Search results for: Energy balance equation
Commenced in January 2007
Frequency: Monthly
Edition: International
Paper Count: 4148

Search results for: Energy balance equation

2078 Residence Time Distribution in a Two Impinging Streams Cyclone Reactor: CFD Prediction and Experimental Validation

Authors: Nahid Ghasemi, Morteza Sohrabi, Yasan Soleymani

Abstract:

The quantified residence time distribution (RTD) provides a numerical characterization of mixing in a reactor, thus allowing the process engineer to better understand mixing performance of the reactor.This paper discusses computational studies to investigate flow patterns in a two impinging streams cyclone reactor(TISCR) . Flow in the reactor was modeled with computational fluid dynamics (CFD). Utilizing the Eulerian- Lagrangian approach, implemented in FLUENT (V6.3.22), particle trajectories were obtained by solving the particle force balance equations. From simulation results obtained at different Δts, the mean residence time (tm) and the mean square deviation (σ2) were calculated. a good agreement can be observed between predicted and experimental data. Simulation results indicate that the behavior of complex reactor systems can be predicted using the CFD technique with minimum data requirement for validation.

Keywords: Impinging streams reactor, Residence timedistribution, CFD, Eulerian-Lagrangian approach

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2077 Research on the Problems of Housing Prices in Qingdao from a Macro Perspective

Authors: Liu Zhiyuan, Sun Zongdi, Liu Zhiyuan, Sun Zongdi

Abstract:

Qingdao is a seaside city. Taking into account the characteristics of Qingdao, this article established a multiple linear regression model to analyze the impact of macroeconomic factors on housing prices. We used stepwise regression method to make multiple linear regression analysis, and made statistical analysis of F test values and T test values. According to the analysis results, the model is continuously optimized. Finally, this article obtained the multiple linear regression equation and the influencing factors, and the reliability of the model was verified by F test and T test.

Keywords: Housing prices, multiple linear regression model, macroeconomic factors, Qingdao City.

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2076 Thermo-Elastic Properties of Artificial Limestone Bricks with Wood Sawdust

Authors: Paki Turgut, Mehmet Gumuscu

Abstract:

In this study, artificial limestone brick samples are produced by using wood sawdust wastes (WSW) having different grades of sizes and limestone powder waste (LPW). The thermo-elastic properties of produced brick samples in various WSW amounts are investigated. At 30% WSW replacement with LPW in the brick sample the thermal conductivity value is effectively reduced and the reduction in the thermal conductivity value of brick sample at 30% WSW replacement with LPW is about 38.9% as compared with control sample. The energy conservation in buildings by using LPW and WSW in masonry brick material production having low thermal conductivity reduces energy requirements. A strong relationship is also found among the thermal conductivity, unit weight and ultrasonic pulse velocity values of brick samples produced. It shows a potential to be used for walls, wooden board substitute, alternative to the concrete blocks, ceiling panels, sound barrier panels, absorption materials etc.

Keywords: Limestone dust, masonry brick, thermo-elastic properties, wood sawdust.

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2075 Fuzzy Control of Thermally Isolated Greenhouse Building by Utilizing Underground Heat Exchanger and Outside Weather Conditions

Authors: Raghad Alhusari, Farag Omar, Moustafa Fadel

Abstract:

