Study on incentive mechanisms of smes crowdsourcing contest innovation.

Lighterness, Paul - Associate SupervisorDealing with insufficient resources is a common challenge yet practical reality for many project managers working within SMEs. With the rise of Web 2.0, crowdsourcing contest innovation (CCI) it is now possible for project managers to use online platforms as a way to collaborate with external agents to fill this resource gap and thus improve innovation. This research uses agent-based modelling to prognosticate the efficacy of crowdsourcing contest innovation with a particular focus on the project manager ‘seeker’ within an SME initiating competitive crowdsourced contest teams made up of individual ‘solver’ participants. The contribution of knowledge will benefit the open innovation community to better understand the main motivational incentives to obtain maximum productivity of a team with limited project management resources. In pursuit of this, the social exchange theory is challenged, this thesis explores the motivation factors that influence solvers to participate in SMEs CCI from the perspectives of benefit perception and cost perception. The results found that non-material factors such as knowledge acquisition and sharing, reputation can stimulate solvers to participate in SMEs CCI more than material (physical money) rewards. Meanwhile, risks such as intellectual property risks and waste of resources are significant participation obstacles. Based on this, the principal- agent theory is used to design the models of team collaboration material incentive mechanism, dynamic reputation incentive mechanism and knowledge sharing incentive mechanism, and the performance of each incentive mechanism is analysed. At last, according to the principles of sample selection, Zbj.com, the China’s most successful crowdsourcing platform of which the main clients are SMEs, is chosen as the research object, and the effectiveness of the incentive mechanisms designed in this thesis is verified. It is found that the material and non-material incentives have been partially applied on the platform, and the explicit, implicit and synergistic effects of incentives are preliminarily achieved. According to the research results, it is suggested that the guarantee measures of the incentive mechanisms should be further developed, such as optimising pricing services and refining task allocation rules.PhD in Water, including Desig

Impact of crowdsourcee’s vertical fairness concern on the crowdsourcing knowledge sharing behavior and its incentive mechanism

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Single-switch high step-up boost converter based on a novel voltage multiplier

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High power high step-up DC/DC converter based on multiple input-terminal voltage multiplier

Voltage multipliers (VMs) are widely used to combine with traditional DC/DC converter to achieve high voltage conversion gain. However, the input-terminals of existing VM circuits are unchangeable to two which make these converters are not suitable for high power/current applications. In this paper, a high power high step-up DC/DC converter based on multiple input-terminal voltage multiplier (MIVM) is presented. Analysis of the operation principles and the performance characteristics of the proposed converter are presented in detail. And an experimental prototype with a rated power of 800W was built to verify the correctness of the theory.</p

A Multi-Input-Port Bidirectional DC/DC Converter for DC Microgrid Energy Storage System Applications

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A Generic Control-Oriented Model Order Reduction Approach for High Step-Up DC/DC Converters Based on Voltage Multiplier

The modeling and control system design of high step-up DC/DC converters based on voltage multipliers (VMs) are difficult, due to the various circuit topologies and the presence of large number of capacitors in VMs. This paper proposes a generic approach to reduce the model order of such converters by replacing the VM capacitors with voltage sources controlled by the output voltage of the converter. Theoretical analysis and simulation results show that the derived models can accurately represent the low frequency response of the converter which is valuable for obtaining a small-signal AC model for control system design. The detailed modeling and controller design process are demonstrated for the converter, and the obtained simulation results are verified experimentally on a 400 W prototype

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High frequency and high power density bipolar DC–DC converter with GaN HEMT

Bipolar DC–DC converter plays an important role in data center and distributed renewable energy unit with the advantages of high efficiency and low cost. In order to improve the power density of bipolar DC–DC converter, a high frequency and high power density bipolar DC–DC converter based on Gallium Nitride High Electron Mobility Transistor (GaN HEMT) is proposed under the development trend of miniaturization, lightweight and high power density of power electronic converter. By using gallium nitride (GaN) switch device, the switching frequency of the converter is increased to 1 MHz, which effectively reduces the volume and weight of the device. In addition, through the design of high frequency driver circuit, two separate pull-up/pull-down outputs are provided for the control signal, and the rising and falling rates of the switch signal are controlled by adjusting the resistance to obtain good performance and driving stability. The experimental results show that the total weight of the converter with radiator is only 121.6 g, the power density is 35.23 W/in3, and the maximum efficiency can reach 92.7%. Compared with the same type of converter, the volume and weight of the converter are greatly reduced, effectively realizing the goals of miniaturization, lightweight and high power density of the converter