Search results for: objective structure
Commenced in January 2007
Frequency: Monthly
Edition: International
Paper Count: 14140

Search results for: objective structure

12160 Developing a Mathematical Model for Trade-Off Analysis of New Green Products

Authors: M. R. Gholizadeh, N. Bhuiyan, M. Salari

Abstract:

In the near future, companies will be increasingly forced to shift their activities along a new road in order to decrease the harmful effects of their design, production and after-life on our environment. Products must meet environmental standards to not only prevent penalties but to consider the sustainability for future generations. However, the most important factor that companies will face is selecting a reasonable strategy to maximize their profit. Thus, companies need to have precise forecast from their profit after design stage through Trade-off analysis. This paper is an attempt to introduce a mathematical model that considers effective factors that impact the total profit when products are designed for resource and energy efficiency or recyclability. The modification is according to different strategies based on a Cost-Volume-Profit model. Here, the cost structure consists of Recycling cost, Development cost, Ramp-up cost, Production cost, and Pollution cost. Also, the model shows the effect of implementation of design for recyclable on revenue structure through revenue of used parts and revenue of recycled materials. A numerical example is used to evaluate the proposed model. Results show that fulfillment of Green Product Development not only can reduce the environmental impact of products but also it will increase profit of company in long term.

Keywords: green product, design for environment, C-V-P model, trade-off analysis

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12159 Decision-Making using Fuzzy Linguistic Hypersoft Set Topology

Authors: Muhammad Saqlain, Poom Kumam

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Language being an abstract system and creative act, is quite complicated as its meaning varies depending on the context. The context is determined by the empirical knowledge of a person, which is derived from observation and experience. About further subdivided attributes, the decision-making challenges may entail quantitative and qualitative factors. However, because there is no norm for putting a numerical value on language, existing approaches cannot carry out the operations of linguistic knowledge. The assigning of mathematical values (fuzzy, intuitionistic, and neutrosophic) to any decision-making problem; without considering any rule of linguistic knowledge is ambiguous and inaccurate. Thus, this paper aims to provide a generic model for these issues. This paper provides the linguistic set structure of the fuzzy hypersoft set (FLHSS) to solve decision-making issues. We have proposed the definition some basic operations like AND, NOT, OR, AND, compliment, negation, etc., along with Topology and examples, and properties. Secondly, the operational laws for the fuzzy linguistic hypersoft set have been proposed to deal with the decision-making issues. Implementing proposed aggregate operators and operational laws can be used to convert linguistic quantifiers into numerical values. This will increase the accuracy and precision of the fuzzy hypersoft set structure to deal with decision-making issues.

Keywords: linguistic quantifiers, aggregate operators, multi-criteria decision making (mcdm)., fuzzy topology

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12158 Data Structure Learning Platform to Aid in Higher Education IT Courses (DSLEP)

Authors: Estevan B. Costa, Armando M. Toda, Marcell A. A. Mesquita, Jacques D. Brancher

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The advances in technology in the last five years allowed an improvement in the educational area, as the increasing in the development of educational software. One of the techniques that emerged in this lapse is called Gamification, which is the utilization of video game mechanics outside its bounds. Recent studies involving this technique provided positive results in the application of these concepts in many areas as marketing, health and education. In the last area there are studies that cover from elementary to higher education, with many variations to adequate to the educators methodologies. Among higher education, focusing on IT courses, data structures are an important subject taught in many of these courses, as they are base for many systems. Based on the exposed this paper exposes the development of an interactive web learning environment, called DSLEP (Data Structure Learning Platform), to aid students in higher education IT courses. The system includes basic concepts seen on this subject such as stacks, queues, lists, arrays, trees and was implemented to ease the insertion of new structures. It was also implemented with gamification concepts, such as points, levels, and leader boards, to engage students in the search for knowledge and stimulate self-learning.

Keywords: gamification, Interactive learning environment, data structures, e-learning

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12157 Comparative Study in Evaluating the Antioxidation Efficiency for Native Types Antioxidants Extracted from Crude Oil with the Synthesized Class

Authors: Mohammad Jamil Abd AlGhani

Abstract:

The natural native antioxidants N,N-P-methyl phenyl acetone and N,N-phenyl acetone were isolated from the Iraqi crude oil region of Kirkuk by ion exchange and their structure was characterized by spectral and chemical analysis methods. Tetraline was used as a liquid hydrocarbon to detect the efficiency of isolated molecules at elevated temperature (393 K) that it has physicochemical specifications and structure closed to hydrocarbons fractionated from crude oil. The synthesized universal antioxidant 2,6-ditertiaryisobutyl-p-methyl phenol (Unol) with known stochiometric coefficient of inhibition equal to (2) was used as a model for comparative evaluation at the same conditions. Modified chemiluminescence method was used to find the amount of absorbed oxygen and the induction periods in and without the existence of isolated antioxidants molecules. The results of induction periods and quantity of absorbed oxygen during the oxidation process were measured by manometric installation. It was seen that at specific equal concentrations of N,N-phenyl acetone and N, N-P-methyl phenyl acetone in comparison with Unol at 393 K were with (2) and (2.5) times efficient than do Unol. It means that they had the ability to inhibit the formation of new free radicals and prevent the chain reaction to pass from the propagation to the termination step rather than decomposition of formed hydroperoxides.