A traditional greenhouse is a metal frame agricultural building used for cultivation plants in a controlled environment isolated from external climatic changes. Using greenhouses in agriculture is an efficient way to reduce the water consumption, where agriculture field is considered the biggest water consumer world widely. Controlling greenhouse environment yields better productivity of plants but demands an increase of electric power. Although various control approaches have been used towards greenhouse automation, most of them are applied to traditional greenhouses with ventilation fans and/or evaporation cooling system. Such approaches are still demanding high energy and water consumption. The aim of this research is to develop a fuzzy control system that minimizes water and energy consumption by utilizing outside weather conditions and underground heat exchanger to maintain the optimum climate of the greenhouse. The proposed control system is implemented on an experimental model of thermally isolated greenhouse structure with dimensions of 6x5x2.8 meters. It uses fans for extracting heat from the ground heat exchanger system, motors for automatic open/close of the greenhouse windows and LED as lighting system. The controller is integrated also with environmental condition sensors. It was found that using the air-to-air horizontal ground heat exchanger with 90 mm diameter and 2 mm thickness placed 2.5 m below the ground surface results in decreasing the greenhouse temperature of 3.28 ˚C which saves around 3 kW of consumed energy. It also eliminated the water consumption needed in evaporation cooling systems which are traditionally used for cooling the greenhouse environment.

Keywords: Automation, earth-to-air heat exchangers, fuzzy control, greenhouse, sustainable buildings.

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2074 How Herding Bias Could be Derived from Individual Investor Types and Risk Tolerance?

Authors: Huei-Wen Lin

Abstract:

This paper is to clarify the relationship of individual investor types, risk tolerance and herding bias. The questionnaire survey investigation is conducted to collect 389 valid and voluntary individual investors and to examine how the risk tolerance plays as a mediator between four types of personality and herding bias. Based on featuring BB&K model and reviewing the prior literature of psychology, a linear structural model are constructed and further used to evaluate the path of herding formation through the analysis of Structural Equation Modeling (SEM). The results showed that more impetuous investors would be prone to herding bias directly, but rather exhibit higher risk tolerance. However, risk tolerance would fully mediate between the level of confidence (i.e., confident or anxious) and herding bias, but not mediate between the method of action (careful or impetuous) for individual investors.

Keywords: Herding, investor types, risk tolerance.

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2073 Assessment of Menus in a Selected Social Welfare Home with Regard to Nutritional Recommendations

Authors: E. Grochowska-Niedworok, K. Brukalo, B. Całyniuk, J. Piekorz, M. Kardas

Abstract:

The aim of the study was to assess diets of residents of nursing homes. Provided by social welfare home, 10 day menus were introduced into the computer program Diet 5 and analyzed in respect of protein, fats, carbohydrates, energy, vitamin D and calcium. The resulting mean values of 10-day menus were compared with the existing Nutrition Standards for Polish population. The analysis menus showed that the average amount of energy supplied from food is not sufficient. Carbohydrates in food supply are too high and represent 257% of normal. The average value of fats and proteins supplied with food is adequate 85.2 g/day and 75.2 g/day. The calcium content of the diet is 513.9 mg/day. The amount of vitamin D supplied in the age group 51-65 years is 2.3 µg/day. Dietary errors that have been shown are due to the lack of detailed nutritional guidelines for nursing homes, as well as state-owned care facilities in general.

Keywords: Assessment of diet, essential nutrients, social welfare home, nutrition.

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2072 Extended Arithmetic Precision in Meshfree Calculations

Authors: Edward J. Kansa, Pavel Holoborodko

Abstract:

Continuously differentiable radial basis functions (RBFs) are meshfree, converge faster as the dimensionality increases, and is theoretically spectrally convergent. When implemented on current single and double precision computers, such RBFs can suffer from ill-conditioning because the systems of equations needed to be solved to find the expansion coefficients are full. However, the Advanpix extended precision software package allows computer mathematics to resemble asymptotically ideal Platonic mathematics. Additionally, full systems with extended precision execute faster graphical processors units and field-programmable gate arrays because no branching is needed. Sparse equation systems are fast for iterative solvers in a very limited number of cases.

Keywords: Meshless spectrally convergent, partial differential equations, extended arithmetic precision, no branching.

