Search results for: traditional similarity transformation model
Commenced in January 2007
Frequency: Monthly
Edition: International
Paper Count: 21749

Search results for: traditional similarity transformation model

20159 An Inquiry on 2-Mass and Wheeled Mobile Robot Dynamics

Authors: Boguslaw Schreyer

Abstract:

In this paper, a general dynamical model is derived using the Lagrange formalism. The two masses: sprang and unsprang are included in a six-degree of freedom model for a sprung mass. The unsprung mass is included and shown only in a simplified model, although its equations have also been derived by an author. The simplified equations, more suitable for the computer model of robot’s dynamics are also shown.

Keywords: dynamics, mobile, robot, wheeled mobile robots

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20158 Yaw Angle Effect on the Aerodynamic Performance of Rear-Roof Spoiler of Hatchback Vehicle

Authors: See-Yuan Cheng, Kwang-Yhee Chin, Shuhaimi Mansor

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Rear-roof spoiler is commonly used for improving the aerodynamic performance of road vehicles. This study aims to investigate the effect of yaw angle on the effectiveness of strip-type rear-roof spoiler in providing lower drag and lift coefficients of a hatchback model. A computational fluid dynamics (CFD) method was used. The numerically obtained results were compared to the experimental data for validation of the CFD method. At increasing yaw angle, both the drag and lift coefficients of the model were to increase. In addition, the effectiveness of spoiler was deteriorated. These unfavorable effects were due to the formation of longitudinal vortices around the side edges of the model that had caused the surface pressure of the model to drop. Furthermore, there were significant crossflow structures developed behind the model at larger yaw angle, which were associated with the drop in the surface pressure of the rear section of the model and cause the drag coefficient to rise.

Keywords: Ahmed model, aerodynamics, spoiler, yaw angle

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20157 Modern Work Modules in Construction Practice

Authors: Robin Becker, Nane Roetmann, Manfred Helmus

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Construction companies lack junior staff for construction management. According to a nationwide survey of students, however, the profession lacks attractiveness. The conflict between the traditional job profile and the current desires of junior staff for contemporary and flexible working models must be resolved. Increasing flexibility is essential for the future viability of small and medium-sized enterprises. The implementation of modern work modules can help here. The following report will present the validation results of the developed work modules in construction practice.

Keywords: modern construction management, construction industry, work modules, shortage of junior staff, sustainable personnel management, making construction management more attractive, working time model

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20156 Analytical Solutions of Josephson Junctions Dynamics in a Resonant Cavity for Extended Dicke Model

Authors: S.I.Mukhin, S. Seidov, A. Mukherjee

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The Dicke model is a key tool for the description of correlated states of quantum atomic systems, excited by resonant photon absorption and subsequently emitting spontaneous coherent radiation in the superradiant state. The Dicke Hamiltonian (DH) is successfully used for the description of the dynamics of the Josephson Junction (JJ) array in a resonant cavity under applied current. In this work, we have investigated a generalized model, which is described by DH with a frustrating interaction term. This frustrating interaction term is explicitly the infinite coordinated interaction between all the spin half in the system. In this work, we consider an array of N superconducting islands, each divided into two sub-islands by a Josephson Junction, taken in a charged qubit / Cooper Pair Box (CPB) condition. The array is placed inside the resonant cavity. One important aspect of the problem lies in the dynamical nature of the physical observables involved in the system, such as condensed electric field and dipole moment. It is important to understand how these quantities behave with time to define the quantum phase of the system. The Dicke model without frustrating term is solved to find the dynamical solutions of the physical observables in analytic form. We have used Heisenberg’s dynamical equations for the operators and on applying newly developed Rotating Holstein Primakoff (HP) transformation and DH we have arrived at the four coupled nonlinear dynamical differential equations for the momentum and spin component operators. It is possible to solve the system analytically using two-time scales. The analytical solutions are expressed in terms of Jacobi's elliptic functions for the metastable ‘bound luminosity’ dynamic state with the periodic coherent beating of the dipoles that connect the two double degenerate dipolar ordered phases discovered previously. In this work, we have proceeded the analysis with the extended DH with a frustrating interaction term. Inclusion of the frustrating term involves complexity in the system of differential equations and it gets difficult to solve analytically. We have solved semi-classical dynamic equations using the perturbation technique for small values of Josephson energy EJ. Because the Hamiltonian contains parity symmetry, thus phase transition can be found if this symmetry is broken. Introducing spontaneous symmetry breaking term in the DH, we have derived the solutions which show the occurrence of finite condensate, showing quantum phase transition. Our obtained result matches with the existing results in this scientific field.

