Search results for: Comfort temperature

Authors: Ali Eltayeb Muhsin, Mohamed Elhadi Elsari

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The substrate heater designed for this investigation is a front side substrate heating system. It consists of 10 conventional tungsten halogen lamps and an aluminum reflector, total input electrical power of 5 kW. The substrate is heated by means of a radiation from conventional tungsten halogen lamps directed to the substrate through a glass window. This design allows easy replacement of the lamps and maintenance of the system. Within 2 to 6 minutes the substrate temperature reaches 500 to 830 C by varying the vertical distance between the glass window and the substrate holder. Moreover, the substrate temperature can be easily controlled by controlling the input power to the system. This design gives excellent opportunity to deposit many deferent films at deferent temperatures in the same deposition time. This substrate heater was successfully used for Chemical Vapor Deposition (CVD) of many thin films, such as Silicon, iron, etc.

Keywords: CVD, Halogen Lamp, Substrate Heater, Thin Films.

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Authors: H. Golchoobian, S. Saedodin, M. H. Taheri, A. Sarafraz

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In this paper, natural convection in an attic is numerically investigated. The geometry of the problem is considered to be a triangular enclosure. ANSYS Fluent software is used for modeling and numerical solution. This study is for steady state. Four right-angled triangles with height to base ratios of 2, 1, 0.5 and 0.25 are considered. The behavior of various parameters related to its performance, including temperature distribution and velocity vectors are evaluated, and graphs for the Nusselt number have been drawn. Also, in this study, the effect of geometric shape of enclosure with different height-to-base ratios has been evaluated for three types of boundary conditions of winter, summer day and one another state. It can be concluded that as the bottom side temperature and ratio of base to height of the enclosure increases, the convective effects become more prominent and circulation happened.

Keywords: Enclosure, natural convection, numerical solution, Nusselt number, triangular.

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Authors: Yassine Meraihi, Dalila Acheli, Rabah Meraihi

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Vehicular Ad hoc Network (VANET) is a special case of Mobile Ad hoc Network (MANET) used to establish communications and exchange information among nearby vehicles and between vehicles and nearby fixed infrastructure. VANET is seen as a promising technology used to provide safety, efficiency, assistance and comfort to the road users. Routing is an important issue in Vehicular Ad Hoc Network to find and maintain communication between vehicles due to the highly dynamic topology, frequently disconnected network and mobility constraints.

This paper evaluates the performance of two most popular proactive routing protocols OLSR and DSDV in real city traffic scenario on the basis of three metrics namely Packet delivery ratio, throughput and average end to end delay by varying vehicles density and transmission range.

Keywords: DSDV, OLSR, Quality of service, Routing protocols, VANET.

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Authors: Wang Jing, Tao Tao, Li Xiyuan, Pei Yifei

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How to simulate experimentally the air flow and heat transfer under microgravity on the ground is important, which has not been completely solved so far. Influence of gravity on air natural convection results in convection heat transfer on ground difference from that on orbit. In order to obtain air temperature and velocity deviations of manned spacecraft during terrestrial thermal test, dimensionless number analysis and numerical simulation analysis are performed. The calculated temperature distribution and velocity distribution of the horizontal test cases are compared to the vertical cases. The results show that the influence of gravity is neglected for facility drawer racks and more obvious for vertical cabins.

Keywords: Gravity, Convection heat transfer, Manned spacecraft, Dimensionless number, Numerical simulation

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Authors: Umpawan Satitthai, Apanee Luengnaruemitchai, Erdogan Gulari

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In this study, oxidative steam reforming of methanol (OSRM) over a Au/CeO2–Fe2O3 catalyst prepared by a depositionprecipitation (DP) method was studied to produce hydrogen in order to feed a Proton Exchange Membrane Fuel Cell (PEMFC). The support (CeO2, Fe2O3, and CeO2–Fe2O3) were prepared by precipitation and co-precipitation methods. The impact of the support composition on the catalytic performance was studied by varying the Ce/(Ce+Fe) atomic ratio, it was found that the 1%Au/CF(0.25) calcined at 300 °C exhibited the highest catalytic activity in the whole temperature studied. In addition, the effect of Au content was investigated and 3%Au/CF(0.25) exhibited the highest activity under the optimum condition in the temperature range of 200 °C to 400 °C. The catalysts were characterized by various techniques: XRD, TPR, XRF, and UV-vis.

