Search results for: run length coding
Commenced in January 2007
Frequency: Monthly
Edition: International
Paper Count: 3130

Search results for: run length coding

3040 Perceptual Image Coding by Exploiting Internal Generative Mechanism

Authors: Kuo-Cheng Liu

Abstract:

In the perceptual image coding, the objective is to shape the coding distortion such that the amplitude of distortion does not exceed the error visibility threshold, or to remove perceptually redundant signals from the image. While most researches focus on color image coding, the perceptual-based quantizer developed for luminance signals are always directly applied to chrominance signals such that the color image compression methods are inefficient. In this paper, the internal generative mechanism is integrated into the design of a color image compression method. The internal generative mechanism working model based on the structure-based spatial masking is used to assess the subjective distortion visibility thresholds that are visually consistent to human eyes better. The estimation method of structure-based distortion visibility thresholds for color components is further presented in a locally adaptive way to design quantization process in the wavelet color image compression scheme. Since the lowest subband coefficient matrix of images in the wavelet domain preserves the local property of images in the spatial domain, the error visibility threshold inherent in each coefficient of the lowest subband for each color component is estimated by using the proposed spatial error visibility threshold assessment. The threshold inherent in each coefficient of other subbands for each color component is then estimated in a local adaptive fashion based on the distortion energy allocation. By considering that the error visibility thresholds are estimated using predicting and reconstructed signals of the color image, the coding scheme incorporated with locally adaptive perceptual color quantizer does not require side information. Experimental results show that the entropies of three color components obtained by using proposed IGM-based color image compression scheme are lower than that obtained by using the existing color image compression method at perceptually lossless visual quality.

Keywords: internal generative mechanism, structure-based spatial masking, visibility threshold, wavelet domain

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3039 Germination and Seed Vigor Response of Five Wheat Cultivars to Stress of Premature Aging Effects

Authors: Mehdi Soltani Howyzeh, Neda Kardoni, Mani Mojadam

Abstract:

To evaluate the vigor of wheat seeds and stress of premature aging effects on germination percentage, root length and shoot length of five wheat cultivars that include Vynak, Karkheh, Chamran, Star and Kavir which underwent a period of zero, two, three, four days in terms of premature aging with 41 °C temperature and 100% relative humidity. Seed germination percentage, root length and shoot length in these conditions were measured. This experiment was conducted as a factorial completely randomized design with four replications in laboratory conditions. The results showed that each of aging treatments used in this experiment can be used to detect differences in vigor of wheat varieties. Wheat cultivars illustrated significant differences in germination percentage, root length and shoot length in terms of premature aging. The wheat cultivars; Astar and Vynak had maximum germination percentage and Karkheh, respectively Kavir and Chamran had lowest percentage of seed germination. Reactions of root and shoot length of wheat cultivars was also different. The results showed that the seeds with a stronger vigor affected less in premature aging condition and the difference between the percentage of seed germination under normal conditions and stress was significant and the seeds with the weaker vigor were more sensitive to the premature aging stress and the premature aging had more severe negative impact on seed vigor.

Keywords: wheat cultivars, seed vigor, premature aging effects, germination

Procedia PDF Downloads 303
3038 Stature Prediction from Anthropometry of Extremities among Jordanians

Authors: Amal A. Mashali, Omar Eltaweel, Elerian Ekladious

Abstract:

Stature of an individual has an important role in identification, which is often required in medico-legal practice. The estimation of stature is an important step in the identification of dismembered remains or when only a part of a skeleton is only available as in major disasters or with mutilation. There is no published data on anthropological data among Jordanian population. The present study was designed in order to find out relationship of stature to some anthropometric measures among a sample of Jordanian population and to determine the most accurate and reliable one in predicting the stature of an individual. A cross sectional study was conducted on 336 adult healthy volunteers , free of bone diseases, nutritional diseases and abnormalities in the extremities after taking their consent. Students of Faculty of Medicine, Mutah University helped in collecting the data. The anthropometric measurements (anatomically defined) were stature, humerus length, hand length and breadth, foot length and breadth, foot index and knee height on both right and left sides of the body. The measurements were typical on both sides of the bodies of the studied samples. All the anthropologic data showed significant relation with age except the knee height. There was a significant difference between male and female measurements except for the foot index where F= 0.269. There was a significant positive correlation between the different measures and the stature of the individuals. Three equations were developed for estimation of stature. The most sensitive measure for prediction of a stature was found to be the humerus length.

