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A discrete Cosine Adaptive Harmonic Wavelet Packet and Its Application to Signal Compression

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Journal of Signal and Information Processing 2010年第1期1卷 63-76页

作者： Nandini Basumallick S. V. narasimhan 不详

A new adaptive Packet algorithm based on discrete Cosine harmonic wavelet transform (dCHWT), (dCAHWP) has been proposed. This is realized by the discrete Cosine Harmonic Wavelet transform (dCHTWT) which exploits the good properties of dCT viz., energy compaction (low leakage), frequency resolution and computational simplicity due its real nature, compared to those of dFT and its harmonic wavelet version. Hence the proposed wavelet packet is advantageous both in terms of performance and computational efficiency compared to those of existing dFT harmonic wavelet packet. Further, the new dCAHWP also enjoys the desirable properties of a Harmonic wavelet transform over the time domain WT, viz., built in decimation without any explicit antialiasing filtering and easy interpolation by mere concatenation of different scales in frequency (dCT) domain with out any image rejection filter and with out laborious delay compensation required. Further, the compression by the proposed dCAHWP is much better compared to that by adaptive WP based on daubechies-2 wavelet (dBAWP). For a compression factor (CF) of 1/8, the ratio of the percentage error energy by proposed dCAHWP to that by dBAWP is about 1/8 and 1/5 for considered 1-d signal and speech signal, respectively. Its compression performance is better than that of dCHWT, both for 1-d and 2-d signals. The improvement is more significant for signals with abrupt changes or images with rapid variations (textures). For compression factor of 1/8, the ratio of the percentage error energy by dCAHWP to that by dCHWT, is about 1/3 and 1/2, for the considered 1-d signal and speech signal, respectively. This factor for an image considered is 2/3 and in particular for a textural image it is 1/5.

关键词： Adaptive Harmonic Wavelet Packets discrete Cosine Transform Signal Compression

Engine valve and seat insert wear study with a simulator

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Science China Mathematics 2001年第S1期44卷 235-241页

作者： Y.S.Wang S.narasimhan Eaton Corp. Engine Components Operations 19218 B Drive SouthMarshall MI 49068

The demands on higher performance and the increasing use of alternative fuels chal-lenge engine valves now with greater wear problems than before. A seat wear simulator was builtto evaluate the compatibility and wear of valve and seat insert. The rig test results have been suc-cessfully correlated with engine test results. In this study, intake valves made from Sil 1 materialwere treated with salt bath nitride processes and tested against six different insert materials. Wearresistance of these combinations was ranked and compared to the Sil 1 valve without *** test results demonstrate that nitriding improved valve seat wear resistance. In the total valveseat recession ranking, the combination of nitrided Sil 1 valve against T 400 insert exhibited theleast total recession among the nineteen combinations of valve and insert tested. The results indi-cate that the valve seat wear mechanisms are a complex combination of adhesion and shearstrain. The nitrides in the compound layer of nitrided valves gave strong atomic bonding, higherhardness, compressive residual stresses, and possible low friction, thus resulted in the superiorwear performance.

关键词： engine valve nitride seat insert valve scat wear mechanism wear simulation

A dual Tree Complex discrete Cosine Harmonic Wavelet Transform (AdCHWT) and Its Application to Signal/Image denoising

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Journal of Signal and Information Processing 2011年第3期2卷 218-226页

作者： M. Shivamurti S. V. narasimhan 不详

A new simple and efficient dual tree analytic wavelet transform based on discrete Cosine Harmonic Wavelet Transform dCHWT (AdCHWT) has been proposed and is applied for signal and image denoising. The analytic dCHWT has been realized by applying dCHWT to the original signal and its Hilbert transform. The shift invariance and the envelope extraction properties of the AdCHWT have been found to be very effective in denoising speech and image signals, compared to that of dCHWT.

关键词： Analytic discrete Cosine Harmonic Wavelet Transform Analytic Wavelet Transform dual Tree Complex Wavelet Transform dCT Shift Invariant Wavelet Transform Wavelet Transform denoising

Chemopreventive effect of apple and berry fruits against colon cancer

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World Journal of Gastroenterology 2014年第45期20卷 17029-17036页

作者： Saravana Kumar Jaganathan Muthu Vignesh Vellayappan Gayathri narasimhan Eko Supriyanto dyah Ekashanti Octorina dewi Aqilah Leela T Narayanan Arunpandian Balaji Aruna Priyadarshini Subramanian Mustafa Yusof IJN-UTM Cardiovascular Engineering Centre Faculty of Bioscience and Medical Engineering Universiti Teknologi Malaysia department of Research and development PSNA College of Engineering and Technology department of Pharmacology

