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Tropical Cyclone (TC) is one of the most devastating and deadly weather phenomena and causes loss of life and property. The Bay of Bengal (BoB) is a potentially energetic region for the development of cyclonic storms, accounting about 6% of the global annual total number of cyclonic storms. Accurate prediction of these storms is essential to avoid loss of lives and damage to properties. In this regard, the reduction of errors associated with the track and intensity forecast of the TCs is an important aspect to disseminate more reliable information to the disaster management. The present study examined the performance of Advanced Research Weather Research and Forecasting (WRF-ARW) model for the simulation of track and intensity of TCs over BoB during 1999-2013. The numerical simulations were carried out for 38-cyclones (during 1999-2013) using different microphysical parameterization (MP), cumulus parameterization (CP) and planetary boundary layer (PBL) schemes of the WRF-ARW model. The total 1133 simulations were performed by using 11 combinations with four MPs [Lin et al. (LIN), Ferrier (new Eta) (FERR), WSM 6-class Scheme graupel scheme (WSM6) and Thompson (THOMP)], four CPs [Kain-Fritsch (KF), Betts-Miller-Janjic (BMJ), Grell-Devenyi (GD) and New Grell Scheme (NG)] and three PBLs (Yonsei University scheme (YSU), Mellor-Yamada-Janjic (Eta) TKE (MYJ) and Asymmetrical Convective Model version 2 (ACM2)] to identify the best logical combination of these schemes to predict the track and intensity of TCs over BoB. The best combination of CP and PBL schemes were more influenced the simulations of intensity and track of the cyclones compared to the MP schemes. Further, the simulations were conducted for intense storms with different initial conditions and suggested that the combination of KF + LIN + YSU provided better simulations of the storms for 72h over the BoB and also observed the decreased track error from 1999 to 2013 cyclones. This clearly indicated that the improvement in the initial conditions and parameterization schemes of the WRF-ARW model. This study is very useful for the cyclone warning centers, disaster management centers, real-time governance system and researchers to provide better management for coastal community during the cyclone events.

ZnO nanoparticles (nps) have wide range of applications and improve the optical parameters of molecules of soft liquid crystalline (LC) materials. The present paper mainly discusses the optical studies on LC materials regarding p-n-butyloxybenzoic acid (4oba) and p-n-butylbenzoic (4ba) compound along with homogeneous dispersion of ZnO nps in lower weight concentration, i.e., 1, 1.5, 2 and 2.5 wt%. The existence and size of ZnO nps in LC compounds are well determined through spectroscopic techniques such as scanning electron microscopy (SEM) and X-ray diffraction (XRD). The temperatures of LC compounds and phase transitions are determined by using polarizing optical microscopy (POM) and differential scanning calorimetry (DSC) which is found to decrease with increasing concentration of dispersed ZnO nps. Image enhancement with visual quality matrix method is used to improve the quality of the image. Specially designed wedge-shaped modified spectrometer is used to determine the refractive indices with different wavelengths (460, 500, 570 and 635 nm). The refractive indices measured are fitted with two and three coefficient Cauchy model. Further, the order parameter S of the molecules of 4ba and 4oba with dispersed ZnO nps are determined by molecular field models namely Kuczynski, Vuks and effective geometry model, respectively. From the data, it is found that the values of birefringence (δn) and order parameter (S) of the molecules of 4oba and 4ba are enhanced with the dispersion of ZnO nps with increasing weight concentrations in the stabilized nematic thermal region.