Keywords: foot index, foot length, hand length, humerus length, stature

Procedia PDF Downloads 261
3037 Partial M-Sequence Code Families Applied in Spectral Amplitude Coding Fiber-Optic Code-Division Multiple-Access Networks

Authors: Shin-Pin Tseng

Abstract:

Nowadays, numerous spectral amplitude coding (SAC) fiber-optic code-division-multiple-access (FO-CDMA) techniques were appealing due to their capable of providing moderate security and relieving the effects of multiuser interference (MUI). Nonetheless, the performance of the previous network is degraded due to fixed in-phase cross-correlation (IPCC) value. Based on the above problems, a new SAC FO-CDMA network using partial M-sequence (PMS) code is presented in this study. Because the proposed PMS code is originated from M-sequence code, the system using the PMS code could effectively suppress the effects of MUI. In addition, two-code keying (TCK) scheme can applied in the proposed SAC FO-CDMA network and enhance the whole network performance. According to the consideration of system flexibility, simple optical encoders/decoders (codecs) using fiber Bragg gratings (FBGs) were also developed. First, we constructed a diagram of the SAC FO-CDMA network, including (N/2-1) optical transmitters, (N/2-1) optical receivers, and one N×N star coupler for broadcasting transmitted optical signals to arrive at the input port of each optical receiver. Note that the parameter N for the PMS code was the code length. In addition, the proposed SAC network was using superluminescent diodes (SLDs) as light sources, which then can save a lot of system cost compared with the other FO-CDMA methods. For the design of each optical transmitter, it is composed of an SLD, one optical switch, and two optical encoders according to assigned PMS codewords. On the other hand, each optical receivers includes a 1 × 2 splitter, two optical decoders, and one balanced photodiode for mitigating the effect of MUI. In order to simplify the next analysis, the some assumptions were used. First, the unipolarized SLD has flat power spectral density (PSD). Second, the received optical power at the input port of each optical receiver is the same. Third, all photodiodes in the proposed network have the same electrical properties. Fourth, transmitting '1' and '0' has an equal probability. Subsequently, by taking the factors of phase‐induced intensity noise (PIIN) and thermal noise, the corresponding performance was displayed and compared with the performance of the previous SAC FO-CDMA networks. From the numerical result, it shows that the proposed network improved about 25% performance than that using other codes at BER=10-9. This is because the effect of PIIN was effectively mitigated and the received power was enhanced by two times. As a result, the SAC FO-CDMA network using PMS codes has an opportunity to apply in applications of the next-generation optical network.

Keywords: spectral amplitude coding, SAC, fiber-optic code-division multiple-access, FO-CDMA, partial M-sequence, PMS code, fiber Bragg grating, FBG

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3036 Improved Performance Scheme for Joint Transmission in Downlink Coordinated Multi-Point Transmission

Authors: Young-Su Ryu, Su-Hyun Jung, Myoung-Jin Kim, Hyoung-Kyu Song

Abstract:

In this paper, improved performance scheme for joint transmission is proposed in downlink (DL) coordinated multi-point(CoMP) in case of constraint transmission power. This scheme is that serving transmission point (TP) request a joint transmission to inter-TP and selects one pre-coding technique according to channel state information(CSI) from user equipment(UE). The simulation results show that the bit error rate(BER) and throughput performances of the proposed scheme provide high spectral efficiency and reliable data at the cell edge.

Keywords: CoMP, joint transmission, minimum mean square error, zero-forcing, zero-forcing dirty paper coding

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3035 Adhesion Performance According to Lateral Reinforcement Method of Textile

Authors: Jungbhin You, Taekyun Kim, Jongho Park, Sungnam Hong, Sun-Kyu Park

Abstract:

Reinforced concrete has been mainly used in construction field because of excellent durability. However, it may lead to reduction of durability and safety due to corrosion of reinforcement steels according to damage of concrete surface. Recently, research of textile is ongoing to complement weakness of reinforced concrete. In previous research, only experiment of longitudinal length were performed. Therefore, in order to investigate the adhesion performance according to the lattice shape and the embedded length, the pull-out test was performed on the roving with parameter of the number of lateral reinforcement, the lateral reinforcement length and the lateral reinforcement spacing. As a result, the number of lateral reinforcement and the lateral reinforcement length did not significantly affect the load variation depending on the adhesion performance, and only the load analysis results according to the reinforcement spacing are affected.

Keywords: adhesion performance, lateral reinforcement, pull-out test, textile

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3034 Accuracy of Small Field of View CBCT in Determining Endodontic Working Length

Authors: N. L. S. Ahmad, Y. L. Thong, P. Nambiar

Abstract:

An in vitro study was carried out to evaluate the feasibility of small field of view (FOV) cone beam computed tomography (CBCT) in determining endodontic working length. The objectives were to determine the accuracy of CBCT in measuring the estimated preoperative working lengths (EPWL), endodontic working lengths (EWL) and file lengths. Access cavities were prepared in 27 molars. For each root canal, the baseline electronic working length was determined using an EAL (Raypex 5). The teeth were then divided into overextended, non-modified and underextended groups and the lengths were adjusted accordingly. Imaging and measurements were made using the respective software of the RVG (Kodak RVG 6100) and CBCT units (Kodak 9000 3D). Root apices were then shaved and the apical constrictions viewed under magnification to measure the control working lengths. The paired t-test showed a statistically significant difference between CBCT EPWL and control length but the difference was too small to be clinically significant. From the Bland Altman analysis, the CBCT method had the widest range of 95% limits of agreement, reflecting its greater potential of error. In measuring file lengths, RVG had a bigger window of 95% limits of agreement compared to CBCT. Conclusions: (1) The clinically insignificant underestimation of the preoperative working length using small FOV CBCT showed that it is acceptable for use in the estimation of preoperative working length. (2) Small FOV CBCT may be used in working length determination but it is not as accurate as the currently practiced method of using the EAL. (3) It is also more accurate than RVG in measuring file lengths.