Keywords: antioxidants, chemiluminescence, inhibition, Unol

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12156 A Development of Portable Intrinsically Safe Explosion-Proof Type of Dual Gas Detector

Authors: Sangguk Ahn, Youngyu Kim, Jaheon Gu, Gyoutae Park

Abstract:

In this paper, we developed a dual gas leak instrument to detect Hydrocarbon (HC) and Monoxide (CO) gases. To two kinds of gases, it is necessary to design compact structure for sensors. And then it is important to draw sensing circuits such as measuring, amplifying and filtering. After that, it should be well programmed with robust, systematic and module coding methods. In center of them, improvement of accuracy and initial response time are a matter of vital importance. To manufacture distinguished gas leak detector, we applied intrinsically safe explosion-proof structure to lithium ion battery, main circuits, a pump with motor, color LCD interfaces and sensing circuits. On software, to enhance measuring accuracy we used numerical analysis such as Lagrange and Neville interpolation. Performance test result is conducted by using standard Methane with seven different concentrations with three other products. We want raise risk prevention and efficiency of gas safe management through distributing to the field of gas safety. Acknowledgment: This study was supported by Small and Medium Business Administration under the research theme of ‘Commercialized Development of a portable intrinsically safe explosion-proof type dual gas leak detector’, (task number S2456036).

Keywords: gas leak, dual gas detector, intrinsically safe, explosion proof

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12155 Characterization of Lahar Sands for Reclamation Projects in the Manila Bay, Philippines

Authors: Julian Sandoval, Philipp Schober

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Lahar sand (lahars) is a material that originates from volcanic debris flows. During and after a volcano eruption, the lahars can move at speeds up to 22 meters per hour or more, so they can easily cover extensive areas and destroy any structure in their path. Mount Pinatubo eruption (1991) brought lahars to its vicinities, and its use has been a matter of research ever since. Lahars are often disposed of for land reclamation projects in the Manila Bay, Philippines. After reclamation, some deep loss deposits may still present and they are prone to liquefaction. To mitigate the risk of liquefaction of such deposits, Vibro compaction has been proposed and used as a ground improvement technique. Cone penetration testing (CPT) campaigns are usually initiated to monitor the effectiveness of the ground improvement works by vibro compaction. The CPT cone resistance is used to analyses the in-situ relative density of the reclaimed sand before and after compaction. Available correlations between the CPT cone resistance and the relative density are only valid for non-crushable sands. Due to the partially crushable nature of lahars, the CPT data requires to be adjusted to allow for a correct interpretation of the CPT data. The objective of this paper is to characterize the chemical and mechanical properties of the lahar sands used for an ongoing project in the Port of Manila, which comprises reclamation activities using lahars from the east of Mount Pinatubo, it investigates their effect in the proposed correction factor. Additionally, numerous CPTs were carried out in a test trial and during the execution of the project. Based on this data, the influence of the grid spacing, compaction steps and the holding time on the compaction results are analyzed. Moreover, the so-called “aging effect” of the lahars is studied by comparing the results of the CPT testing campaign at different times after the vibro compaction activities. A considerable increase in the tip resistance of the CPT was observed over time.

Keywords: vibro compaction, CPT, lahar sands, correction factor, chemical composition

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12154 Federalism, a System of Government: Comparative Study of Australia and Canada

Authors: Rana Tajammal Rashid

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Federalism is a political system in which government power and responsibility are divided between a federal legislature and units of the state or provincial legislatures. This system provides the structure for the states having large territory and through that can manage the state affairs and administration easily. Many of the largest countries in the world are federations, like; The United States, Canada, India, Pakistan South Africa, Argentina, and Australia. Every large democratic nation has a federal system of government. This study will explore the feature and good governance of two developed countries Canada and Australia. This study will be helpful to the developing countries like Pakistan, India which have a federal form of structure to run the affairs of the state. In the federal system of Pakistan there are lot of issues and conflicts with the provinces with a comparative study of these two developed countries, i.e., Australia and Canada, our policy and decision maker political actors will understand in which way a state will successfully manage the issues related to federalism. This study will also provide the help to the students of comparative politics that how to analysis the different political system of the developed countries of the world.

Keywords: federalism, features of federalism, types of federalism, history of federalism, Australian federalism, Canadian federalism, federalism developments, executives, federal and provincial autonomy legislative, judicial

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12153 Developing a Modular Architecture of Apparel Product

Authors: Yu Zhao, Mengqin Sun, Yahui Zhang

Abstract:

Apparel products (or apparel) with the sense of aesthetics, usability (ergonomics) and function are fundamental and varied in people’s daily life. The numerous apparel thus produced by apparel industry, have been triggered many issues, such as the waste of sources and the environmental pollutions. In this study, a hybrid architecture called modular architecture of apparel (MAA) has been proposed to deal with the variety of apparel, and thus to overcome the aforementioned issues. Generally, the establishment of MAA takes advantage of the modular design of a general product that a product is assembled with many modules through their modular interface connector. The development of MAA is to first analyze the structure of apparel in terms of the necessity to form an apparel and the aesthetics, ergonomics, and function of apparel; then to divide apparel into many segments (or module in product design) based on the structure of apparel; to develop modular interfaces and modular interface connectors in terms of the features of apparel’s modules. It is noted that in the general product design, modules of a product are only about the function and ergonomics, but in MAA, the module of aesthetics is developed. Further, an apparel design with employing the MAA is carried out to validate its usefulness and efficiency. There are three contributions out of this study, the first is to overcome the aforementioned issues (i.e. waste of source and environmental pollutions); the second is the improvement of the modular design for product by considering aesthetics; the third is to add the value in realizing the personalized mass production of apparel in the near future.

