Search results for: impact factor
Commenced in January 2007
Frequency: Monthly
Edition: International
Paper Count: 3640

Search results for: impact factor

3370 Investigating Daylight Quality in Malaysian Government Office Buildings Through Daylight Factor and Surface Luminance

Authors: Mohd Zin Kandar, Mohd Sabere Sulaiman, Yong Razidah Rashid, Dilshan Remaz Ossen, Aminatuzuhariah MAbdullah, Lim Yaik Wah, Mansour Nikpour

Abstract:

In recent years, there has been an increasing interest in using daylight to save energy in buildings. In tropical regions, daylighting is always an energy saver. On the other hand, daylight provides visual comfort. According to standards, it shows that many criteria should be taken into consideration in order to have daylight utilization and visual comfort. The current standard in Malaysia, MS 1525 does not provide sufficient guideline. Hence, more research is needed on daylight performance. If architects do not consider daylight design, it not only causes inconvenience in working spaces but also causes more energy consumption as well as environmental pollution. This research had surveyed daylight performance in 5 selected office buildings from different area of Malaysian through experimental method. Several parameters of daylight quality such as daylight factor, surface luminance and surface luminance ratio were measured in different rooms in each building. The result of this research demonstrated that most of the buildings were not designed for daylight utilization. Therefore, it is very important that architects follow the daylight design recommendation to reduce consumption of electric power for artificial lighting while the sufficient quality of daylight is available.

Keywords: Daylight factor, Field measurement, Daylighting quality, Tropical

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3369 Potential Effects of Human Bone Marrow Non- Mesenchymal Mononuclear Cells on Neuronal Differentiation

Authors: Chareerut Phruksaniyom, Khwanthana Grataitong, Permphan Dharmasaroja, Surapol Issaragrisil

Abstract:

Bone marrow-derived stem cells have been widely studied as an alternative source of stem cells. Mesenchymal stem cells (MSCs) were mostly investigated and studies showed MSCs can promote neurogenesis. Little is known about the non-mesenchymal mononuclear cell fraction, which contains both hematopoietic and nonhematopoietic cells, including monocytes and endothelial progenitor cells. This study focused on unfractionated bone marrow mononuclear cells (BMMCs), which remained 72 h after MSCs were adhered to the culture plates. We showed that BMMC-conditioned medium promoted morphological changes of human SH-SY5Y neuroblastoma cells from an epithelial-like phenotype towards a neuron-like phenotype as indicated by an increase in neurite outgrowth, like those observed in retinoic acid (RA)-treated cells. The result could be explained by the effects of trophic factors released from BMMCs, as shown in the RT-PCR results that BMMCs expressed nerve growth factor (NGF), brain-derived neurotrophic factor (BDNF), and ciliary neurotrophic factor (CNTF). Similar results on the cell proliferation rate were also observed between RA-treated cells and cells cultured in BMMC-conditioned medium, suggesting that cells creased proliferating and differentiated into a neuronal phenotype. Using real-time RT-PCR, a significantly increased expression of tyrosine hydroxylase (TH) mRNA in SHSY5Y cells indicated that BMMC-conditioned medium induced catecholaminergic identities in differentiated SH-SY5Y cells.

Keywords: bone marrow, neuronal differentiation, neurite outgrowth, trophic factor, tyrosine hydroxylase

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3368 Electrical Analysis of Corn Oil as an Alternative to Mineral Oil in Power Transformers

Authors: E. Taslak, C. Kocatepe, O. Arıkan, C. F. Kumru

Abstract:

In insulation and cooling of power transformers various liquids are used. Mineral oils have wide availability and low cost. However, they have a poor biodegradability potential and lower fire point in comparison with other insulating liquids. Use of a liquid having high biodegradability is important due to environmental consideration. This paper investigates edible corn oil as an alternative to mineral oil. Various properties of mineral and corn oil like breakdown voltage, dissipation factor, relative dielectric constant, power loss and resistivity were measured according to different standards.

Keywords: Breakdown voltage, corn oil, dissipation factor, mineral oil, power loss, relative dielectric constant, resistivity.

