Search results for: Emotional surface action strategy
Commenced in January 2007
Frequency: Monthly
Edition: International
Paper Count: 3746

Search results for: Emotional surface action strategy

896 Power Factor Correction Based on High Switching Frequency Resonant Power Converter

Authors: B. Sathyanandhi, P. M. Balasubramaniam

Abstract:

This paper presents Buck-Boost converter topology to maintain the input power factor by using the power factor stage control and regulation stage control. Suppose, if we are using the RL load the power factor will be reduced due to the presence of total harmonic distortion in the current wave. To improve the power factor the current waveform should follow the fundamental component of the voltage waveform. These can be achieved by using the high -frequency power converter. Based on the resonant circuit the converter is able to perform the function of Buck, Boost, and buck-boost converter. Here ,we have used Buck-Boost converter, because, the buck-boost converter has more advantages than the boost converter. Here the switching action of the power converter can  take place by using the external zero comparator PFC stage control. The power converter consisting of the resonant  circuit which is used to control the output voltage gain of the converter. The power converter is operated at a very high switching frequency in the range of 400KHz in order to overcome the switching losses of the power converter. Due to  presence of high switching frequency, the power factor will improve. Therefore, the total harmonics distortion present in the current waveform has also reduced. These results has generated in the form of simulation by using MATLAB/SIMULINK software.  Similar to the Buck and Boost converters, the operation of the Buck-Boost has best understood, in terms of the inductor's "reluctance" for allowing rapid change in current, which also reduces the Total Harmonic Distortion (THD) in the input current waveform, which can improve the input Power factor, based on the type of load used.

Keywords: Buck-boost converter, High switching frequency, Power factor correction, power factor correction stage Regulation stage, Total harmonic distortion (THD).

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895 Through the Lens of Forced Displacement: Refugee Women's Rights as Human Rights

Authors: Pearl K. Atuhaire, Sylvia Kaye

Abstract:

While the need for equal access to civil, political as well as economic, social and cultural rights is clear under the international law, the adoption of the Convention on the Elimination of all forms of Discrimination against women in 1979 made this even clearer. Despite this positive progress, the abuse of refugee women's rights is one of the basic underlying root causes of their marginalisation and violence in their countries of asylum. This paper presents a critical review on the development of refugee women's rights at the international levels and national levels. It provides an array of scholarly literature on this issue and examines the measures taken by the international community to curb the problem of violence against women in their various provisions through the instruments set. It is cognizant of the fact that even if conflict affects both refugee women and men, the effects on women refugees are deep-reaching, due to the cultural strongholds they face. An important aspect of this paper is that it is conceptualised against the fact that refugee women face the problem of sexual and gender based first as refugees and second as women, yet, their rights are stumbled upon. Often times they have been rendered "worthless victims" who are only in need of humanitarian assistance than active participants committed to change their plight through their participation in political, economic and social participation in their societies. Scholars have taken notice of the fact that women's rights in refugee settings have been marginalized and call for a need to incorporate their perspectives in the planning and management of refugee settings in which they live. Underpinning this discussion is feminism theory which gives a clear understanding of the root cause of refugee women's problems. Finally, this paper suggests that these policies should be translated into action at local, national international and regional levels to ensure sustainable peace.

Keywords: Feminism theory, human rights, refugee women, sexual and gender based violence.

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894 Work Function Engineering of Functionally Graded ZnO+Ga2O3 Thin Film for Solar Cell and Organic Light Emitting Diodes Applications

Authors: Yong-Taeg Oh, Won Song, Seok-Eui Choi, Bo-Ra Koo, Dong-Chan Shin

Abstract:

ZnO+Ga2O3 functionally graded thin films (FGTFs) were examined for their potential use as Solar cell and organic light emitting diodes (OLEDs). FGTF transparent conducting oxides (TCO) were fabricated by combinatorial RF magnetron sputtering. The composition gradient was controlled up to 10% by changing the plasma power of the two sputter guns. A Ga2O3+ZnO graded region was placed on the top layer of ZnO. The FGTFs showed up to 80% transmittance. Their surface resistances were reduced to < 10% by increasing the Ga2O3: pure ZnO ratio in the TCO. The FGTFs- work functions could be controlled within a range of 0.18 eV. The controlled work function is a very promising technology because it reduces the contact resistance between the anode and Hall transport layers of OLED and solar cell devices.

Keywords: Work Function, TCO, Functionally Graded Thin Films, Resistance, Transmittance.

