Search results for: agronomic performance
Commenced in January 2007
Frequency: Monthly
Edition: International
Paper Count: 12910

Search results for: agronomic performance

11320 Succinonitrile Modified Polyacrylamide as a Quasi-Solid Electrolyte for an Organic Based Electrochromic Device

Authors: Benjamin Orimolade, Emily Draper

Abstract:

The interest in all solid electrochromic devices (ECD) is ongoing. This is because these devices offer realistic applications of electrochromic materials in products such as sensors, windows and energy storage devices. The use of quasi-solid (gel) electrolytes for the construction of these ECDs is attractive because of their ease of preparation, availability, low cost, improved electrochromic performance, good ionic conductivity and prevention of leakages in ECDs. Herein, we developed a gel electrolyte consisting of polyacrylamide modified with succinonitrile for an ECD containing leucine-modified naphthalene diimide (NDI-L) as electrochromic material. The amount of succinonitrile in the gel was optimized, and the structure, surface morphology, and ionic conductivity of the electrolytes were assessed using microscopic techniques and electrochemical methods. The ECD fabricated with the gel electrolyte displayed good electrochromic performance with a fast switching response of up to 10 s and outstanding stability. These results add significant insight into understanding the inter- and intra-molecular interaction in succinonitrile gel electrolytes and provide a typical practicable high-performance gel electrolyte material for solid electrochromic devices.

Keywords: electrochromic device, gel electrolytes, naphthalene diimide, succinonitrile

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11319 Performance Evaluation of Soft RoCE over 1 Gigabit Ethernet

Authors: Gurkirat Kaur, Manoj Kumar, Manju Bala

Abstract:

Ethernet is the most influential and widely used technology in the world. With the growing demand of low latency and high throughput technologies like InfiniBand and RoCE, unique features viz. RDMA (Remote Direct Memory Access) have evolved. RDMA is an effective technology which is used for reducing system load and improving performance. InfiniBand is a well known technology which provides high-bandwidth and low-latency and makes optimal use of in-built features like RDMA. With the rapid evolution of InfiniBand technology and Ethernet lacking the RDMA and zero copy protocol, the Ethernet community has came out with a new enhancements that bridges the gap between InfiniBand and Ethernet. By adding the RDMA and zero copy protocol to the Ethernet a new networking technology is evolved, called RDMA over Converged Ethernet (RoCE). RoCE is a standard released by the IBTA standardization body to define RDMA protocol over Ethernet. With the emergence of lossless Ethernet, RoCE uses InfiniBand’s efficient transport to provide the platform for deploying RDMA technology in mainstream data centres over 10GigE, 40GigE and beyond. RoCE provide all of the InfiniBand benefits transport benefits and well established RDMA ecosystem combined with converged Ethernet. In this paper, we evaluate the heterogeneous Linux cluster, having multi nodes with fast interconnects i.e. gigabit Ethernet and Soft RoCE. This paper presents the heterogeneous Linux cluster configuration and evaluates its performance using Intel’s MPI Benchmarks. Our result shows that Soft RoCE is performing better than Ethernet in various performance metrics like bandwidth, latency and throughput.

Keywords: ethernet, InfiniBand, RoCE, RDMA, MPI, Soft RoCE

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11318 Mitigation of Interference in Satellite Communications Systems via a Cross-Layer Coding Technique

Authors: Mario A. Blanco, Nicholas Burkhardt

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An important problem in satellite communication systems which operate in the Ka and EHF frequency bands consists of the overall degradation in link performance of mobile terminals due to various types of degradations in the link/channel, such as fading, blockage of the link to the satellite (especially in urban environments), intentional as well as other types of interference, etc. In this paper, we focus primarily on the interference problem, and we develop a very efficient and cost-effective solution based on the use of fountain codes. We first introduce a satellite communications (SATCOM) terminal uplink interference channel model that is classically used against communication systems that use spread-spectrum waveforms. We then consider the use of fountain codes, with focus on Raptor codes, as our main mitigation technique to combat the degradation in link/receiver performance due to the interference signal. The performance of the receiver is obtained in terms of average probability of bit and message error rate as a function of bit energy-to-noise density ratio, Eb/N0, and other parameters of interest, via a combination of analysis and computer simulations, and we show that the use of fountain codes is extremely effective in overcoming the effects of intentional interference on the performance of the receiver and associated communication links. We then show this technique can be extended to mitigate other types of SATCOM channel degradations, such as those caused by channel fading, shadowing, and hard-blockage of the uplink signal.

Keywords: SATCOM, interference mitigation, fountain codes, turbo codes, cross-layer

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11317 Lowering Error Floors by Concatenation of Low-Density Parity-Check and Array Code

Authors: Cinna Soltanpur, Mohammad Ghamari, Behzad Momahed Heravi, Fatemeh Zare

Abstract:

Low-density parity-check (LDPC) codes have been shown to deliver capacity approaching performance; however, problematic graphical structures (e.g. trapping sets) in the Tanner graph of some LDPC codes can cause high error floors in bit-error-ratio (BER) performance under conventional sum-product algorithm (SPA). This paper presents a serial concatenation scheme to avoid the trapping sets and to lower the error floors of LDPC code. The outer code in the proposed concatenation is the LDPC, and the inner code is a high rate array code. This approach applies an interactive hybrid process between the BCJR decoding for the array code and the SPA for the LDPC code together with bit-pinning and bit-flipping techniques. Margulis code of size (2640, 1320) has been used for the simulation and it has been shown that the proposed concatenation and decoding scheme can considerably improve the error floor performance with minimal rate loss.