Keywords: accuracy, CBCT, endodontics, measurement

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3033 Establishing Student Support Strategies for Virtual Learning in Learning Management System Based on Grounded Theory

Authors: Farhad Shafiepour Motlagh, Narges Salehi

Abstract:

Purpose: The purpose of this study was to support student strategies for virtual learning in the learning management system. Methodology: The research method was based on grounded theory. The statistical population included all the articles of the ten years 2022-2010, and the sampling method was purposeful to the extent of theoretical saturation (n=31 ). Data collection was done by referring to the authoritative scientific databases of Emerald, Springer, Elsevier, Google Scholar, Sage Publication, and Science Direct. For data analysis, open coding, axial coding, and selective coding were used. Results: The results showed that causal conditions include cognitive empowerment (comprehension, analysis, composition), emotional empowerment (learning motivation, involvement in the learning system, enthusiasm for learning), psychomotor empowerment (learning to master, internalizing learning skills, creativity in learning). Conclusion: Supporting students requires their empowerment in three dimensions: cognitive, emotional empowerment, and psychomotor empowerment. In such a way that by introducing them to enter the learning management system, the capacities of the system, the toolkit of learning in the system, improve the motivation to learn in them, and in such a case, by learning more in the learning management system, they will reach mastery learning.

Keywords: student support, virtual education, learning management system, electronic

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3032 Pullout Strength of Textile Reinforcement in Concrete by Embedded Length and Concrete Strength

Authors: Jongho Park, Taekyun Kim, Jungbhin You, Sungnam Hong, Sun-Kyu Park

Abstract:

The deterioration of the reinforced concrete is continuously accelerated due to aging of the reinforced concrete, enlargement of the structure, increase if the self-weight due to the manhattanization and cracking due to external force. Also, due to the abnormal climate phenomenon, cracking of reinforced concrete structures is accelerated. Therefore, research on the Textile Reinforced Concrete (TRC) which replaced reinforcement with textile is under study. However, in previous studies, adhesion performance to single yarn was examined without parameters, which does not reflect the effect of fiber twisting and concrete strength. In the present paper, the effect of concrete strength and embedded length on 2400tex (gram per 1000 meters) and 640tex textile were investigated. The result confirm that the increasing compressive strength of the concrete did not affect the pullout strength. However, as the embedded length increased, the pullout strength tended to increase gradually, especially at 2400tex with more twists.

Keywords: textile, TRC, pullout, strength, embedded length, concrete

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3031 Mixtures of Length-Biased Weibull Distributions for Loss Severity Modelling

Authors: Taehan Bae

Abstract:

In this paper, a class of length-biased Weibull mixtures is presented to model loss severity data. The proposed model generalizes the Erlang mixtures with the common scale parameter, and it shares many important modelling features, such as flexibility to fit various data distribution shapes and weak-denseness in the class of positive continuous distributions, with the Erlang mixtures. We show that the asymptotic tail estimate of the length-biased Weibull mixture is Weibull-type, which makes the model effective to fit loss severity data with heavy-tailed observations. A method of statistical estimation is discussed with applications on real catastrophic loss data sets.

Keywords: Erlang mixture, length-biased distribution, transformed gamma distribution, asymptotic tail estimate, EM algorithm, expectation-maximization algorithm

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3030 Actual Fracture Length Determination Using a Technique for Shale Fracturing Data Analysis in Real Time

Authors: M. Wigwe, M. Y Soloman, E. Pirayesh, R. Eghorieta, N. Stegent

Abstract:

The moving reference point (MRP) technique has been used in the analyses of the first three stages of two fracturing jobs. The results obtained verify the proposition that a hydraulic fracture in shale grows in spurts rather than in a continuous pattern as originally interpreted by Nolte-Smith technique. Rather than a continuous Mode I fracture that is followed by Mode II, III or IV fractures, these fracture modes could alternate throughout the pumping period. It is also shown that the Nolte-Smith time parameter plot can be very helpful in identifying the presence of natural fractures that have been intersected by the hydraulic fracture. In addition, with the aid of a fracture length-time plot generated from any fracture simulation that matches the data, the distance from the wellbore to the natural fractures, which also translates to the actual fracture length for the stage, can be determined. An algorithm for this technique is developed. This procedure was used for the first 9 minutes of the simulated frac job data. It was observed that after 7mins, the actual fracture length is about 150ft, instead of 250ft predicted by the simulator output. This difference gets larger as the analysis proceeds.