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2071 Effect of Evaporator Temperature on the Performance of Water Desalination/Refrigeration Adsorption System Using AQSOA-ZO2

Authors: Peter G. Youssef, Saad M. Mahmoud, Raya K. Al-Dadah

Abstract:

Many water desalination technologies have been developed but in general they are energy intensive and have high cost and adverse environmental impact. Recently, adsorption technology for water desalination has been investigated showing the potential of using low temperature waste heat (50-85oC) thus reducing energy consumption and CO2 emissions. This work mathematically compares the performance of an adsorption cycle that produces two useful effects namely, fresh water and cooling using two different adsorbents, silica-gel and an advanced zeolite material AQSOA-ZO2, produced by Mitsubishi plastics. It was found that at low chilled water temperatures, typically below 20oC, the AQSOA-Z02 is more efficient than silica-gel as the cycle can produce 5.8 m3 of fresh water per day and 50.1 Rton of cooling per tonne of AQSOA-ZO2. Above 20oC silica-gel is still better as the cycle production reaches 8.4 m3 per day and 62.4 Rton per tonne of silica-gel. These results show the potential of using the AQSOA-Z02 at low chilled water temperature for water desalination and cooling applications.

Keywords: Adsorption, desalination, refrigeration, seawater.

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2070 An Interval Type-2 Dual Fuzzy Polynomial Equations and Ranking Method of Fuzzy Numbers

Authors: Nurhakimah Ab. Rahman, Lazim Abdullah

Abstract:

According to fuzzy arithmetic, dual fuzzy polynomials cannot be replaced by fuzzy polynomials. Hence, the concept of ranking method is used to find real roots of dual fuzzy polynomial equations. Therefore, in this study we want to propose an interval type-2 dual fuzzy polynomial equation (IT2 DFPE). Then, the concept of ranking method also is used to find real roots of IT2 DFPE (if exists). We transform IT2 DFPE to system of crisp IT2 DFPE. This transformation performed with ranking method of fuzzy numbers based on three parameters namely value, ambiguity and fuzziness. At the end, we illustrate our approach by two numerical examples.

Keywords: Dual fuzzy polynomial equations, Interval type-2, Ranking method, Value.

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2069 The Role of Business Survey Measures in Forecasting Croatian Industrial Production

Authors: M. Cizmesija, N. Erjavec, V. Bahovec

Abstract:

While the European Union (EU) harmonized methodology is a benchmark of worldwide used business survey (BS) methodology, the choice of variables that are components of the confidence indicators, as the leading indicators, is not strictly determined and unique. Therefore, the aim of this paper is to investigate and to quantify the relationship between all business survey variables in manufacturing industry and industrial production as a reference macroeconomic series in Croatia. The assumption is that there are variables in the business survey, that are not components of Industrial Confidence Indicator (ICI) and which can accurately (and sometimes better then ICI) predict changes in Croatian industrial production. Empirical analyses are conducted using quarterly data of BS variables in manufacturing industry and Croatian industrial production over the period from the first quarter 2005 to the first quarter 2013. Research results confirmed the assumption: three BS variables which is not components of ICI (competitive position, demand and liquidity) are the best leading indicator then ICI, in forecasting changes in Croatian industrial production instantaneously, with one, two or three quarter ahead.

Keywords: Balance, Business Survey, Confidence Indicators, Industrial Production, Forecasting.

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2068 Pseudo-Homogeneous Kinetic of Dilute-Acid Hydrolysis of Rice Husk for Ethanol Production: Effect of Sugar Degradation

Authors: Megawati, Wahyudi B. Sediawan, Hary Sulistyo, Muslikhin Hidayat

Abstract:

Rice husk is a lignocellulosic source that can be converted to ethanol. Three hundreds grams of rice husk was mixed with 1 L of 0.18 N sulfuric acid solutions then was heated in an autoclave. The reaction was expected to be at constant temperature (isothermal), but before that temperature was achieved, reaction has occurred. The first liquid sample was taken at temperature of 140 0C and repeated every 5 minute interval. So the data obtained are in the regions of non-isothermal and isothermal. It was observed that the degradation has significant effects on the ethanol production. The kinetic constants can be expressed by Arrhenius equation with the frequency factors for hydrolysis and sugar degradation of 1.58 x 105 1/min and 2.29 x 108 L/mole/min, respectively, while the activation energies are 64,350 J/mole and 76,571 J/mole. The highest ethanol concentration from fermentation is 1.13% v/v, attained at 220 0C.

