Molecular Dynamics Analysis onI mpact Behaviour of Carbon Nanotubes and Graphene Sheets

Impact behavior of striker on graphene sheet and carbon nanotube is investigated based on molecular dynamics (MD) simulations. A MD simulation is conducted to obtain the maximum dynamic deflections of a square and rectangular single-layered graphene sheets (SLGSs) with various values of side-length and striker parameter. Effect of (i) chirality, (ii) graphene side-length and nanotube length, (iii) striker mass on the maximum dynamic deflections of graphene and nanotube are investigated. The effect of different types of boundary condition on the maximum dynamic deflections is studied for zigzag and armchair SWCNTs with various aspect ratios (Length/Diameter).

Air Dispersion Model for Prediction Fugitive Landfill Gaseous Emission Impact in Ambient Atmosphere

This paper will explore formation of HCl aerosol at atmospheric boundary layers and encourages the uptake of environmental modeling systems (EMSs) as a practice evaluation of gaseous emissions (“framework measures”) from small and medium-sized enterprises (SMEs). The conceptual model predicts greenhouse gas emissions to ecological points beyond landfill site operations. It focuses on incorporation traditional knowledge into baseline information for both measurement data and the mathematical results, regarding parameters influence model variable inputs. The paper has simplified parameters of aerosol processes based on the more complex aerosol process computations. The simple model can be implemented to both Gaussian and Eulerian rural dispersion models. Aerosol processes considered in this study were (i) the coagulation of particles, (ii) the condensation and evaporation of organic vapors, and (iii) dry deposition. The chemical transformation of gas-phase compounds is taken into account photochemical formulation with exposure effects according to HCl concentrations as starting point of risk assessment. The discussion set out distinctly aspect of sustainability in reflection inputs, outputs, and modes of impact on the environment. Thereby, models incorporate abiotic and biotic species to broaden the scope of integration for both quantification impact and assessment risks. The later environmental obligations suggest either a recommendation or a decision of what is a legislative should be achieved for mitigation measures of landfill gas (LFG) ultimately.

A Morphological Examination of Urban Renewal Processes: The Sample of Konya City

This research aims to investigate morphological changes in urban patterns in urban renewal areas by using geographic information systems and to reveal pattern differences that occur before and after urban renewal processes by applying a morphological analysis. The concept of urban morphology is not involved in urban renewal and urban planning practices in Turkey. This situation destroys the structural characteristic of urban space which appears as a consequence of changes at city, street or plot level. Different approaches and renewal interventions to urban settlements, which are formed as a reflection of cultural issues, may have positive and negative results. A morphological analysis has been applied to an urban renewal area that covers 325 ha. in Konya, in which city urban renewal projects have gained speed with the increasing of economic investments in this study. The study mentions urban renewal and urban morphology relationship, varied academic approach on the urban morphology issue, urban morphology components, changes in lots pattern and numerical differences that occur on road, construction and green space ratios that are before and after the renewal project, and the results of the morphological analysis. It is seen that the built-up area has significant differences when compared to the previous situation. The amount of green areas decreased significantly in quantitative terms; the transportation systems has been changed completely; and the property ownership has been reconstructed without taking the previous situation into account. Findings show that urban renewal projects in Turkey are put into practice with a rent-oriented approach without making an in-depth analysis. The paper discusses the morphological dimension of urban renewal projects in Turkey through a case study from Konya city.

A Social Decision Support Mechanism for Group Purchasing

With the advancement of information technology and development of group commerce, people have obviously changed in their lifestyle. However, group commerce faces some challenging problems. The products or services provided by vendors do not satisfactorily reflect customers’ opinions, so that the sale and revenue of group commerce gradually become lower. On the other hand, the process for a formed customer group to reach group-purchasing consensus is time-consuming and the final decision is not the best choice for each group members. In this paper, we design a social decision support mechanism, by using group discussion message to recommend suitable options for group members and we consider social influence and personal preference to generate option ranking list. The proposed mechanism can enhance the group purchasing decision making efficiently and effectively and venders can provide group products or services according to the group option ranking list.

