Search results for: Green buildings
Commenced in January 2007
Frequency: Monthly
Edition: International
Paper Count: 988

Search results for: Green buildings

268 A Comparative Study on Seismic Provisions Made in UBC-1997 and Saudi Building Code for RC Buildings

Authors: S. Nazar, M. A. Ismaeil

Abstract:

This paper presents a comparative study of static analysis procedure for seismic performance based on UBC-1997 and SBC-301-2007(Saudi Arabia). These building codes define different ductility classes and corresponding response reduction factors based on material, configuration and detailing of reinforcements. Codes differ significantly in specifying the procedures to estimate base shear, drift and effective stiffness of structural members. One of the major improvements made in new SBC (based on IBC-2003) is ground motion parameters used for seismic design. In old SBC (based on UBC) maps have been based on seismic zones. However new SBC provide contour maps giving spectral response quantities. In this approach, a case study of RC frame building located in two different cities and with different ductility classes has been performed. Moreover, equivalent static method based on SBC-301 and UBC-1997 is used to explore the variation in results based on two codes, particularly design base shear, lateral loads and story drifts.

Keywords: Ductility Classes, Equivalent Static method, RC Frames, SBC-301-2007, Story drifts, UBC-1997.

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267 Investigating the Geopolymerization Process of Aluminosilicates and Its Impact on the Compressive Strength of the Produced Geopolymers

Authors: Heba Z. Fouad, Tarek M. Madkour, Safwan A. Khedr

Abstract:

This paper investigates multiple factors that impact the formation of geopolymers and their compressive strength to be utilized in construction as an environmentally-friendly material. Bentonite and Kaolinite were thermally calcinated at 750 °C to obtain Metabentonite and Metakaolinite with higher reactivity. Both source materials were activated using a solution of sodium hydroxide (NaOH). Thereafter, samples were cured at different temperatures. The samples were analyzed chemically using a host of spectroscopic techniques. The bulk density and compressive strength of the produced geopolymer pastes were studied. Findings indicate that the ratio of NaOH solution to source material affects the compressive strength, being optimal at 0.54. Moreover, controlled heat curing was proven effective to improve compressive strength. The existence of characteristic Fourier Transform Infrared Spectroscopy (FTIR) peaks at approximately 1020 cm-1 and 460 cm-1 which correspond to the asymmetric stretching vibration of Si-O-T and bending vibration of Si-O-Si, hence, confirming the formation of the target geopolymer.

Keywords: alcination of metakaolinite, compressive strength, FTIR analysis, geopolymer, green cement

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266 Microstructure and Mechanical Properties of Duplex Stainless steel for Anchor Bolt Application

Authors: Gil Hwan Na , Woo Young Jung , Tae Kwon Ha

Abstract:

Most buildings have been using anchor bolts commonly for installing outdoor advertising structures. Anchor bolts of common carbon steel are widely used and often installed indiscriminately by inadequate installation standards. In the area where strong winds frequently blow, falling accidents of outdoor advertising structures can occur and cause a serious disaster, which is very dangerous and to be prevented. In this regard, the development of high-performance anchor bolts is urgently required. In the present study, 25Cr-8Ni-1.5Si-1Mn-0.4C alloy was produced by traditional vacuum induction melting (VIM) for the application of anchor bolt. The alloy composition is revealed as a duplex microstructure from thermodynamic phase analysis by FactSage® and confirmed by metallographic experiment. Addition of Nitrogen to the alloy was found to reduce the ferritic phase domain and significantly increase the hardness and the tensile strength. Microstructure observation revealed mixed structure of austenite and ferrite with fine carbide distributed along the grain and phase boundaries.

Keywords: Anchor bolt, Duplex stainless steel, FactSage®, Hardness, Thermodynamic phase analysis.

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265 Dynamic Instability in High-Rise SMRFs Subjected to Long-Period Ground Motions

Authors: Y. Araki, M. Kim, S. Okayama, K. Ikago, K. Uetani

Abstract:

We study dynamic instability in high-rise steel moment resisting frames (SMRFs) subjected to synthetic long-period ground motions caused by hypothetical huge subduction earthquakes. Since long duration as well as long dominant periods is a characteristic of long-period ground motions, interstory drifts may enter the negative postyield stiffness range many times when high-rise buildings are subjected to long-period ground motions. Through the case studies of 9 high-rise SMRFs designed in accordance with the Japanese design practice in 1980s, we demonstrate that drifting, or accumulation of interstory drifts in one direction, occurs at the lower stories of the SMRFs, if their natural periods are close to the dominant periods of the long-period ground motions. The drifting led to residual interstory drift ratio over 0.01, or to collapse if the design base shear was small.

