Search results for: planar traction force

Authors: Pallab Das, Nabam Zomleen

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Effective dissipation of lateral loads that are coming due to seismic force determines the strength, durability and safety concern of the structure. Masonry infill has high stiffness and strength capabilities which can be put into an effective utilization for lateral load dissipation by incorporating it into building construction, but masonry behaves in highly nonlinear manner, so it is highly important to find out generalized, yet a rational approach to determine its nonlinear behavior and failure mode and it’s response when it is incorporated into building. But most of the countries do not specify the procedure for design of masonry infill wall. Whereas, there are many analytical modeling method available in literature, e.g. equivalent diagonal strut method, finite element modeling etc. In this paper the masonry infill is modeled and 6-storey bare framed building and building with masonry infill is analyzed using SAP-200014 in order to find out inter-storey drift by time-history analysis and capacity curve by Pushover analysis. The analysis shows that, while, the structure is well within CP performance level for both the case, whereas, there is considerable reduction of inter-storey drift of about 28%, when the building is analyzed with masonry infill wall.

Keywords: capacity curve, masonry infill, nonlinear analysis, time history analysis

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Authors: Angga S. Fajar, Y. Takahashi, J. Kiyono, S. Sawada

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The structural system concept of RC pier accompanied with multi sliding friction damping mechanism was developed based on numerical analysis approach. However in the implementation, to make design for such kind of this structural system consumes a lot of effort in case high of complexity. During making design, the special behaviors of this structural system should be considered including flexible small deformation, sufficient elastic deformation capacity, sufficient lateral force resistance, and sufficient energy dissipation. The confinement distribution of friction devices has significant influence to its. Optimization and prediction with multi function regression of this structural system expected capable of providing easier and simpler design method. The confinement distribution of friction devices is optimized with SNOPT in Opensees, while some design variables of the structure are predicted using multi function regression of ANN. Based on the optimization and prediction this structural system is able to be designed easily and simply.

Keywords: RC Pier, multi sliding friction device, optimal design, flexible small deformation

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Authors: Muhammad Alhaji Maidugu

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The role played by Arabic and Islamic Studies in the history of Nigeria - particularly Northern part of the country - cannot be overemphasized. Before the British colonialism, Arabic language was the official language in some of the great empires in Nigeria such as the Kanem Borno Empire. Islam, on the other hand, is the state religion. Both the rulers and the ruled were deeply involved in the pursuit of Arabic and Islamic knowledge traveling as far as Egypt, Saudia Arabia for scholarship. Their homes are like a modern library where Islamic books are kept and used to teach the community the different fields of Arabic and Islamic Studies. Scholars of Arabic and Islamic Studies were highly regarded and well respected in the society as they were the decision makers, diplomats and advisers to the authorities. Unfortunately, the colonizers used their influence and force to replace this language with a foreign language. In fact, they tried to exterminate it. Arabic became less important in the country. Arabic and Islamic Students became less significant and anybody studying Arabic or Islamic Studies is looked down at with disdain, and the course is considered unprofessional. This paper aims at casting a glance in the position of Arabic and Islamic Studies in Yobe State, Nigeria and social, political, economical and moral challenges faced by the students at institutions of learning.

Keywords: challenges, students of Arabic and Islamic studies, tertiary, institutions, Yobe

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Authors: Shinji Kajiwara, Tadamasa Fukuoka

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The formula project of Kinki University has been involved in the student Formula SAE of Japan (JSAE) since the second year the competition was held. The vehicle developed in the project uses a ZX-6R engine, which has been manufactured by Kawasaki Heavy Industries for the JSAE competition for the eighth time. The limited performance of the concept vehicle was improved through the development of a power train. The supercharger loading, engine dry sump, and engine cooling management of the vehicle were also enhanced. The supercharger loading enabled the vehicle to achieve a maximum output of 59.6 kW (80.6 PS)/9000 rpm and a maximum torque of 70.6 Nm (7.2 kgf m)/8000 rpm. We successfully achieved 90% of the engine’s torque band (4000–10000 rpm) with 50% of the revolutions in regular engine use (2000–12000 rpm). Using a dry sump system, we periodically managed hydraulic pressure during engine operation. A system that controls engine stoppage when hydraulic pressure falls was also constructed. Using the dry sump system at 80 mm reduced the required engine load and the vehicle’s center of gravity. Even when engine motion was suspended by the electromotive force exerted by the water pump, the circulation of cooling water was still possible. These findings enabled us to create a cooling system in accordance with the requirements of the competition.