Students as Global Citizens: Lessons from the International Study Tour

Study and work operations are being transformed with the uses of technologies and are consequently becoming global. This paper outlines lessons learned based on the international study tour that Australian Bachelor of Information Systems students undertook. This research identifies that for the study tour to be successful, students need to gain skills that global citizens require. For example, students will need to gain an understanding of local cultures, local customs and habits. Furthermore, students would also need to gain an understanding of how a field of their future career expertise operates in the host country, how study and business are conducted internationally, which tools and technologies are currently being utilized on a global scale, what trends drive future developments world-wide and how business negotiations and collaborations are being undertaken across borders. Furthermore, this research provides a guide to educators who are planning, guiding and running study tours as it outlines the requirements of having a pre-tour preparatory session, carefully planned and executed tour itineraries and post-tour sessions during which students can reflect on their experiences and lessons learned so that they can apply them to future international business visits and ventures.

Enhanced Magnetoelastic Response near Morphotropic Phase Boundary in Ferromagnetic Materials: Experimental and Theoretical Analysis

The morphotropic phase boundary (MPB) recently has attracted constant interest in ferromagnetic systems for obtaining enhanced large magnetoelastic response. In the present study, structural and magnetoelastic properties of MPB involved ferromagnetic Tb1-xGdxFe2 (0≤x≤1) system has been investigated. The change of easy magnetic direction from to with increasing x up MPB composition of x=0.9 is detected by step-scanned [440] synchrotron X-ray diffraction reflections. The Gd substitution for Tb changes the composition for the anisotropy compensation near MPB composition of x=0.9, which was confirmed by the analysis of detailed scanned XRD, magnetization curves and the calculation of the first anisotropy constant K1. The spin configuration diagram accompanied with different crystal structures for Tb1-xGdxFe2 was designed. The calculated first anisotropy constant K1 shows a minimum value at MPB composition of x=0.9. In addition, the large ratio between magnetostriction, and the absolute values of the first anisotropy constant │λS∕K1│ appears at MPB composition, which makes it a potential material for magnetostrictive application. Based on experimental results, a theoretically approach was also proposed to signify that the facilitated magnetization rotation and enhanced magnetoelastic effect near MPB composition are a consequence of the anisotropic flattening of free energy of ferromagnetic crystal. Our work specifies the universal existence of MPB in ferromagnetic materials which is important for substantial improvement of magnetic and magnetostrictive properties and may provide a new route to develop advanced functional materials.

Understanding the Influence on Drivers’ Recommendation and Review-Writing Behavior in the P2P Taxi Service

The booming mobile business has been penetrating the taxi industry worldwide with P2P (peer to peer) taxi services, as an emerging business model, transforming the industry. Parallel with other mobile businesses, member recommendations and online reviews are believed to be very effective with regard to acquiring new users for P2P taxi services. Based on an empirical dataset of the taxi industry in China, this study aims to reveal which factors influence users’ recommendations and review-writing behaviors. Differing from the existing literature, this paper takes the taxi driver’s perspective into consideration and hence selects a group of variables related to the drivers. We built two models to reflect the factors that influence the number of recommendations and reviews posted on the platform (i.e., the app). Our models show that all factors, except the driver’s score, significantly influence the recommendation behavior. Likewise, only one factor, passengers’ bad reviews, is insignificant in generating more drivers’ reviews. In the conclusion, we summarize the findings and limitations of the research.

