Search results for: structure analysis

Authors: Hamed Belloumi, Aymen Ammouri, Ferid Kourda

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A new trend in power converters is to design planar transformer that aim for low profile. However, at high frequency, the planar transformer ac losses become significant due to the proximity and skin effects. In this paper, the design and implementation of a novel planar litz conductor is presented in order to equalize the flux linkage and improving the current distribution. The developed PCB litz wire structure minimizes the losses in a similar way to the conventional multi stranded litz wires. In order to further illustrate the eddy current effect in different arrangements, a finite-element analysis (FEA) tool is used to analyze current distribution inside the conductors. Finally, the proposed planar transformer has been integrated in an electronic stage to test at high signal levels.

Keywords: planar transformer, finite-element analysis (FEA), winding losses, planar litz wire

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Authors: A. Bertašienė

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Energy harvesting from any structure makes a challenge. Different structure of air/wind flows in industrial, environmental and residential applications emerge the real flow investigation in detail. Many of the application fields are hardly achievable to the detailed description due to the lack of up-to-date statistical data analysis. In situ measurements aim crucial investments thus the simulation methods come to implement structural analysis of the flows. Different configurations of testing environment give an overview how important is the simple structure of field in limited area on efficiency of the system operation and the energy output. Several configurations of modeled working sections in air flow test facility was implemented in CFD ANSYS environment to compare experimentally and numerically air flow development stages and forms that make effects on efficiency of devices and processes. Effective form and amount of these flows under different geometry cases define the manner of instruments/devices that measure fluid flow parameters for effective operation of any system and emission flows to define. Different fluid flow regimes were examined to show the impact of fluctuations on the development of the whole volume of the flow in specific environment. The obtained results rise the discussion on how these simulated flow fields are similar to real application ones. Experimental results have some discrepancies from simulation ones due to the models implemented to fluid flow analysis in initial stage, not developed one and due to the difficulties of models to cover transitional regimes. Recommendations are essential for energy harvesting systems in both, indoor and outdoor cases. Further investigations aim to be shifted to experimental analysis of flow under laboratory conditions using state-of-the-art techniques as flow visualization tool and later on to in situ situations that is complicated, cost and time consuming study.

Keywords: fluid flow, initial region, tube coefficient, distinct shape

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Authors: Ferid Hammami

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The molecular geometries of the possible conformations of pyruvic acid-water complexes (PA-(H₂O)ₙ = 1- 4) have been fully optimized at DFT/B3LYP/6-311G ++ (d, p) levels of calculation. Among several optimized molecular clusters, the most stable molecular arrangements obtained when one, two, three, and four water molecules are hydrogen-bonded to a central pyruvic acid molecule are presented in this paper. Apposite topological and geometrical parameters are considered as primary indicators of H-bond strength. Atoms in molecules (AIM) analysis shows that pyruvic acid can form a ring structure with water, and the molecular structures are stabilized by both strong O-H...O and C-H...O hydrogen bonds. In large clusters, classical O-H...O hydrogen bonds still exist between water molecules, and a cage-like structure is built around some parts of the central molecule of pyruvic acid. The electrostatic potential energy map (MEP) and the HOMO-LUMO molecular orbital (highest occupied molecular orbital-lowest unoccupied molecular orbital) analysis has been performed for all considered complexes.

Keywords: pyruvic acid, PA-water complex, hydrogen bonding, DFT, AIM, MEP, HOMO-LUMO

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Authors: Azam Fazelpour, Saeed R. Dehghani, Vlastimil Masek, Yuri S. Muzychka

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This study employs a method based on image analyses and structure information to detect accumulated ice on known structures. The icing of marine vessels and offshore structures causes significant reductions in their efficiency and creates unsafe working conditions. Image processing methods are used to measure ice loads automatically. Most image processing methods are developed based on captured image analyses. In this method, ice loads on structures are calculated by defining structure coordinates and processing captured images. A pyramidal structure is designed with nine cylindrical bars as the known structure of experimental setup. Unsymmetrical ice accumulated on the structure in a cold room represents the actual case of experiments. Camera intrinsic and extrinsic parameters are used to define structure coordinates in the image coordinate system according to the camera location and angle. The thresholding method is applied to capture images and detect iced structures in a binary image. The ice thickness of each element is calculated by combining the information from the binary image and the structure coordinate. Averaging ice diameters from different camera views obtains ice thicknesses of structure elements. Comparison between ice load measurements using this method and the actual ice loads shows positive correlations with an acceptable range of error. The method can be applied to complex structures defining structure and camera coordinates.

