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Based on the composite shaft lining structure, the research on the electromagnetic and negative pressure coupling adsorption technology of wall–climbing robots is of great significance to improve the level of safety monitoring during the construction and service of coal mine shafts. On the basis of theoretical research and computational data, the numerical simulation and simulation experiments of the coupled adsorption system of a wall–climbing robot are conducted in this research. In the ANSA software environment, of experimental models and experimental environments of electromagnetic and negative pressure adsorption devices are constructed to investigate, parameters such as air flow and the law behavior of fan pressure under different system conditions, including negative pressure and varying fan speeds. The intensity distribution of the magnetic flux inside the electromagnetic circuit under different working conditions and the law of change in the direction of movement are explored. Furthermore, the power consumption and power increment of the electromagnetic and negative pressure adsorption system under the same adsorption force output are compared and analyzed. Based on the experimental results, a series of conclusions are verified; firstly the negative pressure of the system should be formed under certain basic specific fundamental conditions; secondly, the main velocity of the negative pressure adsorption system and the full pressure of the fan are determined by the internal and external pressure difference and the fan speed, respectively; lastly, the adsorption efficiency of electromagnetic adsorption is significantly higher than that of negative pressure adsorption. These research findings are expected to introduce a new technical means approach for the safety monitoring of vertical shafts and shafts in coal mines, thereby demonstrating the theoretical significance and practical value of the application and development of an underground multi–scenario robot automation system in coal mines.

Mountain Wumingshan (Mt. WMS) is located in the southeastern foot of the Tibet Plateau with an altitude of 4,800 m. It is one of the candidate sites to place China’s next-generation large-scale solar telescope. A temporary observation platform has been built at Mt. WMS, but there is still a great need of a stable solar-seeing monitoring for long-term observations. Based on the preliminary studies on the Solar Differential Image Motion Monitor (SDIMM) of the Yunnan Observatories, we built an improved version of this early prototype, which is called Wumingshan Mountain Automated Solar Differential Image Motion Monitor (WMA-SDIMM). We develop the automatic system of the WMA-SDIMM, investigate the reliability and precision of our measurements by error analysis and comparison testing, and present the statistical results from October 2016 to September 2017 at Mt. WMS. WMA-SDIMM works very well at Mt. WMS and is quite suitable for long-period daytime seeing observations.

We present a new sub-class of type III solar radio burst at the high frequencies around 6.0 GHz. In addition to a descending and an ascending branch on the dynamic spectrum, it has an inverted morphology different from the simple type U-burst. We call it "partial N-burst" because it is interpreted as the known N-burst minus its first branch. The partial N-burst presented here was detected among a reverse slope type III (RS-III) burst group prior to the type V solar radio continuum and was simultaneously recorded by two spectrometers at the National Astronomical Observatories, Chinese Academy of Sciences (NAOC, 5.20-7.60 GHz) and at Purple Mountain Observatory (PMO, 4.50-7.50 GHz) on 1999 August 25. After the N-burst and M-burst, the partial N-burst is a third piece of evidence for a magnetic mirror effect in solar radio observation, when the same electron is reflected at a pinched foot of a flare loop.

A broadband solar radio spectrometer with a bandwidth of about 7 GHz has been developed in China for solar maximum 23. This work is a cooperative project of Beijing Astronomical Observatory (BAO), Purple Mountain Observatory (PMO), Yunnan Observatory (YNO), and Nanjing University. The spectrometer of PMO worked in the waveband of 4.5-7.5 GHz, that of BAO in 1-2 GHz,2.6-3.8 GHz, and 5.2-7.6 GHz, and that of YNO in 0.7-1.5 GHz. The spectrometer of PMO is a multichannel and frequency-agile one with a time resolution of 1-5 ms and a frequency resolution of 10 MHz. It started to operate in August 1999 and since then more than 300 spectral events have been observed, and some type III or type III-like structures have also been found. In this paper, some selected typical events, for example, the events on 25 August 1999 and 27 October 1999, are presented, and some new observed features are also described and discussed.

A new instrument of broadband solar radio spectrometer working at waveband 4.5-7.5 GHz was developed at Purple Mountain Observatory for Solar Maximum 23. Some new results of spectral observation have been obtained since August 1999. Two typical type III mu bursts with rich fine structures are presented and some interesting features discussed.

COPY THE ORIGINAL Analysis of the total eclipse observation of 1997 March 9 at wavelength 8.6 mm, shows that, at this wavelength, the solar radius is 1.012 R., the total flux density is 2540 sfu, the mean brightness temperature of the solar disk is 9632 K, and the brightness temperature distribution shows limb brightening at the inner edge of the solar disk, the average brightness at 0.936-0.992 R. being 9.7% above the central brightness.

In this paper we have analyzed the characteristics of both periodic pulsation and absorption before two impulsive events at 1.35 cm observed with a radio telescope (aperture 13.7 m) with a spatial resolution ∼ 4 arcmin and a high sensitivity of 0.004sfu. It is shown that the observed characteristics can be interpreted by local heating of the source region.

The statistical analysis of the appropriate physical parameters of solar soft X-ray (SXR) flares and microwave bursts originating in four larger active regions (Boulder Nos. 5395, 5629, 5669 and 5680) in 1989 shows that their correlation coefficient R reach 0.9≤R1. This fact indicates that there is a close association between SXR flares and microwave bursts.Such result can be interpreted by the physical process that a strong enough nonthermal electron beam injected downward from the microwave source (at the top of a flare loop) into the chromosphere is able to cause the chromospheric evaporation due to collision heating, the evaporated chromospheric plasma with superhot temperature Te(≈107K) moves upwards along the flare loop and emits SXR radiation. As the flare loop is filled with superhot plasma, the SXR emission reaches the peak flux. Thus the peak flux of SXR emission appears often later than that of microwave burst.