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3367 Risk and Uncertainty in Aviation: A Thorough Analysis of System Vulnerabilities

Authors: C. V. Pietreanu, S. E. Zaharia, C. Dinu

Abstract:

Hazard assessment and risks quantification are key components for estimating the impact of existing regulations. But since regulatory compliance cannot cover all risks in aviation, the authors point out that by studying causal factors and eliminating uncertainty, an accurate analysis can be outlined. The research debuts by making delimitations on notions, as confusion on the terms over time has reflected in less rigorous analysis. Throughout this paper, it will be emphasized the fact that the variation in human performance and organizational factors represent the biggest threat from an operational perspective. Therefore, advanced risk assessment methods analyzed by the authors aim to understand vulnerabilities of the system given by a nonlinear behavior. Ultimately, the mathematical modeling of existing hazards and risks by eliminating uncertainty implies establishing an optimal solution (i.e. risk minimization).

Keywords: Control, human factor, optimization, risk management, uncertainty.

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3366 Determination of the Optimum Size of Building Stone Blocks: Case Study of Delichai Travertine Mine

Authors: Hesam Sedaghat Nejad, Navid Hosseini, Arash Nikvar Hassani

Abstract:

Determination of the optimum block size with high profitability is one of the significant parameters in designation of the building stone mines. The aim of this study was to determine the optimum dimensions of building stone blocks in Delichai travertine mine of Damavand in Tehran province through combining the effective parameters proven in determination of the optimum dimensions in building stones such as the spacing of joints and gaps, extraction tools constraints with the help of modeling by Gemcom software. To this end, following simulation of the topography of the mine, the block model was prepared and then in order to use spacing joints and discontinuities as a limiting factor, the existing joints set was added to the model. Since only one almost horizontal joint set with a slope of 5 degrees was available, this factor was effective only in determining the optimum height of the block, and thus to determine the longitudinal and transverse optimum dimensions of the extracted block, the power of available loader in the mine was considered as the secondary limiting factor. According to the aforementioned factors, the optimal block size in this mine was measured as 3.4×4×7 meter.

Keywords: Building stone, optimum block size, Delichai Travertine Mine, loader power.

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3365 A Content-Based Optimization of Data Stream Television Multiplex

Authors: Jaroslav Polec, Martin Šimek, Michal Martinovič, Elena Šikudová

Abstract:

The television multiplex has reserved capacity and therefore we can use only limited number of videos for propagation of it. Appropriate composition of the multiplex has a major impact on how many videos is spread by multiplex. Therefore in this paper is designed a simple algorithm to optimize capacity utilization multiplex. Significant impact on the number of programs in the multiplex has also the fact from which programs is composed. Content of multiplex can be movies, news, sport, animated stories, documentaries, etc. These types have their own specific characteristics that affect their resulting data stream. In this paper is also done an impact analysis of the composition of the multiplex to use its capacity by video content. 

Keywords: Multiplex, content, group of pictures, frame, capacity.

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3364 Response Surface Based Optimization of Toughness of Hybrid Polyamide 6 Nanocomposites

Authors: E. Hajizadeh, H. Garmabi

Abstract:

Toughening of polyamide 6 (PA6)/ Nanoclay (NC) nanocomposites with styrene-ethylene/butadiene-styrene copolymer (SEBS) using maleated styrene-ethylene/butadiene-styrene copolymer (mSEBS)/ as a compatibilizer were investigated by blending them in a co-rotating twin-screw extruder. Response surface method of experimental design was used for optimizing the material and processing parameters. Effect of four factors, including SEBS, mSEBS and NC contents as material variables and order of mixing as a processing factor, on toughness of hybrid nanocomposites were studied. All the prepared samples showed ductile behavior and low temperature Izod impact toughness of some of the hybrid nanocomposites demonstrated 900% improvement compared to the PA6 matrix while the modulus showed maximum enhancement of 20% compared to the pristine PA6 resin.

Keywords: Hybrid nanocomposites, PA6, SEBS rubber, toughness.