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893 Characterization of Candlenut Shells and Its Application to Remove Oil and Fine Solids of Produced Water in Nutshell Filters of Water Cleaning Plant

Authors: Annur Suhadi, Haris B. Harahap, Zaim Arrosyidi, Epan, Darmapala

Abstract:

Oilfields under waterflood often face the problem of plugging injectors either by internal filtration or external filter cake built up inside pore throats. The content of suspended solids shall be reduced to required level of filtration since corrective action of plugging is costly expensive. The performance of nutshell filters, where filtration takes place, is good using pecan and walnut shells. Candlenut shells were used instead of pecan and walnut shells since they were abundant in Indonesia, Malaysia, and East Africa. Physical and chemical properties of walnut, pecan, and candlenut shells were tested and the results were compared. Testing, using full-scale nutshell filters, was conducted to determine the oil content, turbidity, and suspended solid removal, which was based on designed flux rate. The performance of candlenut shells, which were deeply bedded in nutshell filters for filtration process, was monitored. Cleaned water outgoing nutshell filters had total suspended solids of 17 ppm, while oil content could be reduced to 15.1 ppm. Turbidity, using candlenut shells, was below the specification for injection water, which was less than 10 Nephelometric Turbidity Unit (NTU). Turbidity of water, outgoing nutshell filter, was ranged from 1.7-5.0 NTU at various dates of operation. Walnut, pecan, and candlenut shells had moisture content of 8.98 wt%, 10.95 wt%, and 9.95 wt%, respectively. The porosity of walnut, pecan, and candlenut shells was significantly affected by moisture content. Candlenut shells had property of toluene solubility of 7.68 wt%, which was much higher than walnut shells, reflecting more crude oil adsorption. The hardness of candlenut shells was 2.5-3 Mohs, which was close to walnut shells’ hardness. It was advantage to guarantee the cleaning filter cake by fluidization process during backwashing.

Keywords: Candlenut shells, walnut shells, pecan shells, nutshell filter, filtration.

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892 Equilibrium, Kinetics and Thermodynamic Studies for Adsorption of Hg (II) on Palm Shell Powder

Authors: Shilpi Kushwaha, Suparna Sodaye, P. Padmaja

Abstract:

Palm shell obtained from coastal part of southern India was studied for the removal for the adsorption of Hg (II) ions. Batch adsorption experiments were carried out as a function of pH, concentration of Hg (II) ions, time, temperature and adsorbent dose. Maximum removal was seen in the range pH 4.0- pH 7.0. The palm shell powder used as adsorbent was characterized for its surface area, SEM, PXRD, FTIR, ion exchange capacity, moisture content, and bulk density, soluble content in water and acid and pH. The experimental results were analyzed using Langmuir I, II, III, IV and Freundlich adsorption isotherms. The batch sorption kinetics was studied for the first order reversible reaction, pseudo first order; pseudo second order reaction and the intra-particle diffusion reaction. The biomass was successfully used for removal Hg (II) from synthetic and industrial effluents and the technique appears industrially applicable and viable.

Keywords: Biosorbent, mercury removal, borassus flabellifer, isotherms, kinetics, palm shell.

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891 Bi-axial Stress Effects on Barkhausen-Noise

Authors: G. Balogh, I. A. Szabó, P. Z. Kovács

Abstract:

Mechanical stress has a strong effect on the magnitude of the Barkhausen-noise in structural steels. Because the measurements are performed at the surface of the material, for a sample sheet, the full effect can be described by a biaxial stress field. The measured Barkhausen-noise is dependent on the orientation of the exciting magnetic field relative to the axis of the stress tensor. The sample inhomogenities including the residual stress also modifies the angular dependence of the measured Barkhausen-noise. We have developed a laboratory device with a cross like specimen for bi-axial bending. The measuring head allowed performing excitations in two orthogonal directions. We could excite the two directions independently or simultaneously with different amplitudes. The simultaneous excitation of the two coils could be performed in phase or with a 90 degree phase shift. In principle this allows to measure the Barkhausen-noise at an arbitrary direction without moving the head, or to measure the Barkhausen-noise induced by a rotating magnetic field if a linear superposition of the two fields can be assumed.

Keywords: Barkhausen-noise, Bi-axial stress, Stress dependency, Stress measuring.

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890 Robust Sensorless Speed Control of Induction Motor with DTFC and Fuzzy Speed Regulator

Authors: Jagadish H. Pujar, S. F. Kodad

Abstract:

Recent developments in Soft computing techniques, power electronic switches and low-cost computational hardware have made it possible to design and implement sophisticated control strategies for sensorless speed control of AC motor drives. Such an attempt has been made in this work, for Sensorless Speed Control of Induction Motor (IM) by means of Direct Torque Fuzzy Control (DTFC), PI-type fuzzy speed regulator and MRAS speed estimator strategy, which is absolutely nonlinear in its nature. Direct torque control is known to produce quick and robust response in AC drive system. However, during steady state, torque, flux and current ripple occurs. So, the performance of conventional DTC with PI speed regulator can be improved by implementing fuzzy logic techniques. Certain important issues in design including the space vector modulated (SVM) 3-Ф voltage source inverter, DTFC design, generation of reference torque using PI-type fuzzy speed regulator and sensor less speed estimator have been resolved. The proposed scheme is validated through extensive numerical simulations on MATLAB. The simulated results indicate the sensor less speed control of IM with DTFC and PI-type fuzzy speed regulator provides satisfactory high dynamic and static performance compare to conventional DTC with PI speed regulator.

