Search results for: space frame chassis
Commenced in January 2007
Frequency: Monthly
Edition: International
Paper Count: 4542

Search results for: space frame chassis

4152 Investigation of the Effects of Sampling Frequency on the THD of 3-Phase Inverters Using Space Vector Modulation

Authors: Khattab Al Qaisi, Nicholas Bowring

Abstract:

This paper presents the simulation results of the effects of sampling frequency on the total harmonic distortion (THD) of three-phase inverters using the space vector pulse width modulation (SVPWM) and space vector control (SVC) algorithms. The relationship between the variables was studied using curve fitting techniques, and it has been shown that, for 50 Hz inverters, there is an exponential relation between the sampling frequency and THD up to around 8500 Hz, beyond which the performance of the model becomes irregular, and there is an negative exponential relation between the sampling frequency and the marginal improvement to the THD. It has also been found that the performance of SVPWM is better than that of SVC with the same sampling frequency in most frequency range, including the range where the performance of the former is irregular.

Keywords: DSI, SVPWM, THD, DC-AC converter, sampling frequency, performance

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4151 Agent-Based Modeling of Pedestrian Corridor Congestion on the Characteristics of Physical Space Form

Authors: Sun Shi, Sun Cheng

Abstract:

The pedestrian corridor is the most crowded area in the public space. The crowded severity has been focused on the field of evacuation strategies of the entrance in large public spaces. The aim of this paper is to analyze the walking efficiency in different spaces of pedestrian corridor with the variation of spatial parameters. The congestion condition caused by the variation of walking efficiency is modeled as well. This study established the space model of the walking corridor by setting the width, slope, turning form and turning angle of the pedestrian corridor. The pedestrian preference of walking mode varied with the difference of the crowded severity, walking speed, field of vision, sight direction and the expected destination, which is influenced by the characters of physical space form. Swarm software is applied to build Agent model. According to the output of the Agent model, the relationship between the pedestrian corridor width, ground slope, turning forms, turning angle and the walking efficiency, crowded severity is acquired. The results of the simulation can be applied to pedestrian corridor design in order to reduce the crowded severity and the potential safety risks caused by crowded people.

Keywords: crowded severity, multi-agent, pedestrian preference, urban space design

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4150 Costume Portrayal In K. Asif’s Mughal E Azam

Authors: Anketa Kumar, Rajantheran Al Muniandy, Rishabh Kumar

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For centuries, Indian costumes are admired for their great aesthetics, functional and narrative qualities. The purpose of the current study is to investigate the role of costumes as visual narratives in Hindi Cinema as Filmmaking is simply one of the most recent manifestations of the human desire to tell stories in which costume acts as a tool to be read as an Intertext by the viewers watching the films. The problem that promoted this study arose when clothes become an interesting topic when examined within the social structures in which they are worn. It is this visual image of dress worn by the character that is investigated in this research through Hindi Cinema of the 1960s, which was a reflection of the society in the realistic form. This research intends to integrate the application of Roland Barthes Semiotic theory in analyzing main movie characters in the National Award-Winning Hindi movie Mughal e Azam (1960). The research helps in filling the gap between the singular level of interpretation and another level that offers a solution towards bridging the gap in viewers' manifold interpretation of a particular movie product. This study focuses on how visual appearance communicates for building up of perception and can relate to notions of realism, defining cultural identity and status in the society. The research methodology is subjected analytical technique that employs in this research is qualitative and descriptive in nature with the use of the Freeze frame technique. The portrayal of costumes is explained with Barthes' principles of Semiotics. The freeze-frame technique stops the motion of the film on a single frame and allows the chosen image to be read as a still photograph. The finding during this research into costume portrayal in the movie was that freezing the frame in midst of running the films attracted attention towards intricate costume details, leading to record the nuanced observations of this minutiae during the movie. Given that during the application of interpretation while watching K Asif’s Mughal e Azam focused on certain aspects of costumes of the king. On the same idea, further research can be employed to strengthen the relation between costumes and visual narration.

Keywords: character portrayal, costumes, Indian cinema, semiotics, visual significance

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4149 Dynamic Interaction between Two Neighboring Tunnels in a Layered Half-Space

Authors: Chao He, Shunhua Zhou, Peijun Guo

Abstract:

The vast majority of existing underground railway lines consist of twin tunnels. In this paper, the dynamic interaction between two neighboring tunnels in a layered half-space is investigated by an analytical model. The two tunnels are modelled as cylindrical thin shells, while the soil in the form of a layered half-space with two cylindrical cavities is simulated by the elastic continuum theory. The transfer matrix method is first used to derive the relationship between the plane wave vectors in arbitrary layers and the source layer. Thereafter, the wave translation and transformation are introduced to determine the plane and cylindrical wave vectors in the source layer. The solution for the dynamic interaction between twin tunnels in a layered half-space is obtained by means of the compatibility of displacements and equilibrium of stresses on the two tunnel–soil interfaces. By coupling the proposed model with a fully track model, the train-induced vibrations from twin tunnels in a multi-layered half-space are investigated. The numerical results demonstrate that the existence of a neighboring tunnel has a significant effect on ground vibrations.