Keywords: CeO2, Fe2O3, Gold catalyst, Hydrogen production, Methanol, Oxidative steam reforming.

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Authors: Biswajit Biswas

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Demand of energy is increasing faster than the generation. It leads shortage of power in all sectors of society. At peak hours this shortage is higher. Unless we utilize energy efficient technology, it is very difficult to minimize the shortage of energy. So energy efficiency program and energy conservation has an important role. Energy efficient technologies are cost intensive hence it is always not possible to implement in country like India. In the recent study, an educational building with operating hours from 10:00 a.m. to 05:00 p.m. has been selected to quantify the possibility of lighting energy conservation. As the operating hour is in daytime, integration of daylight with artificial lighting system will definitely reduce the lighting energy consumption. Moreover the initial investment has been given priority and hence the existing lighting installation was unaltered. An automatic controller has been designed which will be operated as a function of daylight through windows and the lighting system of the room will function accordingly. The result of the study of integrating daylight gave quite satisfactory for visual comfort as well as energy conservation.

Keywords: Lighting energy, energy efficiency, daylight, illumination, energy conservation.

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Authors: M. N. Eshtiaghi, N. Yoswathana

Abstract:

The aim of this study was to extract sugar from sugarcane using high electric field pulse (HELP) as a non-thermal cell permeabilization method. The result of this study showed that it is possible to permeablize sugar cane cells using HELP at very short times (less than 10 sec.) and at room temperature. Increasing the field strength (from 0.5kV/cm to 2kV/cm) and pulse number (1 to 12) led to increasing the permeabilization of sugar cane cells. The energy consumption during HELP treatment of sugar cane (2.4 kJ/kg) was about 100 times less compared to thermal cell disintegration at 85 <=C (about 271.7 kJ/kg). In addition, it was possible to extract sugar cane at a moderate temperature (45 <=C) using HELP pretreatment. With combination of HELP pretreatment followed by thermal extraction at 75 <=C, extraction resulted in up to 3% more sugar (on the basis of total extractable sugar) compared to samples without HELP pretreatment.

Keywords: Cell permeabilization, High electric field pulses, Non-thermal processing, Sugar cane extraction.

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Authors: Eiko Takaoka, Ryohei Takahashi, Takashi Toyoda

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We installed solar panels and digital meteorological equipments whose electrical power is supplied using PV on July 13, 2011. Then, the relationship between the electric power generation and the irradiation, air temperature, and wind velocity was investigated on a roof at a university. The electrical power generation, irradiation, air temperature, and wind velocity were monitored over two years. By analyzing the measured meteorological data and electric power generation data using PTC, we calculated the size of the solar panel that is most suitable for this system. We also calculated the wasted power generation using PTC with the measured meteorological data obtained in this study. In conclusion, to reduce the "wasted power generation", a smaller-size solar panel is required for stable operation.

Keywords: Digital meteorological equipments, PV, photovoltaic, irradiation, PTC.

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Authors: Thipsalin Poontaweegeratigarn, Sumaeth Chavadej, Pramoch Rangsunvigit

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In this work, biohydrogen production via dark fermentation from alcohol wastewater using upflow anaerobic sludge blanket reactors (UASB) with a working volume of 4 L was investigated to find the optimum conditions for a maximum hydrogen yield. The system was operated at different COD loading rates (23, 31, 46 and 62 kg/m3d) at mesophilic temperature (37 ºC) and pH 5.5. The seed sludge was pretreated before being fed to the UASB system by boiling at 95 ºC for 15 min. When the system was operated under the optimum COD loading rate of 46 kg/m3d, it provided the hydrogen content of 27%, hydrogen yield of 125.1 ml H2/g COD removed and 95.1 ml H2/g COD applied, hydrogen production rate of 18 l/d, specific hydrogen production rate of 1080 ml H2/g MLVSS d and 1430 ml H2/ L d, and COD removal of 24%.

