bluuebunny/crossref_metadata_2025 huggingface dataset:
The Thermal Image Analysis and Fuel Conversion Characteristics on Porous Media-Catalyst Hybrid Reactor in Dry Auto-Thermal Reforming
Authors: Lai Ming Pin , Horng Rong Fang , Lai Wei Hsiang , Chou Huann Ming , Liao Cheng Hsun
Published: July 2015

The subject was to design a fuel converter of CO2, focusing on parameters on thermal image observation of porous media-catalyst interface during excess enthalpy reforming process. The methodology was using auto-thermal reforming technique to provide the heat of oxidation reaction. The heat provided the needed high temperature during CO2 reduction processing. H2-rich syngas was produced by the assistance of surface reaction of catalyst. The experiments were performed by using visualization technique for thermal image observation during reforming process. The results could be applied to the understand the temperature distribution. This study covers two parts, including thermal image observation, and reactant conversion characteristics under various reforming parameters. The experimental results show that the hybrid reformer can achieve excess enthalpy condition under the tested parameters. Additionally, the optimal CH4 conversion efficiency can reach 93.28 %. CO2 conversion efficiency is reaching between 0.35 and 8.65 %. The thermal image observation technique to determine catalyst local high temperature of reforming process is important in academic and practical application. Moreover, it provided information for basic research during reforming process
The Estimation of the Mechanical Property of the Porous Material by Numerical Analysis
Authors: Gonda Takeshi , Ohtsuka Shigeru , Yakabe Masaki , Hayamizu Yasutaka
Published: July 2015

Porous materials, such as filters made of sintered metals, lagging materials, and fireproof materials, are utilized in various fields. The porosity changes the characteristics of the materials. For example, with heat-insulating foam, the higher the porosity, the greater is the insulation factor. However, increased porosity leads to a decline in mechanical properties. Thus, when using porous materials, analyzing the mechanical strength is necessary. We modeled a porous structure of sintered metal sample and estimated the Young's modulus using the numerical analysis software “ADVENTURE” and compared the estimated value with the experimental value. Also, we modeled the effect of porosity and pore diameter on the mechanical property of the material. From the results, the Young's modulus decreases with increases in porosity and pore diameter, as expected.
Effect of Dry Ice Blasting on Removal of Loading Carbon Chips on Wheel Surface
Authors: Ohashi Kazuhito , Murakawa Soziro , Tsukamoto Shinya
Published: July 2015

In dry grinding of hard carbon parts, the grinding performance of wheel is remarkably lost by carbon chips loading on wheel surface. The deterioration in grinding performance of wheel affects the grinding accuracy and efficiency. Generally, the grinding performance of loading wheel recovers by dressing. However, the dressing is not suitable from a viewpoint of the wheel life and the production cost because many abrasive grains having sharp edges under loading carbon chips on wheel surfaces are lost by dressing. In this study, we propose the application of dry ice blasting as a removal method of loading carbon chips. The dry ice is little influence on the working environment because of the quick sublimation of dry ice particles to carbon dioxide. In addition, the dry ice blasting might be suitable for the chip removal method because the dry ice doesn’t remain on wheel surfaces after blasting without the damage of wheel surfaces. The dry ice blasting tests of resinoid bond diamond wheel surface with no grinding performance by loading carbon chips are carried out, and the effects of dry ice blasting on removal of loading carbon chips are investigated, analyzing the protrusion height of abrasive grains, the impact pressure in the dry ice blasting and so on.
Characterization of Novel Sorbents for Mercury Removal at Elevated Temperature
Authors: Cheng Han Wen , Yu Ching Tsung
Published: July 2015

The novel carbonate sorbents of Mg–Al–CO3 and (Mg3−x, Cux)–Al–CO3, were synthesized by co-precipitation method with individual nitrate salt of metal ions under alkaline conditions. The synthetic sorbent was characterized by analysis techniques such as BET surface area analysis, X-ray diffraction (XRD), and scanning electron microscopy (SEM). Elemental mercury capture experiments were carried out in a fixed-bed reactor including Hg permeation source, furnace, and Hg analyzer, which was conducted at temperature ranging from 30 to 300 o C. The major results showed that the surface area of material was significantly increased via incorporating Cu2+ into Mg–Al–CO3, accordingly enhancing Hg retention capacity of sorbents. SEM imagines displayed the layer appearance of Mg/Al and Mg/Cu/Al sorbents. Crystalline analysis indicated lamella structure accompanied with metal oxides within materials. Mercury removal tests demonstrated that the breakthrough time increased with temperature by adding transition metals to Mg–Al–CO3 as (Mg3−x, Cux)–Al–CO3. Hg uptake by the (Mg3−x, Cux)–Al–CO3 sorbent rapidly increased with elevated temperature up to 200 o C and reached the maximum capacity of 12.93 μg/g, and then gradually decreased after 300 o C. Surface area and unique properties of transition metals are the reason toward improving Hg capture sorbent. These results represent the feasibility of using such Hg sorbents for elemental mercury removal under elevated temperature conditions, and the detail mechanism is needed to be further studied.
Effects of Cooling Conditions on Thermal Crack Initiation of Brittle Cutting Tools during Intermittent Cutting
Authors: Yamaguchi Kenji , Fujita Tsuyoshi , Kondo Yasuo , Sakamoto Satoshi , Yamaguchi Mitsugu , Uehara Kazutake
Published: July 2015

