bluuebunny/crossref_metadata_2025 huggingface dataset:
Analysis of the Feasibility of Usage of Standalone Controllers for Control of Spark-Ignition Engines
Authors: Wierzbicki Sławomir , Kraskowski Wojciech , Kolator Bronisław
Published: January 2016

Modern combustion engines have developed into technologically advanced units that are controlled by complex electronic systems. The controllers of these systems are equipped with built-in control algorithms which allow the engine to achieve optimum engine performance parameters, in compliance with the strict requirements of standards related to the release of toxic fumes to the atmosphere. Unfortunately, this type of engine control system very often makes it difficult to carry out research, or even prevents it, because the change of engine's regulatory parameters is not possible. Currently in most cases research carried out on this type of engine requires the construction of special controllers that allow the user to interfere with the performance of the control system. This article presents the results of tests carried out on an ignition-type engine controlled by a standalone engine.
The Ongoing Assessment of the Technical Condition of Avionic Hydraulic Drives on the Basis of Information Received from Means for Unbiased Flight Control of Aircrafts
Authors: Ułanowicz Leszek
Published: January 2016

During the ongoing operation of the hydraulic system you need a drive control information capable of maintaining fitness. Existing methods for assessing the technical condition of the hydraulic system require dismantling the hydraulic units and their research on test rigs. These methods are expensive, time consuming and do not provide a quick assessment of the technical condition. The aim of the study is to present the possibilities of using the evaluation of technical aviation hydraulic drive method which involves the use of objective information from the aircraft's flight control. In the proposed method, the carrier of information to the ongoing evaluation of the technical condition of the hydraulic system aviation as a whole is the pressure prevailing in it. With pressure and its features is inextricably bound up time. This relationship may be obtained directly from the objective flight control of the aircraft. The greatest credibility and the diagnostic value of two control parameters are obtained from the flight control objective. The first time the air pressure drop in the hydraulic drive from the top to the bottom of the measured value of the measured value after switching off the power unit. The second time the pressure falls below a certain value, and its return to the values ​​of the movement during the hydraulic motor. The method enables the ongoing assessment of the technical condition of the hydraulic system is a fast and costless.
Measurement of Hydroacoustic Channel Impulse Response
Authors: Studański Ryszard , Zak Andrzej
Published: January 2016

The article describes the method of determining the hydroacoustic channel impulse response using signals modulated by pseudo-random sequence. Moreover, exemplary impulse responses determined in the laboratory conditions were presented.
Analysis of WiFi Communication (Data Interchange) for Mobile Robot in Industrial Environment
Authors: Ostrowski Igor , Szulewski Piotr , Masłowski Andrzej
Published: January 2016

Wireless network used in office is much cheaper than industrial-type devices. Using of office-type WiFi communication in industrial environment for exchange data between mobile platform (AGV) and base station is the core of this paper. The scope of research is data limitation flow in function of distance between system nodes and usability of office-type (low cost) equipment for establishes stable communication on industrial environment. Paper describes two experiments in two types of production environment. First one was realized in condition where several disturbance sources were active (like metal forming machine-tools, constant energy welding machines, electric overhead crane, high power electric motors, electronic inverters etc. All this machines contaminate radio environment around them and make serious obstacles for WiFi data exchange. Second experiment was executed in assembling hall of automobile production plant in which radio contamination is significantly lower.
Assessment of Series Compensator for Ferroresonance Damping in Power System
Authors: Khavari Amir Hesam , Abdul-Malek Zulkurnain , Wooi Chin Leong
Published: January 2016

Nowadays power quality is a critical issue in power system. Moreover the connection of three-phase transformers through underground cables is growing fast in residential, commercial, industrial and rural applications. Due to this increasing situation, the possibilities of having a series connected capacitance and a non-linear inductance, and hence ferroresonance, become more probable. Ferroresonance can also occur in power transformers or reactors by capacitive coupling from neighbouring phases or lines. It is necessary to have a general idea about what would be the best preventive decisions to take in order to avoid unexpected surprises. It is necessary to have an accurate ferroresonance model so that a device that can smoothen the sharp effects of ferroresonance can be found. In this paper, the FACTS device, namely the static synchronous series compensator (SSSC) had been used to mitigate ferroresonance. Results show that using SSSC dramatically decreases and mitigates the ferroresonance shock as well as the instabilities of the network.
Simulation and Analysis of RC Type Relaxation Power Generator for Electrical Discharge Machines (EDM) in Laplace Transform
Authors: Karimi Pour Fatemeh , Bavandi Mahrokh , Yahya Azli
Published: January 2016

Electrical discharge machining (EDM) is one of the earliest non-traditional machining processes and controlled process where pulsed electrical discharge is used to erode metal in a workpiece. EDM pulsed power generator applies voltage pulse discharge occurs in a small gap between the work piece and the electrode and removes the unwanted material from the parent metal through melting and vaporization. The essential requirement for EDM system is to obtain the output waveform similar to the ideal EDM waveform. This paper seeks to discuss on the design and simulation based on RC (resistance-capacitance) power generator circuit. Based on the findings of the study, from the equation gained, the simulation is constructed through using electrical model in Matlab Simulink software and circuit analysis in Lapels transform in EDM system process. Also this procedure simulated in Matlab software.
Cloud-to-Ground Lightning in Malaysia: A Review Study
Authors: Wooi Chin Leong , Abdul-Malek Zulkurnain , Ahmad Noor Azlinda , Mokhtari Mehrdad , Khavari Amir Hesam
Published: January 2016