The 90-day BCR-ABL1 (breakpoint cluster region-Abelson 1) level has been one of the accepted milestones for predicting the molecular response in patients with chronic myeloid leukemia (CML). The rate of decline in BCR-ABL1 has been considered a better predictor of the response but has not been uniformly accepted. A paucity of evidence is available to predict the accuracy of the rate of decline in the Indian context. Therefore, we tested the accuracy of the rate of decline of BCR-ABL1 in predicting the molecular response compared with the single 90-day values in a retrospective cohort study of selected cancer centers in south India.Patients with chronic-phase CML diagnosed from January 2013 to December 2018, the serial BCR-ABL1 levels were estimated at 0, 45, and 90 days, 6 months, and 1 year. Data on patient demographics, risk stratification assessed using the Sokal and EUTOS (European Treatment and Outcome Study) scores were extracted using a mobile-based data capture tool from the medical records of the enrolled patients. The halving time, determined by log reduction, was compared with the 90-day BCR-ABL1 values using the receiver operating characteristic curve for the major and complete molecular response at 6 months and 1 year as standards. Accuracy was determined from the area under the curve. The cutoff for the halving time was chosen to balance the sensitivity and specificity.The rate of decline had more predictive accuracy compared with the 90-day BCR-ABL1 values (area under the curve for rate of decline, 0.83; 90-day, 0.80). A halving time of 20 days identified 95% of the patients who had achieved major molecular response at 12 months compared with 80% using the single 90-day BCR-ABL1 response.The halving time of BCR-ABL1 appears promising as a predictor of the outcomes for patients with CML.

With the rapid growth in Technology in terms of multimedia contents such as Biometrics, Facial recognition etc. Facial detection got much attention over the past few years. Face recognition describes a biometric technology that attempts to establish an identity. In this paper, I would like to review about a facial recognition system using machine learning especially, using support vector machines. In any case, point of this exploration is to give extensive writing survey over face acknowledgment alongside its applications. Furthermore, after top to bottom conversation, a portion of the significant discoveries are given in end.

During a total solar eclipse (TSE) on 22 July 2009, atmospheric perturbations were monitored from the surface to thermosphere to understand TSE’s impact on the meteorological (temperature, relative humidity, wind speed, and wind direction) and chemical (O3 and NOx) parameters around Kadapa (14.28°N, 78.42°E), a tropical semi-arid region of India. For this purpose, an experiment was conducted at Yogi Vemana University Campus, Kadapa, India, to measure the temperature, wind speed, wind direction, and concentrations of ozone (O3), NO, NO2, and NOx by using the automatic weather station (AWS) and O3 analyzer. On the eclipse day (22 July 2009), the surface observations at Kadapa showed a reduction in temperature (about 1.1°C) because of the solar insulation. Comparison of the thermal, dynamical (wind), and chemical parameters on the TSE day with control days [preceding (21 July 2009) and succeeding (23 July 2009) the TSE] illustrated the influence of solar eclipse. During the eclipse period, the O3 mixing ratio decreased, while NO2 and NOx increased; however, NO remained unchanged. In addition, radio occultation (RO) temperature profiles from Constellation Observing System for Meteorology, Ionosphere, and Climate (COSMIC)/Formosat Satellite Mission (FORMOSAT-3) and Thermosphere, Ionosphere, and Mesosphere Energetics and Dynamics (TIMED) satellites were utilized to understand the impact of TSE on dynamics of the middle and upper atmosphere from tropopause to the thermosphere. High vertical resolution COSMIC observations revealed that during the solar eclipse, tropopause was cooler with twin peaks (double tropopause). The lower thermosphere between 110 and 130 km became warmer during the TSE, which might be caused by the dynamical response of the atmosphere in this region to the solar eclipse. The experimental data have provided very fine-scale variations of the atmospheric parameters both in time and height and also constituted a new set of results on TSE for further research.

An ultra-low-power, subthreshold switched-capacitor based step-up DC/DC converter is proposed for energy harvesting applications. To enable for low voltage operation, a dynamic body biasing applying to both charge pump and non-overlapping clock generator. As a result, a significant drop in switching loss and leakage current accordingly improves the transient response of output voltage and pumping efficiency. A four-stage cross-coupled voltage doubler circuit is designed with both NMOS and PMOS transistors to provide direct charge flow. The proposed circuit has been implemented in CMOS 0.18 $\mu$m process. Simulation results describe a low start-up voltage of 400 mV with an output voltage of 1.93 V and pumping efficiency of 96.5% while the total circuit dissipates just 2.4 $\mu$W.

In this letter, different types of plasmonic ultra-wide band band-pass filters (UWB-BPFs) have been studied and numerically analyzed. The filters have been designed based on the angular ring resonators (ARRs) and square ring resonators (SRRs) connected with a coupled feed line. The UWB can be realized by suitably adjusting the coupling gaps both sides of the resonator. Based on the ideal characteristics of the proposed ARRs and SRRs, all miniaturized UWB-BPFs are operating at THz frequencies. Multiple transmission zeros are generated to improve the selectivity of the filter. All simulated results have been studied using CST Microwave studio suite. The transmission performance is explained by the resonance condition, which agrees well with the numerical simulation or theoretical calculation. This letter provides a promising application for plasmonic UWB-BPFs and plasmonic integrated optical circuits.

