Search results for: Fire performance

Authors: Changho Han, Jaemin Lee, Li Hua, Seokkwon Jeong

Abstract:

Design of membership function ranges in fuzzy logic control (FLC) is presented for robust control of a variable speed refrigeration system (VSRS). The criterion values of the membership function ranges can be carried out from the static experimental data, and two different values are offered to compare control performance. Some simulations and real experiments for the VSRS were conducted to verify the validity of the designed membership functions. The experimental results showed good agreement with the simulation results, and the error change rate and its sampling time strongly affected the control performance at transient state of the VSRS.

Keywords: Variable speed refrigeration system, Fuzzy logic control, membership function range, control performance.

Procedia APA BibTeX Chicago EndNote Harvard JSON MLA RIS XML ISO 690 PDF Downloads 963

Authors: Houda Abadlia, Nadia Smairi, Khaled Ghedira

Abstract:

Multiobjective Particle Swarm Optimization (MOPSO) has shown an effective performance for solving test functions and real-world optimization problems. However, this method has a premature convergence problem, which may lead to lack of diversity. In order to improve its performance, this paper presents a hybrid approach which embedded the MOPSO into the island model and integrated a local search technique, Variable Neighborhood Search, to enhance the diversity into the swarm. Experiments on two series of test functions have shown the effectiveness of the proposed approach. A comparison with other evolutionary algorithms shows that the proposed approach presented a good performance in solving multiobjective optimization problems.

Keywords: Particle swarm optimization, migration, variable neighborhood search, multiobjective optimization.

Procedia APA BibTeX Chicago EndNote Harvard JSON MLA RIS XML ISO 690 PDF Downloads 809

Authors: Chee Peng Lim, Wei Yee Goh

Abstract:

In this paper, the application of multiple Elman neural networks to time series data regression problems is studied. An ensemble of Elman networks is formed by boosting to enhance the performance of the individual networks. A modified version of the AdaBoost algorithm is employed to integrate the predictions from multiple networks. Two benchmark time series data sets, i.e., the Sunspot and Box-Jenkins gas furnace problems, are used to assess the effectiveness of the proposed system. The simulation results reveal that an ensemble of boosted Elman networks can achieve a higher degree of generalization as well as performance than that of the individual networks. The results are compared with those from other learning systems, and implications of the performance are discussed.

Keywords: AdaBoost, Elman network, neural network ensemble, time series regression.

Procedia APA BibTeX Chicago EndNote Harvard JSON MLA RIS XML ISO 690 PDF Downloads 1691

Authors: Young Kwon Yang, In Sung Kang, Jung Ha Hwang, Jin Chul Park

Abstract:

The present study is a foundational study for performance improvements on isolation wards to prevent proliferation of secondary infection of infectious diseases such as SARS, H1N1, and MERS inside hospitals. Accordingly, the present study conducted an analysis of the effect of sealing mechanisms and filling of openings on ensuring air tightness performance in isolation wards as well as simulation on air currents in improved isolation wards. The study method is as follows. First, previous studies on aerial infection type and mechanism were reviewed, and the review results were utilized as basic data of analysis on simulation of air current. Second, national and international legislations and regulations in relation to isolation wards as well as case studies on developed nations were investigated in order to identify the problems in isolation wards in Korea and improvement plans. Third, construction and facility plans were compared and analyzed between general and isolation wards focusing on large general hospitals in Korea, thereby conducting comparison and analysis on the performance and effects of air-tightness of general and isolation wards through CFD simulations. The study results showed that isolation wards had better air-tightness performance than that of general wards.

Keywords: AII Room, air-borne infection, CFD, computational fluid dynamics.