Lightning has been the major cause of power interruptions in Malaysia. Malaysia is located near the equator having approximately 200 thunder days per year. It is known to be among the highest lightning activity country worldwide. TNB as the main power supply utility in Malaysia has made an effort to reduce the power interruptions via installation of Lightning Detection Network (LDN) in 1994. This paper presents the history leading to modern LDN that capture lightning radiation fields at multiple remote sensors. The network has undergone a series of improvement between 2004 and 2009 in response to evolving detection technologies and requirements. Recent analyses on actual performance of the current LDN are also summarized. The paper includes short and long term requirements for improving the lightning measurements needed to address some open scientific questions and fill the needs of emerging applications.
A Systematic Approach to Safe and Effective Earthing System Design for High Voltage Substation
Authors: Kamal Ahmad Shukri A. , Arief Yanuar Z. , Sidik Muhammad Abu Bakar
Published: January 2016

In high voltage substation, earthing system is an essential part not only for providing the protection to people who are working or walking in the vicinity of earthed facilities and equipment against the danger of electric shock, but also for maintaining the proper function of the entire electrical system. By selecting a proper conductor and electrode size based on standard criteria, the existence of large potential differences during fault or lightning conditions will able to be avoided. Standard equations for earthing are used in the design to obtain the desired parameters such as tolerable touch and step voltage, earth resistance, grid resistance, minimum size of earthing conductor and electrode, as well as resistivity of soil. Therefore, it would enable the establishment of the safe limits of potential differences under both normal and fault conditions. The main objective of this research work is to perform a necessary background information pertinent step by step approach for safe and reliable earthing system design for high voltage distribution substation in Malaysia. It including a set of applicable standard to be used as well as demonstrate an earthing design simulation developed using Microsoft Excel auto mathematical functions. The case study for high voltage substation design and simulation at two locations with different soil resistivity and properties is also performed in this research work. The results revealed that the design of high voltage substation earting system is much dependent on the property and resistivity of soil where the substation will be constructed.
An Economic Assessment of Hybrid Renewable Energy for a Remote Area Electrification in Iran
Authors: Khavari Amir Hesam , Abdul-Malek Zulkurnain , Moradi Mehdi , Tavalaei Jalal , Abdolahzadeh Anbaran Sajjad , Wooi Chin Leong
Published: January 2016

The utilization of renewable resources is growing, in part due to the environmental impacts caused by fossil fuels. The largest sources of renewable energy are wind and solar and many predict that these energy sources will be increasingly used for distributed generation. In this paper, the feasibility is examined of a grid-independent system applied for a remote area electrification in Binalood, Iran. Traditional power systems for remote or rural areas are based on fossil fuels. After addition of renewable energy resources, solar energy applications have become popular in remote energy systems. The recent study and research works show that adding other possible renewable energy resources such as wind, hydro and biomass could make a hybrid system more cost-effective and environmentally friendly. Hence, in the present study, an overview of applied hybrid renewable energy system (HRES) for worldwide villages with special attention on Iran has been proposed to help present and future works for better achievement in this field. Furthermore sensitivity analyses are performed to determine the impact on performance of several key parameters: wind speed and fuel costs. HOMER was used to evaluate the feasibility of various hybrid systems. The results of a comprehensive feasibility data analysis along with its economic evaluation indicate that the wind-diesel hybrid system with battery storage is most efficient energy system for supplying this remote area's electrical energy demands.
Development of Remote Operation System on Residential AC Power Supply Using Radio Frequency
Authors: Aris Azuan , Arief Yanuar Z. , Yiew Lau Kwan , Muhamad Nor Asiah
Published: January 2016

This paper deals with the development of a remote operation system for residential AC power supply using medium radio frequency transmission. Application of this system is to disconnect and reconnect the electricity supply which is operated by power utility company. Radio frequency (RF) remote control consists of a transmitter and receiver, which is the main module of the developed system. The transmitter will send a control signal through the module equipment transmitting antenna and the signal will be received by the antenna radio frequency transceiver module. Then, the recipient will control the electrical signals through the contactor as an interface with all electrical equipment. The operation of this system is at a fixed frequency of 315 MHz and distance control of electrical equipment is up to 10m at open space and subject to any restriction, antenna and supply of power. The results of this system are successfully demonstrated in the prototype of the remote control system for residential AC power supply. Some modifications have been proposed to improve the function of remote control system.
Thermal Analysis of Dammar Resin with Differential Scanning Calorimetry Method
Authors: Jamal  , Wardana I.N.G. , Hamidi Nurkholis , Widyanuriawan Denny
Published: January 2016

