Search results for: internal attention
Commenced in January 2007
Frequency: Monthly
Edition: International
Paper Count: 1564

Search results for: internal attention

784 A Multilevel Comparative Assessment Approach to International Services Trade Competitiveness: The Case of Romania and Bulgaria

Authors: Ana Bobirca, Paul-Gabriel Miclaus

Abstract:

International competitiveness receives much attention nowadays, but up to now its assessment has been heavily based on manufacturing industry statistics. This paper addresses the need for competitiveness indicators that cover the service sector and sets out a multilevel framework for measuring international services trade competitiveness. The approach undertaken here aims at comparatively examining the international competitiveness of the EU-25 (the twenty-five European Union member states before the 1st of January 2007), Romanian and Bulgarian services trade, as well as the last two countries- structure of specialization on the EU-25 services market. The primary changes in the international competitiveness of three major services sectors – transportation, travel and other services - are analyzed. This research attempts to determine the ability of the two recent European Union (EU) member states to contend with the challenges that might arise from the hard competition within the enlarged EU, in the field of services trade.

Keywords: Bulgaria, EU-25, international competitiveness, international services trade, Romania.

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783 Structure and Functions of Urban Surface Water System in Coastal Areas: The Case of Almere

Authors: Tao Zou, Zhengnan Zhou

Abstract:

In the context of global climate change, flooding and sea level rise is increasingly threatening coastal urban areas, in which large population is continuously concentrated. Dutch experiences in urban water system management provide high reference value for sustainable coastal urban development projects. Preliminary studies shows the urban water system in Almere, a typical Dutch polder city, have three kinds of operational modes, achieving functions as: (1) coastline control – strong multiple damming system prevents from storm surges and maintains sufficient capacity upon risks; (2) high flexibility – large area and widely scattered open water system greatly reduce local runoff and water level fluctuation; (3) internal water maintenance – weir and sluice system maintains relatively stable water level, providing excellent boating and landscaping service, coupling with water circulating model maintaining better water quality. Almere has provided plenty of hints and experiences for ongoing development of coastal cities in emerging economies.

Keywords: Coastal area, resilience, sustainable urban watersystem, water circulation.

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782 Multi-Agent System Architecture Oriented Prometheus Methodology Design for Reverse Logistics

Authors: F. Lhafiane, A. Elbyed, M. Bouchoum

Abstract:

The design of Reverse logistics Network has attracted growing attention with the stringent pressures from both environmental awareness and business sustainability. Reverse logistical activities include return, remanufacture, disassemble and dispose of products can be quite complex to manage. In addition, demand can be difficult to predict, and decision making is one of the challenges task in such network. This complexity has amplified the need to develop an integrated architecture for product return as an enterprise system. The main purpose of this paper is to design Multi Agent System (MAS) architecture using the Prometheus methodology to efficiently manage reverse logistics processes. The proposed MAS architecture includes five types of agents: Gate keeping Agent, Collection Agent, Sorting Agent, Processing Agent and Disposal Agent which act respectively during the five steps of reverse logistics Network.

Keywords: Reverse logistics, multi agent system, Prometheus methodology.

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781 Denial of Service (DOS) Attack and Its Possible Solutions in VANET

Authors: Halabi Hasbullah, Irshad Ahmed Soomro, Jamalul-lail Ab Manan

Abstract:

Vehicular Ad-hoc Network (VANET) is taking more attention in automotive industry due to the safety concern of human lives on roads. Security is one of the safety aspects in VANET. To be secure, network availability must be obtained at all times since availability of the network is critically needed when a node sends any life critical information to other nodes. However, it can be expected that security attacks are likely to increase in the coming future due to more and more wireless applications being developed and deployed onto the well-known expose nature of the wireless medium. In this respect, the network availability is exposed to many types of attacks. In this paper, Denial of Service (DOS) attack on network availability is presented and its severity level in VANET environment is elaborated. A model to secure the VANET from the DOS attacks has been developed and some possible solutions to overcome the attacks have been discussed.

Keywords: Vehicular Ad hoc Network (VANET); security;availability; security attack; Denial of Service (DOS).

