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The purpose of this paper is to determine both analytically and numerically the solution to a new one-dimensional equation for the propagation of small-amplitude waves in shallow waters that accounts for linear and nonlinear drift, diffusive attenuation, viscosity and dispersion, its dependence on the initial conditions, and its linear stability.

An implicit, finite difference method valid for both parabolic and second-order hyperbolic equations has been used to solve the equation in a truncated domain for five different initial conditions, a nil initial first-order time derivative and relaxation times linearly proportional to the viscosity coefficient.

A fast transition that depends on the coefficient of the linear drift, the diffusive attenuation and the power of the nonlinear drift are found for initial conditions corresponding to the exact solution of the generalized regularized long-wave equation. For initial Gaussian, rectangular and triangular conditions, the wave’s amplitude and speed increase as both the amplitude and the width of these conditions increase and decrease, respectively; wide initial conditions evolve into a narrow leading traveling wave of the pulse type and a train of slower oscillatory secondary ones. For the same initial mass and amplitude, rectangular initial conditions result in larger amplitude and velocity waves of the pulse type than Gaussian and triangular ones. The wave’s kinetic, potential and stretching energies undergo large changes in an initial layer whose thickness is on the order of the diffusive attenuation coefficient.

A new, one-dimensional equation for the propagation of small-amplitude waves in shallow waters is proposed and studied analytically and numerically. The equation may also be used to study the displacement of porous media subject to seismic effects, the dispersion of sound in tunnels, the attenuation of sound because of viscosity and/or heat and mass diffusion, the dynamics of second-order, viscoelastic fluids, etc., by appropriate choices of the parameters that appear in it.

Consumer expectation not only influences purchase decision but also post-purchase satisfaction and word-of-mouth (WOM). This study aims to develop theories of initial expectation management by suggesting when it is desirable for new products to raise or lower consumer expectations. It systematically examines the interplay of product value and consumer heterogeneity in the dynamic process of new product diffusion under competition.

Drawing on traditional diffusion and choice models, this study develops an agent-based model to formalize and analyze how consumers’ initial expectations of a new product influence the interdependent processes of product sales, consumer satisfaction and WOM. The simulation analyses in controlled settings help understand the underlying mechanisms in a stepwise manner.

The results show that, although the optimal strategy for low-value products is to induce consumer expectations higher than product value, high-value products are better introduced with expectations formed close to it. The results also highlight an important drawback of “under-promising” strategies in reducing the base and volume of WOM. Further, the analysis illustrates how consumer heterogeneities in product valuation and initial expectation affect the effectiveness of expectation management. For high-value products, both heterogeneities reduce the effectiveness of the optimal strategy. For low-value products, however, value heterogeneity enhances the effectiveness, whereas expectation heterogeneity reduces it.

Firms introducing new products should be sensitive to how consumers value the product and form expectations about it. Different from firms that must rely on aggressive advertising to sell inferior products by building up high expectations, those with superior products can rely more on the power of consumer WOM, which is much less costly and thus gives them a competitive advantage. Firms should also pay attention to how diversified the consumers are in product valuation and expectation. The expectation management strategy is more effective when consumers form more similar expectations. Inferior firms may leverage this mechanism to neutralize their disadvantages.

The articulated mechanisms help push forward the research on new product diffusion and consumer expectation management. To the best of the authors’ knowledge, this is one of the first studies to systematically analyze the impact of consumer heterogeneity on the effectiveness of expectation management.

This article proposes an evaluation of capital investments that accounts for not only the initial assets, but also any potential growth options.

Using a piecewise linear approximation, a robust valuation technique is demonstrated for analyzing capital investment opportunities containing expansion options in a finite time horizon.