Keywords: Dicke Model, nonlinear dynamics, perturbation theory, superconductivity

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20155 Elucidation of Dynamics of Murine Double Minute 2 Shed Light on the Anti-cancer Drug Development

Authors: Nigar Kantarci Carsibasi

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Coarse-grained elastic network models, namely Gaussian network model (GNM) and Anisotropic network model (ANM), are utilized in order to investigate the fluctuation dynamics of Murine Double Minute 2 (MDM2), which is the native inhibitor of p53. Conformational dynamics of MDM2 are elucidated in unbound, p53 bound, and non-peptide small molecule inhibitor bound forms. With this, it is aimed to gain insights about the alterations brought to global dynamics of MDM2 by native peptide inhibitor p53, and two small molecule inhibitors (HDM201 and NVP-CGM097) that are undergoing clinical stages in cancer studies. MDM2 undergoes significant conformational changes upon inhibitor binding, carrying pieces of evidence of induced-fit mechanism. Small molecule inhibitors examined in this work exhibit similar fluctuation dynamics and characteristic mode shapes with p53 when complexed with MDM2, which would shed light on the design of novel small molecule inhibitors for cancer therapy. The results showed that residues Phe 19, Trp 23, Leu 26 reside in the minima of slowest modes of p53, pointing to the accepted three-finger binding model. Pro 27 displays the most significant hinge present in p53 and comes out to be another functionally important residue. Three distinct regions are identified in MDM2, for which significant conformational changes are observed upon binding. Regions I (residues 50-77) and III (residues 90-105) correspond to the binding interface of MDM2, including (α2, L2, and α4), which are stabilized during complex formation. Region II (residues 77-90) exhibits a large amplitude motion, being highly flexible, both in the absence and presence of p53 or other inhibitors. MDM2 exhibits a scattered profile in the fastest modes of motion, while binding of p53 and inhibitors puts restraints on MDM2 domains, clearly distinguishing the kinetically hot regions. Mode shape analysis revealed that the α4 domain controls the size of the cleft by keeping the cleft narrow in unbound MDM2; and open in the bound states for proper penetration and binding of p53 and inhibitors, which points to the induced-fit mechanism of p53 binding. P53 interacts with α2 and α4 in a synchronized manner. Collective modes are shifted upon inhibitor binding, i.e., second mode characteristic motion in MDM2-p53 complex is observed in the first mode of apo MDM2; however, apo and bound MDM2 exhibits similar features in the softest modes pointing to pre-existing modes facilitating the ligand binding. Although much higher amplitude motions are attained in the presence of non-peptide small molecule inhibitor molecules as compared to p53, they demonstrate close similarity. Hence, NVP-CGM097 and HDM201 succeed in mimicking the p53 behavior well. Elucidating how drug candidates alter the MDM2 global and conformational dynamics would shed light on the rational design of novel anticancer drugs.

Keywords: cancer, drug design, elastic network model, MDM2

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20154 Research Action Fields at the Nexus of Digital Transformation and Supply Chain Management: Findings from Practitioner Focus Group Workshops

Authors: Brandtner Patrick, Staberhofer Franz

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Logistics and Supply Chain Management are of crucial importance for organisational success. In the era of Digitalization, several implications and improvement potentials for these domains arise, which at the same time could lead to decreased competitiveness and could endanger long-term company success if ignored or neglected. However, empirical research on the issue of Digitalization and benefits purported to it by practitioners is scarce and mainly focused on single technologies or separate, isolated Supply Chain blocks as e.g. distribution logistics or procurement only. The current paper applies a holistic focus group approach to elaborate practitioner use cases at the nexus of the concepts of Supply Chain Management (SCM) and Digitalization. In the course of three focus group workshops with over 45 participants from more than 20 organisations, a comprehensive set of benefit entitlements and areas for improvement in terms of applying digitalization to SCM is developed. The main results of the paper indicate the relevance of Digitalization being realized in practice. In the form of seventeen concrete research action fields, the benefit entitlements are aggregated and transformed into potential starting points for future research projects in this area. The main contribution of this paper is an empirically grounded basis for future research projects and an overview of actual research action fields from practitioners’ point of view.

Keywords: digital supply chain, digital transformation, supply chain management, value networks

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20153 Modern Methods of Technology and Organization of Production of Construction Works during the Implementation of Construction 3D Printers

Authors: Azizakhanim Maharramli

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The gradual transition from entrenched traditional technology and organization of construction production to innovative additive construction technology inevitably meets technological, technical, organizational, labour, and, finally, social difficulties. Therefore, the chosen nodal method will lead to the elimination of the above difficulties, combining some of the usual methods of construction and the myth in world practice that the labour force is subjected to a strong stream of reduction. The nodal method of additive technology will create favourable conditions for the optimal degree of distribution of labour across facilities due to the consistent performance of homogeneous work and the introduction of additive technology and traditional technology into construction production.

Keywords: parallel method, sequential method, stream method, combined method, nodal method

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20152 Investigated Optimization of Davidson Path Loss Model for Digital Terrestrial Television (DTTV) Propagation in Urban Area

Authors: Pitak Keawbunsong, Sathaporn Promwong

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This paper presents an investigation on the efficiency of the optimized Davison path loss model in order to look for a suitable path loss model to design and planning DTTV propagation for small and medium urban areas in southern Thailand. Hadyai City in Songkla Province is chosen as the case study to collect the analytical data on the electric field strength. The optimization is conducted through the least square method while the efficiency index is through the statistical value of relative error (RE). The result of the least square method is the offset and slop of the frequency to be used in the optimized process. The statistical result shows that RE of the old Davidson model is at the least when being compared with the optimized Davison and the Hata models. Thus, the old Davison path loss model is the most accurate that further becomes the most optimized for the plan on the propagation network design.

Keywords: DTTV propagation, path loss model, Davidson model, least square method

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20151 Quantum Mechanism Approach for Non-Ruin Probability and Comparison of Path Integral Method and Stochastic Simulations

Authors: Ahmet Kaya

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Quantum mechanism is one of the most important approaches to calculating non-ruin probability. We apply standard Dirac notation to model given Hamiltonians. By using the traditional method and eigenvector basis, non-ruin probability is found for several examples. Also, non-ruin probability is calculated for two different Hamiltonian by using the tensor product. Finally, the path integral method is applied to the examples and comparison is made for stochastic simulations and path integral calculation.