Procedia APA BibTeX Chicago EndNote Harvard JSON MLA RIS XML ISO 690 PDF Downloads 1522

Authors: A. Bouabid, B. Bielenberg, S. Ainane, N. Pasha

Abstract:

In this paper, a team of faculty members of the Petroleum Institute in Abu Dhabi, UAE representing six different courses across General Engineering (ENGR), Communication (COMM), and Design (STPS) worked together to establish a clear developmental progression of learning outcomes and performance indicators for targeted knowledge, areas of competency, and skills for the first three semesters of the Bachelor of Sciences in Engineering curriculum. The sequences of courses studied in this project were ENGR/COMM, COMM/STPS, and ENGR/STPS. For each course’s nine areas of knowledge, competency, and skills, the research team reviewed the existing learning outcomes and related performance indicators with a focus on identifying linkages across disciplines as well as within the courses of a discipline. The team reviewed existing performance indicators for developmental progression from semester to semester for same discipline related courses (vertical alignment) and for different discipline courses within the same semester (horizontal alignment). The results of this work have led to recommendations for modifications of the initial indicators when incoherence was identified, and/or for new indicators based on best practices (identified through literature searches) when gaps were identified. It also led to recommendations for modifications of the level of emphasis within each course to ensure developmental progression. The exercise has led to a revised Sequence Performance Indicator Mapping for the knowledge, skills, and competencies across the six core courses.

Keywords: Curriculum alignment, horizontal and vertical progression, performance indicators, skill level.

Procedia APA BibTeX Chicago EndNote Harvard JSON MLA RIS XML ISO 690 PDF Downloads 838

Authors: Cheng-Suan Lee, Khong Neng Choong, So Gean Koh, Chee Onn Chow, Mazlan Abbas

Abstract:

Voice over Internet Protocol (VoIP) application or commonly known as softphone has been developing an increasingly large market in today-s telecommunication world and the trend is expected to continue with the enhancement of additional features. This includes leveraging on the existing presence services, location and contextual information to enable more ubiquitous and seamless communications. In this paper, we discuss the concept of seamless session transfer for real-time application such as VoIP and IPTV, and our prototype implementation of such concept on a selected open source VoIP application. The first part of this paper is about conducting performance evaluation and assessments across some commonly found open source VoIP applications that are Ekiga, Kphone, Linphone and Twinkle so as to identify one of them for implementing our design of seamless session transfer. Subjective testing has been carried out to evaluate the audio performance on these VoIP applications and rank them according to their Mean Opinion Score (MOS) results. The second part of this paper is to discuss on the performance evaluations of our prototype implementation of session transfer using Linphone.

Keywords: audio codec, softphone, session transfer.

Procedia APA BibTeX Chicago EndNote Harvard JSON MLA RIS XML ISO 690 PDF Downloads 1686

Authors: K. Saravanan, R. Anita

Abstract:

Flexible AC Transmission Systems (FACTS) is granting a new group of advanced power electronic devices emerging for enhancement of the power system performance. Unified Power Flow Controller (UPFC) is a recent version of FACTS devices for power system applications. The back-up energy supply system incorporated with UPFC is providing a complete control of real and reactive power at the same time and hence is competent to improve the performance of an electrical power system. In this article, backup energy supply unit such as superconducting magnetic energy storage (SMES) is integrated with UPFC. In addition, comparative exploration of UPFC–battery, UPFC–UC and UPFC–SMES performance is evaluated through the vibrant simulation by using MATLAB/Simulink software.

Keywords: Power system, FACTS, UPFC, DC-DC chopper, battery, UC, SMES.

Procedia APA BibTeX Chicago EndNote Harvard JSON MLA RIS XML ISO 690 PDF Downloads 1956

Authors: Wen-Pai Wang

Abstract:

The growing influence of service industries has prompted greater attention being paid to service operations management. However, service managers often have difficulty articulating the veritable effects of their service innovation. Especially, the performance evaluation process of service innovation problems generally involves uncertain and imprecise data. This paper presents a 2-tuple fuzzy linguistic computing approach to dealing with heterogeneous information and information loss problems while the processes of subjective evaluation integration. The proposed method based on group decision-making scenario to assist business managers in measuring performance of service innovation manipulates the heterogeneity integration processes and avoids the information loss effectively.

