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The purpose of this paper is to investigate propagation characteristics of seismic waves at the welded interface of an elastic solid and unsaturated poro-thermoelastic solid.

A theoretical formulation of partially saturated poro-thermoelastic solid is used in this study established by Zhou et al. (2019). The incidence of two primary waves (P and SV) is taken. The incident wave from the elastic solid induces two reflected waves and five refracted waves. Due to viscous pore fluids, partially saturated poro-thermoelastic solid behave dissipative, whereas elastic solid behaves non-dissipative. As a result, both reflected and incident waves are homogeneous. However, all the refracted waves are inhomogeneous. A non-singular system of linear equations is formed by the coefficients of reflection and refraction for a specified incident wave. The energy shares of various reflected and refracted waves are determined by using these reflection and refraction factors. Finally, a sensitivity analysis is performed, and the effect of critical variables on energy partitioning at the interface is observed. The numerical example shows that throughout the process of reflection/refraction, the energy of incidence is conserved at all angles of incidences.

This study demonstrated two refracted (homogeneous) and five refracted (inhomogeneous) waves due to the incident wave from elastic solid. The reflection and refraction coefficients and partitioning of incident energy are acquired as a part of diverse physical parameters of the partially saturated poro-thermoelastic media. The interference energies between unlike pairs of refracted waves have been discovered due to the dissipative behavior of unsaturated poro-thermoelastic solid.

The sensitivity of different energy shares to various aspects of the considered model is graphically analyzed for a specific numerical model. The energy balance is maintained by combining interaction energy and bulk wave energy shares.

Accurate perception of the environment using range sensors such as laser scanner, SONAR, infrared, vision, etc., for the application, such as path planning, localization, autonomous navigation, simultaneously localization and mapping, is a highly challenging area. The reliability of the perception by range sensors relies on the sensor accuracy, precision, sensor model, sensor registration, resolution, etc. Laser scanner is even though accurate and precise but still the efficient and consistent mapping of the environment is yet to be attained because laser scanner gives error as the extrinsic and intrinsic parameters varied which cause specular reflection, refraction, absorption, etc., of the laser beam. The paper aims to discuss this issue.

This paper presents an error analysis in sensory information of laser scanner due to the effect of varying the scanning angle with respect to the optical axis and surface reflectivity or refractive index of the targets. Uncertainties caused by these parameters are reduced by proposing a new technique, tilt mounting system (TMS) with designed filters of tilting the angular position of a laser scanner with the best possible selection of range and scanning angle for the robust occupancy grid mapping. Various experiments are performed in different indoor environments, and the results are validated after the implementation of the TMS approach with designed filters.

After the implementation of the proposed TMS approach with filters, the errors in the laser grid map are reduced by 15.6 percent, which results in 62.5 percent reduction in the collision of a mobile robot during autonomous navigation in the laser grid map.

The TMS approach with designed filter reduces the effect of variation in intrinsic and extrinsic parameters to generate efficient laser occupancy grid map to achieve collision-free autonomous navigation.

An autonomous mobile robot requires efficient perception of the environment to perform various tasks in a challenging environment. The precise sensory information from the range sensors is required to accomplish prerequisites, such as SLAM, path planning and localization. But the accuracy and precision of the sensors become unreliable in harsh environmental conditions because of the effect of rain, dust, humidity, fog and smoke. The purpose of this paper is to generate robust mapping of the environment in harsh environmental conditions.

This paper presents a novel technique, averaging data with short range selection (ADWSRS), to reduce the effect of harsh environmental (rain, wind, humidity, etc.) conditions on sensory information (range) to generate reliable grid mapping. The sensory information on laser and sonar sensors in terms of probability values (occupied/unoccupied cell) in generating grid maps are fused after passing through two newly designed pre-processing filters: laser averaging filter and short range selection filter. This proposed approach relies on various aspects such as averaging laser data analogous to current pose of the sensor, selection of short range with respect to threshold value to remove the effect of specular reflection/crosstalk of sonar and a newly designed apparatus in which dirt cover (glass cover) and air blower are coupled to remove the influence of dirt, rain and humidity.

This proposed approach is tested in different environmental conditions, and to verify the consistency of the proposed approach, qualitative and quantitative analyses are carried out, which shows 42.5 per cent improvement in the probability value of occupied cells in the generated grid map.

The proposed ADWSRS approach reduced the effect of harsh environmental conditions such as fog, rain and smoke to generate efficient mapping of the environment, which may be implemented in diverse applications such as autonomous navigation, localization, path planning and mapping.

This paper aims to explain and discuss the complex nature and value of knowledge as an exploitable resource for business.

The authors propose a conceptual explanation of knowledge based on three pillars: the plurality of its nature, understood to be conservative, multipliable and generative, its contextual value and the duality of carrier incorporating business knowledge, objects or processes. After conceptualizing the nature of knowledge, the authors offer a metaphor based on the classic transformation from “potential” to “kinetic” energy in an inclined plane assuming that the conservative nature of knowledge makes it act as energy.

The metaphor uses the concept of potential and kinetic energy: if energy is only potential, it has a potential value not yet effective, whereas if the potential energy (knowledge) becomes kinetic energy (products and/or services), it generates business value. In addition, business value is a function of the speed acquired and caused by the angle of inclined plan, namely, the company’s business model. Knowledge is the source of the value and can be maintained and regenerated only through continuous investments. Several years later the value extraction reaches a null value of the company (potential energy) which will cease to act (kinetic energy) for triggering both the value generated and the value extracted.