Keywords: apparel, architecture, modular design, segment

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12152 Numerical Analysis and Influence of the Parameters on Slope Stability

Authors: Fahim Kahlouche, Alaoua Bouaicha, Sihem Chaîbeddra, Sid-Ali Rafa, Abdelhamid Benouali

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A designing of a structure requires its realization on rough or sloping ground. Besides the problem of the stability of the landslide, the behavior of the foundations that are bearing the structure is influenced by the destabilizing effect of the ground’s slope. This article focuses on the analysis of the slope stability exposed to loading by introducing the different factors influencing the slope’s behavior on the one hand, and on the influence of this slope on the foundation’s behavior on the other hand. This study is about the elastoplastic modelization using FLAC 2D. This software is based on the finite difference method, which is one of the older methods of numeric resolution of differential equations system with initial and boundary conditions. It was developed for the geotechnical simulation calculation. The aim of this simulation is to demonstrate the notable effect of shear modulus « G », cohesion « C », inclination angle (edge) « β », and distance between the foundation and the head of the slope on the stability of the slope as well as the stability of the foundation. In our simulation, the slope is constituted by homogenous ground. The foundation is considered as rigid/hard; therefore, the loading is made by the application of the vertical strengths on the nodes which represent the contact between the foundation and the ground. 

Keywords: slope, shallow foundation, numeric method, FLAC 2D

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12151 Assessing the Effect of Freezing and Thawing of Coverzone of Ground Granulated Blast-Furnace Slag Concrete

Authors: Abdulkarim Mohammed Iliyasu, Mahmud Abba Tahir

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Freezing and thawing are considered to be one of the major causes of concrete deterioration in the cold regions. This study aimed at assessing the freezing and thawing of concrete within the cover zone by monitoring the formation of ice and melting at different temperatures using electrical measurement technique. A multi-electrode array system was used to obtain the resistivity of ice formation and melting at discrete depths within the cover zone of the concrete. A total number of four concrete specimens (250 mm x 250 mm x 150 mm) made of ordinary Portland cement concrete and ordinary Portland cement replaced by 65% ground granulated blast furnace slag (GGBS) is investigated. Water/binder ratios of 0.35 and 0.65 were produced and ponded with water to ensure full saturation and then subjected to freezing and thawing process in a refrigerator within a temperature range of -30 0C and 20 0C over a period of time 24 hours. The data were collected and analysed. The obtained results show that the addition of GGBS changed the pore structure of the concrete which resulted in the decrease in conductance. It was recommended among others that, the surface of the concrete structure should be protected as this will help to prevent the instantaneous propagation of ice trough the rebar and to avoid corrosion and subsequent damage.

Keywords: concrete, conductance, deterioration, freezing and thawing

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12150 On Influence of Web Openings Presence on Structural Performance of Steel and Concrete Beams

Authors: Jakub Bartus, Jaroslav Odrobinak

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In general, composite steel and concrete structures present an effective structural solution utilizing the full potential of both materials. As they have numerous advantages on the construction side, they can greatly reduce the overall cost of construction, which has been the main objective of the last decade, highlighted by the current economic and social crisis. The study represents not only an analysis of composite beams’ behavior having web openings but emphasizes the influence of these openings on the total strain distribution at the level of the steel bottom flange as well. The major investigation was focused on a change in structural performance with respect to various layouts of openings. Examining this structural modification, an improvement of load carrying capacity of composite beams was a prime objective. The study is divided into analytical and numerical parts. The analytical part served as an initial step into the design process of composite beam samples, in which optimal dimensions and specific levels of utilization in individual stress states were taken into account. The numerical part covered the discretization of the preset structural issue in the form of a finite element (FE) model using beam and shell elements accounting for material non–linearities. As an outcome, several conclusions were drawn describing and explaining the effect of web opening presence on the structural performance of composite beams.

Keywords: beam, steel flange, total strain, web opening

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12149 Structural Health Monitoring of Buildings–Recorded Data and Wave Method

Authors: Tzong-Ying Hao, Mohammad T. Rahmani

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This article presents the structural health monitoring (SHM) method based on changes in wave traveling times (wave method) within a layered 1-D shear beam model of structure. The wave method measures the velocity of shear wave propagating in a building from the impulse response functions (IRF) obtained from recorded data at different locations inside the building. If structural damage occurs in a structure, the velocity of wave propagation through it changes. The wave method analysis is performed on the responses of Torre Central building, a 9-story shear wall structure located in Santiago, Chile. Because events of different intensity (ambient vibrations, weak and strong earthquake motions) have been recorded at this building, therefore it can serve as a full-scale benchmark to validate the structural health monitoring method utilized. The analysis of inter-story drifts and the Fourier spectra for the EW and NS motions during 2010 Chile earthquake are presented. The results for the NS motions suggest the coupling of translation and torsion responses. The system frequencies (estimated from the relative displacement response of the 8th-floor with respect to the basement from recorded data) were detected initially decreasing approximately 24% in the EW motion. Near the end of shaking, an increase of about 17% was detected. These analysis and results serve as baseline indicators of the occurrence of structural damage. The detected changes in wave velocities of the shear beam model are consistent with the observed damage. However, the 1-D shear beam model is not sufficient to simulate the coupling of translation and torsion responses in the NS motion. The wave method is proven for actual implementation in structural health monitoring systems based on carefully assessing the resolution and accuracy of the model for its effectiveness on post-earthquake damage detection in buildings.

