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Photoproduction of multi-meson final states–recent results from the Crystal-Barrel/TAPS experiment at ELSA-

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chinese Physics C 2009年第12期33卷 1105-1112页

作者： u. Thoma HISKP Universitt Bonn Nussallee 14-16 53115 Bonn Germany

Multi-meson final states such as γp →pπ0π0 and γp →pπ0η have been investigated with the Crystal-Barrel/TAPS experiment at ELSA. Baryon cascades via △π and △η and also via higher mass baryon resonances are clearly observed. Based on this data and on data from other reactions a partial wave analysis has been performed from which partial decay widths of various N＊ and △＊ states into the different pπ0π0 and pπ0η decay channels have been determined, leading partly to unexpected results. In addition, polarisation observables have been investigated. The beam asymmetry X has been determined for both reactions and double polarisation data using a longitudinally polarised target and a circularly or linearly polarised photon beam has been taken. Given the angular coverage of the Crystal-Baxrel/TAPS experiment this data covers almost the full angular range and phase space. This data will provide new and important information for the partial wave analyses and bring us one step closer towards a complete experiment.

关键词： baryon spectroscopy photoproduction multi-meson final states polarisation observables

ADVANCED NICKEL-BASED AND NICKEL-IRON-BASED SuPERALLOYS FOR CIVIL ENGINEERING APPLICATIONS

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Acta Metallurgica Sinica(English Letters) 2005年第4期18卷 453-462页

作者： u. Brill ThyssenKrupp VDM GmbH 58791 Werdohl Germany

The use of high-temperature materials is especially important in power station construction, heating systems engineering, furnace industry, chemical and petrochemical industry, waste incineration plants, coal gasification plants and for flying gas turbines in civil and military aircrafts and helicopters. Particularly in recent years, the development of new processes and the drive to improve the economics of existing processes have increased the requirements significantly so that it is necessary to change from well-proven materials to new alloys. Hitherto, heat resistant ferritic steels sufficed in conventional power station constructions for temperatures up to 550℃ newly developed ferritic/martensitic steels provide sufficient strength up to about 600 - 620℃. In new processes, e.g. fluidized-bed combustion of coal, process temperatures up to 900℃ occur. However, this is not the upper limit, since in combustion engines, e.g. gas turbines. Material temperatures up to 1100℃ are reached locally. Similar development trends can also be identified in the petrochemical industry and in the heat treatment and furnace engineering. The advance to ever higher material temperatures now not only has the consequence of having to use materials with enhanced high-strength properties, considerable attention now also has to be given to their chemical stability in corrosive media. Therefore not only examples of the use of high-temperature alloys for practical applications will be given but also be contributed to some general rules for material selection with regard to their high-temperature strength and corrosion resistance.

关键词： nickel-based alloy high-temperature strength high-temperature corrosion resistance civil engineering application

面向小型服务器拒绝服务攻击的轻量级入侵检测系统

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面向小型服务器拒绝服务攻击的轻量级入侵检测系统

作者： MAI NG（？）C ch（A|^）u 华中科技大学

学位级别：硕士

随着硬件价格的下降和网络服务的发展，小型服务器和经验不足的用户在快速的增加。因此，越来越多的轻量级安全软件专注于这个方向。虽然拒绝服务攻击已经被明确的定义，分类和分析，但是如何防范他们还存在着许多的问题。绝大多数的拒... 详细信息

随着硬件价格的下降和网络服务的发展，小型服务器和经验不足的用户在快速的增加。因此，越来越多的轻量级安全软件专注于这个方向。虽然拒绝服务攻击已经被明确的定义，分类和分析，但是如何防范他们还存在着许多的问题。绝大多数的拒绝服务攻击都被因特网服务提供商防范了（阻止了），但是还是每天还是有很多拒绝服务攻击发生。虽然他们被视为小的攻击，轻易的穿透了因特网服务提供商的防范，但是他们可能会造成小型服务器的崩溃。因此，专注于建立一个小型轻量的程序通过分析流量包来识别DoS攻击。通过基于主机入侵检测机制技术和BLINC概念相结合，收集并建立了基于协议的几个Graphlet识别关系图，然后，设计并实现了一个基于网络的入侵检测微型系统。在网络上，该项目可以基于网络或者基于主机IDS模式工作。区别于采用使用规则和事先定义特征码方法的大多数IDS，流量包可以分析攻击模式。这个轻量级检测系统不需要获取包载荷，端口号和其他的附加信息。这将使得CPu和内存的使用率在相当程度上下降。除此之外，图形界面和对多平台的高适应性能够使得非熟练用户能够容易使用。