Keywords: concatenated coding, low–density parity–check codes, array code, error floors

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11316 BER Estimate of WCDMA Systems with MATLAB Simulation Model

Authors: Suyeb Ahmed Khan, Mahmood Mian

Abstract:

Simulation plays an important role during all phases of the design and engineering of communications systems, from early stages of conceptual design through the various stages of implementation, testing, and fielding of the system. In the present paper, a simulation model has been constructed for the WCDMA system in order to evaluate the performance. This model describes multiusers effects and calculation of BER (Bit Error Rate) in 3G mobile systems using Simulink MATLAB 7.1. Gaussian Approximation defines the multi-user effect on system performance. BER has been analyzed with comparison between transmitting data and receiving data.

Keywords: WCDMA, simulations, BER, MATLAB

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11315 Study of Adaptive Filtering Algorithms and the Equalization of Radio Mobile Channel

Authors: Said Elkassimi, Said Safi, B. Manaut

Abstract:

This paper presented a study of three algorithms, the equalization algorithm to equalize the transmission channel with ZF and MMSE criteria, application of channel Bran A, and adaptive filtering algorithms LMS and RLS to estimate the parameters of the equalizer filter, i.e. move to the channel estimation and therefore reflect the temporal variations of the channel, and reduce the error in the transmitted signal. So far the performance of the algorithm equalizer with ZF and MMSE criteria both in the case without noise, a comparison of performance of the LMS and RLS algorithm.

Keywords: adaptive filtering second equalizer, LMS, RLS Bran A, Proakis (B) MMSE, ZF

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11314 Effects of Work Load and Surface Acting on Emotional Exhaustion and Work Satisfaction of Social Worker Students: Chinese Indigenous Ren-Qing Shi-Ku Trait as Moderator

Authors: Chung-Kwei Wang, Kuo-Ying Lo

Abstract:

The study is aimed to examine main and moderation effect of Chinese traditional social wisdom ‘Ren-qing Shi-kuon' the adjustment of social worker students during their practicum. Ren-qing Shi-ku as a social wisdom has been emphasized by collective-oriented Chinese society for thousand years. Based on interview and literature review, we operationalized the concept as four factors, including ‘harmonious interaction’, ‘understanding and tolerance’, ‘empathetic communication’ and ‘rule abiding’. We administer the scale to 96 social worker senior students before their summer practicums begins and collect their response on emotion labor, emotional exhaustion, work load, work satisfaction. We also ask their supervisors rated their performance on empathy, interpersonal relationships, performance on practicum and their Ren-qing Shi-ku performance. Results indicated that self-ratings of students on Ren-qing Shi-ku scale are correlated with rating from their supervisors. Students who have higher Ren-qing Shi-ku have better adjustment and higher ratings from their supervisor. Ren-qing Shi-ku also moderate effects of surface acting labor and work load on emotional exhaustion and work satisfaction. However, Ren-qing Shi-ku seems more beneficial under low work load situations. The finding of this study suggested traditional social skill training might be very effective for social service providers in a collective-oriented culture.

Keywords: emotion labor, ren-qing shi-ku, emotional exhaustion, work satisfaction and performance

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11313 The Effect of Bilingualism on Prospective Memory

Authors: Aslı Yörük, Mevla Yahya, Banu Tavat

Abstract:

It is well established that bilinguals outperform monolinguals on executive function tasks. However, the effects of bilingualism on prospective memory (PM), which also requires executive functions, have not been investigated vastly. This study aimed to compare bi and monolingual participants' PM performance in focal and non-focal PM tasks. Considering that bilinguals have greater executive function abilities than monolinguals, we predict that bilinguals’ PM performance would be higher than monolinguals on the non-focal PM task, which requires controlled monitoring processes. To investigate these predictions, we administered the focal and non-focal PM task and measured the PM and ongoing task performance. Forty-eight Turkish-English bilinguals residing in North Macedonia and forty-eight Turkish monolinguals living in Turkey between the ages of 18-30 participated in the study. They were instructed to remember responding to rarely appearing PM cues while engaged in an ongoing task, i.e., spatial working memory task. The focality of the task was manipulated by giving different instructions for PM cues. In the focal PM task, participants were asked to remember to press an enter key whenever a particular target stimulus appeared in the working memory task; in the non-focal PM task, instead of responding to a specific target shape, participants were asked to remember to press the enter key whenever the background color of the working memory trials changes to a specific color (yellow). To analyze data, we performed a 2 × 2 mixed factorial ANOVA with the task (focal versus non-focal) as a within-subject variable and language group (bilinguals versus monolinguals) as a between-subject variable. The results showed no direct evidence for a bilingual advantage in PM. That is, the group’s performance did not differ in PM accuracy and ongoing task accuracy. However, bilinguals were overall faster in the ongoing task, yet this was not specific to PM cue’s focality. Moreover, the results showed a reversed effect of PM cue's focality on the ongoing task performance. That is, both bi and monolinguals showed enhanced performance in the non-focal PM cue task. These findings raise skepticism about the literature's prevalent findings and theoretical explanations. Future studies should investigate possible alternative explanations.

