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A traditional distance protection relay uses a lumped parameter model of the transmission line. For a long 1000-kV UHV line with large distributed capacitance, such a simplified line model is inadequate and can cause malfunction of the relay due to large errors in the impedance measurement. This paper presents a new line model for a distance relay and the procedure of reliable fault impedance measurement and relay setting. It describes the proposed application of the relay developed to a 645-km 1000-kV UHV transmission line including shunt reactor compensation, which is currently being constructed in China. Tests are carried out on an RTDS (real time dynamic system) to evaluate the relay performance, showing significant improvement compared to a more traditional distance relay. The new distance relay is shown to satisfy the requirement of 1000-kV UHV transmission line protection. [ABSTRACT FROM AUTHOR]

As the conventional mho relay usually takes the bus voltage as a polarizing voltage, its operating characteristic is fixed and cannot adapt to fault resistance. To enhance the capability against fault resistance, based on the compensated voltage changing with fault resistance, a kind of adaptive impedance relay with composite polarizing voltage is presented in this paper. On the other hand, the operating boundary of the adaptive relay may enter into an "inphase" area along with the increase of fault resistance. To prevent the adaptive relay from maloperation in the "inphase" area, a new additional blocking component is also proposed. Both the adaptive relay and the blocking component were all analyzed in the voltage plane and the impedance plane. Theoretical analyses show that both of them have circular characteristics with greater resistive tolerance. The performance of the relay has been demonstrated on a two-source 500-km line 750-kV system. [ABSTRACT FROM AUTHOR]

In order to accurately measure the impedance, the residual current for impedance measurement in ground distance relay is compensated in a fixed manner. It has been shown that the above compensation manner may have negative impact on the phase selection in mho elements in a single-pole trip scheme. A new residual current compensation method based on the magnitude of current of each phase for mho elements is presented in this paper. The performance of this new method is analyzed under all kinds of fault conditions. Simulation studies are carried out to investigate the new compensation method based fault component impedance relay in a typical transmission system. The relay has shown satisfactory performances under various fault conditions especially for the close-in ground fault and cross-country fault. This new compensation method can also be used in phase selector based on impedance measurement. [ABSTRACT FROM PUBLISHER]

The article focuses on traditional medicine use in dentistry, dental education, orthodontics products in China. It notes that Chinese herbal medicines are included in tooth paste. It cites that Chinese schools are composed of four departments including endodontic dentistry, oral surgery and oral pathology, prosthetics, and orthodontics. It cites several Chinese products including direct bonding agent, NiTi archwire and pre-adjusted appliance. Problems of Chinese orthodontics are also discussed.

The MRL-lpr/lpr and MRL-++ mice were studied for the expression of cytokines in the spleen, lymph node, thymus, kidney and brain through the reverse transcription-polymerase chain reaction (RT-PCR). The frequencies of IL-4 and TNF-α expression in the thymus and spleen were significantly higher in MRL-lpr/lpr mice than in MRL-++ mice from the age of 17 to 32 weeks. More importantly, IL-4 transcript was demonstrated in the early rather than in the terminal stage of the lupus disease. At the 20th week, MRL-lpr/lpr mice with active disease exhibited higher concentrations of IL-1α, IL-6 and TNF-α in serum than MRL-++ mice. Interestingly, in MRL-lpr/lpr but not MRL-++ mice, the IL-6 concentration in culture supernatants of the thymic cells was significantly higher than that of the splenic or lymph node cells. On the other hand, IL-6 and IL-1β were expressed in the brain and kidney of MRL-lpr/lpr mice but not of MRL-++ mice. Cultured MRL-lpr/lpr mesangial cells could also express IL-6 but to a lesser extent. These results suggest that the abnormal splenic and thymic IL-4 and TNF-α expression may predispose the development of autoimmune reactions. The expression of IL-1β and IL-6 in the brain and kidney may be implicated in the damage of these two organs in MRL-lpr/lpr mice. [ABSTRACT FROM AUTHOR]

A 25-year-old man presented with several prominent subcutaneous masses in the occipital region of the scalp. He had a long history of tinea capitis and tinea corporis infection. Histopathology of the occipital lesions showed mycelial aggregates in the deep dermis and subcutis. Cultures of the excised material and superficial scales grew a fungus identified as Microsporum ferrugineum. We propose the term ‘dermatophyte pseudomycetoma’ to describe this distinctive mycosis. [ABSTRACT FROM AUTHOR]

The article presents a case study of 41-year-old woman, who suffered from haemoptysis and was referred to a chest surgeon because of an abnormal chest radiograph. The woman had poliomyelitis during her childhood and underwent caesarean sections, but no history of dysmenorrhoeal or abnormal vaginal bleeding. Physical examinations and laboratory investigations were unremarkable and she received hormonal therapy.

The article describes the case of a 49-year-old female patient with a right invasive ductal breast cancer which has metastasized to the lymph nodes.

Static analysis is performed for fiber windings to quantitatively control the radial stress at the outer radius of the piezoelectric ceramic tube. The radial stress is verified both experimentally and theoretically, and the dependence of the resonant and material properties of the piezoelectric ceramic tubes on the radial stress is clarified. The resonance frequencies and dielectric loss remain relatively stable, but the relative permittivity and the short circuit elastic constant decrease with the radial stress. The variations of the increased bandwidth and decreased electromechanical coupling coefficient (k31), piezoelectric constant (d31 and g31), and mechanical quality factor (Qm) are associated with the height-to-radius ratio. The properties of three cylindrical transducers applied with various radial stress show similar change tendencies, and a difference of 0.34 MPa radial stress results in a variation of approximately 1 3 in the bandwidth, 1 4 in Qm, 1 5 in k31, d31, and g31, and 1 6 in the amplitude of the first pulse. These results suggest that the consistency of the radial stress is essential, and it should be relatively small. These findings guide the design and preparation of the enhanced transducer. [ABSTRACT FROM AUTHOR]