关键词：拒绝服务轻量级入侵检测系统 Graphlet BLINC概念

Biological and mechanical investigation of novel flax/silk protein-based nanofibrous scaffold for bone regeneration

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Progress in Natural Science:Materials International 2022年第4期32卷 443-455页

作者： M.Rama u.Vijayalakshmi Department of chemistry School of Advanced Sciences Vellore Institute of Technology

The process of bone tissue regeneration involves an intricate network of a biological macromolecules that includes proteins and peptides to support stimulation and healing response. Here, we have fabricated a novel flaxseed/silk fibroin based(dual protein) composite nanofibers using β-TCP to improve the biological properties and promote cartilage tissue regeneration along with a controllable rate of biodegradation. The physiochemical properties of PVA/β-TCP/FP:SF were characterized by FTIR, XRD, SEM, porosity, contact angle measurements and mechanical evaluation etc. This study demonstrates the biological performance of the developed nanofibers by using hemocompatibility, biodegradation ability, and apatite deposition in stimulated body fluid. Moreover, the cell viability assay was performed on MG-63 osteoblast cells and long-term antibacterial rate against E. coli and S. aureus was analysed. Docking results of flax protein and silk fibroin protein further confirmed the stable modes of intramolecular bonding and the most stable electrostatic values using theoretical calculations. Taken together,the experimental results proved that the dual protein-based fibrous scaffold was found to be up-regulated in terms of biological activity with enhanced cell adhesion and proliferation.

关键词： Flax protein Silk fibroin β-TCP Electrospinning Docking Bone regeneration

Optimized design of collector topology for offshore wind farm based on ant colony optimization with multiple travelling salesman problem

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Journal of Modern Power Systems and Clean Energy 2018年第6期6卷 1181-1192页

作者： Ramu SRIKAKuLAPu Vinatha u Department of Electrical and Electronics Engineering National Institute of Technology Karnataka

A layout of the offshore wind farm(OSWF)plays a vital role in its capital cost of installation. One of the major contributions in the installation cost is electrical collector system(ECS). ECS includes: submarine cables,number of wind turbines(WTs), offshore platforms etc. By considering the above mentioned problem having an optimized design of OSWF provides the better feasibility in terms of economic considerations. This paper explains the methodology for optimized designing of ECS. The proposed methodology is based on combined elitist ant colony optimization and multiple travelling salesman *** objective is to minimize the length of submarine cable connected between WTs and to minimize the wake loss in the wind farm in order to reduce the cost of cable and cable power loss. The methodology is applied on North Hoyle and Horns Rev OSWFs connected with 30 and 80 WTs respectively and the results are presented.

关键词： Ant colony optimization Offshore wind farm Multiple travelling salesman problem Wake effect Wake loss

Synthesis and Crystal Structure of Trans-bis(acesulfamato-O)tetraaquazinc(Ⅱ)

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chinese Journal of Structural chemistry 2010年第7期29卷 1047-1050页

作者： SAHIN Onur ICBuDAK Hasan B(u|¨)Y(u|¨)KG(u|¨)NG(O|¨)R Orhan Department of Physics Faculty of Arts and SciencesOndokuz Mayis UniversitySamsunTurkey Department of chemistry Faculty of Arts and SciencesOndokuz Mayis UniversitySamsunTurkey

The title compound, trans-bis（acesulfamato-O）tetraaquazinc（Ⅱ）（I, C8H16N2O12S2Zn）, crystallizes in the triclinic system, space group P1 with a = 5.1638（5）, b = 8.5338（9）, c = 9.9583（9）A, α = 74.325（8）, β = 81.112（7）, γ = 75.800（8）°, V= 407.77（7） A3, Z = 1, F（000） = 236, Rint = 0.085, T= 296 K, the final R = 0.029 and wR = 0.078 for 1832 observed reflections with I〉 2σ（0. The ZnⅡcentre resides on a centre of symmetry and has a distorted octahedral geometry. The basal plane is defined by two carbonyl O atoms of two monodentate trans-oriented acesulfamato ligands and two trans-aqua ligands. The axial positions in the octahedron are occupied by two trans-aqua ligands. Intermolecular O-H…O hydrogen bonds produce R22（8） and R22（16） rings, which lead to two- dimensional polymeric chains.

关键词： crystal structure zinc(Ⅱ) octahedral complex hydrogen bonds

Forced and Natural Vibrations of an Orthotropic Pre-Stressed Rectangular Plate with Neighboring Two Cylindrical Cavities

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Computers, Materials & Continua 2017年第1期53卷 1-22页

作者： u.Babuscu Yesil Department of Mathematical Engineering Faculty of Chemical and Metallurgical Eng.Yildiz Technical UniversityDavutpasa Campus34210EsenlerIstanbulTurkey.

