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Gallium nitride high-electron-mobility transistor (GaN HEMT) power devices are favored in various scenarios due to their high-power density and efficiency. However, with the significant increase in the heat flux density, the junction temperature of GaN HEMT has become a crucial factor in device reliability. Since the junction temperature monitoring technology for GaN HEMT based on temperature-sensitive electrical parameters (TSEPs) is still in the exploratory stage, the TSEPs' characteristics of GaN HEMT have not been definitively established. In this paper, for the common steady-state TSEPs of GaN HEMT, the variation rules of the saturation voltage with low current injection, threshold voltage, and body-like diode voltage drop with temperature are investigated. The influences on the three TSEPs' characteristics are considered, and their stability is discussed. Through experimental comparison, it is found that the saturation voltage with low current injection retains favorable temperature-sensitive characteristics, which has potential application value in junction temperature measurement. However, the threshold voltage as a TSEP for certain GaN HEMT is not ideal in terms of linearity and stability. [ABSTRACT FROM AUTHOR]

Unlike the concentrated load in urban area base stations, the strong dispersion of loads in suburban or highway base stations poses significant challenges to traditional power supply methods in terms of efficiency and cost. High-voltage direct current (HVDC) remote supply have better application potential in this scenario due to their low transmission losses, attracting much attention. However, existing research has problems such as ambiguous optimal power supply distance under different voltage levels and a lack of behavioral models for converters. Therefore, this paper starts from the behavior of underlying converters, analyzes the loss composition of different converters in HVDC long-distance supply, and establishes a refined model for converters by determining the mathematical relationship between converter losses and operating power. Considering the economic feasibility of power supply solutions throughout the lifecycle, a modeling method is proposed that optimizes the voltage level of converters considering the behavior of converters for different supply distances. The optimal voltage level for different supply distances is discussed, and the effectiveness of the model is verified through examples, providing valuable guidance for optimizing the voltage level in HVDC long-distance supply for 5G base stations. [ABSTRACT FROM AUTHOR]

All-solid-state batteries (SSBs) are prospective candidates for a range of energy accumulation systems, delivering higher energy densities compared to batteries which use liquid electrolytes. Amongst the numerous solid-state electrolytes (SEs), sulfide-based electrolytes in particular have received more attention given that they have a high ionic conductivity. However, the incompatibility between the electrode and SEs is still an ongoing challenge that leads to poor electrochemical performance. In this work, we focus on 1T-MoS2. It is well known that 1T metallic MoS2 is unstable even at room temperature. However, we showed that 1T-MoS2 can be stabilized at 600 °C for at least 2 h, and the 1T-MoS2-600 interlayer spacing expanded to 0.95 nm. The high crystallinity of the 1T phase is highly compatible with solid electrolytes and coupled with the increased interlayer spacing, so in the all-solid-state lithium-ion battery (ALLLIB), we achieved outstanding cycling performance. At the current density of 0.2 C (1 C = 670 mA g−1), this material delivered a capacity of 406 mA h g−1 after 50 cycles. [ABSTRACT FROM AUTHOR]

Gate-oxide degradation has been one of the critical reliability concerns of silicon carbide (SiC) metal–oxide–semiconductor-field-effect transistors (mosfets), which could be monitored through aging-sensitive parameters. In this article, an online gate-oxide degradation monitoring method for planar SiC mosfets is proposed by extracting gate charge time at a specific range of gate voltage. It is based on the findings that the input capacitances of planar SiC mosfets change significantly over gate-oxide degradation, which is theoretically analyzed and experimentally verified. The capacitance variations are converted into the gate charge time as the new aging-sensitive parameter. The new parameter measurement circuit is proposed and integrated into the gate driver module. The article results indicate that the new parameter varies noticeably with gate-oxide degradation and the difference of this parameter caused by junction temperature is much smaller than that caused by degradation. Besides, the parameter is immune to package degradation and load current. The condition monitoring method can be implemented online since the parameter is extracted during the off-state of SiC mosfet devices, which does not affect normal operation. The confirmatory experiment is carried out to verify the correctness of the proposed method. [ABSTRACT FROM AUTHOR]

