In this paper, a duty-varied voltage pulse-charge strategy (DVVPCS), that can detect and dynamically track the suitable duty of the charge pulse, is proposed to improve the battery-charge ...performance. To assess the system performance, a prototype of the duty-varied voltage pulse charger (DVVPC) is designed and implemented. Comparing with the standard constant-current and constant-voltage (CC-CV) charge strategy, the charge speed of the proposed DVVPCS is improved by about 14%, while the proposed DVVPCS is improved by about 5% in comparison with the conventional duty-fixed voltage pulse-charge strategy (DFVPCS). The charge efficiency of the proposed DVVPC has been improved by about 3.4% as compared with that of the general CC-CV. In comparison with conventional DFVPCS with D = 50%, the charge efficiency of the proposed DVVPCS is improved by about 1.5%. The results indicate that the DVVPCS can actually provide pulse with suitable duty to charge the battery, and the charge performance is improved.
In addition to a high specific capacitance, a large stretchability and self‐healing properties are also essential to improve the practicality and reliability of supercapacitors in portable and ...wearable electronics. However, the integration of multiple functions into one device remains challenging. Here, the construction of a highly stretchable and real‐time omni‐healable supercapacitor is demonstrated by sandwiching the polypyrrole‐incorporated gold nanoparticle/carbon nanotube (CNT)/poly(acrylamide) (GCP@PPy) hydrogel electrodes with a CNT‐free GCP (GP) hydrogel as the electrolyte and chemically soldering an Ag nanowire film to the hydrogel electrode as the current collector. The newly developed dynamic metal‐thiolate (M‐SR, M = Au, Ag) bond‐induced integrated configuration, with an intrinsically powerful electrode and electrolyte, enables the assembled supercapacitor to deliver an areal capacitance of 885 mF cm−2 and an energy density of 123 µWh cm−2, which are among the highest‐reported values for stretchable supercapacitors. Notably, the device exhibits a superhigh stretching strain of 800%, rapid optical healing capability, and significant real‐time healability during the charge–discharge process. The exceptional performance combined with the facile assembly method confirms this multifunctional device as the best performer among all the flexible supercapacitors reported to date.
A highly stretchable and real‐time omni‐healable supercapacitor is constructed by synergistically designing the entire device from the microstructures of the hydrogel electrode and electrolyte, to the interfacial interactions among the current collector, electrode, and electrolyte, and further to all‐in‐one device configuration via dynamic metal‐thiolate coordination chemistry. This supercapacitor shows great potential in the field of next‐generation flexible/wearable electronics.
In this research the authors examine members' voluntary use of social networking sites. Site use leads to the growth of social relationships, increased volume of site visits and traffic, and an ...accumulation of user generated contents; hence it is imperative to the success of social networking sites. Drawing upon Social Exchange Theory (SET), we develop a research model that examines the major determinants of member site use behavior through a cost-benefit framework. This model also investigates the key antecedents to site use that stem from website designs, personal traits, and personal beliefs in the environment. The research model has been validated through survey data collected from 222 social networking site users, and the analysis results provide strong support to the hypothesized relationships. The current study generates new knowledge on the literature of SET and social networking sites; it also sheds lights on site management for networking service providers.
► Perceived enjoyment is a key benefit to the users of social networking sites and it promotes site use ► Perceived risk is a major cost to the users of social networking sites and it hinders site use ► Perceived risk reduces the impact of perceived enjoyment on individual's use of networking sites ► Social presence, ease of use, and extroversion enhance the perceived enjoyment ► Internet risk perception and privacy abuse concern increase the perceived risk
In order to better disseminate Hakka culture, this thesis focuses on the cultural dissection of Hakka culture in Gannan and the development and reflection of Hakka culture in Gannan. This article ...aims to design the brand image of Hakka culture through human–computer interaction model. And based on this, this article discusses the brand concept and the elements of cultural and creative products and discusses the connection between Hakka cultural and creative and tourism brands. At the same time, this article conducts an in-depth study on the creative design of the Hakka cultural tourism brand in Gannan. First, this article analyzes the brand connotation and analyzes the connotation and constituent elements of brand cultural and creative products. Second, this article analyzes the relationship between Hakka culture and tourism brand cultural and creative product design. It discusses how to inherit and develop Hakka culture from the perspective of how Hakka culture is integrated into brand cultural and creative products. Third, this article analyzes the design practice of cultural and creative products of the Hakka cultural tourism brand in Gannan. This article first analyzes the visual image design of the cultural and creative products of the Hakka cultural tourism brand in Gannan. Then it analyzes the design of a series of cultural and creative products of the Hakka cultural tourism brand in Gannan. The experimental results show that the popularity of different products is more than 50%, which shows the effectiveness of this design.