Keywords: long-period ground motion, P-Delta effect, high-rise steel moment resisting frame (SMRF), subduction earthquake

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264 Modeling of Thermal Processes Associated to an Electric Arc

Authors: Allagui Hatem, Ghodbane Fathi

Abstract:

The primary objective of this paper is to study the thermal effects of the electric arc on the breaker apparatus contacts for forecasting and improving the contact durability. We will propose a model which takes account of the main influence factors on the erosion contacts. This phenomenon is very complicated because the amount of ejected metal is not necessarily constituted by the whole melted metal bath but this depends on the balance of forces on the contact surface. Consequently, to calculate the metal ejection coefficient, we propose a method which consists in comparing the experimental results with the calculated ones. The proposed model estimates the mass lost by vaporization, by droplets ejection and by the extraction mechanism of liquid or solid metal. In the one-dimensional geometry, to calculate of the contact heating, we used Green’s function which expresses the point source and allows the transition to the surface source. However, for the two- dimensional model we used explicit and implicit numerical methods. The results are similar to those found by Wilson’s experiments.

Keywords: Electric arc, thermal effect, erosion, contact, durability.

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263 Application of PSO Technique for Seismic Control of Tall Building

Authors: A. Shayeghi, H. Shayeghi, H. Eimani Kalasar

Abstract:

In recent years, tuned mass damper (TMD) control systems for civil engineering structures have attracted considerable attention. This paper emphasizes on the application of particle swarm application (PSO) to design and optimize the parameters of the TMD control scheme for achieving the best results in the reduction of the building response under earthquake excitations. The Integral of the Time multiplied Absolute value of the Error (ITAE) based on relative displacement of all floors in the building is taken as a performance index of the optimization criterion. The problem of robustly TMD controller design is formatted as an optimization problem based on the ITAE performance index to be solved using the PSO technique which has a story ability to find the most optimistic results. An 11- story realistic building, located in the city of Rasht, Iran is considered as a test system to demonstrate effectiveness of the proposed method. The results analysis through the time-domain simulation and some performance indices reveals that the designed PSO based TMD controller has an excellent capability in reduction of the seismically excited example building.

Keywords: TMD, Particle Swarm Optimization, Tall Buildings, Structural Dynamics.

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262 Productivity and Energy Management in Desert Urban

Authors: Masoud Nasri, Rahele Hekmatpanah

Abstract:

Growing world population has fundamental impacts and often catastrophic on natural habitat. The immethodical consumption of energy, destruction of the forests and extinction of plant and animal species are the consequence of this experience. Urban sustainability and sustainable urban development, that is so spoken these days, should be considered as a strategy, goal and policy, beyond just considering environmental issues and protection. The desert-s climate has made a bunch of problems for its residents. Very hot and dry climate in summers of the Iranian desert areas, when there was no access to modern energy source and mechanical cooling systems in the past, made Iranian architects to design a natural ventilation system in their buildings. The structure, like a tower going upward the roof, besides its ornamental application and giving a beautiful view to the building, was used as a spontaneous ventilation system. In this paper, it has been tried to name the problems of the area and it-s inconvenience, then some answers has pointed out in order to solve the problems and as an alternative solution BADGIR (wind-catcher) has been introduced as a solution knowing that it has been playing a major role in dealing with the problems.

Keywords: Productivity, Sustainable development, hot aridzones, climate design, BADGIR (wind-catcher)

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261 Applying the Integrative Design Process in Architectural Firms: An Analytical Study on Egyptian Firms

Authors: Carole A. El Raheb, Hassan K. Abdel-Salam, Ingi Elcherif

Abstract:

An architect carrying the design process alone is the main reason for the deterioration of the quality of the architectural product as the complexity of the projects makes it a multi-disciplinary work; then, the Integrative Design Process (IDP) must be applied in the architectural firm especially from the early design phases to improve the product’s quality and to eliminate the ignorance of the principles of design causing the occurrence of low-grade buildings. The research explores the Integrative Design (ID) principles that fit in the architectural practice. Constraints facing this application are presented with strategies and solutions to overcome them. A survey questionnaire was conducted to collect data from a number of recognized Egyptian Architecture, Engineering and Construction (AEC) firms that explores their opinions on using the IDP. This survey emphasizes the importance of the IDP in firms and presents the reasons preventing the firms from applying the IDP. The aim here is to investigate the potentials of integrating this approach into architectural firms emphasizing the importance of this application which ensures the realization of the project’s goal and eliminates the reduction in the project’s quality.