The benefit of dammar resin as an alternative renewable energy sources can be optimized by knowing the thermal characteristics. The purpose of this study is to perform thermal analysis of dammar resin. The differential scanning calorimetry (DSC) methods have been used to do this analysis. The results obtained indicate that the dammar resin has a melting temperature of 70.88 °C and 303.02 °C evaporation temperature, dammar resin also has a melting enthalpy of 7.6041 J/g and the enthalpy of vaporization 55.0395 J/g.
Pressure Drop of Two-Phase Flow Boiling with R-22 and R-290 in 7.6 mm Diameter Tube
Authors: Pamitran Agus Sunjarianto , Nasruddin  , Ardiansyah Helmi Dadang , Alhamid Muhammad Idrus
Published: January 2016

The characteristics of two-phase flow boiling of R-290 are required for replacing R-22 that has been phased-out. The present study focuses on experimental pressure drop for R-22 and R-290. The experiment was run with heat flux of 5.09 kW/m2 to 19.03 kW/m2, mass flux of 114.91 kg/m2s to 751.74 kg/m2s and saturation temperature of 4.77°C to 18.12°C. The present result showed that pressure drop was affected by heat flux, mass flux and saturation temperature. Lower mass flux, heat flux and saturation temperature results in lower pressure drop. The pressure drop of R-290 is lower than that of R-22. Among the existing pressure drop prediction methods, Lokhart-Martinelli (1949) gives the best prediction for the present pressure drop data.
Adapting Temperate Crops to Tropical Lowland through Solar Thermal Chilled Water Soil Cooling Process
Authors: Rasaq Adekunle Olabomi , Jaafar Abu Bakar , Musa Md Nor , Saad Amir A.
Published: January 2016

The availability of most temperate crops is a function of changing season. Thus, their insufficient global supply and consequent seasonal do cause increase in prices. The effect is more pronounced in the tropical countries that too depend on importation of these crops because of unfavorable soil condition to cultivate them (due to high soil temperature). Growing these crops in the tropics requires soil temperature to be as low as it is in the temperate climate. Soil cooling with chilled water from the combined organic rankine and absorption refrigeration cycles presented in this paper aims at utilization of virtutl “free” solar thermal energy as input to run combined organic rankine and absorption refrigeration plant and producing chilled water as output for soil cooling process. The technical feasibility is established based on the overall value of coefficient of performance (COP) and the estimated area of solar collector per unit cooling load while the economic viability is established based on capital and operating costs to be incurred per unit cooling load.
Adsorptive Removal of Chromium (VI) Ions Using Cryogel Derived from Oil Palm Fronds’ Lignin
Authors: Rusli Nur Shahirah , Ngadi Norzita
Published: January 2016

Nowadays, lignin is of special interest since it is the second most abundant biopolymer after cellulose. Given its extremely low cost and phenolic nature, lignin had become one of the leading candidates for preparing aerogels. However, production cost of carbon aerogels are considerably high due to extremely expensive supercritical drying method employed. Thus, carbon cryogels has been introduced by replacing the supercritical drying with freeze drying technique. In this study, lignin was extracted from dried and grinded oil palm fronds to be used as precursor for sol-gel polycondensation. Cryogel derived from oil palm fronds (OPF) was investigated as a suitable adsorbent for the removal of metal ions especially chromium (VI) through adsorption process. In addition, the adsorption amount was greatly increased when this cryogel was prepared with addition of ultrasonic effect instead of normal heating during the sol-gel polycondensation process. This new cryogel seems to be very promising for cost-effective treatment of heavy metals removal since the preparation is easy and being derived from a widely available and low-cost biomass feedstock.
Cellulose-g-PAM Derived from Kenaf for Ethyl Orange Removal
Authors: Mohamed Razak Siti Fatimah , Ngadi Norzita , Arsad Nurul Jannah
Published: January 2016

A novel hybrid flocculant of acrylamide and cellulose was synthesized by using microwave irradiation method. Cellulose was extracted from kenaf by using TAPPI method. 57.4% of percentage grafting and efficiency has been obtained from the grafting process. There are additional peaks that appeared in FTIR spectroscopy analysis that show PAM was grafted into cellulose backbone. The flocculation behavior was studied by using ethyl orange wastewater. The result shows that hybrid flocculant (cellulose-g-PAM) has potential to be used as flocculant in treating dyes waste water.
Preparation and Characterization of Textile Sludge-Based Activated Carbon for Dyes Removal
Authors: Najlaa Yac’cob Nurul Atiqah , Ngadi Norzita , Abd Rahman Roshanida
Published: January 2016

An activated carbon derived from textile sludge was synthesized as an initiative of low cost adsorbent for removal of dyes. The surface area of this activated carbon was determined by Brunauer, Emmett and Teller (BET). From the BET results, it shows a high increment in the BET multi point area for textile sludge-activated carbon as compared to the textile sludge, which is 623.9557 m2/g and 58.9806 m2/g, respectively. The effects of initial adsorbent dosage were studied in the removal of Reactive Black 5 (RB5) and Methylene Blue (MB) dyes. RB5 and MB dyes solutions were used to represent anionic and cationic dyes respectively. It was concluded that the adsorbent dosage was proportional to the dyes removal for both RB5 and MB with percentage removal up to 99%.
Control of Natural Convection Flow for Optimize the Performance Solar Dryers
Authors: Jamal
Published: January 2016