This process not only recognizes the option‐like characteristics of the initial investment opportunity, but also recognizes the option‐creating characteristics of the investment. This analysis shows that the value of capacity expansion options created by the initial investment has different dynamic characteristics from the assets in place. Although the growth options do not appear in the early investment premium, its impact on the investment decision is embedded in the investment threshold. When the time to expiration is short and the cost to delaying the assets in place is low, this analysis suggests that the initial investment decision might be made by ignoring the growth options.

This real option methodology provides a continuous solution to the optimal investment threshold and is a viable alternative to the traditional finite difference approach.

The dual-phase-lag (DPL) model and Lord-Shulman theory with one relaxation time are applied to study the effect of the gravity field, the magnetic field, and the hydrostatic initial stress on the wave propagation in a two-temperature generalized thermoelastic problem for a medium with an internal heat source that is moving with a constant speed. The paper aims to discuss this issue.

The exact expressions of the considered variables are obtained by using normal mode analysis.

Numerical results for the field quantities are given in the physical domain and illustrated graphically in the absence and presence of the gravity field as well as the magnetic field. Comparisons are made between the results of the two different models with and without temperature dependent properties and for two different values of the hydrostatic initial stress. A comparison is also made between the results of the two different models for two different values of the time.

In the present work, the author shall formulate a two-temperature generalized magneto-thermoelastic problem for a medium with temperature dependent properties and with an internal heat source that is moving with a constant speed under the influence of a gravity field and a hydrostatic initial stress. Normal mode analysis is used to obtain the exact expressions for the displacement components, thermodynamic temperature, conductive temperature, and stress components. A comparison is carried out between the considered variables as calculated from the generalized thermoelasticity based on the DPL model and the L-S theory in the absence and presence of a magnetic field as well as a gravity field. Comparisons are also made between the results of the two theories with and without temperature dependent properties and for two different values of hydrostatic initial stress. A comparison is also made between the results of the two different models for two different values of the time.

On May 17, 2012, the social networking company Facebook Inc. fixes its initial public offering (IPO) price at $38.00 a share. Over the next couple of months, contrary to expectations raised by previous IPOs, the stock price crashes more than 50 per cent. Immediately, the question arises whether the issuer’s or the stock market’s pricing of the share are in line with the firm’s fundamentals. Thus, the purpose of this paper is to determine the company value in close proximity to the date of IPO.

As Facebook is an archetypal internet growth company, it is evaluated using the Schwartz/Moon model. This approach features significant advantages over traditional valuation models and more adequately captures the characteristics of growth companies.

As of September 30, 2012, the fundamental share value determined was $26.53, which exceeded the market price per share of $22.66 by 22.48 per cent, but was far less than the IPO stock price. The subsequent sensitivity analysis reveals the robustness of the result to key input parameters.

The results raise doubts about the IPO price of Facebook. Furthermore, this paper is of value from a more conceptual perspective in that an extended version of the Schwartz/Moon model is provided. Beyond extensions previously discussed in the subject-based literature, the authors include stochastic interest rates (as an additional source of uncertainty) and investigate their valuation effects.

The purpose is to predict the distribution of the residual pretightening force of the bolt group under the action of any initial pretightening force, and to achieve the final residual pretightening force as the target to solve the initial pretightening force value to be applied.

Based on the finite element method and the elastic interaction theory between bolt group, this paper establishes a prediction model for the residual pretightening force distribution of bolt group for one-step pretightening and multi-step pretightening of gasketless flange connection systems. In addition, using the general modeling method given in this paper, the prediction model of residual pretightening force of long plate bolt connection system is established, and compared with reference, which fully proves the effectiveness and universality of the general prediction model of residual pretightening force of bolt group.

The appropriate pretightening sequence, increasing the number of pretightening steps and variable amplitude loading can effectively reduce the influence of elastic interaction and improve the uniformity of residual pretightening force of the bolt group. And the selection of material, number of bolts and connected thickness of bolt connection system also has a great influence on the distribution of residual pretightening force of bolt groups.