Keywords: camera calibration, ice detection, ice load measurements, image processing

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Authors: Rui-Xiong Han, Rui Ge, Shao-Peng Li, Lin Bian, Liang-Rui Sun, Min-Jing Sang, Rui Ye, Ya-Ping Liu, Xiang-Zhen Zhang, Jie-Hao Zhang, Zhuo Zhang, Jian-Qing Zhang, Miao-Fu Xu

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The Chinese Accelerator Driven Sub-critical system (C-ADS) uses a high-energy proton beam to bombard the metal target and generate neutrons to deal with the nuclear waste. The Chinese ADS proton linear has two 0~10 MeV injectors and one 10~1500 MeV superconducting linac. Injector-I is studied by the Institute of High Energy Physics (IHEP) under construction in the Beijing, China. The linear accelerator consists of two accelerating cryomodules operating at the temperature of 2 Kelvin. This paper describes the structure and thermal performances analysis of the cryomodule. The analysis takes into account all the main contributors (support posts, multilayer insulation, current leads, power couplers, and cavities) to the static and dynamic heat load at various cryogenic temperature levels. The thermal simulation analysis of the cryomodule is important theory foundation of optimization and commissioning.

Keywords: C-ADS, cryomodule, structure, thermal simulation, static heat load, dynamic heat load

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Authors: Nassira Ouslimani

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The electronic structure of transition metals gives them many catalytic possibilities in many types of reactions, particularly cobalt and molybdenum. It is in this context that this study is part of the synthesis and characterization of mass catalysts based on cobalt and molybdenum Co1₋xMoO4 (X=0 and X=0.5 and X=1). The two catalysts were prepared by Co-precipitation using ammonia as a precipitating agent and one by precipitation. The samples obtained were analyzed by numerous physic-chemical analysis techniques: ATG-ATD-DSC, DRX-HT, SEM-EDX, and the elemental composition of the catalysts was verified by SAA as well as the FTIR. The ATG-DSC shows a mass loss for all the catalysts of approximately 8%, corresponding to the loss of water and the decomposition of nitrates. The DRX-HT analysis allows the detection of the two CoMoO4 phases with diffraction peaks which increase with the increase in temperature. The results of the FTIR analysis made it possible to highlight the vibration modes of the bonds of the structure of the prepared catalysts. The SEM images of the solids show very different textures with almost homogeneous surfaces with a more regular particle size distribution and a more defined grain shape. The EDX analysis showed the presence of the elements Co, Mo, and O in proportions very close to the nominal proportions. Finally, the actual composition, evaluated by SAA, is close to the theoretical composition fixed during the preparation. This testifies to the good conditions for the preparation of the catalysts by the co-precipitation method.

Keywords: catalytic, molybdenum, coprecipitation, cobalt, ammonia

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Authors: Hsiao-Wen Wang

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The split-share structure reform in China represents one of the most significant milestones in the evolution of the capital market. With the goal of converting non-tradable shares into tradable shares, the reform laid the foundation and supported the development of full-scale privatization. This study explores China’s split-share structure reform and its impact on statutory audit fees. This study finds that auditors earn a significant statutory audit fee premium after the split-share structure reform. The Big 4 auditors who provide better audit quality receive higher statutory audit fee premium than non-Big 4 auditors after the share reform, which is attributable to their brand reputation, rather than the relative market dominance.

Keywords: chinese split-share structure reform, statutory audit fees, big-4 auditors, corporate governance

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Authors: A. Bayoumi, M. Abdallah, F. Hage Chehade

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Structures on the ground surface bear impact from the tunneling-induced settlement, especially when twin tunnels are constructed. The tunneling influence on the structure is considered as a critical issue based on the construction procedure and relative position of tunnels. Lebanon is suffering from a traffic phenomenon caused by the lack of transportation systems. After several traffic counts and geotechnical investigations in Beirut city, efforts aim for the construction of tunneling systems. In this paper, we present a non-linear numerical modeling of the effect of the twin tunnels constructions on the structures located at soil surface for a particular site in Beirut. A parametric study, which concerns the geometric configuration of tunnels, the distance between their centers, the construction order, and the position of the structure, is performed. The tunnel-soil-structure interaction is analyzed by using the non-linear finite element modeling software PLAXIS 2D. The results of the surface settlement and the bending moment of the structure reveal significant influence when the structure is moved away, especially in vertical aligned tunnels.