Keywords: Application, architectural firms, integrative design principles, integrative design process, the project quality.

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260 Seismic Behaviour of Romanian Ortodox Churches, Modeling of Failure Modes by Rigid Blocks

Authors: Marius Mosoarca, Victor Gioncu, Ovidiu Cosma

Abstract:

Historic religious buildings located in seismic areas have developed different failure mechanisms. Simulation of failure modes is done with computer programs through a nonlinear dynamic analysis or simplified using the method of failure blocks. Currently there are simulation methodologies of failure modes based on the failure rigid blocks method only for Roman Catholic churches type. Due to differences of shape in plan, elevation and construction systems between Orthodox churches and Catholic churches, for the first time there were initiated researches in the development of this simulation methodology for Orthodox churches. In this article are presented the first results from the researches. The theoretical results were compared with real failure modes recorded at an Orthodox church from Banat region, severely damaged by earthquakes in 1991. Simulated seismic response, using a computer program based on finite element method was confirmed by cracks after earthquakes. The consolidation of the church was made according to these theoretical results, realizing a rigid floor connecting all the failure blocks.

Keywords: Dinamic analysis, failure mechanism, rigid blocks seismic simulation.

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259 Investigation of Steady State Infiltration Rate for Different Head Condition

Authors: Nour Aljafari, Mariam, S. Maani, Serter Atabay, Tarig Ali, Said Daker, Lara Daher, Hamad Bukhammas, Mohammed Abou Shakra

Abstract:

This paper aims at determining the soil characteristics that influence the irrigation process of green landscapes and deciding on the optimum amount of water needed for irrigation. The laboratory experiments were conducted using the constant head methodology to determine the soil infiltration rates. The steady state infiltration rate was reached after 10 minutes of infiltration at a rate of 200 mm/hr. The effects of different water heads on infiltration rates were also investigated, and the head of 11 cm was found to be the optimum head for the test. The experimental results showed consistent infiltration results for the range between 11 cm and 15 cm. The study also involved finding the initial moisture content, which ranged between 5% and 25%, and finding the organic content, which occupied 1% to 2% of the soil. These results will be later utilized, using the water balance approach, to estimate the optimum amount of water needed for irrigation for changing weather conditions.

Keywords: Infiltration rate, moisture content, grass type, organic content.

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258 Visualized Flow Patterns around and inside a Two-Sided Wind-Catcher in the Presence of Upstream Structures

Authors: M. Afshin, A. Sohankar, M. Dehghan Manshadi, M. R. Daneshgar, G. R. Dehghan Kamaragi

Abstract:

In this paper, the influence of upstream structures on the flow patternaround and inside the wind-catcher is experimentally investigated by smoke flow visualization techniques. Wind-catchers are an important part of natural ventilation in residential buildings or public places such as shopping centers, libraries, etc. Wind-catchers might be also used in places of high urban densities; hence their potential to provide natural ventilation is dependent on the presence of upstream structures. In this study, the two-sided wind-catcher model was based on a real wind-catcher observed in the city of Yazd, Iran. The present study focuses on the flow patterns around and inside the isolated two-sided wind-catcher, and on a two-sided wind-catcher in the presence of an upstream structure. The results show that the presence of an upstream structure influences the airflow pattern force and direction. Placing a high upstream structure reverses the airflow direction inside the wind-catcher.

Keywords: Natural Ventilation, Smoke Flow Visualization, Two-Sided Wind-Catcher.

