Link failure protection and restoration in WDM optical networks

In a wavelength-division-multiplexing (WDM) optical network, the failure of fiber links may cause the failure of multiple optical channels, thereby leading to large data loss. Therefore the survivable WDM optical networks where the affected traffic under link failure can be restored, have been a matter of much concern. On the other hand, network operators want options that are more than just survivable, but more flexible and more efficient in the use of capacity. In this thesis, we propose our cost-effective approaches to survive link failures in WDM optical networks. Dynamic establishment of restorable connections in WDM networks is an important problem that has received much study. Existing algorithms use either path-based method or link-based method to protect a dynamic connection; the former suffers slow restoration speed while the latter requires complicated online backup path computation. We propose a new dynamic restorable connection establishment algorithm using p-cycle protection. For a given connection request, our algorithm first computes a working path and then computes a set of p-cycles to protect the links on the working path so that the connection can survive any single link failure. The key advantage of the proposed algorithm over the link-based method is that it enables faster failure restoration while requires much simpler online computation for connection establishment. Tree-based schemes offer several advantages such as scalability, failure impact restriction and distributed processing. We present a new tree-based link protection scheme to improve the hierarchical protection tree (p-tree) scheme [31] for single link failure in mesh networks, which achieves 100% restorability in an arbitrary 2-connected network. To minimize the total spare capacity for single link failure protection, an integer linear programming (ILP) formulation is provided. We also develop a fast double-link failure restoration scheme by message signaling to take advantage of the scalable and distributed processing capability of tree structure

Tenders with Different Risk Preferences in Construction Industry

Underlying the fact that different tenderers have different preferences on risk-taking, this study investigates the different tenderers' behaviors in one-shot construction bid auctions. Our model extends the preconditions of previous assumption that all tenderers are characterized by neutral risk-taking in the original tendering model for lowest-price sealed tender. A general tendering model for the lowest-price sealed tender is established to explain the behavior of tenderers during the tendering. The results indicate that construction estimate is affected by the degree of uncertainties in the construction industry. Therefore, in a lowest-price sealed tender, risk-averse tenders would tender a higher price and conversely risk-seeking tenderers would tender a lower price when risk-neutral tenderers would tender a middle price. However, the risk-seeking tenderers are more likely to win the bid.Auction, tender, uncertainty, preference, construction industry

Link failure protection and restoration in WDM optical networks

In a wavelength-division-multiplexing (WDM) optical network, the failure of fiber links may cause the failure of multiple optical channels, thereby leading to large data loss. Therefore the survivable WDM optical networks where the affected traffic under link failure can be restored, have been a matter of much concern. On the other hand, network operators want options that are more than just survivable, but more flexible and more efficient in the use of capacity. In this thesis, we propose our cost-effective approaches to survive link failures in WDM optical networks. Dynamic establishment of restorable connections in WDM networks is an important problem that has received much study. Existing algorithms use either path-based method or link-based method to protect a dynamic connection; the former suffers slow restoration speed while the latter requires complicated online backup path computation. We propose a new dynamic restorable connection establishment algorithm using p-cycle protection. For a given connection request, our algorithm first computes a working path and then computes a set of p-cycles to protect the links on the working path so that the connection can survive any single link failure. The key advantage of the proposed algorithm over the link-based method is that it enables faster failure restoration while requires much simpler online computation for connection establishment. Tree-based schemes offer several advantages such as scalability, failure impact restriction and distributed processing. We present a new tree-based link protection scheme to improve the hierarchical protection tree (p-tree) scheme [31] for single link failure in mesh networks, which achieves 100% restorability in an arbitrary 2-connected network. To minimize the total spare capacity for single link failure protection, an integer linear programming (ILP) formulation is provided. We also develop a fast double-link failure restoration scheme by message signaling to take advantage of the scalable and distributed processing capability of tree structure.</p

Leveraging interdependencies among platform and complementors in innovation ecosystem.

