A waste minimisation framework for the procurement of design and build construction projects

Both construction Waste Minimisation (WM) and construction procurement activities play an effective role in attaining sustainability by giving due consideration to the environment, community and social conditions in delivering built assets. The construction industry has a major impact on the environment, both in terms of resource consumption and increasing waste production. Recent figures published by the UK government reveal that construction and demolition activities produce approximately 32% of total waste generated: three times the waste produced by all households combined. However, the current and on-going research in the field of construction WM and management focuses mainly on onsite waste quantification and management; and stakeholders‟ source identification. Little research has been undertaken to evaluate the relationship between Construction Procurement Systems (CPS) and construction waste generation. However, literature emphasises the need for research in this context. This research aims to develop a Procurement Waste Minimisation Framework (PWMF) to enhance WM practices by evaluating the relationship between CPS and construction waste generation. Objectives of the research include: examine construction WM drivers, WM approaches, waste origins and causes; critically review and evaluate current CPS and sustainable procurement practices in the UK; assess the relationship between CPS and construction waste generation; investigate and synthesis Procurement Waste Origins (PWO); examine the most suitable CPS that could potentially embed and sustain WM; develop and validate the PWMF. This research has adopted a survey research design and mixed methods sequential procedure. Data has been gathered through a cross sectional, self-administered postal questionnaire survey (N=258 distributed, n=65 received) and semi-structured interviews (N=17) with procurement managers and sustainability managers from the top 100 UK contracting organisations and quantity surveyors from the top 100 UK quantity surveying organisations. Data analysis techniques include: descriptive statistics; non-parametric tests; and constant comparative method. The PWMF has developed based on the findings of literature review, questionnaire survey and semi-structured interviews and adopting key concepts of problem solving methodology. The PWMF validation method includes: validation questionnaire (N=8) and follow-up semi-structured interviews (N=6) with procurement managers, sustainability managers and quantity surveyors. Key findings which emerged from the study include: CPS do have an impact on waste generation in construction; integrated CPS have major potential to integrate WM strategies; four PWO identified (i.e. uncoordinated early involvement of project stakeholders; ineffective communication and coordination; unclear allocation of WM responsibilities; and inconsistent procurement documentation) and associated sub-waste causes; and the developed PWMF enables to diagnose potential waste origins and causes, and WM improvement measures for design and build projects. The study has made recommendations which, if adopted, will lead to significant improvements in WM practices and sustainable procurement practices in construction. The content should be of interest to contractors, clients, and organisations dealing with procurement, waste and sustainability

A Gamma-frailty proportional hazards model for bivariate interval-censored data

Correlated survival data naturally arise from many clinical and epidemiological studies. For the analysis of such data, the Gamma-frailty proportional hazards (PH) model is a popular choice because the regression parameters have marginal interpretations and the statistical association between the failure times can be explicitly quantified via Kendall’s tau. Despite their popularity, Gamma-frailty PH models for correlated interval-censored data have not received as much attention as analogous models for right-censored data. A Gamma-frailty PH model for bivariate interval-censored data is presented and an easy to implement expectation–maximization (EM) algorithm for model fitting is developed. The proposed model adopts a monotone spline representation for the purposes of approximating the unknown conditional cumulative baseline hazard functions, significantly reducing the number of unknown parameters while retaining modeling flexibility. The EM algorithm was derived from a data augmentation procedure involving latent Poisson random variables. Extensive numerical studies illustrate that the proposed method can provide reliable estimation and valid inference, and is moreover robust to the misspecification of the frailty distribution. To further illustrate its use, the proposed method is used to analyze data from an epidemiological study of sexually transmitted infections

Evaluation of the undergraduate family medicine programme of Faculty of Medicine, University of Kelaniya : quantitative and qualitative student feedback

Background: Worldwide there is an increasing emphasis on the importance of primary care. The ministry of health Sri Lanka issued a directive in 2016 that training of doctors in primary care should be strengthened. Medical students of the Faculty of Medicine, University of Kelaniya follow a 1 month long clinical appointment in family medicine in their fourth year of study. Methods: Feedback is taken from students on completion of the appointment. Half the students from each group complete a pre tested structured feedback questionnaire that consists of answers to questions based on a likert scale with a space for free comments. The other half provide qualitative feedback. In this evaluation data were gathered from 185 (98%) students from all eight clinical groups throughout the year 2016. Quantitative data were analysed using SPSS version 22. Inductive thematic analysis was used to analyse the qualitative data from the Round Robin activity and free comments from the questionnaire. Results: The qualitative feedback provided a richer indepth overview of student ideas on the appointment compared to the quantitative data. In reflection of a desire for learning to be of relevance students wanted clinically oriented teaching focused on management. They preferred active teaching learning methods such as the opportunity to conduct consultations and receive immediate feedback. Students had a high regard for the teaching sessions by general practitioners at their clinics. The appointment had created an interest in the discipline of family medicine which could have an impact on future choice of career. There were indications to suggest that student attitudes towards patients may have evolved to be more patient centred. Students appreciated the inclusive and low stress ambience of the learning environment. Conclusions and recommendations: Regular evaluation of teaching programmes helps maintain accountability of faculty and paves the way for more student centred teaching through the incorporation of students’ views in devising teaching methods. This evaluation found that qualitative feedback provided more descriptive material to reflect on and therefore improve teaching on the programme. It is recommended that more use should be made of qualitative methodologies in programme evaluations

