bluuebunny/crossref_metadata_2025 huggingface dataset:
Design of a Novel Automatic Access Control System
Authors: Zhang Ling Juan
Published: May 2014

To solve the shortcoming of access control system of venues, a novel automatic control system is designed. It is divided into electronic tickets, access door control nodes and management service center. The hardware is designed based on RFID technology and embedded ARM. The software is designed based on μC/OS-II, embedded C language and database programming technology. Experimental results and analysis show that the average management efficiency of the proposed system is 38.4% higher than that of traditional manual methods, and the average control accuracy is about 48.9% higher than that of the manual approach. The system can effectively enhance the level of automation and efficiency of the venues access control, and it has higher practical value and promotional value.
Research on Applied Technology in Assessing the Application Effectiveness of CIS Based on Digital Command of CIS
Authors: Chen Zhi You , Zou Zi Li , Peng Yong Jun
Published: May 2014

In order to research on applied technology in assessing the application effectiveness of command information system (CIS) based on digital command of CIS, the article sticks tightly the army operations during wartime, setting up the index system of the effectiveness assessment. The paper putts forward the whole assessment index architecture. By computing index gray white clustering coefficient and weight vector and setting up multilayers gray clustering effectiveness valuation mode, the thesis uses the judgment matrix of effectiveness valuation, assessing the effectiveness of the application of CIS under the " based on digital command mode" and " based on audio command mode". Based on the valuation conclusion, the article explains these important factors to the system effectiveness and provides a research basis for making some scientific improvement measures.
Applied-Information Technology and Data Processing for Multi-Objective Interval Job Shop Scheduling Problem with Flexible Preventive Maintenance
Authors: Xu Xiao Qiang , Lei De Ming
Published: May 2014

Interval job shop scheduling problem with flexible preventive maintenance is considered and an multi-objective swarm-based neighborhood search (MOSNS) is proposed for minimizing interval makespan and total interval tardiness. A dominance based greedy principle is utilized to decide if the old solution is replaced with the new one. A solution with the highest rank is replaced with a randomly chosen member of the non-dominated set every few number of iterations. Computational results show that MOSNS is an effective approach to solve the considered problem.
Intelligent Control System on Traffic Flow under the Keep-Right-Except-to-Pass Rule
Authors: Zha Yi Hui
Published: May 2014

This paper studied the traffic flow under the keep-right-except-to-pass rule on freeways and the effect of intelligent control system on traffic flow. Through the analysis of the basic traffic flow equation, we developed the traffic flow-traffic density model, obtained the maximum traffic flow, determined the model parameters and tested the model. We defined an indicator reflecting of the degree of traffic flow distribution according to the Gini coefficient in economics and built an effect evaluation model to study the effect of intelligent control system on traffic flow.
Applied Research with Two Modified Three-Step Algorithms Based on Double Newton Method for Solving Nonlinear Equations
Authors: Fang Liang
Published: May 2014

With the rapid development and wide application of information engineering and applied technology, nonlinear problems become an important direction of research in the field of numerical calculation and analysis. In this paper, we mainly study the iterative methods of nonlinear equations. We present and analyze two modified three-step Newton-type methods based on double Newton method for solving nonlinear equations. One is sixth-order convergent, while the other is seventh-order convergent. Both methods are free from second derivatives. The efficiency indices of the presented methods are 1.4310 and 1.4758, respectively, both of which are better than that of the classical Newton’s method 1.414. Some numerical experiments illustrate the efficiency and performance of the proposed methods.
Research on Swarm Intelligence Algorithm with an Artificial Bee Colony Algorithm for Lot Streaming Problem in Job Shop
Authors: Xu Xiao Qiang , Lei De Ming
Published: May 2014

The lot streaming (LS) problem in job shop with equal-size sub-lots and intermittent idling is considered. An effective swarm intelligence algorithm with an artificial bee colony (ABC) algorithm is proposed for the minimization of total penalties of tardiness and earliness. In the first period of ABC, the employed bee phase and the onlooker bee phase are both for lot/sub-lot scheduling. In the second period, the LS conditions are determined in the employed bee phase and the lot/sub-lot is scheduled in the onlooker phase. The worst solution of the swarm is replaced with the elite one every few cycles. Computational results show the promising advantage of ABC.
Applied-Information Technology with Method of Digital Image Noise Processing
Authors: Yu Guo Qing , Sui Chen Meng , Sui Bing Dong
Published: May 2014

Digital image processing is a kind of technology which employs a certain algorithm to realize image processing through computer algorithm. The powerful capacity of computing and graphics displaying function of Matlab makes image processing becomes more simple and intuitive. This paper introduces the basic knowledge of dealing with noise in digital image, expounds the neighborhood average method, median filtering in detail, and low pass filtering and other typical of eliminating noise method , and at the same time analyzes and compares the characteristics of several typical methods by use of the software Matlab.
Intelligent Research for Chinese Intelligent Urban Construction Problems and Solutions - Intelligent Traffic Forecast
Authors: Wu Yun Na , Xu Ru Hang
Published: May 2014

Smart city is a promising form for future city management. Intelligent transportation plays an important role in the smart city. Traffic forecast is an important way to realize intelligent traffic. This paper proposed a method to solve the complex mapping problem in traffic forecast based on BP artificial neural intelligence method. Data of the City of Alexandria in the U.S. is used to testify the feasibility of the method. The result shows that this method shows good performance in solving complex mapping problem.
The Design of New Type Food Mixer
Authors: Chen Shou An , Wang Jin Ge , Deng Xing Qiao
Published: May 2014

