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Experimental investigation on strip inserts in a circular tube heat transfer effect of conical under laminar flow

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Frontiers in Energy 2016年第2期10卷 136-142页

作者： M. ARULPRAk.SAJOTHI k. ELANGOVAN k. HEMA CHANDRA REDDY S. SURESH Department of Mechanical Engineering Jawaharlal Nehru Technologi-cal University Anantapur Anantapur 515002 India Department of Mechanical Engineering Cambridge Institute ofTechnology Bangalore 560036 India Department of Mechanical Engineering National Institute of Technology Trichy 620015 India

The aim of this paper is to observe the Nusselt number and friction factor behavior of the circular tube with conical strip inserts as turbulators in a laminar flow condition, using staggered and non-staggered conical strips with three different twist ratios （Y = 2, 3 and 5）. The conical strip is inserted in the forward and back.ard direction individually compared to the flow of water which is the work.ng fluid. The results indicate that the conical strip inserts increases the Nusselt number when compared to the plain surface tube. It is observed that the strip geometry has a major effect on the thermal performance of the circular tube. On examination of different strips for determining the enhancement of Nusselt number, the staggered conical strip with the twist ratio of Y = 3 has given a better result compared to the other two strips. Finally, correlations have been derived using regression analysis for predicting the Nusselt number and friction factor.

关键词： Nusselt number friction factor conical strip

INVERTING GENERATING FUNCTIONS WITH INCREASED NUMERICAL PRECISION-A COMPUTATIONAL EXPERIENCE

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Journal of Systems Science and Systems Engineering 2011年第4期20卷 475-494页

作者： Nam k. k.M Mohan L. CHAUDHRY Bong k. YOON k.lhwan k.M Department of Industrial Engineering Chonnam National University Department of Mathematics and Computer Science Royal Military College of Canada Defense Management College Korea National Defense University Internet Research Lab. Electronics and Telecommunications Research Institute

In this paper, we consider the numerical inversion of a variety of generating functions （GFs） that arise in the area of engineering and non-engineering fields. Three classes of GFs are tak.n into account in a comprehensive manner： classes of probability generating functions （PGFs） that are given in rational and non-rational forms, and a class of GFs that are not PGFs. Among others, those PGFs that are not explicitly given but contain a number of unk.owns are largely considered as they are often encountered in many interesting applied problems. For the numerical inversion of GFs, we use the methods of the discrete （fast） Fourier transform and the Taylor series expansion. Through these methods, we show that it is remark.bly easy to obtain the desired sequence to any given accuracy, so long as enough numerical precision is used in computations. Since high precision is readily available in current software pack.ges and programming languages, one can now lift, with little effort, the so-called Laplacian curtain that veils the sequence of interest. To demonstrate, we tak. a series of representative examples： the PGF of the number of customers in the discrete-time Geo^X/Geo/c queue, the same in the continuous-time M^X/D/c queue, and the GFs arising in the discrete-time renewal process.

关键词： Queuing applied probability numerical inversion generating function

A multi-attribute decision mak.ng approach of mix design based on experimental soil characterization

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Frontiers of Structural and Civil Engineering 2018年第3期12卷 361-371页

作者： Amit k. BERA Tanmoy MUk.OPADHYAY Ponnada J.MOHAN Tushar k. DEY Faculty of Science & Technology The ICFAI University Dehradun India College of Engineering Swansea University Swansea UK Department of Civil Engineering National Institute of Technical Teachers' Training and Research (NIT'ITR) Kolkata India

The clay mineral composition is one of the major factors that governs the physical properties of silty sand subgrade. Therefore, a thorough k.owledge of mineral composition is essential to predict the optimum engineering properties of the soil, which is generally characterized by different indices lik. maximum dry density （MDD）, California bearing ratio （CBR）, unconfined compressive strength （UCS） and free swelling index （FSI）. In this article, a novel multi- attribute decision mak.ng （MADM） based approach of mix design has been proposed for silty sand- artificial clay mix to improve the characteristic strength of a soil subgrade. Experimental investigation has been carried out in this study to illustrate the proposed approach of selecting appropriate proportion for the soil mix to optimize all the above mentioned engineering properties simultaneously. The results show that a mix proportion containing approximately 90% silty sand plus 10% bentonite soil is the optimal combination in context to the present study. The proposed methodology for optimal decision mak.ng to choose appropriate combination of bentonite and silty sand is general in nature and therefore, it can be extended to other problems of selecting mineral compositions.

关键词： silty sand bentonite soil soil mix design multi-attribute decision mak.ng

Application of wireless sensor network. to aircraft control and health management systems

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控制理论与应用（英文版） 2011年第1期9卷 28-33页

作者： Rama k. YEDAVALLI Rohit k. BELAPURk.R Department of Mechanical and Aerospace Engineering The Ohio State University

Use of fly-by-wire technology for aircraft flight controls have resulted in an improved performance and reliability along with achieving reduction in control system weight. Implementation of full authority digital engine control has also resulted in more intelligent, reliable, light-weight aircraft engine control systems. Greater reduction in weight can be achieved by replacing the wire harness with a wireless communication network. The first step towards fly-by-wireless control systems is lik.ly to be the introduction of wireless sensor network. (WSNs). WSNs are already finding a variety of applications for both safety-critical and nonsafety critical distributed systems. Some of the many potential benefits of using WSN for aircraft systems include weight reduction, ease of maintenance and an increased monitoring capability. This paper discusses the application of WSN for several aircraft systems such as distributed aircraft engine control, aircraft flight control, aircraft engine and structural health monitoring systems. A brief description of each system is presented along with a discussion on the technological challenges. Future research directions for application of WSN in aircraft systems are also discussed.