The purpose of this research to optimize the performance of solar dryers. Optimizing the performance of solar dryers can be done by observing the effect of natural convection flow controls to change the performance of solar dryers. Experimenting performed by the direct measurement method. In the solar dryer made in space collector inlet and outlet of the drying chamber. There are two outlet on the bottom and the top of the drying chamber. Natural convection flow control is done by adjusting the three variations (full open, half open and full close) openings on the upper outlet of the drying chamber. For the most accurate results, testing was conducted simultaneously three kinds of variations of openings using three solar dryers. The results show that optimal conditions of the solar dryer is in the half open position of the outlet flow natural convection.
Numerical Study of the Thermal Behaviours of the Absorbent Bed for Storing a Natural Gas at Adsorbed State with Low Pressure in a Vessel
Authors: Ybyraiymkul D.T. , Kaltayev A. , Ng Kim Choon
Published: January 2016

Energy and environmental problems of the economy in the world, especially in metropolitan areas caused by vehicles, is now becoming important and one of the main ways of solving this problem is using natural gas. Widespread use of gaseous fuel is heavily restricted by its storage problem in container under high pressure (20-25 MPa) in a gas state or at low temperatures (-163 ° C) in a liquid state. And the most promising solution of this problem is to develop a vessel based on of adsorption technology, which is designed for efficient storage of natural gas at moderate pressures (2-3.5 MPa).
Single-Line to Ground-Fault Detection for Unit Generator-Transformer Based on Wavelet Transform and Neural Networks
Authors: Sultan Ahmad Rizal , Mustafa Mohd Wazir , Saini Makmur
Published: January 2016

This paper proposes an approach for the detection of the single line to ground fault on a unit generator-transformer, based on the extraction of statistical parameters from wavelet transform based neural network. In the simulation, the current and voltage signals were found decomposed over wavelet analysis into several approximations and details. The simulation of the unit generator-transformer was carried out using the Sim-PowerSystem Blockset of MATLAB. The statistical parameters analysis involved measurement of the dispersion factors (range and standard deviation) of wavelet coefficients. Regarding the pattern recognition of neural networks performance, the accuracy of SLG-fault detection of neural networks was 97.45 %. The results indicated that dispersion factor feature of wavelet transforms was accurate enough in distinguishing a single line to ground-fault and normal condition for a unit generator-transformer.
Review on Dissolved Fault Gases in Monitoring Bio-Oil Filled Transformer
Authors: Ab Ghani Siti Soleha , Muhamad Nor Asiah
Published: January 2016

The combination of solid insulation (usually cellulose paper) and liquid insulation (usually mineral oil) yield good dielectric properties at fair cost. However, arising concerns on environmental effect of mineral oil when leakage and its risk of fire has force researches for alternative fluids. One of the suitable options for replacement of mineral oil is biodegradable oil that is plant-based, high biodegradability, non-toxicity and high fire point. Some refining and modification to crude vegetable oils resulting to suitable transformer dielectric fluid such as BIOTEMP®, ENVIROTEMP® FR3 and PFAE (palm fatty acid ester). Application of these oils in small scale distribution transformers give positive feedback so far, hence, led to development of biodegradable oil-based large power transformer. Monitoring of the oil for power transformer is important to ensure its reliability and avoid unnecessary cost of failure. Dissolved Gas Analysis (DGA) is one of the methods for oil monitoring of transformer. This method analyzes oil condition to detect incipient faults so that relevant actions can be made before actual failures occur. This paper will review the hydrocarbon gases or known as faults gases for monitoring and faults diagnosis for mineral and biodegradable oil-filled transformer. Past works about DGA on biodegradable oil such as sunflower, soybean, and corn oil are analyzed. Any different on gases production of oil through different tests will be discuss further in this paper.
Nonlinear Resonance Suppression as Distorting and Saturating Source in Voltage and Current of Power Transformer: UPFC and STATCOM Performance Evaluation
Authors: Tavalaei Jalal , Abdul-Malek Zulkurnain , Khavari Amir Hesam , Naderipour A.R.
Published: January 2016

Non linear resonance usually resonates in network which is consisting of ferromagneticcore. When distributed capacitance calculated form circuit breaker; mainly circuit breaker and cablecapacitance; after switching and opening the network feed apparatus, magnetization current on ferromagnetic core jump to saturation. Duration of ferroresonance is deeply relying on capacitance, and itwill be decaying by disembarking total store energy. Although, ferroresonance commence by switching circuit breaker off; protecting relay and other protecting schemes have no reaction, because thelast protection step for saving a device is a circuit breaker. There is no reported method to mitigatedisruptive phenomenon; which elder publication focus on the explosion of capacitive transformer,melting of power transformer core lamination and arresters problem. This work is tried to dampingferroresonance and reducing devastation effect on the apparatus. While, protecting devices is useless,fault point topology mutating by FACTS to control and decrease this phenomenon. FACTS deviceis settled at the upstream of apparatus to improve power quality, is switched on at initiating momentresonating. Modeling and simulating of ferroresonance are done by the actual value of transformerand other power system related devices extracted by UTM-TNB.
Reduction of Vibrations due to Unbalance with Anti-Vibration Clearance Angle in High Speed Milling
Authors: Thouvenin Anna , Li Xin , He Ning , Li Liang
Published: January 2016

