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[Objectives] With the continuous improvement of the electrification level of the Integrated Power System(IPS), real-time acquisition of equipment information and intelligent control of ships are prerequisites for ensuring safe and stable operation of equipment and correct decision-making.[Methods] In this paper,a dual-CPU-based dual Ethernet and dual RS-422 interactive communication system was built,and the hardware and software implementation of this interactive communication system was studied.[Results] It can quickly switch to the standby network in the event of a fault,thereby ensuring real-time transmission of on-site information and enhancing the anti-jamming capability and communication reliability of the system.[Conclusions] The communication system has high use value in the occasions where real-time online monitoring and data transmission are required,such as in the ship's integrated power energy management system,distributed substation,power conversion device and industrial field monitoring system.

[Objectives] In order to obtain multiple magnetical signature in different directions of a ship's external environment in realtime so as to make a appropriate degaussing scheme and provide data base for ship to realize magnetic stealth smoothly,a distributed acquisition system of dual-ring network is constructed.[Methods] The system is based on ARM(Advanced RISC Machine)embeded architecture with STM32F4 series chips as the microcontroller,which can obtain realtime magnetic data of 128 channels in the field and transmit them to the centralized control center/host computer by virtue of Ethernet communication technology.[Results] The system can pre-process the magnetic field data of different parts of the ship and transmit them to the centralized control center/host computer through optical fiber dual-ring network for subsequent processing.[Conclusions] The field operation tests show that the data acquisition system can reliably and accurately acquire multi-channel and big data in real time and has the value of extended application.

[Objectives] The ship transformer is the key to the safe,stable and reliable operation of a large ship integrated power system,so serious faults must be avoided.[Methods] Based on the Advanced RISC Machine(ARM),a transformer status online monitoring and fault diagnosis system was constructed. Anti-interference and data processing are used to ensure real-time,reliable and accurate acquisition of operational status data. Diagnostic system data analysis is used to accurately predict and identify fault types and trigger alarm,thereby ensuring timely action of the system to prevent faults from spread. Screen display is used to improve the dispatcher's ability to accurately grasp the operating status of the transformer.[Results] Multisim simulation modeling analysis and field operation test results show that the system can accurately collect the operating status data of the transformer,determine the type of transformer fault,and feedback it to the centralized control center in real time to formulate a reasonable control strategy and planning and scheduling scheme,thereby ensuring the normal operation of the ship integrated power system.[Conclusions] The research results can provide reference for on-line monitoring and fault diagnosis of ship transformers.

To link to full-text access for this article, visit this link: http://dx.doi.org/10.1016/j.solener.2005.09.002 Byline: Hongfei Zheng (a), Kaiyan He (b), Yinjun Yang (a), Ziqian Chen (a)(b), Hui Li (c) Keywords: Solar desalination; Falling film evaporation and condensation; Multi-effect regeneration; Integral-type Abstract: Based on the analysis of the mechanism of falling film evaporation and condensation, a new solar desalination unit with three effects regeneration was designed. The performance of the unit was tested through in-door experiments, using an electric heater as heat source. The results indicate that the unit has relatively high performance ratio because of a considerable fraction of the latent heat of condensation and the sensible heat of the warm condensate being successfully utilized three times to preheat and evaporate the feedstock. The unit has also excellent transient-state performance because of using the thin layer evaporation and falling film condensation which are the most effective processes for heat and mass transfer. When the operation temperature is over 90[degrees]C and the inner pressure is below 15kPa, the performance ratio of the unit can reach about 2.35 and its yield ratio can reach about 135kg/h. The main factors influencing the performance of the unit were researched and analyzed. The reasonable ranges of some parameters were presented. Author Affiliation: (a) School of Mechanical and Vehicular Engineering, Beijing Institute of Technology, Beijing 100081, China (b) School of Physics Science and Technology, Guangxi University, Nanning, Guangxi 530004, China (c) Department of Thermal Energy Engineering, Tsing Hua University, Beijing 100084, China Article History: Received 10 January 2005; Revised 25 August 2005; Accepted 2 September 2005 Article Note: (miscellaneous) Communicated by: Associate Editor P. Gandhidasan