Considering the Relationship between Architecture and Philosophy: Toyo Ito’s Conceptual Architecture

The aim of this paper is to exemplify the relation of architecture and philosophy over the Japanese architect Toyo Ito’s conceptual architecture. The study is practiced in ‘Architecture and Philosophy Readings’ elective course with 22 sophomore architecture students in Karadeniz Technical University Department of Architecture. It is planned as a workshop, which discusses the design philosophy of Toyo Ito’s buildings and the reflections of concept in his intellectual architecture. So, the paper contains Toyo Ito’s philosophy, his discourses and buildings and also thinking similarities with philosopher Gilles Deleuze. Thus, the workshop of course is about architecture and philosophy relationship. With this aspect, a holistic graphic representation is aimed for Toyo Ito who thinks that everything composes a whole. As a result, it can be said that architect and philosopher interaction in architecture and philosophy relation supports creative thinking. Conceptual architecture of Toyo Ito has philosophical roots and his philosophy can be read over his buildings and can be represent totally via a holistic pattern.

An Analysis of Institutional Environments on Corporate Social Responsibility Practices in Nigerian Renewable Energy Firms

Several studies have proposed a one-size fit all approach to Corporate Social Responsibility (CSR) practices, such that CSR as it applies to developed countries is adapted to developing countries, ignoring the differing institutional environments (such as the regulative, economic, social and political environments), which affects the profitability and practices of businesses operating in them. CSR as it applies to filling institutional gaps in developing countries, was categorized into four themes: environmental protection, product and service innovation, social innovation and local cluster development. Based on the four themes, the study employed a qualitative research approach through the use of interviews and review of available publications to study the influence of institutional environments on CSR practices engaged in by three renewable energy firms operating in Nigeria. Over the course of three 60-minutes sessions with the top management and selected workers of the firms, four propositions were made: regulatory environment influences environmental protection practice of Nigerian renewable firms, economic environment influences product and service innovation practice of Nigerian renewable energy firms, the social environment impacts on social innovation in Nigerian renewable energy firms, and political environment affects local cluster development practice of Nigerian renewable energy firms. It was also observed that beyond institutional environments, the international exposure of an organization’s managers reflected in their approach to CSR. This finding on the influence of international exposure on CSR practices creates an area for further study. Insights from this paper are set to help policy makers in developing countries, CSR managers, and future researchers.

The Effect of Geogrid Reinforcement Pre-Stressing on the Performance of Sand Bed Supporting a Strip Foundation

In this paper, an experimental and numerical study was adopted to investigate the effect geogrid soil reinforcement pre-stressing on the pressure settlement relation of sand bed supporting a strip foundation. The studied parameters include foundation depth and pre-stress ratio for the cases of one and two pre-stressed reinforcement layers. The study reflected that pre-stressing of soil reinforcement resulted in a marked enhancement in reinforced bed soil stiffness compared to the reinforced soil without pre-stress. The best benefit of pre-stressing reinforcement was obtained as the overburden pressure and pre-straining ratio increase. Pre-stressing of double reinforcement topmost layers results in further enhancement of stress strain relation of bed soil.

Planning a Supply Chain with Risk and Environmental Objectives

The main objective of the current work is to introduce sustainability factors in optimizing the supply chain model for process industries. The supply chain models are normally based on purely economic considerations related to costs and profits. To account for sustainability, two additional factors have been introduced; environment and risk. A supply chain for an entire petroleum organization has been considered for implementing and testing the proposed optimization models. The environmental and risk factors were introduced as indicators reflecting the anticipated impact of the optimal production scenarios on sustainability. The aggregation method used in extending the single objective function to multi-objective function is proven to be quite effective in balancing the contribution of each objective term. The results indicate that introducing sustainability factor would slightly reduce the economic benefit while improving the environmental and risk reduction performances of the process industries.

Modeling, Analysis and Control of a Smart Composite Structure

In modern engineering, weight optimization has a priority during the design of structures. However, optimizing the weight can result in lower stiffness and less internal damping, causing the structure to become excessively prone to vibration. To overcome this problem, active or smart materials are implemented. The coupled electromechanical properties of smart materials, used in the form of piezoelectric ceramics in this work, make these materials well-suited for being implemented as distributed sensors and actuators to control the structural response. The smart structure proposed in this paper is composed of a cantilevered steel beam, an adhesive or bonding layer, and a piezoelectric actuator. The static deflection of the structure is derived as function of the piezoelectric voltage, and the outcome is compared to theoretical and experimental results from literature. The relation between the voltage and the piezoelectric moment at both ends of the actuator is also investigated and a reduced finite element model of the smart structure is created and verified. Finally, a linear controller is implemented and its ability to attenuate the vibration due to the first natural frequency is demonstrated.