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780 Interval Type-2 Fuzzy Vibration Control of an ERF Embedded Smart Structure

Authors: Chih-Jer Lin, Chun-Ying Lee, Ying Liu, Chiang-Ho Cheng

Abstract:

The main objective of this article is to present the semi-active vibration control using an electro-rheological fluid embedded sandwich structure for a cantilever beam. ER fluid is a smart material, which cause the suspended particles polarize and connect each other to form chain. The stiffness and damping coefficients of the ER fluid can be changed in 10 micro seconds; therefore, ERF is suitable to become the material embedded in the tunable vibration absorber to become a smart absorber. For the ERF smart material embedded structure, the fuzzy control law depends on the experimental expert database and the proposed self-tuning strategy. The electric field is controlled by a CRIO embedded system to implement the real application. This study investigates the different performances using the Type-1 fuzzy and interval Type-2 fuzzy controllers. The Interval type-2 fuzzy control is used to improve the modeling uncertainties for this ERF embedded shock absorber. The self-tuning vibration controllers using Type-1 and Interval Type-2 fuzzy law are implemented to the shock absorber system. Based on the resulting performance, Internal Type-2 fuzzy is better than the traditional Type-1 fuzzy control for this vibration control system.

 

Keywords: Electro-Rheological Fluid, Semi-active vibration control, shock absorber, type 2 fuzzy control.

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779 Performance Analysis of Certificateless Signature for IKE Authentication

Authors: Nazrul M. Ahmad, Asrul H. Yaacob, Ridza Fauzi, Alireza Khorram

Abstract:

Elliptic curve-based certificateless signature is slowly gaining attention due to its ability to retain the efficiency of identity-based signature to eliminate the need of certificate management while it does not suffer from inherent private key escrow problem. Generally, cryptosystem based on elliptic curve offers equivalent security strength at smaller key sizes compared to conventional cryptosystem such as RSA which results in faster computations and efficient use of computing power, bandwidth, and storage. This paper proposes to implement certificateless signature based on bilinear pairing to structure the framework of IKE authentication. In this paper, we perform a comparative analysis of certificateless signature scheme with a well-known RSA scheme and also present the experimental results in the context of signing and verification execution times. By generalizing our observations, we discuss the different trade-offs involved in implementing IKE authentication by using certificateless signature.

Keywords: Certificateless signature, IPSec, RSA signature, IKE authentication.

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778 The Law of Treaties and National Security of Islamic Republic of Iran

Authors: S. M. Tavakoli Sani, M. Sabbet Moghadam, Y. Khorram Farhadi, Iraj Rezayi Nejad

Abstract:

The concept of national security in Iran is a permanently effective factor in acceptance or rejection of many international obligations. These obligations had been defined according to the type of legislation of Iran in many aspects. Therefore, there are several treaties at international level which requires Iran’s security to come in contact with obligations in these treaties in a way that an obstacle to join to them and their passage in parliament. This issue is a typical category which every country pays attention to be accepted in treaties or to include their national security in that treaties and also they can see the related treaties from this perspective, but this issue that 'what is the concept of Iran’s national security', and 'To what extent it is changed in recent years, especially after Islamic Revolution' are important issues that can be criticized. Thus, this study is trying to assess singed treaties from the perspective of Iran’s national security according of the true meaning of treaty and to investigate how the international treaties may be in conflict with Iran’s national security.

Keywords: Treaties, national security, Iran, Islamic Revolution.

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777 Promoting Electric Vehicles for Sustainable Urban Transport: How to Do It This Time Right

Authors: Reinhard Haas, Amela Ajanovic

Abstract:

In recent years various types of electric vehicles has gained again increasing attention as an environmentally benign technology in transport. Especially for urban areas with high local pollution this Zero-emission technology (at the point of use) is considered to provide proper solutions. Yet, the bad economics and the limited driving ranges are still major barriers for a broader market penetration of battery electric vehicles (BEV) and of fuel cell vehicles (FCV). The major result of our analyses is that the most important precondition for a further dissemination of BEV in urban areas are emission-free zones. This is an instrument which allows the promotion of BEV without providing excessive subsidies. In addition, it is important to note that the full benefits of EV can only be harvested if the electricity used is produced from renewable energy sources. That is to say, it has to be ensured that the use of BEV in urban areas is clearly linked to a green electricity purchase model. And moreover, the introduction of a CO2- emission-based tax system would support this requirement.

