Search results for: strain based approach
Commenced in January 2007
Frequency: Monthly
Edition: International
Paper Count: 36544

Search results for: strain based approach

35164 Rice Serine/Threonine Kinase 1 Is Required for the Stimulation of OsNug2 GTPase Activity

Authors: Jae Bok Heo, Yun Mi Lee, Hee Rang Yun

Abstract:

Several GTPases are required for ribosome biogenesis and assembly. We recently characterized rice (Oryza sativa) nuclear/nucleolar GTPase 2 (OsNug2), belonging to the YlqF/YawG family of GTPases, as playing a role in pre-60S ribosomal subunit maturation. To investigate the potential factors involved in regulating the function of OsNug2, yeast two-hybrid screens were carried out using OsNug2 as bait. Rice serine/threonine kinase 1 (OsSTK1) was identified as a potential interacting protein candidate. In vitro pull down and bimolecular fluorescence complementation assays confirmed the interaction between OsNug2 and OsSTK1, and like green fluorescent protein-tagged OsNug2, green fluorescent protein-tagged OsSTK1 was targeted to the nucleus of Arabidopsis protoplasts. OsSTK1 was not found to affect the GTP-binding activity of OsNug2; however, when recombinant OsSTK1 was included in OsNug2 assay reaction mixtures, OsSTK1 increased the GTPase activity of OsNug2. To test whether OsSTK1 phosphorylates OsNug2 in vitro, a kinase assay was performed. OsSTK1 was found to have weak autophosphorylation activity and strongly phosphorylated serine 209 of OsNug2. Yeast complementation testing resulted in a GAL::OsNug2(S209N) mutant-harboring yeast strain exhibiting a growth-defective phenotype on galactose medium at 39°C, divergent from that of a yeast strain harboring GAL::OsNug2. The intrinsic GTPase activity of mutant OsNug2(S209N) was found to be similar to that of OsNug2, was not fully enhanced upon weak binding of OsSTK1. Our findings reported here indicate that OsSTK1 functions as a positive regulator protein of OsNug2 by enhancing the GTPase activity of OsNug2, and that the phosphorylation of serine 209 of OsNug2 is essential for the complete function of OsNug2 in ribosome biogenesis.

Keywords: OsSTK1, OsNug2, GTPase activity, GTP binding activity, phosphorylation

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35163 Insecticidal Activity of Bacillus Thuringiensis Strain AH-2 Against Hemiptera Insects Pests: Aphis. Gossypii, and Lepidoptera Insect Pests: Plutella Xylostella and Hyphantria Cunea

Authors: Ajuna B. Henry

Abstract:

In recent decades, climate change has demanded biological pesticides; more Bt strains are being discovered worldwide, some containing novel insecticidal genes while others have been modified through molecular approaches for increased yield, toxicity, and wider host target. In this study, B. thuringiensis strain AH-2 (Bt-2) was isolated from the soil and tested for insecticidal activity against Aphis gossypii (Hemiptera: Aphididae) and Lepidoptera insect pests: fall webworm (Hyphantria cunea) and diamondback moth (Plutella xylostella). A commercial strain B. thuringiensis subsp. kurstaki (Btk), and a chemical pesticide, imidacloprid (for Hemiptera) and chlorantraniliprole (for Lepidoptera), were used as positive control and the same media (without bacterial inoculum) as a negative control. For aphidicidal activity, Bt-2 caused a mortality rate of 70.2%, 78.1% or 88.4% in third instar nymphs of A. gossypii (3N) at 10%, 25% or 50% culture concentrations, respectively. Moreover, Bt-2 was effectively produced in cost-effective (PB) supplemented with either glucose (PBG) or sucrose (PBS) and maintained high aphicidal efficacy with 3N mortality rates of 85.9%, 82.9% or 82.2% in TSB, PBG or PBS media, respectively at 50% culture concentration. Bt-2 also suppressed adult fecundity by 98.3% compared to only 65.8% suppression by Btk at similar concentrations but was slightly lower than chemical treatment, which caused 100% suppression. Partial purification of 60 – 80% (NH4)2SO4 fraction of Bt-2 aphicidal proteins purified on anion exchange (DEAE-FF) column revealed a 105 kDa aphicidal protein with LC50 = 55.0 ng/µℓ. For Lepidoptera pests, chemical pesticide, Bt-2, and Btk cultures, mortality of 86.7%, 60%, and 60% in 3rd instar larvae of P. xylostella, and 96.7%, 80.0%, and 93.3% in 6th instar larvae of H. cunea, after 72h of exposure. When the entomopathogenic strains were cultured in a cost-effective PBG or PBS, the insecticidal activity in all strains was not significantly different compared to the use of a commercial medium (TSB). Bt-2 caused a mortality rate of 60.0%, 63.3%, and 50.0% against P. xylostella larvae and 76.7%, 83.3%, and 73.3% against H. cunea when grown in TSB, PBG, and PBS media, respectively. Bt-2 (grown in cost-effective PBG medium) caused a dose-dependent toxicity of 26.7%, 40.0%, and 63.3% against P. xylostella and 46.7%, 53.3%, and 76.7% against H. cunea at 10%, 25% and 50% culture concentration, respectively. The partially purified Bt-2 insecticidal proteins fractions F1, F2, F3, and F4 (extracted at different ratios of organic solvent) caused low toxicity (50.0%, 40.0%, 36.7%, and 30.0%) against P. xylostella and relatively high toxicity (56.7%, 76.7%, 66.7%, and 63.3%) against H. cunea at 100 µg/g of artificial diets. SDS-PAGE analysis revealed that a128kDa protein is associated with toxicity of Bt-2. Our result demonstrates a medium and strong larvicidal activity of Bt-2 against P. xylostella and H. cunea, respectively. Moreover, Bt-2 could be potentially produced using a cost-effective PBG medium which makes it an effective alternative biocontrol strategy to reduce chemical pesticide application.