It is well known that a series of cracks running perpendicular to the cutting edge are sometimes formed on the rake face of brittle cutting tools during intermittent cutting. The cutting tool is exposed to elevated temperatures during the periods of cutting and is cooled quickly during noncutting times. It has been suggested that repeated thermal shocks to the tool during intermittent cutting generate thermal fatigue and result in the observed thermal cracks. Recently, a high speed machining technique has attracted attention. The tool temperature during the period of cutting corresponds to the cutting speed. In addition, the cooling and lubricating conditions affect the tool temperature during noncutting times. The thermal shock applied to the tool increases with increasing cutting speed and cooling conditions. Therefore, to achieve high-speed cutting, the evaluation of the thermal shock and thermal crack resistance of the cutting tool is important. In this study, as a basis for improving the thermal shock resistance of brittle cutting tools during high-speed intermittent cutting from the viewpoint of cutting conditions, we focused on the cooling conditions of the cutting operation. An experimental study was conducted to examine the effects of noncutting time on thermal crack initiation. Thermal crack initiation was found to be restrained by reducing the noncutting time. In the turning experiments, when the noncutting time was less than 10 ms, thermal crack initiation was remarkably decreased even for a cutting speed of 500 m/min. In the milling operation, the number of cutting cycles before thermal crack initiation decreased with increasing cutting speed under conditions where the cutting speed was less than 500 m/min. However, when the cutting speed was greater than 600 m/min, thermal crack initiation was restrained. We applied the minimal quantity lubrication (MQL) coolant supply to the intermittent cutting operation. The experimental results showed that the MQL diminished tool wear compared with that under the dry cutting condition and inhibited thermal crack initiation compared with that under the wet cutting condition.
Effects of Cutting Fluid Application in the Performance of the Nimomic 80A Turning
Authors: Gama Renann Pereira , Ribeiro Marcos Valério
Published: July 2015

The increase of world requirements for improved products joined to growing competition between companies in the global market makes the same seek processes that ensure lower costs allied to high productivity and high quality product. Therefore, the great industrial and technological development has been increased the search for machining processes that promote, for example, high performance as regards the chip removal, less tool wear, failure and reduced impact on the environment. Regarding nickel-based superalloys, they have an extremely important role in the aeronautical and automotive industries among others. The nickel-based superalloy studied is the Nimonic 80A, hard machine material that has high mechanical strength and corrosion resistance on higher temperatures. The objective of this report is to study the influence of the application of cutting fluids in turning and the machining parameters in order to achieve high performance and optimization of machining this alloy. This one was machined using various machining parameters: cutting speed, feed rate, cutting depth, Minimum Quantity fluid (MQF), and Fluid abundant. After turning chip samples were obtained, was measured the surface roughness, volume of chip removed, cutting length and macro structural, some analyzes were performed and of lifetime of the tools were used in order to detect possible wear, as well as, microstructural observation of the chips by optical microscopy, scanning electron microscopy (SEM) and energy dispersive spectroscopy (EDS).On this report, we can observe the behavior of the materials and tools in the two cooling conditions used, and also, the impacts of the parameter variations in the surface finish, on the structure of the material and performance of the tools in respect chip removal regarding volume removed and machined length. Application by MQF was promising, but there is an abundant beyond the traditional application.
Evaluation of Grinding Performance by Mechanical Properties of Super Abrasive Wheel - Evaluation of Grade by Grinding Force
Authors: Sawa Takekazu , Nishikawa Naohiro , Ikuse Yasushi
Published: July 2015

There is the grade as one of the selection criteria of a grinding wheel like WA whetstone or GC whetstone. The grade of grinding wheel is defined as an index which shows the strength of connection of a grain and a grain, and is usually estimated by bending strength. There are many papers about the relationship between the grade of a grinding wheel and the grinding performance. And, the relationship between the grade of a grinding wheel and the grinding performance is almost clear. Also, the relationship between mechanical properties of a grinding wheel and the grade is also clear. On the other hand, since the grain layer of a super abrasive grinding wheel is thin, it is difficult to apply the conventional evaluation test of the grade. And, the evaluation method of the grade which can be adapted the super abrasive grinding wheel is not established. In addition, since the grade of a super abrasive grinding wheel is a manufacture manufacturer's original standard, there is a minute difference by manufacturer. The super abrasive grinding wheel as well as the grinding wheel is conjectured that the grade influences the grinding performance. Namely, it is important to relate the grade and the mechanical properties of a grain layer. However, researches which relate the grade, the grinding performance and the mechanical properties of a super abrasive grinding wheel are not done so far. Therefore, this study examined the relationship between the mechanical properties of a grain layer of a super abrasive grinding wheel and the grade, the grinding performance. The final objective of this study is to evaluate the grinding performance from mechanical properties of a grain layer of a super abrasive grinding wheel. The purpose of this report is to clarify relationship between the grade and the grinding force in a resinoid bond diamond wheel. The specific experiment procedure is as follows. When carrying out surface grinding of the diamond sticks using a grinding wheel, the relationship of the grade and the grinding force was clarified. And based on the knowledge acquired in this experiment, relationship between the grade of a super abrasive grinding wheel and the grinding force was considered. As the results, it confirmed that the grade of a resinoid bond diamond wheel could be evaluated by the grinding force.
Evaluation of Machining Forces in Asymmetrical Face Milling of Cast Iron DIN GGG50
Authors: Hübner Henrique Butzlaff , de Souza André João
Published: July 2015