Keywords: Sensor-less Speed Estimator, Fuzzy Logic Control(FLC), SVM, DTC, DTFC, IM, fuzzy speed regulator.

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889 Landfill Design for Reclamation of Şırnak Coal Mine Dumps: Shalefill Stability and Risk Assessment

Authors: Yıldırım I. Tosun, Halim Cevizci, Hakan Ceylan

Abstract:

By GEO5 FEM program with four rockfill slope modeling and stability analysis was performed for S1, S2, S3 and S4 slopes where landslides of the shalefills were limited. Effective angle of internal friction (φ'°) 17°-22.5°, the effective cohesion (c') from 0.5 to 1.8 kPa, saturated unit weight 1.78-2.43 g/cm3, natural unit weight 1.9-2.35 g/cm3, dry unit weight 1.97-2.40 g/cm3, the permeability coefficient of 1x10-4 - 6.5x10-4 cm/s. In cross-sections of the slope, GEO 5 FEM program possible critical surface tension was examined. Rockfill dump design was made to prevent sliding slopes. Bulk material designated geotechnical properties using also GEO5 programs FEM and stability program via a safety factor determined and calculated according to the values S3 and S4 No. slopes are stable S1 and S2 No. slopes were close to stable state that has been found to be risk. GEO5 programs with limestone rock fill dump through FEM program was found to exhibit stability.

Keywords: Slope stability, GEO5, rockfills, rock stability.

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888 Titanium-Aluminum Oxide Coating on Aluminized Steel

Authors: Fuyan Sun, Guang Wang, Xueyuan Nie

Abstract:

In this study, a plasma electrolytic oxidation (PEO) process was used to form titanium-aluminum oxide coating on aluminized steel. The present work was mainly to study the effects of treatment time of PEO process on properties of the titanium coating. A potentiodynamic polarization corrosion test was employed to investigate the corrosion resistance of the coating. The friction coefficient and wear resistance of the coating were studied by using pin-on-disc test. The thermal transfer behaviors of uncoated and PEO-coated aluminized steels were also studied. It could be seen that treatment time of PEO process significantly influenced the properties of the titanium oxide coating. Samples with a longer treatment time had a better performance for corrosion and wear protection. This paper demonstrated different treatment time could alter the surface behavior of the coating material.

Keywords: Corrosion, plasma electrolytic oxidation, thermal property, titanium-aluminum oxide.

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887 Image Analysis of Fine Structures of Supercavitation in the Symmetric Wake of a Cylinder

Authors: Y. Obikane , M.Kaneko, K.Kakioka, K.Ogura

Abstract:

The fine structure of supercavitation in the wake of a symmetrical cylinder is studied with high-speed video cameras. The flow is observed in a cavitation tunnel at the speed of 8m/sec when the sidewall and the wake are partially filled with the massive cavitation bubbles. The present experiment observed that a two-dimensional ripple wave with a wave length of 0.3mm is propagated in a downstream direction, and then abruptly increases to a thicker three-dimensional layer. IR-photography recorded that the wakes originated from the horseshoe vortexes alongside the cylinder. The wake was developed to inside the dead water zone, which absorbed the bubbly wake propelled from the separated vortices at the center of the cylinder. A remote sensing classification technique (maximum most likelihood) determined that the surface porosity was 0.2, and the mean speed in the mixed wake was 7m/sec. To confirm the existence of two-dimensional wave motions in the interface, the experiments were conducted at a very low frequency, and showed similar gravity waves in both the upper and lower interfaces.

Keywords: Supercavitation, density gradient correlation

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886 Active Surface Tracking Algorithm for All-Fiber Common-Path Fourier-Domain Optical Coherence Tomography

Authors: Bang Young Kim, Sang Hoon Park, Chul Gyu Song

Abstract:

A conventional optical coherence tomography (OCT) system has limited imaging depth, which is 1-2 mm, and suffers unwanted noise such as speckle noise. The motorized-stage-based OCT system, using a common-path Fourier-domain optical coherence tomography (CP-FD-OCT) configuration, provides enhanced imaging depth and less noise so that we can overcome these limitations. Using this OCT systems, OCT images were obtained from an onion, and their subsurface structure was observed. As a result, the images obtained using the developed motorized-stage-based system showed enhanced imaging depth than the conventional system, since it is real-time accurate depth tracking. Consequently, the developed CP-FD-OCT systems and algorithms have good potential for the further development of endoscopic OCT for microsurgery.