To solve the problem that in the pickled vegetable production, factory still use artificial labor ignore automated production. this situation lead to low productivity of Chinese pickled vegetable process. The other problem is that manual operations on the food quality, taste and health is difficult to control. In order to solve these two problems, I designed a new automated food mixer which apply automation technology, automatic weighing the main ingredient of feed and feed materials. only one person can completed the whole requires that from feeding to stirring. It can greatly reduces labor costs and labor intensity, the popularize of the food mixer will create a lot of economic value.
Mechanical Properties of Cu-Ni-Zn/Cu-Cr/Cu-Ni-Zn Composite Plate Processed by Explosive Bonding and Cold Rolling
Authors: Kang Gyeong Tae , Song Jae Sook , Hong Sun Ig
Published: May 2014

Mechanical properties of 3-ply Cu-Ni-Zn/Cu-Cr/Cu-Ni-Zn clad composite plates prepared by explosive bonding and cold-rolling. No intermetallic compounds were observed at the Cu-Ni-Zn/Cu-Cr interface after explosive bonding and cold-rolling and heat-treatment at 723K. The strength of as-rolled clad plate reached up to 575MPa with the ductility of 30% after heat treatment at 723K for 1 hour. The strength dropped to 510MPa and the ductility increased to 48% after heat treatment at 723K for 1.5 hour. There are no stepwise drops of the flow stress before final fracture, meaning three plates were bonded together until the last moment of the stress-strain curve. The observation of the fractured specimens revealed no interface separation even after fracture. The excellent mechanical reliability and the good interfacial bonding strength can be attributed to the absence of detrimental interfacial reaction compounds between Cu-Ni-Zn and Cu-Cr after annealing.
The Nature of Intermetallic Compounds and its Effect on Mechanical Properties of Cu/Al/Cu Clad Metals
Authors: Kim Won Nyeon , Hong Sun Ig
Published: May 2014

The mechanical properties and microstructure of layered Cu/Al/Cu composites was investigated after annealing at various temperatures. The nature of intermetallic compounds in roll-bonded Cu/Al/Cu clad metals after heat treatment was investigated using SEM, XRD and EBSD.in the temperature range 200~500oC. In the roll-bonded 3-ply Cu/Al/Cu clad metal, no visible interfacial reaction compound and defects were observed at the interfaces. The reaction layer was observed grow rapidly at the Cu/Al interface after annealing at and above 400oC, which deteriorated the ductility of clad metals. Intermetallic reaction layers of Cu/Al/Cu clad materials annealed at 500oC for 3, 5, 10hours was found to consist of three layers, CuAl2, CuAl and Cu9Al4. EBSD analyses revealed that intermetallic layers are polycrystalline. The drastic decrease of stress and elongation in Cu/Al/Cu clad composite annealed at 500oC can be linked to the interfacial cracks between Al and Cu layer.
Statics Analysis of Rails on CNC Glass Edger
Authors: Xiao Zhi Feng , Le Jian Bo , Wu Nan Xing
Published: May 2014

As rails of edger system and carved system in the CNC glass edger are often shocked by the millstone and tool, the rails would be suffered axial pressure stress and shear stress. At last, the quality of glass products is poor due to deformation of rails, even the CNC glass edger would be destroyed. The distribution of stresses and displacement of rails are contained by conducting a finite element static analysis on this important components. It shows that the maximum stress and maximum displacement of rails are within the allowable range by comparing the results, so the rails meet the requirements.
Photochromism and Fluorescent of a Novel Diarylethene Bearing Methylpyridine Group
Authors: Cui Shi Qiang , Sun Feng Xia , Pu Shou Zhi
Published: May 2014

A new unsymmetrical photochromic diarylethene compound, 1-(2-methyl-3-benzofuranyl)-2-[2-methyl-5-(2-methyl-6-pyridyl)-3-thienyl] perfluorocyclopentene (1o), was synthesized and its photochemical, fluorescence properties were investigated systematically both in solution and PMMA amorphous film. The photochromic reaction kinetics results indicated that the cyclization processes of1obelong to the zeroth order reaction and the cycloreversion process belong to the first order reaction.
Synthesis and Photochromism Studies of 1-(2,5-Dimethyl-3-Thienyl)-2-[2-Methyl-5-Naphthyl-3-Thienyl] Perfluorocyclopentene
Authors: Dong Xiao Rong , Xu Hong Yan , Pu Shou Zhi
Published: May 2014

A novel photochromic diarylethene 1a has been synthesized. Its photochemical properties, including photochromic behavior and kinetics, have been investigated in detail. The result indicated that the Diarylethene 1a changed the color from colorless to pink irradiation with 297 nm UV light, in which absorption maxima were observed at 548 nm in hexane. The photochromic reaction kinetics indicated that the cyclization processes of 1a belong to the zeroth order reaction and the cycloreversion process belong to the first order reaction. The back irradiation by appropriate wavelength visible light regenerated its open-ring isomers and recovered the original emission intensity.
Friction and Wear Properties of Al-Based Hypereutectic Silicon Coatings Fabricated by Supersonic Particles Deposition on ZM5 Magnesium Alloy
Authors: Shi Xiao Jun , Jiang Hai Bo , Yao Ju Kun , Wang Zhi Qian , Zhou Chao Ji , Meng Xiang Min
Published: May 2014