Keywords: underground railway, twin tunnels, wave translation and transformation, transfer matrix method

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4148 Study on Liquid Nitrogen Gravity Circulation Loop for Cryopumps in Large Space Simulator

Authors: Weiwei Shan, Wenjing Ding, Juan Ning, Chao He, Zijuan Wang

Abstract:

Gravity circulation loop for the cryopumps of the space simulator is introduced, and two phase mathematic model of flow heat transfer is analyzed as well. Based on this model, the liquid nitrogen (LN2) gravity circulation loop including its equipment and layout is designed and has served as LN2 feeding system for cryopumps in one large space simulator. With the help of control software and human machine interface, this system can be operated flexibly, simply, and automatically under four conditions. When running this system, the results show that the cryopumps can be cooled down and maintained under the required temperature, 120 K.

Keywords: cryopumps, gravity circulation loop, liquid nitrogen, two-phase

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4147 Liturgical Elements and Symbolism of Light in Christian Sacred Space

Authors: Zorana Sokol Gojnik, Igor Gojnik, Marina Simunic Bursic

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The light is one of the major themes of theology of sacred space. Christian theology, but also architecture in its complexity, is permeated by the symbolism of light from its beginning. The aim of this paper is to deeply analyse the symbolism of light in every single element of contemporary Christian sacred space such as altar, ambo, baptistery, tabernacle, confessionals, stations of the cross, etc. The research will be carried out using the methodology of research of literature and comparatively observation of contemporary examples of sacred architecture. The research will use the insights of analyzed literature and examples of sacred architecture in order to describe the background of the problem as well as to complement the received results with the reliable scientific findings. The paper will highlight the importance of symbolic and theological points of view in contemporary church design using the light as a building part of every single part of sacred architecture as there is an insight that, in contemporary sacred architecture, there is a lack of understanding of symbolic and theological aspect of light while designing new sacred spaces.

Keywords: architecture, liturgy, sacred architecture, theology of space

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4146 The Effect of Masonry Infills on the Seismic Response of Reinforced Concrete Structures

Authors: Mohammad Reza Ameri, Ali Massumi, Behnam Mahboubi

Abstract:

The performance of masonry infilled frames during the past earthquakes shows that the infill panels play a major role as earthquake-resistant elements. The present study examines the influence of infill panels on seismic behavior of RC frame structures. For this purpose, several low- and mid-rise RC frames (two-, four-, seven-, and ten story) were numerically investigated. Reinforced masonry infill panels were then placed within the frames and the models were subjected to several nonlinear incremental static and dynamic analyses. The results of analyses showed that the use of reinforced masonry infill panels in RC frame structures can have beneficial effects on structural performance. It was confirmed that the use of masonry infill panels results in an increment in strength and stiffness of the framed buildings, followed by a reduction in displacement demand for the structural systems.

Keywords: reinforced masonry infill panels, nonlinear static analysis, incremental dynamic analysis, low-rise reinforced concrete frames, mid-rise reinforced concrete frames

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4145 Secured Transmission and Reserving Space in Images Before Encryption to Embed Data

Authors: G. R. Navaneesh, E. Nagarajan, C. H. Rajam Raju

Abstract:

Nowadays the multimedia data are used to store some secure information. All previous methods allocate a space in image for data embedding purpose after encryption. In this paper, we propose a novel method by reserving space in image with a boundary surrounded before encryption with a traditional RDH algorithm, which makes it easy for the data hider to reversibly embed data in the encrypted images. The proposed method can achieve real time performance, that is, data extraction and image recovery are free of any error. A secure transmission process is also discussed in this paper, which improves the efficiency by ten times compared to other processes as discussed.

Keywords: secure communication, reserving room before encryption, least significant bits, image encryption, reversible data hiding

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4144 Design of Quality Assessment System for On-Orbit 3D Printing Based on 3D Reconstruction Technology

Authors: Jianning Tang, Trevor Hocksun Kwan, Xiaofeng Wu

Abstract:

With the increasing demand for space use in multiple sectors (navigation, telecommunication, imagery, etc.), the deployment and maintenance demand of satellites are growing. Considering the high launching cost and the restrictions on weight and size of the payload when using launch vehicle, the technique of on-orbit manufacturing has obtained more attention because of its significant potential to support future space missions. 3D printing is the most promising manufacturing technology that could be applied in space. However, due to the lack of autonomous quality assessment, the operation of conventional 3D printers still relies on human presence to supervise the printing process. This paper is proposed to develop an automatic 3D reconstruction system aiming at detecting failures on the 3D printed objects through application of point cloud technology. Based on the data obtained from the point cloud, the 3D printer could locate the failure and repair the failure. The system will increase automation and provide 3D printing with more feasibilities for space use without human interference.