The paper proposes an initial attempt to explain the meaning of the transformation of knowledge using a metaphor derived from physics. The metaphor of the energy of knowledge clearly depicts the managerial dilemma of balancing a company’s resources for both the generating and extracting value. Similarly, future study should try to associate other knowledge peculiarities to physical phenomena.

The purpose of this research is to study the reflection and refraction of elastic waves at the interface of an elastic half‐space and initially stressed thermoelastic with voids half‐space.

A two‐dimensional model was considered of an isotropic elastic half‐space (medium I) lying over a homogeneous isotropic generalized initially stressed thermoelastic with voids half‐space(medium II). There exist two waves, P‐wave and SV‐wave in isotropic elastic half‐space and three quasi‐longitudinal waves namely, quasi‐longitudinal wave (QP‐mode), quasi‐longitudinal thermal wave (QPT‐mode), quasi‐longitudinal volume fractional wave (QPV‐mode) and one quasi‐transverse wave (QSV‐mode) exists in initially stressed thermoelastic with voids half‐space.

The energy ratios of these waves are computed along various directions of incident wave, and it is found that the sum of all energy ratios is exactly unity at each value of incident angle. The amplitude ratios of various waves were obtained numerically.

Reflection and refraction of an elastic medium is of great practical importance. Since valuable organic and inorganic deposits beneath the earth surface are difficult to detect by drilling randomly, wave propagation is the simplest and most economic technique to these and does not require any drilling through the earth. Almost all the oil companies rely on seismic interpretation for selecting the sites for exploratory oil wells because seismic wave methods have higher accuracy, higher resolution and more economical, as compared to drilling which is expansive and time consuming.

This study aims to explore novel solitary wave solutions of a new (3 + 1)-dimensional nonlocal Boussinesq equation that illustrates nonlinear water dynamics.

The authors use the Painlevé analysis to study its complete integrability in the Painlevé sense.

The Painlevé analysis demonstrates the compatibility condition for the model integrability with the addition of new extra terms.

The phase shifts, phase variables and Hirota’s bilinear algorithm are used to furnish multiple soliton solutions.

The authors also furnish a variety of numerous periodic solutions, kink solutions and singular solutions.

The work formally furnishes algorithms for investigating several physical systems, including plasma physics, optical communications and oceans and seas, among others.

This paper presents an original work using a newly developed Painlevé integrable model, as well as novel and insightful findings.

This study aims at a biometric verification based on facial profile images for mobile security. The modern technology of mobile Internet devices and smart phones such as the iPhone series and Galaxy phone series has revealed the development of information technology of input and output devices as high-definition multimedia interface. The development of information technology requires novel biometric verification for personal identification or authentication in mobile security, especially in Internet banking and mobile Internet access. Our study deals with a biometric verification based on facial profile images for mobile security.

The product of cellphones with built-in cameras gives us the opportunity of the biometric verification to recognize faces, fingerprints and biological features without any other special devices. Our study focuses on recognizing the left and right facial profile images as well as the front facial images as a biometric verification of personal identification and authentication for mobile security, which can be captured by smart phone devices such as iPhone 4 and Galaxy S2.

As the recognition technique of the facial profile images for a biometric verification in mobile security is a very simple, relatively easy to use and inexpensive, it can be easily applied to personal mobile phone identification and authentication instead of passwords, keys or other methods. The biometric system can also be used as one of multiple verification techniques for personal recognition in a multimodal biometric system. Our experimental data are taken from persons of all ages, ranging from children to senior citizens.

As the recognition technique of the facial profile images for a biometric verification in mobile security is very simple, relatively easy to use and inexpensive, it can be easily applied to personal mobile phone identification and authentication instead of passwords, keys or other methods. The biometric system can also be used as one of multiple verification techniques for personal recognition in a multimodal biometric system. Our experimental data are taken from persons of all ages, ranging from children to senior citizens.

One of the recent applications of fabrics is to use them for sound insulation. Accordingly, due to their low production cost and low relative density, fabrics have drawn attention in some of the industries such as the automotive and aircraft industries. The present study is aimed to investigate the effects of the fiber cross-section, porosity, thickness of samples and fuzzing of the knitted fabric on the sound absorption coefficient.

In the present study, fabrics with three different stitch densities were knitted by yarns consist of three different forms of fiber cross-section shapes (circular, elliptical and plus-shaped). In this work, the sound absorption coefficient of knitted fabrics was investigated with regard to the different fiber cross-sections and structural parameters using an impedance tube.

As indicated by the obtained results, the cross-section, porosity, thickness and mass per unit area of the fabrics were the determinant factors for the sound absorption coefficient. In addition to, the sound absorption coefficient and porosity were shown to have an inverse relationship.

A section of the present paper has been allocated to the investigation of the effect of the fiber cross-section and fuzzing of fabric on the sound absorption of plain knitted fabrics.

The behaviour of light in white prints is dominated by the presence of titanium dioxide pigment, which is responsible for opacity. The pigment also strongly influences gloss and is responsible for the whiteness of prints.

The colors of change is an overview of change paradigms, created about two decades ago, that has been intensively used, tested, refined, shared, and elaborated by practitioners and academics alike. Here, the “color theory” is presented as it is now, and is situated within the literature. Its four main applications are described as well as rules of thumb that have been derived from reflective practice. This chapter illustrates that the color theory is clearly not one thing to all people, as it is understood in very different ways, both in terms of its theoretical foundations as well as the complexity of its applications. This probably adds to the versatility of the theory. Bringing together key insights about the color theory for academics and practitioners, this chapter strives both to give a concise overview and to explore its richness.