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The paper introduced composition and performances of tunneling equipments of coal drift in China, namely roadheader unit, continuous miner unit, digging-bolt unit and full-hydraulic jumbo unit, and analyzed applicable conditions and technology characteristics of the equipments. It indicated development trend of the tunneling equipments of coal drift in China, that is using parallel operation of tunneling and supporting to realize rapid tunneling operation line of digging-bolt unit, using whole section tunneling technology to improve tunneling efficiency, using advanced technologies of automation and informatization to realize unmanned operation.

The paper introduced a mathematical model of three-phase PWM rectifier, analyzed principle of fixed switching frequency control strategy,built control structure of PWM rectifier based on inner current loop and outer voltage loop the simulated the fixed switching frequency control strategy by use of Matlab. The simulation waves of voltage at DC side and current of AC side proved the finxed swithing frequency control strategy is feasible.Meanwhile,it analyzed influence of setting key parameters of PWM rectifier on harmonic content of input current at AC side,and gave a comparatively reasonable parameter of filter inductor.

In order to solve the problem of harmonic circulation current in paralleled inverters system,a method of restraining harmonic circulating current was proposed based on analysis of mathematic model of single inverter with harmonic disturbance and produced principle of harmonic circulating current in paralleled inverters system,in which dual-ring control mode of current and voltage was used for single inverter of paralleled inverters system and coupling inductances were added to output ends of inverters.The theoretical analysis and simulation result verified the validity of the method.

The Saint-Venant equations can be used to describe the confluence process of unsteady flows in open channels. In largescale hydrological simulation software, solving the numerical solution of the equations is the biggest bottleneck restricting the running time of the program. This paper analyzes the structure of the serial solving program and the hotspots of calculation, and explores the parallelism of the singe-step simulation loop calculation section and instruction arrangement in the calculation intensive program. A master slave asynchronous parallel scheme is designed for the heterogeneous manicure architecture of the SunwaytTaihuLight supercomputer. The solver is ported, paired and accelerated based on MPI and thread libraries. SIMD technology is used to vectorize the slavecore's calculation section, and doubts buffering strategies are used to optimize the communication process. The tests show that the performance of hot functions can be increased by more than 3 times on average compared with the computation before optimization. Within a million-unit scale, the speedup of parallel programs using manicure optimization can maintain growing linearly, which shows strong scalability in Sunway's multi-nodes. [ABSTRACT FROM AUTHOR]

Due to the great resistance to first-line drugs, XDR-TB and MDR-TB are often difficult to cure completely. Pretomanid, PA-824 is one of the preferred drugs evaluated in clinical trials for the treatment of drug-resistant Mycobacterium tuberculosis. By inhibiting cell wall formation and respiratory toxicity, Pretomanid shows significant bactericidal activity against both replicative and stationary Mycobacterium tuberculosis. This article explores the effects of PA-824 on releasing active nitrogen substances and producing strong oxidative and cytotoxicity to Mycobacterium tuberculosis, prolonging early bactericidal activity, reducing the speed of Mycobacterium tuberculosis load in patients' sputum, and causing controllable adverse reactions, and comprehensively understand the anti-tuberculosis mechanism of pretomanid, including inhibiting the development of drug resistance of Mycobacterium tuberculosis strains, shortening the duration of tuberculosis treatment, and so on. The combination of pretomanid PA-824, bedaquinoline and linezolid, which has synergistic or additive potential in killing bacteria and inhibiting drug resistance, is also described, and is expected to further improve current TB treatment outcomes. [ABSTRACT FROM AUTHOR]

This paper reviewed the taxonomy of switching fabrics, and introduced the single-stage, multi-stage and multiplane multi-stage switching fabrics studied widely nowadays from the aspects of the switching architecture, scheduling algorithms and QoS guarantee. It reviewed the key elements and results of these switching fabrics, and compared them on the aspects of the implementation complexity, scalability, throughput, QoS guarantee. It also presented some iisues to be addressed in the development of high-speed switching fabrics. The efforts made in this paper can provide the reference for studying the high-speed switching fabrics further. [ABSTRACT FROM AUTHOR]

In order to precaution known and unknown attack of RFID technology, this paper proposed multi-decision tree model based on the analysis of RFID security protocol to check the intrusion behavior. By the analysis of the multi-decision tree model, the model can find the relationship of different attack of RFID technology. And the model has the advantage of extensibility and high efficiency, which make the multi-decision tree model suitable for all practical application of RFID system. [ABSTRACT FROM AUTHOR]

The characteristics of entrepreneurial team and its effect on performance have attracted increasing attentions in the past years. At present, whether in domestic or abroad, it has not been fully accepted that the way the characteristics constitute entrepreneurial team would affect it. In the basis of the relevant literature, the present authors hence explore the relationships between readily heterogeneity and underlying category heterogeneity in entrepreneurial teams, its interaction process such as conflict, communication, cohesion, interpersonal trust, and interactive type, and the performance. In addition, they also discuss their effect on the performance and the tendency for the future study from the point of view of the external environment factors, powers and policy, and business sentiment atmosphere. [ABSTRACT FROM AUTHOR]

Objective: To better understand predictive factors and role of autologous hematopoietic stem cell transplantation (auto-HSCT)in the post-remission therapy for adult Ph-negative B-cell acute lymphoblastic leukemia (B-ALL)patients., Methods: Outcomes of 86 adult patients with B-ALL who received auto-HSCT in our center from January 1996 to February 2014 were retrospectively analyzed., Results: Overall survival (OS)and disease free survival (DFS)at 5 years for the cohort were (63.8 ± 5.6)% and (60.9 ± 5.6)%, respectively. The cumulative non-relapse mortality (NRM)and relapse at 5 years were (4.70 ± 0.05)% and (34.40 ± 0.31)%. For DFS, age ≥ 35 years, high lactate dehydrogenase at diagnosis, high initial WBC count, blast cell proportion ≥ 5% on 15th day of the first induction therapy, complete remession (CR)1 to HSCT interval >6 months and CD34⁺ cells in graft ≥ 3.8 × 10⁶/kg were the poor prognostic factors. CR1 to HSCT interval >6 months was the independently undesirable factors in COX regression model. For 34 patients who had results of minimal residual disease (MRD), positive pretransplantation MRD (MRD≥0.01%), positive post-induction MRD or MRD positive again during the chemotherapy indicated poor prognosis, and the last one was the independent adverse prognostic factor., Conclusion: Auto-HSCT combined with post-transplantation maintenance chemotherapy could be an optional approach for adult B-ALL patients. MRD plays a significant role in the treatment choice for adult Ph-negative B-ALL patients.