Keywords: Common-path OCT, FD-OCT, OCT, Tracking algorithm.

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885 A Comparison of Dilute Sulfuric and Phosphoric Acid Pretreatments in Biofuel Production from Corncobs

Authors: Jirakarn Nantapipat, Apanee Luengnaruemitchai, Sujitra Wongkasemjit

Abstract:

Biofuels, like biobutanol, have been recognized for being renewable and sustainable fuels which can be produced from lignocellulosic biomass. To convert lignocellulosic biomass to biofuel, pretreatment process is an important step to remove hemicelluloses and lignin to improve enzymatic hydrolysis. Dilute acid pretreatment has been successful developed for pretreatment of corncobs and the optimum conditions of dilute sulfuric and phosphoric acid pretreatment were obtained at 120 °C for 5 min with 15:1 liquid to solid ratio and 140 °C for 10 min with 10:1 liquid to solid ratio, respectively. The result shows that both of acid pretreatments gave the content of total sugar approximately 34–35 g/l. In case of inhibitor content (furfural), phosphoric acid pretreatment gives higher than sulfuric acid pretreatment. Characterizations of corncobs after pretreatment indicate that both of acid pretreatments can improve enzymatic accessibility and the better results present in corncobs pretreated with sulfuric acid in term of surface area, crystallinity, and composition analysis.

Keywords: Corncobs, Pretreatment, Sulfuric acid, Phosphoric acid.

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884 Assessment of Health and Safety Item on Construction Sites in Ondo State

Authors: Ikumapayi Catherine Mayowa

Abstract:

The well been of human beings on construction site is very important, many man power had been lost through accidents which kills or make workers physically unfit to carry out construction activities, these in turn have multiple effects on the whole economy. Thus it is necessary to put all safety items and regulations in place before construction activities can commence. This study was carried out in Ondo state of Nigeria to known and analyse the state of health and safety of construction workers in the state. The study was done using first hand observation method, 50 construction project sites were visited in 10 major towns of Ondo state, questionnaires were distributed and the results were analysed. The result show that construction workers are being exposed to a lot of construction site hazards due to lack of inadequate safety programmes and nonprovision of appropriate safety materials for workers on site. From the data gotten for each site visited and the statistical analysis, it can be concluded that occurrence of accident on construction sites depends significantly on the available safety facilities on the sites. The result of the regression statistics show that the level of significant of the dependence of occurrence of accident on the availability of safety items on site is 0.0362 which is less than 0.05 maximum significant level required. Therefore a vital way of sustaining our building strategy is by given a detail attention to provision of adequate health and safety items on construction sites which will reduce the occurrence of accident, loss of man power and death of skilled workers among others.

Keywords: Construction sites, health, safety, welfare.

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883 Lattice Boltzmann Method for Turbulent Heat Transfer in Wavy Channel Flows

Authors: H.Y. Lai, S. C. Chang, W. L. Chen

Abstract:

The hydrodynamic and thermal lattice Boltzmann methods are applied to investigate the turbulent convective heat transfer in the wavy channel flows. In this study, the turbulent phenomena are modeling by large-eddy simulations with the Smagorinsky model. As a benchmark, the laminar and turbulent backward-facing step flows are simulated first. The results give good agreement with other numerical and experimental data. For wavy channel flows, the distribution of Nusselt number and the skin-friction coefficients are calculated to evaluate the heat transfer effect and the drag force. It indicates that the vortices at the trough would affect the magnitude of drag and weaken the heat convection effects on the wavy surface. In turbulent cases, if the amplitude of the wavy boundary is large enough, the secondary vortices would be generated at troughs and contribute to the heat convection. Finally, the effects of different Re on the turbulent transport phenomena are discussed.

Keywords: Heat transfer, lattice Boltzmann method, turbulence, wavy channel.

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882 On the Allopatry of National College Entrance Exam in China: The Root, Policy and Strategy

Authors: Shi Zhang

Abstract:

This paper aims to introduce the allopatry of national college entrance examination which allow migrant students enter senior high schools and take college entrance exam where they live, identifies the reasons affect the implementation of this policy in the Chinese context. Most of China’s provinces and municipalities recently have announced new policies regarding national college entrance exams for non-local students. The paper conducts SWOT analysis reveals the opportunities, strength, weakness and challenges of the scheme, so as to discuss the implementation strategies from the perspectives of idea and institution. The research findings imply that the government should take a more positive attitude toward relaxing the allopatry of NCEE policy restrictions, and promote the reform household registration policy and NCEE policy with synchronous operations. Higher education institutions should explore the diversification of enrollment model; the government should issue the authority of universities and colleges to select elite migrant students beyond the restrictions of NCEE. To suit reform policies to local conditions, the big cities such as Beijing, Shanghai and Guangzhou should publish related compensate measures for children of migrant workers access to higher vocational colleges with tuition fee waivered. 