Keywords: bending moment, elastic modulus, horizontal twin tunnels, soil, structure location, surface settlement, vertical twin tunnels

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Authors: Ganga K. V. Prakhya, V. Karthigeyan

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The paper describes the influences of the fluid and structure interaction in concrete structures that support large oil platforms in the North Sea. The dynamic interaction of the fluid both in 2D and 3D are demonstrated through a Computational Fluid Dynamics analysis in the event of explosion following a gas leak inside of the concrete column. The structural response characteristics of the column in water under dynamic conditions are quite complex involving axial, radial and circumferential modes. Fluid structure interaction (FSI) modelling showed that there are some frequencies of the column in water which are not found for a column in air. For example, it was demonstrated that one of the axial breathing modes can never be simulated without the use of FSI models. The occurrence of a shift in magnitude and time of pressure from explosion following gas leak along the height of the shaft not only excited the modes of vibration involving breathing (axial), bending and squashing (radial) modes but also magnified the forces in the column. FSI models revealed that dynamic effects resulted in dynamic amplification of loads. The results are summarized from a detailed study that was carried out by the first author for the Offshore Safety Division of Health & Safety Executive United Kingdom.

Keywords: concrete, explosion, fluid structure interaction, offshore structures

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Authors: Ming Qian, Davis Qian

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This study compares the different organization structures of Chinese and English writing discourses in the engineering and scientific fields, and recommends approaches for translators to convert the organization structures properly. Based on existing intercultural communication literature, English authors tend to deductively give their main points at the beginning, following with detailed explanations or arguments afterwards while the Chinese authors tend to place their main points inductively towards the end. In this study, this hypothesis has been verified by the authors’ Chinese-to-English translation experiences in the fields of science and engineering (e.g. journal papers, conference papers and monographs). The basic methodology used is the comparison of writings by Chinese authors with writings of the same or similar topic written by English authors in terms of organization structures. Translators should be aware of this nuance, so that instead of limiting themselves to translating the contents of an article in its original structure, they can convert the structures to fill the cross-culture gap. This approach can be controversial because if a translator changes the structure organization of a paragraph (e.g. from a 'because-therefore' inductive structure by a Chinese author to a deductive structure in English), this change of sentence order could be questioned by the original authors. For this reason, translators need to properly inform the original authors on the intercultural differences of English and Chinese writing (e.g. inductive structure versus deductive structure), and work with the original authors to maintain accuracy while converting from one structure used in a source language to another structure in the target language. The authors have incorporated these methodologies into their translation practices and work closely with the authors on the inter-cultural organization structure mapping. Translating discourse organization structure should become a standard practice in the translation process.

Keywords: discourse structure, information structure, intercultural communication, translation practice

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Authors: Jeron Maheswaran, Sudath C. Siriwardane

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In fatigue analysis, the structural detail of tubular joint has taken great attention among engineers. The DNV-RP-C203 is covering this topic quite well for simple and clear joint cases. For complex joint and geometry, where joint classification isn’t available and limitation on validity range of non-dimensional geometric parameters, the challenges become a fact among engineers. The classification of joint is important to carry out through the fatigue analysis. These joint configurations are identified by the connectivity and the load distribution of tubular joints. To overcome these problems to some extent, this paper compare the fatigue life of tubular joints in offshore jacket according to the stress concentration factors (SCF) in DNV-RP-C203 and finite element method employed Abaqus/CAE. The paper presents the geometric details, material properties and considered load history of the jacket structure. Describe the global structural analysis and identification of critical tubular joints for fatigue life estimation. Hence fatigue life is determined based on the guidelines provided by design codes. Fatigue analysis of tubular joints is conducted using finite element employed Abaqus/CAE [4] as next major step. Finally, obtained SCFs and fatigue lives are compared and their significances are discussed.