Association of lower tropospheric variations with the cold point tropopause (CPT) is examined on inter-seasonal basis over the tropical region (30°N-30°S) during 2007–2010 using COSMIC/FORMOST-3 Radio Occultation (RO) data. Temperature analyses for this association are shown over different regions of the globe having contrast topography namely over Western Pacific sector, Indian sector, and African sector. Correlation coefficient (r), taken as a measurement of association, show specific longitudinal differences between the lower troposphere (from 1 km to 5 km height) and the CPT. The northern and southern hemispheres show contrast coupling of temperature variation between lower tropospheric region and the CPT. Land and ocean effects are found to contribute in a different way to the correlation coefficient. Analyses show symmetrical structure of ‘r’ on both sides of the equator over the African region, as data include mostly land region on both side of equator. Data represent positive correlation (r ~ 0.5) over 15°–20° latitudes on either side of the equator over the African region, suggesting strong hold of the inter-seasonal variation of solar diabatic heating influence over the tropic of Cancer and tropic of Capricorn. On the other hand, there is a contrast behaviour over the Indian region, ‘r’ is nearly negative (~− 1.0) each year in the southern hemisphere (SH) and positive (~ 0.4) in the northern hemisphere (NH) with a maxima near tropic of Cancer. Western Pacific region is found to display a linear increase in ‘r’ from negative (~− 1.0) in SH to positive (~ 0.8) in NH. In general, ‘r’ (positive) maximizes over the land region around 15°–20° latitudes, suggesting a control of in phase inter-seasonal solar heating on the coupling of boundary layer/lower troposphere and CPT region, whereas it turns negative over water body. Analyses suggest that variabilities in CPT over different regions of globe show significant inter-seasonal association with the lower troposphere. Thus CPT variabilities are not only governed by QBO, ENSO, gravity waves and Kelvin wave system as reported in earlier studies but also considerably affected by inter-seasonal changes taking place in the lower troposphere.

Raindrop size distribution (RSD) characteristics in before landfall (BLF) and after landfall (ALF) of three tropical cyclones (JAL, THANE, and NILAM) induced precipitations are investigated by using a laser-based (PARticleSIze and VELocity - PARSIVEL) disdrometer at two different locations [Kadapa (14.47°N, 78.82°E) and Gadanki (13.5°N, 79.2°E)] in semi-arid region of southern India. In both BLF and ALF precipitations of these three cyclones, convective precipitations have higher mass weighted mean diameter (Dm) and lower normalized intercept parameter (log10Nw) values than stratiform precipitations. The radar reflectivity (Z) and rain rate (R) relations (Z=A*Rb) showed distinct variations in BLF and ALF precipitations of three cyclones. BLF precipitation of JAL cyclone has a higher Dm than ALF precipitation. Whereas, for THANE and NILAM cyclones ALF precipitations have higher Dm than BLF. The Dm values of three cyclones (both in BLF and ALF) are smaller than the Dm values of the other (Atlantic and Pacific) oceanic cyclones. Interaction of different regions (eyewall, inner rainbands, and outer rainbands) of cyclones with the environment and underlying surface led to RSD variations between BLF and ALF precipitations through different microphysical (collision-coalescence, breakup, evaporation, and riming) processes. The immediate significance of the present work is that (i) it contributes to our understanding of cyclone RSD in BLF and ALF precipitations, and (ii) it provides the useful information for quantitative estimation of rainfall from Doppler weather radar observations.

This work presents a fully integrated six-phase voltage doubler (SPVD) circuit with both NMOS driver circuit and PMOS driver circuit for modern smart electronic systems and verified in a 180 nm CMOS process. An optimized gate control technique is applied for charge transfer switches (CTS) using driver circuits to reduce reversion losses thereby increasing voltage conversion ratio and pumping efficiency effectively. For 1.8 V supply, the proposed circuit offers better performance relative to similar work reported in literature in terms of good voltage conversion ratio of 1.98 with an output voltage 3.58 V. Further, it can drive loads upto 0 to 1.1 mA.