Keywords: College entrance examination, higher education, education policy, education equality.

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881 The Social Area Disclosure to Reduce Conflicts between Community and the State: A Case of Mahakan Fortress, Bangkok

Authors: Saowapa Phaithayawat

Abstract:

The purposes of this study are 1) to study the over 20-year attempt of Mahakan fort community to negotiate with Bangkok Metropolitan Administration (BMA) to remain in their residential area belonging to the state, and 2) to apply the new social and cultural dimension between the state and the community as an alternative for local participation in keeping their residential area. This is a qualitative research, and the findings reveal that the community claimed their ancestors’ right as owners of this piece of land for over 200 years. The community, therefore, requested to take part in the preservation of land, culture and local intellect and the area management in terms of being a learning resource on the cultural road in Rattanakosin Island. However, BMA imposed the law concerning the community area relocation in Rattanakosin Island. The result of law enforcement led to the failure of the area relocation, and the hard hit on physical structure of the area including the overall deterioration of the cultural road renovated in the year 1982, the 200 years’ celebration of Bangkok. The enforcement of law by the state required the move of the community, and the landscape improvement based on the capital city plan. However, this enforcement resulted in the unending conflicts between the community and the state, and the solution of this problem was unclear. At the same time the community has spent a long time opposing the state’s action, and preparing themselves by administrating the community behind Mahakan fortress with community administrative committee under the suggestion of external organization by registering all community members, providing funds for community administration. At the meantime the state lacked the continuation of the enforcement due to political problem and BMA’s administration problem. It is, therefore, suggested that an alternative solution to this problem lie at the negotiation between the state and the community with the purpose of the collaboration between the two to develop the area under the protective law of each side.

Keywords: Pom-Mahakan Community, The Reduction of Conflicts, The Social Area Disclosure.

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880 In vitro and in vivo Anticancer Activity of Nanosize Zinc Oxide Composites of Doxorubicin

Authors: E. R. Arakelova, S. G. Grigoryan, F. G. Arsenyan, N. S. Babayan, R. M. Grigoryan, N. K. Sarkisyan

Abstract:

The nanotechnology offers some exciting possibilities in cancer treatment, including the possibility of destroying tumors with minimal damage to healthy tissue and organs by targeted drug delivery systems. Considerable achievements in investigations aimed at the use of ZnO nanoparticles and nanocontainers in diagnostics and antitumor therapy were described. However, there are substantial obstacles to the purposes to be achieved by the use of zinc oxide nanosize materials in antitumor therapy. Among the serious problems are the techniques of obtaining ZnO nanosize materials. The article presents a new vector delivery system for the known antitumor drug, doxorubicin in the form of polymeric (PEO, starch-NaCMC) hydrogels, in which nanosize ZnO film of a certain thickness are deposited directly on the drug surface on glass substrate by DC-magnetron sputtering of a zinc target. Anticancer activity in vitro and in vivo of those nanosize zinc oxide composites is shown.

Keywords: Anticancer activity, cancer specificity, doxorubicin, zinc oxide.

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879 Performance Evaluation of Karanja Oil Based Biodiesel Engine Using Modified Genetic Algorithm

Authors: G. Bhushan, S. Dhingra, K. K. Dubey

Abstract:

This paper presents the evaluation of performance (BSFC and BTE), combustion (Pmax) and emission (CO, NOx, HC and smoke opacity) parameters of karanja biodiesel in a single cylinder, four stroke, direct injection diesel engine by considering significant engine input parameters (blending ratio, compression ratio and load torque). Multi-objective optimization of performance, combustion and emission parameters is also carried out in a karanja biodiesel engine using hybrid RSM-NSGA-II technique. The pareto optimum solutions are predicted by running the hybrid RSM-NSGA-II technique. Each pareto optimal solution is having its own importance. Confirmation tests are also conducted at randomly selected few pareto solutions to check the authenticity of the results.

Keywords: Karanja biodiesel, single cylinder direct injection diesel engine, response surface methodology, central composite rotatable design, genetic algorithm.

