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The purpose of this study is to develop the existence and mechanism of stress corrosion cracking (SCC) for A517 steel in marine environments.

Slow strain rate test (SSRT) and constant load tests were used to investigate the SCC susceptibility of A517 steel. In addition, the additive stresses caused by the corrosion film and hydrogen entering into steel were applied to reveal the fundamental mechanism of the SCC.

The SCC susceptibility increased due to anodic dissolution and additive stress caused by the corrosion-produced film under anode polarization. Furthermore, the SCC susceptibility increased with increasing cathodic polarization, which is due to the increased additional stress caused by hydrogen entering into the steel. However, when the cathode polarization further increased, the additional stress remained due to the constant hydrogen content, thus the SCC susceptibility did not vary. Moreover, the SCC susceptibility of A517 steel under an alternate immersion environment (AIE) was lower than that under a full immersion environment and the steel under the AIE with 0.5 W/D had the lowest SCC susceptibility.

The stress corrosion behaviors of A517 in marine environments under various conditions were systematically analyzed.

The purpose of this study is to elucidate the effect of Mn addition on the corrosion behavior of stainless steel.

Chronoamperometry, quasi-steady-state polarization and electrochemical impedance spectroscopy were used to investigate the corrosion behavior of Mn added A13Cr-HS sample and original S13Cr samples. In addition, the corrosion product film was characterized by a field emission scanning electron microscope equipped with energy-dispersive spectroscopy and X-ray photoelectron spectroscopy.

The A13Cr-HS sample with 8 wt.% Mn addition maintained good general corrosion resistance in both acidic and alkaline solutions compared to the original S13Cr sample. Additionally, the A13Cr-HS sample had good pitting resistance in an alkaline solution containing Cl⁻, but a weaker resistance in an acidic solution.

The influence of Mn addition on the formation mechanism of the passive film was systematically analyzed.

The purpose of this study is to develop a model extending Oriani’s formula by introducing a normalised concentration to simulate hydrogen diffusion in a multi-material system such as coated steels, under the presence of traps.

Implemented through the finite element method based on the analogy between mass diffusion and heat transfer, the governing equation was applied to investigate the combined effects of hydrogen traps and surface oxide films on hydrogen permeation in ferritic steels.

This study shows that the effective diffusivity varies over several orders of magnitude depending on the traps and films. This explains the divergence of measured hydrogen diffusivities in steels. It is revealed that hydrogen permeation in steels with Pd or Ni film is a trapping-dominant transport process, while hydrogen permeation in steel with oxide film is a process controlled by both trapping effect and retarding effect of oxide film. The oxide film enhances total hydrogen concentration within the steel substrate and is therefore detrimental. The Pd or Ni film has a little influence on total hydrogen concentration distribution depending on trapping energy.

Hydrogen flux curves and transient hydrogen concentration distributions can be directly obtained through the developed model. The proposed approach can also be extended to investigate other interstitial (i.e. carbon, oxygen and nitrogen) diffusion with traps revisited in complex systems.

Cobalt-based alloys exhibit a unique combination of wear resistance, strength and corrosion resistance. Localized corrosion of such alloys in seawater system can be several orders of magnitude faster than general corrosion, and direct experimental evidence of the local activation process is still lacking, which makes the accurate prediction for properties difficult, especially for long-term corrosion. The purpose of this study is revealing the relationship between multiple environments and corrosion properties to predict the corrosion of cobalt-based alloys.

A data-driven method for the prediction of the corrosion behavior of cast and hot isostatic-pressed CoCrMo/W alloys in seawater is proposed. The gradient boosting regression models calculate mean relative errors (MREs) of 0.160 and 0.435 by evaluating a hold-out set for breakdown potential (E_b) and maximum current density (i_max), respectively, considering various compositions, synthesis methods and corrosion environments.

The models can be used to estimate the “unseen” cobalt-based alloy after immersion in 3.5 Wt.% NaCl solution for one, two, four and eight months to obtain high precision with MREs of 7.8% and 9.8% for E_b and i_max, respectively.

Machine learning method provides novel and promising insights for the prediction of localized corrosion properties.

The purpose of this paper is to study the pricing efficiency of convertible bonds and arbitrage opportunities between the convertible bonds and the underlying stocks thus improve market efficiency.

Using nonparametric fixed effect panel data model, the authors build pricing model of convertible bonds and obtain fitted value for them. Then the authors constructs simultaneous confidence band for the smooth function to identify mispricing and study the pricing efficiency and arbitrage opportunities of convertible bonds.

Result shows, convertible bonds’ prices largely depend on stock prices. Pricing efficiency does not improve during the past few years as there are quite a few trading opportunities. Arbitrage opportunities increase as the stock prices approach it maxima, and selling opportunities for convertible bonds surpass buying opportunities which indicates that investors use market neutral strategies to arbitrage. Pricing efficiencies varies a lot and it is affected by the features of the stocks and convertible bonds. Index stocks eligible for margin trading with high liquidity enjoy higher pricing efficiency.

The study does not take into account trading cost and risk management measures.