Keywords: degradation, ethanol, hydrolysis, rice husk

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2067 Pseudo-Homogeneous Kinetic of Dilute-Acid Hydrolysis of Rice Huskfor Ethanol Production: Effect of Sugar Degradation

Authors: Megawati, Wahyudi B. Sediawan, Hary Sulistyo, Muslikhin Hidayat

Abstract:

Rice husk is a lignocellulosic source that can be converted to ethanol. Three hundreds grams of rice husk was mixed with 1 L of 0.18 N sulfuric acid solutions then was heated in an autoclave. The reaction was expected to be at constant temperature (isothermal), but before that temperature was achieved, reaction has occurred. The first liquid sample was taken at temperature of 140 0C and repeated every 5 minute interval. So the data obtained are in the regions of non-isothermal and isothermal. It was observed that the degradation has significant effects on the ethanol production. The kinetic constants can be expressed by Arrhenius equation with the frequency factors for hydrolysis and sugar degradation of 1.58 x 105 min-1 and 2.29 x 108 L/mole-min, respectively, while the activation energies are 64,350 J/mole and 76,571 J/mole. The highest ethanol concentration from fermentation is 1.13% v/v, attained at 220 0C.

Keywords: degradation, ethanol, hydrolysis, rice husk.

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2066 Analytical Model for Brine Discharges from a Sea Outfall with Multiport Diffusers

Authors: Anton Purnama

Abstract:

Multiport diffusers are the effective engineering devices installed at the modern marine outfalls for the steady discharge of effluent streams from the coastal plants, such as municipal sewage treatment, thermal power generation and seawater desalination. A mathematical model using a two-dimensional advection-diffusion equation based on a flat seabed and incorporating the effect of a coastal tidal current is developed to calculate the compounded concentration following discharges of desalination brine from a sea outfall with multiport diffusers. The analytical solutions are computed graphically to illustrate the merging of multiple brine plumes in shallow coastal waters, and further approximation will be made to the maximum shoreline's concentration to formulate dilution of a multiport diffuser discharge.

Keywords: Desalination brine discharge, mathematical model, multiport diffuser, two sea outfalls.

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2065 Influence of Strengthening with Perforated Steel Plates on the Behavior of Infill Walls and RC Frame

Authors: Eray Ozbek, Ilker Kalkan, S. Oguzhan Akbas, Sabahattin Aykac

Abstract:

The contribution of the infill walls to the overall earthquake response of a structure is limited and this contribution is generally ignored in the analyses. Strengthening of the infill walls through different techniques has been and is being studied extensively in the literature to increase this limited contribution and the ductilities and energy absorption capacities of the infill walls to create non-structural components where the earthquake-induced energy can be absorbed without damaging the bearing components of the structural frame. The present paper summarizes an extensive research project dedicated to investigate the effects of strengthening the brick infill walls of a reinforced concrete (RC) frame on its lateral earthquake response. Perforated steel plates were used in strengthening due to several reasons, including the ductility and high deformation capacity of these plates, the fire resistant, recyclable and non-cancerogenic nature of mild steel, and the ease of installation and removal of the plates to the wall with the help of anchor bolts only. Furthermore, epoxy, which increases the cost and amount of labor of the strengthening process, is not needed in this technique. The individual behavior of the strengthened walls under monotonic diagonal and lateral reversed cyclic loading was investigated within the scope of the study. Upon achieving brilliant results, RC frames with strengthened infill walls were tested and are being tested to examine the influence of this strengthening technique on the overall behavior of the RC frames. Tests on the wall and frame specimens indicated that the perforated steel plates contribute to the lateral strength, rigidity, ductility and energy absorption capacity of the wall and the infilled frame to a major extent.

