Purpose: This paper aims to summarize the influence law of hybrid deposited and micro-rolling (HDMR) technology on the shaping strain and residual stress. And the rolling parameters combination was further optimized to guide the actual production. Design/methodology/approach: This paper proposed a three-dimensional coupled thermo-mechanical model of the HDMR process. The validated model is used to investigate the influences of rolling parameters on stress and plastic strain (the distance between the energy source and roller [D_e–r], the rolling compression [c_r] and the friction coefficient [f_r]). The orthogonal optimization of three factors and three levels was carried out. The influence of rolling parameters on the plastic strain and residual stress is analyzed. Findings: The simulation results show that HDMR technology can effectively increase the shaping strain of the weld bead and reduce the residual tensile stress on the weld bead surface. Furthermore, the influence of rolling parameters on stress and strain is obtained by orthogonal analysis, and the corresponding optimal combination is proposed. Also, the rolling temperature significantly affects the residual stress, and the rolling reduction has a substantial effect on the plastic deformation. Research limitations/implications: Owing to the choice of research methods, this paper failed to study microstructure evolution. Originality/value: This paper provides a reference principle for the optimal selection of rolling parameters in HDMR.

The design and analysis of a dual-operating mode laterally diffused metal-oxide semiconductor (LDMOS) power amplifier for code-division multiple-access wireless communication base-station applications is presented in this paper. The amplifier structure consists of four parallelly located single-stage LDMOS amplifier array, the dual-mode input power divider, and output power combiner. In this dual-mode operation, the number of operating power amplifier (either one or four amplifiers) is controlled depending on the required power level. This results in significant improvement in efficiency performance of the amplifier by minimizing unnecessary dc power consumption. In addition to the enhancement of efficiency, the amplifier design approach also provides better overall linearity performance. The proposed dual-operating mode design technique was successfully demonstrated by designing, implementing, and testing an LDMOS power amplifier with Motorola MRF 21030 in this study

Purpose: This paper aims to summarize the influence law of hybrid deposited and micro-rolling (HDMR) technology on the bead morphology and overlapping coefficient. A better bead topology positively supports the overlapping deposited in multi-beads between layers while actively assisting the subsequent layer's deposition in the wire and arc additive manufacturing (WAAM). Hybrid-deposited and micro-rolling (HDMR) additive manufacturing (AM) technology can smooth the weld bead for improved surface quality. However, the micro-rolling process will change the weld bead profile fitting curve to affect the overlapping coefficient. Design/methodology/approach: Weld bead contours for WAAM and HDMR were extracted using line lasers. A comparison of bead profile curves was conducted to determine the influence law of micro-zone rolling on the welding bead contour and fitting curve. Aiming at the optimized overlapping coefficient of weld bead in HDMR AM, the optimal HDMR overlapping coefficient curve was proposed which varies with the reduction based on the best surface flatness. The mathematical model for overlapping in HDMR was checked by comparing the HDMR weld bead contours under different rolling reductions. Findings: A fitting function of the bead forming by HDMR AM was proposed based on the law of conservation of mass. The change rule of the HDMR weld bead overlapping spacing with the degree of weld bead rolling reduction was generated using the flat-top transition calculation for this model. Considering the damming-up impact of the first bead, the overlapping coefficient was examined for its effect on layer surface flatness. Originality/value: Using the predicted overlapping model, the optimal overlapping coefficients for different rolling reductions can be achieved without experiments. These conclusions can encourage the development of HDMR technology.

Power efficient UWB pulse generation techniques have been introduced. A simple, compact, and efficient RF pulse compression technique based on a switched resonator concept is used for the pulse generation. It utilizes different charging/discharging speeds of the circuit resonator by varying the resonator's Q factor and can be applied to any other microwave resonators. The approach compresses the duration of the pulse envelope without changing the phase characteristics of the RF carrier. The paper discusses the basic theory of switched resonators and the methodology of designing then for UWB pulse generation and compression

Ovarian cancer (OC) has a limited immunotherapeutic response; hence, this study aimed to investigate the relationship between CXC-chemokine ligand 13 (CXCL13) expression and overall survival (OS) rate, key immune pathways, degree of immune cell infiltration, and progressive disease (PD)-1 checkpoint blockade. A total of 703 differentially expressed genes were obtained from “The Cancer Genome Atlas” (TCGA) database based on the immune and stromal scores of 379 OC patients for getting the targeted gene CXCL13. The association between CXCL13 and OS in OC patients, biological function annotation of CXCL13, and its correlation with immune components were assessed. The results indicated that upregulated CXCL13 expression was positively correlated with better OC patient prognosis. CXCL13 expression was associated with 6 immune-related pathways, 10 immune cells, and PD-1 expression of OC micro-environment. Moreover, high expression of CXCL13 was related to a better tumor response and more extended tumor-stable stage after PD-1 blocking therapy in IMvigor210. The study concluded that CXCL13 could be a prognostic marker and a potential immunotherapy target for OC patients, especially PD-1 checkpoint blockade.