Keywords: 3D printing, quality assessment, point cloud, on-orbit manufacturing

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4143 Saudi and U.S. Newspaper Coverage of Saudi Vision 2030 Concerning Women in Online Newspapers

Authors: Ziyad Alghamdi

Abstract:

This research investigates how issues concerning Saudi women have been represented in selected U.S. and Saudi publications. Saudi Vision 2030 is the Kingdom of Saudi Arabia's development strategy, which was revealed on April 25, 2016. This study used 115 news items across selected newspapers as its sampling. The New York Times and the Washington Post were chosen to represent U.S. newspapers and picked two Saudi newspapers, Al Jazirah, and Al Watan. This research examines how these issues were covered before and during the implementation of Saudi Vision 2030. The news pieces were analyzed using both quantitative and qualitative methodologies. The qualitative study employed an inductive technique to uncover frames. Furthermore, this work looked at how American and Saudi publications had framed Saudi women depicted in images by reviewing the photographs used in news reports about Saudi women's issues. The primary conclusion implies that the human-interest frame was more prevalent in American media, whereas the economic frame was more prevalent in Saudi publications. A variety of diverse topics were considered.

Keywords: Saudi newspapers, Saudi Vision 2030, framing theory, Saudi women

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4142 Sustainability in Space: Material Efficiency in Space Missions

Authors: Hamda M. Al-Ali

Abstract:

From addressing fundamental questions about the history of the solar system to exploring other planets for any signs of life have always been the core of human space exploration. This triggered humans to explore whether other planets such as Mars could support human life on them. Therefore, many planned space missions to other planets have been designed and conducted to examine the feasibility of human survival on them. However, space missions are expensive and consume a large number of various resources to be successful. To overcome these problems, material efficiency shall be maximized through the use of reusable launch vehicles (RLV) rather than disposable and expendable ones. Material efficiency is defined as a way to achieve service requirements using fewer materials to reduce CO2 emissions from industrial processes. Materials such as aluminum-lithium alloys, steel, Kevlar, and reinforced carbon-carbon composites used in the manufacturing of spacecrafts could be reused in closed-loop cycles directly or by adding a protective coat. Material efficiency is a fundamental principle of a circular economy. The circular economy aims to cutback waste and reduce pollution through maximizing material efficiency so that businesses can succeed and endure. Five strategies have been proposed to improve material efficiency in the space industry, which includes waste minimization, introduce Key Performance Indicators (KPIs) to measure material efficiency, and introduce policies and legislations to improve material efficiency in the space sector. Another strategy to boost material efficiency is through maximizing resource and energy efficiency through material reusability. Furthermore, the environmental effects associated with the rapid growth in the number of space missions include black carbon emissions that lead to climate change. The levels of emissions must be tracked and tackled to ensure the safe utilization of space in the future. The aim of this research paper is to examine and suggest effective methods used to improve material efficiency in space missions so that space and Earth become more environmentally and economically sustainable. The objectives used to fulfill this aim are to identify the materials used in space missions that are suitable to be reused in closed-loop cycles considering material efficiency indicators and circular economy concepts. An explanation of how spacecraft materials could be re-used as well as propose strategies to maximize material efficiency in order to make RLVs possible so that access to space becomes affordable and reliable is provided. Also, the economic viability of the RLVs is examined to show the extent to which the use of RLVs has on the reduction of space mission costs. The environmental and economic implications of the increase in the number of space missions as a result of the use of RLVs are also discussed. These research questions are studied through detailed critical analysis of the literature, such as published reports, books, scientific articles, and journals. A combination of keywords such as material efficiency, circular economy, RLVs, and spacecraft materials were used to search for appropriate literature.

Keywords: access to space, circular economy, material efficiency, reusable launch vehicles, spacecraft materials

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4141 Strong Convergence of an Iterative Sequence in Real Banach Spaces with Kadec Klee Property

Authors: Umar Yusuf Batsari

Abstract:

Let E be a uniformly smooth and uniformly convex real Banach space and C be a nonempty, closed and convex subset of E. Let $V= \{S_i : C\to C, ~i=1, 2, 3\cdots N\}$ be a convex set of relatively nonexpansive mappings containing identity. In this paper, an iterative sequence obtained from CQ algorithm was shown to have strongly converge to a point $\hat{x}$ which is a common fixed point of relatively nonexpansive mappings in V and also solve the system of equilibrium problems in E. The result improve some existing results in the literature.