The dynamic design of graphic language can be seen everywhere in life as the digital media era progresses. Graphic designs, such as product packaging, poster design, book binding design, and logo design, are examples of traditional visual design. The print media is the most important factor. Graphic design that is aided by digital media technology is not limited to print but also includes network media. The teaching research of China's visual design specialty is still in its early stages, the relevant teaching system reform of various colleges and universities is still being explored, and there is no unified standard in the digital information age. As a result, it is critical to conduct in-depth research using scientific and systematic methods in order to pave the way for the development of a domestic visual design specialty in the information age. Simultaneously, the popularization and development of new media have had a significant impact on traditional printing media, breaking the monotony of traditional visual communication and making modern visual design more vivid and intuitive. Visual perception in psychology is introduced into design thinking in this paper. Apart from its expression in art culture, the concept of space also encompasses the physics concepts of time and space, as well as the scientific research theory of visual perception in psychology, which transcends the perceptual cognition level of space in art design. [ABSTRACT FROM AUTHOR]

In a virtual 3D city scene, a 3D building model is a must-have element. A 3D reconstruction and rendering algorithm is described in this paper. Model geometry and texture data are simplified separately using LOD model technology. Half-folded mesh algorithm is used to simplify geometric data, while wavelet algorithm is used to compress texture data. Both methods reduce the amount of data that must be stored as well as the amount of data that must be transmitted over the network. To improve the response time of the original algorithm, a Kalman filter correction algorithm is used to optimize the 3D reconstruction beam adjustment algorithm. In this paper, the experimental scheme is used to assess the method. Experiments show that the algorithm reduces the number of primitives drawn by the system while preserving the important geometric features of the scene's building model. It can also effectively reduce the workload of drawing 3D scenes, improve computer productivity, and reduce computer hardware requirements. This technique is well suited to rendering large-scale 3D urban scenes. [ABSTRACT FROM AUTHOR]

Crack-induced changes in the aeroelastic boundaries of an unswept composite wing are investigated. The bendingtorsion couplings due to the unbalanced laminates and offset of the center of gravity are incorporated into the equation of motion. The edge crack, modeled with the local flexibility concept, introduces additional boundary conditions at the crack location. The fundamental modes of the intact and cracked beam are used in Galerkin's method, and the approximate solution for flutter and divergence speeds is obtained with steady and quasi-steady aerodynamic forces applied. Changes in flutter and divergence speeds (with respect to the crack ratio and its location, along with the fiber orientation) are compared. In many cases, the existence of an edge crack imposes detrimental effects on the aeroelastic boundaries, although it may increase the flutter and/or divergence speed when fibers are orientated at certain angles. The results may help composite wing designers in their aeroelastic tailoring and structural engineers in designing damage prognosis tools to predict the health status of composite wing structures.

Monitoring the defective multichip insulated gate bipolar transistor (IGBT) module is a cost-effective approach to improve the quality of customer service. A method using time duration of the gate charge is proposed to monitor bond wires fatigue of the multichip IGBT modules when the modules are in the off-state. It is based on the fact that failure of the chip branch due to bond wires fatigue changes the gate input capacitance of the multichip IGBT module. The health state of bond wires can be converted into the change of time duration of gate charge under the constant gate current. A driver containing the constant current source is proposed. The study results indicate that the time duration of the gate charge decreases significantly when the failure of the chip branch occurs, and the effect of junction temperature can be ignored within the special range of gate voltage. Condition monitoring can be implemented during the off-state of the multichip module and without considering the effects of junction temperature. The confirmatory experiment is carried out to verify the correctness of the proposed method. [ABSTRACT FROM AUTHOR]

