n-th power signed graphs

Siva Kota Reddy,Vijay,Lokesha 장전수학회 2009 Proceedings of the Jangjeon mathematical society Vol.12 No.3

A signed graph (marked graph) is an ordered pair S = (G, σ) (S = (G, μ)), where G = (V,E) is a graph called the underlying graph of S and σ : E → {+, −} (μ : V → {+, −}) is a function. The n-th power graph of a graph G = (V,E) is a graph Gn = (V,E'), with same vertex set as G, and has two vertices u and v are adjacent if their distance in G is n or less. Analogously, one can define the nth power signed graph of a signed graph S = (G, σ). Consider the marking μ on vertices of S defined as follows: each vertex v ∈ V , μ(v) is the product of the signs on the edges incident at v. The nth power signed graph of S is a signed graph Sn = (Gn, σ') where Gn is the underlying graph of Sn, where for any edge e = uv 2 Gn, 0(uv) = μ(u)μ(v). It is shown that for any signed graph S, its nth power signed graph Sn is balanced. We then give structural characterization of n-th power signed graphs. Two signed graphs S1 and S2 are switiching equivalent written S1 ~ S2, whenever there exists a marking μ of S1 such that the signed graph Sμ(S1) obtained by changing the sign of every edge of S1 to its opposite whenever its end vertices are of opposite signs, is isomorphic to S2. Further, we present solutions of some signed graph switching equations involving the line signed graph, complement and n-th power signed graph operations. One such equation (L(S))n ~ S generalizes a result of P. Siva Kota Reddy and M. S. Subramanya (L(S) ~ S) [11].

A Brief Review on Recent Developments in MAPbI3 Perovskite-Based Transistors

Siva Parvathi Padi,김태용,라벨로 마테우스,이준신 한국전기전자재료학회 2021 전기전자재료학회논문지 Vol.34 No.5

Field-effect transistors (FETs) are the key elements of conventional electronics; hence, have drawn a lot of research and commercial interests. In recent years, metal halide perovskite materials have achieved a remarkable efficiency of 29.15% in the field of photovoltaics, and have drawn the scientific community’s attention to promote their use in the field of optoelectronics, such as FETs and phototransistors. The MAPbI3 (methylammonium lead iodide) perovskite TFT has achieved a record hole mobility of 21.41 cm2/V-s in the year 2020. In this review, we will briefly discuss the physical structure of MAPbI3 perovskite and the essential factors that stimulate these devices, together with the role of defects, the ion migration concept, and the implication of both dielectric and electrode materials on the device’s performance.

Simulations for the flow of viscoplastic fluids in a cavity driven by the movement of walls by Lattice Boltzmann Method

Siva Subrahmanyam Mendu,Prasanta Kumar Das 한국유변학회 2020 Korea-Australia rheology journal Vol.32 No.3

The current paper is focused on analyzing the flow of viscoplastic fluid in a cavity that is driven by the two walls. The Lattice Boltzmann method (LBM) is used to solve the discrete Boltzmann equation. To represent the stress-strain rate relationship of viscoplastic fluids, the Bingham Papanastasiou constitutive model is considered. Cavity flow filled with Bingham fluids is considered for validating the present LBM code. After successful validation of the code, the analysis is extended for three dissimilar wall motions- simultaneous and opposed movement of the parallel facing walls, and the simultaneous motion of non-facing walls. The flow dynamics of Bingham fluid is influenced by Reynolds and Bingham numbers which can be studied using velocity and streamline plots. Subsequently, the yielded and un-yielded zones in a cavity have been effectively tracked using the limiting condition of yield stress. Further, the effect of wall motion on the variation of those zones inside a cavity has been studied. Finally, the drag coefficient for considered wall motions is presented.