Keywords: shale, fracturing, reservoir, simulation, frac-length, moving-reference-point

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3029 Edge Detection and Morphological Image for Estimating Gestational Age Based on Fetus Length Automatically

Authors: Retno Supriyanti, Ahmad Chuzaeri, Yogi Ramadhani, A. Haris Budi Widodo

Abstract:

The use of ultrasonography in the medical world has been very popular including the diagnosis of pregnancy. In determining pregnancy, ultrasonography has many roles, such as to check the position of the fetus, abnormal pregnancy, fetal age and others. Unfortunately, all these things still need to analyze the role of the obstetrician in the sense of image raised by ultrasonography. One of the most striking is the determination of gestational age. Usually, it is done by measuring the length of the fetus manually by obstetricians. In this study, we developed a computer-aided diagnosis for the determination of gestational age by measuring the length of the fetus automatically using edge detection method and image morphology. Results showed that the system is sufficiently accurate in determining the gestational age based image processing.

Keywords: computer aided diagnosis, gestational age, and diameter of uterus, length of fetus, edge detection method, morphology image

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3028 Efficient DCT Architectures

Authors: Mr. P. Suryaprasad, R. Lalitha

Abstract:

This paper presents an efficient area and delay architectures for the implementation of one dimensional and two dimensional discrete cosine transform (DCT). These are supported to different lengths (4, 8, 16, and 32). DCT blocks are used in the different video coding standards for the image compression. The 2D- DCT calculation is made using the 2D-DCT separability property, such that the whole architecture is divided into two 1D-DCT calculations by using a transpose buffer. Based on the existing 1D-DCT architecture two different types of 2D-DCT architectures, folded and parallel types are implemented. Both of these two structures use the same transpose buffer. Proposed transpose buffer occupies less area and high speed than existing transpose buffer. Hence the area, low power and delay of both the 2D-DCT architectures are reduced.

Keywords: transposition buffer, video compression, discrete cosine transform, high efficiency video coding, two dimensional picture

Procedia PDF Downloads 487
3027 The Twelfth Rib as a Landmark for Surgery

Authors: Jake Tempo, Georgina Williams, Iain Robertson, Claire Pascoe, Darren Rama, Richard Cetti

Abstract:

Introduction: The twelfth rib is commonly used as a landmark for surgery; however, its variability in length has not been formally studied. The highly variable rib length provides a challenge for urologists seeking a consistent landmark for percutaneous nephrolithotomy and retroperitoneoscopic surgery. Methods and materials: We analysed CT scans of 100 adults who had imaging between 23rd March and twelfth April 2020 at an Australian Hospital. We measured the distance from the mid-sagittal line to the twelfth rib tip in the axial plane as a surrogate for true rib length. We also measured the distance from the twelfth rib tip to the kidney, spleen, and liver. Results: Length from the mid-sagittal line to the right twelfth rib tip varied from 46 (percentile 95%CI 40 to 57) to 136mm (percentile 95%CI 133 to 138). On the left, the distances varied from 55 (percentile 95%CI 50 to 64) to 134mm (percentile 95%CI 131 to 135). Twenty-three percent of people had an organ lying between the tip of the twelfth rib and the kidney on the right, and 11% of people had the same finding on the left. Conclusion: The twelfth rib is highly variable in its length. Similar variability was recorded in the distance from the tip to intra-abdominal organs. Due to the frequency of organs lying between the tip of the rib and the kidney, it should not be used as a landmark for accessing the kidney without prior knowledge of an individual patient’s anatomy, as seen on imaging.

Keywords: PCNL, rib, anatomy, nephrolithotomy

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3026 Performance Analysis of IDMA Scheme Using Quasi-Cyclic Low Density Parity Check Codes

Authors: Anurag Saxena, Alkesh Agrawal, Dinesh Kumar

Abstract:

The next generation mobile communication systems i.e. fourth generation (4G) was developed to accommodate the quality of service and required data rate. This project focuses on multiple access technique proposed in 4G communication systems. It is attempted to demonstrate the IDMA (Interleave Division Multiple Access) technology. The basic principle of IDMA is that interleaver is different for each user whereas CDMA employs different signatures. IDMA inherits many advantages of CDMA such as robust against fading, easy cell planning; dynamic channel sharing and IDMA increase the spectral efficiency and reduce the receiver complexity. In this, performance of IDMA is analyzed using QC-LDPC coding scheme further it is compared with LDPC coding and at last BER is calculated and plotted in MATLAB.