High speed milling is one of the most commonly used machining processes in many fields of the industry. It is regarded as a simple and fast solution to achieve a high material removal rate, which allows an important production of parts. Unbalance is a problem in any machining process but becomes a considerable problem when reaching high speed machining. The vibrations due to an unbalanced tool or tool holder can result in a poor surface quality and a damaged tool. The damping of the vibrations can be achieved with a specially designed tool showing an anti-vibration clearance angle. This paper shows the influence of the anti-vibration clearance angle by a computational model and a set of experiments to see if it can reduce or suppress the vibrations due to unbalance in high speed milling.
Comparison between EBM and DMLS Ti6Al4V Machinability Characteristics under Dry Micro-Milling Conditions
Authors: Rysava Zdenka , Bruschi Stefania
Published: January 2016

This paper is aimed at evaluating the micro-machinability of the Ti-6Al-4V titanium alloy made by the means of two different Additive Manufacturing (AM) technologies. AM comprises promising technologies, widely used especially to produce parts made of difficult-to-cut materials, such as the titanium alloys. Titanium alloys represent one of the most widely used materials in the biomedical field, thanks to the high biocompatibility and excellent mechanical characteristics. Even if near-net-shape parts can be produced through AM, semi-finishing and/or finishing machining operations may be necessary to obtain the required surface finish and geometrical tolerances. Micro-milling technique is a soliciting solution for this kind of application due to its high flexibility, elevated material removal rate and direct contact between the tool geometry and work piece. Nevertheless, there are deficiencies in the literature regarding the study of micro-machinability of materials produced by means of AM technologies. In this paper, the micro-machinability of the Ti-6Al-4V alloy obtained by two different AM technologies, namely Electron Beam Melting (EBM) and Direct Metal Laser Sintering (DMLS), was studied and compared in order to assess the influence of the material as-delivered condition. Micro-milling tests were conducted on a high-precision 5-axis Kugler™ micro-milling centre under dry cutting conditions, by using uncoated, two fluted, flat-end-square, tungsten carbide tools with a diameter of 300 microns. The full immersion slotting strategy was chosen under full factorial design of experiments with two factors (cutting speed and feed per tooth). The micro-machinability was evaluated in terms of burr formation, surface integrity (surface topography and surface defects), tool damage and microstructure alterations.
Optimization of Cutting Parameters and Burrs Control with PMMA Coating in Micro-Milling Titanium Alloys
Authors: Li Yu Chao , Liu Zhan Qiang , Cai Yu Kui , Kou Zhao Jun
Published: January 2016

Fabrication of microchannels on titanium alloy with micro-milling is a tough challenge due to the difficultly to remove the burrs formed in machining process. A novel method to gelatinize workpiece surface to control the generation of burr as well as the optimization of cutting parameters are investigated in this paper. Differences existed between the process of micro-milling and that of traditional milling can be accounted for size effect. Influences of feed per tooth, depth of cut and spindle speed on the formation of burr were taken into consideration respectively by single factor method. The topographies of the machined surface with micro-milling were observed and measured by optical microscope. Results showed that the dimensions of burrs increased with the rise of depth of cut. However, it decreased initially, then increased later with the augment of feed per tooth. Sacrifice layer with PMMA was coated and gelatinized on the workpiece surface, which could restrain the plastic deformation of materials during titanium alloy micro-milling. The experimental results presented that the dimensions of burr could reduce greatly by the proposed PMMA coating method compared to materials without coating.
Influence of Cutting Tool Edge Preparation on Cutting Force and Surface Integrity
Authors: Zhao Xue Feng , He Lin , Liu Wei , Zheng Wei Juan
Published: January 2016

The tool edge preparation has a significant influence on the quality of the workpiece surface, the stability of the cutting process and the tool life. In order to investigate the effect of the tool edge preparation, the impact on the cutting force components, the roughness and the residual stress is analyzed through the response surface methodology. The paper presents experimental results of turning tests with different edge radius and changing the cutting speed, the feed amount per tooth, the axial depth, and the radial depth. The research results will put forward theoretical value and practical significance to develop the processing technology of high-speed and efficient cutting, improve the metal cutting theory and prompt the development of the manufacture industry.
Experimental Investigations into Machining of FRP Material
Authors: Zeman Pavel , Kolar Petr , Masek Petr
Published: January 2016

Machining of fibre-reinforced thermosets is becoming a very popular technology today. Nevertheless, machinability of these materials is rather different from conventional materials such as metals since hard and abrasive fibres are combined with relatively soft resin with low glass transition temperature. Special attention has to be given to workpiece quality because delamination and burning of machined surface can occur. An experimental investigation into machinability of a polymeric and cellulose fibre-reinforced resin material was carried out. Milling operations were inspected with respect to process temperature, cutting forces and machined surface quality. The effect of cutting conditions on the mentioned aspects was determined. Standard and tailored cutting tools were used in the investigation. It was observed that surface quality is strongly dependent on tool geometry, milling strategy, fibre orientation and feed. On the other hand, cutting forces are relatively low and dependent on tool geometry and feed. The modified cutting tool with more positive tool geometry showed better results compared to the conventional one.
Effect of Optimizing PID Parameters and Spindle Speeds on Processing Performance of KDP Micro-Defect Mitigation Machine Tool
Authors: Chen Ming Jun , Ma Wen Jing , Xiao Yong
Published: January 2016