Keywords: biocontrol, insect pests, larvae/nymph mortality, cost-effective media, aphis gossypii, plutella xylostella, hyphantria cunea, bacillus thuringiensi

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35162 Effect of Thickness on Structural and Electrical Properties of CuAlS2 Thin Films Grown by Two Stage Vacuum Thermal Evaporation Technique

Authors: A. U. Moreh, M. Momoh, H. N. Yahya, B. Hamza, I. G. Saidu, S. Abdullahi

Abstract:

This work studies the effect of thickness on structural and electrical properties of CuAlS2 thin films grown by two stage vacuum thermal evaporation technique. CuAlS2 thin films of thicknesses 50nm, 100nm and 200nm were deposited on suitably cleaned corning 7059 glass substrate at room temperature (RT). In the first stage Cu-Al precursors were grown at room temperature by thermal evaporation and in the second stage Cu-Al precursors were converted to CuAlS2 thin films by sulfurisation under sulfur atmosphere at the temperature of 673K. The structural properties of the films were examined by X-ray diffraction (XRD) technique while electrical properties of the specimens were studied using four point probe method. The XRD studies revealed that the films are of crystalline in nature having tetragonal structure. The variations of the micro-structural parameters, such as crystallite size (D), dislocation density ( ), and micro-strain ( ), with film thickness were investigated. The results showed that the crystallite sizes increase as the thickness of the film increases. The dislocation density and micro-strain decreases as the thickness increases. The resistivity (  ) of CuAlS2 film is found to decrease with increase in film thickness, which is related to the increase of carrier concentration with film thickness. Thus thicker films exhibit the lowest resistivity and high carrier concentration, implying these are the most conductive films. Low electrical resistivity and high carrier concentration are widely used as the essential components in various optoelectronic devices such as light-emitting diode and photovoltaic cells.

Keywords: CuAlS2, evaporation, sulfurisation, thickness, resistivity, crystalline

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35161 Implementation of the Collaborative Learning Approach in Learning of Second Language English

Authors: Ashwini Mahesh Jagatap

Abstract:

This paper presents the language learning strategy with respect to speaking skill with collaborative learning approach. Collaborative learning has been proven to be efficient learning methodology for all kinds of students. Students are working in groups of two or more, reciprocally searching for understanding, Solutions, or meanings, or creating a product. The presentation highlights the different stages which can be implemented during actual implementation of the methodology in the class room teaching learning process.

Keywords: collaborative classroom, collaborative learning approach, language skills, traditional teaching

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35160 Robust Model Predictive Controller for Uncertain Nonlinear Wheeled Inverted Pendulum Systems: A Tube-Based Approach

Authors: Tran Gia Khanh, Dao Phuong Nam, Do Trong Tan, Nguyen Van Huong, Mai Xuan Sinh

Abstract:

This work presents the problem of tube-based robust model predictive controller for a class of continuous-time systems in the presence of input disturbances. The main objective is to point out the state trajectory of closed system being maintained inside a sequence of tubes. An estimation of attraction region of the closed system is pointed out based on input state stability (ISS) theory and linearized model in each time interval. The theoretical analysis and simulation results demonstrate the performance of the proposed algorithm for a wheeled inverted pendulum system.

Keywords: input state stability (ISS), tube-based robust MPC, continuous-time nonlinear systems, wheeled inverted pendulum

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35159 Reconstruction of Performace-Based Budgeting in Indonesian Local Government: Application of Soft Systems Methodology in Producing Guideline for Policy Implementation