Keywords: 4G, QC-LDPC, CDMA, IDMA

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3025 Growth Performance, Body Linear Measurements and Body Condition Score of Savanna Brown Goats Fed Enzyme Treated Sawdust Diets as Replacement for Maize Offal and Managed Semi-intensively

Authors: Alabi Olushola John, Ogbiko Anthonia, Tsado Daniel Nma, Mbajiorgu Ejike Felix, Adama Theophilus Zubairu

Abstract:

A total of thirty (30) goats weighting between 5.8 and 7.3 kg were used to determine the growth performance, body linear measurements and body condition score of Semi intensively manged Savanna Brown goats fed enzyme treated sawdust diets (ETSD). They divided into five dietary treatments (T) groups with three replications using a completely randomized design. Treatment one (1) comprises of animals fed diet on 0 % enzyme treated sawdust while Treatment 2 (T2), Treatment 3 (T3), Treatment 4 (T4) and Treatment 5 (T5) comprises of animals fed diets containing 10, 20, 30 and 40 % enzyme treated sawdust diets, respectively. The study lasted 16 weeks. Data on growth performance parameters, body linear measurement (height at wither, body length, chest girth, hind leg length, foreleg length, facial length) and body condition score were collected and analyzed using one way analysis of variance. No significant difference (p>0.05) was observed in the all growth performance parameters and linear body measurements. However, significant difference was observed in body length and daily body length gains with highest value observed in animals fed the control diets (7.38 and 0.08 cm respectively) and animals on 30 % ETSD (7.25 and 0.07 cm respectively) and lowest values (4.75 and 0.05 cm respectively) were observed in animals fed 10 % ETSD among the treatment groups. It was, therefore, concluded that enzyme treated sawdust can be used in the diets of Savanna Brown goats up to 40 % replacement for maize offal since this treatment improved the body length and daily body length gains.

Keywords: performance, sawdust, enzyme treated, semi-intensively, replacement

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3024 Evolution under Length Constraints for Convolutional Neural Networks Architecture Design

Authors: Ousmane Youme, Jean Marie Dembele, Eugene Ezin, Christophe Cambier

Abstract:

In recent years, the convolutional neural networks (CNN) architectures designed by evolution algorithms have proven to be competitive with handcrafted architectures designed by experts. However, these algorithms need a lot of computational power, which is beyond the capabilities of most researchers and engineers. To overcome this problem, we propose an evolution architecture under length constraints. It consists of two algorithms: a search length strategy to find an optimal space and a search architecture strategy based on a genetic algorithm to find the best individual in the optimal space. Our algorithms drastically reduce resource costs and also keep good performance. On the Cifar-10 dataset, our framework presents outstanding performance with an error rate of 5.12% and only 4.6 GPU a day to converge to the optimal individual -22 GPU a day less than the lowest cost automatic evolutionary algorithm in the peer competition.

Keywords: CNN architecture, genetic algorithm, evolution algorithm, length constraints

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3023 Audit on the Use of T-MACS Decision Aid for Patients Presenting to ED with Chest Pain

Authors: Saurav Dhawan, Sanchit Bansal

Abstract:

Background T-MACS is a computer-based decision aid that ‘rules in’ and ‘rules out’ ACS using a combination of the presence or absence of six clinical features with only one biomarker measured on arrival: hs-cTnT. T-MACS had 99.3% negative predictive value and 98.7% sensitivity for ACS, ‘ruling out’ ACS in 40% of patients while ‘ruling in’ 5% at the highest risk. We aim at benchmarking the use of T-MACS which could help to conserve healthcare resources, facilitate early discharges, and ensure safe practice. Methodology Randomized retrospective data collection (n=300) was done from ED electronic records across 3 hospital sites within MFT over a period of 2 months. Data was analysed and compared by percentage for the usage of T-MACS, number of admissions/discharges, and in days for length of stay in hospital. Results MRI A&E had the maximum compliance with the use of T-MACS in the trust at 66%, with minimum admissions (44%) and an average length of stay of 1.825 days. NMG A&E had an extremely low compliance rate (8 %), with 75% admission and 3.387 days as the average length of stay. WYT A&E had no TMACS recorded, with a maximum of 79% admissions and the longest average length of stay at 5.07 days. Conclusion All three hospital sites had a RAG rating of ‘RED’ as per the compliance levels. The assurance level was calculated as ‘Very Limited’ across all sites. There was a positive correlation observed between compliance with TMACS and direct discharges from ED, thereby reducing the average length of stay for patients in the hospital.

Keywords: ACS, discharges, ED, T-MACS

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3022 Coding Considerations for Standalone Molecular Dynamics Simulations of Atomistic Structures

Authors: R. O. Ocaya, J. J. Terblans

Abstract:

The laws of Newtonian mechanics allow ab-initio molecular dynamics to model and simulate particle trajectories in material science by defining a differentiable potential function. This paper discusses some considerations for the coding of ab-initio programs for simulation on a standalone computer and illustrates the approach by C language codes in the context of embedded metallic atoms in the face-centred cubic structure. The algorithms use velocity-time integration to determine particle parameter evolution for up to several thousands of particles in a thermodynamical ensemble. Such functions are reusable and can be placed in a redistributable header library file. While there are both commercial and free packages available, their heuristic nature prevents dissection. In addition, developing own codes has the obvious advantage of teaching techniques applicable to new problems.