Keywords: Chile earthquake, damage detection, earthquake response, impulse response function, shear beam model, shear wave velocity, structural health monitoring, torre central building, wave method

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12148 The Numerical and Experimental Analysis of Compressed Composite Plate in Asymmetrical Arrangement of Layers

Authors: Katarzyna Falkowicz

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The work focused on the original concept of a thin-walled plate element with a cut-out, for use as a spring or load-bearing element. The subject of the study were rectangular plates with a cut-out with variable geometrical parameters and with a variable angle of fiber arrangement, made of a carbon-epoxy composite with high strength properties in an asymmetrical arrangement, subjected to uniform compression. The influence of geometrical parameters of the cut-out and the angle of fiber arrangement on the value of critical load of the structure and buckling form was investigated. Uniform thin plates are relatively cheap to manufacture, however due to their low bending stiffness; they can carry relatively small loads. The lowest form of loss of plate stability, which is the bending form, leads to its rapid destruction due to high deflection increases, with a slight increase in compressive load - low rigidity of the structure. However, the stiffness characteristics of the structure change significantly when the work of plate is forcing according to the higher flexural-torsional form of buckling. The plate is able to carry a much higher compressive load while maintaining much stiffer work characteristics in the post-critical range. The calculations carried out earlier show that plates with forced higher form of buckling are characterized by stable, progressive paths of post-critical equilibrium, enabling their use as elastic elements. The characteristics of such elements can be designed in a wide range by changing the geometrical parameters of the cut-out, i.e. height and width as well as by changing the angle of fiber arrangement The commercial ABAQUS program using the finite element method was used to develop the discrete model and perform numerical calculations. The obtained results are of significant practical importance in the design of structures with elastic elements, allowing to achieve the required maintenance characteristics of the device.

Keywords: buckling mode, numerical method, unsymmetrical laminates, thin-walled elastic elements

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12147 Comprehensive Critical Review for Static and Dynamic Soil-Structure Interaction Between Winkler, Pasternak and Three-Dimensional Method of Buried Pipelines

Authors: N. E.Sam, S. R.Singh

Abstract:

Pipeline infrastructure are a valuable asset to the country that help in transporting fluid and gas from one place to another and contribute in keeping the country functioning both physically and economically. During seismic activity, additional loads are acted on the buried pipelines becoming a salient parameter to be studied in soil pipe interaction. Winkler Beam Theory is a commonly used approach for design of underground buried structures however this theory does not take into account shear and dynamic loading parameters in consideration. Shear can be addressed in Pasternak Theory – an improved model of Winkler Theory. However dynamic loading condition and horizontal displacement is not considered in either method. A comprehensive critical review between Winkler Beam Method, Pasternak Method and Three-Dimensional Method in finite element analysis is to be done in this paper for seismic forces. Study of the influence of depth and displacement of soil in correspondence to stiffness value and influence of horizontal displacement for design of underground structures is considered.

Keywords: finite element, pasternak theory, seismic, soil-structure interaction, three-dimensional theory, winkler theory

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12146 Optimal Sliding Mode Controller for Knee Flexion during Walking

Authors: Gabriel Sitler, Yousef Sardahi, Asad Salem

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This paper presents an optimal and robust sliding mode controller (SMC) to regulate the position of the knee joint angle for patients suffering from knee injuries. The controller imitates the role of active orthoses that produce the joint torques required to overcome gravity and loading forces and regain natural human movements. To this end, a mathematical model of the shank, the lower part of the leg, is derived first and then used for the control system design and computer simulations. The design of the controller is carried out in optimal and multi-objective settings. Four objectives are considered: minimization of the control effort and tracking error; and maximization of the control signal smoothness and closed-loop system’s speed of response. Optimal solutions in terms of the Pareto set and its image, the Pareto front, are obtained. The results show that there are trade-offs among the design objectives and many optimal solutions from which the decision-maker can choose to implement. Also, computer simulations conducted at different points from the Pareto set and assuming knee squat movement demonstrate competing relationships among the design goals. In addition, the proposed control algorithm shows robustness in tracking a standard gait signal when accounting for uncertainty in the shank’s parameters.

Keywords: optimal control, multi-objective optimization, sliding mode control, wearable knee exoskeletons

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12145 Comparison of Reserve Strength Ratio and Capacity Curve Parameters of Offshore Platforms with Distinct Bracing Arrangements

Authors: Aran Dezhban, Hooshang Dolatshahi Pirooz

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The phenomenon of corrosion, especially in the Persian Gulf region, is the main cause of the deterioration of offshore platforms, due to the high corrosion of its water. This phenomenon occurs mostly in the area of water spraying, threatening the members of the first floor of the jacket, legs, and piles in this area. In the current study, the effect of bracing arrangement on the Capacity Curve and Reserve Strength Ratio of Fixed-Type Offshore Platforms is investigated. In order to continue the operation of the platform, two modes of robust and damaged structures are considered, while checking the adequacy of the platform capacity based on the allowable values of API RP-2SIM regulations. The platform in question is located in the Persian Gulf, which is modeled on the OpenSEES software. In this research, the Nonlinear Pushover Analysis has been used. After validation, the Capacity Curve of the studied platforms is obtained and then their Reserve Strength Ratio is calculated. Results are compared with the criteria in the API-2SIM regulations.