Authors: Deddi Nordiawan

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Effective public policy creation required a strong budget system, both in terms of design and implementation. Performance-based Budget is an evolutionary approach with two substantial characteristics; first, the strong integration between budgeting and planning, and second, its existence as guidance so that all activities and expenditures refer to measurable performance targets. There are four processes in the government that should be followed in order to make the budget become performance-based. These four processes consist of the preparation of a vision according to the bold aspiration, the formulation of outcome, the determination of output based on the analysis of organizational resources, and the formulation of Value Creation Map that contains a series of programs and activities. This is consistent with the concept of logic model which revealed that the budget performance should be placed within a relational framework of resources, activities, outputs, outcomes and impacts. Through the issuance of Law 17/2003 regarding State Finance, local governments in Indonesia have to implement performance-based budget. Central Government then issued Government Regulation 58/2005 which contains the detail guidelines how to prepare local governments budget. After a decade, implementation of performance budgeting in local government is still not fully meet expectations, though the guidance is completed, socialization routinely performed, and trainings have also been carried out at all levels. Accordingly, this study views the practice of performance-based budget at local governments as a problematic situation. This condition must be approached with a system approach that allows the solutions from many point of views. Based on the fact that the infrastructure of budgeting has already settled, the study then considering the situation as complexity. Therefore, the intervention needs to be done in the area of human activity system. Using Soft Systems Methodology, this research will reconstruct the process of performance-based budget at local governments is area of human activity system. Through conceptual models, this study will invite all actors (central government, local government, and the parliament) for dialogue and formulate interventions in human activity systems that systematically desirable and culturally feasible. The result will direct central government in revise the guidance to local government budgeting process as well as a reference to build the capacity building strategy.

Keywords: soft systems methodology, performance-based budgeting, Indonesia, public policy

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35158 Evaluation of Deformable Boundary Condition Using Finite Element Method and Impact Test for Steel Tubes

Authors: Abed Ahmed, Mehrdad Asadi, Jennifer Martay

Abstract:

Stainless steel pipelines are crucial components to transportation and storage in the oil and gas industry. However, the rise of random attacks and vandalism on these pipes for their valuable transport has led to more security and protection for incoming surface impacts. These surface impacts can lead to large global deformations of the pipe and place the pipe under strain, causing the eventual failure of the pipeline. Therefore, understanding how these surface impact loads affect the pipes is vital to improving the pipes’ security and protection. In this study, experimental test and finite element analysis (FEA) have been carried out on EN3B stainless steel specimens to study the impact behaviour. Low velocity impact tests at 9 m/s with 16 kg dome impactor was used to simulate for high momentum impact for localised failure. FEA models of clamped and deformable boundaries were modelled to study the effect of the boundaries on the pipes impact behaviour on its impact resistance, using experimental and FEA approach. Comparison of experimental and FE simulation shows good correlation to the deformable boundaries in order to validate the robustness of the FE model to be implemented in pipe models with complex anisotropic structure.

Keywords: dynamic impact, deformable boundary conditions, finite element modelling, LS-DYNA, stainless steel pipe

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35157 A Unified Approach to Support the Coordination of Usability Work in Agile Software Development

Authors: Fouad Abdulameer Salman, Aziz Bin Deraman, Masita Binti Abdul Jalil

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Usability evaluation is essential for developing usable software systems, yet its integration within agile software development remains a challenging interdisciplinary endeavour. In this paper, the authors present a study to investigate obstacles of such integration from the management perspective. The study incorporates two methods, namely an online questionnaire survey and a series of interviews with participants that answered the questionnaire. Based on the obtained results, a unified approach is proposed for enabling coordinate the efforts of agile developers and usability engineers to produce usable software systems.

Keywords: usability, usability evaluation, software development process, usability management

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35156 Bridging the Data Gap for Sexism Detection in Twitter: A Semi-Supervised Approach

Authors: Adeep Hande, Shubham Agarwal

Abstract:

This paper presents a study on identifying sexism in online texts using various state-of-the-art deep learning models based on BERT. We experimented with different feature sets and model architectures and evaluated their performance using precision, recall, F1 score, and accuracy metrics. We also explored the use of pseudolabeling technique to improve model performance. Our experiments show that the best-performing models were based on BERT, and their multilingual model achieved an F1 score of 0.83. Furthermore, the use of pseudolabeling significantly improved the performance of the BERT-based models, with the best results achieved using the pseudolabeling technique. Our findings suggest that BERT-based models with pseudolabeling hold great promise for identifying sexism in online texts with high accuracy.

Keywords: large language models, semi-supervised learning, sexism detection, data sparsity

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35155 Entrepreneurial Ecosystems and Innovation Systems: An Appraisal of Literature

Authors: Jose Carlos Rodriguez, Mario Gomez

Abstract:

In the last years, the concept of entrepreneurial ecosystems has gained popularity. It reveals the importance of a supportive community and adequate economic environment for entrepreneurial activity, and thus the possibility of developing a different perspective on the innovation system. On the other hand, the (regional/technology) innovation system approach lacks in its analyses the presence of an entrepreneur as a key actor that develops innovations. In this regard, this paper examines the foundations of both theoretical approaches (the entrepreneurial ecosystems and the regional/technology systems of innovation) and their contributions to understand entrepreneurial activity at different levels of analyses, namely national, regional or local. The paper makes a literature review on both perspectives of innovation stressing the role played by entrepreneurs in these theoretical approaches. It concludes remarking that the regional/technology innovation systems approach and the entrepreneurial ecosystem approach have established themselves in their own right, but the regional/technology innovation system approach is a predecessor of the entrepreneurial ecosystem approach.