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3363 A Strategy of Direct Power Control for PWM Rectifier Reducing Ripple in Instantaneous Power

Authors: T. Mohammed Chikouche, K. Hartani

Abstract:

In order to solve the instantaneous power ripple and achieve better performance of direct power control (DPC) for a three-phase PWM rectifier, a control method is proposed in this paper. This control method is applied to overcome the instantaneous power ripple, to eliminate line current harmonics and therefore reduce the total harmonic distortion and to improve the power factor. A switching table is based on the analysis on the change of instantaneous active and reactive power, to select the optimum switching state of the three-phase PWM rectifier. The simulation result shows feasibility of this control method.

Keywords: Power quality, direct power control, power ripple, switching table, unity power factor.

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3362 An Adaptive Dynamic Fracture for 3D Fatigue Crack Growth Using X-FEM

Authors: S. Lecheb, A. Nour, A. Chellil, A. Basta, D. Belmiloud, H. Kebi

Abstract:

In recent years, a new numerical method has been developed, the extended finite element method (X-FEM). The objective of this work is to exploit the (X-FEM) for the treatment of the fracture mechanics problems on 3D geometries, where we showed the ability of this method to simulate the fatigue crack growth into two cases: edge and central crack. In the results we compared the six first natural frequencies of mode shapes uncracking with the cracking initiation in the structure, and showed the stress intensity factor (SIF) evolution function as crack size propagation into structure, the analytical validation of (SIF) is presented. For to evidence the aspects of this method, all result is compared between FEA and X-FEM.

Keywords: 3D fatigue crack growth, FEA, natural frequencies, stress intensity factor (SIF), X-FEM.

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3361 Sensitivity Analysis of External-Rotor Permanent Magnet Assisted Synchronous Reluctance Motor

Authors: Hadi Aghazadeh, Seyed Ebrahim Afjei, Alireza Siadatan

Abstract:

In this paper, a proper approach is taken to assess a set of the most effective rotor design parameters for an external-rotor permanent magnet assisted synchronous reluctance motor (PMaSynRM) and therefore to tackle the design complexity of the rotor structure. There are different advantages for introducing permanent magnets into the rotor flux barriers, some of which are to saturate the rotor iron ribs, to increase the motor torque density and to improve the power factor. Moreover, the d-axis and q-axis inductances are of great importance to simultaneously achieve maximum developed torque and low torque ripple. Therefore, sensitivity analysis of the rotor geometry of an 8-pole external-rotor permanent magnet assisted synchronous reluctance motor is performed. Several magnetically accurate finite element analyses (FEA) are conducted to characterize the electromagnetic performance of the motor. The analyses validate torque and power factor equations for the proposed external-rotor motor. Based upon the obtained results and due to an additional term, permanent magnet torque, added to the reluctance torque, the electromagnetic torque of the PMaSynRM increases.

Keywords: Permanent magnet assisted synchronous reluctance motor, flux barrier, flux carrier, electromagnetic torque, and power factor.

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3360 Impact Deformation and Fracture Behaviour of Cobalt-Based Haynes 188 Superalloy

Authors: Woei-Shyan Lee, Hao-Chien Kao

Abstract:

The impact deformation and fracture behaviour of cobalt-based Haynes 188 superalloy are investigated by means of a split Hopkinson pressure bar. Impact tests are performed at strain rates ranging from 1×103 s-1 to 5×103 s-1 and temperatures between 25°C and 800°C. The experimental results indicate that the flow response and fracture characteristics of cobalt-based Haynes 188 superalloy are significantly dependent on the strain rate and temperature. The flow stress, work hardening rate and strain rate sensitivity all increase with increasing strain rate or decreasing temperature. It is shown that the impact response of the Haynes 188 specimens is adequately described by the Zerilli-Armstrong fcc model. The fracture analysis results indicate that the Haynes 188 specimens fail predominantly as the result of intensive localised shearing. Furthermore, it is shown that the flow localisation effect leads to the formation of adiabatic shear bands. The fracture surfaces of the deformed Haynes 188 specimens are characterised by dimple- and / or cleavage-like structure with knobby features. The knobby features are thought to be the result of a rise in the local temperature to a value greater than the melting point.

