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In this paper, a new wide range zero-voltage switching asymmetric half-bridge (AHB) converter with clamping switches for small DC offset current is proposed. Since the hold-up time requirement makes the conventional AHB converter operates asymmetrically in nominal state, a large DC offset current degrades the performance of AHB converters. In order to overcome this problem, the proposed AHB converter operates symmetrically in nominal state and two clamp switches that replace the clamp diodes, operate in hold-up state for additional gain. From the results, it can reduce the DC offset current of transformer and relieves the drawbacks that caused by asymmetric operation. In addition, a large external inductor of the proposed converter makes the wider zero-voltage switching (ZVS) range. Therefore, the proposed converter achieves the high overall efficiency and the smaller DC offset current than the conventional AHB converter. To verify these advantages of the proposed converter, the experiment was implemented with 340∼400V input voltage, 500W (12V/41.67A) output power system at 100 kHz.

Top managers are expected to be rational decision makers. Otherwise, a less than optimal allocation of limited resources results in a loss of competitiveness. Previous studies in accounting, management, and psychology provide evidences on the management's escalation of commitment to an alternative with negative feedback, which may cause suboptimal performances. The purpose of this study is to examine the escalation of commitment by managers. Firstly, it is examined whether managers exhibits such behavior. Secondly, the extent to which variables of individual responsibility, information asymmetry, and risk preference affect the level of commitment is examined. To achieve research purposes, a laboratory experiment is conducted. Analyses of data indicate that escalation of commitment persist in the face of the negative feedback. The higher the level of individual responsibility, subjects committed more resources to an investment project with a negative feedback. Information asymmetry significantly contributed to the level of commitment. Risk preference, however, was found to have little effects on the escalation of commitment. The results suggest that managers are exposed to the risk of escalating commitment to the suboptimal decisions. This study extended previous research by allowing subjects to make investment decisions for their own, and by clearly communicating negative feedback. Development of accounting information systems is needed to help management reduce escalation of commitment in the face of negative feedback.