The effects of the feed rate and the axial and radial depth of cut in the up and down asymmetrical face milling with respect to workpiece about the orthogonal components (axial, radial and tangential) of the cutting force in the machining of cast iron DIN GGG50 with carbide inserts was evaluated. The spindle speed was remained constant. The cutting forces were acquired through a sensory system that consists of piezoelectric dynamometer, signal acquisition board and computer with appropriate software. In the end it was concluded that studies of machining forces provides a strong basis for understanding the kinematics and the dynamics of the tool and the cutting operation and it can be applied to optimize the cutting geometries and test the probabilities of tool distortions.
Improving the Polishing Effect of Stainless Tube by Magnetic Finishing with Gel Abrasive
Authors: Wang A Cheng , Tsai Lung , Liu Chun Ho , Lin Yan Cherng
Published: July 2015

Magnetic abrasive finishing (MAF) is a fast and high-precision polishing method. However, the magnetic force acting on abrasive particles will decrease remarkably when polishing stainless steel tubes with the property of non-permeability, such as the SUS304 stainless steel. Moreover, the abrasive particles will be moved off the surface of machining area due to the centrifugal force of rotation, resulting in reducing the stability of polishing process. Therefore, this study developed a novel approach by adopting different gels as the bonding materials to combine the magnetic abrasive particles with hard abrasive particles to create a series of magnetic abrasive gels. Generally, those abrasive gels have higher viscosity to dominate the flow property that will constrain uniform motion of the abrasive particles in MAF, and the abrasive gels can be tightly contacted to the wall surface to increase the stability of polishing. This investigation utilized the optimal parameters out of Taguchi method to polish SUS304 stainless steel tube for 30 minutes—the value of surface roughness can be reduced from 0.636μm Ra to 0.05μm Ra, which can be improved by 92.1%, and the amount of material remove rate is as high as 218.4mg.
Machine Learning of Cutting Conditions in Drilling Using Artificial Neural Network
Authors: Xu Jie , Yamada Keiji , Sekiya Katsuhiko , Tanaka Ryutaro , Yamane Yasuo
Published: July 2015

Machining has traditionally been one of the major operations within most manufacturing systems and intelligent machining will play an important role in feature manufacturing systems. This paper concerns the machine learning, specifically classification and recognition of cutting conditions in drilling process. Awareness of the cutting conditions can enhance the auto-diagnosis of an intelligent machining system. In this paper, features representing the drilling process are generated from the converted forms of thrust force and torque and extracted with wavelet packet transform (WPT) and then selected by principal component analysis (PCA). Data instances are generated from experiments with different cutting conditions including workpiece material, drill diameter, feed rate, and spindle speed. A feed-forward network trained with back-propagation method (BPNN) is applied to distinguish between the patterns of each cutting condition. The different contributions of features and the recognition results of cutting conditions are discussed.
Effect of Added Cr3C2 on the Microstructure and Mechanical Properties of WC–SiC Ceramics
Authors: Nino Akihiro , Sekine Takashi , Sugawara Kazuhisa , Sugiyama Shigeaki , Taimatsu Hitoshi
Published: July 2015

WC–20 mol% SiC ceramics with added Cr3C2 were sintered at 1600°C with a resistance-heated hot-pressing machine. Dense WC–SiC ceramics containing 0.1–0.9 mol% Cr3C2 were obtained. Above 1.2 mol% Cr3C2, the relative density decreased with increasing Cr3C2 content. A small amount of a Nowotny-phase type (Mo5Si3C-type) product was formed by the addition of Cr3C2, and no Cr3C2-based solid solution was found. The WC–20 mol% SiC–Cr3C2 ceramics had very fine equiaxed granular WC grains because of inhibited grain growth of WC. The Young’s modulus of the WC–20 mol% SiC–Cr3C2 ceramics decreased with increasing Cr3C2 content because Cr3C2 has a much lower Young’s modulus than WC. Cr3C2 addition below 0.9 mol% increased the Vickers hardness from 20.9 to 23.0 GPa, but a larger added amount reduced the Vickers hardness. The hardness of the WC–20 mol% SiC–Cr3C2 ceramics and the WC grain size obeyed a Hall–Petch-like relationship, suggesting that the hardness was strongly controlled by the WC grain size. A higher fracture toughness, 6.4 MPa m1/2, was obtained for the ceramics containing a small amount of Cr3C2 than for the binder-free WC. The addition of 0.1–0.3 mol% Cr3C2 improved the fracture toughness without reducing the hardness.
Study on Ultrasonic Cavitation-Assisted Micro-Endmill Milling
Authors: Goto Daisuke , Maeda Yukio , Iwatsuka Kenichi , Kamiya Kazuhide , Tanaka Hideaki , Kato Kazuya , Yazawa Takanori , Suzuki Shinya
Published: July 2015

