Design and Analysis of the Swaging manufacturing Process Using CAE

Raghu Echempati,허용정 한국산학기술학회 2004 한국산학기술학회논문지 Vol.5 No.5

스웨이징(swaging) 제조 공정의 컴퓨터 시뮬레이션에 관한 연구를 수행하기 위하여 상용 소프트웨어를 사용하였다. 시행오차를 통하여 획득한 경험에 기반을 두어 튜브 스웨이징 공정의 시뮬레이션이 이루어졌으며, 변형 경화 지수(strain hardening exponent) n과 소성계수(plastic modulus) K는 튜브재료의 실제 인장 측정 시험을 통하여 얻어졌다. 두 종류의 서로 다른 다이와 튜브 형상을 사용하여 비교하였다. 전처리는 (HyperMesh(r), 해석은 LS-DYNA(r), 후처리는 LS-TAURUS(r)를의 상용 소프트웨어를 사용하였으며, 본 연구에서 얻어진 결과들을 문헌에서 이용 가능한 결과들과 비교하였다. Computer simulation of a swaging manufacturing process is presented in this paper. Commercially available software has been used to develop the simulation algorithm. Based on the experience gained from trial runs, simulation of a tube swaging process has been carried out. The material parameters “n” (strain hardening exponent) and “K” (plastic modulus) are obtained from actual tensile test measurements of the tube material. Two different geometries for the die and the tube have been used in this work and a comparison made. Numerical simulation of the swaging process has been performed using the commercially available HyperMesh(r) for pre-processing, LS-DYNA(r) for analysis and LS- TAURUS(r) for post-processing. Some of the results obtained from this study are compared with those available in the literature.

Starch Content and Cassava Mosaic Disease Genetic Diversity with Relation to Yield in South Indian Cassava (Manihot esculenta Crantz) Germplasm

Raghu Duraisamy,Senthil Natesan,Sakthi Ambothi Rathinasamy,Raveendran Muthurajan,Jana Jeevan Ramineni,Nageswari Karuppusamy,Pugalenthi Lakshmanan,Mohan Chokkappan,Karthikeyan Gandhi 한국작물학회 2011 Journal of crop science and biotechnology Vol.14 No.3

Cassava, family Euphorbiaceae, is the fifth most important staple food crop. The study of variability and diversity present in diverse cassava accessions maintained at the field genebank of TCRS, TNAU is essential to design the breeding program of cassava in TNAU. Hence, a study was carried out to assess the genetic diversity based on morphological traits and Simple Sequence Repeat (SSR) markers, identifying the SSR markers linked to a cassava mosaic disease-resistant QTL region. Genetic diversity among cassava germplasm accessions was estimated using 28 morphological traits and three SSR markers. The polymorphic information content (PIC) result gives high information for all the SSR markers. Morphological traits revealed 10 clusters and the SSR markers revealed 13 clusters at a similarity coefficient of 2.514 and 0.75, respectively. The SSR marker diversity revealed that the most promising clusters (II and XII) possessing accessions with yield attributing traits and cluster IX were grouped together due to low yield and CMD susceptibility. Morphological descriptors revealed variance for yield contributing traits. The first three principle components accounted for 10.8, 9.1, and 8.4%, respectively. Correlation studies showed significant correlation among yield and yield-attributing traits, which in turn influences yield. The morphological traits diversity reveals that cluster VI was the most promising cluster in which genotypes ME209 and ME460 possess higher yield and starch content with cassava mosaic disease (CMD) resistance. Most of the accessions grouped under cluster X belong to selection from International Centre for Tropical Agriculture (CIAT) collections and the cultivars under clusters I and II were true cassava seed (TCS) selections of India. The CMD-linked SSR marker which is reported in the previous studies have generated eight alleles and each were regressed with CMD resistance and resulted in non-significant linkage to CMD resistance.

Spray characteristics of diesel and derivatives in direct injection diesel engines with varying injection pressures

Raghu Palani,Nallusamy Nallusamy,Pitchandi K 대한기계학회 2015 JOURNAL OF MECHANICAL SCIENCE AND TECHNOLOGY Vol.29 No.10

The combustion and emission characteristics of inedible oils and their derivatives are quite different from those of mineral diesel; inparticular, inedible oils and their derivatives present higher molecular, relative density, and vaporization characteristics. These propertiesexert great impacts on the fuel spray as well as the interactions of this spray with air in the combustion chamber. Thus, examining spraycharacteristics, including spray cone angle, spray tip penetration, spray area, and fuel atomization, is necessary. The spray characteristicsof fuel mainly depend on the fuel injection pressure, density, viscosity, ambient pressure, and temperature. Among these parameters, fuelinjection pressure significantly affects the spray structure. In this study, experiments were conducted using diesel, jatropha oil methylester, karanja oil methyl ester, and two biodiesel blended fuels (JB20 and KB20)] as fuels in a diesel engine with different injection pressures. Optical techniques for spray visualization and image processing are very efficient tools for analyzing the spray parameters of thetested fuels. Macroscopic spray properties, such as spray tip penetration, spray cone angle, and spray area, were acquired from imagescaptured by a high-speed video camera. The Sauter mean diameter and spray volume of all of the tested fuels were also estimated. Experimentalresults showed that the biodiesel blends demonstrate features different from those of diesel fuel. KB100 presented the highestspray tip penetration and spray area, followed by JB100 JB20, KB20 and diesel. Diesel fuel showed the best spray parameters, followedby JB20, KB20, KB100 and JB100. The tested fuels exhibited better spray characteristics at higher injection pressures than at lower ones.