Keywords: bilingualism, executive functions, focality, prospective memory

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11312 Modelling the Effect of Alcohol Consumption on the Accelerating and Braking Behaviour of Drivers

Authors: Ankit Kumar Yadav, Nagendra R. Velaga

Abstract:

Driving under the influence of alcohol impairs the driving performance and increases the crash risks worldwide. The present study investigated the effect of different Blood Alcohol Concentrations (BAC) on the accelerating and braking behaviour of drivers with the help of driving simulator experiments. Eighty-two licensed Indian drivers drove on the rural road environment designed in the driving simulator at BAC levels of 0.00%, 0.03%, 0.05%, and 0.08% respectively. Driving performance was analysed with the help of vehicle control performance indicators such as mean acceleration and mean brake pedal force of the participants. Preliminary analysis reported an increase in mean acceleration and mean brake pedal force with increasing BAC levels. Generalized linear mixed models were developed to quantify the effect of different alcohol levels and explanatory variables such as driver’s age, gender and other driver characteristic variables on the driving performance indicators. Alcohol use was reported as a significant factor affecting the accelerating and braking performance of the drivers. The acceleration model results indicated that mean acceleration of the drivers increased by 0.013 m/s², 0.026 m/s² and 0.027 m/s² for the BAC levels of 0.03%, 0.05% and 0.08% respectively. Results of the brake pedal force model reported that mean brake pedal force of the drivers increased by 1.09 N, 1.32 N and 1.44 N for the BAC levels of 0.03%, 0.05% and 0.08% respectively. Age was a significant factor in both the models where one year increase in drivers’ age resulted in 0.2% reduction in mean acceleration and 19% reduction in mean brake pedal force of the drivers. It shows that driving experience could compensate for the negative effects of alcohol to some extent while driving. Female drivers were found to accelerate slower and brake harder as compared to the male drivers which confirmed that female drivers are more conscious about their safety while driving. It was observed that drivers who were regular exercisers had better control on their accelerator pedal as compared to the non-regular exercisers during drunken driving. The findings of the present study revealed that drivers tend to be more aggressive and impulsive under the influence of alcohol which deteriorates their driving performance. Drunk driving state can be differentiated from sober driving state by observing the accelerating and braking behaviour of the drivers. The conclusions may provide reference in making countermeasures against drinking and driving and contribute to traffic safety.

Keywords: alcohol, acceleration, braking behaviour, driving simulator

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11311 Developing a Driving Simulator with a Navigation System to Measure Driver Distraction, Workload, Driving Safety and Performance

Authors: Tamer E. Yared

Abstract:

The use of driving simulators has made laboratory testing easier. It has been proven to be valid for testing driving ability by many researchers. One benefit of using driving simulators is keeping the human subjects away from traffic hazards, which drivers usually face in a real driving environment while performing a driving experiment. In this study, a driving simulator was developed with a navigation system using a game development software (Unity 3D) and C-sharp codes to measure and evaluate driving performance, safety, and workload for different driving tasks. The driving simulator hardware included a gaming steering wheel and pedals as well as a monitor to view the driving tasks. Moreover, driver distraction was evaluated by utilizing an eye-tracking system working in conjunction with the driving simulator. Twenty subjects were recruited to evaluate driver distraction, workload, driving safety, and performance, as well as provide their feedback about the driving simulator. The subjects’ feedback was obtained by filling a survey after conducting several driving tasks. The main question of that survey was asking the subjects to compare driving on the driving simulator with real driving. Furthermore, other aspects of the driving simulator were evaluated by the subjects in the survey. The survey revealed that the recruited subjects gave an average score of 7.5 out of 10 to the driving simulator when compared to real driving, where the scores ranged between 6 and 8.5. This study is a preliminary effort that opens the door for more improvements to the driving simulator in terms of hardware and software development, which will contribute significantly to driving ability testing.

Keywords: driver distraction, driving performance, driving safety, driving simulator, driving workload, navigation system

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11310 Cuckoo Search (CS) Optimization Algorithm for Solving Constrained Optimization

Authors: Sait Ali Uymaz, Gülay Tezel

Abstract:

This paper presents the comparison results on the performance of the Cuckoo Search (CS) algorithm for constrained optimization problems. For constraint handling, CS algorithm uses penalty method. CS algorithm is tested on thirteen well-known test problems and the results obtained are compared to Particle Swarm Optimization (PSO) algorithm. Mean, best, median and worst values were employed for the analyses of performance.