Micro-channel chips used in micro total analysis systems are attracting attention in medicine. In generally the photolithography technology used in semiconductor manufacturing is used to manufacture micro-channel chip Si-dies. However, this technology requires many processes, such as mask fabrication and the application of photoresist to a substrate as well as expensive clean room facilities. A micro-channel chip has a micro-groove 30–100 μm wide. This study examined how to form a fine groove by cutting with a micro-endmill, with the aim of shortening the window time and reducing the cost. This steel die requires high accuracy, for example, a burr area ratio of not more than 5% of the groove bottom area, a surface roughness of the side and bottom faces of less than 1μmRz, and a change in the sectional area of less than 1%. So, this study examines micro-endmill’s cutting conditions, for example cutting speed, feed per tooth, and axial depth of cut. In MQL (minimum quantity of lubricant) cutting, the early fracture occurs when cutting was began. The cause has bad removing of the chips in MQL cutting, it is considered that the chips of hardened work have been re-cut as the result. Therefore, this study applied ultrasonic cavitation to milling, in order to solve this subject. This report experimentally examined the cutting performance of ultrasonic cavitation-assisted milling. We obtained the following results. In cutting distance of 20 m, the burr of MQL cutting is generated more than 5%, on the other hand, the burr of ultrasonic cavitation-assisted milling is less than that. In ultrasonic cavitation-assisted milling, a tool wear and fracture can be decreased by improvement of removing chips and lubrication.
The Effect of Eccentricity of the Tool on the Surface Morphology of FSJ Joint
Authors: Deng Yong Fang , Zuo Dun Wen , Song Bo
Published: July 2015

An attempt is made here to join 2024 aluminum alloy plate by friction stir joining (FSJ) using tools with different eccentricity. Joint surface morphology was observed, and the sizes of both arc line spacing and flash were measured. Furthermore, study the effect of eccentricity of the tool on the surface topography of FSJ joint and analyze the formation of the joint surface topography. It is found that, the space trajectory of long axis of shoulder which formed by the eccentricity of the tool determine the morphology of the arc lines; the ratio between the feed speed and the rotation speed determine the arc line spacing; length of time that long axis of shoulder squeeze the edge of the joint line in the advancing side and the retreating side determines the size of flash in both sides of the joint line. Arc lines were regularly distributed in the joint lines and there are also regular texture structure distributed in the flash of each side. The flash in the advancing side is less than the retreating side. Increasing the amount of eccentricity, it has litter effect on the arc line spacing but will destroy the arc lines morphology in the joint surface and promote the formation of filamentous flash structure in the both sides of the joint.
Effects of Filler Compositions on Mechanical and Physical Properties of the Dissimilar Resistance Spot Welded between Aluminium Alloy and Carbon Steel
Authors: Purwaningrum Yustiasih , Triyono Triyono , Fathan Muhammad
Published: July 2015

The resistance spot weld (RSW) of dissimilar materials betweeen steel and aluminium is generally more complex than that of similar materials due to the extreme differences in the mechanical, physical and chemical properties of the base metals. This study proposed the use of filler material to connect the differences of their properties. Al-Alloy 5083 with thickness of 4 mm and 1.2 mm thick carbon steel SS400 were joined in lap joint types using RSW with the filler materials. The filler materials were a mixture of steel and aluminium in which weight composition variations (Fe:Al) were 90:10; 70:30; 30:70 and 90:10 in percent. The physical properties were examined based on the microstructure using optical microscope while the mechanical properties were measured with respect to the strength and hardness using Universal Testing Machine and Vickers Microhardness respectively. Results showed that weld metals with filler composition of 70:30% had highest shear-strength. The microstructure examinations showed that Microstructure of base metal and HAZ carbon steel was ferrite and perlite while that of weld metal was bainite. There were no significant differences in the microstructures and the hardness of weld metal, HAZ, and the base metal of aluminium alloy-5083 due to nonheat-treatable material.
Simulation of Cracking Behavior in Planar Solid Oxide Fuel Cell during Thermal Cycling
Authors: Anam Khairul , Lin Chih Kuang , Purnowidodo Anindito
Published: July 2015

Cracking behavior of positive electrode-electrolyte-negative electrode (PEN) assembly in a planar solid oxide fuel cells (pSOFC) during thermal cycling are investigated by using a commercial finite element analysis (FEA). The stress intensity factor for various combinations of surface crack size of 1 μm, 10 μm, and 100 μm and shape of semi-circular and semi-elliptical at highly stressed regions in the PEN are repeatedly calculated at room temperature and steady stage for twenty cycles. Simulation results indicate the stress intensity factor is significantly decreased at room temperature and is slightly increased at steady stage with increasing number of cycle. However, all the calculated stress intensity factors during thermal cycling in the present investigation are less than the corresponding fracture toughness given in the literature.
Modelling of Granular Solid-Structure Interaction: A Comparative Study Using Conventional FEM Approach and Linked DEM-FEM Approach
Authors: Ai Jun , Lin Chih Kuang , Chung Yun Chi
Published: July 2015