Keywords: Electric vehicles, economics, policies, history.

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776 A Worst Case Estimation of the Inspection Rate by a Berthing Policy in a Container Terminal

Authors: K.H. Yang

Abstract:

After the terrorist attack on September 11, 2001 in U.S., the container security issue got high attention, especially by U.S. government, which deployed a lot of measures to promote or improve security systems. U.S. government not only enhances its national security system, but allies with other countries against the potential terrorist attacks in the future. For example CSI (Container Security Initiative), it encourages foreign ports outside U.S. to become CSI ports as a part of U.S. anti-terrorism network. Although promotion of the security could partly reach the goal of anti-terrorism, that will influence the efficiency of container supply chain, which is the main concern when implementing the inspection measurements. This paper proposes a quick estimation methodology for an inspection service rate by a berth allocation heuristic such that the inspection activities will not affect the original container supply chain. Theoretical and simulation results show this approach is effective.

Keywords: Berth allocation, Container, Heuristic, Inspection.

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775 Managing User Expectations in Information Systems Development

Authors: Linda, Sau-ling Lai

Abstract:

This paper provides new ways to explore the old problem of failure of information systems development in an organisation. Based on the theory of cognitive dissonance, information systems (IS) failure is defined as a gap between what the users expect from an information system and how well these expectations are met by the perceived performance of the delivered system. Bridging the expectation-perception gap requires that IS professionals make a radical change from being the proprietor of information systems and products to being service providers. In order to deliver systems and services that IS users perceive as valuable, IS people must become expert in determining and assessing users- expectations and perceptions. It is also suggested that the IS community, in general, has given relatively little attention to the front-end process of requirements specification for IS development. There is a simplistic belief that requirements are obtainable from users, they are then translatable into a formal specification. The process of information needs analysis is problematic and worthy of investigation.

Keywords: Information Systems Development, Cognitive Dissonance, Expectation-Perception Gap, Requirements Analysis.

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774 Proposals for the Thermal Regulation of Buildings in Algeria: An Energy Label for Social Housing

Authors: Marco Morini, Nicolandrea Calabrese, Dario Chello

Abstract:

Despite the international commitment of Algeria towards the development of energy efficiency and renewable energy in the country, the internal energy demand has been continuously growing during the last decade due to the substantial increase of population and of living conditions, which in turn has led to an unprecedented expansion of the residential building sector. The RTB (Thermal Building Regulation) is the technical document that establishes the calculation framework for the thermal performance of buildings in Algeria, setting up minimum obligatory targets for the thermal performance of new buildings. An update of this regulation is due in the coming years and this paper discusses some proposals in this regard, with the aim to improve the energy efficiency of the building sector, particularly with regard to social housing. In particular, it proposes a methodology for drafting an energy performance label of new Algerian residential buildings, moving from the results of the thermal compliance verification and sizing of technical systems as defined in the RTB. Such an energy performance label – whose calculation method is briefly described in the paper – aims to raise citizens' awareness of the benefits of energy efficiency. It can represent the first step in a process of integrating technical installations into the calculation of the energy performance of buildings in Algeria.

Keywords: building, energy certification, energy efficiency, social housing, international cooperation, Mediterranean Region

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773 Knowledge Management (KM) Practices - A Study of KM Adoption among Doctors in Kuwait

Authors: B. Alajmi, L. Marouf, A. S. Chaudhry

Abstract:

Knowledge management is considered as an important factor in improving health care services. KM facilitates the transfer of existing knowledge and the development of new knowledge in hospitals. This paper reviews practices adopted by doctors in Kuwait for capturing, sharing, and generating knowledge. It also discusses the perceived impact of KM practices on performance of hospitals. Based on a survey of 277 doctors, the study found that KM practices among doctors in the sampled hospitals were not very effective. Little attention was paid to the main activities that support the transfer of expertise among doctors in hospitals. However, as predicted by previous studies, good km practices were perceived by doctors to have a positive impact on performance of hospitals. It was concluded that through effective KM practices hospitals could improve the services they provide. Documentation of best practices and capturing of lessons learnt for re-use of knowledge could help transform the hospitals into learning organizations.