It is still a great challenge to achieve high selectivity of CH4 in CO2 electroreduction reactions (CO2RR) because of the similar reduction potentials of possible products and the sluggish kinetics ...for CO2 activation. Stabilizing key reaction intermediates by single type of active sites supported on porous conductive material is crucial to achieve high selectivity for single product such as CH4. Here, Cu2O(111) quantum dots with an average size of 3.5 nm are in situ synthesized on a porous conductive copper‐based metal–organic framework (CuHHTP), exhibiting high selectivity of 73 % towards CH4 with partial current density of 10.8 mA cm−2 at −1.4 V vs. RHE (reversible hydrogen electrode) in CO2RR. Operando infrared spectroscopy and DFT calculations reveal that the key intermediates (such as *CH2O and *OCH3) involved in the pathway of CH4 formation are stabilized by the single active Cu2O(111) and hydrogen bonding, thus generating CH4 instead of CO.
Cu2O(111) single‐type sites on a conductive metal–organic framework are successfully prepared by an in situ electrochemical method. The cooperative effect between the single active Cu2O(111) and hydrogen bonding contributes to the high selectivity of 73 % towards CH4 with large current density in CO2 electroreduction reduction for the obtained Cu2O(111)@CuHHTP.
Good advanced food traceability systems help to minimize unsafe or poor quality products in food supply chain through value-based process. From the emerging technologies forthcoming for industry ...automation, future advanced food traceability system must consider not only cyber physical system (CPS) and fog computing but also value-added business in food supply chain. Accordingly, this study presents a novel intelligent value stream-based food traceability cyber physical system approach integrated with enterprise architectures, EPCglobal and value stream mapping method by fog computing network for traceability collaborative efficiency. Furthermore, the proposed intelligent approach explores distributive and central traceable stream mechanism in assessing the most critical traceable events for tracking and tracing process. Successful case study, software system design and implementation demonstrated the performance of the proposed approach. Furthermore, experiment shows the better results obtained after the simulation execution for intelligent predictive algorithm.
•A novel intelligent value stream-based food traceability cyber physical system is created.•This paper describes a distributive and central traceable stream mechanism for traceability process.•The EA, EPCglobal and VSM methods by fog computing are used traceability efficiency.•The proposed approach aimed at optimizing complex CPS-based food traceability system in food supply chain.•This paper explores information system design architecture of intelligent CPS-based food traceability system.
In recent years, more and more inflammatory indicators have been studied to predict the long-term survival of patients with ampullary carcinoma (AC) after radical resection, but these prognostic ...indicators are still controversial. Therefore, based on previous inflammation scores, this study established a novel, easily accessible, more feasible and more predictive prognostic marker Carbohydrate antigen199 to gamma-glutamyltransferase ratio (CA19-9/GGT) to better assess the prognostic significance in AC patients undergoing radical resection.
Overall survival (OS) and recurrence-free survival (RFS) were analyzed by Cox regression model. Correlation between CA19-9/GGT and clinicopathological variables were analyzed by Chi-squared test, Fisher ' s exact test, independent sample t test and Mann-Whitney U test. The performance of prognostic indexes is compared by the consistency index (C-index). The prediction accuracy of nomogram is further confirmed by calibration curve and decision curve analysis (DCA).