Keywords: cuckoo search, particle swarm optimization, constrained optimization problems, penalty method

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11309 Information Technology and Professional Behavior: An Empirical Examination of Auditing and Accounting Tasks

Authors: Michael C. Nwaohia

Abstract:

Whereas anecdotal evidence supports the notion that increase in information technology (IT) know-how may enhance output of professionals in the accounting sector, this has not been systematically explored in the Nigerian context. Against this background, this paper examines the correlation between knowledgeability of IT and level of performance at everyday auditing and accounting tasks. It utilizes primary and secondary data from selected business organizations in Lagos, Nigeria. Accounting staff were administered structured questionnaires which, amongst other things, sought to examine knowledge and exposure to information technology prior to joining the firms and current level of performance based on self-reporting and supervisor comments. In addition, exposure to on-the-job IT training and current level of performance was examined. The statistical analysis of the data was done using the SPSS package. The results strongly suggest that prior exposure to IT skills enabled accounting professionals to better flexibly fit into the dynamic environment in which contemporary business takes place. Ultimately, the paper attempts to explicate some of the implications of these findings for individuals and business firms.

Keywords: accounting, firms, information technology, professional behavior

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11308 The Effect of Cooling Tower Fan on the Performance of the Chiller Plant

Authors: Ankitsinh Chauhan, Vimal Patel, A. D. Parekh, Ishant patil

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This study delves into the crucial influence of cooling tower fan operation on the performance of a chiller plant, with a specific focus on the Chiller Plant at SVNIT. Continuous operation of the chiller plant led to unexpected damage to the cooling tower's belt drive, rendering the cooling tower fan non-operational. Consequently, the efficiency of heat transfer in the condenser was significantly impaired. In response, we analyzed and calculated several vital parameters, including the Coefficient of Performance (COP), heat rejection in the condenser (Qc), work required for the compressor (Wc), and heat absorbed by the refrigerant in the evaporator (Qe). Our findings revealed that in the absence of the cooling tower fan, relying solely on natural convection, the COP of the chiller plant reached a minimum value of 5.49. However, after implementing a belt drive to facilitate forced convection for the cooling tower fan, the COP of the chiller plant experienced a noteworthy improvement, reaching approximately 6.27. Additionally, the utilization of forced convection resulted in an impressive reduction of 8.9% in compressor work, signifying enhanced energy efficiency. This study underscores the critical role of cooling tower fan operation in optimizing chiller plant performance, with practical implications for energy-efficient HVAC systems. It highlights the potential benefits of employing forced convection mechanisms, such as belt drives, to ensure efficient heat transfer in the condenser, ultimately contributing to improved energy utilization and reduced operational costs in cooling.

Keywords: cooling tower, chiller Plant, cooling tower fan, energy efficiency, VCRS.

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11307 Strategic Management Model for High Performance Sports Centers

Authors: Jose Ramon Sanabria Navarro, Yahilina Silveira Perez, Valentin Molina Moreno, Digna Dionisia Perez Bravo

Abstract:

The general objective of this research is to conceive a model of strategic direction for Latin American high-performance sports centers for the improvement of their results. The sample is 62 managers, 187 trainers, 2930 athletes and 62 expert researchers from centers in Cuba, Venezuela, Ecuador, Colombia and Argentina, for 3241. The measurement instrument includes 12 key variables in the process of management strategies which are consolidated with the factorial analysis and the ANOVA of a factor through the SPSS 24.0. The reliability of the scale obtained an alpha higher than 0.7 in each sample. In this sense, a model is obtained that taxes the deficiencies detected in the diagnosis, based on the needs of the members of these organizations, considering criteria and theories of the strategic direction in the improvement of the organizational results. The validation of the model for high performance sports centers of the countries analyzed aims to develop joint strategies to generate synergies in their operational mode, which leads to enhance the sports organization.

Keywords: sports organization, information management, decision making, control

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11306 Influence of Scrap Tyre Steel Fiber on Mechanical Properties of High Performance Concrete

Authors: Isyaka Abdulkadir, Egbe Ngu-Ntui Ogork

Abstract:

This research aims to investigate the use of Scrap Tyre Steel Fibers (STSF) for the production of fiber reinforced high performance concrete. The Scrap Tyre Steel Fibers (STSF) were obtained from dealers that extracted the fibers by burning the scrap tyres and were characterized. The effect of STSF was investigated on grade 50 concrete of 1:1.28:1.92 with water cement ratio of 0.39 at additions of STSF of 0, 0.5, 1.0, 1.5, 2.0 and 2.5% by volume of concrete. The fresh concrete was tested for slump while the hardened concrete was tested for compressive and splitting tensile strengths, respectively at curing ages of 3, 7, 28 and 56 days in accordance with standard procedure. The results indicate that slump decreased with increase in STSF, while compressive and splitting tensile strengths increased with increase in STSF up to 1.5% and reduction in strength with increase in STSF above 1.5%. 1.5% STSF was considered as the optimum dosage with a 28 days increase in compressive strength and splitting tensile strength of 12.3% and 43.8% respectively, of control.