Keywords: relatively nonexpansive mappings, strong convergence, equilibrium problems, uniformly smooth space, uniformly convex space, convex set, kadec klee property

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4140 Dimensions of Public Spaces: Feelings through Human Senses

Authors: Piyush Hajela

Abstract:

The significance of public spaces is on a rise in Indian cities as a strong interaction space across cultures and community. It is a pertinent gathering space for people across age and gender, where the face keeps changing with time. A public space is directly related to the social dimension, people, comfort, safety, and security, that, it proposes to provide, as inherent qualities. The presence of these and other dimensions of space, together with related equitable environments, impart certain quality to a public space. The higher the optimum contents of these dimensions, the better the quality of public space. Public is represented by PEOPLE through society and community, and space is created by dimensions. Society contains children, women and the elderly, community is composed of social, and religious groups. These behave differently in a different setting and call for varied quality of spaces, created and generated. Public spaces are spread across a city and have more or less established their existence and prominence in a social set up. While few of them are created others are discovered by the people themselves in their constant search for desirable interactive public spaces. These are the most sought after gathering spaces that have the quality of promoting social interaction, providing free accessibility, provide desirable scale etc. The emergence of public space dates back to the times when people started forming communities, display cultures and traditions publicly, gathered for religious observations and celebrations, and address the society. Traditional cities and societies in India were feudal and orthodox in their nature and yet had public spaces. When the gathering of people at one point in a city became more frequent the point became more accessible and occupied. Baras (large courts, Chowks (public squares) and Maidans (large grounds) became well-known gathering spaces in the towns and cities. As the population grew such points grew in number, each becoming a public space in itself and with a different and definite social character. The author aims at studying the various dimensions of public spaces with which a public space has power to hold people for a significant period of time. The human senses here are note referred to as taste, sight, hearing, touch or smell, but how human senses collectively respond to when stationed in a given public space. The collectives may reflect in dimensions like comfort, safety, environment, freedom etc. Various levels of similar other responses would be studied through interviews, observations and other scientific methods for both qualitative and quantitative analysis.

Keywords: society, interaction, people, accessibility, comfort, enclosure

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4139 Numerical Tools for Designing Multilayer Viscoelastic Damping Devices

Authors: Mohammed Saleh Rezk, Reza Kashani

Abstract:

Auxiliary damping has gained popularity in recent years, especially in structures such as mid- and high-rise buildings. Distributed damping systems (typically viscous and viscoelastic) or reactive damping systems (such as tuned mass dampers) are the two types of damping choices for such structures. Distributed VE dampers are normally configured as braces or damping panels, which are engaged through relatively small movements between the structural members when the structure sways under wind or earthquake loading. In addition to being used as stand-alone dampers in distributed damping applications, VE dampers can also be incorporated into the suspension element of tuned mass dampers (TMDs). In this study, analytical and numerical tools for modeling and design of multilayer viscoelastic damping devices to be used in dampening the vibration of large structures are developed. Considering the limitations of analytical models for the synthesis and analysis of realistic, large, multilayer VE dampers, the emphasis of the study has been on numerical modeling using the finite element method. To verify the finite element models, a two-layer VE damper using ½ inch synthetic viscoelastic urethane polymer was built, tested, and the measured parameters were compared with the numerically predicted ones. The numerical model prediction and experimentally evaluated damping and stiffness of the test VE damper were in very good agreement. The effectiveness of VE dampers in adding auxiliary damping to larger structures is numerically demonstrated by chevron bracing one such damper numerically into the model of a massive frame subject to an abrupt lateral load. A comparison of the responses of the frame to the aforementioned load, without and with the VE damper, clearly shows the efficacy of the damper in lowering the extent of frame vibration.

Keywords: viscoelastic, damper, distributed damping, tuned mass damper

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4138 Towards the Effectiveness/ Performance of Spatial Communication within the Composite Interior Spaces: Wayfinding System in the Saudi National Museum as a Case Study

Authors: Afnan T. Bagasi, Donia M. Bettaieb, Abeer Alsobahi

Abstract:

The wayfinding system is related to the course of the museum journey for visitors directly and indirectly. The design aspects of this system play an important role, making it an effective and communication system within the museum space. However, translating the concepts that pertain to its design, such as Intelligibility that is based on integration and connectivity in museum space design, needs more customization in the form of specific design considerations with reference to the most important approaches. Those approaches link the organizational and practical aspects to the semiotic and semantic aspects related to the space syntax by targeting the visual and perceived consistency of visitors. In this context, the study aims to identify how to apply the concept of intelligibility and clarity by employing integration and connectivity to design a wayfinding system in museums as a kind of composite interior space. Using the available plans and images to extrapolate the design considerations used to design the wayfinding system in the Saudi National Museum as a case study, a descriptive-analytical method was used to understand the basic organizational and morphological principles of the museum space through four main aspects in space design: morphological, semantic, semiotic, and pragmatic. The study's findings will assist designers, professionals, and researchers in the field of museum design in understanding the significance of the wayfinding system by delving into it through museum spaces by highlighting the essential aspects using a clear analytical method.