We present a detailed study on the crystal structure of 0.10 mol% Ta-doped β-Ga2O3 crystals before and after annealing treatment in air by high-resolution X-ray diffraction and Raman spectroscopy, as well as the detection of point defects through the variation of photoluminescence excitation (PLE) and photoluminescence (PL) with temperature. Based on the experimental data, the band diagram of the 0.10 mol% Ta-doped β-Ga2O3 crystal is constructed. The crystal quality of the 0.10 mol% Ta-doped β-Ga2O3 crystal was improved after annealing treatment. The PL spectra exhibited two ultraviolet emission bands (UV ∼3.59 eV, UV′ ∼3.22 eV) and a blue emission band (BB ∼2.73 eV) , which are ascribed to the recombination of self-trapped excitons at the trigonal OI and OII sites and gallium vacancies in the (2−) charge state (tetrahedral site), respectively. The work function of the 0.10 mol% Ta-doped β-Ga2O3 crystal increased from 5.28 eV to 5.38 eV as a result of annealing treatment. [ABSTRACT FROM AUTHOR]

Three types of congregated solar concentrators or so-called light funnels have been designed. They are a Compound Parabolic Concentrators (CPC) superposed light funnel, a CPC superposed light funnel with a deflector and a mirror focus superposition light funnel. Their light-concentrating principle and light conduction process have been analyzed. Their performances have been discussed after testing under real weather conditions, and also their conducting light rates and curve of conducting light performance for different incident angles have been calculated. The experimental results show that the conducting light rate of the mirror focus superposition-type light funnel is maximum, up to 35.1%. The CPC superposed light funnel has a minimum value, with only 25.6%. The CPC superposed light funnel is the most demanding regarding tracking accuracy. The other two types of concentrators are less demanding concerning tracking accuracy. [ABSTRACT FROM PUBLISHER]

Systematic investigations are performed to understand the temperature-dependent optical properties of graphene on Si and SiO2/Si substrates by using a variable angle spectroscopic ellipsometry. The optical constants of graphene have revealed changes with the substrate and temperature. While the optical refractive index (n) of monolayer graphene on Si exhibited clear anomalous dispersions in the visible and near-infrared region (400–1200 nm), the modification is moderate for graphene on SiO2/Si substrate. Two graphene sheets have shown a pronounced absorption in the ultraviolet region with peak position related to the Van Hove singularity in the density of states. By increasing the temperature from 300 K to 500 K, for monolayer graphene on Si, the n value is gradually increased while k decreased. However, the optical constants [n, k] of monolayer graphene on SiO2/Si exhibited unpredictable wave variations. In the wavelength range of 400–1200 nm, an experiential formula of a like-Sellmeier equation is found well suited for describing the dispersions of graphene on Si and SiO2/Si substrates. [ABSTRACT FROM AUTHOR]

Humans possess a remarkable ability to rapidly access diverse information from others' faces with just a brief glance, which is crucial for intricate social interactions. While previous studies using event-related potentials/fields have explored various face dimensions during this process, the interplay between these dimensions remains unclear. Here, by applying multivariate decoding analysis to neural signals recorded with optically pumped magnetometer magnetoencephalography (OPM-MEG), we systematically investigated the temporal interactions between invariant and variable aspects of face stimuli, including race, gender, age and expression. First, our analysis revealed unique temporal structures for each face dimension with high test-retest reliability. Notably, expression and race exhibited a dominant and stably maintained temporal structure according to temporal generalization analysis. Further exploration into the mutual interactions among face dimensions uncovered age effects on gender and race, as well as expression effects on race, during the early stage (around 200-300 ms post face presentation). Additionally, we observed a relatively late effect of race on gender representation, peaking around 350 ms after stimulus onset. Taken together, our findings provide novel insights into the neural dynamics underlying the multi-dimensional aspects of face perception and illuminate the promising future of utilizing OPM-MEG for exploring higher-level human cognition. Significance statement In everyday social activities, people can quickly interpret a wide range of information from others' faces. Although converging evidence has shed light upon the neural substrates underpinning the perception of invariant and variable aspects of faces, such as race, gender, age and expression, it is still not fully understood how the information of one face dimension alters the perception of another. In this study, we utilized multivariate decoding analysis on neural activity captured through OPM-MEG during face perception. Our approach enabled a comprehensive exploration of the temporal interactions among different face dimensions, providing an improved understanding of the temporally structured neural dynamics that support the multi-dimensional face perception in the human brain., (Copyright © 2024 the authors.)