Keywords: quantum physics, Hamiltonian system, path integral, tensor product, ruin probability

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20150 Research on Online Consumption of College Students in China with Stimulate-Organism-Reaction Driven Model

Authors: Wei Lu

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With the development of information technology in China, network consumption is becoming more and more popular. As a special group, college students have a high degree of education and distinct opinions and personalities. In the future, the key groups of network consumption have gradually become the focus groups of network consumption. Studying college students’ online consumption behavior has important theoretical significance and practical value. Based on the Stimulus-Organism-Response (SOR) driving model and the structural equation model, this paper establishes the influencing factors model of College students’ online consumption behavior, evaluates and amends the model by using SPSS and AMOS software, analyses and determines the positive factors of marketing college students’ consumption, and provides an effective basis for guiding and promoting college student consumption.

Keywords: college students, online consumption, stimulate-organism-reaction driving model, structural equation model

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20149 Seismic Performance Evaluation of Existing Building Using Structural Information Modeling

Authors: Byungmin Cho, Dongchul Lee, Taejin Kim, Minhee Lee

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The procedure for the seismic retrofit of existing buildings includes the seismic evaluation. In the evaluation step, it is assessed whether the buildings have satisfactory performance against seismic load. Based on the results of that, the buildings are upgraded. To evaluate seismic performance of the buildings, it usually goes through the model transformation from elastic analysis to inelastic analysis. However, when the data is not delivered through the interwork, engineers should manually input the data. In this process, since it leads to inaccuracy and loss of information, the results of the analysis become less accurate. Therefore, in this study, the process for the seismic evaluation of existing buildings using structural information modeling is suggested. This structural information modeling makes the work economic and accurate. To this end, it is determined which part of the process could be computerized through the investigation of the process for the seismic evaluation based on ASCE 41. The structural information modeling process is developed to apply to the seismic evaluation using Perform 3D program usually used for the nonlinear response history analysis. To validate this process, the seismic performance of an existing building is investigated.

Keywords: existing building, nonlinear analysis, seismic performance, structural information modeling

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20148 Beliefs and Rituals among the Urak Lawoi Sea Gypsies in the Bulon Archipelago, Satun Province

Authors: Srisuporn Piyaratanawong, Suchai Assawapantanakul

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This study aims to reflect changes in beliefs and rituals among the Urak Lawoi sea gypsies on the Bulon archipelago of Satun Province that are related to changes of society according to each dimension of time. The historical study was conducted using an oral history approach. The study found that the traditional way of life as itinerants who moved seasonally resulted in their dependence on nature and beliefs in supernatural power, and mysterious powers and superstitions in the belief of ghosts, ancestors, guardian spirits, large banyan trees, life and living, treatment of diseases, king of nagas, and other beliefs. They displayed their respect to supernatural powers through rituals by worshiping, making offerings to spirits and performing Rongeng dance for spirits in return for fulfilling their vows. After World War II (1945), the Urak Lawoi sea gypsies on Bulon archipelago changed their itinerant way of life to permanent settlements. However, their beliefs in supernatural powers and ritual performances remained in existence. Until 1987, when tourism began to spread to the archipelago, some of them gradually turned to make a living with tourism. Moreover, during the last 20 years (from around 1994), Islam has spread among the people. With this social context, the traditional beliefs in supernatural powers have changed to beliefs according to the religion and the way of life that has changed. Thus, when the traditional beliefs and rituals can no longer fulfil the new way of life, they slowly disappear, such as the floating the boat ceremony that has been replaced with new beliefs and rituals according to Islam. Nevertheless, some beliefs and rituals still exist, such as beliefs about treatment of diseases and Rongeng dance for spirits in return for vow fulfilling. In conclusion, the traditional beliefs and rituals of the Urak Lawoi sea gypsies on the Bulon archipelago cannot fulfil the new way of life, and have, thus, brought about changes in beliefs and rituals that are congruent with the current society.

Keywords: belief, ritual, Urak Lawoi, sea gypsy, Bulon Archipelago

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20147 Modeling Discrimination against Gay People: Predictors of Homophobic Behavior against Gay Men among High School Students in Switzerland