Interaction between granular solids and boundary structures is a fundamental problem encountered in bulk solids handling and subsurface structural design. Current understanding of its mechanism has not been adequate for robust and economical engineering designs, especially for flexible boundary structures. A classic and essential example is uniaxial compression of dry granules in a deformable cylindrical container, where the response of the confined granules under axial loading and the load transmission to the contacting structure still remain not fully understood. This paper comparatively studies such a confined compression scenario using a newly developed numerical procedure (Linked DEM-FEM) and a conventional FEM approach. The examined system involved around 7700 polystyrene beads contained in an acrylic thin-walled tube supported at one rim and gagged by two end platens. The compression was applied by displacing one end platen at a constant rate while fixing the other. Characteristics of the compression system, including load-displacement response, force transmission to boundary structure, mobilised bulk wall friction coefficient, and stress distribution on the wall, were evaluated. The majority of the compared physical quantities show reasonable to good agreement, thus giving a convincing quantitative verification for both approaches.
A Double-Sided In-Plane Lateral Comb-Drive Actuator Fabricated by a Plaster-Based 3D-Printer
Authors: Mizuno Jun , Takahashi Satoshi
Published: July 2015

In this paper, design, fabrication and characterization of a double-sided in-plane lateral comb-drive actuator fabricated by a plaster-based 3D-printer is described. The design is based on MEMS (Micro Electro-mechanical Systems) design concept. The movable part of the actuator consists of a (10x52.5) mm rectangular plate, and the end sides have depression areas in order to fit a (0.5x21.3) mm beam-shaped hinges. In the remaining sides of the plate, 18 comb fingers (0.5x10) mm are set at each opposite side. The stationary part of the actuator consists of 17 comb fingers with the same dimension to that of the stationary ones, and they are set at both sides of a frame and interdigitated with the movable comb fingers on the same plane. The gap between the movable and stationary comb fingers is 1.0mm. The structure thickness is 1.5mm. Such a structure, which both sides are provided with an in-plane interdigitated comb fingers, is called double-sided in-plane lateral comb-drive actuator. This actuator has been fabricated by using a plaster-based 3D-printer. Since plaster composite is an electrical insulating material, the structure has been suitably masked and the upper and lateral surfaces have been metallized thereafter by Au ion sputtering for the actuator electrodes formation. The hybrid fusion of 3D-printing manufacturing technology and MEMS-based design concept has been recently proposed by the authors and named as SMEMS (Sub-milli Electro-mechanical Systems), since the smallest possible fabrication size is in the order of sub-millimeters. The advantage of SMEMS technology is the quick and easy fabrication of 3D structures from 3D-CAD data. Furthermore, SMEMS is completely environment-clean since any hazardous chemicals or gases are used. The actuator has been driven by differential voltages, where both sides are biased at a voltage of 100V, and a 200 Vpp and its 180°shifted sinusoidal voltages are applied at each side. The actuator laterally moved by 96.8μm (full width) at a resonance frequency of 72Hz, and the mechanical quality factor has been estimated to be about 10.
Consideration of Interlock System Applicable to Pneumatic Driving Systems as the Safety System (BS/EN764-7)
Authors: Nakamura Mizuho , Okabe Masayuki , Sugimoto Noboru
Published: July 2015

The safety system is defined in BS/EN764-7(2002) (Safety systems for unfired pressure equipment) European Standard which is equipped with pressure releasing means (e.g, safety valve, reliefe valve, rapture disk). However, this safety system is not adequately functional as a safety system because the pressure releasing means cannot ensure the security for safe-side failures or degradation characteristics. In view of this, this paper presentation an interlock system applicable to pneumatic driving systems based on the safety (confirmation) principle. This system in the Safety-related parts (system) without giving (harm) the effects of hazardous side of error to stop the run of the load by the power source shut off from the possibility of hazardous side of error, it is practical there is no contradiction in ISO12100, ISO13849 international standard. The interlock system discussion about the suitability of the safety system defined in BS/EN764-7. As a result, the consideration for ensuring the reliability in “Safety of the control” by BS/EN764-7 is requested by adopting the safety system of the interlock system.
Dynamic Analysis of Offset Printing Press Gear-Cylinder-Bearing System under Time-Varying Meshing Stiffness Effect
Authors: Ou Yang Tian Cheng , Chen Nan , Ju Cui Cui , Li Cheng Long , Li Jiang Hu
Published: July 2015