Arbitrage between the underlying and the convertible bonds is profitable and contributes to pricing efficiency therefore should be encouraged. The regulator should pay attention to the extreme mispricing of the underlying and convertible bonds which cannot be corrected by the market as there might be manipulation.

Since traditional pricing methods are based on the framework of non-arbitrage equilibrium with the assumption of balanced and perfect market, there are many restrictions in the pricing process and the practical utility is somewhat limited, and the impractical assumptions lead to model risk. This study uses nonparametric regression to study the pricing of convertible bonds thus circumvents the problem of model risk. Simultaneous confidence band for smooth function identifies mispricing and explicitly reflects the variation of pricing efficiency as well as signalizes trading opportunities. Application of nonparametric regression and simultaneous confidence band in derivative pricing is advantageous in accuracy and simplicity.

The aim of this research was to identify and describe driving forces of importance in sponsorship during the seven years preceding a mega-sporting event like the Olympic Games 2008 in Beijing. This was done through the development of a conceptual 'meansobjectives model' linking sponsorship to brand equity factors and to objectives. The proposed model enables matching with real data consisting of 200 randomly chosen advertisements, articles and press releases from Chinese newspapers and the internet, revealing six types of means-objectives in sponsorship.

The purpose of this paper is to identify and describe the key driving forces in international sponsorship during the years preceding the 2008 Olympic Games in Beijing.

A “means‐objectives model” is applied, thereby linking sponsorship to brand equity factors and to strategic aims. Co‐branding, revenue streams and new customers are identified as means factors. The objective factors are presented in three dimensions: product, corporation and region. The analysis is based on 492 advertisements, articles and press releases collected from Chinese newspapers and Chinese official web pages covering the period 2001‐2007.

Analysis sees seven dominant means‐objectives combinations in sponsorship leading to different pattern of sponsor advertising strategies depending on the lead time to the Olympic Games. First, sponsors mainly focus on co‐branding marketing efforts. In the second stage, global Olympic sponsors link co‐branding with corporation image, Chinese brands are focusing on product/corporation image and new customers. In the third stage global Olympic sponsors focus more on local markets and customers in advertising. Chinese brands tend to keep an activation strategy based on revenue and product. Only a few local sponsors place emphasis on leveraging their sponsorship investment toward creating an international image.

Data collection is limited to a period of altogether three months in 2006 and 2007, focusing on Chinese print media available in Beijing and Shanghai universities' libraries. Given the size of the Chinese media market the data therefore consist only of a random selection of advertisements. Further, the sample does not cover different marketing channels, like TV, radio etc., which might also be part of the sponsor's advertising strategy.

In addition to providing further understanding of Olympic sponsor advertising behavior and sponsorship in an emerging market context, this paper provides insights into how the strategic aims related to sponsorship depended on the level of internationalization of the firm.

The purpose of this paper is to describe and explain the advertising behavior seen as an activation strategy performed by Olympic sponsors in an emerging market context. It provides insights into the strategic goals related to sponsorship.

The longitudinal approach taken opens the possibility to explore the dynamics of the strategies of Chinese as well as foreign firms in China. Theories on how sponsorship works cannot assist in explaining outcomes of sponsor-linked marketing, and since the actors involved rarely divulge their genuine intentions or their reciprocal contractual arrangements with the sponsored property, a new methodology has to be developed. A means-objective framework of sponsoring consists of six factors, which were applied to analyze 739 advertisements, articles and press releases collected from Chinese newspapers and Chinese official web pages covering a period of eight years (2001-2008) prior to the Olympic Games in Beijing. Based on a qualitative content analysis and nine means-objectives combinations in sponsorship patterns the authors discovered four dominant advertising strategies.

Lead-time is a key concept when analyzing sponsor advertising strategies. The authors conclude from the longitudinal data that the time gap between signing the contract and the dates of the event influences the strategy of the sponsoring corporations. The authors also observe that the advertising content changes over time and the sponsors craft different “advertising strategies” in different periods. Within this context the authors categorized two different advertising strategies. The sponsors are assumed to conduct a “Short Advertising Strategy” different from the “Long Advertising Strategy.” Both are examples of activation strategies.

Advertising strategies and activation seems to be dependent on the lead-time to the Olympic Games and the level of internationalization of the sponsoring firm.

The paper aims to find the correlation between the microparameters and the macroparameters of the soil. The study aims to calibrate the macroscale and microscale parameters of rolling resistance contact models to successfully apply the discrete element method to do some research of the geotechnical problem.

The paper opted for an exploratory study using the PFC3D to simulate the triaxial tests that include more than 50 cases and the coupling analysis method, which considering several effect of various factors.

The paper provides a quantitative relationship between the macroparameters and microparameters of the rolling resistance linear model and a method for fast calibration of macroscopic parameters is proposed and verified by a triaxial test example.

This paper provides the quantitative relationship of micro and macroparameters in the rolling resistance linear model by studying a single factor and considering the coupling effect of various factors and a fast method for the calibration of microparameters based on the rolling resistance linear model is proposed.