To improve the anti-wear properties of Mg alloys, Al-13Si, Al-15Si and Al-19Si coatings were prepared by supersonic particles deposition on the surface of ZM5 magnesium alloy. Micro-structure and anti-wear properties of the coatings were examined by digital micro-hardness tester, XRD, friction and abrasion testing machine, three-dimensional microscope and SEM. The results show that the wear-resistant layer and the magnesium substrate can be well integrated as mechanical bonding and the main wear failure mechanism of the three coatings is adhesive wear. Moreover, the micro-hardness of Al-19Si coating is 141.47HV0.05, much higher than Al-13Si coating (134.97HV0.05) and Al-15Si coating (136.02HV0.05). Besides, the anti-wear properties of Al-19Si coating is optimal, superior to Al-15Si coating and Al-13Si coating. All of those indicate that Al-19Si coating can provide the most excellent anti-wear protection for ZM5 magnesium alloy.
Hexavalent Chromium Leaching Influenced Factors in the Weathering Chrome Slag
Authors: Liu Shuai Xia , Chen Liang , Gao Yu Mei
Published: May 2014

The distribution of hexavalent chromium in the weathering slag was studied, as well as the influenced factors of aqueous agent leaching chromium. Results showed an optimal leaching condition: the chromium particle size is 100~200 mesh, the liquid-solid ratio is 25:1, the leaching time is 4~8h. Enhanced temperature and reduced pH value are benefit to hexavalent chromium leaching. Considering the equipment corrosion of low pH, the optimal pH value is 3~4.
Nonlinear Dynamics Analysis of Excitation Frequency under the Influence of the Rotor-Stator-Bearing System with Rub-Impact Fault
Authors: Liu Gui Zhen , Yu Ying , Wen Bang Chun
Published: May 2014

Established the unsteady oil-film force with rub-impact fault of rotor-stator-bearing system mechanical models by using Lagrange equation, Application of numerical analysis to study it, concluded that the rotor system in frequency as the only incentive system control parameters of orbit and bifurcation diagrams; analysis of the nonlinear behavior of the response of the system and the failure mechanism, provide a theoretical basis for the safe operation of the rotor system and fault diagnosis. The results show that, when the excitation frequency as the only control parameters, the system exist periodic motion, quasi periodic motion and chaotic motion etc abundant nonlinear phenomena.
Stability Prediction and Dynamics Analysis of Milling with Variable Pitch Cutter in Low Radial Immersion
Authors: Jin Gang , Qi Hou Jun , Lou Li Yan
Published: May 2014

By disrupting the regenerative effect, milling cutters with variable-pitch are usually used to improve stability. Since high interrupted cutting processes, such as low radial immersion case, will result in more nonlinear phenomena and some consequent differences of stability chart, in this paper, an improved semi-discretization algorithm is utilized to predict the stability lobes for variable-pitch milling under low radial immersion ratios, the focus of the current manuscript is to investigate the stability trend caused by tool geometries. In addition, the chart differences in the cases of low and high radial immersion milling are also discussed by comparisons. Under certain combinations of parameters, some phenomena, like bunch of isolated island and flip bifurcation region are described, and some influences of tool geometries on stability trends are shown and explained.
Aerodynamic Design and Modal Analysis on Wind Turbine Blade Based on CAD/CAE
Authors: Zhou Qian Qian , Sun He , Liu Chun Bao , Wang Yang , Liu Xiao Guang
Published: May 2014

Wind turbine blade is an important component to capture wind energy and converse energy. Basing on Wilson optimization method and engineering pratice, 2MW wind turbine blade’s aerodynamic profile is designed. Meanwhile, in order to avoid the resonance damage, top 10 rank modal frequencies and displacement gradient distribution contours are obtained through modal analysis. The results show that blade’s natural frequency does not coincide with the external excitation frequency, which avoids the resonance damage. Blade’s major vibration forms are waving and shimmy, requiring the ability of excellent resisting torsion. Therefore, the design should enhance bending stiffness of the blade. This paper provides an effective method for large wind turbine blades’ design and optimization.
Flow-Field and Hydromechanics Analysis of High Pressure Water-Jet Single Nozzle in Radial Horizontal Drilling
Authors: Yi Xian Zhong , Yi Song Lin , Shu Hui , Ji Yuan Qiang , Jiang Sheng Zong
Published: May 2014

The technology of high pressure water jet in radial drilling has currently been used widely at home and abroad. A numerical simulation and analysis of the internal and external flow fields of jet nozzle will 1ay the foundation for the further study of high pressure water jet rock breaking. The physical and mathematical models of axial-symmetrical submerged jet rock breaking with single nozzle were established. And a numerical simulation of the internal and external flow fields of high pressure water jet nozzle in radial drilling was conducted with the Fluent software. The 1aws of the internal and external flow fields were analyzed in different jet distances and inlet flow rates.
Research on Mechanical Mechanics with Trajectory Reconstruction Model of Motorcycle’s Three-Dimensional Rolling Movement
Authors: Cao Yi , Zuo Zhong Yi , Liu Bo Hang
Published: May 2014