Keywords: Hydrogen production, Upflow anaerobic sludge blanket reactor (UASB), Optimum condition, Alcohol wastewater

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Authors: Alla V. Goncharova, Tatyana A. Karpenyuk, Yana S. Tsurkan, Rosa U. Beisembaeva, Togzhan D. Mukasheva, Ludmila V. Ignatova, Ramza Z. Berzhanova

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In this work the effect of culturing conditions of filamentous fungi Penicillium raistrickii, Penicillium anatolicum, Fusarium sp. on biomass yield, the content of total lipids and fatty acids was studied. It has been established that in time the process of lipids accumulation correlated with biomass growth of cultures, reaching maximum values in stationary growth phase.

Biomass yield and accumulation of general lipids was increased by adding zinc to the culture medium. The more intensive accumulation of biomass and general lipids was observed at temperature 18°C. Lowering the temperature of culturing has changed the ratio of saturated: Unsaturated fatty acids in the direction of increasing the latter.

Keywords: Biomass, culturing conditions, fungi, fatty acids (FA), growth dynamics, lipids.

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Authors: Imane Khalil, Quinn Pratt

Abstract:

In a nuclear reactor, an array of fuel rods containing stacked uranium dioxide pellets clad with zircalloy is the heat source for a thermodynamic cycle of energy conversion from heat to electricity. After fuel is used in a nuclear reactor, the assemblies are stored underwater in a spent nuclear fuel pool at the nuclear power plant while heat generation and radioactive decay rates decrease before it is placed in packages for dry storage or transportation. A computational model of a Boiling Water Reactor spent fuel assembly is modeled using FLUENT, the computational fluid dynamics package. Heat transfer simulations were performed on the two-dimensional 9x9 spent fuel assembly to predict the maximum cladding temperature for different input to the FLUENT model. Uncertainty quantification is used to predict the heat transfer and the maximum temperature profile inside the assembly.

Keywords: Spent nuclear fuel, conduction, heat transfer, uncertainty quantification.

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Authors: S. Chauhan, T. P. K. Grewal, S. K. Agrawal, V. K. Srivastava

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Combustion of fuels in industrial and transport sector has lead to an alarming release of polluting gases to the atmosphere. Carbon monoxide is one such pollutant, which is formed as a result of incomplete oxidation of the fuel. In order to analyze the effect of catalyst on the reduction of CO emissions to the atmosphere, two catalysts Mn2O3 and Hopcalite are considered. A model was formed based on mass and energy balance equations. Results show that Hopcalite catalyst as compared to Mn2O3 catalyst helped in faster conversion of the polluting gas as the operating temperature of the hopcalite catalyst is much lower as compared to the operating temperature of Mn2O3 catalyst.

Keywords: Carbon monoxide, modeling, hopcalite, manganese oxide.

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Authors: S. Sabzchi Asl, N. Tahouni, M. H. Panjeshahi

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Benchmarking of a process with respect to energy consumption, without accomplishing a full retrofit study, can save both engineering time and money. In order to achieve this goal, the first step is to develop a conceptual-mathematical model that can easily be applied to a group of similar processes. In this research, we have aimed to identify a set of key parameters for the model which is supposed to be used for benchmarking of combined cycle power plants. For this purpose, three similar combined cycle power plants were studied. The results showed that ambient temperature, pressure and relative humidity, number of HRSG evaporator pressure levels and relative power in part load operation are the main key parameters. Also, the relationships between these parameters and produced power (by gas/ steam turbine), gas turbine and plant efficiency, temperature and mass flow rate of the stack flue gas were investigated.

Keywords: Combined cycle power plant, energy benchmarking, modelling, Retrofit.

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Authors: M. M. Manyuchi, A. Phiri, P. Muredzi, T. Chitambwe

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Vermicomposting is the conversion of organic waste into bio-fertilizers through the action of earthworm. This technology is widely used for organic solid waste management. Waste corn pulp blended with cow dung manure was vermicomposted over 30 days using Eisenia fetida earthworms species. pH, temperature, moisture content, and electrical conductivity were daily monitored. The feedstock, vermicompost and vermiwash were analyzed for nutrient composition. The average temperature and moisture content in the vermi-reactor was 22.5°C and 42.5% respectively. The vermicompost and vermiwash had an almost neutral pH whilst the electrical conductivity was 21% higher in the vermicompost. The nitrogen and potassium content was 57% and 79.6% richer in the vermicompost respectively compared to the vermiwash. However, the vermiwash was 84% richer in phosphorous as compared to vermicompost. Furthermore, the vermiwash was 89.1% and 97.6% richer in Ca and Mg respectively and was 97.8% richer in Na salts compared to the vermicompost. The vermiwash also indicated a significantly higher amount of micronutrients. Both bio-fertilizers were rich in nutrients specification for fertilizers.

