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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
141

An exploration of the employee's perception of walking : enhancing the walking experience in Kuala Lumpur

Adam, M. January 2014 (has links)
Urban planners in the Transportation Department of Kuala Lumpur, over a period of time, noticed a progressive increase in the influx of privately-owned vehicles into the city and decrease in the modal share of public transport. Over-dependence on cars has encouraged a sedentary lifestyle, an obesity epidemic, social exclusion and increased carbon foot print. This research investigates the factors that have led to the increasing dependency on private vehicles by employees who work in employment centres in Kuala Lumpur city. Deficiencies in urban planning have created a spatial separation between people and workplaces, meaning that the existing built environment and land uses are inadequately coordinated with various modes of transportation which could facilitate the movement of people in the city. This results in long hours of commuting between employment centres and residential areas, and causes severe traffic congestion into the city centre daily. Understanding this real life phenomenon in a holistic manner is vital in order to find or create alternatives to car dependency and traffic congestion, as it will show how people construct the meaning of commuting in their built environment, and how commuting can be beneficial to them. In order to establish these arguments, the research takes a qualitative research approach, collecting data from multiple sources of evidence such as interviews and participant observation. A multiple embedded case study approach was adopted, using two contrasting areas in the city of Kuala Lumpur as samples; both the user and the pedestrian environment were used as units of analysis to measure the research questions. This allowed for the use of cross-case analysis to expose replication logic between the two selected samples, after which the findings were adjusted to form four analytical categories: the user’s understanding and knowledge of walking to the workplace; the use of mixed modes of transportation; physical features that support walking to work; and stakeholders’ involvement. The framework for this research was formed by these analytical categories to meet the research aims of finding ways to improve the employees’ walking experience in the pedestrian environment in the context of Kuala Lumpur city. The results showed that the public have a negative attitude towards walking to work. The data collected revealed that the decision employees make to drive is somewhat uninformed, as they lack a holistic understanding of the benefits of incorporating walking to work as part of their daily routine. A framework is developed which proposes that the current mind-set towards walking can be reversed if the data from the analytical categories mentioned earlier are effectively deployed to enchance the walking experience. The study emphasises on the increased knowledge and better understanding of the situation among the employees in order to choose a sustainable way to travel to and around the city centre. The framework also aims to achieve a holistic understanding of incorporating walking as part of mixed mode transportation to the workplace for a more impactful solution to long-distance trips, and to affect, in a positive manner, the mind-set of people who still depend on cars to commute to work in Kuala Lumpur city.
142

Isolation and characterization of a glycosaminoglycan with anticancer activity

Ogundipe, O. D. January 2015 (has links)
Glycosaminoglycans (GAGs) are a family of complex mixture of linear polysaccharides that are present in both vertebrates and invertebrates. This polysaccharide plays important roles in physiological and pathological conditions, including cancer. In this study, GAGs were isolated from two different fish (whelks and cockles) belonging to mollusc invertebrates. The crude GAGs isolated from each shellfish demonstrated variable selective anti-cancer activities against many cancer cell lines including breast (MDANQ01 and MDA468), leukemia (MOLT-4 and K562) and ovarian (HeLa) cancer. None of the commercial GAGs exhibited any anti-cancer activities against all the cancer cells studied. Previous studies conducted on the isolation of GAGs from molluscs reported mainly its anti-coagulant and anti-inflammatory activities; thus neglecting its record of anti-cancer activity. All purified whelk fractions (A – D & F) obtained failed to show any anti-cancer activity; with the exception of fraction E, which showed equal levels of selective anti-cancer activity against breast cancer cells. Mechanism of cell death caused by the three novel GAGs on cancers cells were investigated via cell cycle analysis and apoptosis detection assay. Cell cycle analysis revealed significant perturbations in the cancer cell cycle showing cell cycle arrests at different stages. Similarly, there were significant apoptosis inductions induced by the three novel GAGs on each of the cell lines investigated. Structural elucidations of the two fish GAGs, using chemical, enzymatic, Polyacrylamide, Superose 12 size exclusion chromatography , gel filtration and SAX-HPLC methods of analysis, revealed the presence of both chondroitin sulfate (CS)/dermatan sulfate (DS)-like and HS-like GAGs. Discrepancies in the structural elucidations of the novel GAG mixtures and the commercial GAGs may be partly responsible for the anti-cancer activity of the novel polysaccharides, as changes in exogenous GAGs structural composition, especially sulfation levels or patterns, can alter its binding to growth factors, which is essential for cell proliferation.
143