Keywords: engine, combustion, cooling system, numerical simulation, power, torque, mechanical super charger

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Authors: Hee Jae Shin, Lee Ku Kwac, In Pyo Cha, Min Sang Lee, Hyun Kyung Yoon, Hong Gun Kim

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In rapid industrial development has increased the demand for high-strength and lightweight materials. Thus, various CFRP (Carbon Fiber Reinforced Plastics) with composite materials are being used. The design variables of CFRP are its lamination direction, order, and thickness. Thus, the hardness and strength of CFRP depend much on their design variables. In this paper, the lamination direction of CFRP was used to produce a symmetrical ply [0°/0°, -15°/+15°, -30°/+30°, -45°/+45°, -60°/+60°, -75°/+75°, and 90°/90°] and an asymmetrical ply [0°/15°, 0°/30°, 0°/45°, 0°/60° 0°/75°, and 0°/90°]. The bending flexure stress of the CFRP specimen was evaluated through a bending test. Its thermal property was measured using an infrared camera. The symmetrical specimen and the asymmetrical specimen were analyzed. The results showed that the asymmetrical specimen increased the bending loads according to the increase in the orientation angle; and from 0°, the symmetrical specimen showed a tendency opposite the asymmetrical tendency because the tensile force of fiber differs at the vertical direction of its load. Also, the infrared camera showed that the thermal property had a trend similar to that of the mechanical properties.

Keywords: Carbon Fiber Reinforced Plastic (CFRP), bending test, infrared camera, composite

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Authors: Jian Zheng

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Three-dimensional (3D) network structure has been recognized as an effective approach to enhance the mechanical and thermal conductive properties of polymeric composites. However, it has not been applied in energetic materials. In this work, a fluoropolymer based composite with vertically oriented and interconnected 3D graphite network was fabricated for polymer bonded explosives (PBXs). Here, the graphite and graphene oxide platelets were mixed, and self-assembled via rapid freezing and using crystallized ice as the template. The 3D structure was finally obtained by freezing-dry and infiltrating with the polymer. With the increasing of filler fraction and cooling rate, the thermal conductivity of the polymer composite was significantly improved to 2.15 W m⁻¹ K⁻¹ by 1094% than that of pure polymer. Moreover, the mechanical properties, such as tensile strength and elastic modulus, were enhanced by 82% and 310%, respectively, when the highly ordered structure was embedded in the polymer. We attribute the increased thermal and mechanical properties to this 3D network, which is beneficial to the effective heat conduction and force transfer. This study supports a desirable way to fabricate the strong and thermal conductive fluoropolymer composites used for the high-performance polymer bonded explosives (PBXs).

Keywords: mechanical properties, oriented network, graphite polymer composite, thermal conductivity

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Authors: Lourdes I. Meriño, Viatcheslav Kafarov, Maria Gómez

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Fuel gas used in the burner receives as contributors other gases from different processes and this result in variability in the composition, which may cause an incomplete combustion. The burners are designed to operate in a certain curve, the calorific power dependent on the pressure and gas burners. When deviation of propane and C5+ is huge, there is a large release of energy, which causes it to work out the curves of the burners, because less pressure is required to force curve into operation. That increases the risk of explosion in an oven, besides of a higher environmental impact. There should be flame detection systems, and instrumentation equipment, such as local pressure gauges located at the entrance of the gas burners, to permit verification by the operator. Additionally, distributed control systems must be configured with different combustion instruments associated with respective alarms, as well as its operational windows, and windows control guidelines of integrity, leaving the design information of this equipment. Therefore, it is desirable to analyze when a plant is taken out of service and make good operational analysis to determine the impact of changes in fuel gas streams contributors, by varying the calorific power. Hence, poor combustion is one of the cause instability in the flame of the burner and having a great impact on process safety, the integrity of individuals and teams and environment.

Keywords: combustion process, fuel composition, safety, fuel gas

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Authors: Yating Yang, Xue Zhang, Chengli Zhao

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Technology capability refers to the comprehensive ability that influences all factors of technological development. Among them, researchers’ resources serve as the foundation and driving force for technology capability, representing a significant manifestation of a country/region's technological capability. Therefore, the cross-border transfer behavior of researchers to some extent reflects changes in technological capability between countries/regions, providing a unique research perspective for technological capability assessment. This paper proposes a technological capability assessment model based on personnel transfer networks, which consists of a researchers' transfer network model and a country/region role evolution model. It evaluates the changes in a country/region's technological capability roles from the perspective of researcher transfers and conducts an analysis using artificial intelligence as a case study based on literature data. The study reveals that the United States, China, and the European Union are core nodes, and identifies the role evolution characteristics of several major countries/regions.

