High-Resolution Wind Simulation over Incheon International Airport with the Unified Model’s Rose Nesting Suite from KMA Operational Forecasts

Venkatraman Prasanna,최희욱,정지아,이영곤,김백조 한국기상학회 2018 Asia-Pacific Journal of Atmospheric Sciences Vol.54 No.2

This study employs the Unified Model (UM) with the rose nesting suite at 300-m resolution to construct a high spatial and temporal resolution wind simulation model for predicting wind gusts over the Incheon International Airport (IIA). The model can enable efficient aircraft operation and avert accidents due to sudden wind gusts. Simulation results with different inputs from the Korea Meteorological Administration (KMA) operational data assimilation and prediction systems are compared with an observed dataset. The 300-m nested prediction systems are built using the 17 km Global Prediction System (GDAPS) and 1.5 km Local Prediction System (LDAPS) of KMA. They are downscaled to 300 m resolution using five and three nesting domains from the GDAPS and LDAPS, respectively. The model results are validated against automated weather stations (AWS) to determine the accuracy of the UM for simulating high-resolution winds over the IIA. Both nesting suites are identical, with the only difference being their initial (IC) and lateral boundary conditions (LBC). The major difference between LDAPS and GDAPS downscaled model results is that the GDAPS downscaled system has a lower wind direction RMSE and the LDAPS downscaled system has a lower wind speed RMSE for up to 48 hours of verification against observations; thus, it is better than the GDAPS downscaled system. Two case studies were performed; one for wind gust conditions and one for vertical wind shear over the IIA. The 300 m model performs better in both cases, making it useful for wind gust and wind shear predictions over the airport.

Evaluation of South Asian Summer Monsoon Interannual Variability in the CMIP5-AMIP Atmospheric General Circulation Models

Venkatraman Prasanna,Jai-ho Oh,Sumin Woo,In-Won Kim 한국기상학회 2015 한국기상학회 학술대회 논문집 Vol.2015 No.10

Coccygeal Morphology on Multislice Computed Tomography in a Tertiary Hospital in India

Venkatraman Indiran,Vadivalagianambi Sivakumar,Prabakaran Maduraimuthu 대한척추외과학회 2017 Asian Spine Journal Vol.11 No.5

Study Design: A retrospective, cross-sectional study of 213 patients who presented for abdominal computed tomography (CT) scans to assess coccygeal morphology in the Indian population. Purpose: There have been relatively few studies of coccygeal morphology in the normal population and none in the Indian population. We aimed to estimate coccygeal morphometric parameters in the Indian population. Overview of Literature: Coccygeal morphology has been studied in European, American, Korean, and Egyptian populations, with few differences in morphology among populations. Methods: A retrospective analysis of 213 abdominal CT scans (114 males and 99 females; age, 7–88 years; mean age, 47.3 years) was performed to evaluate the number of coccygeal segments, coccyx type, sacrococcygeal and intercoccygeal fusion and subluxation, coccygeal spicules, sacrococcygeal straight length, and sacrococcygeal and intercoccygeal curvature angles. Results were analyzed for differences in morphology with respect to sex and coccyx type. Results: Types I and II coccyx were the most common. Most subjects had four coccygeal vertebrae; 93 subjects (43.66%) had partial or complete sacrococcygeal fusion. Intercoccygeal fusion was common, occurring in 193 subjects. Eighteen subjects had coccygeal spicules. The mean coccygeal straight length was 33.8 mm in males and 31.5 mm in females; the mean sacrococcygeal curvature angle was 116.6° in males and 111.6° in females; the mean intercoccygeal curvature angle was 140.94° in males and 145.10° in females. Conclusions: Type I was the most common coccyx type in our study, as in Egyptian and Western populations. The number of coccygeal vertebrae and prevalence of sacrococcygeal and intercoccygeal fusion in the Indian population were similar to those in the Western population. The mean coccygeal straight length and mean sacrococcygeal curvature angle were higher in males, whereas the intercoccygeal curvature angle was higher in females. Information on similarities and differences in coccygeal morphology between different ethnic populations could be useful in imaging and treating patients presenting with coccydynia.