Keywords: Vermicompost, vermiwash, nutrient composition.

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Authors: Nuttawan Yoswathana, M. N. Eshtiaghi

Abstract:

Rambutan is a tropical fruit which peel possesses antioxidant properties. This work was conducted to optimize extraction conditions of phenolic compounds from rambutan peel. Response surface methodology (RSM) was adopted to optimize subcritical water extraction (SWE) on temperature, extraction time and percent solvent mixture. The results demonstrated that the optimum conditions for SWE were as follows: temperature 160°C, extraction time 20min. and concentration of 50% ethanol. Comparison of the phenolic compounds from the rambutan peels in maceration 6h, soxhlet 4h, and SWE 20min., it indicated that total phenolic content (using Folin-Ciocalteu-s phenol reagent) was 26.42, 70.29, and 172.47mg of tannic acid equivalent (TAE) per g dry rambutan peel, respectively. The comparative study concluded that SWE was a promising technique for phenolic compounds extraction from rambutan peel, due to much more two times of conventional techniques and shorter extraction times.

Keywords: Subcritical water extraction, Rambutan peel, phenolic compounds, response surface methodology

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Authors: M. S. Kaiser

Abstract:

An attempt has been made to determine the strength and impact properties of Cr-Mo steel weld and base materials by varying the current during manual metal arc welding. Toughness over a temperature range from -32 to 100°C of base, heat affected zone (HAZ) and weld zones at three current settings are made. It is observed that the deterioration in notch toughness at any zone with the temperature decreases. The values of notch toughness for all zones at -32°C are almost same for any current settings. The values of notch toughness at HAZ area are higher than that of weld area due to the coarsening of ferrite grain of HAZ occurs with higher heat input. From microhardness and microstructure result, it can be concluded that large inclusion content in weld deposit is the cause of lower notch toughness value.

Keywords: Chromium-Molybdenum steel, post-weld heat treatment, heat affected zone, microstructure.

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Authors: M. Shahina, K. Fakruddin, C. M. Subhan, S. Rangappa

Abstract:

In this work, two mixtures with equal concentrations of 1) 4ꞌ-(6-(4-(pentylamino) methyl)-3-hydroxyphenoxy) hexyloxy) biphenyl-4-carbonitrile+-4-((4-(hexyloxy) benzylidene) amino) phenyl 4-butoxy benzoate and 2) 4ꞌ - (6-(4-(hexylamino) methyl)-3-hydroxyphenoxy) hexyloxy) biphenyl-4-carbonitrile+-4-((4-(octyloxy) benzylidene) amino) phenyl 4-butoxy benzoate, have been prepared. The transition temperature and optical texture are observed by using thermal microscopy. Density and birefringence studies are carried out on the above liquid crystalline mixtures. Using density and refractive indices data, the molecular polarizabilities are evaluated by using well-known Vuks and Neugebauer models. The molecular polarizability is also evaluated theoretically by Lippincott δ function model. The results reveal that the polarizability values are same in both experimental and theoretical methods.

Keywords: Liquid crystals, optical textures, transition temperature, birefringence, polarizability.

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Authors: N. Tugrul, N. Baran Acarali, A. S. Kipcak, E. Moroydor Derun, S. Piskin

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Turkey has 72 % of total world boron reserves on the basis of B2O3.Borates that is a refined form of boron minerals have a wide range of applications. Zinc borates can be used as multifunctional synergistic additives. The most important properties are low solubility in water and high dehydration temperature. Zinc borates dehydrate above 290°C and anhydrous zinc borate has thermal resistance about 400°C. Zinc borates can be synthesized using several methods such as hydrothermal and solid-state processes. In this study, the solid-state method was applied between 500 and 800°C using the starting materials of ZnO and H3BO3 with 1:4 mole ratio. The reaction time was determined as 4 hours after some preliminary experiments. After the synthesis, the crystal structure and the morphology of the products were examined by XRay Diffraction (XRD), Fourier Transform Infrared Spectroscopy (FT-IR) and Raman Spectrometer. As a result the form of ZnB4O7 was synthesized with the highest crystal score at 800°C.