In this paper, the power dissipation model to estimate the junction temperature of LDO circuits is presented. The Steady-state ripple magnitude of LDO circuits will be affected by ripple currents and clock frequency. Therefore, the proposed model considers ripple voltage, reference voltage and, clock frequency. Power dissipation proportional to input parameters of the model and it is a function of $I_{load}, v_{ripple}, v_{ref}, f_{clk}$ . Power dissipation estimated for four different test cases (changing the input parameter model). The junction temperatures obtained are 49.7 °C, 49.7 °C, 55.8°C and 40.4°C for test cases I, II, III, IV, respectively. Finally, reliability prediction using Arrhenius-Weibull relation performed to identity at which test case LDO circuit demonstrates high operation life.

The objective of paper is to analyze the performance of the Vapour Compression Refrigeration (VCR) system by change the profile of condenser coil and with sub cooling system. An experiment is conducted on VCR system with different condenser profiles and also with sub cooling system at steady state evaporator temperature and calculated mass flow rate of refrigerant, refrigeration effect, works done and COP. From results of experiment, Refrigeration Effect in case of helical coiled condenser is increased by 3 kJ compared to straight coiled condenser and Refrigeration Effect in case of helical coiled condenser with sub-cooling is increased by 15.3% compared to helical coiled condenser without sub-cooling. COP in case of helical coiled condenser is increased by 20% compared to straight coiled condenser and COP in case of helical coiled condenser with sub-cooling is increased by 9.7% compared to helical coiled condenser without sub-cooling.

This paper explores the characteristics of raindrop spectra in terms of raindrop size distribution (RSD) using 4 years of Joss–Waldvogel disdrometer data over Palau islands (7 o 20′ N, 134 o 28′ E) in Western Tropical Pacific ocean. The RSD characteristics are studied in two seasons (easterly monsoon—EM and westerly monsoon—WM) using three (stratiform, deep convection, and shallow convection) rain types identified from collocated 1290-MHz wind profiler radar (WPR). In addition to the ground-based sensors observations, TRMM and MODIS satellite-derived rain parameters and atmospheric parameters are utilized to study RSD characteristics. RSD characteristics stratified on the basis of rainrate show that the mean values of raindrop concentrations of small (medium and larger) drops are same (more) in WM compared to EM season. Normalized gamma distribution of RSD shows that the mean value of mass-weighted mean diameter, D m (normalized intercept parameter, log 10 N w ), is higher (lower) in WM than the EM season. In addition, the mean value of D m (log 10 N w ) is higher (lower) in deep convective precipitation as compared to the other two types of precipitation (stratiform and shallow convection) in both monsoon periods. In conjunction with the remote sensing data (MODIS & TRMM), RSD shows that the presences of cold clouds which extend to deeper altitudes are responsible for the higher D m during WM season. The immediate significance of the present work is that (1) it contributes to our understanding of seasonal variations of RSD and distribution of different rain types, and (2) it provides information which is useful for quantitative estimation of rainfall from weather radar observations.

Long-period modulations are shown in aerosol optical depth measured by the Microtops II Sun photometer over a high-altitude site the central Himalayan region (Nainital, 29.4° N, 79.5° E, 1958 m a.m.s.l.) for the first time. Fourier analysis of aerosol optical depth showed dominant 25–45 day oscillations observed in MODerate-resolution Imaging Spectro radiometer data. Further, a Hovmiller diagram showed westward (northward) propagation at a different longitude (latitude), confirming that the modulations are associated with Rossby waves. It is also shown that the Rossby wave amplitude causes an additional warming of 4.16 ± 0.98 W m−2 over the observational site. Hence, the present study illustrates the importance of wave-induced aerosol dynamics and the corresponding radiative effects.