Keywords: Health Sector, Hospitals, Knowledge Management, Kuwait, Tools and Practices.

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772 EEG-Based Screening Tool for School Student’s Brain Disorders Using Machine Learning Algorithms

Authors: Abdelrahman A. Ramzy, Bassel S. Abdallah, Mohamed E. Bahgat, Sarah M. Abdelkader, Sherif H. ElGohary

Abstract:

Attention-Deficit/Hyperactivity Disorder (ADHD), epilepsy, and autism affect millions of children worldwide, many of which are undiagnosed despite the fact that all of these disorders are detectable in early childhood. Late diagnosis can cause severe problems due to the late treatment and to the misconceptions and lack of awareness as a whole towards these disorders. Moreover, electroencephalography (EEG) has played a vital role in the assessment of neural function in children. Therefore, quantitative EEG measurement will be utilized as a tool for use in the evaluation of patients who may have ADHD, epilepsy, and autism. We propose a screening tool that uses EEG signals and machine learning algorithms to detect these disorders at an early age in an automated manner. The proposed classifiers used with epilepsy as a step taken for the work done so far, provided an accuracy of approximately 97% using SVM, Naïve Bayes and Decision tree, while 98% using KNN, which gives hope for the work yet to be conducted.

Keywords: ADHD, autism, epilepsy, EEG, SVM.

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771 Sovereign Credit Risk Measures

Authors: Kristýna Pokorná, Petr Teplý

Abstract:

This paper focuses on sovereign credit risk meaning a hot topic related to the current Eurozone crisis. In the light of the recent financial crisis, market perception of the creditworthiness of individual sovereigns has changed significantly. Before the outbreak of the financial crisis, market participants did not differentiate between credit risk born by individual states despite different levels of public indebtedness. In the proceeding of the financial crisis, the market participants became aware of the worsening fiscal situation in the European countries and started to discriminate among government issuers. Concerns about the increasing sovereign risk were reflected in surging sovereign risk premium. The main of this paper is to shed light on the characteristics of the sovereign risk with the special attention paid to the mutual relation between credit spread and the CDS premium as the main measures of the sovereign risk premium.

Keywords: cointegration, credit default swap, credit risk, credit spread, sovereign risk

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770 The Use Management of the Knowledge Management and the Information Technologies in the Competitive Strategy of a Self-Propelling Industry

Authors: Guerrero Ramírez Sandra, Ramos Salinas Norma Maricela, Muriel Amezcua Vanesa

Abstract:

This article presents the beginning of a wider study that intends to demonstrate how within organizations of the automotive industry from the city of Querétaro. Knowledge management and technological management are required, as well as people’s initiative and the interaction embedded at the interior of it, with the appropriate environment that facilitates information conversion with wide information technologies management (ITM) range. A company was identified for the pilot study of this research, where descriptive and inferential research information was obtained. The results of the pilot suggest that some respondents did noted entity the knowledge management topic, even if staffs have access to information technology (IT) that serve to enhance access to knowledge (through internet, email, databases, external and internal company personnel, suppliers, customers and competitors) data, this implicates that there are Knowledge Management (KM) problems. The data shows that academically well-prepared organizations normally do not recognize the importance of knowledge in the business, nor in the implementation of it, which at the end is a great influence on how to manage it, so that it should guide the company to greater in sight towards a competitive strategy search, given that the company has an excellent technological infrastructure and KM was not exploited. Cultural diversity is another factor that was observed by the staff.

Keywords: Knowledge management, technological knowledge management, technology information management.

