Search results for: transient condition.

Authors: Yong F. Li, Yi X. Liu, Xiang M. Wang, Feng H. Wang

Abstract:

Wood as a natural renewable material is vulnerable to degradation by microorganisms and susceptible to change in dimension by water. In order to effectively improve the durability of wood, an active reagent, maleic anhydride (Man) was selected for wood modification. Man was first dissolved into a solvent, and then penetrated into wood porous structure under a vacuum/pressure condition. After a final catalyst-thermal treatment, wood modification was finished. The test results indicate that acetone is a good solvent for transporting Man into wood matrix. SEM observation proved that wood samples treated by Man kept a good cellular structure, indicating a well penetration of Man into wood cell walls. FTIR analysis suggested that Man reacted with hydroxyl groups on wood cell walls by its ring-ether group, resulting in reduction of amount of hydroxyl groups and resultant good dimensional stability as well as fine decay resistance. Consequently, Man modifying wood to improve its durability is an effective method.

Keywords: Wood, porous structure, durability improvement, maleic anhydride

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Authors: B. Tondu, N. Bardou

Abstract:

The recent development of humanoid robots has led robot designers to imagine a great variety of anthropomorphic forms for human-like machine. Which form is the best ? We try to answer this question from a double meaning of the anthropomorphism : a positive anthropomorphism corresponing to the realization of an effective anthropomorphic form object and a negative one corresponding to our natural tendency in certain circumstances to give human attributes to non-human beings. We postulate that any humanoid robot is concerned by both these two anthropomorphism kinds. We propose to use gestalt theory and Heider-s balance theory in order to analyze how negative anthropomorphism can influence our perception of human-like robots. From our theoretical approach we conclude that an “even shape" as defined by gestalt theory is not a sufficient condition for a good integration of future humanoid robots into a human community. Aesthetic perception of the robot cannot be splitted from a social perception : a humanoid robot, any how the efforts made for improving its appearance, could be rejected if it is devoted to a task with too high affective implications.

Keywords: Robot appearance, humanoid robot, uncanny valley, human-robot-interaction.

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Authors: Y. Parvizi, M. Gorji, M.H. Mahdian, M. Omid

Abstract:

Soil organic carbon (SOC) plays a key role in soil fertility, hydrology, contaminants control and acts as a sink or source of terrestrial carbon content that can affect the concentration of atmospheric CO2. SOC supports the sustainability and quality of ecosystems, especially in semi-arid region. This study was conducted to determine relative importance of 13 different exploratory climatic, soil and geometric factors on the SOC contents in one of the semiarid watershed zones in Iran. Two methods canonical discriminate analysis (CDA) and feed-forward back propagation neural networks were used to predict SOC. Stepwise regression and sensitivity analysis were performed to identify relative importance of exploratory variables. Results from sensitivity analysis showed that 7-2-1 neural networks and 5 inputs in CDA models output have highest predictive ability that explains %70 and %65 of SOC variability. Since neural network models outperformed CDA model, it should be preferred for estimating SOC.

Keywords: Soil organic carbon, modeling, neural networks, CDA.

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Authors: Jaroslav Polec, Lenka Krulikovská, Natália Helešová, Tomáš Hirner

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In this paper we present a novel approach for face image coding. The proposed method makes a use of the features of video encoders like motion prediction. At first encoder selects appropriate prototype from the database and warps it according to features of encoding face. Warped prototype is placed as first I frame. Encoding face is placed as second frame as P frame type. Information about features positions, color change, selected prototype and data flow of P frame will be sent to decoder. The condition is both encoder and decoder own the same database of prototypes. We have run experiment with H.264 video encoder and obtained results were compared to results achieved by JPEG and JPEG2000. Obtained results show that our approach is able to achieve 3 times lower bitrate and two times higher PSNR in comparison with JPEG. According to comparison with JPEG2000 the bitrate was very similar, but subjective quality achieved by proposed method is better.