Development of daily gridded rainfall dataset over the Ganga, Brahmaputra and Meghna river basins

Prasanna, Venkatraman,Subere, Juvy,Das, Dwijendra K.,Govindarajan, Srinivasan,Yasunari, Tetsuzo John Wiley Sons, Ltd 2014 Meteorological applications Vol.21 No.2

<P><B>Abstract</B></P><P>The India Meteorological Department (IMD) gridded rainfall dataset, the 47 Bangladesh gauge rainfall observations and the Tropical Rainfall Measuring Mission (TRMM) 3B42V6 satellite data are used in the present analysis. The nearest neighbour interpolation scheme is used, wherein the interpolated values are computed from a weighted sum of observations. The Bangladesh daily gauge measured rainfall is interpolated into regular grids of 0.5° × 0.5° resolution every day from January 1988 to December 2007 and appended with the daily gridded dataset of the IMD over the Indian region. A similar resolution dataset of 0.5° × 0.5° for the TRMM‐3B42V6 data from January 1998 to December 2007 is created from the original data of 0.25° × 0.25° resolution. To produce a merged rainfall product, all the gridded datasets are merged. The merging of datasets is done in such a way as to include the highest rainfall at each grid point from the three products. Based on the three available sets of daily observations (IMD dataset (1° × 1°), TRMM‐3B42 (0.25° × 0.25°) and 46 daily station observations over Bangladesh), a dataset of 0.5° × 0.5° resolution on a daily scale is generated. The focus of this study is to compare the TRMM‐3B42V6 rainfall data over the Ganga, Brahmaputra and Meghna (GBM) domain with observed point gauge data, and assess the possibility of using them for application in real time flood forecasting as well as to serve as a comparison tool for the baseline simulation of high resolution atmospheric models aimed at flood forecasting and climate change projections. Copyright © 2012 Royal Meteorological Society</P>

Depinning of the ferroelectric domain wall in congruent LiNbO₃

Gopalan, Venkatraman,Phillpot, Simon R. American Institute of Physics 2016 Applied Physics Letters Vol.109 No.8

Zika virus infection of adult and fetal <i>STAT2</i> knock-out hamsters

Siddharthan, Venkatraman,Van Wettere, Arnaud J.,Li, Rong,Miao, Jinxin,Wang, Zhongde,Morrey, John D.,Julander, Justin G. 3M Company 2017 Virology Vol.507 No.-

<P><B>Abstract</B></P> <P>Zika virus (ZIKV) infection was investigated in adult and fetal <I>STAT2</I> knock-out (KO) hamsters. Subcutaneous injection of ZIKV of adults resulted in morbidity, mortality, and infection of the uterus, placenta, brain, spinal cord, and testicles, thus providing an opportunity to evaluate congenital ZIKV infection in a second rodent species besides mice. ZIKV-infected cells with morphologies of Sertoli cells and spermatogonia were observed in the testes, which may have implications for sexual transmission and male sterility. Neonates exposed as fetuses to ZIKV at 8 days post-coitus were not smaller than controls. Nevertheless, infectious virus and ZIKV RNA was detected in some, but not all, placentas and fetal brains of KO hamsters. <I>STAT2</I> KO hamsters may be useful for addressing sexual transmission, pathogenesis, routes of fetal infection, and neurological disease outcomes, and may also be used in antiviral or vaccine studies to identify intervention strategies.</P> <P><B>Highlights</B></P> <P> <UL> <LI> Infection of <I>STAT2</I> knock-out hamsters resulted in morbidity and mortality. </LI> <LI> The uterus, placenta, brain, spinal cord, and testicles were infected. </LI> <LI> ZIKV infected cells with morphologies of Sertoli cells and spermatogonia. </LI> <LI> ZIKV was detected in some, but not all, placentas and fetal brains of KO hamsters. </LI> <LI> Fetuses exposed to ZIKV were not smaller than controls. </LI> </UL> </P>

Role of Anatomical Landmarks in Identifying Normal and Transitional Vertebra in Lumbar Spine Magnetic Resonance Imaging

Devimeenal Jagannathan,Venkatraman Indiran,Fouzal Hithaya,M. Alamelu,S. Padmanaban 대한척추외과학회 2017 Asian Spine Journal Vol.11 No.3

