USING SYSTEM DYNAMICS MODELLING PRINCIPLES TO RESOLVE PROBLEMS OF REWORK IN CONSTRUCTION PROJECTS IN NIGERIA

Rework in construction projects has brought in two major challenges: cost overruns and delay. In this regards a study was conducted by considering various construction projects in the South West part of Nigeria to understand the causes of rework and the interventions to mitigate it. Survey research methodologies followed by the conceptual system dynamics (SD) modelling were used in the analysis. This study identified the sources of rework in construction projects from the design related, the client related and the contractor related issues and attempted to derive policy/strategic interventions to limit or eliminate rework on construction projects and its delivery by using conceptual SD models based on the influence of the variables on rework. The findings include that inappropriate scheduling for time pressure or delay at the planning stage, lack of adherence to the specifications, and non availability of skilled human resource are the major c auses of rework. However, rework in construction projects would be reduced or eliminated through policy interventions, such as, achieving client satisfaction with scheduling for time pressure or delay at the planning stage, adherence to specifications ensu ring quality of work resulting in client satisfaction, and the availability of skilled manpower ensuring quality management

USING SYSTEM DYNAMICS MODELLING PRINCIPLES TO RESOLVE PROBLEMS OF REWORK IN CONSTRUCTION PROJECTS IN NIGERIA

Published ArticleRework in construction projects has brought in two major challenges: cost overruns and delay. In this regards a study was conducted by considering various construction projects in the South West part of Nigeria to understand the causes of rework and the interventions to mitigate it. Survey research methodologies followed by the conceptual system dynamics (SD) modelling were used in the analysis. This study identified the sources of rework in construction projects from the design related, the client related and the contractor related issues and attempted to derive policy/strategic interventions to limit or eliminate rework on construction projects and its delivery by using conceptual SD models based on the influence of the variables on rework. The findings include that inappropriate scheduling for time pressure or delay at the planning stage, lack of adherence to the specifications, and non-availability of skilled human resource are the major causes of rework. However, rework in construction projects would be reduced or eliminated through policy interventions, such as, achieving client satisfaction with scheduling for time pressure or delay at the planning stage, adherence to specifications ensuring quality of work resulting in client satisfaction, and the availability of skilled manpower ensuring quality management

Regenerative ideas for urban roads in South Africa

Published ArticleSafer and reliable infrastructure in cities is a necessity for urban dwellers. The question is whether conventional planning practices would provide solutions before urban roads are labelled as unmanageable sources of fatalities, especially in developing economies. This paper presents how smart mobility can be achieved. Using Bloemfontein in South Africa, a case study was performed to examine the causal feedback relations among the factors prompting mobility. The study revealed that: (a) the use of information and communication technology in everyday functions, instead of large-scale physical movement is crucial; and (b) efficient public transportation systems would assist in developing smart mobility in urban areas. In effect, regenerative ideas that are based on prioritised causal feedback relations should bring about smart mobility, which engenders traffic safety in urban areas

CONTEXTUALISING URBAN ENGINEERING EDUCATION FOR FUTURE CITIES

Published ArticleWhile rapidity in service activities have strengthened the role of urban areas as engines of economic growth, high population density and increased industrialization, has brought needless social and environmental complaints in cities. This phenomenon necessitates a change in societal attitude in favor of the creation of responsible living conditions, which demands requisite skills and knowledge that would shape the cities. Thus, this paper explores the adequacy of current urban engineering education in terms of the knowledge, skills and competencies required to plan and develop future cities. The paper examines how “wicked problems” that marginalize effective sustainable city planning can be addressed through astute understanding of social and environmental challenges, urban governance systems and stakeholder involvement. Based on current education system, initial findings suggest that competencies in urban planning will not necessarily enable students to address challenges related to the development of smart and sustainable cities. Rather, engineering, science and social knowledge, which would engender the ability to predict future social dynamics, should enable graduates to become active drivers of sustainable and livable cities

Magnetic Proximity Effect in YBa₂Cu₃O₇/La_2/3Ca_1/3MnO₃ and YBa₂Cu₃O₇/LaMnO₃₊ Superlattices

Using neutron reflectometry and resonant x-ray techniques we studied the magnetic proximity effect (MPE) in superlattices composed of superconducting YBa₂Cu₃O₇ and ferromagnetic-metallic La0.67Ca0.33MnO₃ or ferromagnetic-insulating LaMnO₃₊. We find that the MPE strongly depends on the electronic state of the manganite layers, being pronounced for the ferromagnetic-metallic La0.67Ca0.33MnO₃ and almost absent for ferromagnetic-insulating LaMnO₃₊. We also detail the change of the magnetic depth profile due to the MPE and provide evidence for its intrinsic nature

Anomalous behavior of acoustic phonon mode and central peak in Pb(Zn1/3Nb2/3)0.85Ti0.15O3 single crystal studied using Brillouin scattering

Brillouin spectroscopic measurements have been carried out on relaxor ferroelectric Pb(Zn1/3Nb2/3)0.85Ti0.15O3 (PZN-PT) single crystal over the temperature range 300-585 K. The longitudinal acoustic phonon begins to soften below 650 K, which is attributed to the Burns temperature (TB). On the other hand, the line width of the longitudinal acoustic (LA) phonon mode exhibits a sharp Landau-Khalatnikov-like maximum and an accompanying anomaly in the LA mode frequency around 463 K, the tetragonal-cubic phase transition temperature (Ttc). In addition, a broad central peak, found below the characteristic intermediate temperature T* ~ 525 K, exhibits critical slowing down upon approaching Ttc indicating an order-disorder nature of the phase transition. The relaxation time of polar nano regions estimated from the broad central peak is found to be same as that obtained for LA phonon mode suggesting an electrostrictive coupling between strain and polarization fluctuations. The activation energy for the PNRs relaxation-dynamics is found to be ~236 meV. Polarized nature of the central peak suggests that the polar nano regions have the tendency to form long-range polar ordering

An assessment of the malaria-related knowledge and practices of Tanzania's drug retailers: exploring the impact of drug store accreditation.