In order to simulate and analyze the rolling movement state of motorcycle in collision accidents, the trajectory reconstruction model was studied. The motorcycle’s centroid trajectory model during the process of rolling and the feature point trajectory model during the process of sliding are both constructed. Using the accidents reconstruction and analysis software named PC-Crash and the models constructed in this paper respectively, a real accident case was reconstructed and analyzed. The comparative study between the reconstruction analysis results and the marks remained in the accident scene was conducted. Research showed that, the analysis result reconstructed by the model was consistent with the actual accident scene. This model can be used to reconstruct and analyze the motorcycle’s rolling movement trajectory after collision occurring.
Thermomechanical Fractional Derivative Model of Viscoelastic Isolators
Authors: Zhang Zhen Li , Shang Chao , Shi Wei Hua
Published: May 2014

In vibration process, viscoelastic isolators’ temperature will rise due to energy dissipation, especially when the isolators have high damping characteristics. First, for the arbitrary loadings, the thermomechanical coupling model and the corresponding difference form are established based on the five-parameter fractional derivative model. Then, for the steady-state harmonic inputs, which is very common in engineering application, the derived model is significantly simplified by Fourier transformation. Finally, the proposed model is verified by experiments and shows a reasonable agreement with measured data.
Model Base Construction and Transfer Analysis for the Cylindrical Gear of SEW-F Reducer
Authors: Ma Wen Xuan , Wang Shi Jie , Chen Hong Wen
Published: May 2014

To improve reducer products quality, continuously innovate and make them more personalized and customized, based on CATIA, researches are on extracting models feature parameter, setting up model base interface parameter, obtaining parametric design source code and writing program code for the cylindrical gear of SEW-F speed reducer. Process outside accessible way has been used for the second development of CATIA. User interface and model base connection can be made. And gear model base has been built. Through inputting gear design parameter in the model base user interface, the part model can be transferred automatically so as to develop the products soon.
Biomechanical Characteristics Analysis on Taichi Yunshou Technique
Authors: Guan Tie Yu
Published: May 2014

Using 3D human motion analysis system and biomechanics knowledge, to explore the Taichi Yunshou technique. Twenty one healthy male adults were voluntarily involved in this study, they were divided into two group by training experience: professional group and amateur group. This study reached the conclusions that (a) there are significant difference between professional and amateur Taichi lovers in different phases in flex and extension angle changes of knee joint, (b) there are no statistical difference between professional and amateur Taichi lovers in different phases in varus and vulgus changes of knee joint in right heel strike,left forefoot off, and left heel strike, (c) during right forefoot off phase, there are significant difference between professional and amateur Taichi lovers.
Modeling and Simulation of Ship Intermediate-Level Support System Based on HLA
Authors: Li Fang , Hu Bin , Liu Gang
Published: May 2014

Ship intermediate-level support system is complex system. The modeling and simulation of the system are difficult. To solve this problem, we apply both UML and HLA for modeling and simulation of ship intermediate-level support system. First, UML is used to model the use case model and interaction model. On the basis of the models above, HLA is used to model object models. Finally, according to the simulation models above, simulation software is developed and simulation case is analyzed, which shows the simulation models can be used to evaluate and optimize ship intermediate-level support system by simulation.
Information-Applied Technology in Neural Network Prediction Model of Aviation Unsafe Event Based on PSO Algorithm with Gradient Acceleration
Authors: Gan Xu Sheng , Yang Can , Duanmu Jing Shun
Published: May 2014

To improve the level of aviation safety management and decision-making, an aviation unsafe event model based on neural network trained by an improved Particle Swarm Optimization (PSO) algorithm is proposed. First a gradient acceleration idea is introduced in standard PSO algorithm to improve the search efficiency, and then the improved PSO algorithm is used to optimize the parameters of neural network, finishing the training of model. An actual example on unsafe event data of an airline shows that the proposed method can achieve a good prediction effect.
Information-Applied Technology with Nonlinear System Modeling Method of Elman Network Based on Particle Swarm Optimization
Authors: Wei Yan Ming , Li Hua Ping , Gao Hai Long
Published: May 2014

In order to improve the modeling ability for nonlinear system, an Elman modeling method based on Particle Swarm Optimization (PSO) algorithm is proposed. It uses PSO algorithm to optimize the parameters of Elman network. The simulation result shows that the proposed hybrid method combined Elman with PSO algorithm has a good modeling performance with fast training rate for complex nonlinear system.
Application of AJAX Technology and SSH Framework in Development of Electronic Commerce System
Authors: Xu Hong Sheng , Li Yong Liang , Li Chao
Published: May 2014

The characteristics of AJAX technology can read and write data without refreshing the page, so as to relieve the burden of server and speed up the response and shorten the waiting time for customers. The SSH framework is the organic integration of Struts, Spring and Hibernate three technologies. The e-commerce system has good hierarchical coding design thought of MVC system on the Struts2 framework. The paper presents application of AJAX and SSH framework in development of electronic commerce system.
Optimization Methodology for Composite Stiffened Panel Based on Genetic Algorithm
Authors: Jin Da Feng , Liu Zhe , Fan Zhi Rui
Published: May 2014

A novel optimization methodology for stiffened panel is proposed in this paper. The purpose of the optimization methodology is to improve the first buckling load of the panel which is obtained by finite element method. The stacking sequence of the stiffeners is taken as design variables. In order to ensure the manufacturability of design, the design guidelines of stacking sequence are taken into account. A DOE based on Halton Sequence makes the initial points of genetic algorithm spread more evenly in the design space of laminate parameters and consequently accelerates the search to convergence. The numerical example verifies the efficiency of this method.
Application of Ontology Technology in Building Knowledge Base of E-Commerce System in Direct Selling Clothing Network
Authors: Wang Yi , Zhang Jian Ming , Hu Jian Rong
Published: May 2014

