelligent systems have acquired their own distinction as a potential problem-solving methodology adopted by researchers and scientists. It can be applied in many areas like science, technology, business and commerce. There have been the efforts by researchers in the recent past to combine the individual artificial intelligent techniques in parallel to generate optimal solutions for the problems. So it is an innovative effort to develop a strong computationally intelligent hybrid system based on different combinations of available artificial intelligence (AI) techniques.
Findings
In the present research, an integration of different AI techniques has been tested for accuracy. Theoretical, numerical and experimental investigations have been carried out using a fix-hinge aluminum beam of specified dimension in the presence and absence of cracks. The paper also gives an insight into the comparison of relative crack locations and crack depths obtained from numerical and experimental results with that of the results of the hybrid intelligent model and found to be in good agreement.
Originality/value
The paper covers the work to verify the accuracy of hybrid controllers in a fix-hinge beam which is very rare to find in the available literature. To overcome the limitations of standalone AI techniques, a hybrid methodology has been adopted. The output results for crack location and crack depth have been compared with experimental results, and the deviation of results is found to be within the satisfactory limit.
Details
Keywords
Kulmani Mehar and Subrata Kumar Panda
The purpose of this paper is to develop a general mathematical model for the evaluation of the theoretical flexural responses of the functionally graded carbon nanotube-reinforced…
Abstract
Purpose
The purpose of this paper is to develop a general mathematical model for the evaluation of the theoretical flexural responses of the functionally graded carbon nanotube-reinforced composite doubly curved shell panel using higher-order shear deformation theory with thermal load. It is well-known that functionally graded materials are a multidimensional problem, and the present numerical model is also capable of solving the flexural behaviour of different shell panel made up of carbon nanotube-reinforced composite with adequate accuracy in the absence of experimentation.
Design/methodology/approach
In this current paper, the responses of the single-walled carbon nanotube-reinforced composite panel is computed numerically using the proposed generalised higher-order mathematical model through a homemade computer code developed in MATLAB. The desired flexural responses are computed numerically using the variational method.
Findings
The validity and the convergence behaviour of the present higher-order model indicate the necessity for the analysis of multidimensional structure under the combined loading condition. The effect of various design parameters on the flexural behaviour of functionally graded carbon nanotube doubly curved shell panel are examined to highlight the applicability of the presently proposed higher-order model under thermal environment.
Originality/value
In this paper, for the first time, the static behaviour of functionally graded carbon nanotube-reinforced composite doubly curved shell panel is analysed using higher-order shear deformation theory. The properties of carbon nanotube and the matrix material are considered to be temperature dependent. The present model is so general that it is capable of solving various geometries from single curve to doubly curved panel, including the flat panel.
Details
Keywords
Amitava Choudhury, Snehanshu Pal, Ruchira Naskar and Amitava Basumallick
The purpose of this paper is to develop an automated phase segmentation model from complex microstructure. The mechanical and physical properties of metals and alloys are…
Abstract
Purpose
The purpose of this paper is to develop an automated phase segmentation model from complex microstructure. The mechanical and physical properties of metals and alloys are influenced by their microstructure, and therefore the investigation of microstructure is essential. Coexistence of random or sometimes patterned distribution of different microstructural features such as phase, grains and defects makes microstructure highly complex, and accordingly identification or recognition of individual phase, grains and defects within a microstructure is difficult.
Design/methodology/approach
In this perspective, computer vision and image processing techniques are effective to help in understanding and proper interpretation of microscopic image. Microstructure-based image processing mainly focuses on image segmentation, boundary detection and grain size approximation. In this paper, a new approach is presented for automated phase segmentation from 2D microstructure images. The benefit of the proposed work is to identify dominated phase from complex microstructure images. The proposed model is trained and tested with 373 different ultra-high carbon steel (UHCS) microscopic images.
Findings
In this paper, Sobel and Watershed transformation algorithms are used for identification of dominating phases, and deep learning model has been used for identification of phase class from microstructural images.
Originality/value
For the first time, the authors have implemented edge detection followed by watershed segmentation and deep learning (convolutional neural network) to identify phases of UHCS microstructure.
Details