Keywords: Group decision-making, Heterogeneity, Linguisticcomputing, Multi-criteria, Service innovation

Procedia APA BibTeX Chicago EndNote Harvard JSON MLA RIS XML ISO 690 PDF Downloads 1570

Authors: Milan Paudel, Fook Fah Yap, Anil K. Bastola

Abstract:

The difficulties in riding small wheel bicycles and their lesser stability have been perceived for a long time. Although small wheel bicycles are designed using the similar approach and guidelines that have worked well for big wheel bicycles, the performance of the big wheelers and the smaller wheelers are markedly different. Since both the big wheelers and small wheelers have same fundamental geometry, most blame the small wheel for this discrepancy in the performance. This paper reviews existing guidelines for bicycle design, especially the front steering geometry for the bicycle, and provides a systematic and quantitative analysis of different wheel sized bicycles. A validated mathematical model has been used as a tool to assess the dynamic performance of the bicycles in term of their self-stability. The results obtained were found to corroborate the subjective perception of cyclists for small wheel bicycles. The current approach for small wheel bicycle design requires higher speed to be self-stable. However, it was found that increasing the headtube angle and selecting a proper trail could improve the dynamic performance of small wheel bicycles. A range of parameters for front steering geometry has been identified for small wheel bicycles that have comparable stability as big wheel bicycles. Interestingly, most of the identified geometries are found to be beyond the ISO recommended range and seem to counter the current approach of small wheel bicycle design. Therefore, it was successfully shown that the guidelines for big wheelers do not translate directly to small wheelers, but careful selection of the front geometry could make small wheel bicycles as stable as big wheel bicycles.

Keywords: Big wheel bicycle, design approach, ISO requirements, small wheel bicycle, stability and performance.

Procedia APA BibTeX Chicago EndNote Harvard JSON MLA RIS XML ISO 690 PDF Downloads 849

Authors: M. Ben Slimene, M.-S. Ouali

Abstract:

Asset management of urban infrastructures faces a multitude of challenges that need to be overcome to obtain a reliable measurement of performances. Predicting the performance of slowly aging systems is one of those challenges, which helps the asset manager to investigate specific failure modes and to undertake the appropriate maintenance and rehabilitation interventions to avoid catastrophic failures as well as to optimize the maintenance costs. This article presents a methodology for modeling the deterioration of slowly degrading assets based on an operating history. It consists of extracting degradation profiles by grouping together assets that exhibit similar degradation sequences using an unsupervised classification technique derived from artificial intelligence. The obtained clusters are used to build the performance prediction models. This methodology is applied to a sample of a stormwater drainage culvert dataset.

Keywords: Artificial intelligence, clustering, culvert, regression model, slow degradation.

Procedia APA BibTeX Chicago EndNote Harvard JSON MLA RIS XML ISO 690 PDF Downloads 455

Authors: Mahmoud Miri, Soliman Maramaee

Abstract:

Because of architectural condition and structure application, sometimes mass source and stiffness source are not coincidence, and the structure is irregular. The structure is also might be asymmetric as an asymmetric bracing in plan which leads to unbalance distribution of stiffness or because of unbalance distribution of the mass. Both condition lead to eccentricity and torsion in the structure. The deficiency of ordinary code to evaluate the performance of steel structures against earthquake has been caused designing based on performance level or capacity spectrum be used. By using the mentioned methods it is possible to design a structure that its behavior against different earthquakes be predictive. In this article 5- story buildings with different percentage of asymmetric which is because of stiffness changes and kind of bracing (x and chevron bracing) have been designed. The static and dynamic nonlinear analysis under three acceleration recording has been done. Finally performance level of the structure has been evaluated.

Keywords: Asymmetric, irregular, seismic analysis, torsion.

Procedia APA BibTeX Chicago EndNote Harvard JSON MLA RIS XML ISO 690 PDF Downloads 1638

Authors: Yun Mi, Ko, Hye Jung, Joo

Abstract:

This study develops a relation to explore the factors influencing management and technology capabilities in strategic alliances. Alliances between firms are recognizing increasingly popular as a vehicle to create and extract greater value from the market. Firm’s alliance can be described as the collaborative problem solving process to solve problems jointly. This study starts from research questions what factors of firm’s management and technology characteristics affect performance of firms which are formed alliances. In this study, we investigated the effect of strategic alliances on company performance. That is, we try to identify whether firms made an alliance with other organizations are differed by characteristics of management and technology. And we test that alliance type and alliance experiences moderate the relationship between firm’s capabilities and its performance. We employ problem-solving perspective and resource-based view perspective to shed light on this research questions. The empirical work is based on the Survey of Business Activities conducted from2006 to 2008 by Statistics Korea. We verify correlations between to point out that these results contribute new empirical evidence on the effect of strategic alliances on company performance.

