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Slide drilling is widely used in directional drilling because of its lower cost, but the tool-face adjustment during the drilling process is almost completed by the driller, and the automatic control has not yet been realized. The main difficulty is that the drill string system has a large amount of contact and friction with the wellbore. Moreover, it is also affected by the viscous force of the mud fluid, which brings more difficulty to achieve accurate dynamic model. Considering that the actual drilling is too costly, it is necessary to establish an indoor experimental system to simulate the response of the slide drilling tool-face, thus providing an experimental platform for the research of the control method. In this paper, the dynamic equation of the torsion process of the drill pipe is established. According to the model similarity theory, the similarity condition of parameters and scale correspondence between the experimental model and the drilling prototype are obtained, which provides the basis for selection of simulated drill pipe and mud. Then the expert PID method is used to realize the automatic tool-face control based on the laboratory experimental system. The experimental results show that the expert PID method can obtain better control effect rather than the traditional PID method, and it could be used in the actual slide drilling because of the dynamic similarity.

Objective: To investigate the immune regulation of "nourishing Yin and Qi, activating blood circulation and detoxifying" in elderly diabetic patients complicated with acute coronary syndrome (ACS), and analyze its possible mechanisms. Methods: 69 diabetic patients aged 50-75 years and complicated with ACS, from March 2019 to February 2020 in the Department of Cardiology and Traditional Chinese medicine (TCM) in the Affiliated Hospital of Youjiang Medical University for Nationalities were randomly divided into control group (34 cases) and treatment group (35 cases). The control group was given western medicine standardized treatment, while the treatment group were treated with HJJR on the basis of routine Western medical treatment, and the therapeutic course for al1 were 2 months. Before and after treating, in the two groups, the levels of pro-inflammatory factors [C-reactive protein (CRP), interleukin-8 (IL-8), tumor necrosis factor - α (TNF - α) and anti-inflammatory factors [IL-10, adiponectin (ADPN)] were detected. The clinical symptoms of chest tightness, chest pain, attacking frequency and duration, palpitation, shortness of breath, fatigue and the total scores of syndromes in the two groups were detected. At the same time, electrocardiogram (ECG) changes and adverse reactions were observed. Results: Compared with before treatment, after treating, the levels of pro-inflammatory factors CRP, IL-8, TNF - α in the two groups were evidently decreased, while the anti-inflammatory factors IL-10 and ADPN were obviously increased, but the changes in the treatment group were more significant (all P

In this study, a novel CRF01_AE/07_BC HIV-1 recombinant form, with five breakpoints in the pol, vpr, env, and nef gene regions, was identified from a voluntary blood donor in North China. Our study showed that this HIV-1 recombinant form might be a second-generation recombinant form from two predominant strains in the men who have sex with men (MSM) population, with the CRF07_BC fragments belonging to a CRF07_BC lineage specific to Chinese MSM and the CRF01_AE fragments belonging to the CRF01_AE lineage 5 common among MSM in northern China. Our findings supported the high-risk blood donation behaviors of MSM, implied the increasing complexity of the HIV-1 epidemic among the Chinese MSM population, and called more attention to the effectiveness of the screening test for the growing number of new HIV-1 recombinant forms.

A new unknown horizontal line Mura which happened in a new product development has been studied.Through analysis and improvement study,it was found that Fan-out area Gate-Line metal resistance difference of different layer in alternate layout design is the main reason for this unknown Mura defect.The experimental results show that this defect can be solved by changing the material and thickness of Gate-Line layer,and the feasibility of mass production was demonstrated through experimentation.

HIV prevalence is still rapidly increasing among Chinese men who have sex with men (MSM). The Internet also makes it easier for MSM to have casual partners. This study aims to evaluate the trend of Internet-based sex-seeking behavior of MSM and its impact on HIV prevalence, the distribution of HIV subtype strains, and transmitted drug resistance rates. A serial cross-sectional study was conducted from 2009 to 2014. Of the 1,981 MSM, 50.5% (1,000/1,981) mainly sought homosexual partners through the Internet (Internet-based MSM, IBM). The proportion of IBM among total MSM subjects increased from 43.3% to 61.5% (p<0.001). HIV prevalence of IBM increased from 5.7% to 20.7%, while that of non-Internet-based MSM (NIBM) increased from 7.0% to 14.7%. A relative higher proportion of NIBM were infected with HIV CRF01_AE subtype than IBM (79.5% versus 72.2%, p=0.52). Multivariable analysis found IBM had a significantly higher HIV prevalence than NIBM (13.2% versus 10.5%, aOR = 1.4, 95% CI [1.0–1.9]). Being a migrant non-Shenyang resident MSM (aOR = 1.9, 95% CI [1.3–2.9]) and occasionally/never using condoms with casual homosexual partners (aOR = 1.7, 95% CI [1.1–2.6]) were two distinct risk factors for HIV infection in IBM. More efforts should be targeted towards developing interventions aimed at IBM, particularly migrant MSM and who engage in UAI with casual homosexual partners.