Keywords: entrepreneurial ecosystems, innovation systems, entrepreneurial activity, comparative analysis

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35154 Intelligent Control of Bioprocesses: A Software Application

Authors: Mihai Caramihai, Dan Vasilescu

Abstract:

The main research objective of the experimental bioprocess analyzed in this paper was to obtain large biomass quantities. The bioprocess is performed in 100 L Bioengineering bioreactor with 42 L cultivation medium made of peptone, meat extract and sodium chloride. The reactor was equipped with pH, temperature, dissolved oxygen, and agitation controllers. The operating parameters were 37 oC, 1.2 atm, 250 rpm and air flow rate of 15 L/min. The main objective of this paper is to present a case study to demonstrate that intelligent control, describing the complexity of the biological process in a qualitative and subjective manner as perceived by human operator, is an efficient control strategy for this kind of bioprocesses. In order to simulate the bioprocess evolution, an intelligent control structure, based on fuzzy logic has been designed. The specific objective is to present a fuzzy control approach, based on human expert’ rules vs. a modeling approach of the cells growth based on bioprocess experimental data. The kinetic modeling may represent only a small number of bioprocesses for overall biosystem behavior while fuzzy control system (FCS) can manipulate incomplete and uncertain information about the process assuring high control performance and provides an alternative solution to non-linear control as it is closer to the real world. Due to the high degree of non-linearity and time variance of bioprocesses, the need of control mechanism arises. BIOSIM, an original developed software package, implements such a control structure. The simulation study has showed that the fuzzy technique is quite appropriate for this non-linear, time-varying system vs. the classical control method based on a priori model.

Keywords: intelligent, control, fuzzy model, bioprocess optimization

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35153 Web-Based Alcohol Prevention among Iranian Medical University Students: A Randomized Control Trail

Authors: Farzad Jalilian, Mehdi Mirzaei Alavijeh

Abstract:

Background: E-interventions as a universal approach to prevent a high-risk behavior, such as alcohol drinking. This study was conducted to evaluate web-based alcohol drinking preventative intervention efficiency among medical university students in Iran. Methods: Overall, 150 freshman and sophomore male student’s college students participated in this study as intervention and control group. This was a longitudinal randomized pre- and post-test series control group design panel study to implement a behavior modification based intervention to alcohol drinking prevention among college students. Cross-tabulation, t-test, repeated measures, and GEE by using SPSS statistical package, version 21 was used for the statistical analysis. The participants were followed up for 6 months with data collection scheduled at baseline, 3 and 6 months. The primary outcomes are attitude, self-control, and sensation seeking. Furthermore, the secondary outcome is comparing alcohol drinking among the study groups. Results: It was found significant reduce in average response for an attitude towards alcohol drinking and sensation seeking among intervention group (P < 0.05). But after intervention not significant difference between intervention and control group of improve self-control and reduce alcohol drinking (P > 0.05). Conclusion: Our intervention has been accompanied with reducing alcohol use rate. These findings indicate that e-intervention may be effectiveness approach to address the alcohol prevention among college students.

Keywords: e-interventions, alcohol drinking, students, Iran

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35152 Predicting the Success of Bank Telemarketing Using Artificial Neural Network

Authors: Mokrane Selma

Abstract:

The shift towards decision making (DM) based on artificial intelligence (AI) techniques will change the way in which consumer markets and our societies function. Through AI, predictive analytics is being used by businesses to identify these patterns and major trends with the objective to improve the DM and influence future business outcomes. This paper proposes an Artificial Neural Network (ANN) approach to predict the success of telemarketing calls for selling bank long-term deposits. To validate the proposed model, we uses the bank marketing data of 41188 phone calls. The ANN attains 98.93% of accuracy which outperforms other conventional classifiers and confirms that it is credible and valuable approach for telemarketing campaign managers.

Keywords: bank telemarketing, prediction, decision making, artificial intelligence, artificial neural network

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35151 Convergence Analysis of a Gibbs Sampling Based Mix Design Optimization Approach for High Compressive Strength Pervious Concrete

Authors: Jiaqi Huang, Lu Jin

Abstract:

Pervious concrete features with high water permeability rate. However, due to the lack of fine aggregates, the compressive strength is usually lower than other conventional concrete products. Optimization of pervious concrete mix design has long been recognized as an effective mechanism to achieve high compressive strength while maintaining desired permeability rate. In this paper, a Gibbs Sampling based algorithm is proposed to approximate the optimal mix design to achieve a high compressive strength of pervious concrete. We prove that the proposed algorithm efficiently converges to the set of global optimal solutions. The convergence rate and accuracy depend on a control parameter employed in the proposed algorithm. The simulation results show that, by using the proposed approach, the system converges to the optimal solution quickly and the derived optimal mix design achieves the maximum compressive strength while maintaining the desired permeability rate.

Keywords: convergence, Gibbs Sampling, high compressive strength, optimal mix design, pervious concrete

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35150 Vision-Based Hand Segmentation Techniques for Human-Computer Interaction

Authors: M. Jebali, M. Jemni

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This work is the part of vision based hand gesture recognition system for Natural Human Computer Interface. Hand tracking and segmentation are the primary steps for any hand gesture recognition system. The aim of this paper is to develop robust and efficient hand segmentation algorithm such as an input to another system which attempt to bring the HCI performance nearby the human-human interaction, by modeling an intelligent sign language recognition system based on prediction in the context of dialogue between the system (avatar) and the interlocutor. For the purpose of hand segmentation, an overcoming occlusion approach has been proposed for superior results for detection of hand from an image.