Keywords: fixed-type jacket structure, structural integrity management, nonlinear pushover analysis, robust and damaged structure, reserve strength ration, capacity curve

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12144 Mesovarial Morphological Changes in Offspring Exposed to Maternal Cold Stress

Authors: Ariunaa.S., Javzandulam E., Chimegsaikhan S., Altantsetseg B., Oyungerel S., Bat-Erdene T., Naranbaatar S., Otgonbayar B., Suvdaa N., Tumenbayar B.

Abstract:

Introduction: Prenatal stress has been linked to heightened allergy sensitivity in offspring. However, there is a notable absence of research on the mesovarium structure of offspring born from mothers subjected to cold stress during pregnancy. Understanding the impact of maternal cold stress on the mesovarium structure could provide valuable insights into reproductive health outcomes in offspring. Objective: This study aims to investigate structural changes in the mesovarium of offspring born from cold-stress affected rats. Material and Methods: 20 female Westar rats weighing around 200g were chosen and evenly divided into four containers; then, 2-3 male rats were introduced to each container. The Papanicolaou method was used to estimate the spermatozoa and estrus period from vaginal swabs taken from female rats at 8:00 a.m. Female rats examined with the presence of spermatozoa during the estrous phase of the estrous cycle are defined as pregnant. Pregnant rats are divided into experimental and control groups. The experimental group was stressed using the model of severe and chronic cold stress for 30 days. They were exposed to cold stress for 3 hours each morning between 8:00 and 11:00 o’clock at a temperature of minus 15 degrees Celsius. The control group was kept under normal laboratory conditions. Newborn female rats from both experimental and control groups were selected. At 2 months of age, rats were euthanized by decapitation, and their mesovaria were collected. Tissues were fixed in 4% formalin, embedded in paraffin, and sectioned into 5μm thick slices. The sections were stained with H&E and digitized by digital microscope. The area of brown fat and inflammatory infiltrations were quantified using Image J software. The blood cortisol levels were measured using ELISA. Data are expressed as the mean ± standard error of the mean (SEM). The Mann-Whitney test was used to compare the two groups. All analyses were performed using Prism (GraphPad Software). A p-value of < 0.05 was considered statistically significant. Result: Offspring born from stressed mothers exhibited significant physiological differences compared to the control group. Specifically, the body weight of offspring from stressed mothers was significantly lower than the control group (p=0.0002). Conversely, the cortisol level in offspring from stressed mothers was significantly higher (p=0.0446). Offspring born from stressed mothers showed a statistically significant increase in brown fat area compared to the control group (p=0.01). Additionally, offspring from stressed mothers had a significantly higher number of inflammatory infiltrates in their mesovarium compared to the control group (p<0.047). These results indicate the profound impact of maternal stress on offspring physiology, affecting body weight, stress hormone levels, metabolic characteristics, and inflammatory responses. Conclusion: Exposure to cold stress during pregnancy has significant repercussions on offspring physiology. Our findings demonstrate that cold stress exposure leads to increased blood cortisol levels, brown fat accumulation, and inflammatory cell infiltration in offspring. These results underscore the profound impact of maternal stress on offspring health and highlight the importance of mitigating environmental stressors during pregnancy to promote optimal offspring outcomes.

Keywords: brown fat, cold stress during pregnancy, inflammation, mesovarium

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12143 Development and Verification of the Idom Shielding Optimization Tool

Authors: Omar Bouhassoun, Cristian Garrido, César Hueso

Abstract:

The radiation shielding design is an optimization problem with multiple -constrained- objective functions (radiation dose, weight, price, etc.) that depend on several parameters (material, thickness, position, etc.). The classical approach for shielding design consists of a brute force trial-and-error process subject to previous designer experience. Therefore, the result is an empirical solution but not optimal, which can degrade the overall performance of the shielding. In order to automate the shielding design procedure, the IDOM Shielding Optimization Tool (ISOT) has been developed. This software combines optimization algorithms with the capabilities to read/write input files, run calculations, as well as parse output files for different radiation transport codes. In the first stage, the software was established to adjust the input files for two well-known Monte Carlo codes (MCNP and Serpent) and optimize the result (weight, volume, price, dose rate) using multi-objective genetic algorithms. Nevertheless, its modular implementation easily allows the inclusion of more radiation transport codes and optimization algorithms. The work related to the development of ISOT and its verification on a simple 3D multi-layer shielding problem using both MCNP and Serpent will be presented. ISOT looks very promising for achieving an optimal solution to complex shielding problems.

