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The paper aims to clarify the distribution of excess pore pressure during cone penetration in two-layered clay and its influence on penetrometer resistance.

An arbitrary Lagrangian–Eulerian scheme is adopted to preserve the quality of mesh throughout the numerical simulation. Simplified methods of layered penetration and coupled pore pressure analysis of cone penetration have been proposed and verified by previous studies. The investigation is then extended by the present work to study the cone penetration test in a two-layered clay profile assumed to be homogeneous with the modified Cam clay model.

The reduction of the range of pore pressure with decreasing PF will cause a decrease of the sensing distance. The PF of the underlying soil is one of the factors that determine the development distance. The interface can be obtained by taking the position of the maximum curvature of the penetrometer resistance curve in the case of stiff clay overlying soft clay. In the case of soft clay overlying stiff clay, the interface locates at the maximum curvature of the penetrometer resistance curve above about 1.6D.

The cone penetration analyses in this paper are conducted assuming smooth soil-cone contact.

A simplified method based on ALE in Abaqus/Explicit is proposed for layered penetration, which solves the problem of mesh distortion at the interface between two materials. The stiffness equivalent method is also proposed to couple pore pressure during cone penetration, which achieves efficient coupling of pore water pressure in large deformations.

Despite the many advantages this type of equipment offers, there are still some major drawbacks. Linear cutting machine (LCM) cannot accurately simulate the true rock-cutting process as 1. it does not account for the circular path along which tunnel boring machine (TBM) disk cutters cut the tunnel face, 2. it does not accurately model the position of a disk cutter on the cutterhead, 3. it cannot perfectly replicate the rotational speed of a TBM. To enhance the knowledge of these issues and in order to mimic the real rock-cutting process, a new lab testing equipment was developed by Hyundai Engineering and Construction.

A new testing machine called rotary cutting machine (RCM) is designed to simulate the excavation process of hard-rock TBMs and includes features such as TBM cutterhead, RPM simulation, constant normal force mode and constant penetration rate mode. Two sets of tests were conducted on Hwandeung granite using different disk cutter sizes to analyze the cutting forces in various excavation modes. The results are analyzed using statistical analysis and dimensional analysis. A new model is generated using dimensional analysis, and its results are compared against the results of actual cases.

The effectiveness of the new RCM test was demonstrated in its ability to apply various modes of excavation. Initial analysis of chip size revealed that the thickness of the chips is largely dependent on the cutter spacing. Tests with varying RPM showed that an increase in RPM results in an increase in the normal force and rolling force. The cutting coefficient (CC) demonstrated a linear correlation with penetration. The optimal specific energy is achieved at an S/p ratio of around 15. However, a slightly lower S/p ratio can also be used in the design if the cutter specifications permit. A dimensional analysis was utilized to develop a new RCM model based on the results from approximately 1200 tests. The model's applicability was demonstrated through a comparison of TBM penetration data from 26 tunnel projects globally. Results indicated that the predicted penetration rates by the RCM test model were in good agreement with actual rates for the majority of cases. However, further investigation is necessary for softer rock types, which will be conducted in the future using concrete blocks.

The originality of the research lies in the development of Hyundai Engineering and Construction’s advanced full-scale laboratory rotary cutting machine (RCM), which accurately replicates the excavation process of hard-rock tunnel boring machines (TBMs). The study provides valuable insights into cutting forces, chip size, specific energy, RPM and excavation modes, enhancing understanding and decision-making in hard-rock excavation processes. The research also presents a new RCM model validated against TBM penetration data, demonstrating its practical applicability and predictive accuracy.

Pretreatment of fabric with a number of chemicals and auxiliaries is a prerequisite for inkjet printing. Owing to the rapidly increasing use of inkjet printing for textile fabrics, the study of the effects of process variables on various characteristics of the resulting print has drawn considerable interest recently. The purpose of this paper is to study the effects of different variables associated with the inkjet printing process on the quality of the resulting print. Specifically, the effects of chemicals and auxiliaries used in the pretreatment of the fabric prior to printing and factors such as steaming time were studies.

In the present study, which forms a part of a larger study by the authors, the influence of the nature of thickener, the amounts of thickener, urea and alkali, pH of the pretreatment liquor and the duration of steaming on ink penetration into the printed fabrics and the ink spreading across the fabrics was studied. The nature of ink penetration and ink spreading are known to have pronounced effects on the quality and, in turn, the overall appearance of the resulting print. A set of experiments based on a blocked 2^5–1 fractional factorial design with four centre points were conducted to evaluate the role of the aforementioned five variables. Ink penetration was quantified on the basis of the principles of Kebulka-Munk theory while ink spreading was analysed by image analysis.