Keywords: wayfinding system, museum journey, intelligibility, integration, connectivity

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4137 Hip and Valley Support Location in Wood Framing

Authors: P. Hajyalikhani, B. Hudson, D. Boll, L. Boren, Z. Sparks, M. Ward

Abstract:

Wood Light frame construction is one of the most common types of construction methods for residential and light commercial building in North America and parts of Europe. The typical roof framing for wood framed building is sloped and consists of several structural members such as rafters, hips, and valleys which are connected to the ridge and ceiling joists. The common slopes for roofs are 3/12, 8/12, and 12/12. Wood framed residential roof failure is most commonly caused by wind damage in such buildings. In the recent study, one of the weaknesses of wood framed roofs is long unsupported structural member lengths, such as hips and valleys. The purpose of this research is to find the critical support location for long hips and valleys with different slopes. ForteWeb software is used to find the critical location. The analysis results demonstrating the maximum unbraced hip and valley length are from 8.5 to 10.25 ft. dependent on the slope and roof type.

Keywords: wood frame, stick framing, hip, valley

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4136 Stronger Together – Micro-Entrepreneurs’ Resilience Development in a Communal Training Space 

Authors: Halonen

Abstract:

Covid-19 pandemic and the succeeding crises have profoundly shaken the accustomed ways of interaction and thereby challenged the customary engagement patterns among entrepreneurs Consequently, this has led to the experience of lack of collegial interaction for some. Networks and relationships are a crucial factor to strengthening resilience, being especially significant in non-ordinary times. This study aims to shed light on entrepreneurs’ resilience development in and through entrepreneurs’ communal and training space. The context for research is a communal training space in a municipality in Finland of which goal is to help entrepreneurs to experience of peer support and community as part of the "tribe" is strengthened, the entrepreneurs' well-being at work, resilience, ability to change, innovativeness and general life management is strengthened. This communal space is regarded as an example of a physical community of practice (CoP) of entrepreneurs. The research aims to highlight the importance of rediscovering the “new normal” communality as itself but as a key building block of resilience. The initial research questions of the study are: RQ1: What is the role of entrepreneurs’ CoP and communal space in nurturing resilience development among them? RQ2: What positive entrepreneurial outcomes can be achieved through established CoP. The data will be gathered starting from the launch of the communality space in September 2023 onwards. It includes participatory observations of training gatherings, interviews with entrepreneurs and utilizes action research as the method. The author has an active role in participating and facilitating the development. The full paper will be finalized by the fall 2024. The idea of the new normal communality in a CoP among entrepreneurs is to be rediscovered due to its positive impact on entrepreneur’s resilience and business success. The other implications of study can extend to wider entrepreneurial ecosystem and other key stakeholders. Especially emphasizing the potential of communality in CoP for fostering entrepreneurs’ resilience and well-being ensuing business growth, community-driven entrepreneurship development and vitality of the case municipality.

Keywords: resilience, resilience development, communal space, community of practice (CoP)

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4135 A Four-Step Ortho-Rectification Procedure for Geo-Referencing Video Streams from a Low-Cost UAV

Authors: B. O. Olawale, C. R. Chatwin, R. C. D. Young, P. M. Birch, F. O. Faithpraise, A. O. Olukiran

Abstract:

Ortho-rectification is the process of geometrically correcting an aerial image such that the scale is uniform. The ortho-image formed from the process is corrected for lens distortion, topographic relief, and camera tilt. This can be used to measure true distances, because it is an accurate representation of the Earth’s surface. Ortho-rectification and geo-referencing are essential to pin point the exact location of targets in video imagery acquired at the UAV platform. This can only be achieved by comparing such video imagery with an existing digital map. However, it is only when the image is ortho-rectified with the same co-ordinate system as an existing map that such a comparison is possible. The video image sequences from the UAV platform must be geo-registered, that is, each video frame must carry the necessary camera information before performing the ortho-rectification process. Each rectified image frame can then be mosaicked together to form a seamless image map covering the selected area. This can then be used for comparison with an existing map for geo-referencing. In this paper, we present a four-step ortho-rectification procedure for real-time geo-referencing of video data from a low-cost UAV equipped with multi-sensor system. The basic procedures for the real-time ortho-rectification are: (1) Decompilation of video stream into individual frames; (2) Finding of interior camera orientation parameters; (3) Finding the relative exterior orientation parameters for each video frames with respect to each other; (4) Finding the absolute exterior orientation parameters, using self-calibration adjustment with the aid of a mathematical model. Each ortho-rectified video frame is then mosaicked together to produce a 2-D planimetric mapping, which can be compared with a well referenced existing digital map for the purpose of georeferencing and aerial surveillance. A test field located in Abuja, Nigeria was used for testing our method. Fifteen minutes video and telemetry data were collected using the UAV and the data collected were processed using the four-step ortho-rectification procedure. The results demonstrated that the geometric measurement of the control field from ortho-images are more reliable than those from original perspective photographs when used to pin point the exact location of targets on the video imagery acquired by the UAV. The 2-D planimetric accuracy when compared with the 6 control points measured by a GPS receiver is between 3 to 5 meters.