Keywords: optimization, shielding, nuclear, genetic algorithm

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12142 Liquefaction Potential Assessment Using Screw Driving Testing and Microtremor Data: A Case Study in the Philippines

Authors: Arturo Daag

Abstract:

The Philippine Institute of Volcanology and Seismology (PHIVOLCS) is enhancing its liquefaction hazard map towards a detailed probabilistic approach using SDS and geophysical data. Target sites for liquefaction assessment are public schools in Metro Manila. Since target sites are in highly urbanized-setting, the objective of the project is to conduct both non-destructive geotechnical studies using Screw Driving Testing (SDFS) combined with geophysical data such as refraction microtremor array (ReMi), 3 component microtremor Horizontal to Vertical Spectral Ratio (HVSR), and ground penetrating RADAR (GPR). Initial test data was conducted in liquefaction impacted areas from the Mw 6.1 earthquake in Central Luzon last April 22, 2019 Province of Pampanga. Numerous accounts of liquefaction events were documented areas underlain by quaternary alluvium and mostly covered by recent lahar deposits. SDS estimated values showed a good correlation to actual SPT values obtained from available borehole data. Thus, confirming that SDS can be an alternative tool for liquefaction assessment and more efficient in terms of cost and time compared to SPT and CPT. Conducting borehole may limit its access in highly urbanized areas. In order to extend or extrapolate the SPT borehole data, non-destructive geophysical equipment was used. A 3-component microtremor obtains a subsurface velocity model in 1-D seismic shear wave velocity of the upper 30 meters of the profile (Vs30). For the ReMi, 12 geophone array with 6 to 8-meter spacing surveys were conducted. Microtremor data were computed through the Factor of Safety, which is the quotient of Cyclic Resistance Ratio (CRR) and Cyclic Stress Ratio (CSR). Complementary GPR was used to study the subsurface structure and used to inferred subsurface structures and groundwater conditions.

Keywords: screw drive testing, microtremor, ground penetrating RADAR, liquefaction

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12141 Analysis and Design of Offshore Met Mast Supported on Jacket Substructure

Authors: Manu Manu, Pardha J. Saradhi, Ramana M. V. Murthy

Abstract:

Wind Energy is accepted as one of the most developed, cost effective and proven renewable energy technologies to meet increasing electricity demands in a sustainable manner. Preliminary assessment studies along Indian Coastline by Ministry of New and Renewable Energy have indicated prospects for development of offshore wind power along Tamil Nadu Coast, India. The commercial viability of a wind project mainly depends on wind characteristics on site. Hence, it is internationally recommended to perform site-specific wind resource assessment based on two years’ wind profile as a part of the feasibility study. Conventionally, guy wire met mast are used onshore for the collection of wind profile. Installation of similar structure in offshore requires complex marine spread and are very expensive. In the present study, an attempt is made to develop 120 m long lattice tower supported on the jacket, piled to the seabed at Rameshwaram, Tamil Nadu, India. Offshore met-masts are subjected to combined wind and hydrodynamic loads, and these lateral loads should be safely transferred to soil. The wind loads are estimated based on gust factor method, and the hydrodynamic loads are estimated by Morison’s equation along with suitable wave theory. The soil is modeled as three nonlinear orthogonal springs based on API standards. The structure configuration and optimum member sizes are obtained for extreme cyclone events. The dynamic behavior of mast under coupled wind and wave loads is also studied. The static responses of a mast with jacket type offshore platform have been studied using a frame model in SESAM. It is found from the study that the maximum displacement at the top of the mast for the random wave is 0.003 m and that of the tower for wind is 0.08 m during the steady state. The dynamic analysis results indicate that the structure is safe against coupled wind and wave loading.

Keywords: offshore wind, mast, static, aerodynamic load, hydrodynamic load

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12140 Modeling Anisotropic Damage Algorithms of Metallic Structures

Authors: Bahar Ayhan

Abstract:

The present paper is concerned with the numerical modeling of the inelastic behavior of the anisotropically damaged ductile materials, which are based on a generalized macroscopic theory within the framework of continuum damage mechanics. Kinematic decomposition of the strain rates into elastic, plastic and damage parts is basis for accomplishing the structure of continuum theory. The evolution of the damage strain rate tensor is detailed with the consideration of anisotropic effects. Helmholtz free energy functions are constructed separately for the elastic and inelastic behaviors in order to be able to address the plastic and damage process. Additionally, the constitutive structure, which is based on the standard dissipative material approach, is elaborated with stress tensor, a yield criterion for plasticity and a fracture criterion for damage besides the potential functions of each inelastic phenomenon. The finite element method is used to approximate the linearized variational problem. Stress and strain outcomes are solved by using the numerical integration algorithm based on operator split methodology with a plastic and damage (multiplicator) variable separately. Numerical simulations are proposed in order to demonstrate the efficiency of the formulation by comparing the examples in the literature.

Keywords: anisotropic damage, finite element method, plasticity, coupling

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12139 Research on the Calculation Method of Smartization Rate of Concrete Structure Building Construction

Authors: Hongyu Ye, Hong Zhang, Minjie Sun, Hongfang Xu

Abstract:

In the context of China's promotion of smart construction and building industrialization, there is a need for evaluation standards for the development of building industrialization based on assembly-type construction. However, the evaluation of smart construction remains a challenge in the industry's development process. This paper addresses this issue by proposing a calculation and evaluation method for the smartization rate of concrete structure building construction. The study focuses on examining the factors of smart equipment application and their impact on costs throughout the process of smart construction design, production, transfer, and construction. Based on this analysis, the paper presents an evaluation method for the smartization rate based on components. Furthermore, it introduces calculation methods for assessing the smartization rate of buildings. The paper also suggests a rapid calculation method for determining the smartization rate using Building Information Modeling (BIM) and information expression technology. The proposed research provides a foundation for the swift calculation of the smartization rate based on BIM and information technology. Ultimately, it aims to promote the development of smart construction and the construction of high-quality buildings in China.