Development of DYNAMIX Policy Mixes - Deliverable 4.2, revised version, of the DYNAMIX project

This report documents the development of the initial dynamic policy mixes that were developed for assessment in the DYNAMIX project. The policy mixes were designed within three different policy areas: overarching policy, land-use and food, and metals and other materials. The policy areas were selected to address absolute decoupling in general and, specifically, the DYNAMIX targets related to the use of virgin metals, the use of arable land and freshwater, the input of the nutrients nitrogen and phosphorus, and emissions of greenhouse gases. Each policy mix was developed within a separate author team, using a common methodological framework that utilize previous findings in the project. Specific drivers and barriers for resource use and resource efficiency are discussed in each policy area. Specific policy objectives and targets are also discussed before the actual policy mix is presented. Each policy mix includes a set of key instruments, which can be embedded in a wider set of supporting and complementary policy instruments. All key instruments are described in the report through responses to a set of predefined questions. The overarching mix includes a broad variety of key instruments. The land-use policy mix emphasizes five instruments to improve food production through, for example, revisions of already existing policy documents. It also includes three instruments to influence the food consumption and food waste. The policy mix on metals and other materials primarily aims at reducing the use of virgin metals through increased recycling, increased material efficiency and environmentally justified material substitution. To avoid simply shifting of burdens, it includes several instruments of an overarching character

English academic literacy: difficulties in writing the introduction section of research articles

Este trabalho discute as dificuldades de um pós-graduando da área de energia na confecção da introdução de um artigo acadêmico em inglês. Duas versões do texto foram analisadas (uma após a instrução e outra após a conferência com a instrutora), comparando-as com os modelos de introdução de Swales (2004) e de Samraj (2002) ensinados no curso. O aluno apresentou os seguintes problemas: a narração como modo de organização retórica do texto, a ausência do movimento 2 dos modelos, uma escolha inadequada de léxico. A combinação desses elementos impediu que o texto apresentasse o valor cultural do gênero textual artigo acadêmico - a autopromoção. Os dados suscitam questionamentos sobre os limites da descrição empírica dos gêneros textuais e de seu ensino

A Study on SSD Aware Scan Operation Optimization in PostgreSQL Database

Cost functions used by query optimizers in database systems are built around the properties of conventional hardware technologies like spin type hard disk drives. But with the rapid development in storage technology several new technologies have emerged to overcome the limitations in conventional storage media. One such storage technology is flash storage type which belongs to the broader category of SSDs (Solid State Devices). In this paper we discuss a study done to optimize scan operation performance in PostgreSQL database running on flash storage media by changing the random block transfer cost parameter to a suitable value

Knowledge seeking behaviours of pre interns and early career doctors in Sri Lanka: A cross sectional study Medical Education

Background: Use of reference sources for medical knowledge has changed dramatically over the last two decades with the introduction of online sources of information. This study analyses the medical knowledge seeking behaviours of pre interns and early career doctors in Sri Lanka. Methods: This cross sectional survey with a convenience sample was conducted at two sites targeting two groups; pre-intern doctors graduated from the Faculty of Medicine, University of Colombo and early career doctors following a postgraduate course at the National Hospital of Sri Lanka. The data collection tool was an online self-administered questionnaire (paper based questionnaires used on request) that probed the patterns of using reference sources for medical knowledge. Results and discussion: The respondents comprised of 52 pre-interns and 34 early career doctors. A majority (98 %) had internet access. Early career doctors preferred online resources significantly more than the pre-interns. However, the utilization of online resources for evidence synthesis and planning research was unsatisfactory in both groups. A significant proportion (35 %) responded that they had never read a systematic review. Only one person in the entire sample had co-authored a review article. Conclusion: The use of online resources by participants seems to be satisfactory with a majority shifting to reliable online resources as a reference point for medical knowledge. However, a closer look at the usage patterns reveal that online resources that can be used for more innovative tasks such as evidence synthesis are grossly under-utilized