PID parameters of machine tool for micro-defect mitigation of KDP crystal had been optimized, after which the velocity fluctuation frequency and amplitude variation of motion axis under different spindle speeds were studied. It is evident that the stability and following errors of the system run better under the velocity&acceleration feed forward PID control algorithm and Notch filters. The velocity fluctuation frequency of motion axis varies with spindle speeds significantly when the tool system is stable, while the fluctuation amplitude variation is slightly changed. To be conclude, the optimal working spindle speed is verified to be 4.78×104 rpm based on comparative experiments, at which damage pits can be mitigated by micro-machining successfully with roughness value of 34.4nm.
Simulation of Meso-Scale Machining of AISI1045 Based on Multiphase Model
Authors: Shang Teng Yi , Xie Li Jing , Chen Xiao Lei , Qin Yu , Fu Tie
Published: January 2016

In the meso-scale machining, feed rate, grain size and tool edge radius are in the same order of magnitude, and cutting process is often carried out in the grain interior and grain boundary. In this paper the meso-cutting process of hot-rolled AISI1045 steel is studied and its metallographic microstructure is analyzed for the establishment of multiphase models which incorporate the effect of ferrite and pearlite grains. In order to discover the applicability of multiphase models to the simulation of meso-cutting, three contrast simulation models including multiphase model with rounded-edge cutting insert (model I), multiphase model with sharp edge cutting insert (model II) and equivalent homogeneous material model with rounded-edge cutting insert (model III) are built up for the meso-orthogonal cutting processes of hot-rolled AISI1045. By comparison with the experiments in terms of chip morphology, cutting force and specific cutting force, the most suitable model is identified. Then the stress distiribution is analyzed. And it is found that multiphase model with tool edge radius can give a more accurate prediction of the global variables and reveal more about these important local variables distribution.
Unbalance Response of HSK Hydraulic Chuck Tooling System for High-Speed Machining
Authors: Tao De Fei , Zheng Deng Sheng , Chen Jian , Wang Gui Cheng
Published: January 2016

High-speed chuck is an important component of high speed machining tooling system. Its properties directly affect the performance and processing quality of advanced numerical control machine. Using the finite element method, the research analyzed influence of inertial centrifugal force caused by unbalance on the dynamic characteristics of HSK hydraulic clamping chuck tooling system and systematically revealed variation of shank, chuck and blade point displacement. It is found that blade point, as well as chuck and shank displacement response amplitude of tooling system rises as a whole with the increase of excitation frequency; the dynamic displacement response increment shows linear growth with unbalance amount, which provides a theoretical basis for optimum design and balancing control of HSK hydraulic chunk tooling system.
Thermal Characteristics Analysis of Hardened Steel Die Transition Region in Machining Process
Authors: Zhang Wei , Liu Hong Li , Wu Tong , Cui Xiao Yan , He Feng Shun
Published: January 2016

Due to the transition region with different hardness, the milling process of assembled hardened steel die is prone to generate flutter, which is hard to ensure surface integrity of workpiece. By establishing the finite element model, the milling process of assembled hardened steel die was calculated by the finite element method. Effects of cutting parameters on milling force and milling temperature were achieved by the above finite element analysis. The laws of the stress and the thermal field distribution in the assembled transition region are analyzed and discovered. The analysis results demonstrate that milling force and milling temperature of the transition region changes in step leaping way. There is a close relationship between processing stability and cutting parameters. The stress and the thermal distribution of the transition region have a significant difference due to the changes in material hardness.
A Unified Cutting Force Model for Flat End Mills Based on Cutter Geometry and Material Properties
Authors: Zhang Xiao Dong , Han Ce , Zhang Ding Hua , Luo Ming
Published: January 2016

A unified oblique cutting force model for flat end mills is developed. In this model, the cutting force is bridged among cutter geometry, material properties and cutting parameters. The cutter angles, material parameters and cutting parameters are the only inputs so that the model is applicable for different cutter-workpiece combinations and cutting parameters. The parameters in the model are solved by the geometric relations, applying Maximum Shear Stress Principle and Stabler’s chip flow rule. The material parameters are identified in a new method with orthogonal milling tests. The simulation results of the proposed model are in good agreement with experiments.
NC Machining Program Simulation and Experiments for Pelton Runner
Authors: Wang Yu , Guo Jia Xin , Wang Bao Tao , Zhai Yuan Sheng
Published: January 2016

With pelton turbines and other complex three-dimensional structure cavities that contains various shaped surfaces and all kinds of larger curvature, the three-axis CNC machine with a tool rotary to achieve the four coordinate overall Pelton CNC machining. According to processing characteristics of pelton runner, the paper determines the selection of materials and the overall structure of the tool. And the appropriate way of milling and milling parameters are made. The overall processing program and processing parameters of pelton runner are designed on this basis. The feasibility of the process and cutting route are verified by the simulation of cutting route and experiments.
Study on the Shear Angles in High Speed Machining of Powder Metallurgy Superalloy
Authors: Qiao Yang , Fu Xiu Li , Pan Yong Zhi
Published: January 2016