Colon cancer arises due to the conversion of precancerous polyps(benign)found in the inner lining of the *** is better than cure,and this is very true with respect to colon *** epidemiologic studies have linked colorectal cancer with food *** and berry juices are widely consumed among various ethnicities because of their nutritious *** this review article,chemopreventive effects of these fruit juices against colon cancer are *** dealing with bioavailability,in vitro and in vivo effects of apple and berry juices are emphasized in this article.A thorough literature survey indicated that various phenolic phytochemicals present in these fruit juices have the innate potential to inhibit colon cancer cell *** review proposes the need for more preclinical evidence for the effects of fruit juices against different colon cancer cells,and also strives to facilitate clinical studies using these juices in humans in large *** conclusion of the review is that these apple and berry juices will be possible candidates in the campaign against colon cancer.

关键词： Apple Berry Chemoprevention Colon cancer Fruit juices Phytochemicals

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在分布式数据库系统中的数据库分配

计算机工程与应用 1991年第5期27卷 190-201页

作者： S.Ram S.narasimhan 项明峰中国人民大学信息系

我们的研究工作中心是开发一种设计分布式数据库的方法。用这种方法把数据库分配到由通讯网络联接起来的众多计算机场地上。它考虑数据库使用的方式、网络中的通讯代价、对数据请求进行排队处理而产生的延迟、为维护数据库各种副本的一... 详细信息

我们的研究工作中心是开发一种设计分布式数据库的方法。用这种方法把数据库分配到由通讯网络联接起来的众多计算机场地上。它考虑数据库使用的方式、网络中的通讯代价、对数据请求进行排队处理而产生的延迟、为维护数据库各种副本的一致性所花费的代价、以及数据库的存贮代价。这种方法是基于非线性整数规划模型的,它利用一种使用分解方法的拉格朗日松弛过程来导出问题的近似最优解。现已建立起一种工具来使用这种方法、模型和松弛过程。我们所开发的这种方法对数据库领域是很有意义的,因为它是第一个在数据库分配问题上考虑通讯代价,维护一致性的代价和排队延迟的。它适用于广泛的、正在从集中的计算机环境变化到分布式计算机环境的组织机构。

关键词：分布式数据库分配

Pediatric Nd:YAG laser capsulotomy in the operating room: review of 87 cases

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International Journal of Ophthalmology(English edition) 2019年第5期12卷 779-783页

作者： Michael Kinori narasimhan Jagannathan Anne M Langguth Marjorie A Sasso Marilyn B Mets Bahram Rahmani Hawke Yoon Rebecca Mets-Halgrimson Sudhi P Kurup Janice L Zeid The Goldschleger Eye Institute Sheba Medical CenterTel Ha ShomerAffiliated to the Sackler Faculty of MedicineTel Aviv University department of Pediatric Anesthesiology Ann & Robert H.Lurie Children's Hospital of Chicago division of Ophthalmology Ann & Robert H.Lurie Children's Hospital of Chicago department of Ophthalmology Northwestern University Feinberg School of Medicine department of Surgical Services Ann & Robert H.Lurie Children's Hospital of Chicago

AIM: To report a large series of children having Nd:YAG laser capsulotomy in the operating room using the lateral decubitus position. METHOdS: Medical records of children who underwent Nd:YAG laser capsulotomy in the operating room at Ann & Robert H. Lurie Children's Hospital of Chicago between September 2008 and April 2017 were reviewed. Induction of general anesthesia and intubation was performed in the supine position after which the patient was placed in lateral decubitus position. The Nd:YAG laser capsulotomy was performed using a standard protocol. At the completion of the procedure, the patient was turned back into the supine position and extubated. RESULTS: This study included 87 eyes of 60 patients. Patient's age ranged from 1 to 18 y(mean 6.4±4.1 y). In most cases(84/87, 97%), the procedure was performed under general anesthesia. In all cases, good focus on the membrane was achieved, and the procedure was performed successfully. There were no intraoperative ocular or anesthesia-related complications. CONCLUSION: When performing Nd:YAG laser capsulotomy in the operating room, the lateral decubitus position allowsan easy and safe approach without the risk of potentially devastating complications that have been associated with the previously described sitting and prone positions.