Keywords: Haynes 188 alloy, impact, strain rate and temperature effect, adiabatic shearing.

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3359 Impact of Foreign Aid and Levels of Education on Democracy in Pakistan

Authors: H. Mahmood, M. W. Siddiqi, A. Iqbal, M. A. Tabassum

Abstract:

This study examines the relationships between foreign aid, levels of schooling and democracy for Pakistan using the ARDL cointegration approach. The results of study provide strong evidence for fairly robust long run as well as short run relationships among these variables for the period 1973-2008. The results state that foreign aid and primary school enrollments have negative impact on democracy index and high school enrollments have positive impact on democracy index in Pakistan. The study suggests for promotion of education levels and relies on local resources instead of foreign aid for a good quality of political institutions in Pakistan.

Keywords: Cointegration, Democracy, Education, Foreign Aid

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3358 The Comparation of Activation Nuclear Factor Kappa Beta (NFKB) at Rattus Novergicus Strain Wistar Induced by Various Duration High Fat Diet (HFD)

Authors: Titin Andri Wihastuti, Djanggan Sargowo

Abstract:

NFκB is a transcription factor regulating many function of the vessel wall. In the normal condition , NFκB is revealed diffuse cytoplasmic expressionsuggesting that the system is inactive. The presence of activation NFκB provide a potential pathway for the rapid transcriptional of a variety of genes encoding cytokines, growth factors, adhesion molecules and procoagulatory factors. It is likely to play an important role in chronic inflamatory disease involved atherosclerosis. There are many stimuli with the potential to active NFκB, including hyperlipidemia. We used 24 mice which was divided in 6 groups. The HFD given by et libitum procedure during 2, 4, and 6 months. The parameters in this study were the amount of NFKB activation ,H2O2 as ROS and VCAM-1 as a product of NFKB activation. H2O2 colorimetryc assay performed directly using Anti Rat H2O2 ELISA Kit. The NFKB and VCAM-1 detection obtained from aorta mice, measured by ELISA kit and imunohistochemistry. There was a significant difference activation of H2O2, NFKB and VCAM-1 level at induce HFD after 2, 4 and 6 months. It suggest that HFD induce ROS formation and increase the activation of NFKB as one of atherosclerosis marker that caused by hyperlipidemia as classical atheroschlerosis risk factor.

Keywords: High Fat Diet, NFKB, H2O2, atherosclerosis

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3357 Selective Transverse Modes in a Diode End- Pumped Nd:Yag Pulsed Laser

Authors: M. Mohamadi, M. Mostamand, M. Moosavi, M. Soltanolkotabi

Abstract:

The output beam quality of multi transverse modes of laser, are relatively poor. In order to obtain better beam quality, one may use an aperture inside the laser resonator. In this case, various transverse modes can be selected. We have selected various transverse modes both by simulation and doing experiment. By inserting a circular aperture inside the diode end-pumped Nd:YAG pulsed laser resonator, we have obtained 00 TEM , 01 TEM , 20 TEM and have studied which parameters, can change the mode shape. Then, we have determined the beam quality factor of TEM00 gaussian mode.

Keywords: Beam shape, Transverse mode , Beam quality factor

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3356 Control Strategy of SRM Converters for Power Quality Improvement

Authors: Yogesh Pahariya, Rakesh Saxena, Biswaroop Sarkar

Abstract:

The selection of control strategy depends on the converters of the drive including power, speed, performance and the possible system costs. A number of attempts were therefore made in recent times to develop novel power electronic converter structures for SRM drives, based on the utilization. Many of the converters with variable speed drives have no input power factor correction circuits. This results in harmonic pollution of the utility supply, which should be avoided. The effect of power factor variation in terms of harmonic content is also analyzed in this study. The proposed topologies were simulated using MATLAB / Simulink software package and the results are obtained.