Keywords: C language, molecular dynamics, simulation, embedded atom method

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3021 The Effect of Bottom Shape and Baffle Length on the Flow Field in Stirred Tanks in Turbulent and Transitional Flow

Authors: Jie Dong, Binjie Hu, Andrzej W Pacek, Xiaogang Yang, Nicholas J. Miles

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The effect of the shape of the vessel bottom and the length of baffles on the velocity distributions in a turbulent and in a transitional flow has been simulated. The turbulent flow was simulated using standard k-ε model and simulation was verified using LES whereas transitional flow was simulated using only LES. It has been found that both the shape of tank bottom and the baffles’ length has significant effect on the flow pattern and velocity distribution below the impeller. In the dished bottom tank with baffles reaching the edge of the dish, the large rotating volume of liquid was formed below the impeller. Liquid in this rotating region was not fully mixing. A dead zone was formed here. The size and the intensity of circulation within this zone calculated by k-ε model and LES were practically identical what reinforces the accuracy of the numerical simulations. Both types of simulations also show that employing full-length baffles can reduce the size of dead zone formed below the impeller. The LES was also used to simulate the velocity distribution below the impeller in transitional flow and it has been found that secondary circulation loops were formed near the tank bottom in all investigated geometries. However, in this case the length of baffles has smaller effect on the volume of rotating liquid than in the turbulent flow.

Keywords: baffles length, dished bottom, dead zone, flow field

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3020 Landmark Based Catch Trends Assessment of Gray Eel Catfish (Plotosus canius) at Mangrove Estuary in Bangladesh

Authors: Ahmad Rabby

Abstract:

The present study emphasizing the catch trends assessment of Gray eel catfish (Plotosus canius) that was scrutinized on the basis of monthly length frequency data collected from mangrove estuary, Bangladesh during January 2017 to December 2018. A total amount of 1298 specimens were collected to estimate the total length (TL) and weight (W) of P. canius ranged from 13.3 cm to 87.4 cm and 28 g to 5200 g, respectively. The length-weight relationship was W=0.006 L2.95 with R2=0.972 for both sexes. The von Bertalanffy growth function parameters were L∞=93.25 cm and K=0.28 yr-1, hypothetical age at zero length of t0=0.059 years and goodness of the fit of Rn=0.494. The growth performances indices for L∞ and W∞ were computed as Φ'=3.386 and Φ=1.84, respectively. The size at first sexual maturity was estimated in TL as 48.8 cm for pool sexes. The natural mortality was 0.51 yr-1 at average annual water surface temperature as 22 0C. The total instantaneous mortality was 1.24 yr-1 at CI95% of 0.105–1.42 (r2=0.986). While fishing mortality was 0.73 yr-1 and the current exploitation ratio as 0.59. The recruitment was continued throughout the year with one major peak during May-June was 17.20-17.96%. The Beverton-Holt yield per recruit model was analyzed by FiSAT-II, when tc was at 1.43 yr, the Fmax was estimated as 0.6 yr-1 and F0.1 was 0.33 yr-1. Current age at the first capture was approximately 0.6 year, however Fcurrent = 0.73 yr-1 which is beyond the F0.1 indicated that the current stock of P. canius of Bangladesh was overexploited.

Keywords: Plotosus canius, mangrove estuary, asymptotic length, FiSAT-II

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3019 Data Quality Enhancement with String Length Distribution

Authors: Qi Xiu, Hiromu Hota, Yohsuke Ishii, Takuya Oda

Abstract:

Recently, collectable manufacturing data are rapidly increasing. On the other hand, mega recall is getting serious as a social problem. Under such circumstances, there are increasing needs for preventing mega recalls by defect analysis such as root cause analysis and abnormal detection utilizing manufacturing data. However, the time to classify strings in manufacturing data by traditional method is too long to meet requirement of quick defect analysis. Therefore, we present String Length Distribution Classification method (SLDC) to correctly classify strings in a short time. This method learns character features, especially string length distribution from Product ID, Machine ID in BOM and asset list. By applying the proposal to strings in actual manufacturing data, we verified that the classification time of strings can be reduced by 80%. As a result, it can be estimated that the requirement of quick defect analysis can be fulfilled.

Keywords: string classification, data quality, feature selection, probability distribution, string length

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3018 Evaluation of Spatial Correlation Length and Karhunen-Loeve Expansion Terms for Predicting Reliability Level of Long-Term Settlement in Soft Soils

Authors: Mehrnaz Alibeikloo, Hadi Khabbaz, Behzad Fatahi

Abstract:

The spectral random field method is one of the widely used methods to obtain more reliable and accurate results in geotechnical problems involving material variability. Karhunen-Loeve (K-L) expansion method was applied to perform random field discretization of cross-correlated creep parameters. Karhunen-Loeve expansion method is based on eigenfunctions and eigenvalues of covariance function adopting Kernel integral solution. In this paper, the accuracy of Karhunen-Loeve expansion was investigated to predict long-term settlement of soft soils adopting elastic visco-plastic creep model. For this purpose, a parametric study was carried to evaluate the effect of K-L expansion terms and spatial correlation length on the reliability of results. The results indicate that small values of spatial correlation length require more K-L expansion terms. Moreover, by increasing spatial correlation length, the coefficient of variation (COV) of creep settlement increases, confirming more conservative and safer prediction.