CA19-9/GGT was an independent risk factor affecting OS P = 0.001, hazard ratio (HR) 2.459, 95% confidence intervals (CI) 1.450-4.167 and RFS (P = 0.002, HR 2.333, 95% CI 1.371-3.971) in multivariate analysis. The optimal cut-off value of CA19-9/GGT was 0.14. In CA19-9/GGT correlation analysis, high risk group (> 0.14) was significantly associated with poor prognosis. The predictive performance of CA19-9/GGT (OS: C-index = 0.753, RFS: C-index = 0.745) was confirmed to be superior to other prognostic indicators according to the C-index. Compared with the simple AJCC staging system, the Nomogram prediction model (OS: C-index = 0.787, RFS: C-index = 0.795) established by the combination of CA19-9/GGT and AJCC 8th TNM staging system has higher prediction accuracy.
CA19-9/GGT was an independent prognostic indicator after radical resection of AC. Incorporating CA19-9/GGT into the AJCC TNM staging system optimized the prediction accuracy of the TNM staging system, and further verified the predictive value of CA19-9/GGT.
In this paper, a variable frequency pulse charge system (VFPCS), that can detect and dynamically track the optimal charge frequency, is proposed to improve the battery-charge response. To assess the ...system performance, a prototype of the VFPCS for 600-mAh lithium-ion battery is designed and implemented. Compared with the standard constant-current and constant-voltage charge system, the charge speed of the proposed VFPCS is improved above 24%, while the proposed VFPCS is improved above 10% compared with the conventional fixed-frequency pulse charge system. The results indicate that the VFPCS can actually provide pulse with optimal frequency to charge the battery and the charge response is improved
Combining Ising‐type magnetic anisotropy with collinear magnetic interactions in single‐molecule magnets (SMMs) is a significant synthetic challenge. Herein we report a Dy15‐MCCu‐5 (1‐Dy) SMM, where ...a DyIII ion is held in a central pseudo‐D5h pocket of a rigid and planar Cu5 metallacrown (MC). Linking two Dy15‐MCCu‐5 units with a single hydroxide bridge yields the double‐decker {Dy15‐MCCu‐5}2 (2‐Dy) SMM where the anisotropy axes of the two DyIII ions are nearly collinear, resulting in magnetic relaxation times for 2‐Dy that are approximately 200 000 times slower at 2 K than for 1‐Dy in zero external field. Whereas 1‐Dy and the YIII‐diluted Dy@2‐Y analogue do not show remanence in magnetic hysteresis experiments, the hysteresis data for 2‐Dy remain open up to 6 K without a sudden drop at zero field. In conjunction with theoretical calculations, these results demonstrate that the axial ferromagnetic Dy–Dy coupling suppresses fast quantum tunneling of magnetization (QTM). The relaxation profiles of both complexes curiously exhibit three distinct exponential regimes, and hold the largest effective energy barriers for any reported d–f SMMs up to 625 cm−1.
The magnetic hysteresis of a metallacrown magnet opens after introducing axial ferromagnetic by linking two mono‐decker Dy15‐MCCu‐5 units with a single hydroxide bridge to give the double‐decker {Dy15‐MCCu‐5}2 single‐molecule magnet in which the anisotropy axes of the two DyIII ions are nearly collinear and the magnetic relaxation times are approximately 200 000 times slower than for the mono‐decker unit.
Graph clustering aims to divide nodes into different clusters without labels and has attracted great attention due to the success of graph neural networks (GNNs). Traditional GNN-based clustering ...methods are based on the homophilic assumption, i.e., connected nodes belong to the same clusters. However, this assumption is not always true, as heterophilic graphs are also ubiquitous in the real world, which limits the application of GNNs. Furthermore, these methods overlook global positions, which can result in erroneous clustering. To solve the aforementioned problems, we propose a novel model called Preserving Global Information for Graph Clustering with Masked Autoencoders (GCMA). We first propose a low–high-pass filter to capture meaningful low- and high-frequency information. Then, we propose a graph diffusion method to obtain the global position. Specifically, a parameterized Laplacian matrix is proposed to better control the global direction. To further enhance the learning ability of the autoencoders, we design a model with a masking strategy that enhances the learning ability. Extensive experiments on both homophilic and heterophilic graphs demonstrate GCMA’s advantages over state-of-the-art baselines.
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