Keywords: transfer network, technological capability assessment, central-peripheral structure, role evolution

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Authors: Sirilak Kongkaew, Pathumwadee Yodmanee, Nopporn Kaiyawet, Arthitaya Meeprasert, Thanyada Rungrotmongkol, Toshikatsu Kaburaki, Hiroshi Noguchi, Fujio Takeuch, Nawee Kungwan, Supot Hannongbua

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Behçet’s disease (BD) is a genetic autoimmune expressed by multisystemic inflammatory disorder mostly occurred at the skin, joints, gastrointestinal tract, and genitalia, including ocular, oral, genital, and central nervous systems. Most BD patients in Japan and Korea were strongly indicated by the genetic factor namely HLA-B*51 (especially, HLA-B*51:01) marker in HMC class I, while HLA-A*26:01 allele has been detected from the BD patients in Greek, Japan, and Taiwan. To understand the selective binding of the MICA-TM peptide towards the HLAs associated with BD, the molecular dynamics simulations were applied on the four HLA alleles (B*51:01, B*35:01, A*26:01, and A*11:01) in complex with such peptide. As a result, the key residues in the binding groove of HLA protein which play an important role in the MICA-TM peptide binding and stabilization were revealed. The Van der Waals force was found to be the main protein-protein interaction. Based on the binding free energy prediction by MM/PBSA method, the MICA-TM peptide interacted stronger to the HLA alleles associated to BD in the identical class by 7-12 kcal/mol. The obtained results from the present study could help to differentiate the HLA alleles and explain a source of Behçet’s disease.

Keywords: Behçet’s disease, MD simulations, HMC class I, autoimmune

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Authors: Agus Masrukhin

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This research aims to find and analyze the model of character building in the Police Headquarters in Bali with a case study of Muslim members in improving the quality of the morality of its members. The formation of patterns of thinking, behavior, mentality, and police officers noble character, later can be used as a solution to reduce the hedonistic nature of the challenges in the era of globalization. The benefit of this study is expected to be a positive recommendation to find a constructive character building models of police officers in the Republic of Indonesia, especially Bali Police. For the long term, the discovery of the character building models can be developed for the entire police force in Indonesia. The type of research that would apply in this study researchers mix the qualitative research methods based on the narrative between the subject and the concrete experience of field research and quantitative research methods with 92 respondents from the police regional police Bali. This research used a descriptive analysis and SWOT analysis then it is presented in the FGD (focus group discussion). The results of this research indicate that the variable modeling the leadership of the police and variable police offices culture have significant influence on the implementation of spiritual development.

Keywords: positive constructive, hedonistic, character models, morality

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Authors: Shienna Marie Esteban

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The economic growth experience of the Philippines is one of the fastest in Asia. However, the said growth has not yet trickled down to every Filipino. This is evident to agricultural-dependent population. Moreover, the contribution of the agriculture sector to GDP has been dwindling while large number of labor force is still dependent on a relatively small share of GDP. As a result, poverty incidence worsened among rural poor causing hunger and malnutrition. Therefore, the existing agricultural policies in the Philippines are pushing to achieve greater food production and productivity to alleviate poverty and food insecurity. Through a review of related literature and collection and analysis of secondary data from DA, DBM, BAS - CountrySTAT, PSA, NSCB, PIDS, IRRI, UN-FAO, IFPRI, and World Bank among others, the study revealed that Philippines is still far from its goals of poverty reduction and food security. In addition, the agricultural sector is underperforming. The productivity growth of the sector comes out mediocre. The common observation is that weakness is attributed to the failures of policy and institutional environments of the agriculture sector. The policy environment failed to create a structure appropriate for the rapid growth of the sector due to institutional and governance weaknesses. A recommendation is to go through institutional and policy reforms through legislative or executive mandates should take form to improve the implementation and enforcement of existing policies.