Keywords: fatigue life, stress-concentration factor, finite element analysis, offshore jacket structure

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Authors: Tingyu Zhang

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This paper utilizes the Super-SBM model to assess water resources green efficiency (WRGE) among provinces in China and investigate its spatial and temporal features, based on the characteristic framework of “economy-environment-society.” The social network analysis is employed to examine the network pattern and spatial interaction of WRGE. Further, the quadratic assignment procedure method is utilized for examining the influencing factors of the spatial association of WRGE regarding “relationship.” The study reveals that: (1) the spatial distribution of WRGE demonstrates a distribution pattern of Eastern>Western>Central; (2) a remarkable spatial association exists among provinces; however, no strict hierarchical structure is observed. The internal structure of the WRGE network is characterized by the feature of "Eastern strong and Western weak". The block model analysis discovers that the members of the “net spillover” and “two-way spillover” blocks are mostly in the eastern and central provinces; “broker” block, which plays an intermediary role, is mostly in the central provinces; and members of the “net beneficiary” block are mostly in the western region. (3) Differences in economic development, degree of urbanization, water use environment, and water management have significant impacts on the spatial connection of WRGE. This study is dedicated to the realization of regional linkages and synergistic enhancement of WRGE, which provides a meaningful basis for building a harmonious society of human and water coexistence.

Keywords: water resources green efficiency, super-SBM model, social network analysis, quadratic assignment procedure

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Authors: Mohammad Q. M. Momani

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The objective of this study is to examine whether the value relevance of ownership structure changed as the Amman Stock Exchange market conditions changed. Using data from 2005 to 2014, the study finds that the performance of portfolios that contain firms with concentrated ownership structure declines significantly during the post-crisis period. These portfolios exhibit poor performance relative to portfolios that contain firms with dispersed ownership structure during the post-crisis period. The results argue that uninspired performance of the Amman Stock Exchange during the post-crisis period, increased the incentives for controlling shareholders to expropriate. Investors recognized these incentives and discounted firms that were more likely to expropriate.

Keywords: value relevance, ownership structure, portfolio performance, Jordan, ASE

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Authors: Mahrooz Abed, Amir R. Masoodi

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Many structural lateral systems are used in tall buildings such as rigid frames, braced frames, shear walls, tubular structures and core structures. Some efficient structures for drift control and base moment reduction in tall buildings is outrigger and belt truss systems. When adopting outrigger beams in building design, their location should be in an optimum position for an economical design. A range of different strategies has been employed to identify the optimum locations of these outrigger beams under wind load. However, there is an absence of scientific research or case studies dealing with optimum outrigger location using buckling analysis. In this paper, one outrigger system is considered at the middle of height of structure. The optimum location of outrigger will be found based on the buckling load limitation. The core of structure is modeled by a clamped tapered beam. The exact stiffness matrix of tapered beam is formulated based on the Euler-Bernoulli theory. Finally, based on the buckling load of structure, the optimal location of outrigger will be found.

Keywords: tall buildings, outrigger system, buckling load, second-order effects, Euler-Bernoulli beam theory

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Authors: K. Tejasri, K. Suvarna Vani, S. Prathyusha, S. Ramya

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Proteins are chained sequences of amino acids which are brought together by the peptide bonds. Many varying formations of the chains are possible due to multiple combinations of amino acids and rotation in numerous positions along the chain. Protein structure prediction is one of the crucial goals worked towards by the members of bioinformatics and theoretical chemistry backgrounds. Among the four different structure levels in proteins, we emphasize mainly the secondary level structure. Generally, the secondary protein basically comprises alpha-helix and beta-sheets. Multi-class classification problem of data with disparity is truly a challenge to overcome and has to be addressed for the beta strands. Imbalanced data distribution constitutes a couple of the classes of data having very limited training samples collated with other classes. The secondary structure data is extracted from the protein primary sequence, and the beta-strands are predicted using suitable machine learning algorithms.