Keywords: Triangulation, H.264, Model-based coding, Average face

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Authors: Shabrina Pritta Radyanti, Harimukti Wandebori

Abstract:

A research study was conducted with an objective to propose a collaborative business strategy of a oil and gas trading company, representing PPT Energy Trading Co., Ltd., with its shareholder, especially electricity and power supply companies for LNG Form of Coal Bed Methane in B2B Transaction. Collaborative business strategy is a strategy to collaborate with other organizations due to have future benefits in both parties, or achieve the business objective through the collaboration of business, its strategy and partners. A structured interview was established to collect the required primary data from the company. Not only interview, but also company’s business plan and annual report were collected and analyzed for the company’s current condition. As the result, this research shows a recommendation to propose a new collaborative strategy with limiting its target market, diversifying product, conducting new business model, and considering other stakeholders.

Keywords: collaborative business strategy, trading company, LNG, coal bed methane

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Authors: Ranjit Chatterjee, P. K. Paul

Abstract:

The influence of organic amendments and inorganic fertilizers on cabbage head was investigated to determine their effect on storage behavior and organoleptic quality. Field cabbage was raised by combining fourteen different treatments comprising of organic amendments and inorganic fertilizers at different levels. The result showed that nutrient schedule of the crop significantly influenced the physiological loss in weight (PLW) and organoleptic quality of cabbage head and judicious selection of nutrient combination can extend the storage life and reduce the post harvest detoriaration of head. The nutrient schedule comprising of higher level of FYM (16 t ha^-1) along with 75% of recommended inorganic fertilizers in conjugation with seedling inoculation of biofertilizer emerged as potential nutrient source for improving storage life, marketability and maintaining nutritional and organoleptic quality under ambient storage condition.

Keywords: Cabbage head, Organic amendments, Organoleptic quality, Physiological loss in weight (PLW).

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Authors: Suthat Turapan, Cattareya Yotkamchornkun, Kamchai Nuithitikul

Abstract:

The production of biodiesel from crude palm oil with a homogeneous base catalyst is unlikely owing to considerable formation of soap. Free fatty acids (FFA) in crude palm oil need to be reduced, e.g. by esterification. This study investigated the activity of sulfated zirconia calcined at various temperatures for esterification of FFA in crude palm oil to biodiesel. It was found that under a proper reaction condition, sulfated zirconia well catalyzes esterification. FFA content can be reduced to an acceptable value for typical biodiesel production with a homogeneous base catalyst. Crystallinity and sulfate attachment of sulfated zirconia depend on calcination temperature during the catalyst preparation. Too low temperature of calcination gives amorphous sulfated zirconia which has low activity for esterification of FFA. In contrast, very high temperature of calcination removes sulfate group, consequently, conversion of FFA is reduced. The appropriate temperature range of calcination is 550-650 oC.

Keywords: Biodiesel, Esterification, Free fatty acids, Sulfatedzirconia.

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Authors: Chun Hsiang Yang, Cheng Chia Lee, Chiun Hsun Chen

Abstract:

In this study, the effects of biogas fuels on the performance of an annular micro gas turbine (MGT) were assessed experimentally and numerically. In the experiments, the proposed MGT system was operated successfully under each test condition; minimum composition to the fuel with the biogas was roughly 50% CH4 with 50% CO2. The power output was around 170W at 85,000 RPM as 90% CH4 with 10% CO2 was used and 70W at 65,000 RPM as 70% CH4 with 30% CO2 was used. When a critical limit of 60% CH4 was reached, the power output was extremely low. Furthermore, the theoretical Brayton cycle efficiency and electric efficiency of the MGT were calculated as 23% and 10%, respectively. Following the experiments, the measured data helped us identify the parameters of dynamic model in numerical simulation. Additionally, a numerical analysis of re-designed combustion chamber showed that the performance of MGT could be improved by raising the temperature at turbine inlet. This study presents a novel distributed power supply system that can utilize renewable biogas. The completed micro biogas power supply system is small, low cost, easy to maintain and suited to household use.