Keywords: Problem solving process, strategic alliance.

Procedia APA BibTeX Chicago EndNote Harvard JSON MLA RIS XML ISO 690 PDF Downloads 1544

Authors: Ahmed A. Hassan, Hassan I. Ali, Abdallah A. Salum, Asia M. Kassim, Yussuf N. Elmoge, Ali A. Amour

Abstract:

The purpose of this study was to investigate the performance of chemistry in Zanzibar Secondary Schools. It was conducted in all regions of Zanzibar in public and private secondary schools and Ministry of Education officials. The objective of the study included finding out causes of poor performance in chemistry. Views, opinions, and suggestions of teachers and students to improve performance of chemistry and a descriptive survey was adopted for the study. 45 teachers and 200 students were randomly sampled from 15 secondary schools in Zanzibar and ten Ministry of Education officials were purposively sampled for the study. Questionnaires and open-ended interview schedules were the main instruments used in obtaining relevant data from respondents. Data collected from the field was analyzed both qualitatively and quantitatively. Qualitative analysis involved content analysis of the responses obtained through interviews and quantitative analysis involved generation of tables, frequencies and percentages. The results revealed that there were shortages of trained teachers, lack of proficiency in the language of instruction (English) and major facilities like laboratories and books. These led to poor delivery of subject matter and consequently resulting in poor performance. Based on the findings, this study recommends that provision of trained, competent, and effective teachers as vital aspects to be considered. Government through Ministry of Education should put effort to stalk libraries and equip laboratories with modern books and instruments. In addition, the ministry should strengthen teachers’ training and encourage use of instructional media in class and make conducive learning environment to both teachers and students.

Keywords: Zanzibar, secondary schools, chemistry, science, performance and factors.

Procedia APA BibTeX Chicago EndNote Harvard JSON MLA RIS XML ISO 690 PDF Downloads 7290

Authors: Subrata Das, Sisir Kumar Guha

Abstract:

The objective of the present paper is to theoretically investigate the steady-state performance characteristics of journal bearing of finite width, operating with micropolar lubricant in a turbulent regime. In this analysis, the turbulent shear stress coefficients are used based on the Constantinescu’s turbulent model suggested by Taylor and Dowson with the assumption of parallel and inertia-less flow. The numerical solution of the modified Reynolds equation has yielded the distribution of film pressure which determines the static performance characteristics in terms of load capacity, attitude angle, end flow rate and frictional parameter at various values of eccentricity ratio, non-dimensional characteristics length, coupling number and Reynolds number.

Keywords: Hydrodynamic lubrication, steady-state, micropolar lubricant, turbulent.

Procedia APA BibTeX Chicago EndNote Harvard JSON MLA RIS XML ISO 690 PDF Downloads 2748

Authors: Consalva J. Msigwa, Beda J. Kundy, Bakari M. M. Mwinyiwiwa,

Abstract:

This paper presents a method for obtaining the desired reference current for Voltage Source Converter (VSC) of the Shunt Active Power Filter (SAPF) using Synchronous Reference Frame Theory. The method relies on the performance of the Proportional-Integral (PI) controller for obtaining the best control performance of the SAPF. To improve the performance of the PI controller, the feedback path to the integral term is introduced to compensate the winding up phenomenon due to integrator. Using Reference Frame Transformation, reference signals are transformed from a - b - c stationery frame to 0 - d - q rotating frame. Using the PI controller, the reference signals in the 0 - d - q rotating frame are controlled to get the desired reference signals for the Pulse Width Modulation. The synchronizer, the Phase Locked Loop (PLL) with PI filter is used for synchronization, with much emphasis on minimizing delays. The system performance is examined with Shunt Active Power Filter simulation model.