Authors: Patrick Weber, Daniel Gredig

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Background and Purpose: Research has well documented the impact of discrimination and micro-aggressions on the wellbeing of gay men and, especially, adolescents. For the prevention of homophobic behavior against gay adolescents, however, the focus has to shift on those who discriminate: For the design and tailoring of prevention and intervention, it is important to understand the factors responsible for homophobic behavior such as, for example, verbal abuse. Against this background, the present study aimed to assess homophobic – in terms of verbally abusive – behavior against gay people among high school students. Furthermore, it aimed to establish the predictors of the reported behavior by testing an explanatory model. This model posits that homophobic behavior is determined by negative attitudes and knowledge. These variables are supposed to be predicted by the acceptance of traditional gender roles, religiosity, orientation toward social dominance, contact with gay men, and by the perceived expectations of parents, friends and teachers. These social-cognitive variables in turn are assumed to be determined by students’ gender, age, immigration background, formal school level, and the discussion of gay issues in class. Method: From August to October 2016, we visited 58 high school classes in 22 public schools in a county in Switzerland, and asked the 8th and 9th year students on three formal school levels to participate in survey about gender and gay issues. For data collection, we used an anonymous self-administered questionnaire filled in during class. Data were analyzed using descriptive statistics and structural equation modelling (Generalized Least Square Estimates method). The sample included 897 students, 334 in the 8th and 563 in the 9th year, aged 12–17, 51.2% being female, 48.8% male, 50.3% with immigration background. Results: A proportion of 85.4% participants reported having made homophobic statements in the 12 month before survey, 4.7% often and very often. Analysis showed that respondents’ homophobic behavior was predicted directly by negative attitudes (β=0.20), as well as by the acceptance of traditional gender roles (β=0.06), religiosity (β=–0.07), contact with gay people (β=0.10), expectations of parents (β=–0.14) and friends (β=–0.19), gender (β=–0.22) and having a South-East-European or Western- and Middle-Asian immigration background (β=0.09). These variables were predicted, in turn, by gender, age, immigration background, formal school level, and discussion of gay issues in class (GFI=0.995, AGFI=0.979, SRMR=0.0169, CMIN/df=1.199, p>0.213, adj. R2 =0.384). Conclusion: Findings evidence a high prevalence of homophobic behavior in the responding high school students. The tested explanatory model explained 38.4% of the assessed homophobic behavior. However, data did not found full support of the model. Knowledge did not turn out to be a predictor of behavior. Except for the perceived expectation of teachers and orientation toward social dominance, the social-cognitive variables were not fully mediated by attitudes. Equally, gender and immigration background predicted homophobic behavior directly. These findings demonstrate the importance of prevention and provide also leverage points for interventions against anti-gay bias in adolescents – also in social work settings as, for example, in school social work, open youth work or foster care.

Keywords: discrimination, high school students, gay men, predictors, Switzerland

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20146 Challenges and Opportunities for M-Government Implementation in Saudi Arabia

Authors: A. Alssbaiheen, S. Love

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Mobile government (m-government) is one of the promising technologies for developing the governance of developing countries. While developing countries often have less advanced internet infrastructure compared to the developed world, mobile phone penetration is very high in the Gulf Cooperation Council (GCC) countries and mobile internet use offers a means to transcend traditional logistical barriers to accessing government services. The study explores the challenges and opportunities of the mobile government in Saudi Arabia. Semi-structured interviews were conducted with a diverse cohort of Saudi mobile users. A total of 77 semi-structured interviews were collected and subsequently analysed using open, axial, and selective coding. The participants’ responses revealed that many opportunities exist for the development of m-government in Saudi Arabia, including high popular awareness of government initiatives in e-government, and willingness to use such services, largely due to the time-saving and convenience aspects it offers compared with traditional bureaucratic services. However, numerous barriers were identified, including the low quality and speed of the internet, service customization, and concerns about privacy data security. It was also felt that in addition to infrastructure challenges, the traditional bureaucratic attitude of government department would itself hinder the effective deployment and utilization of m-government services.

Keywords: awareness, barriers, challenges, government services, mobile government, m-government, opportunities

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20145 The Application of Transcranial Direct Current Stimulation (tDCS) Combined with Traditional Physical Therapy to Address Upper Limb Function in Chronic Stroke: A Case Study

Authors: Najmeh Hoseini

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Strokerecovery happens through neuroplasticity, which is highly influenced by the environment, including neuro-rehabilitation. Transcranial direct current stimulation (tDCS) may enhance recovery by modulating neuroplasticity. With tDCS, weak direct currents are applied noninvasively to modify excitability in the cortical areas under its electrodes. Combined with functional activities, this may facilitate motor recovery in neurologic disorders such as stroke. The purpose of this case study was to examine the effect of tDCS combined with 30 minutes of traditional physical therapy (PT)on arm function following a stroke. A 29-year-old male with chronic stroke involving the left middle cerebral artery territory went through the treatment protocol. Design The design included 5 weeks of treatment: 1 week of traditional PT, 2 weeks of sham tDCS combined with traditional PT, and 2 weeks of tDCS combined with traditional PT. PT included functional electrical stimulation (FES) of wrist extensors followed by task-specific functional training. Dual hemispheric tDCS with 1 mA intensity was applied on the sensorimotor cortices for the first 20 min of the treatment combined with FES. Assessments before and after each treatment block included Modified Ashworth Scale, ChedokeMcmaster Arm and Hand inventory, Action Research Arm Test (ARAT), and the Box and Blocks Test. Results showed reduced spasticity in elbow and wrist flexors only after tDCS combination weeks (+1 to 0). The patient demonstrated clinically meaningful improvements in gross motor and fine motor control over the duration of the study; however, components of the ARAT that require fine motor control improved the greatest during the experimental block. Average time improvement compared to baseline was26.29 s for tDCS combination weeks, 18.48 s for sham tDCS, and 6.83 for PT standard of care weeks. Combining dual hemispheric tDCS with the standard of care PT demonstrated improvements in hand dexterity greater than PT alone in this patient case.