Detailed statistical analyses of the experimental data obtained show that different thickeners perform differently and can have a marked influence on ink penetration and ink spreading. In the case of polyacrylic acid-based thickener, changing the levels of the factors has a marked effect on ink penetration and in-turn on ink spreading. In the case of polyacrylamide (PAM)-based thickener, on the other hand, the effect of changing the levels of various factors on the ink penetration and ink spreading is considerably less pronounced. In addition, PAM treated samples exhibited better performance in terms of ink penetration and spreading.

This study provides useful information for textile printers and highlights the importance of selecting the right type of thickener to make the printing process and the quality of the resulting print more predictable and controllable.

The development in information communication and technology (ICT) has led to many changes such as reorganization of economics, globalization and trade. With more innovation processes being organized and adopted across technologies, trade, etc., these are getting more closely related and needs fresh research perspective. This study aims to empirically investigate the interrelationship between ICT penetration, innovation, trade and economic growth in 20 developed and developing nations from 1995 to 2018.

The present paper examines both long-run and short-run relationships between the four variables, namely, innovation, ICT penetration, trade and economic growth, by applying panel estimation techniques of regression and vector error correction model. ICT penetration and innovation indices are constructed using principle component analysis technique.

The findings of the study highlight that for developed nations, growth, trade and innovation are significantly interlinked with no significant role of ICT penetration While for developing nations, significant relationship is present between growth and trade, ICT penetration and innovation. With respect to trade, in case of developed nations, significant relationship is present with ICT penetration. While for developing nations there is no significant result for trade promotion. On further employing the vector error correction model, the presence of short run causality between growth, trade and innovation in case of developed nations is established but no such causality between variables for developing nations is seen.

The present paper adds to the existing strand of literature examining interlinkage between innovation and growth by introducing new variables of ICT penetration and innovation.

This paper aims to investigate the effects of fragment impacts to shaped charge warheads in terms of shaped charge jet formation geometries and penetration performances.

In experimental process, a fragment was accelerated to a shaped charge warhead by means of a powder gun to a velocity more than 1,000 m/s, and this impact led to conical damage in the explosive of the warhead. Deformation on the warhead was visualized using X-ray technique to observe holes generated during fragment impact. Penetration test was performed against AISI 1040 steel plates with the damaged shaped charge warhead. Penetration performance of shaped charge jet, which deviated from the symmetry axis, was simulated by using SPEED software with 3-D Eulerian method to validate the numerical modelling method by comparing penetration test and simulation results of damaged warhead.

Simulation and test results showed good correlation for the warhead in terms of penetration depth and hole geometry at the impact surface of steel plates. In addition, the effects of the numbers and the geometries of fragment holes on shaped charge jet penetration performances were investigated with validated numerical methods. Simulation results showed that the increase in the number of fragment holes in the explosive of the warhead led to particulation of shaped charge jet that diminished penetration depth in the target plate. Additionally, simulation results also showed that the fragment hole geometry in the explosive after different fragment impact angles affected the amount of jet deviation from the symmetry axis as well as penetration depth in the target plate.

The results obtained from the current study revealed that fragment impact angle and different number of fragment impact reduced the penetration performance of shaped charge warhead by influencing the symmetry of shaped charge jet negatively.

The current study fulfils the need to investigate how fragment impact on the shaped charge warhead affect the formation symmetry of shaped charge jet as well as penetration performance by experimental and numerical methods. Penetration performance result of asymmetric jet is compared by experimental and numerical studies. A detailed methodology on numerically modelling of the effect of fragment impact angle and number of fragment impact on shaped charge jet performance is given in this study.

Granular material exhibits rich dynamical behaviors under impacting, and its impacting dynamical process is seriously influenced by many factors. The purpose of this paper is to explore the dynamical response of granular bed obliquely impacted by a rotational projectile, and the effect of density ratio and diameter ratio on its penetration depth is mainly considered.

In most experiments, as the angular velocity and the impact velocity always produce a coupling effect on the whole impact process, then it is quite difficult to separately distinguish the influence of angular velocity. Therefore, the discrete element method is used here to achieve this purpose. The authors vary one parameter and keep other parameter unchanged, and then discuss the effect of these parameters on penetration depth statistically.

The numerical model in this paper can effectively predict the dynamical process of granular medium under impacting. The projectile’s penetration depth exhibits a similar scaling with its angular velocity under different density ratios and diameter ratios, and the angular velocity exhibits an obvious criticality.

A DEM code and corresponding statistical approach are used to explore the complex dynamical process of a granular material obliquely impacted by a rotation projectile.