Keywords: HCI, sign language recognition, object tracking, hand segmentation

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35149 Design Improvement of Worm Gearing for Better Energy Utilization

Authors: Ahmed Elkholy

Abstract:

Most power transmission cases use gearing in general, and worm gearing, in particular for energy utilization. Therefore, designing gears for minimum weight and maximum power transmission is the main target of this study. In this regard, a new approach has been developed to estimate the load share and stress distribution of worm gear sets. The approach is based upon considering the instantaneous tooth meshing stiffness where the worm gear drive was modelled as a series of spur gear slices, and each slice was analyzed separately using a well-established criteria. By combining the results obtained for all slices, the entire worm gear set loading and stressing was determined. The geometric modelling method presented, allows tooth elastic deformation and tooth root stresses of worm gear drives under different load conditions to be investigated. On the basis of the method introduced in this study, the instantaneous meshing stiffness and load share were obtained. In comparison with existing methods, this approach has both good analytical accuracy and less computing time.

Keywords: gear, load/stress distribution, worm, wheel, tooth stiffness, contact line

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35148 Product Feature Modelling for Integrating Product Design and Assembly Process Planning

Authors: Baha Hasan, Jan Wikander

Abstract:

This paper describes a part of the integrating work between assembly design and assembly process planning domains (APP). The work is based, in its first stage, on modelling assembly features to support APP. A multi-layer architecture, based on feature-based modelling, is proposed to establish a dynamic and adaptable link between product design using CAD tools and APP. The proposed approach is based on deriving “specific function” features from the “generic” assembly and form features extracted from the CAD tools. A hierarchal structure from “generic” to “specific” and from “high level geometrical entities” to “low level geometrical entities” is proposed in order to integrate geometrical and assembly data extracted from geometrical and assembly modelers to the required processes and resources in APP. The feature concept, feature-based modelling, and feature recognition techniques are reviewed.

Keywords: assembly feature, assembly process planning, feature, feature-based modelling, form feature, ontology

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35147 Embedding the Dimensions of Sustainability into City Information Modelling

Authors: Ali M. Al-Shaery

Abstract:

The purpose of this paper is to address the functions of sustainability dimensions in city information modelling and to present the required sustainability criteria that support establishing a sustainable planning framework for enhancing existing cities and developing future smart cities. The paper is divided into two sections. The first section is based on the examination of a wide and extensive array of cross-disciplinary literature in the last decade and a half to conceptualize the terms ‘sustainable’ and ‘smart city,' and map their associated criteria to city information modelling. The second section is based on analyzing two approaches relating to city information modelling, namely statistical and dynamic approaches, and their suitability in the development of cities’ action plans. The paper argues that the use of statistical approaches to embedding sustainability dimensions in city information modelling have limited value. Despite the popularity of such approaches in addressing other dimensions like utility and service management in development and action plans of the world cities, these approaches are unable to address the dynamics across various city sectors with regards to economic, environmental and social criteria. The paper suggests an integrative dynamic and cross-disciplinary planning approach to embedding sustainability dimensions in city information modelling frameworks. Such an approach will pave the way towards optimal planning and implementation of priority actions of projects and investments. The approach can be used to achieve three main goals: (1) better development and action plans for world cities (2) serve the development of an integrative dynamic and cross-disciplinary framework that incorporates economic, environmental and social sustainability criteria and (3) address areas that require further attention in the development of future sustainable and smart cities. The paper presents an innovative approach for city information modelling and a well-argued, balanced hierarchy of sustainability criteria that can contribute to an area of research which is still in its infancy in terms of development and management.

Keywords: information modelling, smart city, sustainable city, sustainability dimensions, sustainability criteria, city development planning

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35146 Enhancement of Mechanical and Dissolution Properties of a Cast Magnesium Alloy via Equal Angular Channel Processing

Authors: Tim Dunne, Jiaxiang Ren, Lei Zhao, Peng Cheng, Yi Song, Yu Liu, Wenhan Yue, Xiongwen Yang

Abstract:

Two decades of the Shale Revolution has transforming transformed the global energy market, in part by the adaption of multi-stage dissolvable frac plugs. Magnesium has been favored for the bulk of plugs, requiring development of materials to suit specific field requirements. Herein, the mechanical and dissolution results from equal channel angular pressing (ECAP) of two cast dissolvable magnesium alloy are described. ECAP was selected as a route to increase the mechanical properties of two formulations of dissolvable magnesium, as solutionizing failed. In this study, 1” square cross section samples cast Mg alloys formulations containing rare earth were processed at temperatures ranging from 200 to 350 °C, at a rate of 0.005”/s, with a backpressure from 0 to 70 MPa, in a brass, or brass + graphite sheet. Generally, the yield and ultimate tensile strength (UTS) doubled for all. For formulation DM-2, the yield increased from 100 MPa to 250 MPa; UTS from 175 MPa to 325 MPa, but the strain fell from 2 to 1%. Formulation DM-3 yield increased from 75 MPa to 200 MPa, UTS from 150 MPa to 275 MPa, with strain increasing from 1 to 3%. Meanwhile, ECAP has also been found to reduce the dissolution rate significantly. A microstructural analysis showed grain refinement of the alloy and the movement of secondary phases away from the grain boundary. It is believed that reconfiguration of the grain boundary phases increased the mechanical properties and decreased the dissolution rate. ECAP processing of dissolvable high rare earth content magnesium is possible despite the brittleness of the material. ECAP is a possible processing route to increase mechanical properties for dissolvable aluminum alloys that do not extrude.