Keywords: Micro Gas Turbine, Biogas; System Identification, Distributed power supply system

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Authors: Venny, S. Gan, H. K. Ng

Abstract:

The performance of modified Fenton (MF) treatment to promote PAH oxidation in artificially contaminated soil was investigated in packed soil column with a hydrogen peroxide (H2O2) delivery system simulating in situ injection. Soil samples were spiked with phenanthrene (low molecular weight PAH) and fluoranthene (high molecular weight PAH) to an initial concentration of 500 mg/kg dried soil each. The effectiveness of process parameters H2O2/soil, iron/soil, chelating agent/soil weight ratios and reaction time were studied using a 24 three level factorial design experiments. Statistically significant quadratic models were developed using Response Surface Methodology (RSM) for degrading PAHs from the soil samples. Optimum operating condition was achieved at mild range of H2O2/soil, iron/soil and chelating agent/soil weight ratios, indicating cost efficient method for treating highly contaminated lands.

Keywords: Fenton, polycyclic aromatic hydrocarbon, chelate, response surface methodology

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Authors: Ho Jae Lee, Do Gyeum Kim, Jang Hwa Lee, Myoung Suk Cho

Abstract:

A concrete structure is designed and constructed for its purpose of use, and is expected to maintain its function for the target durable years from when it was planned. Nevertheless, as time elapses the structure gradually deteriorates and then eventually degrades to the point where the structure cannot exert the function for which it was planned. The performance of concrete that is able to maintain the level of the performance required over the designed period of use as it has less deterioration caused by the elapse of time under the designed condition is referred to as Durability. There are a number of causes of durability degradation, but especially chloride damage, carbonation, freeze-thaw, etc are the main causes. In this study, carbonation, one of the main causes of deterioration of the durability of a concrete structure, was investigated via a microstructure analysis technique. The method for the measurement of carbonation was studied using the existing indicator method, and the method of measuring the progress of carbonation in a quantitative manner was simultaneously studied using a FT-IR (Fourier-Transform Infrared) Spectrometer along with the microstructure analysis technique.

Keywords: Concrete, Carbonation, Microsturcture, FT-IR

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Authors: F. Zaefarian, M. Bagheri, B. Bicharanlou, G.A. Asadi, V. Akbarpour

Abstract:

Intercropping is one of the sustainable agricultural factors. The SPAD meter can be used to predict nitrogen index reliably, it may also be a useful tool for assessing the relative impact of weeds on crops. In order to study the effect of weeds on SPAD in corn (Zea mays L.), sweet basil (Ocimum basilicum L.) and borage (Borago officinalis L.) in intercropping system, a factorial experiment was conducted in three replications in 2011. Experimental factors were included intercropping of corn with sweet basil and borage in different ratios (100:0, 75:25, 50:50, 25:75 and 0:100 corn: borage or sweet basil) and weed infestation (weed control and weed interference). The results showed that intercropping of corn with sweet basil and borage increased the SPAD value of corn compare to monoculture in weed interference condition. Sweet basil SPAD value in weed control treatments (43.66) was more than weed interference treatments (40.17). Corn could increase the borage SPAD value compare to monoculture in weed interference treatments.

Keywords: Borage, Sweet basil, SPAD, Weed Infestation

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Authors: Liu Xuedong, Liu Hanpeng, Zhou Ling

Abstract:

Study fluid flow and heat transfer characteristics of microchannel in a primary Cross-corrugated(CC) surface recuperators with corrugations and without corrugations, using CFD method. The pitch-over-height ratios P/H of Cross-corrugated (CC) surface is from 1.5 to 4.0, included angles β=75º. The study was performed using CFD software FLUENT to create unit model and simulate fluid temperature, velocity, heat transfer coefficient and other parameters. The results from these simulations were compared to experimental data. It is concluded that, when the Reynolds number is constant, if increase P/H, j/f will decrease, also the decreasing trend will become weak. Under the condition of P/H=2.2, if increase the inlet velocity j/f will decrease; in addition, the heat transfer performance in surface with corrugation will increase 10% compared to that without corrugation. The study results can provide the basis to optimize the design, select the type of heat transfer surface, the scale structure, and heat-transfer surface arrangement for recuperators.