Forced and natural vibrations of a rectangular pre-stressed orthotropic compositeplate containing two neighboring cylindrical cavities whose cross sections are rectangularwith rounded-off corners are investigated numerically. It is assumed that all the end surfacesof the rectangular pre-stressed composite plate are simply supported and subjected to auniformly distributed normal time-harmonic force on the upper face plane. The consideredproblem is formulated within the Three-Dimensional Linearized Theory of Elastic Waves inInitially Stressed Bodies (TDLTEWISB). The influence of mechanical and geometricalparameters as well as the initial stresses and the effect of cylindrical cavities on the dynamicalcharacteristics of the rectangular orthotropic composite plate are analyzed and discussed.

关键词： Initial stresses vibration cylindrical cavities 3D FEM orthotropic material.

3D RNA nanocage for encapsulation and shielding of hydrophobic biomolecules to improve the in vivo biodistribution

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Nano Research 2020年第12期13卷 3241-3247页

作者： Congcong Xu Kaiming Zhang Hongran Yin Zhefeng Li Alexey Krasnoslobodtsev Zhen Zheng Zhouxiang Ji Sijin Guo Shanshan Li wah.ch.u Peixuan Guo Center for RNA Nanobiotechnology and Nanomedicine College of PharmacyDivision of Pharmaceutics and Pharmaceutical ChemistryCollege of MedicineDorothy M.Davis Heart and Lung Research InstituteJames Comprehensive Cancer CenterThe Ohio State UniversityColumbusOH43210USA Department of Bioengineering James H.Clark CenterStanford UniversityStanfordCA94305USA Department of Physics University of Nebraska at OmahaOmahaNE68182USA Nanoimaging Core Facility Office of Vice-Chancellor for ResearchUniversity of Nebraska Medical CenterOmahaNE68198USA SLAC National Accelerator Laboratory Stanford UniversityMenlo ParkCA94025USA

Ribonucleic acid(RNA)nanotechnology platforms have the potential of harboring therapeutics for in vivo delivery in disease ***,the nonspecific interaction between the harbored hydrophobic drugs and cells or other components before reaching the diseased site has been an obstacle in drug *** we report an encapsulation strategy to prevent such nonspecific hydrophobic interactions in vitro and in vivo based on a self-assembled three-dimensional(3D)RNA *** placing an RNA three-way junction(3WJ)in the cavity of the nanocage,the conjugated hydrophobic molecules were specifically positioned within the nanocage,preventing their exposure to the biological *** assembly of the nanocages was characterized by native polyacrylamide gel electrophoresis(PAGE),atomic force microscopy(AFM),and cryogenic electron microscopy(cryo-EM)*** stealth effect of the nanocage for hydrophobic molecules in vitro was evaluated by gel electrophoresis,flow cytometry,and confocal *** in vivo sheathing effect of the nanocage for hydrophobic molecules was assessed by biodistribution profiling in *** RNA nanocages with hydrophobic biomolecules underwent faster clearance in liver and spleen in comparison to their ***,this encapsulation strategy holds promise for in vivo delivery of hydrophobic drugs for disease treatment.

关键词： ribonucleic acid(RNA)nanocage three-way junction(3WJ) encapsulation hydrophobic biomolecule RNA nanotechnology

A variable precision rough set approach to knowledge discovery in land cover classification

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International Journal of Digital Earth 2016年第12期9卷 1206-1223页

作者： Iftikhar u.Sikder Department of Information System Cleveland State UniversityOHUSA Department of Electrical Engineering and Computer Science Cleveland State UniversityOHUSA

This paper presents a granular computing approach to spatial classification and prediction of land cover classes using rough set variable precision *** particular,it presents an approach to characterizing large spatially clustered data sets to discover knowledge in multi-source supervised *** evidential structure of spatial classification is founded on the notions of equivalence relations of rough set *** allows expressing spatial concepts in terms of approximation space wherein a decision class can be approximated through the partition of boundary *** paper also identifies how approximate reasoning can be introduced by using variable precision rough sets in the context of land cover *** rough set theory is applied to demonstrate an empirical application and the predictive performance is compared with popular baseline machine learning algorithms.A comparison shows that the predictive performance of the rough set rule induction is slightly higher than the decision tree and significantly outperforms the baseline models such as neural network,naïve Bayesian and support vector machine methods.

关键词： Rough set theory soft computing granular computing remote sensing approximate reasoning