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257 Critical Points of Prefabricated Reinforced Concrete Wall Systems of Multi-storey Buildings

Authors: J. Witzany, T. Čejka, R. Zigler

Abstract:

With respect to the dissipation of energy through plastic deformation of joints of prefabricated wall units, the paper points out the principal importance of efficient reinforcement of the prefabricated system at its joints. The method, quality and amount of reinforcement are essential for reaching the necessary degree of joint ductility. The paper presents partial results of experimental research of vertical joints of prefabricated units exposed to monotonously rising loading and repetitive shear force and formulates a conclusion that the limit state of the structure as a whole is preceded by the disintegration of joints, or that the structure tends to pass from linearly elastic behaviour to non-linearly elastic to plastic behaviour by exceeding the proportional elastic limit in joints.Experimental verification on a model of a 7-storey prefabricated structure revealed weak points in its load-bearing systems, mainly at places of critical points around openings situated in close proximity to vertical joints of mutually perpendicularly oriented walls.

Keywords: dissipative energy, dynamic and cycling load repetitive load, working diagrams of joints

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256 Effects of Damper Locations and Base Isolators on Seismic Response of a Building Frame

Authors: Azin Shakibabarough, Mojtaba Valinejadshoubi, Ashutosh Bagchi

Abstract:

Structural vibration means repetitive motion that causes fatigue and reduction of the performance of a structure. An earthquake may release high amount of energy that can have adverse effect on all components of a structure. Therefore, decreasing of vibration or maintaining performance of structures such as bridges, dams, roads and buildings is important for life safety and reducing economic loss. When earthquake or any vibration happens, investigation on parts of a structure which sustain the seismic loads is mandatory to provide a safe condition for the occupants. One of the solutions for reducing the earthquake vibration in a structure is using of vibration control devices such as dampers and base isolators. The objective of this study is to investigate the optimal positions of friction dampers and base isolators for better seismic response of 2D frame. For this purpose, a two bay and six story frame with different distribution formats was modeled and some of their responses to earthquake such as inter-story drift, max joint displacement, max axial force and max bending moment were determined and compared using non-linear dynamic analysis.

Keywords: Fast nonlinear analysis, friction damper, base isolator, seismic vibration control, seismic response.

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255 Geometric Simplification Method of Building Energy Model Based on Building Performance Simulation

Authors: Yan Lyu, Yiqun Pan, Zhizhong Huang

Abstract:

In the design stage of a new building, the energy model of this building is often required for the analysis of the performance on energy efficiency. In practice, a certain degree of geometric simplification should be done in the establishment of building energy models, since the detailed geometric features of a real building are hard to be described perfectly in most energy simulation engine, such as ESP-r, eQuest or EnergyPlus. Actually, the detailed description is not necessary when the result with extremely high accuracy is not demanded. Therefore, this paper analyzed the relationship between the error of the simulation result from building energy models and the geometric simplification of the models. Finally, the following two parameters are selected as the indices to characterize the geometric feature of in building energy simulation: the southward projected area and total side surface area of the building. Based on the parameterization method, the simplification from an arbitrary column building to a typical shape (a cuboid) building can be made for energy modeling. The result in this study indicates that no more than 7% prediction error of annual cooling/heating load will be caused by the geometric simplification for those buildings with the ratio of southward projection length to total perimeter of the bottom of 0.25~0.35, which means this method is applicable for building performance simulation.

Keywords: building energy model, simulation, geometric simplification, design, regression

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254 The Feasibility of Using Milled Glass Wastes in Concrete to Resist Freezing-Thawing Action

Authors: Raed Abendeh, Mousa Bani Baker, Zaydoun Abu Salem, Heham Ahmad

Abstract:

The using of waste materials in the construction industry can reduce the dependence on the natural aggregates which are going at the end to deplete. The glass waste is generated in a huge amount which can make one of its disposals in concrete industry effective not only as a green solution but also as an advantage to enhance the performance of mechanical properties and durability of concrete. This article reports the performance of concrete specimens containing different percentages of milled glass waste as a partial replacement of cement (Powder), when they are subject to cycles of freezing and thawing. The tests were conducted on 75-mm cubes and 75 x 75 x 300-mm prisms. Compressive strength based on laboratory testing and non-destructive ultrasonic pulse velocity test were performed during the action of freezing-thawing cycles (F/T). The results revealed that the incorporation of glass waste in concrete mixtures is not only feasible but also showed generally better strength and durability performance than control concrete mixture. It may be said that the recycling of waste glass in concrete mixes is not only a disposal way, but also it can be an exploitation in concrete industry.

Keywords: Durability, glass waste, freeze-thaw cycles, nondestructive test.