A theoretical framework to support facilities maintenance management of higher education institutions buildings in Nigeria

Olowoake, M. A. O. January 2015 (has links)
The processes required in maintaining Higher Education Institutions (HEIs) buildings, and to retain their services and facilities to an acceptable standard in Nigeria is being undermined by insufficient maintenance budget and lack of strategic planning. The aim of the study is to develop a new theoretical strategic framework to support Facilities maintenance management of Higher Education Institutions facilities in Nigeria. The key objectives of the study include: investigating the current theoretical approaches to facilities maintenance management, evaluating works and services departments’ constraints in relation to procurement strategies, maintenance methods, maintenance budgets, post occupancy evaluations, project quality control, sustainable programme, and the influence of culture on project execution. Others objectives include: developing a strategic framework to support facilities maintenance management, and validating its effectiveness and the efficiency. The scope of the study is focussed on the general maintenance of all building elements; services provided in the selected twelve HEIs in south west of Nigeria. The study adopted a mixed method research strategy by conducting series of semi-structured interviews with the directors of works and services of the selected HEIs, and a questionnaire survey of the 36 Technical Officers from the selected HEIs in Nigeria. The qualitative and quantitative data collected were analysed by using thematic analyses and multiple regressions respectively. The findings of the thematic analyses of the interviews reveal that, there was a general shortage of financial resources that allow keeping of backlogs of maintenance and repairs of HEIs buildings across both the federal and state HEIs. The work identified that, the following factors have caused majority of the backlogs of maintenance: low level of overall maintenance budget, delays in releasing cash (maintenance funds), lack of the adoption and use of planned prevent maintenance method, a shortage of in-house technical staff, and the absence of maintenance programmes and maintenance schedules. In addition, the findings of the questionnaire survey identified the largest and the strongest among the variables used (Predictor-Maintenance Budget), it determines the effectiveness and efficiency of the framework to about 58%, and determines at which level, that the smallest and less stronger variables can join together with the largest and strongest variable to make the framework effective in the facilities maintenance management of HEIs facilities in Nigeria. The findings further reveal that: majority of the HEIs works and services departments do not have full complements of technical staff, so they outsource most of their maintenance projects; most HEIs works and services departments do not have maintenance budgets; where the budgets are in place, they do not adopt appropriate techniques for data collection. In most HEIs sampled, the major defects are often caused by long delays in releasing maintenance cash. Other challenges include: use of inappropriate maintenance methods; lack of establishment of a project control unit within the works and services department; inability to prepare and use maintenance control toolkit; over reliance on complaints from the facilities users instead of carrying out post occupancy evaluations; and lack of adequate programmes to maintain the built environments under their management. A framework was subsequently developed to address the challenges and shortcomings discovered through interviews and the questionnaire survey. The key element of the framework is based on the extensive literature review and is the further validated through a series of interviews with senior technical officers from eight out of the twelve HEIs sampled. The interviewees agreed that the framework is valid, adaptable, and will make facilities maintenance management of HEIs facilities in Nigeria cost effective, efficient in running, and ensures the achievement of project quality control and project deliveries in a timely fashion. Key words: Backlog, budget, environment, sustainable, procurement, maintenance and quality.
144

A study of the performance of office workers descending multiple flights of stairs in high rise office buildings in trial evacuations