Keywords: Cross-corrugated surface, Primary surface, Numerical simulation, Heat transfer.

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Authors: Maria Luskova, Maria Hudakova, Katarina Buganova

Abstract:

Established objective and subjective preconditions for entrepreneurship, forming the business organically related whole, are the necessary condition of successful entrepreneurial activities. Objective preconditions for entrepreneurship are developed by market economy that should stimulate entrepreneurship by allowing the use of economic opportunities for all those who want to do business in respective field while providing guarantees to all owners and creating a stable business environment for entrepreneurs. Subjective preconditions of entrepreneurship are formed primarily by personal characteristics of the entrepreneur. These are his properties, abilities, skills, physiological and psychological preconditions which may be inherited, inborn or sequentially developed and obtained during his life on the basis of education and influences of surrounding environment. The paper is dealing with issues of objective and subjective preconditions for entrepreneurship and provides their analysis in view of the current situation in Slovakia. It presents risks of the business environment in Slovakia that the Slovak managers considered the most significant in 2014 and defines the dominant attributes of the entrepreneur in the current business environment in Slovakia.

Keywords: Entrepreneurship, innovations, opportunity, risk, uncertainty.

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Authors: Zefry Darmawan, Shigeyuki Haruyama, Ken Kaminishi

Abstract:

Product development is a big issue in the industrial competition and takes a serious part in development of technology. Product development process could adapt high changes of market needs and transform into engineering concept in order to produce high-quality product. One of the latest methods in product development is Analysis-Led-Design (ALD). It utilizes digital engineering design tools with finite analysis to perform product robust analysis and valuable for product reliability assurance. Heavy machinery which operates under severe condition should maintain safety to the customer when faced with potential hazard. Cab frame should able to absorb the energy while collision. Through ALD, a series of improvement of cab frame to increase energy absorption was made and analyzed. Improvement was made by modifying shapes of frame and-or install absorption device in certain areas. Simulation result showed that install absorption device could increase absorption energy than modifying shape.

Keywords: ALD, ROPS, energy absorption, cab frame.

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Authors: Davide Pierattoni, Ivan Macor, Pier Luca Montessoro

Abstract:

In the recent years multimedia traffic and in particular VoIP services are growing dramatically. We present a new algorithm to control the resource utilization and to optimize the voice codec selection during SIP call setup on behalf of the traffic condition estimated on the network path. The most suitable methodologies and the tools that perform realtime evaluation of the available bandwidth on a network path have been integrated with our proposed algorithm: this selects the best codec for a VoIP call in function of the instantaneous available bandwidth on the path. The algorithm does not require any explicit feedback from the network, and this makes it easily deployable over the Internet. We have also performed intensive tests on real network scenarios with a software prototype, verifying the algorithm efficiency with different network topologies and traffic patterns between two SIP PBXs. The promising results obtained during the experimental validation of the algorithm are now the basis for the extension towards a larger set of multimedia services and the integration of our methodology with existing PBX appliances.

Keywords: Integrated voice-data communication, computernetwork performance, resource optimization.