Keywords: building industrialization, high quality building, smart construction, smartization rate, component

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12138 Genre Analysis of Postgraduate Theses and Dissertations: Case of Statement of the Problem

Authors: H. Mashhady, H. A. Manzoori, M. Doosti, M. Fatollahi

Abstract:

This study reports a descriptive research in the form of a genre analysis of postgraduates' theses and dissertations at three Iranian universities, including Ferdowsi, Tehran, and Tarbiat Moddares universities. The researchers sought to depict the generic structure of “statement of the problem” section of PhD dissertations and MA theses. Moreover, researchers desired to find any probable variety based on the year the dissertations belonged, to see weather genre-consciousness developed among Iranian postgraduates. To obtain data, “statement of the problem” section of 90 Ph.D. dissertations and MA theses from 2001 to 2013 in Teaching English as a Foreign Language (TEFL) at above-mentioned universities was selected. Frequency counts was employed for the quantitative method of data analysis, while genre analysis was used as the qualitative method. Inter-rater reliability was found to be about 0.93. Results revealed that students in different degrees at each of these universities used various generic structures for writing “statement of the problem”. Moreover, comparison of different time periods (2001-2006, and 2007-2013) revealed that postgraduates in the second time period, regardless of their degree and university, employed more similar generic structures which can be optimistically attributed to a general raise in genre awareness.

Keywords: genre, genre analysis, Ph.D. and MA dissertations, statement of the problem, generic structure

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12137 Vine Copula Structure among Yield, Price and Weather Variables for Rating Crop Insurance Premium

Authors: Jiemiao Chen, Shuoxun Xu

Abstract:

The main goal of our research is to apply the Vine copula measuring dependency between price, temperature, and precipitation indices to calculate a fair crop insurance premium. This research is focused on Worth, Iowa, United States, over the period from 2000 to 2020, where the farmers are dependent on precipitation and average temperature during the growth period of corn. Our proposed insurance considers both the natural risk and the price risk in agricultural production. We first estimate the distributions of crops using parametric methods based on Goodness of Fit tests, and then Vine Copula is applied to model dependence between yield price, crop yield, and weather indices. Once the vine structure and its parameters are determined based on AIC/BIC criteria and forecasting price and yield are obtained from the ARIMA model, we calculate this crop insurance premium using the simulation data generated from the vine copula by the Monte Carlo Simulation method. It is shown that, compared with traditional crop insurance, our proposed insurance is more fair and thus less costly for the farmers and government.

Keywords: vine copula, weather index, crop insurance premium, insurance risk management, Monte Carlo simulation

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12136 In-situ Fabrication of a Metal-Intermetallic Composite: Microstructure Evolution and Mechanical Response

Authors: Monireh Azimi, Mohammad Reza Toroghinejad, Leo A. I. Kestens

Abstract:

The role of different metallic and intermetallic reinforcements on the microstructure and the associated mechanical response of a composite is of crucial importance. To investigate this issue, a multiphase metal-intermetallic composite was in-situ fabricated through reactive annealing and accumulative roll bonding (ARB) processes. EBSD results indicated that the lamellar grain structure of the Al matrix after the first cycle has evolved with increasing strain to a mixed structure consisting of equiaxed and lamellar grains, whereby the steady-state did not occur after the 3rd (last) cycle—applying a strain of 6.1 in the Al phase, the length and thickness of the grains reduced by 92.2% and 97.3%, respectively, compared to the annealed state. Intermetallic phases together with the metallic reinforcement of Ni influence grain fragmentation of the Al matrix and give rise to a specific texture evolution by creating heterogeneity in the strain and flow patterns. Mechanical properties of the multiphase composite demonstrated the yield and ultimate tensile strengths of 217.9 MPa and 340.1 MPa, respectively, compared to 48.7 MPa and 55.4 MPa in the metal-intermetallic laminated (MIL) sandwich before applying the ARB process, which corresponds to an increase of 347% and 514% of yield and tensile strength, respectively.

Keywords: accumulative roll bonding, mechanical properties, metal-intermetallic composite, severe plastic deformation, texture

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12135 Digital Design and Fabrication: A Review of Trend and Its Impact in the African Context

Authors: Mohamed Al Araby, Amany Salman, Mostafa Amin, Mohamed Madbully, Dalia Keraa, Mariam Ali, Marah Abdelfatah, Mariam Ahmed, Ahmed Hassab

Abstract:

In recent years, the architecture, engineering, and construction (A.E.C.) industry have been exposed to important innovations, most notably the global integration of digital design and fabrication (D.D.F.) processes in the industry’s workflow. Despite this evolution in that sector, Africa was excluded from the examination of this development. The reason behind this exclusion is the preconceived view of it as a developing region that still employs traditional methods of construction. The primary objective of this review is to investigate the trend of digital construction (D.C.) in the African environment and the difficulties in its regular utilization of it. This objective can be attained by recognizing the notion of distributed computing in Africa and evaluating the impact of the projects deploying this technology on both the immediate and broader contexts. The paper’s methodology begins with the collection of data from 224 initiatives throughout Africa. Then, 50 of these projects were selected based on the criteria of the project's recency, typology variety, and location diversity. After that, a literature-based comparative analysis was undertaken. This study’s findings reveal a pattern of motivation for applying digital fabrication processes. Moreover, it is essential to evaluate the socio-economic effects of these projects on the population living near the analyzed subject. The last step in this study is identifying the influence on the neighboring nations.