Keywords: tDCS, stroke, case study, physical therapy

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20144 Cultural Approach to Batak Toba Folklore

Authors: Maritess A. Rulona

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Cultural appropriation on traditional symbols has been a worldwide problem. Indonesia’s Batak Toba, an indigenous people group has experienced such appropriation. Bataknese has rich cultural heritage and oral traditions. Their cultural symbols originated from their folklores namely myths, legends, and folktales. This research used both oral traditions and cultural symbols of Batak Toba for a comparative analysis of their ancient and modern practices. This is anchored on Franz Boas’ Cultural Relativism in analyzing their five common cultural symbols. Further, it also utilized Stith Thompson’s Motif-Index to determine the common motif evident in their ten folklores. Ten Batak Toba key respondents provided information in this study. Some informants were also featured in the 20-minute documentary of this study. Thus, the findings were: 1) Traditional customs such as weddings, burial, and reburial are still observed using their cultural symbols; 2) The five most common cultural symbols are Ulos Ragidup, Sigale Gale, Rumah Bolon, Lake Toba, and Gondang; and 3) Batak culture values animals such as buffalo, lizard, and goldfish since they have ancient beliefs of mythical creatures; In conclusion, this study proved that there is a clear connection between the tribe’s oral traditions and cultural symbols. With these findings, this study recommends that elder Bataks teach younger Batak to be immersed in the cultural practices and to incorporate their traditional practices in their modern events.

Keywords: batak toba, cultural appropriation, motif-index, oral tradition, cultural emblems

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20143 Development of an Image-Based Biomechanical Model for Assessment of Hip Fracture Risk

Authors: Masoud Nasiri Sarvi, Yunhua Luo

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Low-trauma hip fracture, usually caused by fall from standing height, has become a main source of morbidity and mortality for the elderly. Factors affecting hip fracture include sex, race, age, body weight, height, body mass distribution, etc., and thus, hip fracture risk in fall differs widely from subject to subject. It is therefore necessary to develop a subject-specific biomechanical model to predict hip fracture risk. The objective of this study is to develop a two-level, image-based, subject-specific biomechanical model consisting of a whole-body dynamics model and a proximal-femur finite element (FE) model for more accurately assessing the risk of hip fracture in lateral falls. Required information for constructing the model is extracted from a whole-body and a hip DXA (Dual Energy X-ray Absorptiometry) image of the subject. The proposed model considers all parameters subject-specifically, which will provide a fast, accurate, and non-expensive method for predicting hip fracture risk.

Keywords: bone mineral density, hip fracture risk, impact force, sideways falls

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20142 Physical Education Teacher's Interpretation toward Teaching Games for Understanding Model

Authors: Soni Nopembri

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The objective of this research is to evaluate the implementation of teaching games for Understanding model by conducting action to physical education teacher who have got long teaching experience. The research applied Participatory Action Research. The subjects of this research were 19 physical education teachers who had got training of Teaching Games for Understanding. Data collection was conducted intensively through a questionnaire, in-depth interview, Focus Group Discussion (FGD), observation, and documentation. The collected data was analysis zed qualitatively and quantitatively. The result showed that physical education teachers had got an appropriate interpretation on TGfU model. Some indicators that were the focus of this research indicated this points; they are: (1) physical education teachers had good understanding toward TGfU model, (2) PE teachers’ competence in applying TGfU model on Physical Education at school were adequate, though some improvement were needed, (3) the influence factors in the implementation of TGfU model, in sequence, were teacher, facilities, environment, and students factors, (4) PE teachers’ perspective toward TGfU model were positively good, although some teachers were less optimistic toward the development of TGfU model in the future.

Keywords: TGfU, physical education teacher, teaching games, FGD

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20141 A Numerical Hybrid Finite Element Model for Lattice Structures Using 3D/Beam Elements

Authors: Ahmadali Tahmasebimoradi, Chetra Mang, Xavier Lorang

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Thanks to the additive manufacturing process, lattice structures are replacing the traditional structures in aeronautical and automobile industries. In order to evaluate the mechanical response of the lattice structures, one has to resort to numerical techniques. Ansys is a globally well-known and trusted commercial software that allows us to model the lattice structures and analyze their mechanical responses using either solid or beam elements. In this software, a script may be used to systematically generate the lattice structures for any size. On the one hand, solid elements allow us to correctly model the contact between the substrates (the supports of the lattice structure) and the lattice structure, the local plasticity, and the junctions of the microbeams. However, their computational cost increases rapidly with the size of the lattice structure. On the other hand, although beam elements reduce the computational cost drastically, it doesn’t correctly model the contact between the lattice structures and the substrates nor the junctions of the microbeams. Also, the notion of local plasticity is not valid anymore. Moreover, the deformed shape of the lattice structure doesn’t correspond to the deformed shape of the lattice structure using 3D solid elements. In this work, motivated by the pros and cons of the 3D and beam models, a numerically hybrid model is presented for the lattice structures to reduce the computational cost of the simulations while avoiding the aforementioned drawbacks of the beam elements. This approach consists of the utilization of solid elements for the junctions and beam elements for the microbeams connecting the corresponding junctions to each other. When the global response of the structure is linear, the results from the hybrid models are in good agreement with the ones from the 3D models for body-centered cubic with z-struts (BCCZ) and body-centered cubic without z-struts (BCC) lattice structures. However, the hybrid models have difficulty to converge when the effect of large deformation and local plasticity are considerable in the BCCZ structures. Furthermore, the effect of the junction’s size of the hybrid models on the results is investigated. For BCCZ lattice structures, the results are not affected by the junction’s size. This is also valid for BCC lattice structures as long as the ratio of the junction’s size to the diameter of the microbeams is greater than 2. The hybrid model can take into account the geometric defects. As a demonstration, the point clouds of two lattice structures are parametrized in a platform called LATANA (LATtice ANAlysis) developed by IRT-SystemX. In this process, for each microbeam of the lattice structures, an ellipse is fitted to capture the effect of shape variation and roughness. Each ellipse is represented by three parameters; semi-major axis, semi-minor axis, and angle of rotation. Having the parameters of the ellipses, the lattice structures are constructed in Spaceclaim (ANSYS) using the geometrical hybrid approach. The results show a negligible discrepancy between the hybrid and 3D models, while the computational cost of the hybrid model is lower than the computational cost of the 3D model.