Keywords: Harmonic Pollution, Power Electronic Converter, Power Quality, Simulation.

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3355 Experimental Study on the Floor Vibration Evaluation of Concrete Slab for Existing Buildings

Authors: Yong-Taeg Lee, Jun-Ho Na, Seung-Hun Kim, Seong-Uk Hong

Abstract:

Damages from noise and vibration are increasing every year, most of which are noises between floors in deteriorated building caused by floor impact sound. In this study, the concrete slab measured vibration impact sound for evaluation floor vibration of deteriorated buildings that fails to satisfy with the minimum thickness. In this experimental study, the vibration scale by impact sound was calibrated and compared with ISO and AIJ standard for vibration. The results show that vibration in slab with thickness used in existing building reach human perception levels.

Keywords: Vibration, Frequency, Accelerometer, Concrete slab.

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3354 A Study of Shear Stress Intensity Factor of PP and HDPE by a Modified Experimental Method together with FEM

Authors: Md. Shafiqul Islam, Abdullah Khan, Sharon Kao-Walter, Li Jian

Abstract:

Shear testing is one of the most complex testing areas where available methods and specimen geometries are different from each other. Therefore, a modified shear test specimen (MSTS) combining the simple uniaxial test with a zone of interest (ZOI) is tested which gives almost the pure shear. In this study, material parameters of polypropylene (PP) and high density polyethylene (HDPE) are first measured by tensile tests with a dogbone shaped specimen. These parameters are then used as an input for the finite element analysis. Secondly, a specially designed specimen (MSTS) is used to perform the shear stress tests in a tensile testing machine to get the results in terms of forces and extension, crack initiation etc. Scanning Electron Microscopy (SEM) is also performed on the shear fracture surface to find material behavior. These experiments are then simulated by finite element method and compared with the experimental results in order to confirm the simulation model. Shear stress state is inspected to find the usability of the proposed shear specimen. Finally, a geometry correction factor can be established for these two materials in this specific loading and geometry with notch using Linear Elastic Fracture Mechanics (LEFM). By these results, strain energy of shear failure and stress intensity factor (SIF) of shear of these two polymers are discussed in the special application of the screw cap opening of the medical or food packages with a temper evidence safety solution.

Keywords: Shear test specimen, Stress intensity factor, Finite Element simulation, Scanning electron microscopy, Screw cap opening.

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3353 Fuzzy Based Environmental System Approach for Impact Assessment - Case Studies

Authors: Marius Pislaru, Alexandru F. Trandabat

Abstract:

Environmental studies have expanded dramatically all over the world in the past few years. Nowadays businesses interact with society and the environment in ways that put their mark on both sides. Efforts improving human standard living, through the control of nature and the development of new products, have also resulted in contamination of the environment. Consequently companies play an important role in environmental sustainability of a region or country. Therefore we can say that a company's sustainable development is strictly dependent on the environment. This article presents a fuzzy model to evaluate a company's environmental impact. Article illustrates an example of the automotive industry in order to prove the usefulness of using such a model.

Keywords: fuzzy approach, environmental impact assessment, sustainability

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3352 Stress Variation around a Circular Hole in Functionally Graded Plate under Bending

Authors: Parveen K. Saini, Mayank Kushwaha

Abstract:

The influence of material property variation on stress concentration factor (SCF) due to the presence of a circular hole in a functionally graded material (FGM) plate is studied in this paper. A numerical method based on complex variable theory of elasticity is used to investigate the problem. To achieve the material property, variation plate is decomposed into a number of rings. In this research work, Young’s modulus is assumed to be varying exponentially and it is found that stress concentration factor can be reduced by increasing Young’s modulus progressively away from the hole.

Keywords: Stress Concentration, Circular Hole, FGM Plate, Bending.

