Studies on the equatorial spot of G-type contact binary UV Lyn

New CCD photometric observations of G-type contact binary UV Lyn were obtained in 2006 and 2020, when the light curves (LCs) show positive O'Connell effect and negative O'Connell effect, especially. From the previous studies, the LCs by other ground-based telescope are variable from 1973 to 2020, particularly the magnitude difference between the two maxima. These phenomena indicate that the component is active in the past 47 years. In addition, under the monitoring of the space telescope of Transiting Exoplant Survey Satellite (TESS) from January to March in 2020, we fortunately find the continuous variations of O'Connell effect in every circle for the first time. The analysis also shows that in a short time, the positive O'Connell effect has been transformed into the negative one, which proves that there are stronger magnetic activities on the surface of the component. By using the Wilson-Devinney code with a spot model, these photometric solutions confirm UV Lyn is a shallow W-subtype contact binary with a cool equatorial spot on the less massive component. The successive variability of O'Connell effect possibly result from one equatorial cool spot shifting gradually along with time. We also investigate its \emph{O-C} curve from these continuous LCs, there is not obvious variation in such short time. while, the O’Connell effect as the indicator of the magnetic activity are possibly undergoing a periodic trend of a period of nearly 38 days. Comparing \emph{O-C} curve, we could find there is not relation between the period variation and magnetic activity.

Real-Time Traffic Flow Forecasting via a Novel Method Combining Periodic-Trend Decomposition

Accurate and timely traffic flow forecasting is a critical task of the intelligent transportation system (ITS). The predicted results offer the necessary information to support the decisions of administrators and travelers. To investigate trend and periodic characteristics of traffic flow and develop a more accurate prediction, a novel method combining periodic-trend decomposition (PTD) is proposed in this paper. This hybrid method is based on the principle of “decomposition first and forecasting last”. The well-designed PTD approach can decompose the original traffic flow into three components, including trend, periodicity, and remainder. The periodicity is a strict period function and predicted by cycling, while the trend and remainder are predicted by modelling. To demonstrate the universal applicability of the hybrid method, four prevalent models are separately combined with PTD to establish hybrid models. Traffic volume data are collected from the Minnesota Department of Transportation (Mn/DOT) and used to conduct experiments. Empirical results show that the mean absolute error (MAE), mean absolute percentage error (MAPE), and mean square error (MSE) of hybrid models are averagely reduced by 17%, 17%, and 29% more than individual models, respectively. In addition, the hybrid method is robust for a multi-step prediction. These findings indicate that the proposed method combining PTD is promising for traffic flow forecasting.

TraMoS

We present 22 new transit observations of the exoplanets WASP-18Ab, WASP-19b, and WASP-77Ab, from the Transit Monitoring in the South project. We simultaneously model our newly collected transit light curves with archival photometry and radial velocity data to obtain refined physical and orbital parameters. We include TESS light curves of the three exoplanets to perform an extended analysis of the variations in their transit mid-time (TTV) and to refine their planetary orbital ephemeris. We did not find significant TTVRMS variations larger than 47, 65, and 86 s for WASP-18Ab, WASP-19b, and WASP-77Ab, respectively. Dynamical simulations were carried out to constrain the masses of a possible perturber. The observed mean square (RMS) could be produced by a perturber body with an upper limit mass of 9, 2.5, 11 and 4 M⊕ in 1:2, 1:3, 2:1, and 3:1 resonances in the WASP-18Ab system. In the case of WASP-19b, companions with masses up to 0.26, 0.65, 1, and 2.8 M⊕, in 1:2, 2:1, 3:1, and 5:3 resonances respectively, produce the RMS. For the WASP-77Ab system, this RMS could be produced by a planet with mass in the range of 1.5−9 M⊕ in 1:2, 1:3, 2:1, 2:3, 3:1, 3:5, or 5:3 resonances. Comparing our results with RV variations, we discard massive companions with 350 M⊕ in 17:5 resonance for WASP-18Ab, 95 M⊕ in 4:1 resonance for WASP-19b, and 105 M⊕ in 5:2 resonance for WASP-77Ab. Finally, using a Lomb-Scargle period search we find no evidence of a periodic trend on our TTV data for the three exoplanets.

An Overview of Forest Offences in Himachal Pradesh from 1965-66 to 2009-10: Trends in Detection and Manner of Disposal

An exercise undertaken in this article has unravelled the status of forest offences in Himachal Pradesh from 1965-66 to 2009-10. It brought out that a total of 10,39,172 no. of forest offences (average 23093 annually) were taken cognizance of in the State from 1965-66 to 2009-10. The highest no.of offences ( 43901 no.) were detected in 1975-76 and the lowest (11869 no.) in the year 2006-07. Illegal felling & grazing related offences together constituted nearly 57%, forest fire related offences were less than 2% whereas the miscellaneous offences were nearly 40% of the total. The period from 1971 to 1985 experienced sharp increase in the number. of forest offences, though the offences taken cognizance of were disposed off quite efficiently. The rate of disposal ranged from 71.88% to 80.13% during various time periods from 1965-66 to 2009-10 with overall disposal rate of 77.52 % Of the total no. of offences disposed off 9.3% of the cases were taken to Courts/ authorised officers and 78.4%. were disposed off by way of compounding, 13.23% remained untraced/filed. Periodic trend (5 year blocks i.e. P1 to P9) revealed 50% decline in forest offences during P-9 (2005-2009) compared to what existed during P-1(1966-70). Ironically the downturn was despite tremendous increase in human and domestic animal population in the State during same time. The success rate of the offences decided by Courts/ Authorised officers ranged from 76.92% during-P-1(1965-69) to 98.9% during P-9(2005-09) as per data published by State Forest Department. On the other hand, cases registered with Police from 1988 to 2015 secured conviction rate of 12.99%.

Detecting space-time disease clusters with arbitrary shapes and sizes using a co-clustering approach

Ability to detect potential space-time clusters in spatio-temporal data on disease occurrences is necessary for conducting surveillance and implementing disease prevention policies. Most existing techniques use geometrically shaped (circular, elliptical or square) scanning windows to discover disease clusters. In certain situations, where the disease occurrences tend to cluster in very irregularly shaped areas, these algorithms are not feasible in practise for the detection of space-time clusters. To address this problem, a new algorithm is proposed, which uses a co-clustering strategy to detect prospective and retrospective space-time disease clusters with no restriction on shape and size. The proposed method detects space-time disease clusters by tracking the changes in space–time occurrence structure instead of an in-depth search over space. This method was utilised to detect potential clusters in the annual and monthly malaria data in Khyber Pakhtunkhwa Province, Pakistan from 2012 to 2016 visualising the results on a heat map. The results of the annual data analysis showed that the most likely hotspot emerged in three sub-regions in the years 2013-2014. The most likely hotspots in monthly data appeared in the month of July to October in each year and showed a strong periodic trend.