The general prediction model for the residual pretightening force of bolt group of connecting structural components considering elastic interaction given in this paper can provide a reference for the design and optimization of the bolt assembly process of the rotor system and the casing system in aero-engine and the prediction of the performance of the connecting system.

This study aims to predict the volume changes and collapse potential (CP) associated with the changes in soil suction by using the pressure cell and the effect of initial load on soil suction. Three types of gypseous soils have been experimented in this study, sandy gypseous soil from different parts of Iraq. A series of collapse tests were carried out using the oedometer device [single oedometer test (SOT) and double oedometer test (DOT)]. In addition, large-scale model with soil dimensions 700 × 700 × 600 mm was used to show the effect of water content changes in different relations (collapse with time, stress with time, suction with time, etc.).

A series of collapse tests were carried out using the oedometer device (SOT and DOT). In addition, a large-scale model with soil dimensions 700 × 700 × 600 mm was used to show the effect of water content changes in different relations (collapse with time, stress with time, suction with time, etc.).

The CP increases with the increasing of the void ratio for each soil. For each soil, the CP decreased when the initial degree of saturation increased. Kerbala soil with gypsum content (30%) revealed collapse value higher than Tikrit soil with gypsum content (55%) under the same initial conditions of water content and density, this is because the higher the Cu value of Kerbala soil is, the more well-graded the soil will be. Upon wetting, the smaller particles or fractions of the well-graded soil tend to fill in the existing voids, resulting in a lower void ratio as compared to the poorly graded one. Consequently, soils with high Cu value tend to collapse more than poorly graded ones. The compressibility of the soil is low when loaded under unsaturated condition, the CP for samples tested in the DOTs under stress level 800 kPa are greater than those obtained from collapse test at a stress level of 200 kPa.

The initial value of suction for all soils increases with initial water content decreases.

The purpose of this paper is to report the results of a study concerning how fundamental-motivated investors, and their subsequent impact on the path of prices, affect the severity of price bubbles in an experimental laboratory asset market.

In a laboratory experiment, asset markets are manipulated by systematically replacing inexperienced human traders with automated traders programmed to submit bids and asks at fundamental value.

When traders in a market are automated to invest on fundamentals, deviations from fundamental value are initially suppressed, but reappear when automated traders cease to influence prices. A significant reduction in the severity of the resulting bubble may be attributed to the interaction of automated traders and humans through the initial path of prices when controlling for changes in liquidity. This reduction corresponds to reduced autocorrelation in the time series of returns.

This paper represents the first attempt (to the authors’ knowledge) to extend the intervention approach of the seminal paper by Smith et al. (1988) to systematically study the extent to which manipulation of initial path of prices impacts the formation and magnitude of bubbles in the laboratory.

Briefing in a project delivery context is one of the most critical factors in the project success. It defines client requirements, translates these needs into design criteria and generates a design concept. A lack of briefing clarity is one of the main causes of design changes and may lead to project cost and time overruns. This research aims to assess the brief clarity and its influence on project cost and duration.

This research created the PDRI-SD technique by utilising a system dynamic (SD) approach and project definition rating index (PDRI) tool to model the complex system of project briefing and associated variables. Stock and flow diagrams of the main subsystems including the briefing, the detailed design and the construction process, were developed to assess the influence of brief clarity on project cost and time. The PDRI was adopted to measure the briefing clarity and apply in the model. PDRI-SD was then tested in Australian building refurbishment projects to assess the model's effectiveness.

The simulation results indicated that a minor reduction of the lack of clarity throughout the initial briefing process could significantly mitigate unpredicted delay and cost overruns during the detailed design and the construction stage.

This research contributed to the existing body of knowledge by developing an effective technique to measure the impact of lack of brief clarity on project cost and time performance. PDRI-SD can also aid project clients to predict the influence of the initial defined brief on the detailed design and construction process using the historical data of similar previous projects. It provides clients with feedback, indicating whether the brief meets project requirements or whether parts of the project brief require more clarification/rectification before the project handover to the builders.