Ontology technology is the foundation of the semantic Web, and provides support for the definition of domain ontology to the clothing e-commerce direct knowledge base, so as to realize the electronic commerce platform based on domain knowledge. In this paper, the design of the clothing network marketing e-commerce platform is an integrated product sales, product management, marketing and sales information entrance, marketing, customer relationship management and other functional modules operating platform. The paper presents application of ontology technology in building knowledge base of e-commerce system in direct selling clothing network. Experimental results show that the proposed application technology has high efficiency.
Full-Text Search Engine Technology Research Based on Lucene
Authors: Xu Chun Feng , Xu Hong Hua
Published: May 2014

As an important branch of modern information retrieval technology, full-text search is not only an important tool for dealing with unstructured data, but also one of the mainstream technology of search engines .This paper starts from studying the working principles and process of search engine model in deep and discuss Lucene's architecture with previously knowledge. The main emphasis is placed on the problem of some basic algorithms of Chinese word segmentation and Relevance Ranking. Finally, we set up a system based on Lucene of full-text retrieval by applying these technologies.
Synthesis and Properties of [1-(1,2-dimethyl-cyano-3-pyrrole)-2-(2-methyl-5-thienyl-3-thienyl]perfluorocyclopentene
Authors: Fu Ying Long , Li Xue , Liu Gang
Published: May 2014

A new unsymmetrical photochromic diarylethene [1-(1,2-dimethyl-cyano-3-pyrrole)-2-(2-methyl-5-thienyl-3-thienyl] perfluorocyclopentene (1o) has been synthesized, and its photochromic reactivity, fluorescent were also investigated. The results showed this compound exhibited reversible photochromism, undergoing reversible cyclization and cycloreversion reactions upon alternating irradiation with UV and visible light in solution,Diarylethene 1 changed the color from colorless to purple upon irradiation with 297 nm UV light, in which absorption maxima were observed at 585 nm in hexane.
Synthesizes and Properties Research of a Photochromic Diarylethene Bearing a Ethynyl Moiety
Authors: Sun Feng Xia , Cui Shi Qiang , Pu Shou Zhi
Published: May 2014

A new unsymmetrical photochromic diarylethene compound, 1-(2-Methyl-3-benzothiophene)-2-(5-(4-ethynyl)-2-methylthiophen-3-yl)Perfluorocyclopentene (1o),was synthesized and its photochemical, fluorescence properties were investigated systematically both in solution and PMMA amorphous film. The results showed that this compound exhibited reversible photochromism, changing from colorless to pink after irradiation with 297 nm UV light both in solution and in PMMA amorphous film. The photochromic reaction kinetics indicated that the cyclization processes of 1 belong to the zeroth order reaction and the cycloreversion process belong to the first order reaction.
Synthesis, and Properties of 1-[2-methyl-5-(1,3-difluorophenyl)-3-thienyl]-2-[2-methyl-5-(4-methoxylphenyl)-3-thienyl]perfluorocyclopentene
Authors: Tian Zhao Yan , Sun Feng Xia , Pu Shou Zhi
Published: May 2014

A new unsymmetrical photochromic diarylethene 1-[2-methyl-5-(1,3-difluorophenyl)-3-thienyl]-2-[2-methyl-5-(4-methoxylphenyl)-3-thienyl] perfluorocyclopentene has been synthesized,which a methoxyl group was substituted at the para-positions of the terminal phenyl ring. The photochromism of this compound was investigated, the results showed that this compound exhibited reversible photochromism, inducing cyclization and cycloreversion reactions upon alternating irradiation with UV and visible light both in solution and in a PMMA film. When irradiated 297 nm UV light, in hexane solution the maximum absorption was observed at 289 nm and 588 nm in opening-ring form and in close-ring form, respectively.
Rheological, Structural and Mechanical Characterization of Monolithic Zircon-Alumina Bodies
Authors: León-Carriedo M. , Chavarría C.A. Gutiérrez , Galicia J.L. Rodríguez , López-Cuevas Jorge , Canul M.I. Pech
Published: May 2014

In the present work, the characterization of monolithic materials formulated at different weight concentrations was conducted; employing two of the ceramic materials most used in the refractory industry, zircon and alumina. These monolithic materials were fabricated using colloidal techniques, specifically plaster casting mold, in order to obtain pieces with a higher particle consolidation and density, reducing porosity to lower values than the obtained using traditional shaping process of these materials. The monoliths were obtained employing two ceramic powders with different average particle size and morphology to achieve better packing in the green body. This characterization was carried out, firstly, determining the particle size of the raw materials by laser diffraction and the evaluation of particle morphology by scanning electron microscopy. Aqueous suspensions were formulated by containing both ceramic materials, which were dispersed with Tamol 963, and analyzed by rheometric techniques. Subsequently, bars were manufactured having the following dimensions; 4 mm wide, 3 mm thick and 45 mm in length, according to ASTM C1161-02cc, to be characterized microstructural and mechanically, also was observed the fracture habit after the mechanical test. As a final result, the materials formulated at higher alumina content showed higher density values, reaching 94.95% of the theoretical density, also showed a higher thermal expansion coefficient and high rupture modulus, reaching up to 600 MPa and Young modulus of 230 GPa. From the microstructure characterization it was observed that alumina matrix shows a transgranular fracture across the grains and zircon particles exhibited intergranular fracture among the grain boundaries.
The Role of Residual Stresses in Circumferential Welding Repairs of Pipelines in SCC Susceptibility
Authors: Contreras-Cuevas Antonio , Alamilla-López J. , Galván-Martínez Ricardo , Vega-Becerra O.
Published: May 2014