Keywords: Raman, solid-state method, zinc borate, XRD.

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Authors: R. Eslami Farsani, A. Shokuhfar, A. Sedghi

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Carbon fibers are fabricated from different materials, such as special polyacrylonitrile (PAN) fibers, rayon fibers and pitch. Among these three groups of materials, PAN fibers are the most widely used precursor for the manufacture of carbon fibers. The process of fabrication carbon fibers from special PAN fibers includes two steps; oxidative stabilization at low temperature and carbonization at high temperatures in an inert atmosphere. Due to the high price of raw materials (special PAN fibers), carbon fibers are still expensive. In the present work the main goal is making carbon fibers from low price commercial PAN fibers with modified chemical compositions. The results show that in case of conducting completes stabilization process, it is possible to produce carbon fibers with desirable tensile strength from this type of PAN fibers. To this matter, thermal characteristics of commercial PAN fibers were investigated and based upon the obtained results, with some changes in conventional procedure of stabilization in terms of temperature and time variables; the desirable conditions of complete stabilization is achieved.

Keywords: Modified Commercial PAN Fibers, Stabilization, Carbonization, Carbon Fibers.

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Authors: Jeong-Hyeon Kim, Ki-Yeob Kang, Myung-Hyun Kim, Jae-Myung Lee

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Primary barrier of membrane type LNG containment system consist of corrugated 304L stainless steel. This 304L stainless steel is austenitic stainless steel which shows different material behaviors owing to phase transformation during the plastic work. Even though corrugated primary barriers are subjected to significant amounts of pre-strain due to press working, quantitative mechanical behavior on the effect of pre-straining at cryogenic temperatures are not available. In this study, pre-strain level and pre-strain temperature dependent tensile tests are carried to investigate mechanical behaviors. Also, constitutive equations with material parameters are suggested for a verification study.

Keywords: Constitutive equation, corrugated sheet, pre-strain effect, elasto-visco-plastic-damage model, 304L stainless steel.

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Authors: V. D. Thi, M. Li, M. Khelifa, M. El Ganaoui, Y. Rogaume

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This paper presents a two-dimensional model to study the heat and moisture transfer through porous building materials. Dynamic and static coupled models of heat and moisture transfer in porous material under low temperature are presented and the coupled models together with variable initial and boundary conditions have been considered in an analytical way and using the finite element method. The resulting coupled model is converted to two nonlinear partial differential equations, which is then numerically solved by an implicit iterative scheme. The numerical results of temperature and moisture potential changes are compared with the experimental measurements available in the literature. Predicted results demonstrate validation of the theoretical model and effectiveness of the developed numerical algorithms. It is expected to provide useful information for the porous building material design based on heat and moisture transfer model.

Keywords: Finite element method, heat transfer, moisture transfer, porous materials, wood.

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Authors: S. Niksarlioglu, F. Kulahci

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Earthquakes are natural phenomena that occur with influence of a lot of parameters such as seismic activity, changing in the ground waters' motion, changing in the water-s temperature, etc. On the other hand, the radon gas concentrations in soil vary as nonlinear generally with earthquakes. Continuous measurement of the soil radon gas is very important for determination of characteristic of the seismic activity. The radon gas changes as continuous with strain occurring within the Earth-s surface during an earthquake and effects from the physical and the chemical processes such as soil structure, soil permeability, soil temperature, the barometric pressure, etc. Therefore, at the modeling researches are notsufficient to knowthe concentration ofradon gas. In this research, we determined relationships between radon emissions based on the environmental parameters and earthquakes occurring along the East Anatolian Fault Zone (EAFZ), Turkiye and predicted magnitudes of some earthquakes with the artificial neural network (ANN) model.

Keywords: Earthquake, Modeling, Prediction, Radon.