Keywords: Phase Locked Loop (PLL), Voltage Source Converter (VSC), Shunt Active Power Filter (SAPF), PI, Pulse Width Modulation (PWM)

Procedia APA BibTeX Chicago EndNote Harvard JSON MLA RIS XML ISO 690 PDF Downloads 3565

Authors: Osama H. Ghazal

Abstract:

The intension in this work is to investigate the effect of different fuels type on engine performance for different engine speed. Brake Power, Brake Torque, and specific fuel consumption were calculated and presented to show the effect of varying fuel type on them for all cases considered. A special program used to carry out the calculations. A simulation model for one-cylinder spark ignition engine has been built and calculated.

The analysis of the results shows that for methanol the power increases about 30% at 1000 rpm and 16% at 6000 rpm comparing with methane. For the same compared fuels the increment in fuel consumption is about 100% at 1000 rpm and 115% at 6000 rpm. The increment in brake thermal efficiency for gasoline is around 11% comparing with methane at 1000 rpm and 7% for methanol comparing with methane at 4000 rpm.

Keywords: Natural gas fuel, spark ignition engines, performance, engine simulation.

Procedia APA BibTeX Chicago EndNote Harvard JSON MLA RIS XML ISO 690 PDF Downloads 3002

Authors: Sanjay Singh, M Sathish Kumar, H. S Mruthyunjaya

Abstract:

Multicarrier transmission system such as Orthogonal Frequency Division Multiplexing (OFDM) is a promising technique for high bit rate transmission in wireless communication system. OFDM is a spectrally efficient modulation technique that can achieve high speed data transmission over multipath fading channels without the need for powerful equalization techniques. However the price paid for this high spectral efficiency and less intensive equalization is low power efficiency. OFDM signals are very sensitive to nonlinear effects due to the high Peak-to-Average Power Ratio (PAPR), which leads to the power inefficiency in the RF section of the transmitter. This paper investigates the effect of PAPR reduction on the performance parameter of multicarrier communication system. Performance parameters considered are power consumption of Power Amplifier (PA) and Digital-to-Analog Converter (DAC), power amplifier efficiency, SNR of DAC and BER performance of the system. From our analysis it is found that irrespective of PAPR reduction technique being employed, the power consumption of PA and DAC reduces and power amplifier efficiency increases due to reduction in PAPR. Moreover, it has been shown that for a given BER performance the requirement of Input-Backoff (IBO) reduces with reduction in PAPR.

Keywords: BER, Crest Factor (CF), Digital-to-Analog Converter(DAC), Input-Backoff (IBO), Orthogonal Frequency Division Multiplexing(OFDM), Peak-to-Average Power Ratio (PAPR), PowerAmplifier efficiency, SNR

Procedia APA BibTeX Chicago EndNote Harvard JSON MLA RIS XML ISO 690 PDF Downloads 3286

Authors: Chien-Yeh Hsu, Yuan-Ching Chiang, Zi-Jie Chien, Sih-Li Chen

Abstract:

In this study, a field experiment and performance analysis of air-tunnel heat exchanger integrated with water-filled raft foundation of residential building were performed. In order to obtain better performance, conventional applications of air-tunnel inevitably have high initial cost or issues about insufficient installation space. To improve the feasibility of air tunnel heat exchanger in high-density housing, an integrated system consisting of air pipes immersed in the water-filled raft foundation was presented, taking advantage of immense amount of water and relatively stable temperature in raft foundation of building. The foundation-integrated air tunnel was applied to a residential building located in Yilan, Taiwan, and its thermal performance was measured in the field experiment. The results indicated that the cooling potential of integrated system was close to the potential of soil-based EAHE at 2 m depth or deeper. An analytical model based on thermal resistance method was validated by measurement results, and was used to carry out the dimensioning of foundation-integrated air tunnel. The discrepancies between calculated value and measured data were less than 2.7%. In addition, the return-on-investment with regard to thermal performance and economics of the application was evaluated. Because the installation for air tunnel is scheduled in the building foundation construction, the utilization of integrated system spends less construction cost compare to the conventional earth-air tunnel.