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3351 The Role of European Union in Global Governance

Authors: Yrfet Shkreli

Abstract:

Despite all the wide research and literature on the subject, changing and challenging times often present themselves with new objectives, fluid politics, and everlasting point of views. Much is said about the subject and the trend nowadays is watching every European Union (EU) intervention as a form of neo colonialism or a form of establishing new markets. The paper will try to establish a perspective on EU influences, policies and impacts analyzed from multidimensional point of view, not limiting itself on a narrow external dimension, focusing on a broader understanding of it diverse contribution to global governance and peace keeping. Tending to be critical, this paper tends to fall out of extremes, nether holding a Eurocentric position, nor falling for cheap critic to the whole failures and impact of EU policies. The ambition is to show EU as a contributing factor while keeping in mind its nature as a multi layered actor and with not necessarily coinciding interests among its member states.

Keywords: European Union, global governance, globalization, normative power.

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3350 Static Analysis and Pseudostatic Slope Stability

Authors: Meftah Ali

Abstract:

This article aims to analyze the static stability and pseudostatic slope by using different methods such as: Bishop method, Junbu, Ordinary, Morgenstern-price and GLE. The two dimensional modeling of slope stability under various loading as: the earthquake effect, the water level and road mobile charges. The results show that the slope is stable in the static case without water, but in other cases, the slope lost its stability and give unstable. The calculation of safety factor is to evaluate the stability of the slope using the limit equilibrium method despite the difference between the results obtained by these methods that do not rely on the same assumptions. In the end, the results of this study illuminate well the influence of the action of water, moving loads and the earthquake on the stability of the slope.

Keywords: Slope stability, pseudo static, safety factor, limit equilibrium.

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3349 Comparative Life Cycle Assessment of High Barrier Polymer Packaging for Selecting Resource Efficient and Environmentally Low-Impact Materials

Authors: D. Kliaugaitė, J. K, Staniškis

Abstract:

In this study tree types of multilayer gas barrier plastic packaging films were compared using life cycle assessment as a tool for resource efficient and environmentally low-impact materials selection. The first type of multilayer packaging film (PET-AlOx/LDPE) consists of polyethylene terephthalate with barrier layer AlOx (PET-AlOx) and low density polyethylene (LDPE). The second type of polymer film (PET/PE-EVOH-PE) is made of polyethylene terephthalate (PET) and co-extrusion film PE-EVOH-PE as barrier layer. And the third one type of multilayer packaging film (PET-PVOH/LDPE) is formed from polyethylene terephthalate with barrier layer PVOH (PET-PVOH) and low density polyethylene (LDPE).

All of analyzed packaging has significant impact to resource depletion, because of raw materials extraction and energy use and production of different kind of plastics. Nevertheless the impact generated during life cycle of functional unit of II type of packaging (PET/PE-EVOH-PE) was about 25% lower than impact generated by I type (PET-AlOx/LDPE) and III type (PET-PVOH/LDPE) of packaging.

Result revealed that the contribution of different gas barrier type to the overall environmental problem of packaging is not significant. The impact are mostly generated by using energy and materials during raw material extraction and production of different plastic materials as plastic polymers material as PE, LDPE and PET, but not gas barrier materials as AlOx, PVOH and EVOH.

The LCA results could be useful in different decision-making processes, for selecting resource efficient and environmentally low-impact materials.

Keywords: Polymer packaging, life cycle assessment, resource efficiency.

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3348 Numerical Investigation on Optimizing Fatigue Life in a Lap Joint Structure

Authors: P. Zamani, S. Mohajerzadeh, R. Masoudinejad, Kh. Farhangdoost

Abstract:

Riveting process is one of the important ways to keep fastening the lap joints in aircraft structures. Failure of aircraft lap joints directly depends on the stress field in the joint. An important application of riveting process is in the construction of aircraft fuselage structures. In this paper, a 3D finite element method is carried out in order to optimize residual stress field in a riveted lap joint and also to estimate its fatigue life. In continue, a number of experiments are designed and analyzed using design of experiments (DOE). Then, Taguchi method is used to select an optimized case between different levels of each factor. Besides that, the factor which affects the most on residual stress field is investigated. Such optimized case provides the maximum residual stress field. Fatigue life of the optimized joint is estimated by Paris-Erdogan law. Stress intensity factors (SIFs) are calculated using both finite element analysis and experimental formula. In addition, the effect of residual stress field, geometry and secondary bending are considered in SIF calculation. A good agreement is found between results of such methods. Comparison between optimized fatigue life and fatigue life of other joints has shown an improvement in the joint’s life.