Keywords: additive manufacturing, Ansys, geometric defects, hybrid finite element model, lattice structure

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20140 Geomechanical Numerical Modeling of Well Wall in Drilling with Finite Difference Method

Authors: Marzieh Zarei

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Well instability is one of the most fundamental challenges faced by the oil and gas industry. Well wall stability analysis is a gap to be filled in the oil industry. The collection of static data such as well logging leads to the construction of a geomechanical numerical model, which will help in assessing the probable risks in future drilling. In this paper, geomechanical model was designed, and mechanical properties of the rock was determined at all points of the model. It was found the safe mud window was determined and the minimum and maximum mud pressures were determined in the ranges of 70-60 MPa and 110-100 MPa, respectively.

Keywords: geomechanics, numerical model, well stability, in-situ stress, underbalanced drilling

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20139 Spatial Design Transformation of Mount Merapi's Dwellings Using Diachronic Approach

Authors: Catharina Dwi Astuti Depari, Gregorius Agung Setyonugroho

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In concern for human safety, living in disaster-prone areas is twofold: it is profoundly cataclysmic yet perceptibly contributive. This paradox could be identified in Kalitengah Lor Sub-village community who inhabit Mount Merapi’s most hazardous area, putting them to the highest exposure to eruptions’ cataclysmic impacts. After the devastating incident in 2010, through the Action Plan for Rehabilitation and Reconstruction, the National Government with immediate aid from humanitarian agencies initiated a relocation program by establishing nearly 2,613 temporary shelters throughout the mountain’s region. The problem arose as some of the most affected communities including those in Kalitengah Lor Sub-village, persistently refused to relocate. The obnoxious experience of those living in temporary shelters resulted from the program’s failure to support a long-term living was assumed to instigate the rejection. From the psychological standpoint, this phenomenon reflects the emotional bond between the affected communities with their former dwellings. Regarding this, the paper aims to reveal the factors influencing the emotional attachment of Kalitengah Lor community to their former dwellings including the dwellings’ spatial design transformation prior and post the eruption in 2010. The research adopted Likert five scale-questionnaire comprising a wide range of responses from strongly agree to strongly disagree. The responses were then statistically measured, leading to consensus that provides bases for further interpretations toward the local’s characteristics. Using purposive unit sampling technique, 50 respondents from 217 local households were randomly selected. Questions in the questionnaire were developed with concerns on the aspects of place attachment concept: affection, cognitive, behavior, and perception. Combined with quantitative method, the research adopted diachronic method which was aimed to analyze the spatial design transformation of each dwelling in relation to the inhabitant’s daily activities and personal preferences. The research found that access to natural resources like sand mining, agricultural farms and wood forests, social relationship and physical proximity from house to personal asset like cattle shed, are the dominant factors encouraging the locals to emotionally attached to their former dwellings. Consequently, each dwelling’s spatial design is suffered from changes in which the current house is typically larger in dimension and the bathroom is replaced by public toilet located outside the house’s backyard. Relatively unchanged, the cattle shed is still located in front of the house, the continuous visual relationship, particularly between the living and family room, is maintained, as well as the main orientation of the house towards the local street.

Keywords: diachronic method, former dwellings, local’s characteristics, place attachment, spatial design transformation

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20138 Study of the Protection of Induction Motors

Authors: Bencheikh Abdellah

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In this paper, we present a mathematical model dedicated to the simulation breaks bars in a three-phase cage induction motor. This model is based on a mesh circuit representing the rotor cage. The tested simulation allowed us to demonstrate the effectiveness of this model to describe the behavior of the machine in a healthy state, failure.

Keywords: AC motors, squirrel cage, diagnostics, MATLAB, SIMULINK

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20137 Dynamic Model of Heterogeneous Markets with Imperfect Information for the Optimization of Company's Long-Time Strategy

Authors: Oleg Oborin

Abstract:

This paper is dedicated to the development of the model, which can be used to evaluate the effectiveness of long-term corporate strategies and identify the best strategies. The theoretical model of the relatively homogenous product market (such as iron and steel industry, mobile services or road transport) has been developed. In the model, the market consists of a large number of companies with different internal characteristics and objectives. The companies can perform mergers and acquisitions in order to increase their market share. The model allows the simulation of long-time dynamics of the market (for a period longer than 20 years). Therefore, a large number of simulations on random input data was conducted in the framework of the model. After that, the results of the model were compared with the dynamics of real markets, such as the US steel industry from the beginning of the XX century to the present day, and the market of mobile services in Germany for the period between 1990 and 2015.