Keywords: compressive strength, high performance concrete, scrap tyre steel fiber, splitting tensile strength

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11305 Propeller Performance Modeling through a Computational Fluid Dynamics Analysis Method

Authors: Maxime Alex Junior Kuitche, Ruxandra Mihaela Botez, Jean-Chirstophe Maunand

Abstract:

The evolution of aircraft is closely linked to the study and improvement of propulsion systems. Determining the propulsion performance is a real challenge in aircraft modeling and design. In addition to theoretical methodologies, experimental procedures are used to obtain a good estimation of the propulsion performances. For piston-propeller propulsion, the propeller needs several experimental tests which could be extremely demanding in terms of time and money. This paper presents a new procedure to estimate the performance of a propeller from a numerical approach using computational fluid dynamic analysis. The propeller was initially scanned, and then, its 3D model was represented using CATIA. A structured meshing and Shear Stress Transition k-ω turbulence model were applied to describe accurately the flow pattern around the propeller. Thus, the Partial Differential Equations were solved using ANSYS FLUENT software. The method was applied on the UAS-S45’s propeller designed and manufactured by Hydra Technologies in Mexico. An extensive investigation was performed for several flight conditions in terms of altitudes and airspeeds with the aim to determine thrust coefficients, power coefficients and efficiency of the propeller. The Computational Fluid Dynamics results were compared with experimental data acquired from wind tunnel tests performed at the LARCASE Price-Paidoussis wind tunnel. The results of this comparison have demonstrated that our approach was highly accurate.

Keywords: CFD analysis, propeller performance, unmanned aerial system propeller, UAS-S45

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11304 An Investigation of the Relationship Between Privacy Crisis, Public Discourse on Privacy, and Key Performance Indicators at Facebook (2004–2021)

Authors: Prajwal Eachempati, Laurent Muzellec, Ashish Kumar Jha

Abstract:

We use Facebook as a case study to investigate the complex relationship between the firm’s public discourse (and actions) surrounding data privacy and the performance of a business model based on monetizing user’s data. We do so by looking at the evolution of public discourse over time (2004–2021) and relate topics to revenue and stock market evolution Drawing from archival sources like Zuckerberg We use LDA topic modelling algorithm to reveal 19 topics regrouped in 6 major themes. We first show how, by using persuasive and convincing language that promises better protection of consumer data usage, but also emphasizes greater user control over their own data, the privacy issue is being reframed as one of greater user control and responsibility. Second, we aim to understand and put a value on the extent to which privacy disclosures have a potential impact on the financial performance of social media firms. There we found significant relationship between the topics pertaining to privacy and social media/technology, sentiment score and stock market prices. Revenue is found to be impacted by topics pertaining to politics and new product and service innovations while number of active users is not impacted by the topics unless moderated by external control variables like Return on Assets and Brand Equity.

Keywords: public discourses, data protection, social media, privacy, topic modeling, business models, financial performance

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11303 Performance Analysis of Bluetooth Low Energy Mesh Routing Algorithm in Case of Disaster Prediction

Authors: Asmir Gogic, Aljo Mujcic, Sandra Ibric, Nermin Suljanovic

Abstract:

Ubiquity of natural disasters during last few decades have risen serious questions towards the prediction of such events and human safety. Every disaster regardless its proportion has a precursor which is manifested as a disruption of some environmental parameter such as temperature, humidity, pressure, vibrations and etc. In order to anticipate and monitor those changes, in this paper we propose an overall system for disaster prediction and monitoring, based on wireless sensor network (WSN). Furthermore, we introduce a modified and simplified WSN routing protocol built on the top of the trickle routing algorithm. Routing algorithm was deployed using the bluetooth low energy protocol in order to achieve low power consumption. Performance of the WSN network was analyzed using a real life system implementation. Estimates of the WSN parameters such as battery life time, network size and packet delay are determined. Based on the performance of the WSN network, proposed system can be utilized for disaster monitoring and prediction due to its low power profile and mesh routing feature.

Keywords: bluetooth low energy, disaster prediction, mesh routing protocols, wireless sensor networks

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11302 The Effects of Displacer-Cylinder-Wall Conditions on the Performance of a Medium-Temperature-Differential γ-Type Stirling Engine

Authors: Wen-Lih Chen, Chao-Kuang Chen, Mao-Ju Fang, Hsiang-Cheng Hsu

Abstract:

In this study, we conducted CFD simulation to study the gas cycle of a medium-temperature-differential (MTD) γ-type Stirling engine. Mesh compression and expansion as well as overset mesh techniques are employed to simulate the moving parts of the engine. Shear-Stress Transport (SST) k-ω turbulence model has been adopted because the model is not prone to generate excessive turbulence upon impingement regions. Hence, wall heat transfer rates at the hot and cold ends will not be overestimated. The effects of several different displacer-cylinder-wall temperature setups, including smooth and finned walls, on engine performance are investigated. The results include temperature contours, pressure versus volume diagrams, and variations of heat transfer rates, indicated power, and efficiency. It is found that displacer-wall heat transfer is one of the most important factors on engine performance, and some wall-temperature setups produce better results than others.

