A quality status encoding scheme for PCB-based products in IoT-enabled remanufacturing

In this paper,a binary-extensible quality status encoding scheme,named IQSCT(IoT quality status code table),is proposed for the PCB-based product with available recovery options in remanufacturing.IQSCT is achieved by code evolution based on binary logic,in which the product flow and the quality information flow are integrated,and three key features of PCB-based product(PCB-module association,assembly-disassembly logic,and disassembly risk)are involved in production costing.With IQSCT,the manufacturer can have better decisions to reduce remanufacturing cost and improve resource utilization,which is verified by a case study based on the real data from BOM cost and corresponding estimation of Apple iPhone 11 series.

Colored object encoding scheme in ghost imaging system using orbital angular momentum

A colored object encoding scheme in a ghost imaging （GI） system using orbital angular momentum is in- vestigated. A colored object is decomposed into three components and then each component is obtained in the idler arm using a multiple grayscale encoding scheme. Afterward, we synthesize the three reconstructed components into a colored image. The scheme is conducted and then presented through numerical simula- tions and experiments. The simulation result shows that the average peak signal-to-noise ratio （PSNR） is at 21.636 for the reconstructed color of the ＂Lena＂ image with 255 gray scales. The experiment also shows that the PSNR is 8.082 for the reconstructed color of the ＂NUPT＂ characters. The successful imaging of colored obiects extends the further use of the GI technique

Path-partitioned encoding supports wildcard-awareness twig queries

Finding all occurrences of a twig query in an XML database is a core operation for efficient evaluation of XML queries. It is important to effiectively handle twig queries with wildcards. In this paper, a novel path-partitioned encoding scheme is proposed for XML documents to capture paths of all elements, and a twig query is modeled as an XPattern extended from tree pattern. After definition, simplification, normalization, verification and initialization of the XPattern, both work sets and a join plan are generated. According to these measures, an effiective algorithm to answer for a twig query, called DMTwig, is designed without unnecessary elements and invalid structural joins. The algorithm can adaptively deal with twig queries with branch ([ ]), child edge (/), descendant edge (//), and wildcard (*) synthetically. We show that path-partitioned encoding scheme and XPattern guarantee the I/O and CPU optimality for twig queries. Experiments on representative data set indicate that the proposed solution performs significantly.

FPGA-Based High-Frequency Digital Pulse Width Modulator Architecture for DC-DC Converters

Digital pulse width modulator is an integral part in digitally controlled Direct Current to Direct Current (DC-DC) converter utilized in modern portable devices. This paper presents a new Digital Pulse Width Modulator (DPWM) architecture for DC-DC converter using mealy finite state machine with gray code encoding scheme and one hot encoding method to derive the variable duty cycle Pulse Width Modulation (PWM) signal without varying the clock frequency. To verify the proposed DPWM technique, the architecture with control input of six, five and four bits are implemented and the maximum operating frequency along with power consumption results is obtained for different Field Programmable Gate Array (FPGA) devices. The post layout timing results are presented showing that architecture can work with maximum frequency of 326 MHz and derive PWM signal of 3.59 MHz. Experimental results show the implementation of the proposed architecture in low-cost FPGA (Spartan 3A) with on-board oscillator clock frequency of 12 MHz which is multiplied internally by two with Digital Clock Manager (DCM) and derive the PWM signal of 1.5 MHz with a time resolution of 1 ps.