Keywords: Karhunen-Loeve expansion, long-term settlement, reliability analysis, spatial correlation length

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3017 In vitro Culture of Stem Node Segments of Maerua crassifolia

Authors: Abobaker Abrahem M. Saad, Asma Abudasalam

Abstract:

The stem node segments were cultured on Murashige and Skoog (MS) medium. In the case of using MS+ Zeatin (1 mg/l), small shoot buds were formed directly in 70% of explants after 15 days, their length range between 0.1 to 0.3 cm after two weeks and reached 0.3 cm in length and three shoots in numbers after 4 weeks. When those small shoots were sub cultured on the same medium, they increased in length, number and reached 0.4 cm with 4 shoots, 0.4 cm with 5 shoots after six, eight and ten weeks respectively. In the case of using MS free hormones, MS+IAA (0.2mg/l) +BA (0.5mg/l), MS + kin(0.5mg/l), MS + kin (3mg/l) and MS +NAA (3mg/l) +BA (1mg/l), no sign of responses were noticed and only change in color in some cases. Different types of parenchyma cells and many layers of thick wall sclerenchyma cells were observed on MS+BA (1mg/l).

Keywords: Maerua, stem node, shoots, buds, In vitro

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3016 The ‘Quartered Head Technique’: A Simple, Reliable Way of Maintaining Leg Length and Offset during Total Hip Arthroplasty

Authors: M. Haruna, O. O. Onafowokan, G. Holt, K. Anderson, R. G. Middleton

Abstract:

Background: Requirements for satisfactory outcomes following total hip arthroplasty (THA) include restoration of femoral offset, version, and leg length. Various techniques have been described for restoring these biomechanical parameters, with leg length restoration being the most predominantly described. We describe a “quartered head technique” (QHT) which uses a stepwise series of femoral head osteotomies to identify and preserve the centre of rotation of the femoral head during THA in order to ensure reconstruction of leg length, offset and stem version, such that hip biomechanics are restored as near to normal as possible. This study aims to identify whether using the QHT during hip arthroplasty effectively restores leg length and femoral offset to within acceptable parameters. Methods: A retrospective review of 206 hips was carried out, leaving 124 hips in the final analysis. Power analysis indicated a minimum of 37 patients required. All operations were performed using an anterolateral approach by a single surgeon. All femoral implants were cemented, collarless, polished double taper CPT® stems (Zimmer, Swindon, UK). Both cemented, and uncemented acetabular components were used (Zimmer, Swindon, UK). Leg length, version, and offset were assessed intra-operatively and reproduced using the QHT. Post-operative leg length and femoral offset were determined and compared with the contralateral native hip, and the difference was then calculated. For the determination of leg length discrepancy (LLD), we used the method described by Williamson & Reckling, which has been shown to be reproducible with a measurement error of ±1mm. As a reference, the inferior margin of the acetabular teardrop and the most prominent point of the lesser trochanter were used. A discrepancy of less than 6mm LLD was chosen as acceptable. All peri-operative radiographs were assessed by two independent observers. Results: The mean absolute post-operative difference in leg length from the contralateral leg was +3.58mm. 84% of patients (104/124) had LLD within ±6mm of the contralateral limb. The mean absolute post-operative difference in offset from contralateral leg was +3.88mm (range -15 to +9mm, median 3mm). 90% of patients (112/124) were within ±6mm offset of the contralateral limb. There was no statistical difference noted between observer measurements. Conclusion: The QHT provides a simple, inexpensive yet effective method of maintaining femoral leg length and offset during total hip arthroplasty. Combining this technique with pre-operative templating or other techniques described may enable surgeons to reduce even further the discrepancies between pre-operative state and post-operative outcome.

Keywords: leg length discrepancy, technical tip, total hip arthroplasty, operative technique

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3015 Channel Length Modulation Effect on Monolayer Graphene Nanoribbon Field Effect Transistor

Authors: Mehdi Saeidmanesh, Razali Ismail

Abstract:

Recently, Graphene Nanoribbon Field Effect Transistors (GNR FETs) attract a great deal of attention due to their better performance in comparison with conventional devices. In this paper, channel length Modulation (CLM) effect on the electrical characteristics of GNR FETs is analytically studied and modeled. To this end, the special distribution of the electric potential along the channel and current-voltage characteristic of the device is modeled. The obtained results of analytical model are compared to the experimental data of published works. As a result, it is observable that considering the effect of CLM, the current-voltage response of GNR FET is more realistic.