Keywords: CFD, finned wall, MTD Stirling engine, heat transfer

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11301 Assessment of Multi-Domain Energy Systems Modelling Methods

Authors: M. Stewart, Ameer Al-Khaykan, J. M. Counsell

Abstract:

Emissions are a consequence of electricity generation. A major option for low carbon generation, local energy systems featuring Combined Heat and Power with solar PV (CHPV) has significant potential to increase energy performance, increase resilience, and offer greater control of local energy prices while complementing the UK’s emissions standards and targets. Recent advances in dynamic modelling and simulation of buildings and clusters of buildings using the IDEAS framework have successfully validated a novel multi-vector (simultaneous control of both heat and electricity) approach to integrating the wide range of primary and secondary plant typical of local energy systems designs including CHP, solar PV, gas boilers, absorption chillers and thermal energy storage, and associated electrical and hot water networks, all operating under a single unified control strategy. Results from this work indicate through simulation that integrated control of thermal storage can have a pivotal role in optimizing system performance well beyond the present expectations. Environmental impact analysis and reporting of all energy systems including CHPV LES presently employ a static annual average carbon emissions intensity for grid supplied electricity. This paper focuses on establishing and validating CHPV environmental performance against conventional emissions values and assessment benchmarks to analyze emissions performance without and with an active thermal store in a notional group of non-domestic buildings. Results of this analysis are presented and discussed in context of performance validation and quantifying the reduced environmental impact of CHPV systems with active energy storage in comparison with conventional LES designs.

Keywords: CHPV, thermal storage, control, dynamic simulation

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11300 Efficiency of an Algae-Zinc Complex Compared to Inorganic Zinc Sulfate on Broilers Performance

Authors: R. Boulmane, C. Alleno, D. Marzin

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Trace minerals play an essential role in vital processes and are essential to many biological and physiological functions of the animal. They are usually incorporated in the form of inorganic salts such as sulfates and oxides. Most of these inorganic salts are excreted undigested by the animal causing economic losses as well as environmental pollution. In this context, the use of alternative organic trace minerals with higher bioavailability is emerging. This study was set up to evaluate the effect of using an algae-zinc complex in replacement of zinc sulfate in the feed, on growth performance of broiler chickens. One-thousand-two-hundred 1-day-old chicks were randomly distributed to 30 pens, allocated to 1 of 3 groups receiving different diets: the standard diet containing 35ppm of inorganic zinc sulfate (C+), a test diet containing 35ppm of algae-based zinc (T+), and a test diet containing half dose (16ppm) of algae-based zinc (T-). Three different feeds were distributed from D0-D11, D11-D21 and D21-D35. Individual weighing of the animals (D21 and D35), feed consumption (D11, D21 and D35) and pododermatitis occurrence (D35) were monitored. Data were submitted to analysis of variance. Results show that in finishing period the ADWG of the T+ and T- groups are significantly higher than the control C+ (+6%, P = 0.03). On the other hand, the FCR for the total period is lower for both the T+ and T- groups than the control C+ (-1.2%, P = 0.04). Pododermatitis scoring also shows less lesions for the test groups with algae-based zinc compared to the control group receiving inorganic one. In the end, this study shows a positive effect of the algae zinc-complex on growth performance of broilers compared to inorganic zinc, both when using full dose (35 ppm) or half dose (16 ppm). The use of algae-zinc complex in the premix shows to be a good alternative to reduce zinc excretion while maintaining performance.

Keywords: algae-zinc complex, broiler performance, organic trace minerals, zinc sulfate

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11299 Mental Vulnerability and Coping Strategies as a Factor for Academic Success for Pupils with Special Education Needs

Authors: T. Dubayova

Abstract:

Slovak, as well as foreign authors, believe that the influence of non-cognitive factors on a student's academic success or failure is unquestionable. The aim of this paper is to establish a link between the mental vulnerability and coping strategies used by 4th grade elementary school students in dealing with stressful situations and their academic performance, which was used as a simple quantitative indicator of academic success. The research sample consists of 320 students representing the standard population and 60 students with special education needs (SEN), who were assessed by the Strengths and Difficulties Questionnaire (SDQ) by their teachers and the Children’s Coping Strategies Checklist (CCSC-R1) filled in by themselves. Students with SEN recorded an extraordinarily high frequency of mental vulnerability (34.5 %) than students representing the standard population (7 %). The poorest academic performance of students with SEN was associated with the avoidance behavior displayed during stressful situations. Students of the standard population did not demonstrate this association. Students with SEN are more likely to display mental health problems than students of the standard population. This may be caused by the accumulation of and frequent exposure to situations that they perceive as stressful.

Keywords: coping, mental vulnerability, pupil with special education needs, school performance, school success

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11298 Efficient Variable Modulation Scheme Based on Codebook in the MIMO-OFDM System

Authors: Yong-Jun Kim, Jae-Hyun Ro, Chang-Bin Ha, Hyoung-Kyu Song

Abstract:

Because current wireless communication requires high reliability in a limited bandwidth environment, this paper proposes the variable modulation scheme based on the codebook. The variable modulation scheme adjusts transmission power using the codebook in accordance with hannel state. Also, if the codebook is composed of many bits, the reliability is more improved by the proposed scheme. The simulation results show that the performance of proposed scheme has better reliability than the the performance of conventional scheme.