This study propose a new nonlinear model for offset printing press gear-cylinder-bearing system by the lumped parameter approach. The multi-DOF model consists of helical gear pairs and spur gear pairs with time-varying meshing stiffness. Bearing and shaft flexibilities are include in the model as well. The equations of motion are obtained by Darren Bell principle and Runge-Kutta numerical method is used to slove the equations of motion. The results show that meshing stiffness and bearing stiffness significantly affect critical speed, vibration acceleration and meshing force. Multi-body dynamics software are applied to compare with lumped parameter model. The results show that there are many similarities in different aspects. Results of experimental study on offset printing press are also presented for validation of different models. After Discrete Fourier Transform, the graphics display that acceleration peaks frequencies are an integer multiple of the gear mesh frequency. It demonstrate that mechanical vibration is mainly from gear transmission system at high printing speed and gear transmission system lead to nonlinear vibration. This work provide a foundation for further improvement of the dynamics of gear system.
Fault Diagnosis Research for Mine Fan Based on the CFD
Authors: Fu Sheng , Du Xiao Fan , Luo Kan , Xu Yong Gang
Published: July 2015

In this paper, a new fault diagnosis method is proposed based on CFD technology in order to research the fault mechanism of mine axial fan. The method combined RANS equation and Realizable k-turbulence model realizes the three dimensional aerodynamic performance analysis of the fan impeller. Three-dimensional impeller model of axial fan was set up in three conditions which including normal, crack and blade loose, and comparing the turbulence characteristic of the three models. The research provides the theoretical basis for the fault mechanism of blade failure, and it has important reference value for fault diagnosis method based on CFD of mine axial fan.
Investigations of Cylindrical and Conical Whirl Instabilities on Hydrodynamic Journal Bearings
Authors: Miyanaga Norifumi , Tomioka Jun
Published: July 2015

Hydrodynamic journal bearings induced serious shaft vibrations called oil whirl. Since they often give severe damages to the mechanical systems, it is important to fully understand the phenomenon to avoid the occurrence by the proper bearing design. This study theoretically and experimentally investigated both cylindrical and conical whirl instabilities, which can be appeared in journal bearings, and their relation was discussed. As the result, the span length of the bearings had a significant effect on the vibration mode. The transitional state in which the cylindrical and conical whirl instabilities alternately appeared was observed.
Cylindrical Gears with Increased Contact Area – Proposal of Application in Watercrafts Power Transmission Systems
Authors: Batsch Michał , Markowski Tadeusz , Homik Wojciech
Published: July 2015

Paper presents the method for obtaining maximum contact pressure of Novikov gears. Described surface strength calculation method is based on Hertz theory of two bodies being in point contact. What’s more the influence of gear position errors on maximum contact stresses has been presented. Also the comparison of Hertz stresses for Novikov and involute gears has been made.
Spectrophotometric Determination of Cefixime Trihydrate in Pharmaceutical Formulations Based on Ion-Pair Reaction with Bromophenol Blue
Authors: Keskar Mrudul R. , Jugade Ravin M.
Published: July 2015

Cefixime trihydrate is a broad spectrum cephalosporin antibiotic, effective against gram-positive and gram-negative bacterial infections. Simple and rapid method has been developed for the determination of cefixime trihydrate in bulk and pharmaceutical formulations. This method was based on the formation of bluish-green ion-pair complex of cefixime trihydrate with bromophenol blue in dimethyl sulfoxide (DMSO)–acetonitrile medium. Different parameters were studied and optimized. A 2:1 complex was formed between the drug and reagent almost instantaneously at room temperature which has δmax of 610 nm. Under optimum conditions, calibration curve was found to be linear over the range of 10-130 µg mL-1. The method was subjected to analytical quality control. The limit of detection was found to be 1.08 µg mL-1. Recovery studies and interference studies were carried out. The proposed method was successfully applied to the determination of cefixime trihydrate in bulk and pharmaceutical formulations with high precision and accuracy.
An International Observational Prospective Survey Assessing the Control of Atrial Fibrillation in Asia-Pacific: Results of the Record-AFAP Registry
Authors: Amerena John , Chen Shih-Ann , Sriratanasathavorn Charn , Cho Jeong-Gwan , Dejia Huang , Omar Razali , Fat Tse Hung , King Anthony
Published: July 2015

A prospective 1-year observational survey was designed to assess the management and control of atrial fibrillation (AF) in eight countries within the Asia-Pacific region. Patients ( N = 2,604) with recently diagnosed AF or a history of AF ≤1 year were included. Clinicians chose the treatment strategy (rhythm or rate control) according to their standard practice and medical discretion. The primary endpoint was therapeutic success. At baseline, rhythm- and rate-control strategies were applied to 35.7% and 64.3% of patients, respectively. At 12 months, therapeutic success was 43.2% overall. Being assigned to rhythm-control strategy at baseline was associated with a higher therapeutic success (46.5% vs 41.4%; P = 0.0214) and a lower incidence of clinical outcomes (10.4% vs 17.1% P < 0.0001). Patients assigned to rate-control strategies at baseline had higher cardiovascular morbidities (history of heart failure or valvular heart disease). Cardiovascular outcomes may be less dependent on the choice of treatment strategy than cardiovascular comorbidities.
Are Motor Skills and Motor Inhibitions Impaired in Tourette Syndrome? A Review
Authors: Kalsi Navkiran , Tambelli Renata , Aceto Paola , Lai Carlo
Published: July 2015