Synthesis and Characterization of Novel Polyurethanes Based on 4-{(4-Hydroxyphenyl)iminomethyl} phenol

Raghu, A.V.,Jeong, Han-Mo,Kim, Jae-Hoon,Lee, Yu-Rok,Cho, Youn-Bok,Sirsalmath, Kiran The Polymer Society of Korea 2008 Macromolecular Research Vol.16 No.3

Four novel polyurethanes were prepared from 4-{(4-hydroxyphenyl)iminomethyl} phenol by reactions with two aromatic diisocyanates, 4,4'-diphenylmethane diisocyanate and toluene 2,4-diisocyanate, and two aliphatic diisocyanates, isophorone diisocyanate and hexamethylene diisocyanate. The polyurethanes formed were characterized by UV-vis, fluorescence, FT-IR, $^1H$-NMR, $^{13}C$-NMR, differential scanning calorimetry, thermogravimetry, and X-ray diffraction. The polymers were semi-crystalline and all polymers were soluble in polar aprotic solvents.

Tuberculosis and Respiratory Diseases : Idiopathic Pulmonary Fibrosis (IPF), A Distinct Subgroup of Idiopathic Interstitial Pneumonia (IIP): Evolving Definition And Current Concepts In Management

( Ganesh Raghu ) 대한결핵 및 호흡기학회 2001 대한결핵 및 호흡기학회 추계학술대회 초록집 Vol.93 No.0

T Lymphocytes Negatively Regulate Lymph Node Lymphatic Vessel Formation

Kataru, Raghu P.,Kim, Honsoul,Jang, Cholsoon,Choi, Dong Kyu,Koh, Bong Ihn,Kim, Minah,Gollamudi, Sudheer,Kim, Yun-Keun,Lee, Seung-Hyo,Koh, Gou Young Elsevier 2011 Immunity Vol.34 No.1

<P><B>Summary</B></P><P>Lymph node lymphatic vessels (LNLVs) serve as a conduit to drain antigens from peripheral tissues to within the lymph nodes. LNLV density is known to be positively regulated by vascular endothelial growth factors secreted by B cells, macrophages, and dendritic cells (DCs). Here, we show that LNLV formation was negatively regulated by T cells. In both steady and inflammatory states, the density of LNLVs was increased in the absence of T cells but decreased when T cells were restored. Interferon-γ secretion by T cells suppressed lymphatic-specific genes in lymphatic endothelial cells and consequently caused marked reduction in LNLV formation. When T cells were depleted, recruitment of antigen-carrying DCs to LNs was augmented, reflecting a compensatory mechanism for antigen presentation to T cells through increased LNLVs. Thus, T cells maintain the homeostatic balance of LNLV density through a negative paracrine action of interferon-γ.</P> <P><B>Graphical Abstract</B></P><P><ce:figure id='dfig1'></ce:figure></P><P><B>Highlights</B></P><P>► Lymphatic vessels (LVs) are absent in the T cell zone of lymph nodes (LNs) ► T cells reduce LNLV density by secreting IFN-<B>γ</B> ► IFN-<B>γ</B> downregulates lymphatic-specific genes ► IFN-<B>γ</B> prevents lymphangiogenesis</P>

Critical role of CD11b+ macrophages and VEGF in inflammatory lymphangiogenesis, antigen clearance, and inflammation resolution

Kataru, Raghu P.,Jung, Keehoon,Jang, Cholsoon,Yang, Hanseul,Schwendener, Reto A.,Baik, Jung Eun,Han, Seung Hyun,Alitalo, Kari,Koh, Gou Young American Society of Hematology 2009 Blood Vol.113 No.22

<P>Using a bacterial pathogen-induced acute inflammation model in the skin, we defined the roles of local lymphatic vessels and draining lymph nodes (DLNs) in antigen clearance and inflammation resolution. At the peak day of inflammation, robust expansion of lymphatic vessels and profound infiltration of CD11b+/Gr-1+ macrophages into the inflamed skin and DLN were observed. Moreover, lymph flow and inflammatory cell migration from the inflamed skin to DLNs were enhanced. Concomitantly, the expression of lymphangiogenic growth factors such as vascular endothelial growth factor C (VEGF-C), VEGF-D, and VEGF-A were significantly up-regulated in the inflamed skin, DLNs, and particularly in enriched CD11b+ macrophages from the DLNs. Depletion of macrophages, or blockade of VEGF-C/D or VEGF-A, largely attenuated these phenomena, and produced notably delayed antigen clearance and inflammation resolution. Conversely, keratin 14 (K14)-VEGF-C transgenic mice, which have dense and enlarged lymphatic vessels in the skin dermis, exhibited accelerated migration of inflammatory cells from the inflamed skin to the DLNs and faster antigen clearance and inflammation resolution. Taken together, these results indicate that VEGF-C, -D, and -A derived from the CD11b+/Gr-1+ macrophages and local inflamed tissues play a critical role in promoting antigen clearance and inflammation resolution.</P>