Keywords: MIMO-OFDM, variable modulation, codebook, channel state

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11297 Performance Analysis of SAC-OCDMA System using Different Detectors

Authors: Somaya A. Abd El Mottaleb, Ahmed Abd El Aziz, Heba A. Fayed, Moustafa H. Aly

Abstract:

In this paper, we present the performance of spectral amplitude coding optical code division multiple access using different detectors at different transmission distances using single photodiode detection technique. Modified double weight codes are used as signature codes. Simulation results show that the system using avalanche photo detector can move distance longer than that using positive intrinsic negative photo detector.

Keywords: avalanche photodiode, modified double weight, multiple access technique, single photodiode.

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11296 The Use of Performance Indicators for Evaluating Models of Drying Jackfruit (Artocarpus heterophyllus L.): Page, Midilli, and Lewis

Authors: D. S. C. Soares, D. G. Costa, J. T. S., A. K. S. Abud, T. P. Nunes, A. M. Oliveira Júnior

Abstract:

Mathematical models of drying are used for the purpose of understanding the drying process in order to determine important parameters for design and operation of the dryer. The jackfruit is a fruit with high consumption in the Northeast and perishability. It is necessary to apply techniques to improve their conservation for longer in order to diffuse it by regions with low consumption. This study aimed to analyse several mathematical models (Page, Lewis, and Midilli) to indicate one that best fits the conditions of convective drying process using performance indicators associated with each model: accuracy (Af) and noise factors (Bf), mean square error (RMSE) and standard error of prediction (% SEP). Jackfruit drying was carried out in convective type tray dryer at a temperature of 50°C for 9 hours. It is observed that the model Midili was more accurate with Af: 1.39, Bf: 1.33, RMSE: 0.01%, and SEP: 5.34. However, the use of the Model Midilli is not appropriate for purposes of control process due to need four tuning parameters. With the performance indicators used in this paper, the Page model showed similar results with only two parameters. It is concluded that the best correlation between the experimental and estimated data is given by the Page’s model.

Keywords: drying, models, jackfruit, biotechnology

Procedia PDF Downloads 379
11295 Density Measurement of Mixed Refrigerants R32+R1234yf and R125+R290 from 0°C to 100°C and at Pressures up to 10 MPa

Authors: Xiaoci Li, Yonghua Huang, Hui Lin

Abstract:

Optimization of the concentration of components in mixed refrigerants leads to potential improvement of either thermodynamic cycle performance or safety performance of heat pumps and refrigerators. R32+R1234yf and R125+R290 are two promising binary mixed refrigerants for the application of heat pumps working in the cold areas. The p-ρ-T data of these mixtures are one of the fundamental and necessary properties for design and evaluation of the performance of the heat pumps. Although the property data of mixtures can be predicted by the mixing models based on the pure substances incorporated in programs such as the NIST database Refprop, direct property measurement will still be helpful to reveal the true state behaviors and verify the models. Densities of the mixtures of R32+R1234yf an d R125+R290 are measured by an Anton Paar U shape oscillating tube digital densimeter DMA-4500 in the range of temperatures from 0°C to 100 °C and pressures up to 10 MPa. The accuracy of the measurement reaches 0.00005 g/cm³. The experimental data are compared with the predictions by Refprop in the corresponding range of pressure and temperature.

Keywords: mixed refrigerant, density measurement, densimeter, thermodynamic property

Procedia PDF Downloads 297
11294 Effects of Neem (Azadirachta indica A. Juss) Kernel Inclusion in Broiler Diet on Growth Performance, Organ Weight and Gut Morphometry

Authors: Olatundun Bukola Ezekiel, Adejumo Olusoji

Abstract:

A feeding trial was conducted with 100 two-weeks old broiler chicken to evaluate the influence of inclusion in broiler diets at 0, 2.5, 5, 7.5 and 10% neem kernel (used to replace equal quantity of maize) on their performance, organ weight and gut morphometry. The birds were randomly allotted to five dietary treatments, each treatment having four replicates consisting of five broilers in a completely randomized design. The diets were formulated to be iso-nitrogenous (23% CP). Weekly feed intake and changes in body weight were calculated and feed efficiency determined. At the end of the 28-day feeding trial, four broilers per treatment were selected and sacrificed for carcass evaluation. Results were subjected to statistical analysis using the analysis of variance procedures of Statistical Analysis Software The treatment means were presented with group standard errors of means and where significant, were compared using the Duncan multiple range test of the same software. The results showed that broilers fed 2.5% neem kernel inclusion diets had growth performance statistically comparable to those fed the control diet. Birds on 5, 7.5 and 10% neem kernel diets showed significant (P<0.05) increase in relative weight of liver. The absolute weight of spleen also increased significantly (P<0.05) in birds on 10 % neem kernel diet. More than 5 % neem kernel diets gave significant (P<0.05) increase in the relative weight of the kidney. The length of the small intestine significantly increased in birds fed 7.5 and 10% neem kernel diets. Significant differences (P<0.05) did not occur in the length of the large intestine, right and left caeca. It is recommended that neem kernel can be included up to 2.5% in broiler chicken diet without any deleterious effects on the performance and physiological status of the birds.