Keywords: equal channel angular processing, dissolvable magnesium, frac plug, mechanical properties

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35145 Hybrid Collaborative-Context Based Recommendations for Civil Affairs Operations

Authors: Patrick Cummings, Laura Cassani, Deirdre Kelliher

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In this paper we present findings from a research effort to apply a hybrid collaborative-context approach for a system focused on Marine Corps civil affairs data collection, aggregation, and analysis called the Marine Civil Information Management System (MARCIMS). The goal of this effort is to provide operators with information to make sense of the interconnectedness of entities and relationships in their area of operation and discover existing data to support civil military operations. Our approach to build a recommendation engine was designed to overcome several technical challenges, including 1) ensuring models were robust to the relatively small amount of data collected by the Marine Corps civil affairs community; 2) finding methods to recommend novel data for which there are no interactions captured; and 3) overcoming confirmation bias by ensuring content was recommended that was relevant for the mission despite being obscure or less well known. We solve this by implementing a combination of collective matrix factorization (CMF) and graph-based random walks to provide recommendations to civil military operations users. We also present a method to resolve the challenge of computation complexity inherent from highly connected nodes through a precomputed process.

Keywords: Recommendation engine, collaborative filtering, context based recommendation, graph analysis, coverage, civil affairs operations, Marine Corps

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35144 A Segmentation Method for Grayscale Images Based on the Firefly Algorithm and the Gaussian Mixture Model

Authors: Donatella Giuliani

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In this research, we propose an unsupervised grayscale image segmentation method based on a combination of the Firefly Algorithm and the Gaussian Mixture Model. Firstly, the Firefly Algorithm has been applied in a histogram-based research of cluster means. The Firefly Algorithm is a stochastic global optimization technique, centered on the flashing characteristics of fireflies. In this context it has been performed to determine the number of clusters and the related cluster means in a histogram-based segmentation approach. Successively these means are used in the initialization step for the parameter estimation of a Gaussian Mixture Model. The parametric probability density function of a Gaussian Mixture Model is represented as a weighted sum of Gaussian component densities, whose parameters are evaluated applying the iterative Expectation-Maximization technique. The coefficients of the linear super-position of Gaussians can be thought as prior probabilities of each component. Applying the Bayes rule, the posterior probabilities of the grayscale intensities have been evaluated, therefore their maxima are used to assign each pixel to the clusters, according to their gray-level values. The proposed approach appears fairly solid and reliable when applied even to complex grayscale images. The validation has been performed by using different standard measures, more precisely: the Root Mean Square Error (RMSE), the Structural Content (SC), the Normalized Correlation Coefficient (NK) and the Davies-Bouldin (DB) index. The achieved results have strongly confirmed the robustness of this gray scale segmentation method based on a metaheuristic algorithm. Another noteworthy advantage of this methodology is due to the use of maxima of responsibilities for the pixel assignment that implies a consistent reduction of the computational costs.

Keywords: clustering images, firefly algorithm, Gaussian mixture model, meta heuristic algorithm, image segmentation

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35143 The Genus Bacillus, Effect on Commercial Crops of Colombia

Authors: L. C. Sánchez, L. C. Corrales, A. G. Lancheros, E. Castañeda, Y. Ariza, L. S. Fuentes, L. Sierra, J. L. Cuervo

Abstract:

