Estimate black hole masses of AGNs using ultraviolet emission line properties

Based on the measured sizes of broad line region of the reverberation-mapping AGN sample, two new empirical relations are introduced to estimate the central black hole masses of radio-loud high-redshift ($z > 0.5$) AGNs. First, using the archival $IUE/HST$ spectroscopy data at UV band for the reverberation-mapping objects, we obtained two new empirical relations between the BLR size and \Mg/\C emission line luminosity. Secondly, using the newly determined black hole masses of the reverberation-mapping sample for calibration, two new relationships for determination of black hole mass with the full width of half maximum and the luminosity of \Mg/\C line are also found. We then apply the relations to estimate the black hole masses of AGNs in Large Bright Quasar Surveyq and a sample of radio-loud quasars. For the objects with small radio-loudness, the black hole mass estimated using the R_{\rm BLR} - L_{\eMg/\eC} relation is consistent with that from the $R_{BLR} - L_{3000\AA/1350 \AA}$ relation. But for radio-loud AGNs, the mass estimated from the R_{BLR} - L_{\eMg/\eC} relation is systematically lower than that from the continuum luminosity $L_{3000\AA/1350\AA}$. Because jets could have significant contributions to the UV/optical continuum luminosity of radio-loud AGNs, we emphasized again that for radio-loud AGNs, the emission line luminosity may be a better tracer of the ionizing luminosity than the continuum luminosity, so that the relations between the BLR size and UV emission line luminosity should be used to estimate the black hole masses of high redshift radio-loud AGNs.Comment: 19 pages, 10 figure

A22: Investigation on the Status Quo of Extracurricular Sports Activities in Primary and Secondary Schools of Yan \u27An City Before and After COVID-19

Purpose: Since the outbreak of the Novel coronavirus pneumonia (COVID-19) in December 2019, the General Office of the National Health Commission has put forward the epidemic prevention requirements, such as minimizing unnecessary travel. In December 2022, The State Council issued the latest epidemic prevention policy, marking the country\u27s three-year epidemic control policy. In this case, this paper conducted a comparative study on the number of participants, cognition, attitude, motivation, frequency, time and organization of extracurricular sports activities in primary and secondary schools of Yan \u27an City before and after the COVID-19 outbreak, and analyzed and studied the data obtained. Methods: By consulting relevant information; Conduct targeted interviews with leaders involved in the organization and management of extracurricular sports activities and teachers of related majors; Questionnaires were formulated and distributed, and data of the questionnaires were statistically processed to conduct a comparative study on the status quo before and after the epidemic. 400 students from Yuying Middle School, Yan \u27an Middle School, Yan \u27an No. 3 Middle School, Yan \u27an Vocational and Technical College Affiliated Primary School, Yan \u27an New District No. 2 Middle School and Beiguan Primary School were selected as the research objects. According to the research needs, a total of 400 questionnaires were sent out and 392 were recovered with a recovery rate of 98%, among which 386 were valid with a recovery rate of 96.5%. The collected questionnaires can meet the needs of this survey. The questionnaire mainly includes the following questions: the form of PE teaching for PE teachers. Students\u27 attitude, liking, motivation and favorite sports to participate in extracurricular sports activities. How often and how long students participate in extracurricular sports activities each week, and how the school conducts extracurricular sports activities. Results: According to the survey, 62.4% of primary and secondary school students think it is important to take part in extracurricular sports activities; The number of people who like extracurricular sports activities reached 145, accounting for 37.4% of the total, among which 115 were boys. The motivation of primary and middle school students to participate in extracurricular sports activities ranked first: promoting physical and mental health, accounting for 45%; 22.2%, 20.4%, 19.4% and 17.8% of the participants chose Taekwondo, roller skating, football and basketball, while 8.2% and 8.8% of the participants chose Wushu and volleyball. The frequency of participating in extracurricular sports activities is seven to ten times a week, accounting for 32.2% of the total; The number of male students who spend 60-90 minutes on each activity is the largest, accounting for 32.3%, while the number of female students who spend less than 30 minutes on each activity is the largest, accounting for 39.7%. Among primary and middle school students, the main ways to participate in extracurricular sports activities are morning exercise, recess exercise and club activities, accounting for 79%, 79.8% and 49.7% respectively. The quality of school organization directly affects students\u27 interest. During the epidemic, 46.32% of physical education teachers chose to provide students with online physical education courses, 20.18% chose video classes, and only 9.34% chose live classes. Conclusion: With the end of the epidemic, although extracurricular sports activities did not return to the pre-epidemic level, students\u27 attitude, cognition, motivation, and other subjective factors have significantly improved, and they pay more attention to physical health

Effect of Grazing on Soil Carbon and Nitrogen in Alpine Madow, Eastern of Tibetan Plateau