MacLennan, H. A. January 2013 (has links)
Aim: The Aim of this PhD study is to study the performance of mature age office workers descending multiple flights of stairs in trial evacuations of high rise office buildings in the context of extrinsic and intrinsic factors. Method: A case study process coupled with mixed methods data collection and analysis was selected with the unit of analysis being the office worker descending the stairs. An Exploratory case study involving the reanalysis of data from a similar study was undertaken to confirm the selection of the research method. Six high rise buildings were selected varying from 7 to 36 storeys . Trial evacuations were held and data collected via survey, observation and physical assessment. Two explanatory case studies involving a Delphi group and focus groups classified the main contextual issues as the intrinsic ones of the occupant and the extrinsic ones of Stair Design and Construction, Others on the Stairs and Management/ Maintenance. The other explanatory study comprised a directed content analysis of a two extremely relevant media documents related to multiple flight stair descent. The data was analysed and findings established by generalisation where trends could be explained quantitatively and otherwise via triangulation. Results and Conclusions: Fatigue predicting descent performance ability was determined by triangulation and generalisation. Density could mask fatigue as the result of delays that would allow people to descend at more slowly. Descent performance ability for 50% of the population was 300 metres in 1980 reducing to 240 metres in 2010. The risk of falling related directly to this distance and the spiralling action of turning at each landing . Triangulation showed this action increased the risk of vertigo and dizziness as well as the impact of increased BMI and health conditions on stability. The significant (p<.05) contextual extrinsic factors were found to be stair descent risk, need for clear visibility and support from reachable handrails, trial evacuation strategies and procedures and group dynamics. There are other less significant findings explained by context and the “cause and effect directed” case study research method.
145

Implementing green business models in the UK construction industry : opportunities and challenges

Abuzeinab, A. January 2015 (has links)
Green business models (GBMs) have the potential to deliver a much better performance compared to conventional business models (BMs) in this age of sustainability. The question of how construction companies can transform their BMs based on green value propositions is both highly relevant for management and poorly understood to date. This study empirically investigates GBMs transformations in the UK construction industry. The study closely scrutinises how GBMs are defined and understood by adopting a set of defined five elements from business and management literature: namely, green value proposition (GVP); target group (TG); key activities (KA); key resources (KR); and financial logic (FL). It also identifies changes, benefits, and challenges associated with GBMs to ultimately propose a guideline for GBMs implementation. It adopts a qualitative method to provide a diagnostic exploratory study and conducts 19 semi-structured interviews with academics and managers from various construction companies. This study applies thematic analysis as the main data analysis technique and further analyses and validates the findings by utilising interpretive structural modeling (ISM) and interpretive ranking process (IRP) techniques. ISM and IRP techniques are novel contributions to GBMs and construction research. The emergent findings are then validated and refined by conducting structured interviews with 4 academics and 1 director from a contractor practice. A BM is considered to be green when a business changes element (s) of its BM to create and capture a business opportunity or a proposition for TGs that provides environmental improvement coupled with economic benefits. The key findings reveal that GBMs can link environmental sustainability with economic success in a systematic manner. They show that GBMs transformations require strong change capabilities and radically influence the way in which companies conduct business. In addition, they demonstrate the interrelation between the different GBMs elements and show that the GVP and FL represent the foundation of GBMs. The challenges that emerged from this research include: government constraints; financial constraints; industry constraints; company constrains; and lack of demand. However, the ISM analysis demonstrates that government policies are the root challenges that hinder GBMs transformations. Despite the challenges posed, GBMs have the potential to deliver credibility, financial and long-term viability benefits for construction companies. The study proposes and validates a guideline for GBMs implementation for the UK construction industry. The guideline starts with creating top-management receptiveness and support the importance of capturing green demand to be converted into GVPs. It also stresses the importance of out-sourcing of some of the KA and KR and highlights the function of marketing and promotions. In addition, the guideline includes various reviewing and monitoring points to be fed to the top-management. Although the BMs and GBMs are new in the construction discipline, this research, as far as can be established, is one of the few empirical academic works introducing and defining GBMs in the construction context. This study contributes originally to GBMs research by developing a structured relationship between the different GBMs elements and by ranking the elements with reference to benefit areas. The relationship between the GBM elements informs construction managers that the smallest details are not vital in a GBM instead how every element of it fits together as a whole reinforcing system is important matter. Consequently, the different elements of the GBM should never be analysed or developed in isolation. To capture economic benefits offered by environmental sustainability, construction companies need to concentrate on greening the whole BM rather than products and processes only. Finally, the study draws a list of recommendations for increasing GBMs uptake and suggests further research opportunities, particularly in the areas of GBMs elements and networks. Key words: Business models, construction industry, environmental sustainability, green business models, UK.
146