The main objective of the present study is to measure the residual stresses in the circumferential welding joints of X52 pipeline steel with multiple welding repairs, and then relate these residual stresses to study the influence on the high pH stress corrosion cracking (SCC) susceptibility. Four conditions of shielded metal arc welding (SMAW) repairs of the girth weld were evaluated. The residual stresses were measured through X-ray diffraction (XRD) on the internal side of the pipe in longitudinal and circumferential direction. Residual stresses in the circumferential and longitudinal direction reach values of about 98 and 74% of the yielding strength (360 MPa) respectively. The effect of residuals stresses in the high pH-SCC susceptibility of X52 pipeline steel was evaluated through slow strain rate tests (SSRT) in a simulated soil solution. Relation between SCC index and residual stresses on the SCC susceptibility was analyzed. Results of SCC index taking account the ratios obtained from the mechanical properties of the welding joints evaluate (containing different levels of residual stresses) showed good SCC resistance. It was observed that increasing the magnitude of residual stresses, the SCC susceptibility increases. For all the SSRT specimens the failure occurs in the base metal and heat affected zone (HAZ) interface.
Mechanical Response and Microstructure of Al-SiO2 Composites Prepared by Means of a Solid-State Route
Authors: Estrada-Guel Ivanovich , Carreño-Gallardo Caleb , Martínez-Sánchez Roberto
Published: May 2014

This study deals with the production of some Al-SiO2 composites and the evaluation of milling intensity over the distribution of silica particles into the Al matrix. Samples for mechanical characterization were prepared from powders by compaction and sintering using a solid-state route complemented with mechanical milling. The mechanical response was modified as a direct function of the milling intensity, but an adverse effect was observed with prolonged milling times. Electron microscopy studies reveal a homogeneous dispersion of insoluble particles into the Al matrix, which is associated with the high grain refinement in the synthetized composites giving an important improvement on the composites strength. Also, the silica spheroidal structure is not altered nor destroyed (mechanically and/or chemically) during the composite synthesis.
On the Mechanical Milling of the AlCuFe Icosahedral Phase with Water
Authors: Patiño-Carachure C. , López-Miranda J. Luis , de la Rosa F. , Abatal M. , Pérez R. , Rosas Trejo Gerardo Antonio
Published: May 2014

In this investigation the Al64Cu24Fe12 alloy was melted in an induction furnace and solidified under normal casting conditions. The as-cast sample was subject to a heat treatment at 700 oC under argon atmosphere in order to obtain the icosahedral quasicrystalline phase in a monophase region. Subsequently, the icosahedral phase was milled for different times and water added conditions. The pre-alloyed and milled powders were characterized using scanning electron microscopy, X-Ray diffraction, and transmission electron microscopy. The experimental results showed that the icosahedral phase is sensitive to the reaction between water and aluminum of the quasicrystalline alloy to generate hydrogen. As the milling time and the amount of water are increased, the embrittlement reaction of the alloy is accentuated releasing more hydrogen.
Densification Study of Cu-Al-SiC Composite Powders Prepared by Mechanical Milling
Authors: León-Patiño C.A. , Ramírez-Vinasco D. , Aguilar-Reyes E.A.
Published: May 2014

This work involves the preparation of Cu-Al-SiC composite powders by a high-energy milling process and the study of their densification behavior by cold compaction. The goal of the milling process is to get embedded the ceramic particles in the metal matrix to enhance the distribution of the metal and ceramic phases in the compacts, an important condition to derive in isotropic properties of consolidated materials. For comparison purposes, compressibility tests of a Cu-5Al matrix prepared by high-energy milling were performed; while additions of 1, 5 and 10 vol.% SiC were added to the matrix. It was found that the high-energy milling process leads to Cu-Al-SiC composite powders with a homogeneous distribution of the reinforcement in the matrix. Compressibility essays showed that densification of the powders decreased with SiC content; a densification of 73.7% was obtained for composites with 10% SiC compared to 76.0% for samples with 1% SiC at the maximum load applied. Milling time reduced the plastic deformation capacity of the matrix leading to fracture of the cold welded aggregates; the fracture process was accelerated by the addition of the hard reinforcement particles. Thus, morphology of the powders changed from laminar, to fine fragments and coarse aggregates, affecting the compaction behavior.
Influence of the Chemical Composition on the Ausferritic Transformation in Carbide-Free Bainitic Cast Steel
Authors: Basso Alejandro D. , Tenaglia Nicolás E. , Boeri Roberto Enrique , Massone Juan M.
Published: May 2014