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Authors: Kevser Dincer, Basma Waisi, M. Ozan Ozdemir, Ugur Pasaogullari, Jeffrey McCutcheon

Abstract:

Nanofibers are defined as fibers with diameters less than 100 nanometers. In this study, behaviours of activated carbon nanofiber (ACNF), carbon nanofiber (CNF), polyacrylonitrile/ carbon nanotube (PAN/CNT), polyvinyl alcohol/nanosilver (PVA/Ag) in proton exchange membrane (PEM) fuel cells are investigated experimentally. This material was used as gas diffusion layer (GDL) in PEM fuel cells. In this study, the electrical conductivities of nanofiber and nanofiber/nanoparticles have been studied to understand their effects on PEM fuel cell performance. According to the experimental results, the maximum electrical conductivity performance of the fuel cell with nanofiber was found to be at PVA/Ag (at UConn condition). The electrical conductivities of CNF, ACNF, PAN/CNT are lower for PEM. The resistance of cell with PVA/Ag is lower than the resistance of cell with PAN/CNT, ACNF, CNF.

Keywords: Proton exchange membrane fuel cells, electrospinning, carbon nanofiber, activate carbon nanofiber, PVA fiber, pan fiber, carbon nanotube, nanoparticle, nanocomposites.

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Authors: Adel A. Ghoneim

Abstract:

In most existing buildings in hot climate, cooling loads lead to high primary energy consumption and consequently high CO2 emissions. These can be substantially decreased with integrated renewable energy systems. Kuwait is characterized by its dry hot long summer and short warm winter. Kuwait receives annual total radiation more than 5280 MJ/m2 with approximately 3347 h of sunshine. Solar energy systems consist of PV modules and parabolic trough collectors are considered to satisfy electricity consumption, domestic water heating, and cooling loads of an existing building. This paper presents the results of an extensive program of energy conservation and energy generation using integrated photovoltaic (PV) modules and Parabolic Trough Collectors (PTC). The program conducted on an existing institutional building intending to convert it into a Net-Zero Energy Building (NZEB) or near net Zero Energy Building (nNZEB). The program consists of two phases; the first phase is concerned with energy auditing and energy conservation measures at minimum cost and the second phase considers the installation of photovoltaic modules and parabolic trough collectors. The 2-storey building under consideration is the Applied Sciences Department at the College of Technological Studies, Kuwait. Single effect lithium bromide water absorption chillers are implemented to provide air conditioning load to the building. A numerical model is developed to evaluate the performance of parabolic trough collectors in Kuwait climate. Transient simulation program (TRNSYS) is adapted to simulate the performance of different solar system components. In addition, a numerical model is developed to assess the environmental impacts of building integrated renewable energy systems. Results indicate that efficient energy conservation can play an important role in converting the existing buildings into NZEBs as it saves a significant portion of annual energy consumption of the building. The first phase results in an energy conservation of about 28% of the building consumption. In the second phase, the integrated PV completely covers the lighting and equipment loads of the building. On the other hand, parabolic trough collectors of optimum area of 765 m2 can satisfy a significant portion of the cooling load, i.e about73% of the total building cooling load. The annual avoided CO2 emission is evaluated at the optimum conditions to assess the environmental impacts of renewable energy systems. The total annual avoided CO2 emission is about 680 metric ton/year which confirms the environmental impacts of these systems in Kuwait.

Keywords: Building integrated renewable systems, Net-Zero Energy Building, solar fraction, avoided CO2 emission.

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Authors: Antaryami Mishra

Abstract:

Composite pins of rubber dust collected from tyre retreading centres of trucks, cars and buses etc.and epoxy with weight percentages of 10. 15, and 20 % of rubber (weight fractions of 9, 13 and 17 % respectively) have been prepared in house with the help of a split wooden mould. The pins were tested in a pin-on-disc wear monitor to determine the co-efficient of friction and weight losses with varying speeds, loads and time. The wear volume and wear rates have also been found out for all these three specimens.. It is observed that all the specimens have exhibited very low coefficient of friction and low wear rates under dry sliding condition. Out of the above three samples tested, the specimen with 10 % rubber dust by weight has shown lowest wear rates. However a peculiar result i.e decreasing trend has been obtained with 20% reinforcement of rubber in epoxy while rubbed against steel at varying speeds. This might have occurred due to high surface finish of the disc and formation of a thin transfer layer from the composite

Keywords: epoxy, rubber dust, composites, weight fractions, pin-on-disc wear tests, wear volume and wear rate calculations.

