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The fatty acid (FA)/wood-flour (WF) composite form-stable phase change materials (PCMs) were prepared via a direct impregnation method, in which WF was selected as the supporting materials. The surface morphology, chemical structure, crystalline structure, phase change properties, thermal reliability and stability of the prepared FA/WF composite form-stable PCMs were investigated by scanning electron microscopy (SEM), Fourier transform infrared spectrometer (FTIR), X-ray diffraction (XRD), differential scanning calorimeter (DSC), accelerated thermal cycling testing and thermogravimetric analysis (TG), respectively. SEM images showed that the porous spaces of WF can be largely occupied by the impregnated FA without leakage. FTIR and XRD results suggested that there was no chemical reaction but only physical interactions between WF and FA. XRD analysis also demonstrated that the WF had no effect on the crystallization of FA. The prepared FA/WF composite PCMs had high latent heats and a suitable phase change temperature range, especially the maximum latent heats in melting and freezing process for the HW-FSPCM reached 102.6 J/g and 103.5 J/g. The prepared FA/WF composite PCMs exhibited comprehensive thermal reliability and stability from the thermal cycling test and TG analysis.

This paper addresses an Integrated Circuit Immunity Model-Conducted Immunity (ICIM-CI) of the embedded controller area network (CAN) controller in microcontroller to the conducted disturbances. The procedure is based on a gray-box approach to predict the behavior of a disturbed circuit. The parameters are estimated from time and frequency domain measurements, allowing accurate and efficient reproduction of nonlinear device switching behaviors. The immunity of the CAN controller is measured with the direct RF power injection method. The obtained model is successfully implemented to predict both the functional signals and the RF noise immunity at component level.

Objective Porcine liver extract has been shown to be effective in the clinical treatment of severe hepatitis. The aim of the present study was to study its antifibrotic as well as immune regulatory effect in vitro . Methods Hepatocytes, hepatic stellate cells (HSCs), hepatoma cell line (HepG2) and human peripheral blood mononuclear cells (PMNCs) were studied with respect to proliferation, extracellular matrix production and apoptotic activities by proliferation assay, radioimmunoassay, gene transfection, reporter gene analysis and flow cytometry, respectively. Results A strong stimulatory proliferation effect was observed in hepatocytes, and an inhibitory effect was found in HSCs. Hyaluronic acid (HA) production and reporter gene activities driven by various α1(I) procollagen gene promoters in HSC-T6 were significantly decreased after treatment with the extract. Fluo-Anexin V binding apoptotic HepG2 cells were more prominent in the presence of 60 μg/ml extract. More CD4 + /CD69 + positive T lymphocytes existed in the presence of the extract. Conclusion Porcine liver extract is effective for antifibrogenesis via hepatocyte regeneration, HSC and hepatoma cell inhibition in vitro . The elevation of active T lymphocytes is helpful for immune surveillance. Fine mapping of the extract is necessary in order to get definite molecules which are essential in all described functions.

Printed circuit board(PCB) designers require fast and accurate methods of simulating immunity of PCB to electrostatic discharge(ESD) events to adequately predict and analyze ESD issues. An efficient methodology for calculating the electromagnetic field coupling from ESD electromagnetic pulse(EMP) to PCB while fully considering the non-linear circuit elements in the PCB core is proposed in this paper. Voltages and currents within the PCB are found by merging full-wave simulations of ESD EMP with a SPICE model of the PCB and the coupled electromagnetic energy. This method was verified through experiments, results show the promise of the method. This hybrid modelling method can significantly accelerate simulation time compared with traditional modelling techniques and can allow the designers to explore the variation in coupling that occurs with small changes in the test setup better, such as the position and orientation of the EMP and PCB pins.

Electromagnetic compatibility (EMC) and compromising emanations (CE) are two centrally important aspects of computer systems closely related to security. This paper will discuss the EMC for functional safety, and investigate the risk of emission security on computer system architecture. Initially, the EMC issues for the electromagnetic emission of computer as well as the susceptibility of tremendously increased critical circuits are presented. Then, impact of electromagnetic security in ubiquitous applications based on computer technology is discussed, which encompasses the damage of electromagnetic environment effects (E3), CE or TEMPEST example and emission limits requirements. Finally, the protection means of computer functional security are provided. The paper states the need for the guidelines on controlling EMC and the process of CE to achieve electromagnetic security of computer systems.

In order to improve compatibility at chip and system level, the electromagnetic compatibility (EMC) of digital signal controllers (DSCs) is analyzed in this paper. The EMC issues of DSCs, related to emission and susceptibility for chip including multiple complex peripherals running at fairly high-clock frequencies, and EMC control approach are considered. The DSCs electromagnetic model is proposed to achieve the emission simulation and susceptibility analysis at the chip level, and it is possible to estimate the effect of disturbances on the measurement and control systems. Finally DSC circuit design for EMC compliance has enhanced their reliability.

With the increase in modern communication based on wireless technology, protection against electromagnetic environment effects (E3) on systems is becoming more important. This includes reducing the electromagnetic interference (EMI) and ensuring compatibility for communication systems within, and especially protecting data links and terminals against lightning and high-power electromagnetic pulse (HEMP) to achieve the normal operation of these systems. This paper focuses on E3 analysis, design and operation to protect electronic equipment and communication network systems, and is of value in ensuring effective performing that mission in todaypsilas complex electromagnetic environments (EME).

Modern High performance control applications demanded from mixed-signal and digital signal processors (DSPs) are ever increasing. As digital circuits and DSP operate at a higher rate, a considerable amount of noise and radiation degrades the system?s performance and creates EMI problems that make it difficult to pass tests required to obtain certification by the EMC regulations. In this paper, we introduce some effective methods for reduced EMI of the measurement and control systems, which are power supply design, clock and phase-locked loop (PLL) isolation, decoupling techniques, digital and analog partitioning, printed circuit board (PCB) layout, and so on for meeting many challenges of mixed-signal and DSP systems design. Design guidelines for improved EMC and signal integrity are derived from the results obtained, thus, the evaluation board of the measurement and control systems is especially suitable for performing function in high definition array induction log (HDAIL).

This paper presents the principle and method of chip microcomputer radiated emission using a TEM cell. It gives the calculation formulas of equivalent radiated power in free space. It also gives the emission measurement result for the MCS-51 chip microcomputer development system in the frequency band 0.15 MHz-30 MHz and gives further explanations.

This paper briefly presents the electromagnetic radiated emission mechanism of a program control mini-switchboard and the principle method of measurement of radiated emission using a TEM cell. It gives the calculating formulas of the equivalent radiated power of the equipment under test (EUT) in free space. It also gives the emission measurement result of a CLT-8 program control mini-switchboard in the frequency band 0.15 MHz/spl sim/30 MHz and gives further analysis.