Keywords: Air tunnel, ground heat exchanger, raft foundation, residential building.

Procedia APA BibTeX Chicago EndNote Harvard JSON MLA RIS XML ISO 690 PDF Downloads 1421

Authors: Yassir M. Abbas, Mohammad Iqbal Khan, Galal Fares

Abstract:

In the present work, the structural responses of 12 ultra-high-performance concrete (UHPC) beams to four-point loading conditions were experimentally and analytically studied. The inclusion of a fibrous system in the UHPC material increased its compressive and flexural strengths by 31.5% and 237.8%, respectively. Based on the analysis of the load-deflection curves of UHPC beams, it was found that UHPC beams with a low reinforcement ratio are prone to sudden brittle failure. This failure behavior was changed, however, to a ductile one in beams with medium to high ratios. The implication is that improving UHPC beam tensile reinforcement could result in a higher level of safety. More reinforcement bars also enabled the load-deflection behavior to be improved, particularly after yielding.

Keywords: Ultra-high-performance concrete, moment capacity, RC beams, hybrid fiber, ductility.

Procedia APA BibTeX Chicago EndNote Harvard JSON MLA RIS XML ISO 690 PDF Downloads 133

Authors: Fernando Seabra, Giulia P. Flores, Karolina C. Gomes

Abstract:

Trade liberalizations measures, as import tariff cuts, are not a sufficient trigger for trade growth. Given that price margins are narrow, traders and cargo operators tend to opt out of markets where the process of goods clearance is slow and costly. Excess paperwork and slow customs dispatch not only lead to institutional breakdowns and corruption but also to increasing transaction cost and trade constraints. The objective of this paper is, therefore, two-fold: First, to evaluate the relationship between institutional and infrastructural performance indexes and trade growth in container throughput; and, second, to investigate the causes for differences in container demurrage and detention fees in Latin American countries (using other emerging countries as benchmarking). The analysis is focused on manufactured goods, typically transported by containers. Institutional and infrastructure bottlenecks and, therefore, the country logistics efficiency – measured by the Logistics Performance Index (LPI, World Bank-WB) – are compared with other indexes, such as the Doing Business index (WB) and the Corruption Perception Index (Transparency International). The main results based on the comparison between Latin American countries and the others emerging countries point out in that the growth in containers trade is directly related to LPI performance. It has also been found that the main hypothesis is valid as aspects that more specifically identify trade facilitation and corruption are significant drivers of logistics performance. The exam of port efficiency (demurrage and detention fees) has demonstrated that not necessarily higher level of efficiency is related to lower charges; however, reductions in fees have been more significant within non-Latin American emerging countries.

Keywords: Container throughput, logistics performance, corruption, Latin America.

Procedia APA BibTeX Chicago EndNote Harvard JSON MLA RIS XML ISO 690 PDF Downloads 1561

Authors: Jin-Ho Bae, Yong-Tae Kim, S K Deb Nath, Seo-Ik Kang, Sung-Gaun Kim

Abstract:

Reno-pin contact test is a method that is controlled by DC motor used to characterize electronic chips. This method is used in electronic and telecommunication devices. A new electric performance testing system is developed in which the testing method is controlled by using Piezoelectric Transducer (PZT) instead of DC motor which reduces vibration and noise. The vertical displacement of the Reno-pin is very short in the Reno-pin contact testing system. Now using a flexible guide in the new Reno-pin contact system, the vertical movement of the Reno-pin is increased many times of the existing Reno-pin contact testing method using DC motor. Using the present electric performance testing system with a flexible hinge and PZT instead of DC motor, manufacturing of electronic chips are able to characterize chips with low cost and high speed.