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878 Magnesium Alloy: A Biomaterial for Development of Degradation Rate Controllable Esophageal Stent

Authors: Li Hong Chen, Wei Zhou, Chu Sing Lim, Eng Kiong Teo, Ngai Moh Law

Abstract:

Magnesium alloy has been widely investigated as biodegradable cardiovascular stent and bone implant. Its application for biodegradable esophageal stenting remains unexplored. This paper reports the biodegradation behaviors of AZ31 magnesium alloy in artificial saliva and various types of beverage in vitro. Results show that the magnesium ion release rate of AZ31 in artificial saliva for a stent (2cm diameter, 10cm length at 50% stent surface coverage) is 43 times lower than the daily allowance of human body magnesium intakes. The degradation rates of AZ31 in different beverages could also be significantly different. These results suggest that the esophagus in nature is a less aggressive chemical environment for degradation of magnesium alloys. The significant difference in degradation rates of AZ31 in different beverages opens new opportunities for development of degradation controllable esophageal stent through customizing ingested beverages.

Keywords: Biodegradable esophageal stent, beverages, magnesium alloy, saliva.

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877 Effect of the Support Shape on Fischer-Tropsch Cobalt Catalyst Performance

Authors: Jian Huang, Weixin Qian, Hongfang Ma, Haitao Zhang, Weiyong Ying

Abstract:

Cobalt catalysts were supported on extruded silica carrier and different-type (SiO2, γ-Al2O3) commercial supports with different shapes and sizes to produce heavy hydrocarbons for Fischer-Tropsch synthesis. The catalysts were characterized by N2 physisorption and H2-TPR. The catalytic performance of the catalysts was tested in a fixed bed reactor. The results of Fischer-Tropsch synthesis performance showed that the cobalt catalyst supported on spherical silica supports displayed a higher activity and a higher selectivity to C5+ products, due to the fact that the active components were only distributed in the surface layer of spherical carrier, and the influence of gas diffusion restriction on catalytic performance was weakened. Therefore, it can be concluded that the eggshell cobalt catalyst was superior to precious metals modified catalysts in the synthesis of heavy hydrocarbons.

Keywords: Fischer-Tropsch synthesis, cobalt catalyst, support shape, heavy hydrocarbons.

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876 Texture Based Weed Detection Using Multi Resolution Combined Statistical and Spatial Frequency (MRCSF)

Authors: R.S.Sabeenian, V.Palanisamy

Abstract:

Texture classification is a trendy and a catchy technology in the field of texture analysis. Textures, the repeated patterns, have different frequency components along different orientations. Our work is based on Texture Classification and its applications. It finds its applications in various fields like Medical Image Classification, Computer Vision, Remote Sensing, Agricultural Field, and Textile Industry. Weed control has a major effect on agriculture. A large amount of herbicide has been used for controlling weeds in agriculture fields, lawns, golf courses, sport fields, etc. Random spraying of herbicides does not meet the exact requirement of the field. Certain areas in field have more weed patches than estimated. So, we need a visual system that can discriminate weeds from the field image which will reduce or even eliminate the amount of herbicide used. This would allow farmers to not use any herbicides or only apply them where they are needed. A machine vision precision automated weed control system could reduce the usage of chemicals in crop fields. In this paper, an intelligent system for automatic weeding strategy Multi Resolution Combined Statistical & spatial Frequency is used to discriminate the weeds from the crops and to classify them as narrow, little and broad weeds.

Keywords: crop weed discrimination, MRCSF, MRFM, Weeddetection, Spatial Frequency.

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875 Removal of Ciprofloxazin and Carbamazepine by Adsorption on Functionalized Mesoporous Silicates

Authors: Patiparn Punyapalakul, Thitikamon Sitthisorn

Abstract:

Ciprofloxacin (CIP) and Carbamazepine (CBZ), nonbiodegradable pharmaceutical residues, were become emerging pollutants in several aquatic environments. The objectives of this research were to study the possibility to recover these pharmaceuticals residues from pharmaceutical wastewater by increasing the selective adsorption on synthesized functionalized porous silicate, comparing with powdered activated carbon (PAC). Hexagonal mesoporous silicate (HMS), functionalized HMSs (3- aminopropyltriethoxy, 3- mercaptopropyltrimethoxy and noctyldimethyl) were synthesized and characterized physico-chemical characteristics. Obtained adsorption kinetics and isotherms showed that 3-mercaptopropyltrimethoxy functional groups grafted on HMS provided highest CIP and CBZ adsorption capacities; however, it was still lower than that of PAC. The kinetic results were compatible with pseudo-second order. The hydrophobicity and hydrogen bonding might play a key role on the adsorption. Furthermore, the capacities were affected by varying pH values due to the strength of hydrogen bonding between targeted compounds and adsorbents. Electrostatic interaction might not affect the adsorption capacities.