As the grassland ecosystem in the Tibetan Plateau is very fragile, overgrazing likely leads to more serious damages to it than other ecosystems. In the past 30 years, 37% of the alpine meadows have been heavily damaged by grazing causing degradation of native vegetation, a decline in species richness and feed value, and more seriously soil erosion (Six et al. 2004). The impact of grazing on alpine grasslands appears to be hysteresis, as the soil needs more time to recover than the vegetation. So analysing the effect of grazing intensity on soil characteristics is an important way to reveal how grazing influenced grassland ecosystem. Although much research about grazing effects on nutrients, immobilization of carbon (C) and nitrogen (N) in soils and soil microbes have been done in different terrestrial environments, similar effort has rarely focused on the Tibetan Plateau. In this study, soil organic carbon (SOC) and total nitrogen (STN) in 0-30 cm soil depth were measured in the alpine meadow at the northeastern margin of the Tibetan Plateau, to determine suitable grazing intensity from the viewpoints of soil health and fertility, and providing a scientific basis for guiding the reasonable use of the alpine meadow

High-resolution modeling of typhoon morakot (2009): Vortex rossby waves and their role in extreme precipitation over Taiwan

A high-resolution nonhydrostatic numerical model, the Advanced Regional Prediction System (ARPS), was used to simulate Typhoon Morakot (2009) as it made landfall over Taiwan, producing record rainfall totals. In particular, the mesoscale structure of the typhoon was investigated, emphasizing its associated deep convection, the development of inner rainbands near the center, and the resultant intense rainfall over western Taiwan. Simulations at 15- and 3-km grid spacing revealed that, following the decay of the initial inner eyewall, a new, much larger eyewall developed as the typhoon made landfall over Taiwan. Relatively large-amplitude wave structures developed in the outer eyewall and are identified as vortex Rossby waves (VRWs), based on the wave characteristics and their similarity to VRWs identified in previous studies. Moderate to strong vertical shear over the typhoon system produced a persistent wavenumber-1 (WN1) asymmetric structure during the landfall period, with upward motion and deep convection in the downshear and downshear-left sides, consistent with earlier studies. This strong asymmetry masks the effects of WN1 VRWs. WN2 and WN3 VRWs apparently are associated with the development of deep convective bands in Morakot's southwestern quadrant. This occurs as the waves move cyclonically into the downshear side of the cyclone. Although the typhoon track and topographic enhancement contribute most to the recordbreaking rainfall totals, the location of the convective bands, and their interaction with the mountainous terrain of Taiwan, also affect the rainfall distribution. Quantitatively, the 3-km ARPS rainfall forecasts are superior to those obtained from coarser-resolution models. © 2013 American Meteorological Society

The black hole fundamental plane from a uniform sample of radio and X-ray emitting broad line AGNs

We derived the black hole fundamental plane relationship among the 1.4GHz radio luminosity (L_r), 0.1-2.4keV X-ray luminosity (L_X), and black hole mass (M) from a uniform broad line SDSS AGN sample including both radio loud and radio quiet X-ray emitting sources. We found in our sample that the fundamental plane relation has a very weak dependence on the black hole mass, and a tight correlation also exists between the Eddington luminosity scaled X-ray and radio luminosities for the radio quiet subsample. Additionally, we noticed that the radio quiet and radio loud AGNs have different power-law slopes in the radio--X-ray non-linear relationship. The radio loud sample displays a slope of 1.39, which seems consistent with the jet dominated X-ray model. However, it may also be partly due to the relativistic beaming effect. For radio quiet sample the slope of the radio--X-ray relationship is about 0.85, which is possibly consistent with the theoretical prediction from the accretion flow dominated X-ray model. We briefly discuss the reason why our derived relationship is different from some previous works and expect the future spectral studies in radio and X-ray bands on individual sources in our sample to confirm our result.Comment: 23 pages, 7 figures, ApJ accepte

Landing dynamic simulation of aircraft landing gear with multi-struts

The landing dynamic modeling technology for aircraft landing gear is based on accurate evaluation of the landing gear landing performance. Aiming to study the post landing gear, a model for dynamic analysis of the gear is established based on the analysis of the structure mechanical features and the characteristics of landing dynamic performance. The landing dynamic analysis of strut landing gear is conducted by using LMS Motion software. According to the comparative analysis between simulation and drop test, the dynamic modeling method is accurate and reasonable. To obtain the load distribution of each landing gear, a full aircraft model of multi-strut landing gear is built, and then the dynamic simulation analysis is carried out in different landing process. The study shows that the rear main landing gear bears the highest proportion of load. The initial pitch angle influences load distribution of each landing gear. A lateral force is exerted on the main landing gear tire, when the plane is landing asymmetrically. With landing condition becoming stable, the lateral force is eliminated