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

An open reading frame upstream from the nifH gene of Klebsiella pneumoniae

An open reading frame upstream from nifHDK operon of Klebsiella pneumoniae had been described. The orientation of this open reading frame is opposite to that of nifHDK and sequence homology was found between the open reading frame promoter and the promoter of nifHDK operon. A recombinant plasmid carrying the promoter region of the open reading frame fused to the beta-galactosidase gene was constructed. Strains of E.coli were transformed with the plasmid containing this open reading frame promoter-lacZ fusion or co-transformed with it and a plasmid carrying the nifA gene. An appreciable activity of beta-galactosidase was found in strains which received both plasmids, indicating that the promoter of the open reading frame can be activated by the product of nifA gene. Thus, the open reading frame found between nifHDK operon and nifJ behaves just like other nif genes of K.pneumoniae in requiring the product of nifA as the positive effector for expression

Joint Rate Control and Demand Balancing for Electric Vehicle Charging

Charging stations have become indispensable infrastructure to support the rapid proliferation of electric vehicles (EVs). The operational scheme of charging stations is crucial to satisfy the stability of the power grid and the quality of service (QoS) to EV users. Most existing schemes target either of the two major operations: charging rate control and demand balancing. This partial focus overlooks the coupling relation between the two operations and thus causes the degradation on the grid stability or customer QoS. A thoughtful scheme should manage both operations together. A big challenge to design such a scheme is the aggregated uncertainty caused by their coupling relation. This uncertainty accumulates from three aspects: the renewable generators co-located with charging stations, the power load of other (or non-EV) consumers, and the charging demand arriving in the future. To handle this aggregated uncertainty, we propose a stochastic optimization based operational scheme. The scheme jointly manages charging rate control and demand balancing to satisfy both the grid stability and user QoS. Further, our scheme consists of two algorithms that we design for managing the two operations respectively. An appealing feature of our algorithms is that they have robust performance guarantees in terms of the prediction errors on these three aspects. Simulation results demonstrate the efficacy of the proposed operational scheme and also validate our theoretical results

Experimental Fire Studies on Load Bearing Steel Structures with Common Protective Coatings Used in China

Steel structures take the advantages of good stability, good ductility, low construction cost, fast construction and hence high flexibility in shape with high utilization rate. With the rapid economic growth, steel structures are popularly used in modern architecture, particularly in supertall buildings of height over 300 m in China. However, the fire behaviour of steel structures should be watched because the mechanical strength of steel reduces when temperature increases. In this paper, fire protective coatings commonly used in China for steel structures were studied by full-scale fire tests. Three types of ultra-thin, one type of thin and one type of thick coatings were evaluated. Test samples were prepared by applying the coatings on the typical H-type steel load bearing beams following standard fire resistance test. Different sets of fire protective coatings were applied on the surface of the sample as in the actual construction process. The coating thickness for the steel structural members met the Chinese regulation with ultra-thin fire protective coating of 2.00 mm ± 0.02 mm, thin fire protective coating of 5.0 mm ± 0.5 mm and thick fire protective coating of 25 mm ± 2 mm. Experiments were carried out in the large-scale testing facilities at Sichuan Fire Research Institute, Dujiangyan, Sichuan, China. The transient temperatures at different positions inside and outside the steel structure, and structural distortion of the steel structural members with different fire protective coatings under the testing condition were measured. Results on the measured temperatures, middle flexibility change values and corresponding time parameters on related parts of the test samples were then studied. A mathematical model was used for analyzing the result. The associated variables and correlation expressions among different variables were studied. Results can be taken as a reference for drafting new standards on evaluating the fire protective coatings for load bearing steel structures. For example, for the fire test of ultra-thin fire protective coating, it is possible to analyze and generalize the acquired data on temperature-time curve. For the thick-type steel structure fire protective coating, when the maximum temperature of the steel structure approaches 500oC and there is a high rate of temperature change, the fire resistance period of the structural members with protective coating can be predicted

EFFECT OF SQUAT DEPTH ON VERTICAL COUNTER-MOVEMENT JUMP HEIGHT – A PILOT INVESTIGATION

The purpose of this study was to investigate whether a deep squat depth can improve vertical counter-movement jump height as predicted by theoretical models after a training period for neuromusclar adaptation. Five male subjects peformed a baseline test of vertical counter-movement jump performance using their normal and a deeper squat depths. Jump height was measured by the centre of mass displacement using a motion capture system. After that, they underwent three weeks of daily training (2 sets of 10 deep jumps) before returning for a post-test. Overall, subjects jumped higher in the deep compared with the normal positions on both days (pre-test: normal=52.8 cm, deep=55.5 cm; post-test: normal=55.8 cm, deep=58.3 cm). There were, however, large variations in individual response to training and squath depth

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

Large Language Models Can be Lazy Learners: Analyze Shortcuts in In-Context Learning

Large language models (LLMs) have recently shown great potential for in-context learning, where LLMs learn a new task simply by conditioning on a few input-label pairs (prompts). Despite their potential, our understanding of the factors influencing end-task performance and the robustness of in-context learning remains limited. This paper aims to bridge this knowledge gap by investigating the reliance of LLMs on shortcuts or spurious correlations within prompts. Through comprehensive experiments on classification and extraction tasks, we reveal that LLMs are "lazy learners" that tend to exploit shortcuts in prompts for downstream tasks. Additionally, we uncover a surprising finding that larger models are more likely to utilize shortcuts in prompts during inference. Our findings provide a new perspective on evaluating robustness in in-context learning and pose new challenges for detecting and mitigating the use of shortcuts in prompts