Tourette syndrome (TS) is a neurodevelopmental motor disorder described as an inability to inhibit unwanted motor movements. This article reviews research on the execution and inhibition of voluntary motor movements in TS. Over last two decades, a number of studies have addressed the structural and functional deficits associated with this syndrome. Only a limited number of studies have assessed the motor skills in these patients but have failed to reach any conclusive outcome. In the domain of response inhibition also, studies have reported arguable impairments in these patients. It is suggested that these conflicting results can be attributed to co-occurring comorbid conditions, the constraints posed by variable age groups, lack of control measures, and lack of specificity of domains addressed. This review will describe a way in which future research can be directed to increase our knowledge of this otherwise complex spectrum of disorders.
A state-and-transition model of Iberian dehesas based on spatial patterns
Authors: Caballero Jesus , Felicísimo Ángel M. , Quirós Rosado Elia
Published: July 2015

Aim of study: In this study a process based on a Geographic Information System (GIS) is proposed as a tool for analyzing the spatial structure of the Mediterranean dehesa ecosystem.Area of study: Western Peninsular Spain.Material and methods: The method allows a semi-quantitative “state and transitions” (S&T) net that provides original information derived from spatial patterns that cannot be obtained by other means.Main results: This GIS analysis also supplies a spatial basis which complements the conceptual framework of vegetation series successional proposals. Moreover, the proposed method can be a useful tool for understanding landscape changes.Research highlights: Our work proposes not only a descriptive model but also a methodology based on spatial metrics and topological relationships.Keywords: geographic information systems; successional net; landscape management.Abbreviations used: S&T: State and Transition; RFP: Regional Forest Plan.
Incorporating economic valuation into fire prevention planning and management in southern European countries
Authors: Varela Elsa , Soliño Mario
Published: July 2015

Aim of study: This article describes and analyzes the links between the fire-based scientific knowledge, the social perception of fire prevention and forest fires and the economic valuation requirements to assess social preferences for fire prevention measures.Area of study: Southern European countries.Material and Methods: For that purpose, we develop a critical revision of the existing literature on economic valuation of social preferences for fire risk reduction and fire prevention in terms of its links with fire science and social perceptions and the applicability of these results in fire management policies.Research highlights: The assessment of social preferences for fire related issues is challenging due to the difficulty of setting sound valuation scenarios that can simultaneously be relevant for the respondents and derive conclusions useful for fire management. Most of the revised studies set up valuation scenarios focused on the final management outcome e.g. number of burnt hectares, what is easier for the respondents to evaluate but weakens the scientific relationship with fire management, making difficult reaching conclusions for sound management advice. A more recent set of valuation studies have been developed where risk perception of homeowners is further assessed as a key variable determining their preferences in valuation scenarios. These studies are relevant for mangers setting fire prevention programs in wildland urban interface areas as understanding the factors that may promote or hinder the enrolment of these homeowners in fire prevention activities may have direct implication in addressing communication programs to promote fire prevention management.Keywords: fire prevention; fire risk reduction; economic valuation.Abbreviations used: WTP- willingness to pay; CV- contingent valuation; CM- choice modelling.
Characterization of functional SSR markers in Prosopis alba and their transferability across Prosopis species
Authors: Pomponio María F. , Acuña Cintia , Petreath Vivien , L. Lauenstein Diego , M. Poltri Susana , Torales Susana
Published: July 2015

Aim of study: The aim of the study was to characterize functional microsatellite markers in Prosopis alba and examine the transferability to species from the Prosopis genus.Area of the study: samples were obtained from natural populations of Argentina.Material and Methods: Eleven SSR functional markers related to stress and metabolism were amplified in a sample of 152 genotypes from P. alba, P. denudans, P. hassleri P. chilensis, P. flexuosa, and interspecific hybrids.Main results: In P. alba, the PIC average value was 0.36; and 6 out of the 11 primers showed high values of polymorphism ranging from 0.40 to 0.71. The cross-species transferability was high with high percentages of polymorphic loci.Research highlights: The SSR markers developed in P.alba were easily transferred to other Prosopis species which did not have functional markers.Keywords: genetic variation; functional markers; microsatellites; prosopis.Abbreviations: PIC: Polymorphic Information Content; PCR: Polymerase Chain Reaction; SSR: Simple Sequence Repeat.
Perceptions of health workers regarding the occupational health services rendered at Onandjokwe hospital, Namibia
Authors: HJ Amukugo , K Amakali , K Sipa
Published: July 2015