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769 Contact Stress on the Surface of Gear Teeth with Different Profile

Authors: K. Farhangdoost, H. Heirani

Abstract:

Contact stress is an important problem in industry. This is a problem that in the first attention may be don-t appears, but disregard of these stresses cause a lot of damages in machines. These stresses occur at locations such as gear teeth, bearings, cams and between a locomotive wheel and the railroad rail. These stresses cause failure by excessive elastic deformation, yielding and fracture. In this paper we intend show the effective parameters in contact stress and ponder effect of curvature. In this paper we study contact stresses on the surface of gear teeth and compare these stresses for four popular profiles of gear teeth (involute, cycloid, epicycloids, and hypocycloid). We study this problem with mathematical and finite element methods and compare these two methods on different profile surfaces.

Keywords: Contact stress, Cycloid, Epicycloids, Finite element, Gear, Hypocycloid, Involute, Radius of curvature.

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768 Development and Validation of the Response to Stressful Situations Scale in the General Population

Authors: C. Barreto Carvalho, C. da Motta, M. Sousa, J. Cabral, A. L. Carvalho, E. B. Peixoto

Abstract:

The aim of the current study was to develop and validate a Response to Stressful Situations Scale (RSSS) for the Portuguese population. This scale assesses the degree of stress experienced in scenarios that can constitute positive, negative and more neutral stressors, and also describes the physiological, emotional and behavioral reactions to those events according to their intensity. These scenarios include typical stressor scenarios relevant to patients with schizophrenia, which are currently absent from most scales, assessing specific risks that these stressors may bring on subjects, which may prove useful in non-clinical and clinical populations (i.e. Patients with mood or anxiety disorders, schizophrenia). Results from Principal Components Analysis and Confirmatory Factor Analysis of two adult samples from general population allowed to confirm a three-factor model with good fit indices: χ2 (144)= 370.211, p = 0.000; GFI = 0.928; CFI = 0.927; TLI = 0.914, RMSEA = 0.055, P(rmsea ≤0.005) = .096; PCFI = .781. Further data analysis of the scale revealed that RSSS is an adequate assessment tool of stress response in adults to be used in further research and clinical settings, with good psychometric characteristics, adequate divergent and convergent validity, good temporal stability and high internal consistency.

Keywords: Assessment, stress events, stress response, stress vulnerability.

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767 Assessment of Compaction Temperatures on Hot Mix Asphalt (HMA) Properties

Authors: Houman Saedi

Abstract:

Hot Mix Asphalt (HMA) is one of the most commonest constructed asphalts in Iran and the quality control of constructed roads with HMA have been always paid due attention by researchers. The quality control of constructed roads with this method is being usually carried out by measuring volumetric parameters of HMA marshall samples. One of the important parameters that has a critical role in changing these volumetric parameters is “compaction temperature"; which as a result of its changing, volumetric parameters of Marshall Samples and subsequently constructed asphalt is encountered with variations. In this study, considering the necessity of preservation of the compaction temperature, the effect of various temperatures on Hot Mix Asphalt (HMA) samples properties has been evaluated. As well, to evaluate the effect of this parameter on different grading, two different grading (Top coat index grading and binder index grading) have been used and samples were compacted at 5 various temperatures.

Keywords: Compaction Temperature, HMA, Volumetric Parameters, Marshall Method

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766 Numerical Modelling of Effective Diffusivity in Bone Tissue Engineering

Authors: Ayesha Sohail, Khadija Maqbool, Anila Asif, Haroon Ahmad

Abstract:

These days, the field of tissue engineering is getting serious attention due to its usefulness. Bone tissue engineering helps to address and sort-out the critical sized and non-healing orthopedic problems by the creation of manmade bone tissue. We will design and validate an efficient numerical model, which will simulate the effective diffusivity in bone tissue engineering. Our numerical model will be based on the finite element analysis of the diffusion-reaction equations. It will have the ability to optimize the diffusivity, even at multi-scale, with the variation of time. It will also have a special feature “parametric sweep”, with which we will be able to predict the oxygen, glucose and cell density dynamics, more accurately. We will fix these problems by modifying the governing equations, by selecting appropriate spatio-temporal finite element schemes and by transient analysis.