Keywords: geo-referencing, ortho-rectification, video frame, self-calibration

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4134 Three-Dimensional Numerical Model of an Earth Air Heat Exchanger under a Constrained Urban Environment in India: Modeling and Validation

Authors: V. Rangarajan, Priyanka Kaushal

Abstract:

This study investigates the effectiveness of a typical Earth Air Heat Exchanger (EATHE) for energy efficient space cooling in an urban environment typified by space and soil-related constraints that preclude an optimal design. It involves the development of a three-dimensional numerical transient model that is validated by measurements at a live site in India. It is found that the model accurately predicts the soil temperatures at various depths as well as the EATHE outlet air temperature. The study shows that such an EATHE, even when designed under constraints, does provide effective space cooling especially during the hot months of the year.

Keywords: earth air heat exchanger (EATHE), India, MATLAB, model, simulation

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4133 Viability of Slab Sliding System for Single Story Structure

Authors: C. Iihoshi, G. A. MacRae, G. W. Rodgers, J. G. Chase

Abstract:

Slab Sliding System (SSS) with Coulomb friction interface between slab and supporting frame is a passive structural vibration control technology. The system can significantly reduce the slab acceleration and accompanied lateral force of the frame. At the same time it is expected to cause the slab displacement magnification by sliding movement. To obtain the general comprehensive seismic response of a single story structure, inelastic response spectra were computed for a large ensemble of ground motions and a practical range of structural periods and friction coefficient values. It was shown that long period structures have no trade-off relation between force reduction and displacement magnification with respect to elastic response, unlike short period structures. For structures with the majority of mass in the slab, the displacement magnification value can be predicted according to simple inelastic displacement relation for in elastically responding SDOF structures because the system behaves elastically to a SDOF structure.

Keywords: earthquake, isolation, slab, sliding

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4132 Optimal Seismic Design of Reinforced Concrete Shear Wall-Frame Structure

Authors: H. Nikzad, S. Yoshitomi

Abstract:

In this paper, the optimal seismic design of reinforced concrete shear wall-frame building structures was done using structural optimization. The optimal section sizes were generated through structural optimization based on linear static analysis conforming to American Concrete Institute building design code (ACI 318-14). An analytical procedure was followed to validate the accuracy of the proposed method by comparing stresses on structural members through output files of MATLAB and ETABS. In order to consider the difference of stresses in structural elements by ETABS and MATLAB, and to avoid over-stress members by ETABS, a stress constraint ratio of MATLAB to ETABS was modified and introduced for the most critical load combinations and structural members. Moreover, seismic design of the structure was done following the International Building Code (IBC 2012), American Concrete Institute Building Code (ACI 318-14) and American Society of Civil Engineering (ASCE 7-10) standards. Typical reinforcement requirements for the structural wall, beam and column were discussed and presented using ETABS structural analysis software. The placement and detailing of reinforcement of structural members were also explained and discussed. The outcomes of this study show that the modification of section sizes play a vital role in finding an optimal combination of practical section sizes. In contrast, the optimization problem with size constraints has a higher cost than that of without size constraints. Moreover, the comparison of optimization problem with that of ETABS program shown to be satisfactory and governed ACI 318-14 building design code criteria.

Keywords: structural optimization, seismic design, linear static analysis, etabs, matlab, rc shear wall-frame structures

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4131 Nation Branding as Reframing: From the Perspective of Translation Studies

Authors: Ye Tian

Abstract:

Soft power has replaced hard power and become one of the most attractive ways nations pursue to expand their international influence. One of the ways to improve a nation’s soft power is to commercialise the country and brand or rebrand it to the international audience, and thus attract interests or foreign investments. In this process, translation has often been regarded as merely a tool, and researches in it are either in translating literature as culture export or in how (in)accuracy of translation influences the branding campaign. This paper proposes to analyse nation branding campaign with framing theory, and thus gives an entry for translation studies to come to a central stage in today’s soft power research. To frame information or elements of a text, an event, or, as in this paper, a nation is to put them in a mental structure. This structure can be built by outsiders or by those who create the text, the event, or by citizens of the nation. To frame information like this can be regarded as a process of translation, as what translation does in its traditional meaning of ‘translating a text’ is to put a framework on the text to, deliberately or not, highlight some of the elements while hiding the others. In the discourse of nations, then, people unavoidably simplify a national image and put the nation into their imaginary framework. In this way, problems like stereotype and prejudice come into being. Meanwhile, if nations seek ways to frame or reframe themselves, they make efforts to have in control what and who they are in the eyes of international audiences, and thus make profits, economically or politically, from it. The paper takes African nations, which are usually perceived as a whole, and the United Kingdom as examples to justify passive and active framing process, and assesses both positive and negative influence framing has on nations. In conclusion, translation as framing causes problems like prejudice, and the image of a nation is not always in the hands of nation branders, but reframing the nation in a positive way has the potential to turn the tide.