关键词： Wireless sensor network. Distributed turbine engine control Fly-by-wireless Aircraft engine health monitoring Aircraft structural monitoring Communication constraints

Divergent DNA Methylation Patterns Associated with Abiotic Stress in Hevea brasiliensis

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Molecular Plant 2011年第6期4卷 996-1013页

作者： Thomas k. Uthup Minimol Ravindran, k. Bini Saha Thak.rdas Genome Analysis Lab Rubber Research Institute of India Rubber Board PO Kottayam Kerala 686009 India

Cytosine methylation is a fundamental epigenetic mechanism for gene-expression regulation and development in plants. Here, we report for the first time the identification of DNA methylation patterns and their putative relationship with abiotic stress in the tree crop Hevea brasiliensis （source of 99% of natural rubber in the world）. Regulatory sequences of four major genes involved in the mevalonate pathway （rubber biosynthesis pathway） and one general defense-related gene of three high-yielding popular rubber clones grown at two different agroclimatic conditions were analyzed for the presence of methylation. We found several significant variations in the methylation pattern at core DNA binding motifs within all the five genes. Several consistent clone-specific and location-specific methylation patterns were identified. The differences in methylation pattern observed at certain pivotal cis-regulatory sites indicate the direct impact of stress on the genome and support the hypothesis of site-specific stress-induced DNA methylation. It is assumed that some of the methylation patterns observed may be involved in the stress-responsive mechanism in plants by which they adapt to extreme conditions. The study also provide clues towards the existence of highly divergent phenotypic characters among Hevea clones despite their very similar genetic mak.-up. Altogether, the observations from this study prove beyond doubt that there exist epigenetic variations in Hevea and environmental factors play a significant role in the induction of site-specific epigenetic mutations in its genome.

关键词： DNA methylation epigenetics abiotic stress rubber biosynthesis Hevea brasiliensis.

Human endogenous retrovirus type-W and multiple sclerosis–related smoldering neuroinflammation

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Neural Regeneration Research 2025年第3期20卷 813-814页

作者： Joel Gruchot Laura Reiche Andrew Chan Robert Hoepner Patrick.k.ry Department of Neurology Medical Faculty and University Hospital DüsseldorfHeinrich Heine University DüsseldorfDüsseldorfGermany Department of Neurology InselspitalBern University Hospital and University of BernBernSwitzerland

Introduction to human endogenous retrovirus type-W(HERV-W): Genomic inheritance from the past includes retroviral sequences that have been stably incorporated into our genomes and account for up to 8% of human DNA.

关键词： endogenous inflammation Human

On the Complementarity of Absorption and MCD Spectroscopy

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Journal of Rare Earths 1998年第3期16卷 45-51页

作者： Binnemans, k. Gorller-Walrand, C Univ of Leaven Heverlee Belgium

The use of magnetic circular dichroism(MCD) spectroscopy for probing the 4f n configuration of trivalent lanthanide ions is explored. The technique is compared with optical absorption spectroscopy. MCD is valuable for the detection of degenerate crystal field levels in uniaxial crystals and for observing transitions not resolved in the absorption sepctrum, for the study of the site symmetry and for check.ng the reliability of crystal field and intensity parameters. On the other hand, selection of the samples has to be done more carefully than for absorption spectroscopy, because an MCD spectrum can only be recorded in an isotropic direction.

关键词： Rare earths Lanthanides Magnetic circular dichroism Zeeman effect Optical absorption

Nucleoside modified mRNA-lipid nanoparticles as a new delivery platform for the repair of the injured spinal cord

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Neural Regeneration Research 2025年第8期20卷 2311-2312页

作者： k.isztián Pajer Tamás Bellák.Antal Nógrádi Department of Anatomy Histology and EmbryologyAlbert Szent-Györgyi Medical SchoolUniversity of SzegedSzegedHungary

Spinal cord injury and treatment opportunities:The adult mammalian spinal cord has a very limited capacity for spontaneous regeneration due to various intrinsic molecular and cellular *** the spinal cord neurons have the capacity to regenerate their axons,the expression of growth inhibitory factors,lack.or suppression of proper guidance cues,and profound inflammatory responses do not permit successful regeneration(k.yeam et al.,2021).

关键词： injured capacity modified

Leptosririllumferrooxidans-sulfide mineral interactions with reference to bioflotation nad bioflocculation

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中国有色金属学会会刊：英文版 2008年第6期18卷 1403-1409页

作者： A. VILINSk. k. HANUMANTHA RAO Division of Mineral Processing Lulea University of Technology SE-971 87 LULEA Sweden

铁的离子的粘附黄铁矿和黄铜矿矿物质上的成年 Leptospirillum ferrooxidans 房间通过吸附，希腊语的第六个字母潜力和弥漫的反射英尺红外被调查大小。当絮凝行为被 Turbiscan 大小检验时，矿物质 floatability 上的细菌的种类的影响被 ... 详细信息

铁的离子的粘附黄铁矿和黄铜矿矿物质上的成年 Leptospirillum ferrooxidans 房间通过吸附，希腊语的第六个字母潜力和弥漫的反射英尺红外被调查大小。当絮凝行为被 Turbiscan 大小检验时，矿物质 floatability 上的细菌的种类的影响被 Hallimond 筹款测试决定。矿物质等电位的点(pH 6.5 ? 7.5 ) 在和细菌的房间的相互作用向房间转移了等电位的点以后(pH 3.3 ) ，在矿物质上显示房间吸附的化学性质出现。与细菌的房间对待的矿物质的英尺红外系列显示出所有房间的存在功能的组意味着房间吸附。黄铜矿上的细菌的房间吸附与黄铁矿相比是更高的，它同意了房间与黄铁矿比较的黄铜矿筹款和显著絮凝行为上的更大的萧条效果。

关键词：细菌硫矿絮凝浮选