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253 Effect of Inhibitors on Weld Corrosion under Sweet Conditions Using Flow Channel

Authors: Khaled Alawadhi, Abdulkareem Aloraier, Suraj Joshi, Jalal Alsarraf

Abstract:

The aim of this paper is to compare the effectiveness and electrochemical behavior of typical oilfield corrosion inhibitors with previous oilfield corrosion inhibitors under the same electrochemical techniques to control preferential weld corrosion of X65 pipeline steel in artificial seawater saturated with carbon dioxide at a pressure of one bar. A secondary aim is to investigate the conditions under which current reversal takes place. A flow channel apparatus was used in the laboratory to simulate the actual condition that occurs in marine pipelines. Different samples from the parent metal, the weld metal and the heat affected zone in the pipeline steel were galvanically coupled. The galvanic currents flowing between the weld regions were recorded using zero-resistance ammeters and tested under static and flowing conditions in both inhibited and uninhibited media. The results show that a current reversal took place when 30ppm of both green oilfield inhibitors were present, resulting in accelerated weld corrosion.

Keywords: Carbon dioxide, carbon steel, current reversal, inhibitor, weld corrosion.

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252 A Low-Cost Air Quality Monitoring Internet of Things Platform

Authors: Christos Spandonidis, Stefanos Tsantilas, Elias Sedikos, Nektarios Galiatsatos, Fotios Giannopoulos, Panagiotis Papadopoulos, Nikolaos Demagos, Dimitrios Reppas, Christos Giordamlis

Abstract:

In the present paper, a low cost, compact and modular Internet of Things (IoT) platform for air quality monitoring in urban areas is presented. This platform comprises of dedicated low cost, low power hardware and the associated embedded software that enable measurement of particles (PM2.5 and PM10), NO, CO, CO2 and O3 concentration in the air, along with relative temperature and humidity. This integrated platform acts as part of a greater air pollution data collecting wireless network that is able to monitor the air quality in various regions and neighborhoods of an urban area, by providing sensor measurements at a high rate that reaches up to one sample per second. It is therefore suitable for Big Data analysis applications such as air quality forecasts, weather forecasts and traffic prediction. The first real world test for the developed platform took place in Thessaloniki, Greece, where 16 devices were installed in various buildings in the city. In the near future, many more of these devices are going to be installed in the greater Thessaloniki area, giving a detailed air quality map of the city.

Keywords: Distributed sensor system, environmental monitoring, Internet of Things, IoT, Smart Cities.

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251 Bridging Quantitative and Qualitative of Glaucoma Detection

Authors: Noor Elaiza Abdul Khalid, Noorhayati Mohamed Noor, Zamalia Mahmud, Saadiah Yahya, and Norharyati Md Ariff

Abstract:

Glaucoma diagnosis involves extracting three features of the fundus image; optic cup, optic disc and vernacular. Present manual diagnosis is expensive, tedious and time consuming. A number of researches have been conducted to automate this process. However, the variability between the diagnostic capability of an automated system and ophthalmologist has yet to be established. This paper discusses the efficiency and variability between ophthalmologist opinion and digital technique; threshold. The efficiency and variability measures are based on image quality grading; poor, satisfactory or good. The images are separated into four channels; gray, red, green and blue. A scientific investigation was conducted on three ophthalmologists who graded the images based on the image quality. The images are threshold using multithresholding and graded as done by the ophthalmologist. A comparison of grade from the ophthalmologist and threshold is made. The results show there is a small variability between result of ophthalmologists and digital threshold.

Keywords: Digital Fundus Image, Glaucoma Detection, Multithresholding, Segmentation.

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250 Effect of adding Supercritical Carbon Dioxide Extracts of Cinnamomum tamala (Bay Leaf) on Nutraceutical Property of Tofu

Authors: Sudip Ghosh, Probir Kumar Ghosh, Paramita Bhattacharjee

Abstract:

Supercritical carbon dioxide extracts of Cinnamomum tamala (bay) leaves obtained at 55°C, 512 bar was found to have appreciable nutraceutical properties and was successfully employed as value-added ingredients in preparation of tofu. The bay leaf formulated tofu sample was evaluated for physicochemical properties (pH, texture analysis and lipid peroxidation), proximate analysis, phytochemical properties (total phenol content, antioxidant properties and total reducing sugar), microbial load and sensory profile analysis for a storage period of ten days, vis-à-vis an experimental control sample. These assays established the superiority of the tofu sample formulated with supercritical carbon dioxide extract of bay leaf over the control sample. Bay leaf extract formulated tofu is a new green functional food with promising nutraceutical benefits. 