Keywords: agriculture, food security, policy, poverty

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Authors: Sung Duk Kim, Kwan U. Kim, Jin Sim, Ryong Jin Jang

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The phenomenon of seasonal variations in the Earth’s rotation velocity was discovered in the 1930s when a crystal clock was developed and analyzed in a quantitative way for the first time between 1955 and 1968 when observation data of the seasonal variations was analyzed by an atomic clock. According to the previous investigation, atmospheric circulation is supposed to be a factor affecting the seasonal variations in the Earth’s rotation velocity in many cases, but the problem has not been solved yet. In order to solve the problem, it is necessary to apply dynamics to consider the Earth’s spatial motion, rotation, and change of shape of the Earth (movement of materials in and out of the Earth and change of the Earth’s figure) at the same time and in interrelation to the accuracy of post-Newtonian approximation regarding the Earth body as a system of mass points because the stability of the Earth’s rotation angular velocity is in the range of 10⁻⁸~10⁻⁹. For it, the equation was derived, which can consider the 3 kinds of motion above mentioned at the same time by taking the effect of the resultant external force on the Earth’s rotation into account in a relativistic way to the accuracy of post-Newtonian approximation. Therefore, the equation has been solved to obtain the theoretical values of periodic change in the Earth’s rotation velocity, and they have been compared with the astronomical observation data so to reveal the cause for the periodic change in the Earth’s rotation velocity.

Keywords: Earth rotation, moment function, periodic change, seasonal variation, relativistic change

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Authors: Oluwatosin Oyewale

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This research work seeks to take technology used for business systems as a product that requires marketing activities. Technology is invented and innovated upon in developed countries and are introduced into Africa through marketing activities. Businesses in Africa now adopt this technology for global competitiveness and hitherto unemployed but educationally advantaged people are trained in handling and utilising the technology. The aim of this study is to examine how marketing activities make this technology help in solving the unemployment problem in Africa. The areas of study are both the premier local government and the local government of the industrial haven in Ogun State, Nigeria. Area or cluster sampling technique was employed and Questionnaires were administered to two hundred respondents in the areas of study. Findings revealed that marketing has contributed to the promotion of technology; thereby making businesses globally competitive. In addition, technology has helped in reducing unemployment in developing countries. Recommendations are that training programmes that will address existing knowledge gap in technology utilisation needs to be conducted for the labour force in Africa. Moreover, adequate power supply that will aid effective utilisation of these technologies needs to be put in place by the government in these various African countries.

Keywords: marketing, unemployment, problem, panacea

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Authors: Merouane Salhi, Toufik Zebbiche, Omar Abada

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When the stagnation pressure of perfect gas increases, the specific heat and their ratio do not remain constant anymore and start to vary with this pressure. The gas does not remain perfect. Its state equation change and it becomes a real gas. In this case, the effects of molecular size and inter molecular attraction forces intervene to correct the state equation. The aim of this work is to show and discuss the effect of stagnation pressure on supersonic thermo dynamical, physical and geometrical flow parameters, to find a general case for real gas. With the assumptions that Berthelot’s state equation accounts for molecular size and inter molecular force effects, expressions are developed for analyzing supersonic flow for thermally and calorically imperfect gas lower than the dissociation molecules threshold. The designs parameters for supersonic nozzle like thrust coefficient depend directly on stagnation parameters of the combustion chamber. The application is for air. A computation of error is made in this case to give a limit of perfect gas model compared to real gas model.

Keywords: supersonic flow, real gas model, Berthelot’s state equation, Simpson’s method, condensation function, stagnation pressure

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Authors: Mohammad Parsaeimaram, Fang Congqi

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In this paper, one of the significant seismic design parameter as response modification factor in reinforced concrete (RC) buildings with base isolation system was evaluated. The seismic isolation system is a capable approach to absorbing seismic energy at the base and transfer to the substructure with lower response modification factor as compared to non-isolated structures. A response spectrum method and static nonlinear pushover analysis in according to Uniform Building Code (UBC-97), have been performed on building models involve 5, 8, 12 and 15 stories building with fixed and isolated bases consist of identical moment resisting configurations. The isolation system is composed of lead rubber bearing (LRB) was designed with help UBC-97 parameters. The force-deformation behavior of isolators was modeled as bi-linear hysteretic behavior which can be effectively used to create the isolation systems. The obtained analytical results highlight the response modification factor of considered base isolation system with higher values than recommended in the codes. The response modification factor is used in modern seismic codes to scale down the elastic response of structures.