Keywords: Adsorption, Carbamazepine, Ciprofloxazin, Mesoporous Silicates, Surface functional groups

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874 Effect of Oxygen on Biochar Yield and Properties

Authors: Ramlan Zailani, Halim Ghafar, Mohamad Sofian So'aib

Abstract:

Air infiltration in mass scale industrial applications of bio char production is inevitable. The presence of oxygen during the carbonization process is detrimental to the production of biochar yield and properties. The experiment was carried out on several wood species in a fixed-bed pyrolyser under various fractions of oxygen ranging from 0% to 11% by varying nitrogen and oxygen composition in the pyrolysing gas mixtures at desired compositions. The bed temperature and holding time were also varied. Process optimization was carried out by Response Surface Methodology (RSM) by employing Central Composite Design (CCD) using Design Expert 6.0 Software. The effect of oxygen ratio and holding time on biochar yield within the range studied were statistically significant. From the analysis result, optimum condition of 15.2% biochar yield of mangrove wood was predicted at pyrolysis temperature of 403 oC, oxygen percentage of 2.3% and holding time of two hours. This prediction agreed well with the experiment finding of 15.1% biochar yield.

Keywords: Mangrove wood, slow pyrolysis, oxygen infiltration.

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873 Molecular Dynamics Simulation of Annular Flow Boiling in a Microchannel with 70000 Atoms

Authors: D.Toghraie, A.R.Azimian

Abstract:

Molecular dynamics simulation of annular flow boiling in a nanochannel with 70000 particles is numerically investigated. In this research, an annular flow model is developed to predict the superheated flow boiling heat transfer characteristics in a nanochannel. To characterize the forced annular boiling flow in a nanochannel, an external driving force F ext ranging from 1to12PN (PN= Pico Newton) is applied along the flow direction to inlet fluid particles during the simulation. Based on an annular flow model analysis, it is found that saturation condition and superheat degree have great influences on the liquid-vapor interface. Also, the results show that due to the relatively strong influence of surface tension in small channel, the interface between the liquid film and vapor core is fairly smooth, and the mean velocity along the stream-wise direction does not change anymore.

Keywords: Lennard-Jones Potential, Molecular DynamicsSimulation, Periodic Boundary Conditions (PBC), Non-EquilibriumMolecular Dynamics (NEMD), Annular Flow Boiling

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872 Deactivation of Cu - Cr/γ-alumina Catalysts for Combustion of Exhaust Gases

Authors: Krasimir Ivanov, Dimitar Dimitrov, Boyan Boyanov

Abstract:

The paper relates to a catalyst, comprising copperchromium spinel, coated on carrier γ-Al2O3. The effect of preparation conditions on the active component composition and activity behavior of the catalysts is discussed. It was found that the activity of carbon monoxide, DME, formaldehyde and methanol oxidation reaches a maximum at an active component content of 20 – 30 wt. %. Temperature calcination at 500oC seems to be optimal for the γ– alumina supported CuO-Cr2O3 catalysts for CO, DME, formaldehyde and methanol oxidation. A three months industrial experiment was carried out to elucidate the changes in the catalyst composition during industrial exploitation of the catalyst and the main reasons for catalyst deactivation. It was concluded that the CuO–Cr2O3/γ–alumina supported catalysts have enhanced activity toward CO, DME, formaldehyde and methanol oxidation and that these catalysts are suitable for industrial application. The main reason for catalyst deactivation seems to be the deposition of iron and molybdenum, coming from the main reactor, on the active component surface.

Keywords: catalyst deactivation, CuO-Cr2O3 catalysts, deep oxidation.

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871 Output Regulation of Perturbed Nonlinear Systems by Nested Sliding Mode Control

Authors: Aras Adhami Mirhoseini, Mohammad J. Yazdanpanah

Abstract:

In this paper, we consider nested sliding mode control of SISO nonlinear systems, perturbed by bounded matched and unmatched uncertainties. The systems are assumed to be in strict-feedback form. A step wise procedure is introduced to obtain the controller. In each step, a continuous sliding mode controller is designed as virtual control law. Then the next step sliding surface is defined by using this virtual controller. These sliding surfaces are selected as nonlinear static functions of the system states. Finally in the last step, smooth static state feedback control law is determined such that the output reaches the desired set-point while the system is forced arbitrary close to the intersection of sliding surfaces and the states remain bounded.

Keywords: Sliding mode control, Strict-feedback form, Unmatched uncertainty, output regulation.

