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This paper proposed a novel high step-up converter with double boost paths. The circuit uses two switches and one double-path voltage multiplier cell to own the double boost and interleaved effects simultaneously. The voltage gain ratio of the proposed DC-DC converter can be three times the ratio of the conventional boost converter such that the voltage stress of the switch can be lower. The high step-up performance is in accordance with only one double-path voltage multiplier cell. Therefore, the number of diodes and capacitors in the proposed converter can be reduced. Furthermore, the interleaved property of the proposed circuit can reduce the losses in the rectifier diode and capacitor. The prototype circuit with 24-V input voltage, 250-V output voltage, and 150-W output power is experimentally realized to verify the validity and effectiveness of the proposed converter. Figure 4. Operational modes of the proposed converter: (a) stage 1; (b) stage 2; (c) stage 3; and (d) stage 4.Figure 5. Operational waveforms of the proposed converter: (a) waveforms of the voltages across the switches and rectifiers; (b) waveforms of the currents; and (c) waveforms of the voltages across the inductors.

The binary oxide based resistive memories showing superior electrical performances on the resistive switching are reviewed in this paper. The status and challenges of the HfO X based resistive device with excellent memory properties are presented. Several future challenges for the filamentary type switching device are also addressed.

In this paper, we base our research by dealing with a real-world problem in an enterprise. A RFM (recency, frequency, and monetary) model and K-means clustering algorithm are utilized to conduct customer segmentation and value analysis by using online sales data. Customers are classified into four groups based on their purchase behaviors. On this basis, different CRM (customer relationship management) strategies are brought forward to gain a high level of customer satisfaction. The effectiveness of our method proposed in this paper is supported by improvement results of some key performance indices such as the growth of active customers, total purchase volume, and the total consumption amount.

A filtering power divider (PD) with good isolation performance is presented. The isolation performance is improved by introducing a distributed isolation network (DINW) to replace the conventional resistor isolation network. Moreover, the proposed DINW can be incorporated into a filter design to form a filtering PD. The filtering power divider was implemented at a centre frequency of 1 GHz with a fractional bandwidth of 56%, and the measured isolation is better than 23 dB across the entire operating band.Introduction: Power dividers (PDs) are frequently used for splitting/ combining power in various microwave and millimetre-wave systems. The conventional Wilkinson divider provides poor band selectivity and passes signal outside the operating frequencies. Efforts made to improve the passband selectivity of PDs are found in recent studies [1][2][3][4]. Coupled lines [1] and an interdigital coupling structure [2] were adopted to implement compact PDs with a bandpass response. Fourth-order filters are incorporated in the transmission paths of PDs to achieve satisfactory passband selectively [3,4]. Although these studies demonstrated satisfactory power division and filtering properties, their isolation bandwidths are still narrow. To extend the isolation bandwidth, an 'RLCT' isolation network was proposed to realise a PD with extended isolation bandwidth [5]. However, several lumped elements are required in the 'RLCT' isolation network and that increases the complexity of the circuit fabrication.In this Letter, a novel filtering PD with good isolation performance is proposed. A distributed isolation network (DINW) is used to replace the conventional resistor isolation network (RINW) of a conventional Wilkinson PD as shown in Fig. 1. The loading stubs in the DINW can minimise the difference between the even-and odd-mode input impedances to improve the isolation performance. Besides, the DINW can be absorbed into a bandpass filter design to form a filtering PD.