Risky Group Decision Making: A Comparative Analysis of FTF and CMC Teams in Stock-Trak Investment Simulations

Few studies have explicitly focused on risky group decision making in information sharing or examined the manifestation of communication differences in face-to-face (FTF) and computer-mediated communication (CMC) teams. Hypothesizing that information-sharing behaviors could be influenced not only by contextual forces but also by personality and trust, we integrate communication mode, trust and personality into a theoretical framework, and also examine the possible impact of these constructs on risky group decision-making outcomes. Our interdisciplinary study integrates the fields of information system management, investment analysis and financial education by examining both FTF and CMC teamwork in a Stock-Trak portfolio simulation. We find that contrary to the common wisdom, even though FTF team members tend to feel greater levels of trust, affiliation and satisfaction in their team collaboration process, CMC teams eventually outperform their FTF counterparts by having greater portfolio returns and investor utilities

Power conversion and signal transmission integration method based on dual modulation of DC-DC converters

For the development of communication systems such as Internet of Things, integrating communication with power supplies is an attractive solution to reduce supply cost. This paper presents a novel method of power/signal dual modulation (PSDM), by which signal transmission is integrated with power conversion. This method takes advantage of the intrinsic ripple initiated in switch mode power supplies as signal carriers, by which cost-effective communications can be realized. The principles of PSDM are discussed, and two basic dual modulation methods (specifically PWM/FSK and PWM/PSK) are concluded. The key points of designing a PWM/FSK system, including topology selection, carrier shape, and carrier frequency, are discussed to provide theoretical guidelines. A practical signal modulation-demodulation method is given, and a prototype system provides experimental results to verify the effectiveness of the proposed solution

Wireless power and data transfer via a common inductive link using frequency division multiplexing

For wireless power transfer (WPT) systems, communication between the primary side and the pickup side is a challenge because of the large air gap and magnetic interferences. A novel method, which integrates bidirectional data communication into a high-power WPT system, is proposed in this paper. The power and data transfer share the same inductive link between coreless coils. Power/data frequency division multiplexing technique is applied, and the power and data are transmitted by employing different frequency carriers and controlled independently. The circuit model of the multiband system is provided to analyze the transmission gain of the communication channel, as well as the power delivery performance. The crosstalk interference between two carriers is discussed. In addition, the signal-to-noise ratios of the channels are also estimated, which gives a guideline for the design of mod/demod circuits. Finally, a 500-W WPT prototype has been built to demonstrate the effectiveness of the proposed WPT system