关键词： posterior capsular opacification YAG capsulotomy general anesthesia pediatric cataract

Astrocytes Prevent Ethanol Induced Apoptosis of Nrf2 depleted Neurons by Maintaining GSH Homeostasis

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Open Journal of Apoptosis 2012年第2期1卷 9-18页

作者： Madhusudhanan narasimhan Marylatha Rathinam dhyanesh Patel George Henderson Lenin Mahimainathan department of Pharmacology and Neuroscience Texas Tech University Health Sciences Center Lubbock USA South Plains Alcohol and Addiction Research Center Texas Tech University Health Sciences Center Lubbock USA

Glutathione (GSH), a major cellular antioxidant protects cells against oxidative stress injury. Nuclear factor erythroid 2-related factor 2 (NFE2L2/Nrf2) is a redox sensitive master regulator of battery of antioxidant enzymes including those involved in GSH antioxidant machinery. Earlier we reported that ethanol (ETOH) elicits apoptotic death of pri-mary cortical neurons (PCNs) which in partly due to depletion of intracellular GSH levels. Further a recent report from our laboratory illustrated that ETOH exacerbated the dysregulation of GSH and caspase mediated cell death of pure cortical neurons that are compromised in Nrf2 machinery (narasimhan et al., 2011). In various experimental models of neurodegeneration, neuronal antioxidant defenses mainly GSH has been shown to be supported by astrocytes. We therefore sought to determine whether astrocytes can render protection to neurons against ETOH toxicity, particularly when the function of Nrf2 is compromised in neurons. The experimental model consisted of co-culturing PCAs with Nrf2 downregulated PCNs that were exposed with and without 4 mg/mL ETOH for 24 h. Monochlorobimane (MCB) staining followed by FACS analysis showed that astrocytes blocked ETOH induced GSH decrement in Nrf2-silenced neurons as opposed to exaggerated GSH depletion in Nrf2 downregulated PCNs alone. Similarly, the heightened activa-tion of caspase 3/7 observed in Nrf2-compromised neurons was attenuated when co-cultured with astrocytes as meas-ured by luminescence based caspase Glo assay. Furthermore, annexin-V-FITC staining followed by FACS analysis re-vealed that Nrf2 depleted neurons showed resistance to ETOH induced neuronal apoptosis when co-cultured with as-trocytes. Thus, the current study identifies ETOH induced dysregulation of GSH and associated apoptotic events ob-served in Nrf2-depleted neurons can be blocked by astrocytes. Further our results suggest that this neuroprotective ef-fect of astrocyte despite dysfunctional Nrf2 system in neu

关键词： Astrocyte-Neuron Co-Culture Nrf2 Ethanol Oxidative Stress GSH

The Art and Science of Cardiac Physical Examination: With Heart Sounds and Pulse Wave Forms on Cd 1

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丛书名： Contemporary Cardiology

2006年

作者： narasimhan Ranganathan Vahe Sivaciyan Franklin B. Saksena

ISBN: (纸本)9781588297761

A panel of academic clinicians brings the art and science of the clinical cardiac examination to the bedside with a tour de force tutorial on the techniques needed to elicit various physical signs and to interpret them in relation to the patient's symptoms and underlying cardiac condition. drawing on twenty-five years of teaching and training physicians and physicians-to-be, the authors integrate the physiology, pathophysiology, and mechanisms behind the various physical signs with a thorough and easy-to-use practical approach that makes physician feel more comfortable and competent performing the cardiac physical examination. The authors pay particular attention to the interpretation of the jugular venous pulsations and contour and make the physiology and pathophysiology of the normal and abnormal arterial pulse interesting and relevant. A unique and original companion video Cd presents close to 140 clinical examples taken from actual patients, complete with audio recordings of various heart sounds and murmurs displayed in real time as seen on an oscilloscope. Additional video recordings show both precordial pulsations and jugular pulsations from patients with a variety of cardiac lesions, and illustrate certain unusual clinical conditions through simultaneous echocardiographic images and recordings of heart sounds and murmurs

关键词： Heart diseases

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印度靛蓝航空卓越的基础服务战略

新营销 2013年第2期15卷 14-15页

作者： Prasad.narasimhan

印度靛蓝航空（IndiGo）6年前成立，但是现在它在印度廉价航空细分市场上已经上升到首位，占有最大的市场份额，而且是细分市场上唯一盈利的航空公司。然而，成立之初，没有太多人对它抱有太大的希望。人们想，这样的服务是不是太基础... 详细信息

印度靛蓝航空（IndiGo）6年前成立，但是现在它在印度廉价航空细分市场上已经上升到首位，占有最大的市场份额，而且是细分市场上唯一盈利的航空公司。然而，成立之初，没有太多人对它抱有太大的希望。人们想，这样的服务是不是太基础了？它如何突出自已的差异化优势？

关键词：廉价航空服务战略印度细分市场差异化优势市场份额航空公司