The importance of environment friendly alternatives in agricultural processes is the reason why the research group Ceparium, the Colegio Mayor de Cundinamarca University, Colombia, investigated the genus Bacillus and its applicability for improving crops of economic importance in Colombia. In this investigation, we presented a study in which the genus Bacillus plays a leading role as beneficial microorganism. The objective was to identify the biochemical potential of three indigenous species of Bacillus, which were able to carry out actions for biological control against pathogens and pests or promoted growth to improve productivity of crops in Colombia. The procedures were performed in three phases: first, the production of biomass of an indigenous strain and a reference strain starting from culture media for production of spores and toxins were made. Spore count was done in a Neubauer chamber, concentrations of spores of Bacillus sphaericus were prepared and a bioassay was done at the Laboratory of Entomology at the University Jorge Tadeo Lozano of Plutella xylostella larvae, insect pest of crucifers in several Colombian regions. The second phase included the extraction in the liquid state fermentation, a secondary metabolite that has antibiosis action against fungi, call iturin B, and was obtained from strains of Bacillus subtilis. The molecule was identified using High Resolution Chromatography (HPLC) and its biocontrol effect on Fusarium sp fungus causes vascular wilt in economically important plant varieties, was confirmed using testing of antagonism in Petri dish. In the third phase, an initial procedure in that let recover and identify microorganisms of the genus Bacillus from the rhizosphere in two aromatic herbs, Rosmarinus officinalis and Thymus vulgaris L. was used. Subsequently, testing of antagonism against Fusarium sp were made and an assay was done under greenhouse conditions to observe biocontrol and growth promoting action by comparing growth in length and dry weight. In the first experiment, native Bacillus sphaericus was lethal to 92% Plutella xylostella larvae in 10 DDA. In the second experiment, iturin B was identified and biological control of Fusarium sp was demonstrated. In the third study, all strains demonstrated biological control and the B14 strain identified as Bacillus megaterium increased root length and productivity of the two plants in terms of weight. It was concluded that the native microorganisms of the genus Bacillus has a great biochemical potential that provides a beneficial interactions with plants, improve their growth and development and therefore a greater impact on production.

Keywords: genus bacillus, biological control, PGPRs, biochemical potential

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35142 A Novel Approach of NPSO on Flexible Logistic (S-Shaped) Model for Software Reliability Prediction

Authors: Pooja Rani, G. S. Mahapatra, S. K. Pandey

Abstract:

In this paper, we propose a novel approach of Neural Network and Particle Swarm Optimization methods for software reliability prediction. We first explain how to apply compound function in neural network so that we can derive a Flexible Logistic (S-shaped) Growth Curve (FLGC) model. This model mathematically represents software failure as a random process and can be used to evaluate software development status during testing. To avoid trapping in local minima, we have applied Particle Swarm Optimization method to train proposed model using failure test data sets. We drive our proposed model using computational based intelligence modeling. Thus, proposed model becomes Neuro-Particle Swarm Optimization (NPSO) model. We do test result with different inertia weight to update particle and update velocity. We obtain result based on best inertia weight compare along with Personal based oriented PSO (pPSO) help to choose local best in network neighborhood. The applicability of proposed model is demonstrated through real time test data failure set. The results obtained from experiments show that the proposed model has a fairly accurate prediction capability in software reliability.

Keywords: software reliability, flexible logistic growth curve model, software cumulative failure prediction, neural network, particle swarm optimization

Procedia PDF Downloads 341
35141 Postbuckling Analysis of End Supported Rods under Self-Weight Using Intrinsic Coordinate Finite Elements

Authors: C. Juntarasaid, T. Pulngern, S. Chucheepsakul

Abstract:

A formulation of postbuckling analysis of end supported rods under self-weight has been presented by the variational method. The variational formulation involving the strain energy due to bending and the potential energy of the self-weight, are expressed in terms of the intrinsic coordinates. The variational formulation is accomplished by introducing the Lagrange multiplier technique to impose the boundary conditions. The finite element method is used to derive a system of nonlinear equations resulting from the stationary of the total potential energy and then Newton-Raphson iterative procedure is applied to solve this system of equations. The numerical results demonstrate the postbluckled configurations of end supported rods under self-weight. This finite element method based on variational formulation expressed in term of intrinsic coordinate is highly recommended for postbuckling analysis of end-supported rods under self-weight.

Keywords: postbuckling, finite element method, variational method, intrinsic coordinate

Procedia PDF Downloads 154
35140 Concrete Cracking Simulation Using Vector Form Intrinsic Finite Element Method

Authors: R. Z. Wang, B. C. Lin, C. H. Huang

Abstract:

This study proposes a new method to simulate the crack propagation under mode-I loading using Vector Form Intrinsic Finite Element (VFIFE) method. A new idea which is expected to combine both VFIFE and J-integral is proposed to calculate the stress density factor as the crack critical in elastic crack. The procedure of implement the cohesive crack propagation in VFIFE based on the fictitious crack model is also proposed. In VFIFIE, the structure deformation is described by numbers of particles instead of elements. The strain energy density and the derivatives of the displacement vector of every particle is introduced to calculate the J-integral as the integral path is discrete by particles. The particle on the crack tip separated into two particles once the stress on the crack tip satisfied with the crack critical and then the crack tip propagates to the next particle. The internal force and the cohesive force is applied to the particles.