Keywords: Economic Modelling, Long-Time Strategy, Mergers and Acquisitions, Simulation

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20136 Life Prediction Method of Lithium-Ion Battery Based on Grey Support Vector Machines

Authors: Xiaogang Li, Jieqiong Miao

Abstract:

As for the problem of the grey forecasting model prediction accuracy is low, an improved grey prediction model is put forward. Firstly, use trigonometric function transform the original data sequence in order to improve the smoothness of data , this model called SGM( smoothness of grey prediction model), then combine the improved grey model with support vector machine , and put forward the grey support vector machine model (SGM - SVM).Before the establishment of the model, we use trigonometric functions and accumulation generation operation preprocessing data in order to enhance the smoothness of the data and weaken the randomness of the data, then use support vector machine (SVM) to establish a prediction model for pre-processed data and select model parameters using genetic algorithms to obtain the optimum value of the global search. Finally, restore data through the "regressive generate" operation to get forecasting data. In order to prove that the SGM-SVM model is superior to other models, we select the battery life data from calce. The presented model is used to predict life of battery and the predicted result was compared with that of grey model and support vector machines.For a more intuitive comparison of the three models, this paper presents root mean square error of this three different models .The results show that the effect of grey support vector machine (SGM-SVM) to predict life is optimal, and the root mean square error is only 3.18%. Keywords: grey forecasting model, trigonometric function, support vector machine, genetic algorithms, root mean square error

Keywords: Grey prediction model, trigonometric functions, support vector machines, genetic algorithms, root mean square error

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20135 Cultural Boundaries and Mental Health Stigma: A Systemic Review of Interventions to Reduce Opposition of Mental Health Services in Asian American Families

Authors: Tanya L. Patimeteeporn, Murali D. Nair

Abstract:

There is a wide range of literature that suggests the factors that prevent Asian American families from utilizing mental health services. These factors arise from a combination of cultural perceptions of mental illness, and methods of treating them without the use of a mental health professional. Due to the increased awareness of Asian Americans’ stigmatization to mental health, there has been an effort to create culturally competent interventions for Asian American families that would reduce opposition to mental health services. Assessment of the effectiveness of these interventions reveals practices that integrate traditional healing methods with psychoeducation are more likely to promote receptiveness of mental health services by Asian American families. The documentary in this review, demonstrates these traditional healing methods from various ethnic enclaves in Los Angeles. In addition, mental health professionals who provide these interventions to Asian American families need to consider culture-bound syndromes and the various Asian health philosophies and belief systems in order to provide a culturally sensitive holistic treatment for their clients. However, because the literature on these interventions is limited, there is a need for a larger body of evidence to accurately assess the effectiveness of these culturally competent psychoeducation interventions.

Keywords: Asian American, cultural boundaries, intervention, mental health stigma, psychoeducation, traditional healing

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20134 Expounding the Evolution of the Proto-Femme Fatale and Its Correlation with the New Woman: A Close Study of David Mamet's Oleanna

Authors: Silvia Elias

Abstract:

The 'Femme Fatale' figure has become synonymous with a mysterious and seductive woman whose charms captivate her lovers into bonds of irresistible desire, often leading them to compromise or downfall. Originally, a Femme Fatale typically uses her beauty to lead men to their destruction but in modern literature, she represents a direct attack on traditional womanhood and the nuclear family as she refuses to abide by the pillars of mainstream society creating an image of a strong independent woman who defies the control of men and rejects the institution of the family. This research aims at discussing the differences and similarities between the femme fatale and the New Woman and how they are perceived by the audience. There is often confusion between the characteristics that define a New Woman and a Femme Fatale since both women desire independence, challenge typical gender role casting, push against the limits of the patriarchal society and take control of their sexuality. The study of the femme fatale remains appealing in modern times because the fear of gender equality gives life to modern femme fatale versions and post-modern literary works introduce their readers to new versions of the deadly seductress. One that does not fully depend on her looks to destroy men. The idea behind writing this paper was born from reading David Mamet's two-character play Oleanna (1992) and tracing the main female protagonist/antagonist's transformation from a helpless inarticulate girl into a powerful controlling negotiator who knows how to lead a bargain and maintain the upper hand.

Keywords: Circe, David, Eve, evolution, feminist, femme fatale, gender, Mamet, new, Odysseus, Oleanna, power, Salome, schema, seduction, temptress, woman

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20133 Modelling Export Dynamics in the CSEE Countries Using GVAR Model

Authors: S. Jakšić, B. Žmuk

Abstract:

The paper investigates the key factors of export dynamics for a set of Central and Southeast European (CSEE) countries in the context of current economic and financial crisis. In order to model the export dynamics a Global Vector Auto Regressive (GVAR) model is defined. As opposed to models which model each country separately, the GVAR combines all country models in a global model which enables obtaining important information on spill-over effects in the context of globalization and rising international linkages. The results of the study indicate that for most of the CSEE countries, exports are mainly driven by domestic shocks, both in the short run and in the long run. This study is the first application of the GVAR model to studying the export dynamics in the CSEE countries and therefore the results of the study present an important empirical contribution.