Keywords: proteins, secondary structure elements, beta-sheets, beta-strands, alpha-helices, machine learning algorithms

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Authors: Jun Su Park, Byung Kwan Oh, Jin Woo Hwang, Yousok Kim, Hyo Seon Park

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For the structural safety, the maximum stress calculated from the stress distribution of a structure is widely used. The stress distribution can be estimated by deformed shape of the structure obtained from measurement. Although the estimation of stress is strongly affected by the location and number of sensing points, most studies have conducted the stress estimation without reasonable basis on sensing plan such as the location and number of sensors. In this paper, an optimal sensing technique for estimating the stress distribution is proposed. This technique proposes the optimal location and number of sensing points for a 2-D frame structure while minimizing the error of stress distribution between analytical model and estimation by cubic smoothing splines using genetic algorithm. To verify the proposed method, the optimal sensor measurement technique is applied to simulation tests on 2-D steel frame structure. The simulation tests are performed under various loading scenarios. Through those tests, the optimal sensing plan for the structure is suggested and verified.

Keywords: genetic algorithm, optimal sensing, optimizing sensor placements, steel frame structure

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Authors: Seyed Abolhasan Naeini, Saeideh Mohammadi

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Rapid urban development leads to the construction of urban tunnels for transport. Passage of tunnels under the surface structures and utilities prompted the changes in the site conditions and hence alteration of the dynamic response of surface structures. Therefore, in this study, the effect of the interaction of tunnel-superstructure on the site response is investigated numerically. For this purpose, Fast Lagrangian Analysis of Continua (FLAC 2D) is used, and stratification and properties of soil layers are selected based on the line No 7 of Tehran subway. The superstructure is modeled both as an equivalent surcharge and the actual structure, and the results are compared. A comparison of the results shows that consideration of structure geometry is necessary for dynamic analysis and it leads to the changes in displacements and accelerations. Consequently, the geometry of the superstructure should be modeled completely instead of the application of an equivalent load. The effect of tunnel diameter and depth on the settlement of superstructures is also studied. Results show that when the tunnel depth and diameter grow, the settlements increase considerably.

Keywords: tunnel, FLAC2D, settlement, dynamic analysis

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Authors: Sasan Talebnezhad, Parviz Hamidia

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GPC and RMS analysis showed no distinct difference between PE 100 On, Off, and Reference grade. But FTIR spectra and multiple endothermic peaks obtained from SSA analysis, attributed to heterogeneity of ethylene sequence length, lamellar thickness and also the non-uniformity of short chain branching, showed sharp discrepancy and proposed a blend structure of high-density polyethylenes in PE 100 grade. Catalysis along with process parameters dictates poly blend PE 100 structure. This in-reactor blend is a mixture of compatible co-crystallized phases with different crystalinity, forming a physical semi hard and soft segment network responsible for improved impact properties in PE 100 pipe grade. We propose a new approach for PE100 evaluation that is more efficient than normal microstructure characterization.

Keywords: HDPE, pipe grade, in-reactor blend, hard and soft segments

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Authors: Boda Sreenivas, Lyathakula Ravindranath, Kanugula Srishailam, Byru Venkatram Reddy

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Extensive research into the optimized structure and molecular properties of 3-Flouro-2-methylbenzoicacid(FMB), 3-Chloro-2-methoxybenzoicacid (CMB), and 3-Bromo-2-methylbenzoicacid (BMB) was carried out using FT-IR, FT-Raman and UV-Visible spectra, as well as theoretically using the DFT approach with B3LYPfunctional in conjunction with 6-311++G(d,p) basis set. The optimized structure was determined by evaluating torsional scans about free rotation bonds. Structure parameters, harmonic vibrational frequencies, potential energy distribution(PED), and infrared and Raman intensities were computed. The computational results from the DFT approach, such asFT-IR, FT-Raman, and UV-Visible spectra, were compared with the experimental results and found good agreement. Observed and calculated frequencies agreed with an rms error of 8.42, 6.60, and 6.95 cm-1 for FMB, CMB, and BMB, respectively. Unambiguous vibrational assignments were made for all fundamentals using PED and eigenvectors. The electronic HOMO-LUMO, H-bonding, and strong conjugative interactions across different molecular entities are discussed using experimental and simulated Ultraviolet-Visible spectra. The title molecules' molecular properties such as dipole moment, mean polarizability, and first-order hyperpolarizability, were calculated to study their non-linear optical (NLO) behavior. The chemical reactivity descriptors and mapped electrostatic surface potential (MESP) were also evaluated. Natural bond orbital (NBO) analysis was used to examine the stability of molecules resulting from hyperconjugative interactions and charge delocalization.