Starch Content and Cassava Mosaic Disease Genetic Diversity with Relation to Yield in South Indian Cassava (Manihot esculenta Crantz) Germplasm

Duraisamy, Raghu,Rathinasamy, Sakthi Ambothi,Natesan, Senthil,Muthurajan, Raveendran,Ramineni, Jana Jeevan,Karuppusamy, Nageswari,Lakshmanan, Pugalenthi,Chokkappan, Mohan,Gandhi, Karthikeyan 한국작물학회 2011 Journal of crop science and biotechnology Vol.14 No.3

Cassava, family Euphorbiaceae, is the fifth most important staple food crop. The study of variability and diversity present in diverse cassava accessions maintained at the field genebank of TCRS, TNAU is essential to design the breeding program of cassava in TNAU. Hence, a study was carried out to assess the genetic diversity based on morphological traits and Simple Sequence Repeat (SSR) markers, identifying the SSR markers linked to a cassava mosaic disease-resistant QTL region. Genetic diversity among cassava germplasm accessions was estimated using 28 morphological traits and three SSR markers. The polymorphic information content (PIC) result gives high information for all the SSR markers. Morphological traits revealed 10 clusters and the SSR markers revealed 13 clusters at a similarity coefficient of 2.514 and 0.75, respectively. The SSR marker diversity revealed that the most promising clusters (II and XII) possessing accessions with yield attributing traits and cluster IX were grouped together due to low yield and CMD susceptibility. Morphological descriptors revealed variance for yield contributing traits. The first three principle components accounted for 10.8, 9.1, and 8.4%, respectively. Correlation studies showed significant correlation among yield and yield-attributing traits, which in turn influences yield. The morphological traits diversity reveals that cluster VI was the most promising cluster in which genotypes ME209 and ME460 possess higher yield and starch content with cassava mosaic disease (CMD) resistance. Most of the accessions grouped under cluster X belong to selection from International Centre for Tropical Agriculture (CIAT) collections and the cultivars under clusters I and II were true cassava seed (TCS) selections of India. The CMD-linked SSR marker which is reported in the previous studies have generated eight alleles and each were regressed with CMD resistance and resulted in non-significant linkage to CMD resistance

(Invited) Electrodeposited CIS and CIGS-based Solar Cells

Bhattacharya, Raghu N,Kim, Youngho,Yoon, Sanghyo,Jeon, Myoungae The Electrochemical Society 2013 ECS transactions Vol.50 No.40

<P>Previously, we reported 15.4%-efficient copper indium gallium diselenide (CIGS)-based photovoltaic devices from electrodeposited precursor films in which the final film composition was adjusted using the physical vapor deposition (PVD) method. At present, we are fabricating CIS and CIGS-based solar cells directly from electrodeposited precursor films, eliminating the expensive PVD step. Electrodeposited CIS and CIGS absorber layers are fabricated from stacked Cu/In and Cu/In/Ga layers, respectively. All films are electrodeposited from aqueous-based solutions at room temperature in a two-electrode cell configuration, with platinum gauze as the counter electrode and a glass substrate as the working electrode. The substrate is DC-sputtered with about 1 µm of Mo. The electrodeposited films are selenized at high temperature (~550ºC) to obtain 10.9%-efficient CIS device and 11.7%-efficient CIGS device.</P>

Synthesis and Biological Evaluation of Some Novel [4-(1H-Benzoimidazol-2-yl)-thiazol-2-yl]-benzylidene-amines and N-[4-(1H-Benzoimidazol-2-yl)-thiazol-2-yl]-N'-benzylidene-hydrazines

Mekala, Raghu Vardhan Reddy,Danda, Ravinder Reddy,Gadegoni, Hemalatha Korean Chemical Society 2013 대한화학회지 Vol.57 No.1

A new family of thiazole heterocycles, namely [4-(1H-benzoimidazol-2-yl)-thiazol-2-yl]-benzylidene-amines has been synthesized by the condensation of 4-(1H-Benzoimidazol-2-yl)-thiazol-2-ylamine with various aromatic aldehydes and N-[4-(1H-benzoimidazol-2-yl)-thiazol-2-yl]-N'-benzylidene-hydrazines through the cyclization of 1-(1H-benzoimidazol-2-yl)-2-bromo-ethanone with arylthiosemicarbazones. The target compounds are achieved by using 1-(1H-Benzoimidazol-2-yl)-ethanone as starting material. The chemical structures of all newly synthesized compounds were confirmed by their IR, $^1H$ NMR and Mass spectral data. Further the compounds were used to evaluate their antimicrobial activity and found that the appreciable antimicrobial activity by some of the title compounds.