In the platform-based innovation ecosystem, the symbiotic evolution and interaction between the participating entities have drawn extensive attention. However, there is a lack of understanding of the co-specialization and co-innovation among members of the innovation ecosystem. This paper addresses this gap. In this paper, the collaborative innovation between a platform firm and different kinds of complementors, and its effects on the performance of the innovation ecosystem are simulated through an improved NK model. The result shows that the co-innovation performance between generalist complementors and the platform firm is generally outperformed than that between the specialist complementors and the platform firm. As the interdependencies between the complementary components get stronger, the innovation performance of the innovation ecosystem influenced by the interaction between different types of complementors and platform firms tend to be an inverted U-shape

The Path Constitution of Platform Evolution: An Organizational Momentum View

Although the evolutionary pathways are critical to the success of platforms, extant literature has provided little insight into the dynamic processes of the platform evolution, let alone how platforms constitute the evolutionary pathways over time. Against this backdrop, this study examines the evolutionary path constitution of platforms by adopting an organizational momentum lens. Through an exploratory case study of Pinduoduo, it provides evidence of path dependence under the network effects and of path creation resulting from the deliberate actions conducted by the platform firms. Moreover, this study identifies three platform strategies to manage its momentum to facilitate platform evolution and sustainability. Furthermore, this study develops a holistic framework to explain the interactions between platform momentum and path constitution by considering the outcomes of these strategies. The findings and developed framework shed novel light on the path constitution of platform evolution and provide new insight into the sustainability of the platform firms and platform-based markets by leveraging momentum thinking

The Path Constitution of Platform Evolution: An Organizational Momentum View

Although the evolutionary pathways are critical to the success of platforms, extant literature has provided little insight into the dynamic processes of the platform evolution, let alone how platforms constitute the evolutionary pathways over time. Against this backdrop, this study examines the evolutionary path constitution of platforms by adopting an organizational momentum lens. Through an exploratory case study of Pinduoduo, it provides evidence of path dependence under the network effects and of path creation resulting from the deliberate actions conducted by the platform firms. Moreover, this study identifies three platform strategies to manage its momentum to facilitate platform evolution and sustainability. Furthermore, this study develops a holistic framework to explain the interactions between platform momentum and path constitution by considering the outcomes of these strategies. The findings and developed framework shed novel light on the path constitution of platform evolution and provide new insight into the sustainability of the platform firms and platform-based markets by leveraging momentum thinking

The Effect of Carbon Price Volatility on Firm Green Transitions: Evidence from Chinese Manufacturing Listed Firms

Accelerating the promotion of the green transition can help to achieve high-quality development in manufacturing industries. In terms of policies that encourage the transition to green production, carbon trading is a direct and effective means of achieving this goal, and the carbon price is an important regulator in trading. Normally, firms respond to carbon prices by making three behavioral choices: production restrictions, pollution reduction, and the technological transition to green production. This study examines the effect of carbon price volatility on the decision to conduct green production, i.e., transforming to sustainable technologies and processes. In addition, this paper also investigates whether organizational resource slack and organizational technical standards moderate the relationship between the carbon price volatility and firms’ green transitions. The results suggest that a steadily increasing carbon price will motivate firms to make a green transition, but if the carbon price is volatile, firms will be reluctant to make a green transition. This tendency to make a green transition is stronger when firms have resource slack and have implemented green technical standards. The findings provide empirical evidence and policy implications regarding how manufacturing firms can accelerate their green transition

Social Capital and Sustainable Innovation in Small Businesses: Investigating the Role of Absorptive Capacity, Marketing Capability and Organizational Learning

Facing resource constraints and fierce competition, it is relatively difficult for small firms to achieve product innovation to gain sustainable development independently. Previous studies have explored the positive relationship between social capital and product innovation, yet there is still a lack of a comprehensive understanding of the underlying mechanism and the boundary conditions. Drawing upon the dynamic capabilities framework, we expect that absorptive capacity and marketing capability will mediate the relationship between social capital and new product development. Moreover, since product innovation is considered a process of learning, we also examine the moderating effects of explorative learning, and exploitative learning within moderated mediation models. Employing a sample of 221 small firms based in China, we find that social capital is indeed positively associated with new product development and is simultaneously fully mediated by absorptive capacity and marketing capability. Furthermore, the impact of absorptive capacity on new product development is amplified when a condition of explorative learning exists. This study, therefore, advances the current understanding on the predictors of innovation and enriches the dynamic capabilities theory, and also provides empirical support for the sustainable development of small firms