Keywords: Bone tissue engineering, Transient Analysis, Scaffolds, fabrication techniques.

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765 Sewage Sludge Management in Egypt: Current Status and Perspectives towards a Sustainable Agricultural Use

Authors: M. Ghazy, T. Dockhorn, N. Dichtl

Abstract:

The present disposal routes of sewage sludge represent a critical environmental issue in Egypt. Recently, there has been an increasing concern about sewage sludge management due to the environmental risks, which resulted from the fast expansion of wastewater treatment plants without equal attention in dealing with the produced sludge. This paper discusses the current situation of sewage sludge management in Egypt presenting a brief overview of the existing wastewater treatment plants, sludge production and characteristics as well as options of beneficial use and potential demand of sewage sludge under Egyptian conditions. The characteristics of sewage sludge are discussed considering the results of own sampling and analysis as well as previous studies. Furthermore, alternative treatment scenarios for sewage sludge, which have been recently developed in Egypt, are discussed and perspectives for a sustainable agricultural use are outlined.

Keywords: Beneficial use, Egypt, Monetary value, Stabilization processes, Sewage sludge, Sludge management

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764 The Hybrid Dimming Control System for Solar Charging Robot

Authors: A. Won-Yong Chae, B. Hyung-Nam Kim, C. Kyoung-Jun Lee, D. Hee-Je Kim

Abstract:

The renewable energy has been attracting attention as a new alternative energy due to the problem of environmental pollution and resource depletion. In particular, daylighting and PV system are regarded as the solutions. In this paper, the hybrid dimming control system supplied by solar cell and daylighting system was designed. Daylighting system is main source and PV system is spare source. PV system operates the LED lamp which supports daylighting system because daylighting system is unstable due to the variation of irradiance. In addition, PV system has a role charging batteries. Battery charging has a benefit that PV system operate LED lamp in the bad weather. However, LED lamp always can`t turn on that-s why dimming control system was designed. In particular, the solar charging robot was designed to check the interior irradiance intensity. These systems and the application of the solar charging robot are expected to contribute developing alternative energy in the near future.

Keywords: Daylighting system, PV system, LED lamp, Suntracking robot.

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763 Optimization of a Four-Lobed Swirl Pipe for Clean-In-Place Procedures

Authors: Guozhen Li, Philip Hall, Nick Miles, Tao Wu

Abstract:

This paper presents a numerical investigation of two horizontally mounted four-lobed swirl pipes in terms of swirl induction effectiveness into flows passing through them. The swirl flows induced by the two swirl pipes have the potential to improve the efficiency of Clean-In-Place procedures in a closed processing system by local intensification of hydrodynamic impact on the internal pipe surface. Pressure losses, swirl development within the two swirl pipe, swirl induction effectiveness, swirl decay and wall shear stress variation downstream of two swirl pipes are analyzed and compared. It was found that a shorter length of swirl inducing pipe used in joint with transition pipes is more effective in swirl induction than when a longer one is used, in that it has a less constraint to the induced swirl and results in slightly higher swirl intensity just downstream of it with the expense of a smaller pressure loss. The wall shear stress downstream of the shorter swirl pipe is also slightly larger than that downstream of the longer swirl pipe due to the slightly higher swirl intensity induced by the shorter swirl pipe. The advantage of the shorter swirl pipe in terms of swirl induction is more significant in flows with a larger Reynolds Number.

Keywords: Swirl pipe, swirl effectiveness, CFD, wall shear stress, swirl intensity.