Keywords: framing, nation branding, stereotype, translation

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4130 Practicing Spectacular Urbanism in China: Mega-Events, the City of the Spectacle, and Spatialization of State Power

Authors: George Lin

Abstract:

This study examines a practice in which Chinese municipal governments actively pursue momentary and spectacular urbanism through the hosting of mega-events as an instrument to reproduce urban space for the enhancement of place competitiveness and advancement of political career. Practicing event-driven spectacular urbanism is found to have a short-term impact upon the economy and an effect upon the career advancement of the party secretary more than the mayor. Hosting mega-events has been used as a means to create “a harmonious society” and unified social space whereby grievance and discontents are grossed over, ignored, excluded and marginalized. Geographically, a new urban space has been created for the central city to reassert/consolidate its leading competitive position in the regional and national economy at the expense of the disadvantaged and marginalized. Findings of this research call for a critical re-evaluation of the sophisticated state-space inter-relations in the ongoing processes of planetary urbanization and global urban revolution in which China has taken an important part.

Keywords: Chinese cities, mega events, urbanism, urbanization

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4129 Gravity Due to the Expansion of Matter and Distortion of Hyperspace

Authors: Arif Ali, Divya Raj Sapkota

Abstract:

In this paper, we explain gravitational attraction as the consequence of the dynamics of four-dimensional bodies and the consequent distortion of space. This approach provides an alternative direction to understand various physical phenomena based on the existence of the fourth spatial dimension. For this interpretation, we formulate the acceleration due to gravity and orbital velocity based on the accelerating expansion of three-dimensional symmetric bodies. It is also shown how distortion in space caused by the dynamics of four-dimensional bodies counterbalances the effect of expansion. We find that the motion of four-dimensional bodies through four-dimensional space leads to gravitational attraction, and the expansion of bodies leads to surface gravity. Thus, dynamics in the fourth spatial dimension provide an alternative explanation to gravity.

Keywords: dimensions, four, gravity, voluceleration

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4128 'Performance-Based' Seismic Methodology and Its Application in Seismic Design of Reinforced Concrete Structures

Authors: Jelena R. Pejović, Nina N. Serdar

Abstract:

This paper presents an analysis of the “Performance-Based” seismic design method, in order to overcome the perceived disadvantages and limitations of the existing seismic design approach based on force, in engineering practice. Bearing in mind, the specificity of the earthquake as a load and the fact that the seismic resistance of the structures solely depends on its behaviour in the nonlinear field, traditional seismic design approach based on force and linear analysis is not adequate. “Performance-Based” seismic design method is based on nonlinear analysis and can be used in everyday engineering practice. This paper presents the application of this method to eight-story high reinforced concrete building with combined structural system (reinforced concrete frame structural system in one direction and reinforced concrete ductile wall system in other direction). The nonlinear time-history analysis is performed on the spatial model of the structure using program Perform 3D, where the structure is exposed to forty real earthquake records. For considered building, large number of results were obtained. It was concluded that using this method we could, with a high degree of reliability, evaluate structural behavior under earthquake. It is obtained significant differences in the response of structures to various earthquake records. Also analysis showed that frame structural system had not performed well at the effect of earthquake records on soil like sand and gravel, while a ductile wall system had a satisfactory behavior on different types of soils.

Keywords: ductile wall, frame system, nonlinear time-history analysis, performance-based methodology, RC building

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4127 Nematodes, Rotifers, Tardigrades and Diatoms as Vehicles for the Panspermic Transfer of Microbes

Authors: Sulamain Alharbi, Mohammad Khiyami, Reda Amasha, Bassam Al-Johny, Hesham Khalil, Milton Wainwrigh

Abstract:

Nematodes, Rotifers and Tardigrades (NRT) are extreme-tolerant invertebrates which can survive long periods of stasis brought about by extreme drying and cold. They can also resist the effects of UV radiation, and as a result could act as vehicles for the panspermic transfer of microorganisms. Here we show that NRT contain a variety of bacteria and fungi within their bodies in which environment they could be protected from the extremes of the space and released into new cosmic environments. Diatoms were also shown to contain viable alga and Escherichia coli and so could also act as panspermic vehicles for the transfer of these and perhaps other microbes through space. Although not studied here, NRT, and possibly diatoms, also carry protozoa and viruses within their bodies and could act as vehicles for the panspermic transfer of an even wider range of microbes than shown here.