Yu Yonghui, Qiu Haixiong, and Cui Qiang tell the story of one typical Guangdong industrial cluster and the role of a government-initiated and -funded Innovation Center in balancing central policy. Local officials, the local merchant association, and local universities helped to give Guangdong private firms the information, knowledge, and ability to buy modern equipment that they needed in order to be able to manufacture products for the world market.

Intelligent ventilation bed is a new-style mechanical ventilation equipment, whose core is the movement system of the bed's abdomen- splint. In order to realize the control function synchronized with breath stably, the mathematical model of abdomen -splint is set up and fuzzy self-adaptive PID controller is designed. The parameters of the controller are dynamically adjusted with error and error changing rate. So the control performance can be satisfied momentarily. Simulation results show that using fuzzy PID controller can improve the dynamic performance and enhance the anti-jamming ability through the comparison of the traditional PID controller. At the same time, experimental results demonstrate that fuzzy self-adaptive PID controller has smaller overshoot, shorter response time. Moreover, the control precision is well, and its robustness and stability are obviously better than traditional PID.

Introduction Tetanus is a fatal infectious disease. It could cause typical signs like pain, headache, stiffness, and spasms of facial muscles as well as trunk and skeletal muscles. The symptoms are risus sardonicus, trismus and opisthotonus. How to control the spasticity and rigidity of muscles is still a problem. Our object is to raise the feasibility of titration of high dose sedatives in the management of severe tetanus. Case presentation A 37-year-old woman was sustained a 2 cm wound in the right anterior part of chest. Then she developed progressive risus sardonicus, trismus and opisthotonus, elevated liver enzymes, creatine kinase, lactic acid and myoglobin. The patient was treated with continuous infusion of propofol (50-100 mg/h, 22 days) and midazolam (5-20 mg/h, 37 days) for sedation, vecuronium (1-6 mg/h, 25 days) for muscle relaxation. The symptoms of tetanus were controlled, and there were no side-effects appeared. Conclusion We report one case of severe tetanus. In this case, several types of sedative were administrated and most of them were high doses. The patient recovered while no complications remained. This case report indicated that combination and high dose of sedation for severe tetanus were feasible. We recommend this treatment as the guidance of similar patients.

This paper introduces the 1:12 model test of the feed support system of a 500-meter aperture radio telescope. The main purpose of this research is to study the controllability and performance of a cable-driven Gough-Stewart platform used as a positioning platform for the feed of a large radio telescope. The Gough-Stewart platform is used for vibration control, the upper platform of which is driven by long cables and the lower one is to be stabilized in tracing the observation trajectories. The similarity for the scaled model and the implementation are illustrated. The test study has been carried out in two steps. The first step involves the uncoupled cable-car tracking control tests and the Gough-Stewart platform vibration suppression tests, while the second step carries out the coupled test of the system. The general aspects of the control system and control law are introduced and the problems arising in the tests are also addressed. Results on the 50m×50m×12m are also presented.

Fourier Transform Infrared gas analyzers have been widely used for speedy quantitative analyses of gases, and it is found that in many cases field maintainability determines the instruments’ online applicability instead of the instrument’s accuracy as is desired. To be maintenance-free is both the target of online instruments and the key to their field applications. Analyses show that if a background can be collected simultaneously with the sample spectrum, the transmittance will be only a function of concentration. Gas spectra collected on Nicolet670 of attenuated inputs and adjusted gains are examined via OMNIC software. Collected data exhibit that the absorbance spectra keep constant when input energy increases 8 times and the instrument gains becomes to 2.0 and 4.0 times. On viewing the absorption peaks vary with wavenumber in high “frequency” and that of the spectrometer itself in low frequency, by subtracting its instrumental response function of a transmittance spectrum extracted by wavelet transform, an absorbance spectrum of air is obtained and comparisons demonstrate that it is a summation of absorbance of the sample and that of gases in the optical path of the spectrometer. Calibration-free and background-free principles are thus exhibited and they construct maintenance-free principles of FTIR gas analyzers.

Spectral estimation has been applied broadly in the signal-processing domain. In modern spectral estimation methods, the model parameters will be obtained by solving the Yule-Walker equations. There are several common disadvantages such as complicated processing steps and heavy calculation load in all the optimized algorithms. In this paper, two methods using neural networks are discussed. In the first one, the solving of the equations set is avoided. In the second one, the solving of the equations set is simplified by using a simple BP neural network. Simulations show that the spectral analysis effect is better than some other methods.

Seabed acoustic parameters are very important to underwater acoustic field prediction in shallow water. The existing inversion methods generally uses a vertical line array to receive the signal and its platform is stationary, which can not be operated for a large area with high resolution. The methods for extracting seabed reflection losses based on three kinds of line arrays were studied. A fast inversion scheme for the seabed acoustic parameters was presented, which uses a towed tilted line array and three acoustic sources to cover a large scope of grazing angles. The error analysis was made for this method. The simulation results show that different arrays require different experimental configurations to cover the same scope of grazing angles. The vertical line array must operate with several acoustic sources and require a stationary platform of the array. The towed horizontal line array needs only one acoustic source but requires a large-aperture line array. The towed tilted line array combines the merits of the vertical line array and the horizontal line array, which can inverse the seabed acoustic parameters in a moving and high resolution way and requires only a line array of smaller aperture.