Keywords: export, GFEVD, global VAR, international trade, weak exogeneity

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20132 Documentary Filmmaking as Activism: Case Studies in Advocacy and Social Justice

Authors: Babatunde Kolawole

Abstract:

This paper embarks on an exploration of the compelling interplay between documentary filmmaking and activism, delving into their symbiotic relationship and profound impact on advocacy and social justice causes. Through an in-depth analysis of diverse case studies, it seeks to illuminate the instances where documentary films have emerged as potent tools for effecting social change and advancing the principles of justice. This research underscores the vital role played by documentary filmmakers in harnessing the medium's unique capacity to engage, educate, and mobilize audiences while advocating for societal transformation. The primary focus of this study is on a selection of compelling case studies spanning various topics and causes, each exemplifying the marriage between documentary filmmaking and activism. These case studies encompass a broad spectrum of subjects, from environmental conservation and climate change to civil rights movements and human rights struggles. By examining these real-world instances, this paper endeavors to provide a comprehensive understanding of the strategies, challenges, and ethical considerations that underpin the practice of documentary filmmaking as a form of activism. Throughout the paper, it becomes evident that the potency of documentary filmmaking lies in its ability to blend artistry with social impact. The selected case studies vividly demonstrate how documentary filmmakers, armed with cameras and a passion for change, have emerged as critical agents of societal transformation. Whether it be exposing environmental atrocities, shedding light on systemic inequalities, or giving voice to marginalized communities, these documentaries have played a pivotal role in pushing the boundaries of advocacy and social justice. One of the key themes explored in this paper is the evolving nature of documentary filmmaking as a tool for activism. It delves into the shift from traditional observational documentaries to more participatory and immersive approaches, highlighting the dynamic ways in which filmmakers engage with their subjects and audiences. This evolution is exemplified in case studies where filmmakers have collaborated with the communities they document, fostering a sense of agency and empowerment among those whose stories are being told. Furthermore, this research underscores the ethical considerations inherent in the intersection of documentary filmmaking and activism. It scrutinizes questions surrounding representation, objectivity, and the responsibility of filmmakers in portraying complex social issues. By dissecting ethical dilemmas faced by documentary filmmakers in these case studies, this paper encourages a critical examination of the ethical boundaries and obligations in the realm of advocacy-driven filmmaking. In conclusion, this paper aims to shed light on the remarkable potential of documentary filmmaking as a catalyst for activism and social justice. Through the lens of compelling case studies, it illustrates the transformative power of the medium in effecting change, amplifying underrepresented voices, and mobilizing global audiences. It is hoped that this research will not only inform the discourse on documentary activism but also inspire filmmakers, scholars, and advocates to continue leveraging the cinematic art form as a formidable force for a more just and equitable world.

Keywords: film, filmmaker, documentary, human right

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20131 Simplified 3R2C Building Thermal Network Model: A Case Study

Authors: S. M. Mahbobur Rahman

Abstract:

Whole building energy simulation models are widely used for predicting future energy consumption, performance diagnosis and optimum control.  Black box building energy modeling approach has been heavily studied in the past decade. The thermal response of a building can also be modeled using a network of interconnected resistors (R) and capacitors (C) at each node called R-C network. In this study, a model building, Case 600, as described in the “Standard Method of Test for the Evaluation of Building Energy Analysis Computer Program”, ASHRAE standard 140, is studied along with a 3R2C thermal network model and the ASHRAE clear sky solar radiation model. Although building an energy model involves two important parts of building component i.e., the envelope and internal mass, the effect of building internal mass is not considered in this study. All the characteristic parameters of the building envelope are evaluated as on Case 600. Finally, monthly building energy consumption from the thermal network model is compared with a simple-box energy model within reasonable accuracy. From the results, 0.6-9.4% variation of monthly energy consumption is observed because of the south-facing windows.

Keywords: ASHRAE case study, clear sky solar radiation model, energy modeling, thermal network model

Procedia PDF Downloads 124
20130 The Onset of Ironing during Casing Expansion

Authors: W. Assaad, D. Wilmink, H. R. Pasaribu, H. J. M. Geijselaers

Abstract:

Shell has developed a mono-diameter well concept for oil and gas wells as opposed to the traditional telescopic well design. A Mono-diameter well design allows well to have a single inner diameter from the surface all the way down to reservoir to increase production capacity, reduce material cost and reduce environmental footprint. This is achieved by expansion of liners (casing string) concerned using an expansion tool (e.g. a cone). Since the well is drilled in stages and liners are inserted to support the borehole, overlap sections between consecutive liners exist which should be expanded. At overlap, the previously inserted casing which can be expanded or unexpanded is called the host casing and the newly inserted casing is called the expandable casing. When the cone enters the overlap section, an expandable casing is expanded against a host casing, a cured cement layer and formation. In overlap expansion, ironing or lengthening may appear instead of shortening in the expandable casing when the pressure exerted by the host casing, cured cement layer and formation exceeds a certain limit. This pressure is related to cement strength, thickness of cement layer, host casing material mechanical properties, host casing thickness, formation type and formation strength. Ironing can cause implications that hinder the deployment of the technology. Therefore, the understanding of ironing becomes essential. A physical model is built in-house to calculate expansion forces, stresses, strains and post expansion casing dimensions under different conditions. In this study, only free casing and overlap expansion of two casings are addressed while the cement and formation will be incorporated in future study. Since the axial strain can be predicted by the physical model, the onset of ironing can be confirmed. In addition, this model helps in understanding ironing and the parameters influencing it. Finally, the physical model is validated with Finite Element (FE) simulations and small-scale experiments. The results of the study confirm that high pressure leads to ironing when the casing is expanded in tension mode.

Keywords: casing expansion, cement, formation, metal forming, plasticity, well design

Procedia PDF Downloads 164