Keywords: response modification factor, base isolation system, pushover analysis, lead rubber bearing, bi-linear hysteretic

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Authors: Indu Verma, Santanu Kumar Pal

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Interactions between DNA and adsorbed Poly (L-lysine) (PLL) on liquid crystal (LC) droplets were investigated using polarizing optical microcopy (POM) and epi-fluorescence microscopy. Earlier, we demonstrated that adsorption of PLL to the LC/aqueous interface resulted in homeotropic orientation of the LC and thus exhibited a radial configuration of the LC confined within the droplets. Subsequent adsorption of DNA (single stranded DNA/double stranded DNA) at PLL coated LC droplets was found to trigger a LC reorientation within the droplets leading to pre-radial/bipolar configuration of those droplets. To our surprise, subsequent exposure of complementary ssDNA (c-ssDNA) to ssDNA/ adsorbed PLL modified LC droplets did not cause the LC reorientation. This is likely due to the formation of polyplexes (DNA-PLL complex) as confirmed by fluorescence microscopy and atomic force microscopy. In addition, dsDNA adsorbed PLL droplets have been found to be effectively used to displace (controlled release) propidium iodide (a model drug) encapsulated within dsDNA over time. These observations suggest the potential for a label free droplet based LC detection system that can respond to DNA and may provide a simple method to develop DNA-based drug nano-carriers.

Keywords: DNA biosensor, drug delivery, interfaces, liquid crystal droplets

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Authors: Paulino Varela Tavares, Ana Lucia Romao

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Public governance represents an articulated arrangement, dynamic and interactive, present in the exercise of authority aimed at strengthening the decision-making procedure in public administration with transparency, accountability, responsiveness and capable of to emerge control and social empowerment, to pursue and achieve the objectives efficiently and with the effectiveness desired for the collectivity, respecting the laws and provide social, institutional and economic equity in society. In this context, using a multidimensional approach with the application of a questionnaire with four questions directed to twenty Counselors of the Courts of Auditors of the States (Brazil) and twenty professionals (liberals, teachers, and specialists) of the public administration in Brazil, preliminary results indicate that 70% believe that the level of transparency in public policies is low; 40% say that the government makes accountability because it is required by law, but, other instruments must be developed to force the government to account for all accounts with society; 75% say that government responsiveness is very limited because of the lack of long term planning, which is greatly affected by party political issues in Brazil. Therefore, the results, as yet, point out that Brazilian society has a huge challenge regarding the transparency, accountability, and responsiveness of governments in relation to their public policies.

Keywords: accountability, public governance, responsiveness, transparency

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Authors: Bang-Fuh Chen, Chih-Chun Chu

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The flow induced cylinder vibration or earthquake-induced cylinder motion are moving in an arbitrary direction with time. The phenomenon of flow across cylinder is highly nonlinear and a linear-superposition of flow pattern across separated oscillating direction of cylinder motion is not valid to obtain the flow pattern across a cylinder oscillating in multiple directions. A novel finite difference scheme is developed to simulate the viscous flow across an arbitrary moving circular cylinder and we call this a complete 2D (two-dimensional) flow-cylinder interaction. That is, the cylinder is simultaneously oscillating in x- and y- directions. The time-dependent domain and meshes associated with the moving cylinder are mapped to a fixed computational domain and meshes, which are time independent. The numerical results are validated by several bench mark studies. Several examples are introduced including flow across steam-wise, transverse oscillating cylinder and flow across rotating cylinder and flow across arbitrary moving cylinder. The Morison’s formula can not describe the complex interaction phenomenon between cross flow and oscillating circular cylinder. And the completed 2D computational fluid dynamic analysis should be made to obtain the correct hydrodynamic force acting on the cylinder.

Keywords: 2D cylinder, finite-difference method, flow-cylinder interaction, flow induced vibration

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Authors: Rehan Ali Shah, A. M. Siddiqui, T. Haroon

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Slip boundary value problem in wire coating analysis with heat transfer is examined. The fluid is assumed to be viscoelastic PTT (Phan-Thien and Tanner). The rheological constitutive equation of PTT fluid model simulates various polymer melts. Therefore, the current consequences are valuable in a number of realistic situations. Effects of slip parameter γ as well as εDec^2 (viscoelastic index) on the axial velocity, shear stress, normal stress, average velocity, volume flux, thickness of coated wire, shear stress, force on the total wire and temperature distribution profiles have been investigated. A new direction is explored to analyze the flow with the slip parameter. The slippage at the boundaries plays an important role in thickness of coated wire. It is noted that as the slip parameter increases the flow rate and thickness of coated wire increases while, temperature distribution decreases. The results reduce to no slip when the slip parameter is vanished. Furthermore, we can obtain the results for Maxwell and viscous model by setting ε and λ equal to zero respectively.