Human response to environmental noise and vibration from freight and passenger railway traffic

Sharp, C. January 2014 (has links)
There is currently a push to increase the proportion of freight traffic that is transported by rail, which is argued to be a safer, more sustainable and more climate friendly means of freight transportation when compared with road or air transportation. This will result in increased noise and vibration from freight railway traffic, the potential impacts of which are not well known. The aim of this research, therefore, is to further the understanding of the human response to freight railway noise and vibration. Data for this research comes from a field study comprising interviews with respondents and measurements of their vibration exposure. A logistic regression model was created and optimised, and is able to accurately classify 96% of these measured railway vibration signals as freight or passenger signals based on two signal properties that quantify the duration and low frequency content of each signal. Exposure-response relationships are then determined using ordinal probit modelling with fixed thresholds and cumulative ordinal logit models. The results indicate that people are able to distinguish between freight and passenger railway vibration, and that the annoyance response due to freight railway vibration is significantly higher than that due to passenger railway vibration, even for equal levels of exposure. To further investigate this disparity in response, a laboratory study was performed in which subjects were exposed to combined noise and vibration from freight and passenger railway traffic. Through the technique of multidimensional scaling, the subjective responses to these stimuli were analysed to investigate the specific attributes of the stimuli that may lead to the difference in human response. The results of this study suggest that the perception of combined railway noise and vibration takes into account not only the exposure magnitude of the noise and vibration stimuli, but also signal properties such as duration, spectral distribution and envelope modulation. These parameters, and in particular the duration parameter, appear to account for the difference in the human response to freight and passenger railway vibration.
147

Environmental design within the Korean electronics industry : with particular reference to handheld devices

Kim, Y. Y. January 2014 (has links)
The paper will examine the use of eco-design tools within the Korean electronics industry, with particular reference to mobile phone design & manufacture. Economic growth in Korea has been driven by aggressively exporting products, primarily to the US & China. Industries - such as semiconductor fabrication & electronic products - have been at the forefront of this export strategy. With impending environmental legislation threatening many of Korea’s global export markets, this study represents a timely appraisal of the industry’s ability to respond. The paper goes on to consider the extent to which eco-design tools are implemented within the Korean electronics industry, & which are most appropriate in environmental and business perspective. Whilst a simple question, this demands a non-trivial set of answers, each step posing significant problems. This is conditional on both the relevant environmental protocol for each market region, & the development of a means of cross-comparing what are very different metrics of environmental damage. In resolving this, the paper adopts Eco (or Fussler’s) Compass as a graphical representation, & uses this to evaluate the impact of a range of concepts, developed using each of the identified design tools, & based on Lifecycle Analysis (LCA- environmental quantitative evaluations method). The paper concludes by presenting cross comparing in environmental effectiveness against business and major international environmental legislations, ranking each of the tools against eco-benefit, relevance to a particular region/market & cost to the organisation, the latter being measured in times of: current capability; required investment in process; requisite developments in technology (R&D investment &/or licensing); & anticipated problems in cultural adaptation.
148