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Authors: Ramdan B. A. Koad, Ahmed. F. Zobaa

Abstract:

Since the output characteristics of photovoltaic (PV) system depends on the ambient temperature, solar radiation and load impedance, its maximum power point (MPP) is not constant. Under each condition PV module has a point at which it can produce its MPP. Therefore, a maximum power point tracking (MPPT) method is needed to uphold the PV panel operating at its MPP. This paper presents comparative study between the conventional MPPT methods used in (PV) system: Perturb and Observe (P&O), Incremental Conductance (IncCond), andParticle Swarm Optimization (PSO) algorithmfor (MPPT) of (PV) system. To evaluate the study, the proposed PSO MPPT is implemented on a DC-DC cuk converter and has been compared with P&O and INcond methods in terms of their tracking speed, accuracy and performance by using the Matlab tool Simulink. The simulation result shows that the proposed algorithm is simple, and is superior to the P&O and IncCond methods.

Keywords: Incremental Conductance (IncCond) Method, Perturb and Observe (P&O) Method, Photovoltaic Systems (PV) and Practical Swarm Optimization Algorithm (PSO).

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Authors: K. Daud, A. F. Abidin, N. Hamzah, H. S. Nagindar Singh

Abstract:

This paper produces a new approach for power quality analysis using a windowing technique based on Continuous S-transform (CST). This half-cycle window technique approach can detect almost correctly for initial detection of disturbances i.e. voltage sags, swells, and transients. Samples in half cycle window has been analyzed based continuous S-transform for entire disturbance waveform. The modified parameter has been produced by MATLAB programming m-file based on continuous s-transform. CST has better time frequency and localization property than traditional and also has ability to detect the disturbance under noisy condition correctly. The excellent time-frequency resolution characteristic of the CST makes it the most an attractive candidate for analysis of power system disturbances signals.

Keywords: Power quality disturbances, initial detection, half cycle windowing, continuous S-transform.

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Authors: Mongkorn Klingajay, Tawatchai Jitson

Abstract:

The pipe inspection operation is the difficult detective performance. Almost applications are mainly relies on a manual recognition of defective areas that have carried out detection by an engineer. Therefore, an automation process task becomes a necessary in order to avoid the cost incurred in such a manual process. An automated monitoring method to obtain a complete picture of the sewer condition is proposed in this work. The focus of the research is the automated identification and classification of discontinuities in the internal surface of the pipe. The methodology consists of several processing stages including image segmentation into the potential defect regions and geometrical characteristic features. Automatic recognition and classification of pipe defects are carried out by means of using an artificial neural network technique (ANN) based on Radial Basic Function (RBF). Experiments in a realistic environment have been conducted and results are presented.

Keywords: Artificial neural network, Radial basic function, Curve fitting, CCTV, Image segmentation, Data acquisition.

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Authors: G. Santamato, M. Solazzi, A. Frisoli

Abstract:

Systems for detection of damages in railway pantographs effectively reduce the cost of maintenance and improve time scheduling. In this paper, we present an approach to design a monitoring tool fitting strong customer requirements such as portability and ease of use. Pantograph has been modeled to estimate its dynamical properties, since no data are available. With the aim to focus on suspensions health, a two Degrees of Freedom (DOF) scheme has been adopted. Parameters have been calculated by means of analytical dynamics. A Finite Element Method (FEM) modal analysis verified the former model with an acceptable error. The detection strategy seeks phase-plots topology alteration, induced by defects. In order to test the suitability of the method, leakage in the dashpot was simulated on the lumped model. Results are interesting because changes in phase plots are more appreciable than frequency-shift. Further calculations as well as experimental tests will support future developments of this smart strategy.

Keywords: Pantograph models, phase-plots, structural health monitoring, vibration-based condition monitoring.