Keywords: Africa, digital construction, digital design, fabrication

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12134 Hardness and Microstructure of Rapidly Quenched Aluminum Alloys

Authors: Mehdi Ghatus

Abstract:

Two simple apparatus based on the hammer and anvil principle have been constructed and used to study the microstructure and micro-hardness characteristics of some AL-base alloys. Foils with thicknesses arranging from 20 µm up to 600 µm have been obtained. The cooling rate was estimated to be in the range 10^4 - 10^5 K/sec. Microstructure study of rapidly quenched Al-30% Si foils indicated that with decreasing the foil thickness the size of primary Si crystallites decreases in the whole investigated range (0.64-0.15 mm). However, the volume fraction of the primary Si crystals in the structure remained constant down to thickness the primary Si volume fraction started to decrease. Rapid quenching of Al- 14-16% Cu showed single phase cell structure. In foils up to 0.55 mm with decreasing the foil thickness the cell size decreases and micro-hardness increases particularly in foils below 0.3 mm in thickness. Isochronal annealing of theses foils show that the highly supersaturated Al-14-16% Cu solid solution decomposes readily at relatively low temperature and short time intervals. The maximum hardness is obtained after annealing at 100 °C for 30 minutes. However with decreasing the Cu content of the foils the precipitation process is largely delayed. Eight hours of annealing at 100 °C was not enough to achieve the maximum hardness in Al-4% Cu thin foils. The achieved hardness value was more than twice of the maximum hardness obtained in articles of similar composition but conventionally aged.

Keywords: aluminum, hardness, alloys, quenched aluminum

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12133 Tradition and Modernity in Translation Studies: The Case of Undergraduate and Graduate Programs at Unicamp, Brazil

Authors: Erica Lima

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In Brazil, considering the (little) age of translation studies, it can be argued that the University of Campinas is traditionally an important place for graduate studies in translation. The story is told from the accreditation for the Masters, in 1987, and the Doctoral program, in 1993, within the Graduate Program in Applied Linguistics. Since the beginning, the program boasted cutting-edge research, with theoretical reflections on various aspects, and with different methodological trends. However, on the one hand, the graduate studies development was continuously growing, but on the other, it is not what was observed in the undergraduate degree program. Currently, there are only a few disciplines of Translation Theory and Practice, which does not seem to respond to student aspirations. The objective of this paper is to present the characteristics of the university’s graduate program as something profitable, considering the concern in relating the research to the historical moment in which we are living, with research conducted in a socially compromised environment and committed to the impact that it will cause ethically and socially, as well as to question the undergraduate program paths. The objective is also to discuss and propose changes, considering the limited scope currently achieved. In light of the information age, in which we have an avalanche of information, we believe that the training of translators in the undergraduate degree should be reviewed, with the goal of retracing current paths and following others that are consistent with our historical period, marked by virtual and real, by the shuffling of borders and languages, the need for new language policies, greater inclusion, and more acceptance of others. We conclude that we need new proposals for the development of the translator in an undergraduate program, and also present suggestions to be implemented in the graduate program.

Keywords: graduate Brazilian program, undergraduate Brazilian program, translator’s education, Unicamp

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12132 Nitrogen Doping Effect on Enhancement of Electrochemical Performance of a Carbon Nanotube Based Microsupercapacitor

Authors: Behnoush Dousti, Ye Choi, Gil S. Lee

Abstract:

Microsupercapacitors (MScs) are known as the future of miniaturized energy sources that can be coupled to a battery to deliver stable and constant energy to microelectronics. Among all their counterparts, electrochemical microsupercapacitor have drawn the most research attention due to their higher power density and long cycle life. Designing the microstructure and choosing the electroactive materials are two significant factors that greatly affect the performance of the device. Here, we report successful fabrication and characterization of a microsupercapacitor with interdigitated structure based on Carbon nanotube sheets (CNT sheet). Novel structure of highly aligned CNT sheet as the electrode materials which also offers excellent conductivity and large surface area along with doping with nitrogen, enabled us to develop a device with serval order of magnitude higher electrochemical performance than the pristine CNT in aqueous electrolyte including high specific capacitance and rate capabilities and excellent cycle life over 10000 cycles. Geometric parameters such as finger width and gap size were also studied and it was shown the device performance is much depended on them. Results of this study confirms the potential of CNT sheet for future energy storage devices.

Keywords: carbon nanotube, energy storage systems, microsupercapacitor, nitrogen doping

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12131 Research on the Dynamic Characteristics of Multi-Condition Penetration of Concrete by Warhead-Fuze Systems

Authors: Shaoxiang Wang, Xiangjin Zhang

Abstract:

This study focuses on the overload environment and dynamic response of the core components (i.e., sensors) within the fuze of a warhead-fuze system during penetration of typical targets. Considering the connection structure between the warhead and the fuze, as well as the internal structure of the fuze, a finite element model of the warhead-fuze system penetrating a semi-infinite thick concrete target was constructed using the finite element analysis software LS-DYNA for numerical simulation. The results reveal that the response signal of the sensors inside the warhead-fuze system is larger in magnitude and exhibits greater vibration disturbances compared to the acceleration signal of the warhead. Moreover, the study uncovers the dynamic response characteristics of the sensors within the warhead-fuze system under multi-condition scenarios involving different target strengths and penetration angles. The research findings provide a sound basis for the rapid and effective prediction of the dynamic response and overload characteristics of critical modules within the fuze under different working conditions, offering technical references for the integrated design of warhead-fuze systems.

Keywords: penetration, warhead-fuze system, multi-condition, acceleration overload signal, numerical simulation

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