Effects on Direct-to-Consumer Advertising of Prescription Drugs in Singapore: The Moderating Role of Low Credibility

Siva Muthaly,하홍열,Jing Ping Yeo,김남윤 한국외국어대학교 국제지역연구센터 2009 International Area Studies Review Vol.12 No.2

As consumer beliefs about direct-to-consumer (“DTC’) advertising vary, two different types of beliefs (beliefs about DTC advertising and beliefs about quality of treatment) are associated with how consumers’ beliefs affect behavioral intentions. The authors also consider how consumers’ judgments of DTC advertising of prescription drugs vary with different levels of credibility. Taking a moderating effect perspective on the consumer beliefs-behavioral intentions formation, the authors theorize that the lower level of credibility is a key element in facilitating consumer activity. Data from Singaporean had been used to test a proposed model. The findings show that the effect of beliefs about quality of prescription drugs advertised on behavioral intention is more powerful than the effect of beliefs about DTC advertising. The interaction effects suggest that at a lower level of credibility on DTC advertising, consumers are likely to discuss this matter with their doctors to increase their confidence.

Resistance Spot Welding of GI/Al/SS three ply clad sheet

Siva Prasad Murugan,Murali Mohan Cheepu,Dae-Geun Nam,Yeong-Do park 대한용접·접합학회 2016 대한용접학회 특별강연 및 학술발표대회 개요집 Vol.2016 No.4

Overexpressed CYP450 mediated apoptosis evaluates cytotoxicity and teratotoxicity of Cucumis callosus

Siva Prasad Panda,Bikash Ranjan Jena,Gade Kalyani,Uttam Prasad Panigrahy 경희대학교 융합한의과학연구소 2018 Oriental Pharmacy and Experimental Medicine Vol.18 No.4

Fruits of Cucumis callosus (Rottl.) Cogn. (Family: Cucurbitaceae) plant, are commonly known as “bitter cucumber” (English) and “Kachri” (Hindi) in India and have been traditionally used for antioxidant, rich source of vitamin C, antidiabetic and anticancer actions. Tribal peoples of Odissa and West-Bengal are using these fruits during worship and as a vegetable. In vitro cytotoxicity of methanolic seed extract of C. callosus (MSCC) at different concentrations (25, 50, 100, 200, 400) μg/ ml and methanolic pericarp extract of C. callosus (MPCC) at (30, 60, 120, 240, 360) μg/ml on Ehrlich Ascites Carcinoma (EAC) cell line, has been evaluated by using the MTT [3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide] assay and Trypan blue dye exclusion assay for a period of 3 h treatment. Acute toxicity and in vivo teratotoxicity of both extracts were also evaluated using the Zebrafish embryo developmental assay. The MSCC and MPCC showed the direct cytotoxic effect on EAC cells in a dose-dependent manner with IG50 value 273.17 and 235.08 μg/ml respectively. The MPCC in 240 and 360 μg/ml showed a strong teratotoxic effect on Zebrafish embryo in a dose-dependent manner. The cytotoxicity and teratotoxicity of MPCC were due to overexpressed CYP450 mediated apoptosis in μthe tissue.

Human Adipose Tissue Derivatives as a Potent Native Biomaterial for Tissue Regenerative Therapies

Siva Sankari Sharath,Janarthanan Ramu,Shantikumar Vasudevan Nair,Subramaniya Iyer,Ullas Mony,Jayakumar Rangasamy 한국조직공학과 재생의학회 2020 조직공학과 재생의학 Vol.17 No.2

Background: Human adipose tissue is a great source of translatable biomaterials owing to its ease of availability and simple processing. Reusing discardable adipose tissue for tissue regeneration helps in mimicking the exact native microenvironment of tissue. Over the past 10 years, extraction, processing, tuning and fabrication of adipose tissue have grabbed the attention owing to their native therapeutic and regenerative potential. The present work gives the overview of next generation biomaterials derived from human adipose tissue and their development with clinical relevance. Methods: Around 300 articles have been reviewed to widen the knowledge on the isolation, characterization techniques and medical applications of human adipose tissue and its derivatives from bench to bedside. The prospective applications of adipose tissue derivatives like autologous fat graft, stromal vascular fraction, stem cells, preadipocyte, adipokines and extracellular matrix, their behavioural mechanism, rational property of providing native bioenvironment, circumventing their translational abilities, recent advances in featuring them clinically have been reviewed extensively to reveal the dormant side of human adipose tissue. Results: Basic understanding about the molecular and structural aspect of human adipose tissue is necessary to employ it constructively. This review has nailed the productive usage of human adipose tissue, in a stepwise manner from exploring the methods of extracting derivatives, concerns during processing and its formulations to turning them into functional biomaterials. Their performance as functional biomaterials for skin regeneration, wound healing, soft tissue defects, stem cell and other regenerative therapies under in vitro and in vivo conditions emphasizes the translational efficiency of adipose tissue derivatives. Conclusion: In the recent years, research interest has inclination towards constructive tissue engineering and regenerative therapies. Unravelling the maximum utilization of human adipose tissue derivatives paves a way for improving existing tissue regeneration and cellular based therapies and other biomedical applications.