This work focuses on the study of the solid state transformations that take place during the austempering of high silicon carbide-free bainitic cast steels with different chemical composition. In order to get this objective three cast steel melts with different chemical compositions were produced, evaluating the influence of Cr, Mn, Ni, Al and Co. For each of these steels, samples were subjected to an austempering heat treatment at 340 oC varying the austempering time from 5 sec to 120 sec. The results show that small regions of free ferrite were obtained during continuous cooling from the austenitising to the austempering temperatures in unalloyed high silicon cast steels. At short austempering time (5 sec), the presence of a small fraction of ausferrite was observed. Austempering for 60 sec showed a larger amount of ausferrite. However, the ausferritic reaction is incomplete, and some martensite also was present, mainly located in last to freeze (LTF) zones. After an austempering of 120 sec, a fully ausferritic matrix was obtained. The addition of Cr and Mo avoided the initial precipitation of free ferrite, and lowered the isothermal transformation kinetics. On the other hand the use of Al and Co increase the presence of ferrite formed during continuous cooling and accelerates the kinetics of the ausferritic reaction.
Is rewritten Bible/Scripture the solution to the Synoptic Problem?
Authors: Malan Gert J.
Published: May 2014

New Testament scholars have for centuries posited different solutions to the Synoptic Problem. Recently a new solution was proposed. Mogens Müller applies Geza Vermes’s term rewritten Bible to the canonical gospels. Accepting Markan priority, he views Matthew as rewritten Mark, Luke as rewritten Matthew, and John as additional source. This article examines Müller’s hypothesis by first investigating the history of the controversial term rewritten Bible/Scripture and its recent application to the New Testament Gospels. Müller’s hypothesis is then compared to other solutions to the Synoptic Problem, such as the Augustine, Griesbach, and Farrer-Goulder Hypotheses. The Two Document Hypothesis is discussed and Müller’s 2nd century Luke theory is compared to Burton Mack’s almost similar stance and tested with the argument of synoptic intertextuality in view of the possible but improbable early second century date for Matthew. Lastly, the relationship between the synoptic Gospels is viewed in terms of literary intertextuality. Müller suggests proclamation as motivation for the Gospels’ deliberate intertextual character. This notion is combined with the concept of intertextuality to suggest a more suitable explanation for the relationship between die Gospels, namely intertextual kerugma. This broad concept includes any form of intertextuality in terms of text and context regarding the author and readers. It suitably replaces rewritten Bible, both in reference to genre and textual (exegetical) strategy.
Effect of combined dexamethasone therapy with nebulized r-epinephrine or salbutamol in infants with bronchiolitis: A randomized, double-blind, controlled trial
Authors: Bawazeer Manal , Aljeraisy Majed , Albanyan Esam , Abdullah Alanazi , Thaqafi Wesam Al , Alenazi Jaber , otaibi Zaam Al , Ghaihab Mohammed Al
Published: May 2014

Background: This study investigated the effect of combining oral dexamethasone with either nebulized racemic epinephrine or salbutamol compared to bronchodilators alone for the treatment of infants with bronchiolitis. Materials and Methods: This was a double-blind, randomized controlled trial on infants (1 to 12 months) who were diagnosed in the emergency department with moderate-to-severe bronchiolitis. The primary outcome was the rate of hospital admission within 7 days of the first dose of treatment, and the secondary outcomes were changes in respiratory distress assessment instrument score, heart rate, respiratory rate, and oxygen saturation (O 2 Sat) over a 4-hour observation period. Infants (n = 162) were randomly assigned to four groups: A (dexamethasone + racemic epinephrine) = 45, B (placebo and racemic epinephrine) =39, C (dexamethasone and salbutamol) = 40, or D (placebo and salbutamol) = 38. Results: Patients who had received dexamethasone + epinephrine exhibited similar admission rates compared to placebo + epinephrine or salbutamol (P = 0.64). Similarly, no statistically significant difference was observed in the rate of hospitalization for patients who received dexamethasone + salbutamol compared to those who received placebo + epinephrine or salbutamol (P = 0.51). Clinical parameters were improved at the end of the 4-hour observation period for all treatment groups. Treatment with dexamethasone + epinephrine resulted in a statistically significant change in HR over time (P < 0.005) compared to the other groups. Conclusions: This study adds to a body of evidence suggesting that corticosteroids have no role in the management of bronchiolitis for young infants who are first time wheezers with no risk of atopy.
An assessment of diabetes care in Palestinian refugee camps in Syria
Authors: Alabed Samer , Guul Aisha , Crighton Claire , Alahdab Fares , Fares Munes , Morad Mohammad , Sonbol Mohamad B , Madmani Mohammed E , Sasa Anas , Unwin Nigel
Published: May 2014