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Authors: Zhaojun Wang, Zongdi Sun, Qinqin Cui, Xingwan Ren

Abstract:

Based on multivariate statistical analysis theory, this paper uses the principal component analysis method, Mahalanobis distance analysis method and fitting method to establish the photovoltaic health model to evaluate the health of photovoltaic panels. First of all, according to weather conditions, the photovoltaic panel variable data are classified into five categories: sunny, cloudy, rainy, foggy, overcast. The health of photovoltaic panels in these five types of weather is studied. Secondly, a scatterplot of the relationship between the amount of electricity produced by each kind of weather and other variables was plotted. It was found that the amount of electricity generated by photovoltaic panels has a significant nonlinear relationship with time. The fitting method was used to fit the relationship between the amount of weather generated and the time, and the nonlinear equation was obtained. Then, using the principal component analysis method to analyze the independent variables under five kinds of weather conditions, according to the Kaiser-Meyer-Olkin test, it was found that three types of weather such as overcast, foggy, and sunny meet the conditions for factor analysis, while cloudy and rainy weather do not satisfy the conditions for factor analysis. Therefore, through the principal component analysis method, the main components of overcast weather are temperature, AQI, and pm2.5. The main component of foggy weather is temperature, and the main components of sunny weather are temperature, AQI, and pm2.5. Cloudy and rainy weather require analysis of all of their variables, namely temperature, AQI, pm2.5, solar radiation intensity and time. Finally, taking the variable values in sunny weather as observed values, taking the main components of cloudy, foggy, overcast and rainy weather as sample data, the Mahalanobis distances between observed value and these sample values are obtained. A comparative analysis was carried out to compare the degree of deviation of the Mahalanobis distance to determine the health of the photovoltaic panels under different weather conditions. It was found that the weather conditions in which the Mahalanobis distance fluctuations ranged from small to large were: foggy, cloudy, overcast and rainy.

Keywords: Fitting, principal component analysis, Mahalanobis distance, SPSS, MATLAB.

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Authors: B. Belfuguais, S. Larbi

Abstract:

The work presented in this study is related to an energy system analysis based on passive cooling system for dwellings. It consists to solar chimney energy performances determination versus geometrical and environmental considerations as the size and inlet width conditions of the chimney. Adrar site located in the southern region of Algeria is chosen for this study according to ambient temperature and solar irradiance technical data availability. Obtained results are related to the glazing temperature distributions, the chimney air flow and internal wall temperatures. The air room change per hour (ACH) parameter, the outlet air velocity and mass air flow rate are also determined. It is shown that the chimney width has a significant effect on energy performances compared to its entry size. A good agreement is observed between these results and those obtained by others from the literature.

Keywords: Solar chimney, Energy performances, Passive ventilation, Numerical simulation

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Authors: Laith Jaafer Habeeb

Abstract:

The present study is concerned with the free convective two dimensional flow and heat transfer, within the framework of Boussinesq approximation, in anisotropic fluid filled porous rectangular enclosure subjected to end-to-end temperature difference have been investigated using Lattice Boltzmann method fornon-Darcy flow model. Effects of the moving lid direction (top, bottom, left, and right wall moving in the negative and positive x&ydirections), number of moving walls (one or two opposite walls), the sliding wall velocity, and four different constant temperatures opposite walls cases (two surfaces are being insulated and the twoother surfaces areimposed to be at constant hot and cold temperature)have been conducted. The results obtained are discussed in terms of the Nusselt number, vectors, contours, and isotherms.

Keywords: Numerical simulation, lid-driven cavity flow, saturated porous medium, different velocity and heated walls.

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Authors: G.Durai, N.Rajamohan, C.Karthikeyan, M.Rajasimman

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In this study, aerobic digestion of tannery industry wastewater was carried out using mixed culture obtained from common effluent treatment plant treating tannery wastewater. The effect of pH, temperature, inoculum concentration, agitation speed and initial substrate concentration on the reduction of organic matters were found. The optimum conditions for COD reduction was found to be pH - 7 (60%), temperature - 30ÔùªC (61%), inoculum concentration - 2% (61%), agitation speed - 150rpm (65%) and initial substrate concentration - 1560 mg COD/L (74%). Kinetics studies were carried by using Monod model, First order, Diffusional model and Singh model. From the results it was found that the Monod model suits well for the degradation of tannery wastewater using mixed microbial consortium.

Keywords: Tannery, Wastewater, Biological treatment, Aerobic, Mixed culture, Kinetics.

