On Reverse Super Vertex-Magic Labeling

For a graph G(V, E) an injective mapping f from to the set is a reverse vertex-magic labeling if there is a constant h so that for every vertex where the difference runs over all vertices u adjacent to v . A vertex-magic labeling f is called super vertex-magic labeling if and . A graph G is called a reverse super vertex-magic if there exists a reverse super vertex-magic labeling of G. In this paper, we established some properties of reverse super vertex magic trees and exhibit reverse super vertex-magic labeling of a kite graph.

Evaluations of the Characteristics of the Tropo-Strato-Mesopause Height and Temperature Variability over Bahir Dar, Ethiopia (11.60 N, 37.30 E) Using SABER

The height profile of atmospheric temperature data between 12 km and 100 km was obtained from SABER/TIMED satellite instruments during the year 2016 and used to characterize the three atmospheric pauses temporal variability of height and temperature over Bahir Dar, Ethiopia (11.60 N, 37.30 E). The daily, monthly, and frequency distributions of tropopause-stratopause-mesopause height and temperature are investigated. From the frequency distribution, we had found that of the tropopause-stratopause-mesopause height 17 km, 48 km, and 98 km with the corresponding temperature 192 K, 268 K, and 148 K. The decrement (cooling) trend lines of tropopause height 0.7 K/year and its corresponding tropopause increment temperature has been ~1.5 K/year. The stratopause and mesopause trend lines of height are insignificant and the corresponding decrement (cooling) temperatures are ~3 K/year and ~13 K/year respectively. The mean monthly maximum heights of tropopause 19 km in May with a corresponding maximum temperature of 201 K in September. The maximum stratopause height 49.5 km in February and July and its temperature 268 K and 267 K in February and April respectively. The maximum mesopause height 98 km, 95 km, 97 km in March, Jun, and November respectively, and its maximum temperature 196 K and 198 K in January and July respectively

MUMAP: Modified Ultralightweight Mutual Authentication protocol for RFID enabled IoT networks

Flawed authentication protocols led to the need for a secured protocol for radio frequency identification (RFID) techniques. In this paper, an authentication protocol named Modified ultralightweight mutual authentication protocol (MUMAP) has been proposed and cryptanalysed by Juel-Weis challenge. The proposed protocol aimed to reduce memory requirements in the authentication process for low-cost RFID tags with limited resources. Lightweight operations like XOR and Left Rotation, are used to circumvent the flaws made in the other protocols. The proposed protocol has three-phase of authentication. Security analysis of the proposed protocol proves its resistivity against attacks like desynchronization, disclosure, tracking, and replay attack. On the other hand, performance analysis indicates that it is an effective protocol to use in low-cost RFID tags. Juel-Weis challenge verifies the proposed protocol where it shows insusceptibility against modular operations

Electro Discharge Machining Characteristics of Ti-6Al-4V Alloy: A Grey Relational Optimization

AbstractThe paper presents the grey relational theory based parameter optimisation in electro discharge machining (EDM) of Ti-6Al-4V alloy. The multiple responses optimized are material removal rate (MRR), electrode wear rate (EWR) and surface roughness (SR). The process parameters include duty cycle, pulse current, pulse on time, electrode type and gap voltage. Experiments were conducted using Taguchi L18 orthogonal array. From grey relational analysis, the optimum values found are duty cycle (8%), pulse current (18 Amp), pulse on time (200μsec) and voltage (40V). Experimental results revealed that the copper electrode gives the optimum performance in terms of higher MRR and lower EWR and SR. The optimized process parameters that simultaneously leading to a lower electrode wear ratio and higher material removal rate are then verified through a confirmation experiment

A study on climatological features of the Asian summer monsoon: dynamics, energetics and variability

A continuing goal in the diagnostic studies of the atmospheric general circulation is to estimate various quantities that cannot be directly observed. Evaluation of all the dynamical terms in the budget equations for kinetic energy, vorticity, heat and moisture provide estimates of kinetic energy and vorticity generation, diabatic heating and source/sinks of moisture. All these are important forcing factors to the climate system. In this paper, diagnostic aspects of the dynamics and energetics of the Asian summer monsoon and its spatial variability in terms of contrasting features of surplus and deficient summer monsoon seasons over India are studied with reanalysis data sets. The daily reanalysis data sets from the National Centre for Environmental Prediction/National Centre for Atmospheric Research (NCEP/NCAR) are used for a fifty-two year (1948-1999) period to investigate the large-scale budget of kinetic energy, vorticity, heat and moisture. The primary objectives of the study are to comprehend the climate diagnostics of the Asian summer monsoon and the role of equatorial convection of the summer monsoon activity over India.It is observed that the entrance/exit regions of the Tropical Easterly Jet (TEJ) are characterized by the production/destruction of the kinetic energy, which is essential to maintain outflow/inflow prevailing at the respective location of the TEJ. Both zonal and meridional components contribute to the production of kinetic energy over the monsoon domain, though the significant contribution to the adiabatic generation of kinetic energy originates from the meridional component over the Bay of Bengal in the upper level and over the Somali Coast in the low level. The results indicate that the entire Indian peninsula including the Bay of Bengal is quite unstable during the summer monsoon associated with the production of vorticity within the domain itself and maintain the circulation. The summer monsoon evinces strong convergence of heat and moisture over the monsoon domain. Also, considerable heat energy is generated through the action of the adiabatic process. The combined effect of these processes leads to the formation of a strong diabatic heat source in the region to maintain the monsoon circulation. The interesting aspect noted in this study is that the large-scale budgets of heat and moisture indicate excess magnitudes over the Arabian Sea and the western equatorial Indian Ocean during surplus monsoon. On the other hand, the east equatorial Indian Ocean and the Bay of Bengal region show stronger activity during deficient monsoon. This is reflected in various budget terms considered in this study