Keywords: Infill wall, Strengthening, External plate, Earthquake Behavior.

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2064 A New Analytical Approach for Free Vibration of Membrane from Wave Standpoint

Authors: Mansour Nikkhah-Bahrami, Masih Loghmani, Mostafa Pooyanfar

Abstract:

In this paper, an analytical approach for free vibration analysis of rectangular and circular membranes is presented. The method is based on wave approach. From wave standpoint vibration propagate, reflect and transmit in a structure. Firstly, the propagation and reflection matrices for rectangular and circular membranes are derived. Then, these matrices are combined to provide a concise and systematic approach to free vibration analysis of membranes. Subsequently, the eigenvalue problem for free vibration of membrane is formulated and the equation of membrane natural frequencies is constructed. Finally, the effectiveness of the approach is shown by comparison of the results with existing classical solution.

Keywords: Rectangular and circular membranes, propagation matrix, reflection matrix, vibration analysis.

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2063 A Kinetic Study on the Adsorption of Cd(II) and Zn(II) Ions from Aqueous Solutions on Zeolite NaA

Authors: Dimitar Georgiev, Bogdan Bogdanov, Irena Markovska, Yancho Hristov, Dencho Stanev

Abstract:

The present paper reports the removal of Cd(II) and Zn(II) ions using synthetic Zeolit NaA. The adsorption capacity of the sorbent (Zeolite NaA) strongly depends on simultaneous or not simultaneous (concurrent) presence of Cd(II) and Zn(II) in the sorbate. When Cd(II) and Zn(II) are present simultaneously (concurrently) in the sorbate, Zn(II) ions were sorbed at higher rate. Equilibrium data fitted Langmuir, Freundlich and Tempkin isotherms well. The applicability of the isotherm equation to describe the adsorption process was judged by the correlation coefficients R2. The Langmuir model yielded the best fit with R2 values equal to or higher than 0.970, as compared to the Freundlich and Tempkin models. The fact that 1/n values range from 0.322 to 0.755 indicates that the adsorption of Cd(II) and Zn(II) ions from aqueous solutions also favored by the Freundlich model.

Keywords: Adsorption, adsorption capacity, kinetic sorption, Zeolite NaA

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2062 An Empirical Validation of the Linear- Hyperbolic Approximation of the I-V Characteristic of a Solar Cell Generator

Authors: A. A. Penin

Abstract:

An empirical linearly-hyperbolic approximation of the I - V characteristic of a solar cell is presented. This approximation is based on hyperbolic dependence of a current of p-n junctions on voltage for large currents. Such empirical approximation is compared with the early proposed formal linearly-hyperbolic approximation of a solar cell. The expressions defining laws of change of parameters of formal approximation at change of a photo current of family of characteristics are received. It allows simplifying a finding of parameters of approximation on actual curves, to specify their values. Analytical calculation of load regime for linearly - hyperbolic model leads to quadratic equation. Also, this model allows to define soundly a deviation from the maximum power regime and to compare efficiency of regimes of solar cells with different parameters.

Keywords: a solar cell generator, I − V characteristic, p − n junction, approximation

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2061 Numerical Analysis of Pressure Admission Angle to Vane Angle Ratios on Performance of a Vaned Type Novel Air Turbine

Authors: B.R. Singh, O. Singh

Abstract:

Worldwide conventional resources of fossil fuel are depleting very fast due to large scale increase in use of transport vehicles every year, therefore consumption rate of oil in transport sector alone has gone very high. In view of this, the major thrust has now been laid upon the search of alternative energy source and also for cost effective energy conversion system. The air converted into compressed form by non conventional or conventional methods can be utilized as potential working fluid for producing shaft work in the air turbine and thus offering the capability of being a zero pollution energy source. This paper deals with the mathematical modeling and performance evaluation of a small capacity compressed air driven vaned type novel air turbine. Effect of expansion action and steady flow work in the air turbine at high admission air pressure of 6 bar, for varying injection to vane angles ratios 0.2-1.6, at the interval of 0.2 and at different vane angles such as 30o, 45o, 51.4o, 60o, 72o, 90o, and 120o for 12, 8, 7, 6, 5, 4 and 3 vanes respectively at speed of rotation 2500 rpm, has been quantified and analyzed here. Study shows that the expansion power has major contribution to total power, whereas the contribution of flow work output has been found varying only up to 19.4%. It is also concluded that for variation of injection to vane angle ratios from 0.2 to 1.2, the optimal power output is seen at vane angle 90o (4 vanes) and for 1.4 to 1.6 ratios, the optimal total power is observed at vane angle 72o (5 vanes). Thus in the vaned type novel air turbine the optimum shaft power output is developed when rotor contains 4-5 vanes for almost all situations of injection to vane angle ratios from 0.2 to 1.6.

Keywords: zero pollution, compressed air, air turbine, vaneangle, injection to vane angle ratios

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2060 Characterization of Banana (Musa spp.) Pseudo-Stem and Fruit-Bunch-Stem as a Potential Renewable Energy Resource

Authors: Nurhayati Abdullah, Fauziah Sulaiman, Muhamad Azman Miskam, Rahmad Mohd Taib

Abstract:

Banana pseudo-stem and fruit-bunch-stem are agricultural residues that can be used for conversion to bio-char, biooil, and gases by using thermochemical process. The aim of this work is to characterize banana pseudo-stem and banana fruit-bunch-stem through proximate analysis, elemental analysis, chemical analysis, thermo-gravimetric analysis, and heating calorific value. The ash contents of the banana pseudo-stem and banana fruit-bunch-stem are 11.0 mf wt.% and 20.6 mf wt.%; while the carbon content of banana pseudo-stem and fruit-bunch-stem are 37.9 mf wt.% and 35.58 mf wt.% respectively. The molecular formulas for banana stem and banana fruit-bunch-stem are C24H33NO26 and C19H29NO33 respectively. The measured higher heating values of banana pseudostem and banana fruit-bunch-stem are 15.5MJ/kg and 12.7 MJ/kg respectively. By chemical analysis, the lignin, cellulose, and hemicellulose contents in the samples will also be presented. The feasibility of the banana wastes to be a feedstock for thermochemical process in comparison with other biomass will be discussed in this paper.

Keywords: Banana Waste, Biomass, Renewable Energy, Thermo-chemical Characteristics.

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2059 Antecedents and Consequences of Social Media Adoption in Travel and Tourism: Evidence from Customers and Industry

Authors: Mohamed A. Abou-Shouk, Mahamoud M. Hewedi

Abstract:

This study extends technology acceptance model (TAM) to investigate the antecedents and consequences of social media adoption by tourists and travel agents. It compares their perceptions on social media adoption and its consequences. Online survey was addressed to tourists and travel agents for data collection purposes. Structural equation modelling was employed for analysis purposes. The findings revealed that the majority of tourists and travel agents involved in the study believe in the usefulness of social media adoption for travel planning and marketing purposes. They agree that adopting social media could change the attitude of tourists towards specific destination or attraction and influence their purchasing decisions. This study contributes to knowledge by extending TAM and provides some managerial implication to marketers.

Keywords: TAM, social media, travel, tourism, travel agents.

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2058 Stability and HOPF Bifurcation Analysis in a Stage-structured Predator-prey system with Two Time Delays

Authors: Yongkun Li, Meng Hu

Abstract:

A stage-structured predator-prey system with two time delays is considered. By analyzing the corresponding characteristic equation, the local stability of a positive equilibrium is investigated and the existence of Hopf bifurcations is established. Formulae are derived to determine the direction of bifurcations and the stability of bifurcating periodic solutions by using the normal form theory and center manifold theorem. Numerical simulations are carried out to illustrate the theoretical results. Based on the global Hopf bifurcation theorem for general functional differential equations, the global existence of periodic solutions is established.