High efficiency and high speed are the development directions of modern manufacturing technologies. In the last two decades, high speed machining is successfully applied in cutting steel and alumina alloy, due to its unique advantages. However, it is not yet prevalent in powder metallurgy (PM) superalloy machining. This work focuses on the shear angles and influencing rules in high speed machining PM nickel based superalloy, in order to provide reliable theoretical and practical methods in high efficiency/speed machining this kind of material in production practice.
Research on Overall Aluminum Alloy Flange Machining Deformation
Authors: Qi Xiang Dong , Zhang Wei , Tian Hui , Zheng Xiao Wei , Yu Kai Qin , Yang Yin Fei
Published: January 2016

Machining deformation has been a bottle-neck issue in aeronautical manufacturing field. Due to the large amount of material removal and other issues, machining deformation is predicted more difficultly during the process of 2026-T3511 aluminum alloy rim. Hence a simple full-size model of margin monolithic was built to study the deformation under the influence of residual stress releasing. The process of the structural parts was simulated and the deformation law of overall structure considering residual stress releasing only was revealed. Through the comparative study of different machining processing, control strategy reducing the final part machining deformation and optimum machining allowance range were proposed.
Spectral Properties of Milling and Machined Surface
Authors: Stepan Gabor , Toth Mate , Bachrathy Daniel , Ganeriwala Suri
Published: January 2016

Machine tool vibrations cause uncomfortable noise, may damage the edges of cutting tools or certain parts of machine tools, but most importantly, they always have negative effect on the quality of the machined surface of workpieces. These vibrations are especially intricate in case of milling processes where complex tool geometries are used, like helical, serrated, non-uniform pitch angles, and so on. During the milling process, the arising vibrations include free, forced, self-excited, and even parametrically forced vibrations together with their different combinations. Regarding surface quality, the most harmful is the self-excited one called chatter, which is related to the regenerative effect of the cutting process. Its relation to machined surface quality is demonstrated in an industrial case study. The modelling and the corresponding cutting stability are presented in case of a helical tool applied for milling with large axial immersions. The extremely rich spectrum of the measured vibration signals are analyzed by means of model-based predictions, and the results are compared with the spectral properties of the corresponding machined surfaces. The conclusions open the way for new kinds of chatter identification.
Vibration Monitoring and Analysis of Thin-Walled Casing Milling
Authors: Yao Yi Hang , Wu Bao Hai , Luo Ming
Published: January 2016

Thin-walled elements are widely used in aerospace engines, such as blisk,casing, blade etc. There are significant vibrations while machining because of thesmall thickness and the poor rigidity of thin-walled workpieces which will lead to lowsurface machining quality, low machining efficiency and even worse the huge damageto the workpieces and the tools. Nevertheless, the vibration during milling does nothappen frequently, as it is closely related to the position of the workpiece structureand the machining parameters. The stiffness of the workpiece varies due to thechanging of cutting position. Therefore, vibration only appears in some positionswhen milling thin-walled workpieces. This paper mainly focus on monitoring themachining process in order to analyze the vibration and the position where it occurs.Moreover, with confirming the vibrated position and analyzing the reason of vibration,the paper provides a valid reference to the machining vibration controlling, the qualityand effectiveness of workpiece surface.
Milling Force Analysis and Modeling of Super-Alloy GH2132
Authors: Wu Qing Yu , He Lei , Xiao Hu , Li Liang
Published: January 2016

Iron-based alloy GH2132 is a kind of difficult-to-machine material. In this study, the experiments were processed to research the effect of feed per tooth, axial cutting depth and radial cutting depth on milling force. Variance analysis was made on the three factors. The results reveal that axial cutting depth affects milling force significantly, followed by feed per tooth and radial cutting depth has little influence on it. Two types of empirical model of milling force were established by the result of orthogonal experiment and multiple linear regression analysis. It was verified that both (hm, ap) model and (hm, ap, ae) model had good prediction accuracy compared with the experimental data. By calculating specific cutting force using the (hm, ap) model, a modified coefficient of the specific cutting force for 1mm2 chip cross section was proposed. The study would provide guidance to improve the machining precision and machining efficiency of high temperature alloy materials.
Synergy between Hematopoietic and Radioresistant Stromal Cells Is Required for Autoimmune Manifestations of DNase II−/−IFNaR−/− Mice
Authors: Baum Rebecca , Nündel Kerstin , Pawaria Sudesh , Sharma Shruti , Busto Patricia , Fitzgerald Katherine A. , Gravallese Ellen M. , Marshak-Rothstein Ann
Published: January 2016