Dispersing small amounts of solid nano particles into base-fluid has a significant impact on the thermo-physical properties of the base-fluid. These properties are utilized for effective capture and transportation of solar energy. This paper attempts key idea for harvesting solar energy by using alumina nanofluid in concentrating parabolic trough collectors. An experimental study is carried out to investigate the performance of a parabolic trough collector using Al2O3-H2O based nanofluid. Results clearly indicate that at same ambient, inlet temperatures, flow rate, concentration ratio etc. hike in thermal efficiency is around 5-10 % compared to the conventional Parabolic Trough Collector (PTC). Further, the effect of various parameters such as concentration ratio, receiver length, fluid velocity, volume fraction of nano particles has been studied. The different flow rates employed in the experiment are 2 ml/s, 4 ml/s and 6 ml/s. Volumetric concentration of 0.02%, 0.04% and 0.06% has been studied in the experiment. Surfactants are not introduced to avoid bubble formation. Tracking mode of parabolic trough collector is manual. Results also reveal that Al2O3-H2O based nanofluid has higher efficiency at higher flow rates.

The purpose of thermal energy storage systems (TES) is to store the heat energy supplied to it for a considerable time period and give the energy back when ever need arise. On many of occasions, part of the heat energy of various systems is unutilized. If this excess heat energy be stored in such systems as TESS, utilization of energy improves. If the use of such systems is widespread, fuel is conserved and national economy is saved.Different materials can be used in TESS to store heat energy and in the present work two such materials, which are popular phase change materials (PCM) namely (a) Paraffin (b) Stearic acid are used and subsequently the performance of the TESS is studied. The PCMs are used in the form of spherical capsules made up of high density poly ethylene (HDPE) of diameter 58 mm. Charging time and amount of heat energy recovered are studied for the two PCMs mentioned above and compared. Though paraffin as PCM gives little better heat energy recovery, performance of both the materials are almost the same. Hence as the cost of stearic acid is less when compared to paraffin on economical grounds and on ease of availability basis stearic acid has advantages over paraffin.

Efficient and reliable thermal energy storage systems are required for solar applications to overcome their existing discontinuous nature and abrupt change in weather conditions. In Thermal energy storage system, Phase Change Material (PCM) is used as latent heat storage material has received greater attention in recent era. It has better heat storage capacity and isothermal nature during charging and discharging processes. Besides having high energy density most of the PCMs have an unacceptable low thermal conductivity. To over come this drawback heat transfer enhancement techniques are required for any Latent Heat Thermal Energy Storage (LHTS) application comprises with PCMs. One of the best suited method is the addition of nanoparticles into base fluid to enhance its thermal performance. Phase change materials (PCMs) have a high ability to store energy and have an excellent characteristic of constant temperature in the course of absorbing or releasing energy. In present work, Al2O3 nanoparticles are added in 0.02 and 0.08% volume concentration into the base fluid (water) to enhance its thermal performance.

In this paper, four years (April, 2003–March, 2007) of wind profiler radar (WPR) observations, Tropical Rainfall Measuring Mission measurements, radiosonde and automatic weather station data are utilized to characterize melting layer/bright band (caused due to the melting of hydrometeors when the precipitation has a significant stratiform cloud contribution) variability during easterly and westerly monsoon periods over Palau in Western Pacific Ocean. Four years observational results show that presence of stratiform precipitation is more in Westerly monsoon compared to Easterly monsoon. However, bright band height (BBH) is lower in Westerly monsoon. It is also observed that the BBH during the year 2006 is higher than 2005 possibly due to El Nino effect.

Diabetic nephropathy (DN) is a secondary complication of both type 1 and type 2 diabetes, resulting from uncontrolled high blood sugar. 30–40 % of diabetic patients develop DN associated with a poor life expectancy and end-stage renal disease, causing serious socioeconomic problems. Although an exact pathogenesis of DN is still unknown, several factors such as hyperglycemia, hyperlipidemia, hypertension and proteinuria may contribute to the progression of renal damage in diabetic nephropathy. DN is confirmed by measuring blood urea nitrogen, serum creatinine, creatinine clearance and proteinuria. Clinical studies show that intensive control of hyperglycemia and blood pressure could successfully reduce proteinuria, which is the main sign of glomerular lesions in DN, and improve the renal prognosis in patients with DN. Diabetic rodent models have traditionally been used for doing research on pathogenesis and developing novel therapeutic strategies, but have limitations for translational research. Diabetes in animal models such as rodents are induced either spontaneously or by using chemical, surgical, genetic, or other techniques and depicts many clinical features or related phenotypes of the disease. This review discusses the merits and demerits of the models, which are used for many reasons in the research of diabetes and diabetic complications.