Transition pathways to sustainable energy infrastructure : the UK experience

Hussaini, M. January 2015 (has links)
Environmental problems such as climate change resulting from greenhouse gas emissions present alarming challenge to carbon intensive energy systems. In response, the European Union at the regional level and the United Kingdom at the national level responded to this development by formulating and implementing proactive low carbon transition policies over the past few decades. Using recent transition theories, this thesis provides explorative analysis of low carbon transition pathways that have taken place and that are likely to take place, in the UK road transport and electricity generation sectors. Using reliable data and information, this research applied the concepts of transition pathway theory (the multi-level and multi-phase perspectives) in the context of energy system (as a socio-technical system) to analyse low carbon energy transition prospects in the two case study sectors. Findings indicate that transition in the road transport sector is currently at the take-off phase of transformation pathway to biofuel blends, hybrid electric vehicles, as well as niche technologies such as battery electric vehicles. For the emergence of an ideal low carbon road system in the UK, it is shown that the transformation pathway is insufficient and the likely pathway sequence to full decarbonisation will be transformation-substitution-de-alignment/re-alignment. On the other hand, the fossil fuel electricity generation sector is currently at the take-off phase of substitution pathway to renewable electricity. For the emergence of a single power generation technology, the result shows that the most likely scenario is the de-alignment/re-alignment pathway. Under this pathway, the power industry will be characterised by loosely coupled grid islands located close to consumers, necessitating bidirectional flows of electricity to balance demand and supply. At the national level, the transition assessment indicates that the overall carbon performance of the UK energy system is successful and is in agreement with the targets set in the Kyoto Protocol.
149

SODAR comparison methods for compatible wind speed estimation

Piper, Benjamin January 2011 (has links)
This thesis includes the results of a PhD study about methods to compare Sonic Detection And Ranging (SODAR) measurements to measurements from other instruments. The study focuses on theoretical analysis, the design of a transponder system for simulating winds and the measurement of the acoustic radiation patterns of SODARs. These methods are integrated to reduce uncertainty in SODAR measurements. Through theoretical analysis it is shown that the effective measurement volume of a range gate is 15% of a cone section based on the SODAR's Full Width Half Maximum (FWHM). Models of the beam pattern are used to calculate the ratio of air passing a turbine to that measured by a SODAR over 10 minutes with values of 3-5% found at 10ms-1. The model is used to find angles where significant Sound Pressure Levels (SPLs) occur close to a SODARs baffle giving the highest chance of fixed echoes. This is converted into an orientation guide for SODAR set-up. The design of a transponder system is detailed that aims to provide a calibration test of the processing applied by a SODAR. Testing has shown that the transponder can determine the Doppler shift equation used by a SODAR although further work is needed to make the system applicable to all SODARs. It is shown that anechoic measurements of single elements are useful for improving array models. Measurements of the FWHM and acoustic tilt angle can be achieved in the field using a tilt mechanism and a Sound Level Meter (SLM) on a 10m mast. The same mechanism can be used to calculate an effective tilt angle using the Bradley technique. It is proposed that these methods are integrated to calculate error slopes for the SODAR measurement with regards to a secondary location. It is shown that the slopes could be between 0 and 5% if the methods are fully realised and a Computational Fluid Dynamics (CFD) model is incorporated.
150

Improving the integration of building design and facilities management

Bu Jawdeh, H. M. January 2013 (has links)
This thesis investigates the relationship between facilities management (FM) and design on construction projects in the Middle East region. Input provided by facilities management, the party responsible for developing and maintaining a facility support services system, is found to be vital for enhancing the design’s supportive function and preventing operation problems from occurring during the occupancy phase. An extensive literature review is undertaken to study both FM and design practices, their responsibilities during a facility’s life cycle and the types of services each discipline provides. The nature of facilities management input into design is also explored. The review of literature reveals a limited integration among the facilities management and design professions, a problem mainly caused by the nature of project delivery processes that prevent external input into the design. Accordingly, the research aims of investigating integration in practice and determining the actions to be taken to improve the situation are developed. The survey method is chosen for carrying out the research, involving FM and design practitioners. Semi-structured interviews are utilised for collecting qualitative rich information on professional views and experiences. Research findings disclose the nature of the relationship between facilities managers and designers as well as the status of their current collaboration on construction projects in the Middle East. FM-related concerns occurring during the occupancy phase are identified to show the prominence of their consideration during the design stage. This research also presents the various benefits of achieving successful integration and identifies the different means which could be implemented to improve the process of integration and avoid negative consequences currently affecting facilities and their occupants.

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