Keywords: wire coating, straight annular die, PTT fluid, heat transfer, slip boundary conditions

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Authors: Hatem Mrad, Mohamed Bouazara, Fouad Erchiqui

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Fatigue, is considered as one of the main cause of mechanical properties degradation of mechanical parts. Probability and reliability methods are appropriate for fatigue analysis using uncertainties that exist in fatigue material or process parameters. Current work deals with the study of the effect of the number and counting Rainflow cycle on fatigue lifetime (cumulative damage) of an upper arm of the vehicle suspension system. The major part of the fatigue damage induced in suspension arm is caused by two main classes of parameters. The first is related to the materials properties and the second is the road excitation or the applied force of the passenger’s number. Therefore, Young's modulus and road excitation are selected as input parameters to conduct repetitive simulations by Monte Carlo (MC) algorithm. Latin hypercube sampling method is used to generate these parameters. Response surface method is established according to fatigue lifetime of each combination of input parameters according to strain-life method. A PYTHON script was developed to automatize finite element simulations of the upper arm according to a design of experiments.

Keywords: fatigue, monte carlo, rainflow cycle, response surface, suspension system

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Authors: F. Laatar, S. Ktifa, H. Ezzaouia

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Plasma Enhanced Chemical Vapor Deposition (PECVD) method is used to deposit hydrogenated nanocrystalline silicon films (nc-Si: H) on Porous Anodic Alumina Films (PAF) on glass substrate at different deposition duration. Influence of the deposition time on the physical properties of nc-Si: H grown on PAF was investigated through an extensive correlation between micro-structural and optical properties of these films. In this paper, we present an extensive study of the morphological, structural and optical properties of these films by Atomic Force Microscopy (AFM), X-Ray Diffraction (XRD) techniques and a UV-Vis-NIR spectrometer. It was found that the changes in DT can modify the films thickness, the surface roughness and eventually improve the optical properties of the composite. Optical properties (optical thicknesses, refractive indexes (n), absorption coefficients (α), extinction coefficients (k), and the values of the optical transitions EG) of this kind of samples were obtained using the data of the transmittance T and reflectance R spectra’s recorded by the UV–Vis–NIR spectrometer. We used Cauchy and Wemple–DiDomenico models for the analysis of the dispersion of the refractive index and the determination of the optical properties of these films.

Keywords: hydragenated nanocrystalline silicon, plasma processing chemical vapor deposition, X-ray diffraction, optical properties

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Authors: Nazar Hussain, Debaraj Mukherjee

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Carbohydrate-derived chiral intermediates which contain arrays of defined stereocenters have found enormous applications in organic synthesis due to their inherent functional group, stereochemical and structural diversities as well as their ready availability. Stereodiversity of these classes of molecules has motivated synthetic organic chemistry over the years. One major challenge is control of relative configuration during construction of acyclic fragments. Here, we show that The Diels Alder addition of arynes to appropriately substituted vinyl/aryl glycals followed by π-extension via pyran ring opening smoothly furnished meta-disubstituted fused aromatic cores containing a stereo-defined orthogonally protected chiral side chain. The method is broad in terms of aryl homologation affording benzene, naphthalene, and phenanthrene derivatives. Base-induced deprotonation followed by cleavage of the allylic C-O bond appears to be the crucial steps leading to the development of aromaticity, which is the driving force behind the annulative π-extension process. The present protocol can be used for the synthesis of meta-disubstituted naphthalene aldehydes and substrates for aldolases.

Keywords: vinyl/C-2 aryl glycal, arynes, cyclization, ring opening

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Authors: G. Punithavathy

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The research proposes a statistical model for the distributed acoustic sensor interrogation units that broadcast a laser pulse into the fiber optics, where interactions within the fiber determine the localized acoustic energy that causes light reflections known as backscatter. The backscattered signal's amplitude and phase can be calculated using explicit equations. The created model makes amplitude signal spectrum and autocorrelation predictions that are confirmed by experimental findings. Phase signal characteristics that are useful for researching optical time domain reflectometry (OTDR) system sensing applications are provided and examined, showing good agreement with the experiment. The experiment was successfully done with the use of Python coding. In this research, we can analyze the entire distributed acoustic sensing (DAS) component parts separately. This model assumes that the fiber is in a static condition, meaning that there is no external force or vibration applied to the cable, that means no external acoustic disturbances present. The backscattered signal consists of a random noise component, which is caused by the intrinsic imperfections of the fiber, and a coherent component, which is due to the laser pulse interacting with the fiber.