Keywords: ftir/raman spectra, DFT, NLO, homo-lumo, NBO, halogenated benzoic acids

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Authors: Gamzegul Koca, Evrim Eveyik-Aydin

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Genre and discipline-specific knowledge of academic discourse in writing has long been acknowledged as being a core skill to achieve formidable tasks that are expected of graduate students in academic settings. Genre analysis approaches can be adopted to unveil the challenges encountered in these tasks to be able to take instructional actions addressing the aspects of graduate writing that need improvement. In an attempt to find genre-specific academic writing needs of Turkish students enrolled in a graduate program in ELT, this study examines the rhetorical structure of discussion sections of research articles written during the course load stage of their graduate studies. The 35.437-word specialized corpus of graduate papers compiled for the purpose of the study includes discussions of 58 unpublished reports of empirical studies, 31 written in MA courses and 27 in Ph.D. courses by a total of 44 graduate students. The study does sentence-based move structure analysis using the framework developed by Eveyik-Aydın, Karabacak and Akyel in a corpus-based study that analyzed the discussion moves of expert writers in published articles in ELT journals indexed by Social Sciences Citation. The coding of 1577 sentences by three graders using this framework revealed that while the graduate papers included the same moves used in published articles, the rhetorical structure of MA and Ph.D. papers showed considerable differences in terms of the frequency of occurrence of main discussion moves, including interpretation of the results and drawing implications. The implications of these findings will be discussed with respect to the needs of graduate writers and the expectations of discourse community.

Keywords: discussion moves, genre-specific rhetorical structure, move analysis, research articles, the specialized corpus of graduate papers

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Authors: Mohammadmehdi Torfehnejada, Serhan Senso

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Aftershock collapse capacity of Special Steel Moment Frames (SSMFs) is evaluated under aftershock earthquakes by considering building heights 8 and 12 stories. The assessment evaluates the residual collapse capacity under aftershock excitation when various levels of damage have been induced by the mainshock. For this purpose, incremental dynamic analysis (IDA) under aftershock follows the mainshock imposing the intended damage level. The study results indicate that aftershock collapse capacity of this structure may decrease remarkably when the structure is subjected to large mainshock damage. The capacity reduction under aftershock is finally related to the mainshock damage level through regression equations.

Keywords: aftershock collapse capacity, special steel moment frames, mainshock-aftershock sequences, incremental dynamic analysis, mainshock damage

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Authors: Helnaz Soltani, J. N. Reddy

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Presence of fluid medium interacting with a structure can lead to failure of the structure. Since developing efficient computational model for fluid-structure interaction (FSI) problems has broader impact to realistic problems encountered in aerospace industry, ship industry, oil and gas industry, and so on, one can find an increasing need to find a method in order to investigate the effect of fluid domain on structural response. A coupled finite element formulation of problems involving FSI issue is an accurate method to predict the response of structures in contact with a fluid medium. This study proposes a finite element approach in order to study the transient response of the structures interacting with a fluid medium. Since beam and plate are considered to be the fundamental elements of almost any structure, the developed method is applied to beams and plates benchmark problems in order to demonstrate its efficiency. The formulation is a combination of the various structure theories and the solid-fluid interface boundary condition, which is used to represent the interaction between the solid and fluid regimes. Here, three different beam theories as well as three different plate theories are considered to model the solid medium, and the Navier-Stokes equation is used as the theoretical equation governed the fluid domain. For each theory, a coupled set of equations is derived where the element matrices of both regimes are calculated by Gaussian quadrature integration. The main feature of the proposed methodology is to model the fluid domain as an added mass; the external distributed force due to the presence of the fluid. We validate the accuracy of such formulation by means of some numerical examples. Since the formulation presented in this study covers several theories in literature, the applicability of our proposed approach is independent of any structure geometry. The effect of varying parameters such as structure thickness ratio, fluid density and immersion depth, are studied using numerical simulations. The results indicate that maximum vertical deflection of the structure is affected considerably in the presence of a fluid medium.