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Authors: Katleho D. Makatjane, Kalebe M. Kalebe

Abstract:

The present paper used time-varying parameters which are based on the score function of a probability density at time t to model volatility of saving rate. We used a scaled likelihood function to update the parameters of the model overtime. Our results revealed high diligence of time-varying since the location parameter is greater than zero. Furthermore, we discovered a leptokurtic condition on saving rate’s distribution. Kapetanios, Shin-Shell Nonlinear Augmented Dickey-Fuller (KSS-NADF) test showed that the saving rate has a nonlinear unit root; therefore, it can be modeled by a generalised autoregressive score (GAS) model. Additionally, value at risk (VaR) and conditional tail expectation (CTE) indicate that 99% of the time people in Lesotho are saving more than spending. This puts the economy in high risk of not expanding. Therefore, the monetary policy committee (MPC) of Lesotho should revise their monetary policies towards this high saving rates risk.

Keywords: Generalized autoregressive score, time-varying, saving rate, Lesotho.

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Authors: Nurzaki Ikhsan, Ahmad Saifizul Abdullah, Rahizar Ramli

Abstract:

One of the functions of the commercial heavy vehicle is to safely and efficiently transport goods and people. Due to its size and carrying capacity, it is important to study the vehicle dynamic stability during cornering. Study has shown that there are a number of overloaded heavy vehicles or permissible Gross Vehicle Weight (GVW) violations recorded at selected areas in Malaysia assigned by its type and category. Thus, the objective of this study is to investigate the correlation and effect of the GVW on heavy vehicle stability during cornering event using simulation. Various selected heavy vehicle types and category are simulated using IPG/Truck Maker® with different GVW and road condition (coefficient of friction of road surface), while the speed, driver characteristic, center of gravity of load and road geometry are constant. Based on the analysis, the relationship between GVW and lateral acceleration were established. As expected, on the same value of coefficient of friction, the maximum lateral acceleration would be increased as the GVW increases.

Keywords: Heavy Vehicle, Road Safety, Vehicle Stability, Lateral Acceleration, Gross Vehicle Weight.

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Authors: J. Menčík

Abstract:

Actual load, material characteristics and other quantities often differ from the design values. This can cause worse function, shorter life or failure of a civil engineering structure, a machine, vehicle or another appliance. The paper shows main causes of the uncertainties and deviations and presents a systematic approach and efficient tools for their elimination or mitigation of consequences. Emphasis is put on the design stage, which is most important for reliability ensuring. Principles of robust design and important tools are explained, including FMEA, sensitivity analysis and probabilistic simulation methods. The lifetime prediction of long-life objects can be improved by long-term monitoring of the load response and damage accumulation in operation. The condition evaluation of engineering structures, such as bridges, is often based on visual inspection and verbal description. Here, methods based on fuzzy logic can reduce the subjective influences.

Keywords: Design, fuzzy methods, Monte Carlo, reliability, robust design, sensitivity analysis, simulation, uncertainties.

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Authors: Zhongzhen Luo, Saeid Habibi, Martin v. Mohrenschildt

Abstract:

Self-driving vehicle require a high level of situational awareness in order to maneuver safely when driving in real world condition. This paper presents a LiDAR based real time perception system that is able to process sensor raw data for multiple target detection and tracking in dynamic environment. The proposed algorithm is nonparametric and deterministic that is no assumptions and priori knowledge are needed from the input data and no initializations are required. Additionally, the proposed method is working on the three-dimensional data directly generated by LiDAR while not scarifying the rich information contained in the domain of 3D. Moreover, a fast and efficient for real time clustering algorithm is applied based on a radially bounded nearest neighbor (RBNN). Hungarian algorithm procedure and adaptive Kalman filtering are used for data association and tracking algorithm. The proposed algorithm is able to run in real time with average run time of 70ms per frame.

Keywords: LiDAR, real-time system, clustering, tracking, data association.