Interannual variability of onset of the summer monsoon over India and its prediction

In this article, the interannual variability of certain dynamic and thermodynamic characteristics of various sectors in the Asian summer monsoon domain was examined during the onset phase over the south Indian peninsula (Kerala Coast). Daily average (0000 and 1200 UTC) reanalysis data sets of the National Centre for Environmental Prediction/National Centre for Atmospheric Research (NCEP/NCAR) for the period 1948-1999 were used. Based on 52 years onset date of the Indian summer monsoon, we categorized the pre-onset, onset, and post-onset periods (each an average of 5 days) to investigate the interannual variability of significant budget terms over the Arabian Sea, Bay of Bengal, and the Indian peninsula. A higher difference was noticed in low-level kinetic energy (850 hPa) and the vertically integrated generation of kinetic energy over the Arabian Sea from the pre-onset, onset, and post-onset periods. Also, significant changes were noticed in the net tropospheric moisture and diabatic heating over the Arabian Sea and Indian peninsula from the pre-onset to the post-onset period. It appears that attaining the magnitude of 40 m2 s-2 and then a sharp rise in kinetic energy at 850 hPa is an appropriate time to declare the onset of the summer monsoon over India. In addition to a sufficient level of net tropospheric moisture (40 mm), a minimum strength of low-level flow is needed to trigger convective activity over the Arabian Sea and the Bay of Bengal. An attempt was also made to develop a location-specific prediction of onset dates of the summer monsoon over India based on energetics and basic meteorological parameters using multivariate statistical techniques. The regression technique was developed with the data of May and June for 42 years (1948-1989) and validated with 10 years NCEP reanalysis from 1990 to 1999. It was found that the predicted onset dates from the regression model are fairly in agreement with the observed onset dates obtained from the Indian Meteorology Department

Onset characteristics of the southwest monsoon over India

Dynamic and thermodynamic characteristics of the Asian summer monsoon during the onset phase over the Indian Peninsula (Kerala coast) and its variability are examined with reanalysis data sets. For this study, daily averaged (0000 and 1200 UTC) reanalysis data sets of National Centre for Environmental Prediction-National Centre for Atmospheric Research for the period 1948-99 are used. Based on 52 years of onset dates of the Indian summer monsoon, we categorized pre-onset, onset and post-onset periods (each averaged 5 days) to investigate the mean circulation characteristics and the large-scale energetics of the Asian summer monsoon. It is found that the strength of the low-level Somali jet and upper tropospheric tropical easterly jet increase rapidly during the time of evolution of the summer monsoon over India. Over the Bay of Bengal and the Arabian Sea, predominant changes are noticed in the large-scale balances of kinetic energy, heat and moisture from the pre-onset to the post-onset periods. Prior to the onset of the summer monsoon over India, a zone of flux convergence of heat and moisture is noticed over the eastern sector of the Bay of Bengal and this intensifies in the onset and post-onset periods. During onset of the monsoon over India, the horizontal flux convergence of heat and moisture, as well as diabatic heating, are enhanced over the Arabian Sea. These subsequently increase with the evolution and advancement of the monsoon over India. Further, the dynamics of the evolution processes (15 days before and 30 days after the onset date of the monsoon over Kerala for each annual cycle) are studied over various sectors, such as the Arabian Sea, Bay of Bengal and Indian Peninsula region. The study reveals that the low-level kinetic energy, vertically integrated generation of kinetic energy and net tropospheric moisture over Arabian Sea can be used as potential predictors for the prediction of the possible onset date of the summer monsoon over the Indian Peninsula

Error Modeling Radar Rainfall Estimation Through Incorporating Rain Gauge Data Over Upper Blue Nile Basin, Ethiopia

Accurate and precise measurements of rainfall from weather radar reflectivity data is essential to supplement the limited characterization of spatial and temporal measurements provided by insufficient network and density of rain gauges. While weather radar has high spatial and temporal resolution, it contaminated with various sources of errors due to the conversion of reflectivity to rain rate and the projectile rainfall motion. Error modeling improvement with the application of projectile rainfall motion correction is essential to improve the radar data. However, stile is not well documented for over the world as well as Ethiopia. Therefore, the aim of this study was to generate an error model for weather radar rainfall estimation by incorporating gauge rainfall data over upper Blue Nile basin, Ethiopia. Projectile rainfall motion correction is considered on the data of reflectivity and rain rate to determine empirical error model parameter values. The model parameter values are found, multiplicative factor (a) was 55, the exponent factor (b) was 1.12, standard deviation of proportional error was 0.08 and standard deviation of random error was 0.07. The value of the total error varied from -0.45 to 1.16 mm and the domain of proportional error was greater than random error. After applying the projectile rainfall motion correction, the total error is reduced by 12%. In general, the assumption of projectile method is quite useful for improving the radar data over upper Blue Nile basin in Ethiopia as well as over the world. Hence, we wish to extend this method for other regions