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870 Competitive Advantage Challenges Affecting the Apparel Manufacturing Industry of South Africa (AMISA): Application of Porter’s Factor Conditions

Authors: S. Mbatha, A. Mastamet-Mason

Abstract:

This paper applied factor conditions from Porter’s Diamond Model (1990) to understand the various challenges facing the AMISA. Factor conditions highlighted in Porter’s model are grouped into two groups namely, basic and advance factors. Two AMISA associations representing over 10 000 employees were interviewed. The largest Clothing, Textiles and Leather (CTL) apparel retail group was also interviewed with a government department implementing the industrialization policy were interviewed. The paper points out that AMISA have basic factor conditions necessary for competitive advantage in the apparel industries. However advance factor creation has proven to be a challenge for AMISA, Higher Education Institutions (HEIs) and government. Poor infrastructural maintenance has contributed to high manufacturing costs and poor quick response technologies. The use of Porter’s Factor Conditions as a tool to analyze the sector’s competitive advantage challenges and opportunities has increased knowledge regarding factors that limit the AMISA’s competitiveness. It is therefore argued that other studies on Porter’s Diamond model factors like Demand conditions, Firm strategy, structure and rivalry and Related and supporting industries can be used to analyze the situation of the AMISA for the purposes of improving competitive advantage.

Keywords: Compliance rule, apparel manufacturing industry, factor conditions, advance skills.

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869 The Concentration Effects for the Adsorption Behavior of Heptyl Viologen Cation Radicals on Indium-Tin-Oxide Electrode Surfaces

Authors: Yusuke Ayato, Takashi Itahashi, Akiko Takatsu, Kenji Kato, Naoki Matsuda

Abstract:

In situ observation of absorption spectral change of heptil viologen cation radical (HV+.) was performed by slab optical waveguide (SOWG) spectroscopy utilizing indium-tin-oxide (ITO) electrodes. Synchronizing with electrochemical techniques, we observed the adsorption process of HV+.on the ITO electrode. In this study, we carried out the ITO-SOWG observations using KBr aqueous solution containing different concentration of HV to investigate the concentration dependent spectral change. A few specific absorption bands, which indicated HV+.existed as both monomer and dimer on ITO electrode surface with a monolayer or a few layers deposition, were observed in UV-visible region. The change in the peak position of the absorption spectra from adsorption species of HV+. were correlated with the concentration of HV as well as the electrode potential.

Keywords: absorption phenomena, heptil viologen, indium-tin-oxide (ITO) electrode, in situ, slab optical waveguide(SOWG) spectroscopy,

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868 A Multi-Radio Multi-Channel Unification Power Control for Wireless Mesh Networks

Authors: T. O. Olwal, K. Djouani, B. J. van Wyk, Y. Hamam, P. Siarry

Abstract:

Multi-Radio Multi-Channel Wireless Mesh Networks (MRMC-WMNs) operate at the backbone to access and route high volumes of traffic simultaneously. Such roles demand high network capacity, and long “online" time at the expense of accelerated transmission energy depletion and poor connectivity. This is the problem of transmission power control. Numerous power control methods for wireless networks are in literature. However, contributions towards MRMC configurations still face many challenges worth considering. In this paper, an energy-efficient power selection protocol called PMMUP is suggested at the Link-Layer. This protocol first divides the MRMC-WMN into a set of unified channel graphs (UCGs). A UCG consists of multiple radios interconnected to each other via a common wireless channel. In each UCG, a stochastic linear quadratic cost function is formulated. Each user minimizes this cost function consisting of trade-off between the size of unification states and the control action. Unification state variables come from independent UCGs and higher layers of the protocol stack. The PMMUP coordinates power optimizations at the network interface cards (NICs) of wireless mesh routers. The proposed PMMUP based algorithm converges fast analytically with a linear rate. Performance evaluations through simulations confirm the efficacy of the proposed dynamic power control.

Keywords: Effective band inference based power control algorithm (EBIA), Power Selection MRMC Unification Protocol (PMMUP), MRMC State unification Variable Prediction (MRSUP), Wireless Mesh Networks (WMNs).

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867 The Temperature Effects on the Microstructure and Profile in Laser Cladding

Authors: P. C. Chiu, Jehnming Lin

Abstract:

In this study, a 50-W CO2 laser was used for the clad of 304L powders on the stainless steel substrate with a temperature sensor and image monitoring system. The laser power and cladding speed and focal position were modified to achieve the requirement of the workpiece flatness and mechanical properties. The numerical calculation is based on ANSYS to analyze the temperature change of the moving heat source at different surface positions when coating the workpiece, and the effect of the process parameters on the bath size was discussed. The temperature of stainless steel powder in the nozzle outlet reacting with the laser was simulated as a process parameter. In the experiment, the difference of the thermal conductivity in three-dimensional space is compared with single-layer cladding and multi-layer cladding. The heat dissipation pattern of the single-layer cladding is the steel plate and the multi-layer coating is the workpiece itself. The relationship between the multi-clad temperature and the profile was analyzed by the temperature signal from an IR pyrometer.

Keywords: Laser cladding, temperature, profile, microstructure.

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