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762 Investigation of the Flow Characteristics in a Catalytic Muffler with Perforated Inlet Cone

Authors: Gyo Woo Lee, Man Young Kim

Abstract:

Emission regulations for diesel engines are being strengthened and it is impossible to meet the standards without exhaust after-treatment systems. Lack of the space in many diesel vehicles, however, make it difficult to design and install stand-alone catalytic converters such as DOC, DPF, and SCR in the vehicle exhaust systems. Accordingly, those have been installed inside the muffler to save the space, and referred to the catalytic muffler. However, that has complex internal structure with perforated plate and pipe for noise and monolithic catalyst for emission reduction. For this reason, flow uniformity and pressure drop, which affect efficiency of catalyst and engine performance, respectively, should be examined when the catalytic muffler is designed. In this work, therefore, the flow uniformity and pressure drop to improve the performance of the catalytic converter and the engine have been numerically investigated by changing various design parameters such as inlet shape, porosity, and outlet shape of the muffler using the three-dimensional turbulent flow of the incompressible, non-reacting, and steady state inside the catalytic muffler. Finally, it can be found that the shape, in which the muffler has perforated pipe inside the inlet part, has higher uniformity index and lower pressure drop than others considered in this work.

Keywords: Catalytic muffler, Perforated inlet cone, Catalysts, Perforated pipe, Flow uniformity, Pressure drop.

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761 Determinants and Perspectives of an Accounting Career. Empirical Evidence on Students' Perceptions

Authors: Maria Mădălina Gîrbină, Nadia Albu, Cătălin Nicolae Albu

Abstract:

This study realizes an empirical investigation of main factors to develop an accounting career, stereotypes on accountants and accounting and perceptions on future career path for a sample of master students in accounting. The research provides some insight into what master students consider when choosing their future career paths. The most important two reasons chosen by students were “career opportunities" and “future earnings. They see accounting as structured, governed by conformity, requiring skills in working with numbers, monotonous, accurate, more efficient than effective but also absorbing, interesting and involving a certain degree of novelty. Although these students plan to start their careers in a multinational or accounting/audit firm, most of those plan to leave after five years. It resulted that women value more flexibility and time requiring special attention in retention policies practiced by firms.

Keywords: Accounting career, students' perception, stereotypes.

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760 An Evaluation of a Psychotherapeutic Service for Engineering Students: The Role of Race, Gender and Language

Authors: Nazeema Ahmed

Abstract:

Mental health in higher education has received increasing attention over the past few decades. The high academic demands of the engineering degree, coupled with students’ mental health challenges, have led to higher education institutions offering psychotherapeutic services to students. This paper discusses an evaluation of the psychotherapy service at the University of Cape Town. The aim was to determine (i) the efficacy of the service; and (ii) the impact of race, gender, and language of the therapist on the students’ therapeutic process. An online survey was sent to 109 students who attended psychotherapy. The majority expressed favorable experiences of psychotherapy, with reports of increased capacity to engage with their academic work. Most students did not experience the gender, race, or language of the psychologists to be barriers to their therapy. The findings point to a need for ongoing psychological support for students.

Keywords: Psychotherapy, efficacy, engineering, education.

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759 Exploring the Activity Fabric of an Intelligent Environment with Hierarchical Hidden Markov Theory

Authors: Chiung-Hui Chen

Abstract:

The Internet of Things (IoT) was designed for widespread convenience. With the smart tag and the sensing network, a large quantity of dynamic information is immediately presented in the IoT. Through the internal communication and interaction, meaningful objects provide real-time services for users. Therefore, the service with appropriate decision-making has become an essential issue. Based on the science of human behavior, this study employed the environment model to record the time sequences and locations of different behaviors and adopted the probability module of the hierarchical Hidden Markov Model for the inference. The statistical analysis was conducted to achieve the following objectives: First, define user behaviors and predict the user behavior routes with the environment model to analyze user purposes. Second, construct the hierarchical Hidden Markov Model according to the logic framework, and establish the sequential intensity among behaviors to get acquainted with the use and activity fabric of the intelligent environment. Third, establish the intensity of the relation between the probability of objects’ being used and the objects. The indicator can describe the possible limitations of the mechanism. As the process is recorded in the information of the system created in this study, these data can be reused to adjust the procedure of intelligent design services.

Keywords: Behavior, big data, hierarchical Hidden Markov Model, intelligent object.