Keywords: PZT Actuator, Chip test, Mechanical amplifier

Procedia APA BibTeX Chicago EndNote Harvard JSON MLA RIS XML ISO 690 PDF Downloads 1993

Authors: M. Ibrahim Sadik, Toril Myrtveit

Abstract:

The aim of this investigation is to study the performance of the new generation of the PVD coated grade and to map the influence of cutting conditions on the tool life in milling of ADI (Austempered Ductile Iron). The results show that chipping is the main wear mechanism which determines the tool life in dry condition and notch wear in wet condition for this application. This due to the different stress mechanisms and preexisting cracks in the coating. The wear development shows clearly that the new PVD coating (C20) has the best ability to delay the chipping growth. It was also found that a high content of Al in the new coating (C20) was especially favorable compared to a TiAlN multilayer with lower Al content (C30) or CVD coating. This is due to fine grains and low compressive stress level in the coating which increase the coating ability to withstand the mechanical and thermal impact. It was also found that the use of coolant decreases the tool life with 70-80% compare to dry milling.

Keywords: Austempered Ductile Iron (ADI), coating, chipping, milling, tool performance.

Procedia APA BibTeX Chicago EndNote Harvard JSON MLA RIS XML ISO 690 PDF Downloads 1934

Authors: Hyun-Jun Shin, Jae-Jeong Kim, Hyoung-Kyu Song

Abstract:

In broadcasting and cellular system, a cooperative  scheme is proposed for the improvement of performance of bit error  rate. Up to date, the coverage of broadcasting system coexists with the  coverage of cellular system. Therefore each user in a cellular coverage  is frequently involved in a broadcasting coverage. The proposed  cooperative scheme is derived from the shared areas. The users receive  signals from both broadcasting station and cellular station. The  proposed scheme selects a cellular base station of a worse channel to  achieve better performance of bit error rate in cooperation. The  performance of the proposed scheme is evaluated in fading channel.

Keywords: Cooperative communication, diversity, STBC, CDD, channel condition, broadcasting system, cellular system.

Procedia APA BibTeX Chicago EndNote Harvard JSON MLA RIS XML ISO 690 PDF Downloads 1736

Authors: Ashish Goswami, Rakesh Sharma

Abstract:

In this paper, LDPC Codes based on defected fullerene graphs have been generated. And it is found that the codes generated are fast in encoding and better in terms of error performance on AWGN Channel.

Keywords: LDPC Codes, Fullerene Graphs, Defected Fullerene Graphs.

Procedia APA BibTeX Chicago EndNote Harvard JSON MLA RIS XML ISO 690 PDF Downloads 1768

Authors: Sang Su Lee, Sang Woo Lee, Yong Sung Jeon, Ki Young Kim

Abstract:

IPsec protocol[1] is a set of security extensions developed by the IETF and it provides privacy and authentication services at the IP layer by using modern cryptography. In this paper, we describe both of H/W and S/W architectures of our router system, SRS-10. The system is designed to support high performance routing and IPsec VPN. Especially, we used Cavium-s CN2560 processor to implement IPsec processing in inline-mode.

Keywords: IP, router, VPN, IPsec.

Procedia APA BibTeX Chicago EndNote Harvard JSON MLA RIS XML ISO 690 PDF Downloads 2034

Authors: A. Al-Rashidi, A. El-Hamalawi

Abstract:

In this paper, a performance study was conducted to investigate single and dual-axis PV systems to generate electricity in five different sites in Kuwait. Relevant data were obtained by using two sources for validation purposes. A commercial software, PVsyst, was used to analyse the data, such as metrological data and other input parameters, and compute the performance parameters such as capacity factor (CF) and final yield (YF). The results indicated that single and dual-axis PV systems would be very beneficial to electricity generation in Kuwait as an alternative source to conventional power plants, especially with the increased demand over time. The ranges were also found to be competitive in comparison to leading countries using similar systems. A significant increase in CF and YF values around 24% and 28.8% was achieved related to the use of single and dual systems, respectively.

Keywords: Single-axis and dual-axis photovoltaic systems, capacity factor, final yield, renewable energy, Kuwait.