Detection of endogenous nucleic acids by cytosolic receptors, dependent on STING, and endosomal sensors, dependent on Unc93b1, can provoke inflammatory responses that contribute to a variety of autoimmune and autoinflammatory diseases. In DNase II–deficient mice, the excessive accrual of undegraded DNA leads to both a STING-dependent inflammatory arthritis and additional Unc93b1-dependent autoimmune manifestations, including splenomegaly, extramedullary hematopoiesis, and autoantibody production. In this study, we use bone marrow chimeras to show that clinical and histological inflammation in the joint depends upon DNase II deficiency in both donor hematopoietic cells and host radioresistant cells. Additional features of autoimmunity in these mice, known to depend on Unc93b1 and therefore endosomal TLRs, also require DNase II deficiency in both donor and host compartments, but only require functional TLRs in the hematopoietic cells. Collectively, our data demonstrate a major role of both stromal and hematopoietic cells in all aspects of DNA-driven autoimmunity. These findings further point to the importance of cytosolic nucleic acid sensors in creating an inflammatory environment that facilitates the development of Unc93b1-dependent autoimmunity.
A REVISION OF THE PACHNEPHORUS FROM THE AFROTROPICAL REGION (COLEOPTERA, CHRYSOMELIDAE)
Authors: Zoia Stefano
Published: January 2016

A revision of the genus Pachnephorus Chevrolat, 1837 from the Afrotropical Region is given and a key to the species is provided. Types of all the previously known taxa have been studied and redescribed; 40 new taxa are described and illustrated: P. achardi n. sp. (Mali), P. aequatorianus n. sp. (Rep. Pop. Congo), P. aethiopicus n. sp. (Etiopia), P. baehri n. sp. (Namibia), P. balyi n. sp. (Angola), P. beharui n. sp. (Etiopia), P. bertiae n. sp. (Madagascar), P. bezdeki n. sp. (Rep. Pop. Congo), P. bracarumvestitus n. sp. (Rep. Pop. Congo), P. bryanti n. sp. (Mali), P. burgeoni n. sp. (Natal), P. camerun­ensis n. sp. (Camerun), P. cristiani n. sp. (Namibia), P. crocodilinus n. sp. (Zambia), P. daccordii n. sp. (Yemen), P. danielssoni n. sp. (Sierra Leone), P. danielssoni congoanus n. ssp. (Rep. Pop. Congo), P. demeyeri n. sp. (Rep. Pop. Congo), P. episternalis n. sp. (Madagascar), P. fabianae n. sp. (Congo), P. fasciatus occidentalis n. ssp. (Nigeria), P. gardinii n. sp. (Etiopia), P. gerstaeckeri n. sp. (Namibia), P. grobbelaarae n. sp. (South Africa), P. hajeki n. sp. (Madagascar), P. lopatini n. sp. (Senegal), P. malicus n. sp. (Mali), P. maroantsetranus n. sp. (Madagascar), P. medvedevi n. sp. (Zambia), P. mo­seykoi n. sp. (Chad), P. pacificus n. sp. (Central Afr. Rep.), P. parentorum n. sp. (Ghana), P. poggii n. sp. (Somalia), P. regalini n. sp. (Zambia), P. rigatoi n. sp. (Kenya), P. sas­sii n. sp. (Guinea Bissau), P. shuteae n. sp. (Rep. South Africa), P. sprecherae n. sp. (Madagascar), P. uhligi n. sp. (Namibia), P. willersi n. sp. (Namibia). The lectoypes of P. conspersus Gerstaecker, 1871, P. senegalensis Achard, 1914, P. latior Pic, 1921 and P. testaceipes Fairmaire, 1880 are designated. A new synonymy (P. costatus Achard, 1914 n. syn. of P. torridus Baly, 1878) and a nomenclatural change (Mecistes lineatus (Pic, 1921) n. comb. for Pachnephorus lineatus Pic, 1921) are proposed; the Lectotypes of M. lineatus and of M. flavipes (Gerstaecker, 1855) are designated.
Updated distribution of Osmoderma eremita in Abruzzo (Italy) and agro-pastoral practices affecting its conservation (Coleoptera: Scarabaeidae)
Authors: Giangregorio Patrizia , Audisio Paolo , Carpaneto Giuseppe Maria , Marcantonio Giuseppe , Maurizi Emanuela , Mosconi Fabio , Campanaro Alessandro
Published: January 2016

New records of Osmoderma eremita (Scopoli, 1763) (Coleoptera: Scarabaeidae: Cetoniinae) are reported for Abruzzo (Italy), together with a review of its distribution in this region. O. eremita is a saproxylic beetle dependent on the presence of hollow deciduous trees with abundant wood mould in their cavities. The major threats for the species are habitat loss and fragmentation. EU Habitats Directive requests to the member States its protection and the monitoring of its conservation status. Detection of its occurrence is the first step to protect the species. The surveys have been carried out in ten sites of Abruzzo by using black cross-windows traps baited with specific pheromone. The species has been recorded for the first time in the Sant’Antonio forest and its presence is confirmed in the Peligna Valley, after a decade. The populations seem to be confined to small patches of suitable habitats. At local level, the abandonment of the pollarding practice (willow and beech forests) and the use of pollarded trees as biomass for fuel are the major threats for this species. Indeed some key actions, such as the protection of old hollow trees and the continuation of pollarding practice in rural landscape, could be key factors for the conservation strategies of the species in the study area.