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758 Numerical Study on Parametrical Design of Long Shrouded Contra-Rotating Propulsion System in Hovering

Authors: Chao. Huo, Roger. Barènes, Jérémie. Gressier, Gilles.Grondin

Abstract:

The parametrical study of Shrouded Contra-rotating Rotor was done in this paper based on 2D axisymmetric simulations. The calculations were made with an actuator disk as double rotor model. It objects to explore and quantify the effects of different shroud geometry parameters mainly using the performance of power loading (PL), which could evaluate the whole propulsion system capability as 5 Newtontotal thrust generationfor hover demand. The numerical results show that:The increase of nozzle radius is desired but limited by the flow separation, its optimal design is around 1.15 times rotor radius, the viscosity effects greatly constraint the influence of nozzle shape, the divergent angle around 10.5° performs best for chosen nozzle length;The parameters of inlet such as leading edge curvature, radius and internal shape do not affect thrust great but play an important role in pressure distribution which could produce most part of shroud thrust, they should be chosen according to the reduction of adverse pressure gradients to reduce the risk of boundary separation.

Keywords: Axisymmetric simulation, parametrical design, power loading, Shrouded Contra-Rotating Rotor.

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757 Elimination Noise by Adaptive Wavelet Threshold

Authors: Iman Elyasi, Sadegh Zarmehi

Abstract:

Due to some reasons, observed images are degraded which are mainly caused by noise. Recently image denoising using the wavelet transform has been attracting much attention. Waveletbased approach provides a particularly useful method for image denoising when the preservation of edges in the scene is of importance because the local adaptivity is based explicitly on the values of the wavelet detail coefficients. In this paper, we propose several methods of noise removal from degraded images with Gaussian noise by using adaptive wavelet threshold (Bayes Shrink, Modified Bayes Shrink and Normal Shrink). The proposed thresholds are simple and adaptive to each subband because the parameters required for estimating the threshold depend on subband data. Experimental results show that the proposed thresholds remove noise significantly and preserve the edges in the scene.

Keywords: Image denoising, Bayes Shrink, Modified Bayes Shrink, Normal Shrink.

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756 Effect of Geometrical Parameters on Natural Frequencies of FGM Cylindrical shell with Holes Under Various Boundary Conditions

Authors: Mostafa Ghayour, Mohammad Sadegh Golabi

Abstract:

In the recent years, functionally gradient materials (FGMs) have gained considerable attention in the high temperature environment applications. In this paper, free vibration of thin functionally graded cylindrical shell with hole composed of stainless steel and zirconia is studied. The mechanical properties vary smoothly and continuously from one surface to the other according to a volume fraction power-law distribution. The Influence of shell geometrical parameters, variations of volume fractions and boundary conditions on natural frequency is considered. The equations of motion are based on strains-displacement relations from Love-s shell theory and Rayleigh method. The results have been obtained for natural frequencies of cylindrical shell with holes for different shape, number and location in this paper.

Keywords: Functionally gradient material, Vibration, various boundary conditions, cylindrical shells.

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755 A Novel Framework for User-Friendly Ontology-Mediated Access to Relational Databases

Authors: Efthymios Chondrogiannis, Vassiliki Andronikou, Efstathios Karanastasis, Theodora Varvarigou

Abstract:

A large amount of data is typically stored in relational databases (DB). The latter can efficiently handle user queries which intend to elicit the appropriate information from data sources. However, direct access and use of this data requires the end users to have an adequate technical background, while they should also cope with the internal data structure and values presented. Consequently the information retrieval is a quite difficult process even for IT or DB experts, taking into account the limited contributions of relational databases from the conceptual point of view. Ontologies enable users to formally describe a domain of knowledge in terms of concepts and relations among them and hence they can be used for unambiguously specifying the information captured by the relational database. However, accessing information residing in a database using ontologies is feasible, provided that the users are keen on using semantic web technologies. For enabling users form different disciplines to retrieve the appropriate data, the design of a Graphical User Interface is necessary. In this work, we will present an interactive, ontology-based, semantically enable web tool that can be used for information retrieval purposes. The tool is totally based on the ontological representation of underlying database schema while it provides a user friendly environment through which the users can graphically form and execute their queries.

Keywords: Ontologies, Relational Databases, SPARQL, Web Interface.

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