The junction temperature fluctuation of an insulated-gate bipolar transistor (IGBT) is the most important factor of its aging failure, and smoothing the fluctuation is an effective way to improve the life of an IGBT. The existing methods for smoothing the fluctuation by active junction temperature control are not yet ready wide application, and exploring the different approaches to active junction temperature control is a hot topic. This paper presents a method of active junction temperature control that shifts the turn-off trajectory of an IGBT to adjust the IGBT turn-off loss for smoothing the junction temperature. The relationship between parameters of the adjusting circuit and turn-off loss is analyzed. On the basis of this analysis, a method of estimating the smoothing ability for the proposed active junction temperature control is deduced. Using an IGBT installed in a 1.2-MW direct-drive wind power converter as an example, the evaluation result shows that the proposed method can completely smooth the junction temperature fluctuation caused by a 40% rated load fluctuation. Finally, a low-power experiment is carried out. [ABSTRACT FROM PUBLISHER]

Normally entrepreneur would raise fund from angel investors during the initial round. If the venture program was by then successful, the entrepreneur would then continue the fund-raising process from venture capitalist. By adopting the convertible preferred stock, we managed to construct the two-stage angel investment decision process. This research reveals the following: (1) The probability of the first stage’s success has negative relationships with levels of priority dividend in both first and second stages, as well as with the venture capitalist’s proportion of shares. (2) The probability of the second stage’s success has negative relationships with the venture capitalist’s proportion of shares and the dividend level of both first and second stage funding. (3) There has been a threshold of dividend distribution, which belongs to angel investor. While the level of angel investor’s shares is higher than the threshold, AN would decide to join the second phase of the program; otherwise, AN would exit the project at the end of the first stage. [ABSTRACT FROM AUTHOR]

Bladder urothelial carcinoma (BLCA) accounts for 95% of all cases of bladder cancer worldwide, with a high incidence and poor prognosis. Chromobox (CBX) proteins play a key role in numerous malignant tumors; however, the role of CBX in BLCA remains unknown. Herein, the present study found that, compared with in normal bladder tissues, the expression levels of CBX1, CBX2, CBX3, CBX4 and CBX8 were markedly increased in BLCA tissues, as determined by Tumor Immune Estimation Resource, UALCAN and ONCOMINE analyses, whereas CBX6 and CBX7 were decreased in BLCA tissues. Furthermore, evident hypomethylation in the promoters of CBX1, and CBX2, as well as significant hypermethylation in the promoters of CBX5, CBX6 and CBX7, was detected in BLCA tissues compared with in normal bladder tissues. The expression of CBX1, CBX2 and CBX7 was involved in the prognosis of patients with BLCA. Low CBX7 expression was strongly associated with poorer overall survival in patients with BLCA, whereas high CBX1 and CBX2 expression was associated with poorer progression-free survival. Besides, significant associations were determined between the expression of CBXs and immune cell infiltration, including dendritic cells, neutrophils, macrophages, CD4+ T cells, CD8+ T cells and B cells. Overall, the current results may provide a rationale for developing new targets and prognostic markers for BLCA therapy. [ABSTRACT FROM AUTHOR]

When venture capital has been invested into venture companies, venture capitalists and venture entrepreneurs form a principal-agent relationship. Take into account the fact that the venture entrepreneur’s effort is a long process, because the effort is not the same at different stage. Therefore, efforts variables are seen as the multistage dynamic variable, and venture investment principal-agent model with venture entrepreneurs having multistage efforts is constructed on the basis of the classic principal-agent theory in the paper. Further, in the later stage effort of venture entrepreneurs is affected by the size of prestage benefit with venture capitalists and venture entrepreneurs; thus the fairness preference model is improved, and venture investment principal-agent model with venture entrepreneurs having multistage efforts is constructed on the basis of fairness preference theory. Both theoretical derivation and simulation have demonstrated that, under the condition of information asymmetry, if the fairness preference of venture entrepreneurs holds, then (1) venture capitalists provide venture entrepreneurs with level higher than that without fairness preference, (2) in every single stage venture entrepreneurs make efforts higher than those without fairness preference, and (3) in two periods both venture investors and venture entrepreneurs gain total real gains higher than those in two periods without fair preference. [ABSTRACT FROM AUTHOR]