Keywords: distributed acoustic sensing, optical fiber devices, optical time domain reflectometry, Rayleigh scattering

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Authors: Hassen M. Ouakad

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In this paper, the influence of van der Waals, as well as electrostatic forces on the structural behavior of MEMS and NEMS actuators, has been investigated using of a Euler-Bernoulli beam continuous model. In the proposed nonlinear model, the electrostatic fringing-fields and the mid-plane stretching (geometric nonlinearity) effects have been considered. The nonlinear integro-differential equation governing the static structural behavior of the actuator has been derived. An original Galerkin-based reduced-order model has been developed to avoid problems arising from the nonlinearities in the differential equation. The obtained reduced-order model equations have been solved numerically using the Newton-Raphson method. The basic design parameters such as the pull-in parameters (voltage and deflection at pull-in), as well as the detachment length due to the van der Waals force of some investigated micro- and nano-actuators have been calculated. The obtained numerical results have been compared with some other existing methods (finite-elements method and finite-difference method) and the comparison showed good agreement among all assumed numerical techniques.

Keywords: MEMS, NEMS, fringing-fields, mid-plane stretching, Galerkin

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Authors: Kazeem Ajasa Badmus, Zulkifli Idrus, Goh Yong Meng, Kamalludin Mamat-Hamidi

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This study was aimed at evaluating the roles played by early age in performance, organs weights, meat quality traits, and telomere length integrity. One hundred male Cobb 500® broiler chickens were grouped into ten replicates of ten chickens each. Growth performance, measurement of telomere length, weights of organs, and meat quality traits were determined on days 14, 28, and 42 of the experiment. There were significant (p < 0.05) differences obtained in the chicken growth performance across ages. Telomere length of blood, muscle, liver, and heart on day 14 were significantly (p < 0.05) shorter than telomere length obtained on days 28 and 42 of the age. Weights of organs on day 14 were significantly (p < 0.05) higher than those obtained on days 28 and 42. In this study, birds slaughtered on day 14 presented the highest (p < 0.05) pH, drip loss, redness, and yellowness. They, however, showed lower (p < 0.05) cooking loss, shear force, and lightness. There was a significant association between age, telomere length, and meat quality traits. It is therefore concluded that telomere length attrition is associated with early age metabolic activities and could be used to measure chicks' welfare.

Keywords: age, telomere length, organ weights, meat quality

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Authors: Bernard Owusu Asare

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This study investigates the implementation and efficacy of community policing within the Ghana Police Service, with a focus on its impact on local communities. Emphasizing the goal of creating safer environments and improving the overall quality of life, the research engages opinion leaders from selected communities in Ghana, as well as members of the police force stationed within these communities. Employing a semi-structured interview guide as the primary research instrument, data collection involves face-to-face interviews conducted at respondents' residences and policing centers. The preliminary findings underscore the pivotal role of collaborative efforts between community elders and police personnel in the successful execution of community policing initiatives. Furthermore, the study identifies gainful employment for the youth as a key determinant of effective policing, highlighting the interconnectedness of socioeconomic factors with law enforcement outcomes. The study further reveals that access to the internet emerges as a factor influencing both policing practices and the overall quality of life within these communities. By contextualizing the dynamics of community policing in the local Ghanaian context, this research aims to contribute valuable insights to the ongoing discourse on effective law enforcement strategies and their impact on community well-being.

Keywords: community, policing, police service, Ghana

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Authors: Van Son Nguyen, Van Huy Mai, Alec Moradpour, Pascale Auban Senzier, Claude Pasquier, Kang Wang, Pierre-Antoine Albouy, Marcelo J. Rozenberg, John Giapintzakis, Christian N. Mihailescu, Charis M. Orfanidou, Thomas Maroutian, Philippe Lecoeur, Guillaume Agnus, Pascal Aubert, Sylvain Franger, Raphaël Salot, Nathalie Brun, Katia March, David Alamarguy, Pascal ChréTien, Olivier Schneegans

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In the field of Nanoelectronics, a major research activity is being developed towards non-volatile memories. To face the limitations of existing Flash memory cells (endurance, downscaling, rapidity…), new approaches are emerging, among them resistive switching memories (Re-RAM). In this work, we analysed the behaviour of LixCoO2 oxide thin films in electrode/film/electrode devices. Preliminary results have been obtained concerning the influence of bias pulses characteristics (duration, value) on some performance parameters, such as endurance and resistance ratio (ROFF/RON). Besides, Conducting Probe Atomic Force Microscopy (CP-AFM) characterizations of the devices have been carried out to better understand some causes of performance failure, and thus help optimizing the switching performance of such devices.