Keywords: Predator-prey system, stage structure, time delay, HOPF bifurcation, periodic solution, stability.

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2057 Range-Free Localization Schemes for Wireless Sensor Networks

Authors: R. Khadim, M. Erritali, A. Maaden

Abstract:

Localization of nodes is one of the key issues of Wireless Sensor Network (WSN) that gained a wide attention in recent years. The existing localization techniques can be generally categorized into two types: range-based and range-free. Compared with rang-based schemes, the range-free schemes are more costeffective, because no additional ranging devices are needed. As a result, we focus our research on the range-free schemes. In this paper we study three types of range-free location algorithms to compare the localization error and energy consumption of each one. Centroid algorithm requires a normal node has at least three neighbor anchors, while DV-hop algorithm doesn’t have this requirement. The third studied algorithm is the amorphous algorithm similar to DV-Hop algorithm, and the idea is to calculate the hop distance between two nodes instead of the linear distance between them. The simulation results show that the localization accuracy of the amorphous algorithm is higher than that of other algorithms and the energy consumption does not increase too much.

Keywords: Wireless Sensor Networks, Node Localization, Centroid Algorithm, DV–Hop Algorithm, Amorphous Algorithm.

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2056 Aesthetics and Robotics: Which Form to give to the Human-Like Robot?

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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2055 Creeping Insulation - Hong Kong Green Wall

Authors: X. L. Zhang, K. L. Li, R. M. Skitmore

Abstract:

Hong Kong is a densely populated city suffering badly from the urban heat island effect. Green wall offers a means of ameliorating the situation but there are doubts over its suitability in Hong Kong’s unique environment. In this paper, we look at the potential for green walls in Hong Kong first by summarizing some of the Chinese green walling systems and associated vegetation in use, then by an introduction to three existing green walls in Hong Kong, and finally through a small experiment aimed at identifying the likely main effects of green walled housing.

The results indicate that green walling in Hong Kong is likely to provide enhanced internal house environment in terms of warm weather temperature reduction, stabilization and damping, with direct energy savings in air-conditioning and indirect district benefits of reduced heat island effect and carbon emissions. The green walling insulation properties also suggest the possibility of warmer homes in winter and/or energy savings in mechanical heating provision.

Keywords: Case studies, experiment, green wall, Hong Kong.

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2054 A New Self-Tuning Fuzzy PD Controller of a BDFIG for Wind Energy Conversion

Authors: Zoheir Tir, Rachid Abdessemed

Abstract:

This paper presents a new control scheme to control a brushless doubly fed induction generator (BDFIG) using back-to-back PWM converters for wind power generation. The proposed control scheme is a New Self-Tuning Fuzzy Proportional-Derivative Controller (NSTFPDC). The goal of BDFIG control is to achieve a similar dynamic performance to the doubly fed induction generator (DFIG), exploiting the well-known induction machine vector control philosophy. The performance of NSTFPDC controller has been investigated and compared with the two controllers, called Proportional–Integral (PI) and PD-like Fuzzy Logic controller (PD-like FLC) based BDFIG. The simulation results demonstrate the effectiveness and the robustness of the NSTFPDC controller.

Keywords: Brushless Doubly Fed Induction Generator (BDFIG), PI controller, PD-like Fuzzy Logic controller, New Self-Tuning Fuzzy Proportional-Derivative Controller (NSTFPDC), Scaling factor, back-to-back PWM converters, wind energy system.