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Authors: Krishna Mohana Rao, G. Ravi Kumar, P. Sowmya

Abstract:

This paper presents a study of the Taguchi design application to optimize surface quality in damper inserted end milling operation. Maintaining good surface quality usually involves additional manufacturing cost or loss of productivity. The Taguchi design is an efficient and effective experimental method in which a response variable can be optimized, given various factors, using fewer resources than a factorial design. This Study included spindle speed, feed rate, and depth of cut as control factors, usage of different tools in the same specification, which introduced tool condition and dimensional variability. An orthogonal array of L9(3^4)was used; ANOVA analyses were carried out to identify the significant factors affecting surface roughness, and the optimal cutting combination was determined by seeking the best surface roughness (response) and signal-to-noise ratio. Finally, confirmation tests verified that the Taguchi design was successful in optimizing milling parameters for surface roughness.

Keywords: ANOVA, Damper, End Milling, Optimization, Surface roughness, Taguchi design.

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Authors: Nabnit Panigrahi, M. K. Mohanty, S. K. Acharya, S. R Mishra, R. C. Mohanty

Abstract:

This paper presents experimental investigation carried out on an unmodified four stroke diesel engine running with preheated straight vegetable oil (SVO) of Karanja. The viscosity of straight karanja oil was reduced by preheating the oil up to 1600C under different load condition. The preheating was done with the help of a Shell and Tube heat exchanger equipment without using any external power source. The heat exchanger was designed in the lab and the heating source was by waste exhaust gas from engine. The experimental results data were analyzed by using 20% blends of svo of Karanja with 80% diesel by volume and 100% preheated svo of karanja for various parameters like specific fuel consumption, brake thermal efficiency and emission of exhaust gas like CO, CO₂, HC and NOx. The results indicated that by using straight karanja oil, the emission parameter increases as compared to diesel but regarding engine performance it was found to be very close to that of diesel. All total it can be a replacement of diesel with a small efficiency drop.

Keywords: Karanja oil, Performance analysis, Shell &Tube heat exchanger, SVO.

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Authors: Masatora Daito, Hisashi Kojima

Abstract:

In this research, the authors analyze network stability using agent-based simulation. Firstly, the authors focus on analyzing large networks (eight agents) by connecting different two stable small social networks (A small stable network is consisted on four agents.). Secondly, the authors analyze the network (eight agents) shape which is added one agent to a stable network (seven agents). Thirdly, the authors analyze interpersonal comparison of utility. The “star-network "was not found on the result of interaction among stable two small networks. On the other hand, “decentralized network" was formed from several combination. In case of added one agent to a stable network (seven agents), if the value of “c"(maintenance cost of per a link) was larger, the number of patterns of stable network was also larger. In this case, the authors identified the characteristics of a large stable network. The authors discovered the cases of decreasing personal utility under condition increasing total utility.

Keywords: Social Network, Symmetric Situation, Network Stability, Agent-Based Modeling.

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Authors: Mohammadreza Nezamirad, Nasim Sabetpour, Azadeh Yazdi, Amirmasoud Hamedi

Abstract:

In this study OpenFOAM 4.4.2 was used to investigate flow inside the coronary artery of the heart. This step is the first step of our future project, which is to include conjugate heat transfer of the heart with three main coronary arteries. Three different velocities were used as inlet boundary conditions to see the effect of velocity increase on velocity, pressure, and wall shear of the coronary artery. Also, three different fluids, namely the University of Wisconsin solution, gelatin, and blood was used to investigate the effect of different fluids on flow inside the coronary artery. A code based on Reynolds Stress Navier Stokes (RANS) equations was written and implemented with the real boundary condition that was calculated based on MRI images. In order to improve the accuracy of the current numerical scheme, hex dominant mesh is utilized. When the inlet velocity increases to 0.5 m/s, velocity, wall shear stress, and pressure increase at the narrower parts.

Keywords: CFD, heart, simulation, OpenFOAM.

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