Objective: Health care workers are exposed to a variety of health hazards in their daily work. This exposure puts them at risk of acquiring occupational related diseases, including psychological stress, which can lead to mental illness, absenteeism and job dissatisfaction. In view of the potential risks and occupational hazard, a comprehensive health and safety programme for all employees is mandatory to minimize injury among the employees and therefore for the institution to fully harness the potential of its employees. The programme should indicate management goals, objectives and policy implementation, as well as responsibility and accountability for each role player. The aim of this study was to determine the challenges facing health workers regarding the occupational health services (OHS) at Onandjokwe Hospital in Northern Namibia. The objectives of the study were to determine the existing situation relating to the OHS rendered at Onandjokwe Hospital and to explore and describe the perceptions of health workers regarding OHS at the hospital.Methods: The study employed both quantitative and qualitative methodology that included the use of a checklist for collection of quantitative data on evidences of practice of OHS in different departments of the hospital; interviews and focus group discussions for collection of the data on the workers’ perception on OHS in the hospital. Epi-info software version 3.5.1 was used to analyses the quantitative data while Tech’s method of qualitative analysis was used for the qualitative data.Results: The study revealed that the provision of OHS in the hospital was extremely limited. Many key documents guiding the provision of effective OHS were found to be lacking in several hospital departments. Limited training had been conducted and as a result, there was low awareness on OHS among the employees in the hospital. Both management and staff cited lack of key personnel to drive the process as an important impediment to strengthening OHS in the hospital.Conclusions: The main recommendations that arose from the research include the need for the hospital management to comply with the guidelines on Occupational health, acquire and avail key guiding documents for occupational health practice in all the departments; provision of necessary resources for OHS including OHS staff and implementation of OHS programme to safeguard the health of the employees.
Influência do ângulo de plantio sobre a brotação e o enraizamento de estacas de Phyllanthus sellowianus (Klotzsch) Müll. Arg.
Authors: Monteiro Josita Soares , Leite Michele Benetti , Wink Charlote , Durlo Miguel Antão
Published: July 2015

A estabilização de encostas naturais ou artificiais de terrenos e margens de cursos de água é possível com a aplicação de técnicas propostas pela engenharia natural ou bioengenharia de solos, que utilizam a vegetação, sozinha ou combinada com materiais inertes. Para isso, a vegetação a ser empregada necessita preencher alguns requisitos relacionados a aspectos ecológicos, fitossociológicos e de reprodução. As técnicas de engenharia natural utilizam as plantas em diferentes posições em relação à horizontal. Por essa razão, o presente trabalho tem por objetivo avaliar os efeitos de diferentes ângulos de plantio de estacas de Phyllanthus sellowianus (Klotzsch) Müll. Arg. para a estabilização de taludes. Com isso, será possível sugerir a forma mais adequada para o plantio dessa espécie, ou seja, em quais práticas biotécnicas esta pode ser melhor utilizada. O experimento foi conduzido no Viveiro Florestal, na Universidade Federal de Santa Maria (UFSM), Santa Maria, RS, no período de agosto a novembro de 2007. Os tratamentos consistiram no plantio de estacas de Phyllanthus sellowianus (Klotzsch) Müll. Arg., em três ângulos diferentes (10°, 30° e 90°). As estacas foram coletadas na região central do estado do RS e confeccionadas com 30 cm de comprimento (± 1 cm de variação), com diâmetro médio de 1,9 cm. Dois terços de sua base foram inseridos em substrato inerte (areia). O delineamento experimental foi o inteiramente casualizado, com trinta repetições (estacas) por tratamento. Após 90 dias foram analisados as seguintes características: sobrevivência das estacas, número, comprimento e diâmetro dos brotos e raízes primárias, além da massa seca das raízes e brotos. A espécie apresentou altos valores de sobrevivência, com tendência de maiores resultados em estacas plantadas em ângulos de 10° e 90°. O plantio de estacas em ângulo de 90° também proporcionou os maiores valores da soma de comprimento e da massa seca dos brotos, enquanto que o diâmetro e o número de brotos não apresentaram diferenças significativas entre os ângulos de plantio. O número, a soma do comprimento e a massa seca das raízes, tiveram valores significativamente maiores em estacas plantadas em ângulo de 90°. O diâmetro da raiz mais longa apresentou maior média em estacas plantadas em ângulo de 10°, enquanto que o valor médio do comprimento da raiz mais longa por estaca não mostrou diferença estatística entre os três ângulos de plantio.
Plantio misto de Eucalyptus urograndis e Acacia mearnsii em sistema agroflorestal: I - Produção de biomassa
Authors: Kleinpaul Isabel Sandra , Schumacher Mauro Valdir , Viera Márcio , Navroski Marcio Carlos
Published: July 2015

Objetivou-se com o presente estudo quantificar a biomassa de um plantio misto de Eucalyptus urograndis e Acacia mearnsii em sistema agroflorestal com milho (Zea mays L.) no município de Bagé, RS. O delineamento utilizado foi blocos ao acaso com cinco tratamentos e três repetições (T1- 100E; T2-100A; T3-50E:50A; T4-75E:25A e T5-25E:75A), com espaçamento de 4,0 m x 1,5 m. Foram plantadas três linhas de milho, entre as fileiras de eucalipto e/ou acácia-negra. Aos 10 meses de idade, foi quantificada a biomassa das espécies florestais, que foram separadas por frações (folha, galho e tronco). A biomassa do milho foi coletada no final do ciclo e também separada por frações (folha, palha, grão, sabugo e colmo). Em plantio misto o tratamento T5 (25E:75A) apresentou o maior acúmulo de biomassa, sendo 35,1% nas folhas, 25,8% nos galhos e 39,1% no tronco. A acácia-negra apresentou maior crescimento inicial do que o eucalipto, tanto em monocultivo como em plantio misto. A produtividade do milho ficou entre 1,01 a 1,26 Mg ha-1, não diferindo estatisticamente (p > 0,05) entre os tratamentos.