Numerical Simulation of Punching Shear of Flat Plates with Low Reinforcement

Punching shear failure is usually the governing failure mode of flat plate structures. Punching failure is brittle in nature which induces more vulnerability to this type of structure. In the present study, a 3D finite element model of a flat plate with low reinforcement ratio and without any transverse reinforcement has been developed. Punching shear stress and the deflection data were obtained on the surface of the flat plate as well as through the thickness of the model from numerical simulations. The obtained data were compared with the experimental results. Variation of punching stress with respect to deflection as obtained from numerical results is found to be in good agreement with the experimental results; the range of variation of punching stress is within 5%. The numerical simulation shows an early and gradual onset of nonlinearity, whereas the same is late and abrupt as observed in the experimental results. The range of variation of punching stress for different slab thicknesses between experimental and numerical results is less than 15%. The developed numerical model is useful to complement available punching test series performed in the past. The results obtained from the numerical model will be helpful for designing retrofitting schemes of flat plates.

The Ethio-Eritrea Claims Commission on Use of Force: Issue of Self-Defense or Violation of Sovereignty

A decision that deals with international disputes, be it arbitral or judicial, has to properly reflect objectivity and coherence with existing rules of international law. This paper shows the decision of the Ethio-Eritrea Claims Commission on the jus ad bellum case is bereft of objectivity and coherence, which contributed a disservice to international law on many aspects. The Commission’s decision that holds Eritrea in contravention to Art 2(4) of the UN Charter based on Ethiopia’s contention is flawed. It fails to consider: the illegitimacy of an actual authority established over contested territory through hostile acts, the proper determination of effectivites under international law, the sanctity of colonially determined boundaries, Ethiopia’s prior firm political recognition and undergirds to respect colonial boundary, and Ethio-Eritrea Border Commission’s decision. The paper will also argue that the Commission confused Eritrea’s right of self-defense with the rule against the non-use of force to settle territorial disputes; wherefore its decision sanitizes or sterilizes unlawful change of territory resulted through unlawful use of force to the effect of advantaging aggressions. The paper likewise argues that the decision is so sacrilegious that it disregards the ossified legal finality of colonial boundaries. Moreover, its approach toward armed attack does not reflect the peculiarity of the jus ad bellum case rather it brings about definitional uncertainties and sustains the perception that the law on self-defense is unsettled.

Determination of Optical Constants of Semiconductor Thin Films by Ellipsometry

Ellipsometry is an optical method based on the study of the behavior of polarized light. The light reflected on a surface induces a change in the polarization state which depends on the characteristics of the material (complex refractive index and thickness of the different layers constituting the device). The purpose of this work is to determine the optical properties of semiconductor thin films by ellipsometry. This paper describes the experimental aspects concerning the semiconductor samples, the SE400 ellipsometer principle, and the results obtained by direct measurements of ellipsometric parameters and modelling using appropriate software.

A Textual Analysis of Prospective Teachers’ Social Justice Identity Development and LGBTQ Advocacy

This study examined the influences of including LGBTQ-related content in a multicultural teacher education course on the development of prospective teachers’ social justice identities. Appling a content analysis to 53 reflection texts written by participating prospective teachers in response to the relevant course content, this study deduced the stages of social justice identity development (naïve, acceptance, resistance, redefinition, and internalization) that participants reached during the course. The analysis demonstrated that the participants reached various stages in the social identity development model and none of the participants remained at the naïve stage during/after class. The majority (53%) of the participants reached the internalization stage during the coursework and became conscious about the heterosexual privileges they have had and aware of possible impacts of such privilege on their future LGBTQ students. Also the participants had begun to develop pedagogic action plans and devised applicable teaching strategies for their future students based on the new understanding of heteronormativity. We expect this study will benefit teacher educators and educational administrators who want to address LGBTQ-related issues in their multicultural education programs and/or revisit the goals, directions, and implications of their approach.