Keywords: broiler chicken, growth performance, gut morphometry, neem kernel, organ weight

Procedia PDF Downloads 763
11293 Productive Performance of Lactating Sows Feed with Cull Chickpea

Authors: J. M. Uriarte, H. R. Guemez, J. A. Romo, R. Barajas, J. M. Romo

Abstract:

This research was carried out with the objective of knowing the productive performance of sows in lactation when fed with diets containing cull chickpea instead of corn and soybean meal. Thirty-six (Landrace x Yorkshire) lactating sows were divided into three treatments with 12 sows per treatment. On day 107 of gestation, sows were moved into farrowing crates in an environmentally regulated (2.2 × 0.6 m) contained an area (2.2 × 0.5 m) for newborn pigs on each side, all diets were provided as a dry powder, and the sows received free access to water throughout the experimental period. After farrowing, daily feed allowance increased gradually, and sows had ad libitum access to feed by day four. They were fed diets containing 0 (CONT), cull chickpeas 15 % (CHP15), or cull chickpeas 30% (CHP30) for 28 days. The diets contained the same calculated levels of crude protein and metabolizable energy, and contained vitamins and minerals that exceeded the National Research Council (1998) recommendations; sows were fed three times daily. On day 28, piglets were weaned and performances of lactating sows and nursery piglets were recorded. All data in this experiment were analyzed in accordance with a completely randomized design. Results indicated that average daily feed intake (5.61, 5.59 and 5.46 kg for CONT, CHP15, and CHP30 respectively) of sows were not affected (P > 0.05) by different dietary. There was no difference (P > 0.05) in average body weight of piglets on the day of birth (1.35 vs. 1.30, and 1.32 kg) and day 28 (7.10, 6.80 and 6.92 kg) between treatments. The numbers of weaned piglets (10.65 on average) were not affected by treatments. It is concluded that the use of cull chickpea at 30% of the diet does not affect the productive performance of lactating sows.

Keywords: cull chickpea, lactating sow, performance, pigs

Procedia PDF Downloads 142
11292 Cross-Cultural Variations in Creative Perception Modulate Creative Performance

Authors: Anatoliy Kharkhurin

Abstract:

The study argues that variations in creative performance may be stipulated by cross-cultural differences in perception of the creativity construct. In Experiment 1, 50 Russian and 50 Emirati college students received structured imagination test that requires producing a drawing of an alien creature. In Experiment 2, 53 Russian and 53 Emirati college students (different from Experiment 1) on 5-point Likert-type scale evaluated the level of creativity of the drawings produced in the Experiment I. Repeated-measure ANOVA revealed an interaction between the country where the drawings were produced and the country where they were evaluated. Russians evaluated their country mates’ drawings as more creative than the Emiratis evaluated their country mates’ drawings. Regression analysis revealed that the creativity level of the drawings was positively predicted by the Russians’ evaluation and negatively predicted by the Emiratis’ evaluation. Finally, the evaluation of the drawings by the Russians predicted divergent thinking performance.

Keywords: creativity, culture, cross-cultural, perception, production

Procedia PDF Downloads 331
11291 Analysis of Accurate Direct-Estimation of the Maximum Power Point and Thermal Characteristics of High Concentration Photovoltaic Modules

Authors: Yan-Wen Wang, Chu-Yang Chou, Jen-Cheng Wang, Min-Sheng Liao, Hsuan-Hsiang Hsu, Cheng-Ying Chou, Chen-Kang Huang, Kun-Chang Kuo, Joe-Air Jiang

Abstract:

Performance-related parameters of high concentration photovoltaic (HCPV) modules (e.g. current and voltage) are required when estimating the maximum power point using numerical and approximation methods. The maximum power point on the characteristic curve for a photovoltaic module varies when temperature or solar radiation is different. It is also difficult to estimate the output performance and maximum power point (MPP) due to the special characteristics of HCPV modules. Based on the p-n junction semiconductor theory, a brand new and simple method is presented in this study to directly evaluate the MPP of HCPV modules. The MPP of HCPV modules can be determined from an irradiated I-V characteristic curve, because there is a non-linear relationship between the temperature of a solar cell and solar radiation. Numerical simulations and field tests are conducted to examine the characteristics of HCPV modules during maximum output power tracking. The performance of the presented method is evaluated by examining the dependence of temperature and irradiation intensity on the MPP characteristics of HCPV modules. These results show that the presented method allows HCPV modules to achieve their maximum power and perform power tracking under various operation conditions. A 0.1% error is found between the estimated and the real maximum power point.

Keywords: energy performance, high concentrated photovoltaic, maximum power point, p-n junction semiconductor

Procedia PDF Downloads 584