Study Design: Retrospective study. Purpose: Identification of transitional vertebra is important in spine imaging, especially in presurgical planning. Pasted images of the whole spine obtained using high-field magnetic resonance imaging (MRI) are helpful in counting vertebrae and identifying transitional vertebrae. Counting vertebrae and identifying transitional vertebrae is challenging in isolated studies of lumbar spine and in studies conducted in low-field MRI. An incorrect evaluation may lead to wrong-level treatment. Here, we identify the location of different anatomical structures that can help in counting and identifying vertebrae. Overview of Literature: Many studies have assessed the vertebral segments using various anatomical structures such as costal facets (CF), aortic bifurcation (AB), inferior vena cava confluence (IC), right renal artery (RRA), celiac trunk (CT), superior mesenteric artery root (SR), iliolumbar ligament (ILL) psoas muscle (PM) origin, and conus medullaris. However, none have yielded any consistent results. Methods: We studied the locations of the anatomical structures CF, AB, IC, RRA, CT, SR, ILL, and PM in patients who underwent whole spine MRI at our department. Results: In our study, 81.4% patients had normal spinal segmentation, 14.7% had sacralization, and 3.8% had lumbarization. Vascular landmarks had variable origin. There were caudal and cranial shifts with respect to lumbarization and sacralization. In 93.8% of cases in the normal group, ILL emerged from either L5 alone or the adjacent disc. In the sacralization group, ILL was commonly seen in L5. In the lumbarization group, ILL emerged from L5 and the adjacent disc (66.6%). CFs were identified at D12 in 96.9% and 91.7% of patients in the normal and lumbarization groups, respectively. The PM origin was observed from D12 or D12–L1 in most patients in the normal and sacralization groups. Conclusions: CF, PM, and ILL were good identification markers for D12 and L5, but none were 100% accurate.

HVS Weighted Progressive Image Transmission using LOT / CVQ

Chansik Hwang,S. Venkatraman,K. R. Rao 한국통신학회 1993 Asia-Pacific Conference on Communications Vol.2 No.1

Mechanical properties, thermal profiles, and microstructural characteristics of Al-8 %SiC composite welded using pulsed current TIG welding

Sivachidambaram Pichumani,Raghuraman Srinivasan,Venkatraman Ramamoorthi 대한기계학회 2018 JOURNAL OF MECHANICAL SCIENCE AND TECHNOLOGY Vol.32 No.4

This experimental study on Al-SiC composite investigated the temperature distribution and microstructural characterization during pulsed current tungsten inert gas (PCTIG) welding. The parameters considered for PCTIG welding were peak current, base current, pulse frequency, and pulse on time. Experiments were designed and conducted using L 9 orthogonal array technique. Regression model was developed to predict the ultimate tensile strength, bending load, cooling rate, and peak temperature. Statistical software was used to obtain the optimal PCTIG welding parameters, such as peak current of 160 A, base current of 60 A, pulse on time of 50 %, and pulse frequency of 5 Hz to attain desired result, including increased peak temperature of 446 °C, increased ultimate tensile strength of 138 MPa, and high cooling rate of 20 °C/s. Fine grain structures were also observed in weld region. Additionally, SEM fractography showed the difference in fracture surface between the PCTIG welding effects of different welding conditions. Statistical software was also used in identifying significant factors that caused improvement in weld strength, grain refinement in weld zone, and high cooling rate during PCTIG welding of Al-SiC composite.

Development of engineered probiotics with tailored functional properties and their application in food science

Shreyasi Pramanik,Swethaa Venkatraman,Vinoth Kumar Vaidyanathan 한국식품과학회 2023 Food Science and Biotechnology Vol.32 No.4

The potential health benefits of probiotics may not be cognized because of the substantial curtailment in their viability during food storage and passage through the gastrointestinal system. Intestinal flora composition, and resistance against pathogens are among the health benefits associated with probiotic consumption. In the gastric environment, pH 2.0, probiotics dramatically lose their viability during the transit through the gastrointestinal system. The challenge remains to maintain cell viability until it reaches the large intestine. In extreme conditions, such as a decrease in pH or an increase in temperature, encapsulation technology can enhance the viability of probiotics. Probiotic bacterial strains can be encapsulated in a variety of ways. The methods are broadly systematized into two categories, liquid and solid delivery systems. This review emphasizes the technology used in the research and commercial sectors to encapsulate probiotic cells while keeping them alive and the food matrix used to deliver these cells to consumers.