Background: The prognosis for patients with kidney renal clear cell carcinoma (KIRC) remains unfavorable, and the understanding of SRY-box transcription factor 11 (SOX11) in KIRC is still limited. The purpose of this paper is to explore the role of SOX11 in the prognosis of KIRC., Methods: We analyzed SOX11 expression in KIRC and adjacent normal tissues using The Cancer Genome Atlas (TCGA) and Gene Expression Omnibus (GEO) databases. Our study aims to establish a correlation between SOX11 expression and clinical pathological features. Differentially expressed genes (DEGs) were assessed using R software. Furthermore, we conducted Gene Ontology (GO)/Kyoto Encyclopedia of Genes and Genomes (KEGG) analyses and gene set enrichment analysis (GSEA). Integration of data from the Tumor Immune Estimation Resource (TIMER) and TCGA databases allowed us to assess the association between SOX11 expression and immune infiltration in KIRC. Additionally, we analyzed the association between SOX11 gene expression and N6-methyladenosine (m6A) modification in KIRC using TCGA and GEO data., Results: Our findings revealed high SOX11 expression in KIRC, which showed a significant correlation with tumor staging and prognosis. GO/KEGG and GSEA analyses indicated that SOX11 was closely associated with sodium ion transport, synaptic vesicle circulation, and oxidative phosphorylation. Analysis of the TIMER and TCGA databases demonstrated correlations of SOX11 expression levels with the presence of CD8 + T lymphocytes, neutrophils, CD4 + T cells, as well as B cells. Moreover, both the TCGA and GEO datasets showed a substantial association between SOX11 and m6A modification-related genes, namely ZC3H13 , FTO , METTL14 , YTHDC1 , IGF2BP1 , and IGF2BP2 ., Conclusions: SOX11 exhibits a correlation with m6A modification and immune infiltration, suggesting its potential as a prognostic biomarker for KIRC., Competing Interests: Conflicts of Interest: All authors have completed the ICMJE uniform disclosure form (available at https://tcr.amegroups.com/article/view/10.21037/tcr-24-109/coif). The authors have no conflicts of interest to declare., (2024 Translational Cancer Research. All rights reserved.)

Objective: To compare our initial perioperative and postoperative outcomes of the modified anterior approach (MA) with Retzius space preservation robot-assisted radical prostatectomy (RARP) with the standard anterior approach (SA) RARP., Materials and Methods: A retrospective analysis was performed on 116 patients with RARP completed by the same surgeon between September 2019 and March 2022. They were divided into SA-RARP group (77 cases) and MA-RARP group (39 cases). Propensity score matching was performed using eight preoperative variables, including age, BMI, preoperative PSA, biopsy Gleason score, prostate volume, D'Amico risk classification, SHIM, and clinical T stage. Functional outcome was assessed by urine pad count and SHIM after surgery, and oncological outcome was assessed by statistics of postoperative pathological findings as well as follow-up postoperative PSA. The median follow-up was 13 months and 17 months for MA-RARP and SA-RARP groups respectively., Results: Propensity score matching was performed 1:1, and baseline data were comparable between the two groups after matching. Comparison of postoperative data: MA-RARP group had less mean EBL than SA-RARP group (200 vs 150 ml, p = 0.033). PSM did not differ between groups (p = 1). In terms of urinary control recovery, the MA-RARP group showed significant advantages in urinary control recovery at 24 h, 2 weeks, 1 month and 3 months after catheter removal, respectively (48.6% vs 5.7%, p < 0.001; 80% vs 22.9%, p < 0.001; 94.3% vs 51.4%, p < 0.001; 100% vs 74.3%, p = 0.002). This advantage gradually disappeared 6 months or more after surgery. The median time to recovery of sexual function was shorter in the MA-RARP group (165 vs 255 d, p = 0.001)., Conclusion: MA-RARP is safe and reliable, and can achieve better early urinary control function and sexual function recovery while achieving the primary tumor control goal., Competing Interests: The authors declare that the research was conducted in the absence of any commercial or financial relationships that could be construed as a potential conflict of interest., (Copyright © 2023 Li, Yang, Liao, Wang, Zhang and Cao.)