Keywords: extromophiles, diatoms, panspermia, survival in space

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4126 The Experimental Study of Cold-Formed Steel Truss Connections Capacity: Screw and Adhesive Connection

Authors: Indra Komara, Kıvanç Taşkin, Endah Wahyuni, Priyo Suprobo

Abstract:

A series of connection tests that were composed of Cold-Formed Steel (CFS) sections were made to investigate the capacity of connections in a roof truss frame. The connection is controlled by using the two-different type of connection i.e. screws connection and adhesive. The variation of screws is also added applying 1 screw, 2 screws, and 3 screws. On the other hand, the percentage of adhesively material is increased by the total area of screws connection which is 50%, 75%, and 100%. Behaviors illustrated by each connection are examined, and the design capacities projected from the current CFS design codes are appealed to the experimental results of the connections. This research analyses the principal factors assisting in the ductile response of the CFS truss frame connection measured to propose recommendations for connection design, and novelty so that the connection respond plastically with a significant capacity for no brittle failure. Furthermore, the comparison connection was considered for the analysis of the connection capacity, which was estimated from the specimen’s maximum load capacity and the load-deformation behavior.

Keywords: adhesive, bolts, capacity, cold-formed steel, connections, truss

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4125 Seismic Performance of RC Frames Equipped with Friction Panels Under Different Slip Load Distributions

Authors: Neda Nabid, Iman Hajirasouliha, Sanaz Shirinbar

Abstract:

One of the most challenging issues in earthquake engineering is to find effective ways to reduce earthquake forces and damage to structural and non-structural elements under strong earthquakes. While friction dampers are the most efficient systems to improve the seismic performance of substandard structures, their optimum design is a challenging task. This research aims to find more appropriate slip load distribution pattern for efficient design of friction panels. Non-linear dynamic analyses are performed on 3, 5, 10, 15, and 20-story RC frame using Drain-2dx software to find the appropriate range of slip loads and investigate the effects of different distribution patterns (cantilever, uniform, triangle, and reverse triangle) under six different earthquake records. The results indicate that using triangle load distribution can significantly increase the energy dissipation capacity of the frame and reduce the maximum inter-storey drift, and roof displacement.

Keywords: friction panels, slip load, distribution patterns, RC frames, energy dissipation

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4124 Performences of Type-2 Fuzzy Logic Control and Neuro-Fuzzy Control Based on DPC for Grid Connected DFIG with Fixed Switching Frequency

Authors: Fayssal Amrane, Azeddine Chaiba

Abstract:

In this paper, type-2 fuzzy logic control (T2FLC) and neuro-fuzzy control (NFC) for a doubly fed induction generator (DFIG) based on direct power control (DPC) with a fixed switching frequency is proposed for wind generation application. First, a mathematical model of the doubly-fed induction generator implemented in d-q reference frame is achieved. Then, a DPC algorithm approach for controlling active and reactive power of DFIG via fixed switching frequency is incorporated using PID. The performance of T2FLC and NFC, which is based on the DPC algorithm, are investigated and compared to those obtained from the PID controller. Finally, simulation results demonstrate that the NFC is more robust, superior dynamic performance for wind power generation system applications.

Keywords: doubly fed induction generator (DFIG), direct power control (DPC), neuro-fuzzy control (NFC), maximum power point tracking (MPPT), space vector modulation (SVM), type 2 fuzzy logic control (T2FLC)

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4123 Structure Design of Vacuum Vessel with Large Openings for Spacecraft Thermal Vacuum Test

Authors: Han Xiao, Ruan Qi, Zhang Lei, Qi Yan

Abstract:

Space environment simulator is a facility used to conduct thermal test for spacecraft, and vacuum vessel is the main body of it. According to the requirements for thermal tests of the spacecraft and its solar array panels, the primary vessel and the side vessels are designed to be a combinative structure connected with aperture, which ratio reaches 0.7. Since the vacuum vessel suffers 0.1MPa external pressure during the process of thermal test, in order to ensure the simulator’s reliability and safety, it’s necessary to calculate the vacuum vessel’s intensity and stability. Based on the impact of large openings to vacuum vessel structure, this paper explored the reinforce design and analytical way of vacuum vessel with large openings, using a large space environment simulator’s vacuum vessel design as an example. Tests showed that the reinforce structure is effective to fulfill the requirements of external pressure and the gravity. This ensured the reliability of the space environment simulator, providing a guarantee for developing the spacecraft.

Keywords: vacuum vessel, large opening, space environment simulator, structure design

Procedia PDF Downloads 503