Keywords: non volatile resistive memories, resistive switching, thin films, endurance

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Authors: Mrinal Saurabh Bhaskar, Rahul E Ravindranathan, Priyangana Borah

Abstract:

Energy plays a key role and as a driving force for economic and social growth for any country. To manage the energy sources and its efficient utilization in different economic sectors, energy policy of a country is critical. The energy performance of a country is measured in Energy Intensity and India’s Energy Intensity due to several policies interventions has reduced from 0.53 toe/1000USD (2010) in the year 2000 to 0.38 toe/1000USD (2010) in the year 2014, which is about 28 per cent reduction. The Government of India has taken several initiates to manage their increasing energy demand and meet the climate change goals defined by them. The major policy milestones in India related to energy are (i) Enactment of Energy Conservation (EC) Act 2001 (ii) Establishment of Bureau of Energy Efficiency 2001 (iii) National Action Plan on Climate Change (iv) Launch of Demand Side Management schemes (v) Amendment of EC Act 2010 (vi) Launch of Perform Achieve and Trade scheme 2012. Through a critical review, this paper highlights the key energy policy interventions by India, its benefits and impact, challenges faced and efforts of the Government to overcome such challenges. Such take away would be helpful for other countries who are proposing to prepare or amend their energy policy for their different economic sectors.

Keywords: energy, efficiency, climate, policy

Procedia PDF Downloads 341

Authors: Maizatulnisa Othman, Mohamad Bukhari, Zahurin Halim, Souad A. Muhammad, Khalisani Khalid

Abstract:

Sandwich structure composites produced by epoxy core and aluminium skin were developed as potential building materials. Interface bonding between core and skin was controlled by varying kenaf content. Five different weight percentage of kenaf loading ranging from 10 wt% to 50 wt% were employed in the core manufacturing in order to study the mechanical properties of the sandwich composite. Properties of skin aluminium with epoxy were found to be affected by drying time of the adhesive. Mechanical behavior of manufactured sandwich composites in relation with properties of constituent materials was studied. It was found that 30 wt% of kenaf loading contributed to increase the flexural strength and flexural modulus up to 102 MPa and 32 Gpa, respectively. Analysis were done on the flatwise and edgewise compression test. For flatwise test, it was found that 30 wt% of fiber loading could withstand maximum force until 250 kN, with compressive strength results at 96.94 MPa. However, at edgewise compression test, the sandwich composite with same fiber loading only can withstand 31 kN of the maximum load with 62 MPa of compressive strength results.

Keywords: sandwich structure composite, epoxy, aluminium, kenaf fiber

Procedia PDF Downloads 392

Authors: Xiangmei Li

Abstract:

Domestic violence (DV) victims are at a greater risk of suffering mental health problems; however, not all victims experience the same degree of depression. Women respond differently to gender inequalities based on their gender ideologies. This study explored the moderating role of gender ideology in the relation between exposure to DV and depression. Data were drawn from a sub-sample of women aged 18-60 from the Third WaveSurvey on the Social Status of Women in China (N = 10,701). The survey adopted astratified three-stage sampling design to select a representative sample of respondents from the country. Regression models were used to examine the moderating effects of gender ideology on the relation between DV and depression. Women who reported DV experience had more severe depressive symptoms after controlling for confounding social–demographic factors (β = 0.592, 95% CI: 0.489 – 0.695). Women's gender ideology moderated the association between DV severity and depression (β = -0.049, 95% CI: -0.085 – -0.013), despite being subjected to the same levels of victimization. The experience of domestic violence is a useful indicator for routine screening for depression in clinic and community settings. Interventions that aim to decrease depression caused by DV are more likely to be effective if they promote more egalitarian gender ideology to counter the mindset that a woman's role is confined to the home and a family suffers if the wife participates in the labor force.

Keywords: domestic violence against wives, depression, gender ideology, moderation

Procedia PDF Downloads 129