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The purpose of this paper is to extract the angle information of direct P wave within multidimensional vibration signals obtained through the sensor array, and to realize high precision shallow burst point localization based on direct of angle (DOA).

This paper presents a method which combines adaptive covariance matrix (ACM) algorithm with geometric constraint conditions for extracting the angle information of direct P wave by using its polarization characteristics. First, modify the obtained three-dimensional vibration data by using attitude rotation matrix and unify the coordinate system of vibration field. Next, construct the beam model of direct P wave by making use of ACM algorithm and extract its angle information. Finally, modify P wave beam model by taking advantage of the space geometric constraint relations between nodes.

The results of numerical simulation show that this method not only can extract the angle information of direct P wave arriving at each node effectively, but also can evaluate the quality of extracted angle information of direct P wave. Meanwhile, the results of underground shallow explosion experiment show that this method can extract the angle information of direct P wave of each node significantly and can realize underground shallow explosion source localization based on DOA by using this information, the location error can be limited less than 50 cm and satisfies the location requirements of shallow burst point.

This paper provides a method for various problems of underground localization based on the sensor array, such as directional demolition blasting, underground damage assessment, earth-penetrating projectile burst point positioning in weaponry industry testing plant, etc., and has definite value to engineering application in underground space positioning field.

The purpose of this paper is to solve the problem that the location of the initiation point cannot be measured accurately in the shallow underground space, this paper proposes a method, which is based on fusion of multidimensional vibration sensor information, to locate single shallow underground sources.

First, in this paper, using the characteristics of low multipath interference and good P-wave polarization in the near field, the adaptive covariance matrix algorithm is used to extract the polarization angle information of the P-wave and the short term averaging/long term averaging algorithm is used to extract the first break travel time information. Second, a hybrid positioning model based on travel time and polarization angle is constructed. Third, the positioning model is taken as the particle update fitness function of quantum-behaved particle swarm optimization and calculation is performed in the hybrid positioning model. Finally, the experiment verification is carried out in the field.

The experimental results show that, with root mean square error, spherical error probable and fitness value as evaluation indicators, the positioning performance of this method is better than that without speed prediction. And the positioning accuracy of this method has been improved by nearly 30%, giving all of the three tests a positioning error within 0.5 m and a fitness less than 1.

This method provides a new idea for high-precision positioning of shallow underground single source. It has a certain engineering application value in the fields of directional demolition of engineering blasting, water inrush and burst mud prediction, fuze position measurement, underground initiation point positioning of ammunition, mine blasting monitoring and so on.

The purpose of this paper is to propose a new method to achieve omni-directional vibration vector signal acquisition, and use this method to improve the accuracy of the underground explosion point localization.

Following an introduction, this paper describes the design principle of a sensor structure, and discusses the rationality of the spherical structure of the sensor through finite element analysis. The sensor prototype is designed according to the above method, and its performance is tested by the sensor calibration experiment. Finally, applications are also discussed.

This paper shows that the method for underground omni-directional vibration signal acquisition is reasonable and feasible. The vibration sensor, designed by this method, of which the triaxial dynamic characteristics are consistent, and the three-dimensional vibration information acquired by this sensor can achieve high-precision localization for an underground explosion point.

The paper describes a new method for omni-directional vibration vector signal acquisition. The vibration sensor is developed based on this method, which has a broad application prospect in the positioning of an underground explosion point, the evaluation of explosive power and other underground projects.

It is generally believed that children’s advertising exposure decreases life satisfaction. This paper aims to investigate whether and how it does by examining the relation between advertising exposure and life satisfaction (Aim 1), as well as the mediating roles of psychological wellbeing (Aim 2) and its underlying dimensions (Aim 3).

Three-wave panel data were collected among 1,133 8-12-year-olds. Psychological wellbeing was measured overall and per dimension (i.e. environmental mastery, personal growth, purpose in life, self-acceptance, autonomy and positive relationships with others).