Keywords: Cinnamomum tamala, Physicochemical properties Phytochemical properties, Supercritical carbon dioxide extraction, Tofu.

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249 Selection and Exergy Analysis of Fuel Cell System to Meet all Energy Needs of Residential Buildings

Authors: G.R. Ashari, N.Hedayat, S. Shalbaf, E.Hajidavalloo

Abstract:

In this paper a polymer electrolyte membrane (PEM) fuel cell power system including burner, steam reformer, heat exchanger and water heater has been considered to meet the electrical, heating, cooling and domestic hot water loads of residential building which in Tehran. The system uses natural gas as fuel and works in CHP mode. Design and operating conditions of a PEM fuel cell system is considered in this study. The energy requirements of residential building and the number of fuel cell stacks to meet them have been estimated. The method involved exergy analysis and entropy generation thorough the months of the year. Results show that all the energy needs of the building can be met with 12 fuel cell stacks at a nominal capacity of 8.5 kW. Exergy analysis of the CHP system shows that the increase in the ambient air temperature from 1oC to 40oC, will have an increase of entropy generation by 5.73%.Maximum entropy generates for 15 hour in 15th of June and 15th of July is estimated to amount at 12624 (kW/K). Entropy generation of this system through a year is estimated to amount to 1004.54 GJ/k.year.

Keywords: CHP mode, entropy, exergy, no of fuel cell stacks.

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248 Behavior of Current in a Semiconductor Nanostructure under Influence of Embedded Quantum Dots

Authors: H. Paredes Gutiérrez, S. T. Pérez-Merchancano

Abstract:

Motivated by recent experimental and theoretical developments, we investigate the influence of embedded quantum dot (EQD) of different geometries (lens, ring and pyramidal) in a double barrier heterostructure (DBH). We work with a general theory of quantum transport that accounts the tight-binding model for the spin dependent resonant tunneling in a semiconductor nanostructure, and Rashba spin orbital to study the spin orbit coupling. In this context, we use the second quantization theory for Rashba effect and the standard Green functions method. We calculate the current density as a function of the voltage without and in the presence of quantum dots. In the second case, we considered the size and shape of the quantum dot, and in the two cases, we worked considering the spin polarization affected by external electric fields. We found that the EQD generates significant changes in current when we consider different morphologies of EQD, as those described above. The first thing shown is that the current decreases significantly, such as the geometry of EQD is changed, prevailing the geometrical confinement. Likewise, we see that the current density decreases when the voltage is increased, showing that the quantum system studied here is more efficient when the morphology of the quantum dot changes.

Keywords: Quantum semiconductors, nanostructures, quantum dots, spin polarization.

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247 GeoSEMA: A Modelling Platform, Emerging “GeoSpatial-based Evolutionary and Mobile Agents“

Authors: Mohamed Dbouk, Ihab Sbeity

Abstract:

Spatial and mobile computing evolves. This paper describes a smart modeling platform called “GeoSEMA". This approach tends to model multidimensional GeoSpatial Evolutionary and Mobile Agents. Instead of 3D and location-based issues, there are some other dimensions that may characterize spatial agents, e.g. discrete-continuous time, agent behaviors. GeoSEMA is seen as a devoted design pattern motivating temporal geographic-based applications; it is a firm foundation for multipurpose and multidimensional special-based applications. It deals with multipurpose smart objects (buildings, shapes, missiles, etc.) by stimulating geospatial agents. Formally, GeoSEMA refers to geospatial, spatio-evolutive and mobile space constituents where a conceptual geospatial space model is given in this paper. In addition to modeling and categorizing geospatial agents, the model incorporates the concept of inter-agents event-based protocols. Finally, a rapid software-architecture prototyping GeoSEMA platform is also given. It will be implemented/ validated in the next phase of our work.

Keywords: Location-Trajectory management, GIS, Mobile- Moving Objects/Agents, Multipurpose/Spatiotemporal data, Multi- Agent Systems.