Procedia APA BibTeX Chicago EndNote Harvard JSON MLA RIS XML ISO 690 PDF Downloads 1556

Authors: Wen W. Zhang, Qian Chen, Bei B. Zhou, Wei J. He

Abstract:

Over the past years, the EMCCD has had a profound influence on photon starved imaging applications relying on its unique multiplication register based on the impact ionization effect in the silicon. High signal-to-noise ratio (SNR) means high image quality. Thus, SNR improvement is important for the EMCCD. This work analyzes the SNR performance of an EMCCD with gain off and on. In each mode, simplified SNR models are established for different integration times. The SNR curves are divided into readout noise (or CIC) region and shot noise region by integration time. Theoretical SNR values comparing long frame integration and frame adding in each region are presented and discussed to figure out which method is more effective. In order to further improve the SNR performance, pixel binning is introduced into the EMCCD. The results show that pixel binning does obviously improve the SNR performance, but at the expensive of the spatial resolution.

Keywords: EMCCD, SNR improvement, pixel binning

Procedia APA BibTeX Chicago EndNote Harvard JSON MLA RIS XML ISO 690 PDF Downloads 2875

Authors: Mohammad Reza Oftadeh

Abstract:

The purpose of the article is to describe project objective structure (POS) concept that was developed on research activities and experiences about project management, Balanced Scorecard (BSC) and European Foundation Quality Management Excellence Model (EFQM Excellence Model). Furthermore, this paper tries to define a balanced, systematic, and integrated measurement approach to meet project objectives and project strategic goals based on a process-oriented model. In this paper, POS is suggested in order to measure project performance in the project life cycle. After using the POS model, the project manager can ensure in order to achieve the project objectives on the project charter. This concept can help project managers to implement integrated and balanced monitoring and control project work.

Keywords: Project objectives, project performance management, PMBOK, key performance indicators, integration management.

Procedia APA BibTeX Chicago EndNote Harvard JSON MLA RIS XML ISO 690 PDF Downloads 812

Authors: Viriyavudh Sim, Woo Young Jung

Abstract:

Performance of Basalt Fiber Reinforced Polymer (BFRP) sandwich infill panel system under diagonal compression was studied by means of numerical analysis. Furthermore, the variation of temperature was considered to affect the mechanical properties of BFRP, since their composition was based on polymeric material. Moreover, commercial finite element analysis platform ABAQUS was used to model and analyze this infill panel system. Consequently, results of the analyses show that the overall performance of BFRP panel had a 15% increase compared to that of GFRP infill panel system. However, the variation of buckling load in terms of temperature for the BFRP system showed a more sensitive nature compared to those of GFRP system.

Keywords: Basalt Fiber Reinforced Polymer, Buckling performance, numerical simulation, temperature dependent materials.

Procedia APA BibTeX Chicago EndNote Harvard JSON MLA RIS XML ISO 690 PDF Downloads 1150

Authors: Emmanuel A. Oriaifo, Noel Perera, Alan Guy, Pak. S. Leung, Kian T. Tan

Abstract:

Concerns on corrosion and effective coating protection of double hull tankers and bulk carriers in service have been raised especially in water ballast tanks (WBTs). Test protocols/methodologies specifically that which is incorporated in the International Maritime Organisation (IMO), Performance Standard for Protective Coatings for Dedicated Sea Water ballast tanks (PSPC) are being used to assess and evaluate the performance of the coatings for type approval prior to their application in WBTs. However, some of the type approved coatings may be applied as very thick films to less than ideally prepared steel substrates in the WBT. As such films experience hygrothermal cycling from operating and environmental conditions, they become embrittled which may ultimately result in cracking. This embrittlement of the coatings is identified as an undesirable feature in the PSPC but is not mentioned in the test protocols within it. There is therefore renewed industrial research aimed at understanding this issue in order to eliminate cracking and achieve the intended coating lifespan of 15 years in good condition. This paper will critically review test protocols currently used for assessing and evaluating coating performance, particularly the IMO PSPC.

Keywords: Corrosion Test, Hygrothermal Cycling, Coating Test Protocols, Water Ballast Tanks.

Procedia APA BibTeX Chicago EndNote Harvard JSON MLA RIS XML ISO 690 PDF Downloads 4221