The authors found a nonsignificant total effect of advertising exposure at Wave 1 on life satisfaction at Wave 3: The negative direct effect was annulled by the positive indirect effect via overall psychological wellbeing at Wave 2. Detailed analysis revealed that personal growth and autonomy functioned as positive mediators, and purpose in life as a negative mediator in the relation between advertising exposure and life satisfaction.

This research informs the ethical debate surrounding child-directed advertising, showing it might stimulate children’s sense of control over their environment, openness to new experiences, direction in life and sense of self-agency.

This study is the first to examine advertising’s effect on life satisfaction and psychological wellbeing simultaneously. The study used a large sample and a longitudinal panel design, allowing conclusions about the specific effects of advertising exposure.

The graduate field of conflict resolution is composed of an eclectic mix of programs, departments, centers, institutes, and think tanks which conduct a wide range of theory development, basic and applied research, service and teaching functions. Prior research on the graduate field has been limited mainly to either direct comparisons between a few graduate programs or summaries of progress made by program clusters, with the largest being a study of 18 programs. The composition and activities of the graduate field as a whole are not well understood, yet are hotly debated. This research attempts to fill part of this knowledge gap by specifically examining all known graduate programs in Peace Studies (PS), Alternative Dispute Resolution (ADR) and Conflict Resolution (CR) in the United States that award verifiable graduate credentials (i.e., certificates, masters, or doctoral degrees) in PS, ADR, or CR. The participants in this study therefore constitute the entire known population (N=94) of graduate credential granting programs in the United States that collectively award roughly 164 certificate and/or degree options. The results of this study constitute a baseline from which to specifically examine and compare program factors including: program location, size, student composition, faculty credentials and areas of expertise. This study also examines program content, including curriculum content, design, and delivery, areas of training specialization; and those elements that participants report make their programs unique. These and other results provide a means of comparing program types and individual program innovations in regard to curriculum, service, research agendas, and areas of practice. The study concludes with participants’ ideas on what program development trends we can expect to see in the coming years as well as where the academy is or is not meeting social needs.

A new hybrid method based on three‐dimensional finite element idealization in the near field and a semi‐analytic scheme using the principles of wave propagation in multilayered half space in the far field is proposed for the dynamic soil‐structure interaction analysis. The distinguishing feature of this technique from direct or indirect boundary integral techniques is that in boundary integral techniques a distribution of sources are considered at the near field boundary. Strengths of these sources are then adjusted to satisfy the continuity conditions across the near‐field/far‐field interface. In the proposed method unknown sources are placed not at the near field boundary but at the location of the structure. Then the Saint‐Venant's principle is utilized to justify that at a distant point the effect of the structure's vibration can be effectively modelled by an equivalent vibrating point force and vibrating moment at the structure's position. Thus the number of unknowns can be greatly reduced here. For soil‐structure interaction analysis by this method one needs to consider only three unknowns (two force components and one in‐plane moment) for a general two‐dimensional problem and six unknowns (three force components and three moment components) for a general three‐dimensional problem. When a vertically propagating elastic wave strikes a structure which is symmetric about two mutually perpendicular vertical planes the structure can only vibrate vertically for dilatational waves and horizontally for shear waves. Under this situation the number of unknowns is reduced to only one whereas in boundary integral and boundary element techniques the number of unknowns is dependent on the number of nodes at the near field boundary, which is generally much greater than six. Several example problems are solved in this paper using this technique for both flexible and rigid structures in multilayered soil media.

The purpose of this paper is to address the problems of interaction of tensile stress-waves with polyurea/fused-silica and fused-silica/polyurea interfaces, and the potential for the accompanying interfacial decohesion.