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246 Research on Traditional Rammed Earth Houses in Southern Zhejiang, China: Based on the Theory of Embeddedness

Authors: Han Wu, Jie Wang

Abstract:

Zhejiang’s special geographical environment has created characteristic mountain dwellings with climate adaptability. Among them, the terrain of southern Zhejiang is dominated by mountainous and hilly landforms, and its traditional dwellings have distinctive characteristics. They are often adapted to local conditions and laid out in accordance with the mountains. In order to block the severe winter weather conditions, local traditional building materials such as rammed earth are mostly used. However, with the development of urbanization, traditional villages have undergone large-scale changes, gradually losing their original uniqueness. In order to solve this problem, this paper takes traditional villages around Baishanzu National Park in Zhejiang as an example and selects nine typical villages in Jingning County and Longquan, respectively. Based on field investigations, this paper extracts the environmental adaptability of local traditional rammed earth houses from the perspective of “geographical embeddedness”. And then combined with case analysis, the paper discusses the translation and development of its traditional architectural methods in contemporary rammed earth buildings in southern Zhejiang.

Keywords: Rammed earth building, lighting, ventilation, geographical embeddedness, modernization translation.

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245 Application of “Streamlined” Material Accounting to Estimate Environmental Impact

Authors: Paul Osmond

Abstract:

This paper reports a new application of material accounting techniques to characterise and quantify material stocks and flows at the “neighbourhood" scale. The study area is the main campus of the University of New South Wales in Sydney, Australia. The system boundary is defined by the urban structural unit (USU), a typological construct devised to facilitate assessment of the metabolism of urban systems. A streamlined material flow analysis (MFA) was applied to quantify the stocks and flows of key construction materials within the campus USU over time, drawing on empirical data from a major campus development project. The results are reviewed to assess the efficacy of the method in supporting urban environmental evaluation and design practice, for example to facilitate estimation of significant impacts such as greenhouse gas emissions. It is concluded that linking a service (in this case, teaching students) enabled by a given product (university buildings) to the amount of materials used in creating that product offers a potential way to reduce the environmental impact of that service, through more efficient use of materials.

Keywords: Construction materials, material flow analysis, urban metabolism, urban structural unit.

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244 Consumer Market of Agricultural Products and Agricultural Policy in Georgia

Authors: G. Erkomaishvili, M. Kobalava, T. Lazariashvili, M. Saghareishvili

Abstract:

The article discusses the consumer market of agricultural products and agricultural policy in Georgia. It is noted that development of the strategic areas of the agricultural sector needs a special support. These strategic areas should create the country's major export potential. It is important to develop strategies to access to the international markets, form extensive marketing network etc., which will become the basis for the promotion and revenue growth of the country. The Georgian agricultural sector, with the right state policy and support, can achieve success and gain access to the world market with competitive agricultural products. The paper discusses the current condition of agriculture, export and import of agricultural products and agricultural policy in Georgia. The conducted research concludes the information that there is an increasing demand on the green goods in the world market. Natural and climatic conditions of Georgia give a serious possibility of implementing it. The research presents an agricultural development strategy in Georgia and the findings and based on them recommendations are proposed.

Keywords: Agriculture, agricultural cooperative society agricultural insurance, agricultural policy, export-import of agricultural products.

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243 Optimum Design of Tall Tube-Type Building: An Approach to Structural Height Premium

Authors: Ali Kheyroddin, Niloufar Mashhadiali, Frazaneh Kheyroddin

Abstract:

In last decades, tubular systems employed for tall buildings were efficient structural systems. However, increasing the height of a building leads to an increase in structural material corresponding to the loads imposed by lateral loads. Based on this approach, new structural systems are emerging to provide strength and stiffness with the minimum premium for height. In this research, selected tube-type structural systems such as framed tubes, braced tubes, diagrids and hexagrid systems were applied as a single tube, tubular structures combined with braced core and outrigger trusses on a set of 48, 72, and 96-story, respectively, to improve integrated structural systems. This paper investigated structural material consumption by model structures focusing on the premium for height. Compared analytical results indicated that as the height of the building increased, combination of the structural systems caused the framed tube, hexagrid and braced tube system to pay fewer premiums to material tonnage while in diagrid system, combining the structural system reduced insignificantly the steel material consumption.

Keywords: Braced tube, diagrid, framed tube, hexagrid.