The effect of quasi-biennial oscillation (QBO) on the temperature of cold point tropopause (T-CPT) and its height (H-CPT) is being investigated using radio occultation measurements by COSMIC/FORMOSAT-3. Observations comprising of 935,863 numbers of occultations have been used to study the zonal mean seasonal variability in T-CPT and H-CPT from January 2007 to December 2011. Results are shown over 30°N–30°S geographic latitudes. In general, T-CPT is found to be the coldest in February and the warmest in August. H-CPT attains maximum height during December–February and minimum during July–August. Interestingly, H-CPT shows maxima at off-equator region (around 20°N or 20°S) during all the seasons in both hemispheres. H-CPT at off-equatorial region, in reference to the equatorial region, is slightly higher (~ 1.0 km) during winter as compared to monsoon season (~ 0.5 km) in Northern Hemisphere (NH). Inter-annual variation in T-CPT and H-CPT found to be clearly influenced by the QBO. Westerly (easterly) phase generates warm (cold) T-CPT, which consequently results a decrease (increase) in H-CPT. It is concluded that QBO induces the changes in T-CPT by as much as 2 °C and in H-CPT by 0.5 km.

A simple, fast, and sensitive capillary electrophoretic method was developed for determining two genotoxic impurities hydrazine and methylhydrazine and eight alkyl amines at trace levels in pharmaceutical substances using indirect photometric detection. The method development involved a systematic screening of various cationic visualizing reagents and optimization of separation conditions to obtain the best resolution and sensitivities. The optimized method was validated for specificity, precision, linearity, and accuracy. Linear calibration curves (R > 0.99) were obtained for all analytes in the range LOQ–200 % of nominal concentrations. The developed CE method was effectively implemented for estimating hydrazine and alkylamines in several active pharmaceutical ingredients (APIs).

The Indian subcontinent is the worst affected part of the world due to tropical cyclones (TCs). This region account for ~7 % 0.of the total number of global TCs (Gray 1968). The formation of TCs is more pronounced over Bay of Bengal (BOB) compared to Arabian Sea. A large number of TCs form over the BOB region generally move in the north and north-west directions and make landfall along the coastal regions of India, Bangladesh, and Myanmar (Tyagi et al. 2010; Mohapatra et al. 2012, 2015). These TCs have been responsible for the damage of property, loss of agriculture crops, and thousands of human lives (Paul 2010). In the BOB, TC genesis is highly seasonal with primary maximum in the post-monsoon season (October to December) and secondary maximum during pre-monsoon season (April and May). Hence, there is a need to improve the understanding and the forecast of TC over the Indian Ocean region. Several dynamic models have been used for the forecasting of the track and intensity of TC over specific regions. There has been significant improvement in recent years in terms of track, intensity and landfall forecasts (Mohapatra et al. 2013a,b,c). However, the accurate track and intensity predictions of TCs remain a challenging task for atmospheric scientists and the research community.

Objectives: To study the seasonal variations of two important atmosphere stability indices, i.e. Convective Available Potential Energy (CAPE) and Convective Inhibition (CIN) for the selected years, i.e. from 2007 to 2012 using the COSMIC (Constellation Observing System for Meteorology, Ionosphere, and Climate) Radio occultation (RO) technique. Methods/Analysis: We used the COSMIC RO technique as we consider that it provides more accurate, all-weather, round the-clock and global coverage of the lower atmosphere and ionosphere constituents with unprecedented resolutions. Further, we used the lower atmosphere database provided by the COSMIC RO technique in order to study the above two parameters (CAPE & CIN). Findings: It was found that, for the very first time, the consistency of wavy nature in CAPE seasonal trends which are confined to northern and southern hemispheres alternatively. The wavelike nature in CAPE trends seems to be following Inter- Tropical Convergence Zone (ITCZ) movement and, in such case, the CAPE trends may be useful to ascertain the ITCZ movements during different seasons of a year and the CAPE magnitude shows higher values over land than oceanic regions, which confirms the consistency of their calculations. In this regard, the trends of both CAPE and CIN have shown a close bimodal distribution. Applications/Improvement: As a result, we find better correlations of both CAPE and CIN computed through the atmospheric data measured with the COSMIC RO and collocated Radiosonde technique when the profile data are reaching to the near-surface of the Earth.