On the Evaluation of Critical Lateral-Torsional Buckling Loads of Monosymmetric Beam-Columns

Beam-column elements are defined as structural members subjected to a combination of axial and bending forces. Lateral torsional buckling is one of the major failure modes in which beam-columns that are bent about its strong axis may buckle out of the plane by deflecting laterally and twisting. This study presents a compact closed-form equation that it can be used for calculating critical lateral torsional-buckling load of beam-columns with monosymmetric sections in the presence of a known axial load. Lateral-torsional buckling behavior of beam-columns subjected to constant axial force and various transverse load cases are investigated by using Ritz method in order to establish proposed equation. Lateral-torsional buckling loads calculated by presented formula are compared to finite element model results. ABAQUS software is utilized to generate finite element models of beam-columns. It is found out that lateral-torsional buckling load of beam-columns with monosymmetric sections can be determined by proposed equation and can be safely used in design.

Mathematical Modeling of Wind Energy System for Designing Fault Tolerant Control

This paper addresses the mathematical model of wind energy system useful for designing fault tolerant control. To serve the demand of power, large capacity wind energy systems are vital. These systems are installed offshore where non planned service is very costly. Whenever there is a fault in between two planned services, the system may stop working abruptly. This might even lead to the complete failure of the system. To enhance the reliability, the availability and reduce the cost of maintenance of wind turbines, the fault tolerant control systems are very essential. For designing any control system, an appropriate mathematical model is always needed. In this paper, the two-mass model is modified by considering the frequent mechanical faults like misalignments in the drive train, gears and bearings faults. These faults are subject to a wear process and cause frictional losses. This paper addresses these faults in the mathematics of the wind energy system. Further, the work is extended to study the variations of the parameters namely generator inertia constant, spring constant, viscous friction coefficient and gear ratio; on the pole-zero plot which is related with the physical design of the wind turbine. Behavior of the wind turbine during drive train faults are simulated and briefly discussed.

An Investigation on the Role of Iwan as a Sustainable Element in the Traditional Houses of Different Climatic Regions of Iran

This paper focuses on the performance of Iwan as one of the significant spaces in the traditional architecture of Iran. The aim of this study is to investigate on the role of Iwan in sustainability enhancement of traditional houses of different climatic regions of Iran. Iwan is considered as a semi-open space, which its form and location in the building highly depends to the climatic situation of that region. For that reason, Iwan is recognized as one of the sustainable elements in the traditional houses of Iran, which can provide more comfort with less use of energy. In this study, the history and emergence of Iwan in the traditional architecture of Iran as well as the concept of sustainability in architecture are explained briefly. Then, the change of performance or form of Iwan is analysed in different climatic regions of Iran in accordance to the sustainability concepts. The methods used in this study are descriptive and analytic. Results of this paper verify that studying the sustainability solutions in the traditional architecture of Iran, would be a valuable source of inspiration for the current designers to create an environmental and sustainable architecture for the future.

Analysis of Causality between Defect Causes Using Association Rule Mining

Construction defects are major components that result in negative impacts on project performance including schedule delays and cost overruns. Since construction defects generally occur when a few associated causes combine, a thorough understanding of defect causality is required in order to more systematically prevent construction defects. To address this issue, this paper uses association rule mining (ARM) to quantify the causality between defect causes, and social network analysis (SNA) to find indirect causality among them. The suggested approach is validated with 350 defect instances from concrete works in 32 projects in Korea. The results show that the interrelationships revealed by the approach reflect the characteristics of the concrete task and the important causes that should be prevented.