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242 Economic Evaluations Using Genetic Algorithms to Determine the Territorial Impact Caused by High Speed Railways

Authors: Gianluigi De Mare, Tony Leopoldo Luigi Lenza, Rino Conte

Abstract:

The evolution of technology and construction techniques has enabled the upgrading of transport networks. In particular, the high-speed rail networks allow convoys to peak at above 300 km/h. These structures, however, often significantly impact the surrounding environment. Among the effects of greater importance are the ones provoked by the soundwave connected to train transit. The wave propagation affects the quality of life in areas surrounding the tracks, often for several hundred metres. There are substantial damages to properties (buildings and land), in terms of market depreciation. The present study, integrating expertise in acoustics, computering and evaluation fields, outlines a useful model to select project paths so as to minimize the noise impact and reduce the causes of possible litigation. It also facilitates the rational selection of initiatives to contain the environmental damage to the already existing railway tracks. The research is developed with reference to the Italian regulatory framework (usually more stringent than European and international standards) and refers to a case study concerning the high speed network in Italy.

Keywords: Impact, compensation for financial loss, depreciation of property, railway network design, genetic algorithms.

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241 Performance Verification of Seismic Design Codes for RC Frames

Authors: Payam Asadi, Ali Bakhshi

Abstract:

In this study, a frame work for verification of famous seismic codes is utilized. To verify the seismic codes performance, damage quantity of RC frames is compared with the target performance. Due to the randomness property of seismic design and earthquake loads excitation, in this paper, fragility curves are developed. These diagrams are utilized to evaluate performance level of structures which are designed by the seismic codes. These diagrams further illustrate the effect of load combination and reduction factors of codes on probability of damage exceedance. Two types of structures; very high important structures with high ductility and medium important structures with intermediate ductility are designed by different seismic codes. The Results reveal that usually lower damage ratio generate lower probability of exceedance. In addition, the findings indicate that there are buildings with higher quantity of bars which they have higher probability of damage exceedance. Life-cycle cost analysis utilized for comparison and final decision making process.

Keywords: RC frame, fragility curve, performance-base design, life-cycle cost analyses, seismic design codes.

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240 Possibilistic Clustering Technique-Based Traffic Light Control for Handling Emergency Vehicle

Authors: F. Titouna, S. Benferhat, K. Aksa, C. Titouna

Abstract:

A traffic light gives security from traffic congestion,reducing the traffic jam, and organizing the traffic flow. Furthermore,increasing congestion level in public road networks is a growingproblem in many countries. Using Intelligent Transportation Systemsto provide emergency vehicles a green light at intersections canreduce driver confusion, reduce conflicts, and improve emergencyresponse times. Nowadays, the technology of wireless sensornetworks can solve many problems and can offer a good managementof the crossroad. In this paper, we develop a new approach based onthe technique of clustering and the graphical possibilistic fusionmodeling. So, the proposed model is elaborated in three phases. Thefirst one consists to decompose the environment into clusters,following by the fusion intra and inter clusters processes. Finally, wewill show some experimental results by simulation that proves theefficiency of our proposed approach.KeywordsTraffic light, Wireless sensor network, Controller,Possibilistic network/Bayesain network.

Keywords: Traffic light, Wireless sensor network, Controller, Possibilistic network/Bayesain network.

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239 Research on the Impact on Building Temperature and Ventilation by Outdoor Shading Devices in Hot-Humid Area: Through Measurement and Simulation on an Office Building in Guangzhou

Authors: Hankun Lin, Yiqiang Xiao, Qiaosheng Zhan

Abstract:

Shading devices (SDs) are widely used in buildings in the hot-humid climate areas for reducing cooling energy consumption for interior temperature, as the result of reducing the solar radiation directly. Contrasting the surface temperature of materials of SDs to the glass on the building façade could give more analysis for the shading effect. On the other side, SDs are much more used as the independence system on building façade in hot-humid area. This typical construction could have some impacts on building ventilation as well. This paper discusses the outdoor SDs’ effects on the building thermal environment and ventilation, through a set of measurements on a 2-floors office building in Guangzhou, China, which install a dynamic aluminum SD-system around the façade on 2nd-floor. The measurements recorded the in/outdoor temperature, relative humidity, velocity, and the surface temperature of the aluminum panel and the glaze. After that, a CFD simulation was conducted for deeper discussion of ventilation. In conclusion, this paper reveals the temperature differences on the different material of the façade, and finds that the velocity of indoor environment could be reduced by the outdoor SDs.

Keywords: Outdoor shading devices, hot-humid area, temperature, ventilation, measurement, CFD.

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