Raindrop size distribution (RSD) characteristic variations between two southern Indian stations [Gadanki (13.5° N, 79.2° E) Kadapa (14.47° N, 78.82° E)] using ground based parsivel disdrometer data are studied. Number concentration of mid and large drops is more over Gadanki when compared to Kadapa precipitation. The mean value of mass weighted mean diameter (D m ) is higher in Gadanki than Kadapa precipitation. Both monthly and diurnal variations of D m show higher values of D m over Gadanki than Kadapa. After classifying the precipitations systems into stratiform and convective, Gadanki has higher (lower) D m than Kadapa in stratiform (convective).

Collocated measurements of the boundary layer evolution and surface ozone, made for the first time at a tropical rural site (Gadanki 13.5 ◦ N, 79.2 ◦ E, 375 m amsl) in India, are presented here. The boundary layer related observations were made utilizing a lower atmospheric wind profiler and surface ozone observations were made using a UV analyzer simultaneously in April month. Daytime average boundary layer height varied from 1.5 km (on a rainy day) to a maximum of 2.5 km (on a sunny day). Correlated day-to-day variability in the daytime boundary layer height and ozone mixing ratios is observed. Days of higher ozone mixing ratios are associated with the higher boundary layer height and vice versa .I t is shown that higher height of the boundary layer can lead to the mixing of near surface air with the ozone rich air aloft, resulting in the observed enhancements in surface ozone. A chemical box model simulation indicates about 17% reduction in the daytime ozone levels during the conditions of suppressed PBL in comparison with those of higher PBL conditions. On a few occasions, substantially elevated ozone levels (as high as 90 ppbv) were observed during late evening hours, when photochemistry is not intense. These events are shown to be due to southwesterly wind with uplifting and northeasterly winds with downward motions bringing ozone rich air from nearby urban centers. This was further corroborated by backward trajectory simulations.

Raindrop size distribution (RSD) characteristics in summer season rainfall of two observational sites [Taiwan (24o 58’ N, 121o 10’ E) and Palau (7o 20’ N, 134o 28’ E)] in western Pacific are studied by using five years of impact type disdrometer data. In addition to disdrometer data, TRMM, MODIS, and ERA-Interim data sets are used to illustrate the dynamical and microphysical characteristics associated with summer season rainfall of Taiwan and Palau. Taiwan and Palau's raindrop spectra showed a significant difference, with a higher concentration of mid and large drops in Taiwan than Palau rainfall. RSD stratified on the basis of rain rate showed a higher mass-weighted mean diameter (Dm) and a lower normalized intercept parameter (log10Nw) in Taiwan than Palau rainfall. Precipitation classification into stratiform and convective regimes showed higher Dm values in Taiwan than Palau. Furthermore, for both the locations, the convective precipitation has a higher Dm value than stratiform precipitation. The radar reflectivity - rain rate relations (Z= A*Rb) of Taiwan and Palau showed a clear variation in the coefficient and a less variation in exponent values. Terrain-influenced clouds extended to higher altitudes over Taiwan resulted with higher Dm and lower log10Nw values as compared to Palau.

This paper describes some of the microphysical and kinematic properties of precipitating systems associated with a typhoon using Chug-Li VHF radar. In order to gain a better understanding of these mechanisms and the vertical structure of the precipitation associated with a typhoon at different stages of development, an analysis has been carried out of the radar back-scattered signal in order to obtain the power, velocity and velocity width of the Doppler spectrum of clear air and hydrometeors. The vertical profiles of raindrop size distribution (DSD) parameters are estimated through model-based regression analysis. The study reveals that during a typhoon, different convective and stratiform types of precipitation occur at different times with varying intensities. This study also reports on some of the characteristic features of the convective systems observed during the typhoon.