Keywords: Fatigue life, Residual stress, Riveting process, Stress intensity factor, Taguchi method.

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3347 Trade Policy Incentives and Economic Growth in Nigeria

Authors: Emmanuel Dele Balogun

Abstract:

This paper analyzes, using descriptive statistics and econometrics data which span the period 1981 to 2014 to gauge the effects of trade policy incentives on economic growth in Nigeria. It argues that the provided incentives penalize economic growth during pre-trade liberalization eras, but stimulated a rapid increase in total factor productivity during the post-liberalization period of 2000 to 2014. The trend analysis shows that Nigeria maintained high tariff walls in economic regulation eras which became low in post liberalization era. The protections were in favor of infant industries, which were mainly appendages of multinationals but against imports of competing food and finished consumer products. The trade openness index confirms the undue exposure of Nigeria’s economy to the vagaries of international market shocks; while banking sector recapitalization and new listing of telecommunications companies deepened the financial markets in post-liberalization era. The structure of economic incentives was biased in favor of construction, trade and services, but against the real sector despite protectionist policies. Total Factor Productivity (TFP) estimates show that the Nigerian economy suffered stagnation in pre-liberalization eras, but experienced rapid growth rates in post-liberalization eras. The regression results relating trade policy incentives to TFP growth rate yielded a significant but negative intercept suggesting that a non-interventionist policy could be detrimental to economic progress, while protective tariff which limits imports of competing products could spur productivity gains in domestic import substitutes beyond factor growth with market liberalization. The main constraint to the effectiveness of trade policy incentives is the failure of benefiting industries to leverage on the domestic factor endowments of the nation. This paper concludes that there is the need to review the current economic transformation strategies urgently with a view to provide policymakers with a better understanding of the most viable options that could make for rapid success.

Keywords: Trade Policies, macroeconomic incentives, total factor productivity and economic growth.

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3346 The State-of-Art Environmental Impact Assessment: An Overview

Authors: Tsolmon Tumenjargal, Muhammad Hassan Khalil, Wu Yao Guo

Abstract:

The research on the effectiveness of environmental assessment (EA) is a milestone effort to evaluate the state of the field, including many contributors related with a lot of countries since more than two decades. In the 1960s, there was a surge of interest between modern industrialized countries over unexpected opposite effects of technical invention. The interest led to choice of approaches for assessing and prediction the impressions of technology and advancement for social and economic, state health and safety, solidity and the circumstances. These are consisting of risk assessment, technology assessment, environmental impact assessment and costbenefit analysis. In this research contribution, the authors have described the research status for environmental assessment in cumulative environmental system. This article discusses the methods for cumulative effect assessment (CEA).

Keywords: Cumulative effect assessment, Environmental impact assessment.

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3345 The Impact of the Information Technologies on the Accounting Department of the Romanian Companies

Authors: Valentin Florentin Dumitru

Abstract:

The need to use high volumes of data and the high competition are only two reasons which make necessary the use of information technologies. The objective of our research is to establish the impact of information technologies on the accounting department of the Romanian companies. In order to achieve it, starting from the literature review we made an empirical research based on a questionnaire. We investigated the types of technologies used, the reasons which led to the implementation of certain technologies, the benefits brought by the use of the information technologies, the difficulties brought by the implementation and the future effects of the applications. The conclusions show that there is an evolution in the degree of implementation of the information technologies in the Romanian companies, compared with the results of other studies conducted a few years before.

Keywords: Information technologies, impact, company, Romania, empirical study.