Keywords: graphene nanoribbon, field effect transistors, short channel effects, channel length modulation

Procedia PDF Downloads 376
3014 A Novel Approach to Design of EDDR Architecture for High Speed Motion Estimation Testing Applications

Authors: T. Gangadhararao, K. Krishna Kishore

Abstract:

Motion Estimation (ME) plays a critical role in a video coder, testing such a module is of priority concern. While focusing on the testing of ME in a video coding system, this work presents an error detection and data recovery (EDDR) design, based on the residue-and-quotient (RQ) code, to embed into ME for video coding testing applications. An error in processing Elements (PEs), i.e. key components of a ME, can be detected and recovered effectively by using the proposed EDDR design. The proposed EDDR design for ME testing can detect errors and recover data with an acceptable area overhead and timing penalty.

Keywords: area overhead, data recovery, error detection, motion estimation, reliability, residue-and-quotient (RQ) code

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3013 Short-Path Near-Infrared Laser Detection of Environmental Gases by Wavelength-Modulation Spectroscopy

Authors: Isao Tomita

Abstract:

The detection of environmental gases, 12CO_2, 13CO_2, and CH_4, using near-infrared semiconductor lasers with a short laser path length is studied by means of wavelength-modulation spectroscopy. The developed system is compact and has high sensitivity enough to detect the absorption peaks of isotopic 13CO_2 of a 3-% CO_2 gas at 2 um with a path length of 2.4 m, where its peak size is two orders of magnitude smaller than that of the ordinary 12CO_2 peaks. In addition, the detection of 12CO_2 peaks of a 385-ppm (0.0385-%) CO_2 gas in the air is made at 2 um with a path length of 1.4 m. Furthermore, in pursuing the detection of an ancient environmental CH_4 gas confined to a bubble in ice at the polar regions, measurements of the absorption spectrum for a trace gas of CH_4 in a small area are attempted. For a 100-% CH_4 gas trapped in a 1 mm^3 glass container, the absorption peaks of CH_4 are obtained at 1.65 um with a path length of 3 mm, and also the gas pressure is extrapolated from the measured data.

Keywords: environmental gases, Near-Infrared Laser Detection, Wavelength-Modulation Spectroscopy, gas pressure

Procedia PDF Downloads 391
3012 Influence of Photophysical Parameters of Photoactive Materials on Exciton Diffusion Length and Diffusion Coefficient in Bulk Heterojunction Organic Solar Cells

Authors: Douglas Yeboah, Jai Singh

Abstract:

It has been experimentally demonstrated that exciton diffusion length in organic solids can be improved by fine-tuning the material parameters that govern exciton transfer. Here, a theoretical study is carried out to support this finding. We have therefore derived expressions for the exciton diffusion length and diffusion coefficient of singlet and triplet excitons using Förster resonance energy transfer and Dexter carrier transfer mechanisms and are plotted as a function of photoluminescence (PL) quantum yield, spectral overlap integral, refractive index and dipole moment of the photoactive material. We found that singlet exciton diffusion length increases with PL quantum yield and spectral overlap integral, and decreases with increase in refractive index. Likewise, the triplet exciton diffusion length increases when PL quantum yield increases and dipole moment decreases. The calculated diffusion lengths in different organic materials are compared with existing experimental values and found to be in reasonable agreement. The results are expected to provide insight in developing new organic materials for fabricating bulk heterojunction (BHJ) organic solar cells (OSCs) with better photoconversion efficiency.

Keywords: Dexter carrier transfer, diffusion coefficient, exciton diffusion length, Föster resonance energy transfer, photoactive materials, photophysical parameters

Procedia PDF Downloads 298
3011 Numerical Investigation of the Diffuser: Geometrical Parameters Effect on Flow Characteristics for Diffuser Augmented Wind Turbine

Authors: Hany El Said Fawaz

Abstract:

This study deals with numerical simulation using a commercial package 'ANSYS FLUENT 14.5' for flow characteristics of a flanged diffuser wind turbine. Influence of geometrical parameters such as flange height, diffuser length, and expansion angle on the lift and drag performance were investigated. As the angle of expansion increases, a considerable flow acceleration through the diffuser occur at expansion angle ranged from 0° and 12° due to the presence of undisturbed streamlines. after that flow circulation is developed near the diffuser outlet and increase with increasing expansion angle which causes a negligible effect of expansion angle. The effect of diffuser length on flow behavior shows that when the diffuser length ratio is less than 1.25, flow acceleration is observed and increased with diffuser length ratio. After this value, the flow field at diffuser outlet is characterized by a recirculation zone. The diffuser flange has an impact effect of the flow behavior as a low pressure zone is developed behind the flange, while a high pressure zone is generated in front of it. As the flange height increase, the intensity of both low and high pressure regions increase which tend to accelerate the flow inside the diffuser till flange height ratio reaches to 0.75.

Keywords: wind turbine, flanged diffuser, expansion angle, diffuser length

Procedia PDF Downloads 213