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2053 Floating Offshore Wind: A Review of Installation Vessel Requirements

Authors: A. P. Crowle

Abstract:

Floating offshore wind farms may provide in the future large quantities of renewable energy. One of the challenges to their future development is the provision of installation vessels for the offshore installation of floating wind turbines. This paper examines the current fleet of vessels that can be used for inshore construction. Separate vessels are required for the ocean tow out and the offshore installation. Information will be provided on what new vessels might be required to improve the efficiency and reduce costs of installing floating wind turbines. Specialized cargo vessels are required for this initial mobilization. Anchor handling vessels are required to tow the floating wind turbine offshore and to install and connect the moorings. Subsea work vessels are required to install the dynamic cables whilst cable lay vessels are required for the export power cable. This paper reviews the existing and future installation vessel requirement for floating wind. Dedicated ports are required for vertical integration of the substructure and the tower, nacelle and blades.

Keywords: Floating wind, naval architecture, offshore installation vessels, ports for renewable energy.

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2052 The Measurement of Endogenous Higher-Order Formative Composite Variables in PLS-SEM: An Empirical Application from CRM System Development

Authors: Samppa Suoniemi, Harri Terho, Rami Olkkonen

Abstract:

In recent methodological articles related to structural equation modeling (SEM), the question of how to measure endogenous formative variables has been raised as an urgent, unresolved issue. This research presents an empirical application from the CRM system development context to test a recently developed technique, which makes it possible to measure endogenous formative constructs in structural models. PLS path modeling is used to demonstrate the feasibility of measuring antecedent relationships at the formative indicator level, not the formative construct level. Empirical results show that this technique is a promising approach to measure antecedent relationships of formative constructs in SEM.

Keywords: CRM system development, formative measures, PLS path modeling, research methodology.

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2051 Crowdfunding for Saudi Arabia Green Projects

Authors: Saleh Komies, Mona Alharbi, Razan Alhayyani, Mozah Almulhim, Roseanne Khawaja, Ahmed Alradhi

Abstract:

One of the proposed solutions that face some challenges is encouraging sustainable energy consumption across Saudi Arabia through crowdfunding platforms. To address these challenges, we need to determine the level of awareness of crowdfunding and green projects, as well as the preferences and willingness of Saudis to utilize crowdfunding as an alternative funding source for green projects in Saudi Arabia. In this study, we aim to determine the influence of environmental awareness and concern on the propensity to crowdfund green projects. The survey is being conducted as part of environmental initiatives to assess public perceptions and opinions on crowdfunding green projects in Saudi Arabia. A total of 450 responses to an online questionnaire distributed via convenience and snowball sampling were utilized for data analysis. The survey reveals that Saudis have a low understanding of crowdfunding concepts and a relatively high understanding of implementing green projects. The public is interested in crowdfunding green projects if there is a return on investment.

Keywords: Crowdfunding, green projects, renewable energy, Saudi Arabia, solar farms, wind resources.

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2050 Collaborative Business Strategy of PTT Energy Trading Co. Ltd. for LNG form of Coal Bed Methane in B2B Transaction to Japanese Shareholder, Especially to Electricity and Power Supply Companies

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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2049 Summarizing Data Sets for Data Mining by Using Statistical Methods in Coastal Engineering

Authors: Yunus Doğan, Ahmet Durap

Abstract:

Coastal regions are the one of the most commonly used places by the natural balance and the growing population. In coastal engineering, the most valuable data is wave behaviors. The amount of this data becomes very big because of observations that take place for periods of hours, days and months. In this study, some statistical methods such as the wave spectrum analysis methods and the standard statistical methods have been used. The goal of this study is the discovery profiles of the different coast areas by using these statistical methods, and thus, obtaining an instance based data set from the big data to analysis by using data mining algorithms. In the experimental studies, the six sample data sets about the wave behaviors obtained by 20 minutes of observations from Mersin Bay in Turkey and converted to an instance based form, while different clustering techniques in data mining algorithms were used to discover similar coastal places. Moreover, this study discusses that this summarization approach can be used in other branches collecting big data such as medicine.

Keywords: Clustering algorithms, coastal engineering, data mining, data summarization, statistical methods.

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