Background: Palestinian refugees have been a displaced group of people since 1948, many of whom are living in refugee camps in the Middle East. They are entitled to free health care from the United Nations Relief and Work Agency (UNRWA). They show a higher prevalence of diabetes than the population in their host countries in the Middle East. This study examined the realities of care for diabetic patients in UNRWA health clinics in Damascus, Syria. The aim was three‑fold: To investigate the level of diabetes care, to probe patients′ level of general understanding of their disease and its management, and to search for areas of potential improvement. Methods: Data on patient education and care was gathered over a 1 month period from August 4, 2008 to September 4, 2008 using questionnaires and direct observation of the workflow at the clinics. Clinic‑led care was observed by the study team using checklists during patient visits. All of the clinic staff and sampled patients were interviewed. The main areas of care assessed were: Patient follow‑up; examination of eyes and feet; availability of medications; and patient education. A total of 154 people with diabetes were sampled from three refugee camps situated around Damascus. Results: A total of 154 patients, three doctors and seven nurses composed the sample of the study. Foot examinations were almost always neglected by health staff and eye examinations were not offered by the UNRWA clinics. Interviews with patients showed that: 67% (95% confidence intervals [CI]: 0.59‑0.70) had to buy their medication at their own expense at least once due to medication shortage in the UNRWA clinics, 48% (95% CI: 0.40‑0.55) displayed poor knowledge regarding the cause and exacerbating factors of diabetes, 65% (95% CI: 0.56‑0.72) had not heard of insulin, and 43% (95% CI: 0.35‑0.51) did not know for how long they needed to take their medications.
Shared Sanitation and the Prevalence of Diarrhea in Young Children: Evidence from 51 Countries, 2001–2011
Authors: Fuller James A. , Clasen Thomas , Heijnen Marieke , Eisenberg Joseph N. S.
Published: May 2014

Shared sanitation is defined as unimproved because of concerns that it creates unsanitary conditions; this policy is being reconsidered. We assessed whether sharing a toilet facility was associated with an increased prevalence of diarrhea among children < 5 years of age. We use data from Demographic and Health Surveys conducted in 51 countries. Crude and adjusted prevalence ratios (PRs) for diarrhea, comparing children from households that used a shared facility with children from households that used a non-shared facility, were estimated for each country and pooled across countries. Unadjusted PRs varied across countries, ranging from 2.15 to 0.65. The pooled PR was 1.09; differences in socioeconomic status explained approximately half of this increased prevalence (adjusted PR = 1.05). Shared sanitation appears to be a risk factor for diarrhea although differences in socioeconomic status are important. The heterogeneity across countries, however, suggests that the social and economic context is an important factor.
A Cluster Randomized Controlled Trial to Reduce Childhood Diarrhea Using Hollow Fiber Water Filter and/or Hygiene–Sanitation Educational Interventions
Authors: Lindquist Erik D. , George C. M. , Perin Jamie , Neiswender de Calani Karen J. , Norman W. Ray , Davis Thomas P. , Perry Henry
Published: May 2014

Safe domestic potable water supplies are urgently needed to reduce childhood diarrheal disease. In periurban neighborhoods in Cochabamba, Bolivia, we conducted a cluster randomized controlled trial to evaluate the efficacy of a household-level hollow fiber filter and/or behavior change communication (BCC) on water, sanitation, and hygiene (WASH) to reduce the diarrheal disease in children less than 5 years of age. In total, 952 households were followed for a period of 12 weeks post-distribution of the study interventions. Households using Sawyer PointONE filters had significantly less diarrheal disease compared with the control arm during the intervention period, which was shown by diarrheal prevalence ratios of 0.21 (95% confidence interval [95% CI] = 0.15–0.30) for the filter arm and 0.27 (95% CI = 0.22–0.34) for the filter and WASH BCC arm. A non-significant reduction in diarrhea prevalence was reported in the WASH BCC study arm households (0.71, 95% CI = 0.59–0.86).
Clinical Presentation of Dengue by Serotype and Year of Epidemic in Martinique
Authors: Thomas Laurent , Najioullah Fatiha , Besnier François , Valentino Ruddy , Césaire Jacques Rosine Raymond , Cabié André , _ _
Published: May 2014

During the last decade Martinique experienced four dengue epidemics, each characterized by the predominance of 1 or 2 serotypes. In this retrospective database analysis, we investigated the relationship between dengue serotype and disease severity. Data on dengue were collected from 715 patients (male/female ratio 0.87), 14 to 91 years of age (median 35 years) examined in the adult emergency department between 2005 and 2010. In this series, DENV-4 infections more frequently had a milder clinical presentation. The DENV-2 infections were most often secondary infections admitted at the critical phase of dengue illness with signs of plasma leakage. The DENV-1 infections were disabling, particularly in females, and most often led to disease of intermediate severity, without overt plasma leakage. These data were consistent with there being differences in virulence between serotypes, regardless of the host's immune status. However, secondary DENV-2 infections showed an increased risk of plasma leakage.
Neuroauditory Toxicity of Artemisinin Combination Therapies—Have Safety Concerns Been Addressed?
Authors: Ramos-Martín Virginia , González-Martínez Carmen , Mackenzie Ian , Schmutzhard Joachim , Pace Cheryl , Lalloo David G. , Terlouw Dianne J.
Published: May 2014

Although artemisinin-based combination therapies (ACTs) are widely viewed as safe drugs with a wide therapeutic dose range, concerns about neuroauditory safety of artemisinins arose during their development. A decade ago, reviews of human data suggested a potential neuro-ototoxic effect, but the validity of these findings was questioned. With 5–10 years of programmatic use, emerging artemisinin-tolerant falciparum malaria in southeast Asia, and the first calls to consider an increased dose of artemisinins, we review neuroauditory safety data on ACTs to treat uncomplicated falciparum malaria. Fifteen studies reported a neurological or auditory assessment. The large heterogeneity of neuro-ototoxic end points and assessment methodologies and the descriptive nature of assessments hampered a formal meta-analysis and definitive conclusions, but they highlight the persistent lack of data from young children. This subgroup is potentially most vulnerable to any neuroauditory toxicity because of their development stage, increased malaria susceptibility, and repeated ACT exposure in settings lacking robust safety monitoring.