Keywords: VFIFE, crack propagation, fictitious crack model, crack critical

Procedia PDF Downloads 332
35139 Implications of Fuel Reloading in Heterogeneous Thorium-Based Fuel Designs for Improved Fuel Cycle Characteristics

Authors: Hendrik Bernard Van Der Walt, Frik Van Niekerk

Abstract:

Fuel models render a reduction in BOL when thorium is added to a reactor core. Thorium emulates the role of a fertile poison, and is beneficial for reducing beginning of cycle (BOC) excess reactivity. In spite of the build-up of 233U over the duration of a fuel cycle, the effects of fuel reloading have a significant impact on fuel viability, especially in the case of heterogeneous thorium-based fuels. The most common practice of compensating for the reduction of BOC reactivity is the addition of fissile isotopes (uranium fuel with increased enrichment or plutonium). This study introduces a heterogeneous thorium-based fuel with minimal fissile isotope additions. A pseudo reloading scheme was developed for numerical simulations of an infinite reactor based on the North-Anna 1 reactor operating in Virginia, USA. Use of this reloading pattern allows new thorium-based fuel to be loaded into the reactor model as part of a phasing in strategy at the end of any conventional reactor cycle. Results demonstrate the effects of thorium-based fuel on fuel cycle characteristics such as fuel cycle length, neutron economy and material matrix. Application of the above mentioned approach delivered promising results and presents a heterogeneous thorium-based fuel which could replace conventional fuel of typical, currently operating (or future) reactors without the need for expensive reactor redesign or fuel recycling strategies.

Keywords: nuclear fuel, nuclear characteristics, nuclear fuel cycle, thorium-based fuel, heterogeneous design, fuel reloading

Procedia PDF Downloads 127
35138 A Bundled Approach to Explaining Technological Change: The Case of E-Estonia

Authors: Andrew Adjah Sai, Portia Opoku Boadi

Abstract:

Explaining change is an abstract endeavor. Many management scholars have adopted metaphors to explain change. In this paper, we deal with the drivers of technological change. We use a historical and theoretical approach to review and elaborate on the concepts and context about a specific case. We discuss the limitations of each approach proffered and the implications as a consequence on technological change. We present plurality and multiplicity of perspectives using a socio-technical approach to explain technological change contextually on an organizational level. We show by using our model how technology absorption and diffusion can be accelerated through artefactual institutions to enable social change. The multiplicity of perspectives and plurality of our arguments creates a fine explanation of the e-Estonia case as an example.

Keywords: artefactual institutions, e-Estonia, social change, technological trajectories

Procedia PDF Downloads 444
35137 Transforming Butterworth Low Pass Filter into Microstrip Line Form at LC-Band Applications

Authors: Liew Hui Fang, Syed Idris Syed Hassan, Mohd Fareq Abd. Malek, Yufridin Wahab, Norshafinash Saudin

Abstract:

The paper implementation new approach method applied into transforming lumped element circuit into microstrip line form for Butterworth low pass filter which is operating at LC band. The filter’s lumped element circuits and microstrip line form were first designed and simulated using Advanced Design Software (ADS) to obtain the best filter characteristic based on S-parameter and implemented on FR4 substrate for order N=3,4,5,6,7,8 and 9. The importance of a new approach of transforming method as a correction factor has been considered into designed microstrip line. From ADS simulation results proved that the response of microstrip line circuit of Butterworth low pass filter with fringing correction factor has an excellent agreement with its lumped circuit. This shows that the new approach of transforming lumped element circuit into microstrip line is able to solve the conventional design of complexity size of circuit of Butterworth low pass filter (LPF) into microstrip line.

Keywords: Butterworth low pass filter, number of order, microstrip line, microwave filter, maximally flat

Procedia PDF Downloads 330
35136 Reducing Component Stress during Encapsulation of Electronics: A Simulative Examination of Thermoplastic Foam Injection Molding

Authors: Constantin Ott, Dietmar Drummer

Abstract:

The direct encapsulation of electronic components is an effective way of protecting components against external influences. In addition to achieving a sufficient protective effect, there are two other big challenges for satisfying the increasing demand for encapsulated circuit boards. The encapsulation process should be both suitable for mass production and offer a low component load. Injection molding is a method with good suitability for large series production but also with typically high component stress. In this article, two aims were pursued: first, the development of a calculation model that allows an estimation of the occurring forces based on process variables and material parameters. Second, the evaluation of a new approach for stress reduction by means of thermoplastic foam injection molding. For this purpose, simulation-based process data was generated with the Moldflow simulation tool. Based on this, component stresses were calculated with the calculation model. At the same time, this paper provided a model for estimating the forces occurring during overmolding and derived a solution method for reducing these forces. The suitability of this approach was clearly demonstrated and a significant reduction in shear forces during overmolding was achieved. It was possible to demonstrate a process development that makes it possible to meet the two main requirements of direct encapsulation in addition to a high protective effect.

Keywords: encapsulation, stress reduction, foam-injection-molding, simulation

Procedia PDF Downloads 122
35135 Non-Destructive Visual-Statistical Approach to Detect Leaks in Water Mains

Authors: Alaa Al Hawari, Mohammad Khader, Tarek Zayed, Osama Moselhi

Abstract:

In this paper, an effective non-destructive, non-invasive approach for leak detection was proposed. The process relies on analyzing thermal images collected by an IR viewer device that captures thermo-grams. In this study a statistical analysis of the collected thermal images of the ground surface along the expected leak location followed by a visual inspection of the thermo-grams was performed in order to locate the leak. In order to verify the applicability of the proposed approach the predicted leak location from the developed approach was compared with the real leak location. The results showed that the expected leak location was successfully identified with an accuracy of more than 95%.

Keywords: thermography, leakage, water pipelines, thermograms

Procedia PDF Downloads 349