Examines the penetration of television advertising in relation to the qualitative contents; continuity of the advertising; exposure patterns; and whether or not the advertising is for a new product. Results were found that advertisements with positive cognition and/or effect achieved deeper penetration than those with negative such. It was also found that series advertising using the same spokesperson and/or the same tone of appeal achieved deeper penetration than non‐series advertising and that penetration began to reach saturation by non‐series advertising earlier than by series advertising. Long‐term exposure raised its penetration level when its frequency of contact increased. Short‐term exposure made penetration begin to reach saturation earlier than long‐term exposure. Further, it was found that advertising for existing products achieved deeper penetration than advertising for new products.

The purpose of this paper is to present an efficient algorithm for multi-layer garment fitting simulation based on the geometric method to solve the low time cost problem during penetration detection and processing. This is more practical to design a CAD system to preview the multi-layer garment fitting effect in daily life.

The construction of a multi-layer garment based on existing 3D garments is a suitable method because this method is similar to the daily method of multi-layer dressing. The major problem is the penetration phenomenon between different garments because these 3D garment’s geometric shapes are constructed in different situations. In this paper, an efficient algorithm of multi-layer garment simulation is reported. A face-face intersection detection algorithm is designed to detect the penetration region between multi-layer garments fast and a geometric penetration processing algorithm is presented to solve the penetration phenomenon during multi-layer garment simulation.

This method can quickly detect the penetration between faces, and then deal with the penetration for multi-layer garment construction. Experimental results show that this method can not only remove the penetration but basically maintain the trend of wrinkles efficiently. At the same time, the garments used in the experiment have almost more than 5,800 faces, but the resolving time is under five seconds.

The main originalities of the multi-layer garment virtual fitting algorithm based on the geometric method are highly efficient both in terms of time cost and fitting effect. Based on this method, the technology of multi-layer garment virtual fitting can be used to design a novel CAD system to preview the multi-layer garment fitting effect in real time. This is a pressing requirement of virtual garment applications.

The explosion of mobile telephony in recent times has led to the emergence of a significant volume of literature. One area that has been relatively under-researched has been the role of mobile telephony in impacting economic growth and the relevance of financial inclusion in this respect. Using data on MENA countries during 2001-2012, this paper aims to examine this issue within an empirical framework.

The analysis is based on longitudinal data for the period 2001-2012 and examines the interrelationships among per capita income, financial inclusion and mobile telephony. To take on board this interrelationship, the authors use a simultaneous equation model. In contrast to the ordinary least squares, 3SLS exploits the information that the disturbance terms in the two structural terms are contemporaneously correlated, thereby producing consistent estimates.

The analysis suggests a significant relationship among these variables. In particular, a 1 per cent increase in the fraction of population using mobile telephony improves incomes by roughly 0.3 per cent points, whereas a similar 1 per cent increase in financial inclusion has double the impact on income. The findings also support a convex, non-linear relationship between income and cellular penetration. Robustness tests lend credence to these findings.

Although there are several studies on mobile telephony and growth, this paper provides a completely original contribution in the area of financial inclusion, linking the development of access to mobile communication to new channels for the unbanked population in the Arab economies.

Surgical gown fabrics are categorized for liquid penetration resistance by standard tests under specified laboratory conditions, which can be different from the conditions encountered in the surgical environment. The purpose of this paper is to examine the influence of temperature and challenge liquid (CL) type on the effectiveness of liquid penetration resistance of surgical gown fabrics.

One disposable and one reusable surgical gown fabric were tested for liquid penetration using standard methods required in American Society for Testing Materials F2407 for classifying the materials used in Levels 1‐3 surgical gowns. Standard test conditions were compared to varied conditions of ambient/fabric temperature (AFT), CL type and challenge liquid temperature (CLT). Analysis of variance was used to determine the effects of variables on liquid penetration.

AFT, CL type and CLT were significant (p<0.05) variables for liquid penetration for at least one of the test fabrics. Higher ambient temperature, fabric and liquid temperature conditions resulted in greater liquid penetration. Use of synthetic blood as the CL resulted in higher liquid penetration than observed with distilled water.

Results suggest that temperatures within the range of body heat or ambient surgical environments are sufficient to affect liquid penetration of surgical gown fabrics. Also, the use of CLs other than distilled water and the use of CLs warmed to body temperature may be needed to accurately assess the liquid penetration resistance of surgical gown fabrics. Level of protection afforded by surgical gowns may be compromised by variability in these conditions.

Conventional wisdom has held that differences between standard testing temperatures and body temperature or ambient temperature in the surgical theatre were insufficient to influence liquid penetration. This study has shown otherwise. No previous studies were found that addressed these variables but our study illustrates their effect on selected materials.