Keywords: beam and plate, finite element analysis, fluid-structure interaction, transient response

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Authors: Salah Guettala, nesreddine.djafarhenni, Akram Khelaifia, Rachid Chebili

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This study assesses the impact of infill walls' layout in both plan and elevation on the seismic behavior of a 3D reinforced concrete structure situated in a high seismic zone. A pushover analysis is conducted to evaluate the structure's seismic performance with various infill wall layouts, considering capacity curves, absorbed energy, inter-story drift, and performance levels. Additionally, torsional effects on the structure are examined through linear dynamic analysis. Fiber-section-based macro-modeling is utilized to simulate the behavior of infill walls. The findings indicate that the presence of infill walls enhances lateral stiffness and alters structural behavior. Moreover, the study highlights the importance of considering the effects of infill wall layout, as non-uniform layouts can degrade building performance post-earthquake, increasing inter-story drift and risk of damage or collapse. To mitigate such risks, buildings should adopt a uniform infill wall layout. Furthermore, asymmetrical placement of masonry infill walls introduces additional torsional forces, particularly when there's a lack of such walls on the first story, potentially leading to irregular stiffness and soft-story phenomena.

Keywords: RC structures, infll walls’ layout, pushover analysis, macro-model, fiber plastic hinge, torsion

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Authors: Puwanenthiren Pratheepkanth

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This study considers whether national development level influences a firm’s voluntary intellectual capital disclosure (ICD) provided by a sample of 100 Australian and 100 Sri Lankan firms in terms of a two-years during 2015-16. This two-nation study uses a content analysis and literature-review analysis to provide an understanding of the underlying forces and issues. It was found that Australian firms tend to rely heavily on external structure disclosures (with particular attention to brands, customer loyalty, and research collaborations), but Sri Lankan relatively larger firms prefer intellectual property disclosures and the smaller firms tend to be as adept at external structure as their Australian counterparts. It was also found that the nature of a firm tends to trump the nurture of the development level of the country in which the firm is embedded. While a wider diffusion of better ICD methodology under International Financial Reporting Standard (IFRS) could improve the cost-effectiveness of financial reporting and generally increase efficiency, this is unlikely to occur until competition is more of a spur.

Keywords: developed countries, developing countries, content analysis, intellectual capital disclosure

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Authors: Minjung Kim, Hyunkoo Kang, Jinkoo Kim

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In this study, a seismic retrofit scheme for a reinforced concrete shear wall structure using steel slit dampers was presented. The stiffness and the strength of the slit damper used in the retrofit were verified by cyclic loading test. A genetic algorithm was applied to find out the optimum location of the slit dampers. The effects of the slit dampers on the seismic retrofit of the model were compared with those of jacketing shear walls. The seismic performance of the model structure with optimally positioned slit dampers was evaluated by nonlinear static and dynamic analyses. Based on the analysis results, the simple procedure for determining required damping ratio using capacity spectrum method along with the damper distribution pattern proportional to the inter-story drifts was validated. The analysis results showed that the seismic retrofit of the model structure using the slit dampers was more economical than the jacketing of the shear walls and that the capacity spectrum method combined with the simple damper distribution pattern led to satisfactory damper distribution pattern compatible with the solution obtained from the genetic algorithm.

Keywords: seismic retrofit, slit dampers, genetic algorithm, jacketing, capacity spectrum method

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Authors: Bita Mohajernia, R. J. Urbanic

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Mold making techniques have focused on meeting the customers’ functional and process requirements; however, today, molds are increasing in size and sophistication, and are difficult to manufacture, transport, and set up due to their size and mass. Presently, mold weight saving techniques focus on pockets to reduce the mass of the mold, but the overall size is still large, which introduces costs related to the stock material purchase, processing time for process planning, machining and validation, and excess waste materials. Reducing the overall size of the mold is desirable for many reasons, but the functional requirements, tool life, and durability cannot be compromised in the process. It is proposed to use Finite Element Analysis simulation tools to model the forces, and pressures to determine where the material can be removed. The potential results of this project will reduce manufacturing costs. In this study, a light weight structure is defined by an optimal distribution of material to carry external loads. The optimization objective of this research is to determine methods to provide the optimum layout for the mold structure. The topology optimization method is utilized to improve structural stiffness while decreasing the weight using the OptiStruct software. The optimized CAD model is compared with the primary geometry of the mold from the NX software. Results of optimization show an 8% weight reduction while the actual performance of the optimized structure, validated by physical testing, is similar to the original structure.