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Authors: Carlos Machado, José A. Mendes

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Home Automation is a field that, among other subjects, is concerned with the comfort, security and energy requirements of private homes. The configuration of automatic functions in this type of houses is not always simple to its inhabitants requiring the initial setup and regular adjustments. In this work, the ubiquitous computing system vision is used, where the users- action patterns are captured, recorded and used to create the contextawareness that allows the self-configuration of the home automation system. The system will try to free the users from setup adjustments as the home tries to adapt to its inhabitants- real habits. In this paper it is described a completely automated process to determine the light state and act on them, taking in account the users- daily habits. Artificial Neural Network (ANN) is used as a pattern recognition method, classifying for each moment the light state. The work presented uses data from a real house where a family is actually living.

Keywords: ANN, Home Automation, Neural Systems, PatternRecognition, Ubiquitous Computing.

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Authors: Rosina C. Chia, Elmer Poe, Karl L. Wuensch

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A virtual collaborative classroom was created at East Carolina University, using videoconference technology via regular internet to bring students from 18 different countries, 2 at a time, to the ECU classroom in real time to learn about each other-s culture. Students from two countries are partnered one on one, they meet for 4-5 weeks, and submit a joint paper. Then the same process is repeated for two other countries. Lectures and student discussions are managed with pre-determined topics and questions. Classes are conducted in English and reading assignments are placed on the website. Administratively all partners are independent, students pay fees and get credits at their home institution. Familiarity with technology, knowledge in cultural understanding and attitude change were assessed, only attitude changes are reported in this paper. After taking this course, all students stated their comfort level in working with, and their desire to interact with, culturally different others grew stronger and their xenophobia and isolationist attitudes decreased.

Keywords: Attitude change, interactive cultural learning, multicultural education, real time virtual learning.

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Authors: Musaida M. M. Manyuchi, Anthony Phiri, Ngoni Chirinda, Perkins Muredzi, Joseph Govhaand, Thamary Sengudzwa

Abstract:

Waste corn pulp was investigated as a potential feedstock during vermicomposting using Eisenia fetida. Corn pulp is the major staple food in Southern Africa and constitutes about 25% of the total organic waste. Wastecooked corn pulp was blended with cow dung in the ratio 6:1 respectively to optimize the vermicomposting process. The feedstock was allowed to vermicompost for 30 days. The vermicomposting took place in a 3- tray plastic worm bin. Moisture content, temperature, pH, and electrical conductivity were monitoreddaily. The NPK content was determined at day 30. During vermicomposting, moisture content increased from 27.68% to 52.41%, temperature ranged between 19- 25◦C, pH increased from 5.5 to 7.7, and electrical conductivity decreased from 80000μS/cm to 60000μS/cm. The ash content increased from 11.40% to 28.15%; additionally the volatile matter increased from 1.45% to 10.02%. An odorless, dark brown vermicompost was obtained. The vermicompost NPK content was 4.19%, 1.15%, and 6.18% respectively.

Keywords: Corn pulp, Eisenia fetida, vermicomposting, waste management.

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Authors: Kyung-Tae Kwon, Md. Salim Uddin, Go-Woon Jung, Jeong-Eun Sim, Byung-Soo Chun

Abstract:

Supercritical carbon dioxide (SC-CO2) was used as a solvent to extract oil from wheat bran. Extractions were carried out in a semi-batch process at temperatures ranging from 40 to 60ºC and pressures ranging from 10 to 30 MPa, with a carbon dioxide (CO2) flow rate of 26.81 g/min. The oil obtained from wheat bran at different extraction conditions was quantitatively measured to investigate the solubility of oil in SC-CO2. The solubility of wheat bran oil was found to be enhanced in high temperature and pressure. The composition of fatty acids in wheat bran oil was measured by gas chromatography (GC). Linoleic, palmitic, oleic and γ-linolenic acid were the major fatty acids of wheat bran oil. Tocopherol contents in oil were analyzed by high performance liquid chromatography (HPLC). The highest amount of phenolics and tocopherols (α and β) were found at temperature of 60ºC and pressure of 30 MPa.

Keywords: Supercritical carbon dioxide, Tocopherols, Totalphenolic content, Wheat bran oil

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