The problems are investigated using all-atom non-equilibrium molecular-dynamics methods and tools. Before these methods/tools are employed, previously determined material constitutive relations for polyurea and fused-silica are used, within an acoustic-impedance-matching procedure, to predict the outcome of the interactions of stress-waves with the material-interfaces in question. These predictions pertain solely to the stress-wave/interface interaction aspects resulting in the formation of transmitted and reflected stress- or release-waves, but do not contain any information regarding potential interfacial decohesion. Direct molecular-level simulations confirmed some of these predictions, but also provided direct evidence of the nature and the extent of interfacial decohesion. To properly model the initial state of interfacial cohesion and its degradation during stress-wave-loading, reactive forcefield potentials are utilized.

Direct molecular-level simulations of the polyurea/fused-silica interfacial regions prior to loading revealed local changes in the bonding structure, suggesting the formation of an interphase. This interphase was subsequently found to greatly affect the polyurea/fused-silica decohesion strength.

To the authors’ knowledge, the present work is the first public-domain report of the use of the non-equilibrium molecular dynamics and reactive force-field potentials to study the problem of interfacial decohesion caused by the interaction of tensile waves with material interfaces.

Psychological Capital (PsyCap), consisting of hope, efficacy, resilience, and optimism, is a positive state associated with attitudes, behaviors and performance. The purpose of this paper is to investigate a dynamic mediational model posing work engagement as the mediator of the longitudinal relation between PsyCap and job performance.

Data came from all white collar employees who responded to this study’s variables (n=420) from a comprehensive data set drawn from a large communications service company over two consecutive years. Job performance was rated at the end of each year by the direct supervisor as part of the organizational appraisal system.

Structural equation modeling analysis found that both absolute levels and increases in PsyCap predicted subsequent work engagement increases which in turn predicted job performance increases. Moreover, the mediating role of the changes in work engagement between previous PsyCap and performance change was confirmed over time.

There is much to gain in conceptualizing the relations among PsyCap, work engagement and job performance as dynamic, rather than static. The results support the conservation of resources theory, in which employees are motivated to acquire, protect and foster their valued (psychological) resources to attain successful performance outcomes, in order to create a gain cycle of resources (Salanova et al., 2010). Moreover, it provide further empirical validation for the idea that processes, like work engagement, are sustained by personal resources, and that these latter exerts mostly an indirect effect on organizational behavior outcomes (Xanthopoulou et al., 2009b).

These results are important from a practical point of view, because they point to the importance of training interventions aimed at developing and sustaining PsyCap as an important determinant of workers’ motivation and behavior within the organization. Considerable literature offers practical insights and guidelines for developing PsyCap (Luthans et al., 2006, 2015; Luthans and Youssef-Morgan, 2017).

Despite the demonstrated state-like, dynamic nature of PsyCap, its relationship with performance has mainly been statically analyzed and the role of possible mediating mechanisms largely ignored. This study begins to fill this research gap by investigating the dynamic nature of PsyCap in relation to work engagement and job performance and whether over time engagement mediates the relationship between PsyCap and job performance.

Gives introductory remarks about chapter 1 of this group of 31 papers, from ISEF 1999 Proceedings, in the methodologies for field analysis, in the electromagnetic community. Observes that computer package implementation theory contributes to clarification. Discusses the areas covered by some of the papers ‐ such as artificial intelligence using fuzzy logic. Includes applications such as permanent magnets and looks at eddy current problems. States the finite element method is currently the most popular method used for field computation. Closes by pointing out the amalgam of topics.

This paper aims to study the breather, lump-kink and interaction solutions of a (3 + 1)-dimensional generalized shallow water waves (GSWW) equation, which describes water waves propagating in the ocean or is used for simulating weather.

Hirota bilinear form and the direct method are used to construct breather and lump-kink solutions of the GSWW equation. The “rational-cosh-cos-type” test function is applied to obtain three kinds of interaction solutions.

The fusion and fission of the interaction solutions between a lump wave and a 1-kink soliton of the GSWW equation are studied. The dynamics of three kinds of interaction solutions between lump, kink and periodic waves are discussed graphically.

This paper studies the breather, lump-kink and interaction solutions of the GSWW equation by using various approaches and provides some phenomena that have not been studied.