The interaction of the storm circulation with the Central Mountain Range (CMR) of Taiwan is studied with a wind profiler located at the leeside during the invasions of two (Kaemi (200605) and Bopha (200609)) typhoons. The moderate typhoon Kaemi upgraded from a tropical depression on 21 July 2006. It then was made landfall at 15:45 UTC on 24 July 2006 near Cheng-Kung. The weak typhoon Bopha formed at about 12:00 UTC on 5 August 2006 and also landed near Cheng-Kung at around 19:20 UTC on 8 August. A new finding from both typhoons is the vortex splitting into upper and lower parts with the two typhoons that have passed the observation site nearly. For the typhoon Kaemi, demarcation height of the upper-level vortex and lower level is at 2.8 km and passed the site about 3 h earlier than the low-level one. For the typhoon Bopha, the center of the lower-level vortex at 3.5 km locates to the north of the upper-level one at 5.2 km. The re-organization of the split vortexes is found in typhoon Kaemi but not for typhoon Bopha.

This paper has investigated the mesoscale structure and evolution of a Meiyu/Baiu front and precipitation along the front observed in the downstream region of the Yangtze River on 21 June 2002 by using data from intensive observations of upper-air, surface, and five Doppler radars, as well as GMS IR and GANAL re-analysis data. It is found that the front collocated with a large-scale wind shear line. The frontal zone was characterized by a subsynoptic-scale low-level jet (LLJ) to the south and a thermally direct circulation in the middle troposphere south of the surface front. The front evolved from an inactive front with little convection along it to an intensive one triggering a strong meso-α-scale rainband. The front initially intensified mainly in association with the divergence related to the evaporative cooling of precipitation systems north of the front and further developed when strong convection evolved along the front. The meso-α-scale rainband triggered by the front was composed of several meso-β-scale convective systems. Meso-β-scale convective systems were narrow and consolidated in the western part, but wide and weak in the eastern part of the downstream region of the Yangtze River. Three-dimensional kinematic and reflectivity structures of two meso-β-scale convective systems, where one was in the western part and the other was in the eastern part, have been examined comprehensively. In the western part, the convective system evolved in a quasi-steady state and was characterized by a deep and strong convective cell just north of the front and limited stratiform precipitation further north of the front. The orientation of the LLJ to the front was at a sharp angle. The primary updraft triggered by the front sloped largely northward in the lower troposphere and became nearly upright and strong from the middle troposphere. In the eastern part, on the other hand, the convective system changed remarkably with time and was featured by multiple shallow and weak convective cells across the front and extended stratiform precipitation both south and north of convective cells. The LLJ that oriented nearly normal to the front overran the front at lower levels and penetrated far to the north of the front. It appears that the variable structure and evolution of the LLJ would have a great impact on the development of distinct convective systems in the downstream region of the Yangtze River. The mesoscale along-frontal variability of the Meiyu/Baiu frontal zone appears to be responsible for distinct modes of convective organization along the front in a limited distance.

Highways built on expansive (poor) subgrades have experienced an increase in the severity and extent of permanent deformation (rutting) in hot mix asphalt pavements. In the present study, an attempt is made to evaluate the increase in service of the flexible pavements in terms of rutting resistance by stabilizing the expansive subgrades. The study includes evaluation of optimal quantity of fly ash- lime additive for subgrade stabilization, design and construction of a test track with conventional and stabilized subgrade and evaluation of rutting potential using a Medium Scale Accelerated Pavement Rut Tester (MAPRT). The field studies indicated that stabilized subgrade result in an increase in service by 15%.

This paper presents the diurnal and seasonal variation of Turbulence Kinetic Energy (TKE) dissipation rate (e) in the Atmospheric Boundary-Layer (ABL) over a tropical station, Gadanki (13.5° N, 79.2° E) in India. Doppler spectral width measurements made by Lower Atmospheric Wind Profiler (LAWP) operating at 1357 MHz are utilized to estimate e in the height region of 0.5–4.0 km on clear air days. Various non-turbulent spectral broadenings are calculated and separated out from the observed spectral width before estimating e. It is found that in the lower tropospheric height region e is in the range from 10−5.0 to 10−1.0 m2 s−3. e showed significant diurnal variation in the boundary-layer. The larger values of e, 10–2.7 m2 s−3, are noted to be associated with the Convective Boundary-Layer (CBL). The parameter e is also showing significant seasonal variation. In summer and monsoon seasons the boundary-layer depths are observed up to a height of ∼4.0 km while the same are confined to below 2.0 km in post-monsoon and winter seasons.

Bactericidal Activity of Certain Volatile Scent Components of Heteropteran Bugs