Advancements in temporomandibular joint total joint replacements (TMJR)

Siva Kumar Mamidi,Klutcharch,Shradha Rao,Julio C. M. Souza,Louis G. Mercuri,Mathew T. Mathew 대한의용생체공학회 2019 Biomedical Engineering Letters (BMEL) Vol.9 No.2

The goal of this paper is to review the advantages and disadvantages of the various treatment options of temporomandibularjoint (TMJ) total joint replacement (TJR). TMJ articles published within the last 20 years were reviewed to collect the informationon non-invasive and invasive TMD treatment methods. Recent technological advancements helped the evolution oftreatment methods and off ered signifi cant value to TMD patients and surgeons. Considering the TMD levels, the therapeuticprocedures can involve general health examiniations, physical therapy, medication, oral rehabilation or as an end stage clinicalinvention, temporomandibular joint replacement. In fact when intra-articular TMD is present, the eff ective treatmentmethod appears to be TJR. However, concern for infection, material hypersensitivity, device longevity and screws looseningissues still exists. Further combined research utilizing the knowledge and expertise of, surgeons, material scientists, andbioengineers is needed for the development of improved TMD therapeutic treatment.

Estimating the AUC of the MROC curve in the presence of measurement errors

Siva G,Vishnu Vardhan R 한국통계학회 2022 Communications for statistical applications and me Vol.29 No.5

Collection of data on several variables, especially in the field of medicine, results in the problem of measurement errors. The presence of such measurement errors may influence the outcomes or estimates of the parameter in the model. In classification scenario, the presence of measurement errors will affect the intrinsic cum summary measures of Receiver Operating Characteristic (ROC) curve. In the context of ROC curve, only a few researchers have attempted to study the problem of measurement errors in estimating the area under their respective ROC curves in the framework of univariate setup. In this paper, we work on the estimation of area under the multivariate ROC curve in the presence of measurement errors. The proposed work is supported with a real dataset and simulation studies. Results show that the proposed bias-corrected estimator helps in correcting the AUC with minimum bias and minimum mean square error.

Particulate Reinforcements in Dicyanate Composites with Nanoporous Aluminum Fumarate as Reactive Filler: Thermal Properties

Siva Kaylasa Sundari Saravanamuthu,Shamim Rishwana Syed Mohammed,Ramani Ramasubbu,Arunjunai Raj Mahendran,Vijayakumar Chinnaswamy Thangavel 한국고분자학회 2022 폴리머 Vol.46 No.4

In this work, the synthesized nanoporous aluminum fumarate (Al_FA_A) metal organic framework (MOF) hasbeen used as reactive filler for the bisphenol-A dicyanate (BADCy) resin system. The use of Al_FA_A is interesting dueto the involvement of double bonds (fumarate) in triazine during polymerization. The thermal properties of the polymersformed with and without reactive filler were evaluated under different curing temperatures, prepolymerizations and postpolymerizations conditions. All the samples were characterized by Fourier transform infrared spectroscopy (FTIR), thermogravimetric analysis (TGA), differential scanning calorimetry (DSC) and X-ray diffraction analysis (XRD) andEvolved gas analysis. On the contrary, the cure chemistry was determined by non-isothermal model free kinetic methods. This study provides a new path to utilize the MOFs as reactive nanoparticle fillers to obtain multifunctional materials.