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3344 Electrical Properties of n-CdO/p-Si Heterojunction Diode Fabricated by Sol Gel

Authors: S.Aksoy, Y.Caglar

Abstract:

n-CdO/p-Si heterojunction diode was fabricated using sol-gel spin coating technique which is a low cost and easily scalable method for preparing of semiconductor films. The structural and morphological properties of CdO film were investigated. The X-ray diffraction (XRD) spectra indicated that the film was of polycrystalline nature. The scanning electron microscopy (SEM) images indicate that the surface morphology CdO film consists of the clusters formed with the coming together of the nanoparticles. The electrical characterization of Au/n-CdO/p–Si/Al heterojunction diode was investigated by current-voltage. The ideality factor of the diode was found to be 3.02 for room temperature. The reverse current of the diode strongly increased with illumination intensity of 100 mWcm-2 and the diode gave a maximum open circuit voltage Voc of 0.04 V and short-circuits current Isc of 9.92×10-9 A.

Keywords: CdO, heterojunction semiconductor devices, ideality factor, current-voltage characteristics

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3343 Consideration Factors of Moving to a New Destination for Coastland Residents Under Global Warming

Authors: Ya-Fen Lee, Yun-Yao Chi, Cing-Hong Hung

Abstract:

Because of the global warming and the rising sea level, residents living in southwestern coastland, Taiwan are faced with the submerged land and may move to higher elevation area. It is desirable to discuss the key consideration factor for selecting the migration location under five dimensions of ಯ security”, “health”, “convenience”, “comfort” and “socio-economic” based on the document reviews. This paper uses the Structural Equation Modeling (SEM) and the questionnaire survey. The analysis results show that the convenience is the most key factor for residents in Taiwan. 

Keywords: Global warming, migration, structural equation modelling, questionnaire survey.

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3342 Neutronic Study of Two Reactor Cores Cooled with Light and Heavy Water Using Computation Method

Authors: Z. Gholamzadeh, A. Zali, S. A. H. Feghhi, C. Tenreiro, Y. Kadi, M. Rezazadeh, M. Aref

Abstract:

Most HWRs currently use natural uranium fuel. Using enriched uranium fuel results in a significant improvement in fuel cycle costs and uranium utilization. On the other hand, reactivity changes of HWRs over the full range of operating conditions from cold shutdown to full power are small. This reduces the required reactivity worth of control devices and minimizes local flux distribution perturbations, minimizing potential problems due to transient local overheating of fuel. Analyzing heavy water effectiveness on neutronic parameters such as enrichment requirements, peaking factor and reactivity is important and should pay attention as primary concepts of a HWR core designing. Two nuclear nuclear reactors of CANDU-type and hexagonal-type reactor cores of 33 fuel assemblies and 19 assemblies in 1.04 P/D have been respectively simulated using MCNP-4C code. Using heavy water and light water as moderator have been compared for achieving less reactivity insertion and enrichment requirements. Two fuel matrixes of (232Th/235U)O2 and (238/235U)O2 have been compared to achieve more economical and safe design. Heavy water not only decreased enrichment needs, but it concluded in negative reactivity insertions during moderator density variations. Thorium oxide fuel assemblies of 2.3% enrichment loaded into the core of heavy water moderator resulted in 0.751 fission to absorption ratio and peaking factor of 1.7 using. Heavy water not only provides negative reactivity insertion during temperature raises which changes moderator density but concluded in 2 to 10 kg reduction of enrichment requirements, depend on geometry type.

Keywords: MCNP-4C, Reactor core, Multiplication factor, Reactivity, Peaking factor.

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3341 Self-evolving Neural Networks Based On PSO and JPSO Algorithms

Authors: Abdussamad Ismail, Dong-Sheng Jeng

Abstract:

A self-evolution algorithm for optimizing neural networks using a combination of PSO and JPSO is proposed. The algorithm optimizes both the network topology and parameters simultaneously with the aim of achieving desired accuracy with less complicated networks. The performance of the proposed approach is compared with conventional back-propagation networks using several synthetic functions, with better results in the case of the former. The proposed algorithm is also implemented on slope stability problem to estimate the critical factor of safety. Based on the results obtained, the proposed self evolving network produced a better estimate of critical safety factor in comparison to conventional BPN network.

Keywords: Neural networks, Topology evolution, Particle swarm optimization.

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