Keywords: finite element analysis, plastic injection molding, topology optimization, weight reduction

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Authors: Geraldine Giraldo

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In the research of advanced materials, ceramics based on KNN are an important topic, especially for multifunctional applications. In this work, the physical, structural, and microstructural properties of the (KNN-CaLi-xSm) system were analyzed by varying the concentration of samarium, which was prepared using the conventional solid-state reaction method by mixing oxides. It was found that the increase in Sm+3 concentration led to higher porosity in the sample and, consequently, a decrease in density, which is attributed to the structural vacancies at the A-sites of the perovskite-type structure of the ceramic system. In the structural analysis, a coexistence of Tetragonal (T) and Orthorhombic (O) phases were observed at different rare-earth ion contents, with a higher content of the T phase at xSm=0.010. Furthermore, the structural changes in the calcined powders at different temperatures were studied using the results of DTA-TG, which allowed for the analysis of the system's composition. It was found that the lowest total decomposition temperature occurred when xSm=0.010 at 770°C.

Keywords: perovskite, piezoelectric, multifunctional, Structure, ceramic

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Authors: J. Kundrák, I. Sztankovics, K. Gyáni

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In addition to the increase of the material removal rate or surface rate, or the improvement of the surface quality, which are the main aims of the development of manufacturing technology, a growing number of other manufacturing requirements have appeared in the machining of workpiece surfaces. Among these, it is becoming increasingly dominant to generate a surface topography in finishing operations which meet more closely the needs of operational requirements. These include the examination of the surface periodicity and/or ensuring that the twist structure values are within the limits (or even preventing its occurrence) in specified cases such as on the sealing surfaces of rotating shafts or on the inside working surfaces of needle roller bearings. In the view of the measurement, the twist has different parameters from surface roughness, which must be determined for the machining procedures. Therefore in this paper the alteration of the theoretical values of the parameters determining twist structure are studied as a function of the kinematic properties.

Keywords: kinematic parameters, rotational turning, surface topography, twist structure

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Authors: Nikhil Gopalkrishnan, Praveen Bhaskaran, Aditya Bhargava, Gyandeep Bhumarkar

Abstract:

The present paper is an attempt to perform various Non-Destructive Tests on concrete structure as NDT is gaining a wide importance in the branch of civil engineering these days. Various tests that are performed under NDT not only enable us to determine the strength of concrete structure, but also provide us in-hand information regarding the durability, in-situ properties of the concrete structure. Keeping these points in our mind, we have focused our views on performing a case study to show the comparison between the NDT test results performed on a particular concrete structure and another structure at the same site which is subjected to a continuous fire of say 48-72 hours. The mix design and concrete grade of both the structures were same before the one was affected by fire. The variations in the compressive strength, concrete quality and in-situ properties of the two structures have been discussed in this paper. NDT tests namely Ultrasonic Pulse Velocity Test, Rebound Hammer Test, Core-Cutter Test was performed at both the sites. The main objective of this research is to analyze the variations in the strength and quality of the concrete structure which is subjected to a high temperature fire and the one which isn’t exposed to it.

Keywords: core-cutter test, non-destructive test, rebound hammer test, ultrasonic pulse velocity test

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Authors: Alexander Hudson, Shaogang Gong

Abstract:

Structure determination is key to understanding protein function at a molecular level. Whilst significant advances have been made in predicting structure and function from amino acid sequence, researchers must still rely on expensive, time-consuming analytical methods to visualise detailed protein conformation. In this study, we demonstrate that it is possible to make accurate (≥80%) predictions of protein class and architecture from structures determined at low (>3A) resolution, using a deep convolutional neural network trained on high-resolution (≤3A) structures represented as 2D matrices. Thus, we provide proof of concept for high-speed, low-cost protein structure classification at low resolution, and a basis for extension to prediction of function. We investigate the impact of the input representation on classification performance, showing that side-chain information may not be necessary for fine-grained structure predictions. Finally, we confirm that high resolution, low-resolution and NMR-determined structures inhabit a common feature space, and thus provide a theoretical foundation for boosting with single-image super-resolution.

Keywords: transfer learning, protein distance maps, protein structure classification, neural networks

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