BACKGROUND: Since 2003 Tanzania has upgraded its approximately 7000 drug stores to Accredited Drug Dispensing Outlets (ADDOs), involving dispenser training, introduction of record keeping and enhanced regulation. Prior to accreditation, drug stores could officially stock over-the-counter medicines only, though many stocked prescription-only antimalarials. ADDOs are permitted to stock 49 prescription-only medicines, including artemisinin combination therapies and one form of quinine injectable. Oral artemisinin monotherapies and other injectables were not permitted at any time. By late 2011 conversion was complete in 14 of 21 regions. We explored variation in malaria-related knowledge and practices of drug retailers in ADDO and non-ADDO regions. METHODS: Data were collected as part of the Independent Evaluation of the Affordable Medicines Facility - malaria (AMFm), involving a nationally representative survey of antimalarial retailers in October-December 2011. We randomly selected 49 wards and interviewed all drug stores stocking antimalarials. We compare ADDO and non-ADDO regions, excluding the largest city, Dar es Salaam, due to the unique characteristics of its market. RESULTS: Interviews were conducted in 133 drug stores in ADDO regions and 119 in non-ADDO regions. Staff qualifications were very similar in both areas. There was no significant difference in the availability of the first line antimalarial (68.9% in ADDO regions and 65.2% in non-ADDO regions); both areas had over 98% availability of non-artemisinin therapies and below 3.0% of artemisinin monotherapies. Staff in ADDO regions had better knowledge of the first line antimalarial than non-ADDO regions (99.5% and 91.5%, p = 0.001). There was weak evidence of a lower price and higher market share of the first line antimalarial in ADDO regions. Drug stores in ADDO regions were more likely to stock ADDO-certified injectables than those in non-ADDO regions (23.0% and 3.9%, p = 0.005). CONCLUSIONS: ADDO conversion is frequently cited as a model for improving retail sector drug provision. Drug stores in ADDO regions performed better on some indicators, possibly indicating some small benefits from ADDO conversion, but also weaknesses in ADDO regulation and high staff turnover. More evidence is needed on the value-added and value for money of the ADDO roll out to inform retail policy in Tanzania and elsewhere

Universal health coverage from multiple perspectives: a synthesis of conceptual literature and global debates

Background: There is an emerging global consensus on the importance of universal health coverage (UHC), but no unanimity on the conceptual definition and scope of UHC, whether UHC is achievable or not, how to move towards it, common indicators for measuring its progress, and its long-term sustainability. This has resulted in various interpretations of the concept, emanating from different disciplinary perspectives. This paper discusses the various dimensions of UHC emerging from these interpretations and argues for the need to pay attention to the complex interactions across the various components of a health system in the pursuit of UHC as a legal human rights issue. Discussion: The literature presents UHC as a multi-dimensional concept, operationalized in terms of universal population coverage, universal financial protection, and universal access to quality health care, anchored on the basis of health care as an international legal obligation grounded in international human rights laws. As a legal concept, UHC implies the existence of a legal framework that mandates national governments to provide health care to all residents while compelling the international community to support poor nations in implementing this right. As a humanitarian social concept, UHC aims at achieving universal population coverage by enrolling all residents into health-related social security systems and securing equitable entitlements to the benefits from the health system for all. As a health economics concept, UHC guarantees financial protection by providing a shield against the catastrophic and impoverishing consequences of out-of-pocket expenditure, through the implementation of pooled prepaid financing systems. As a public health concept, UHC has attracted several controversies regarding which services should be covered: comprehensive services vs. minimum basic package, and priority disease-specific interventions vs. primary health care. Summary: As a multi-dimensional concept, grounded in international human rights laws, the move towards UHC in LMICs requires all states to effectively recognize the right to health in their national constitutions. It also requires a human rights-focused integrated approach to health service delivery that recognizes the health system as a complex phenomenon with interlinked functional units whose effective interaction are essential to reach the equilibrium called UHC

DURABILITY CHARACTERISTIC OF COCONUT FIBER AGGREGATE CONCRETE BOND IN LIGHTWEIGHT FOAM CONCRETE

The research paper probes into coconut fibre used as lightweight aggregate in concrete for thermal conditioning, specifically on durability. The durability properties of coconut fibre and coconut fibre lightweight aggregate concrete were examined on the thermal conditioning. The use of coconut fibre aggregate in construction was tested and verified. It ascertained the moisture content and water absorption capacity found to be 4.20% and 24% respectively. These values can be compared to the conventional aggregate used in normal times. The density of coconut fibre was found to be in the range of 550 -650 kg/m3. They are within the specified limits of lightweight aggregate standards. The study conducted a related hydration test on coconut fibre fines with cement. The coconut fibre-cement ratio has been optimized to satisfy the criteria of structural lightweight concrete for insulation and thermal conditioning to ensure durability. The experiments for long-term investigation continued for 365 days on the compressive strength of coconut fibre aggregate concrete for three different curing conditions

Antimicrobials: a global alliance for optimizing their rational use in intra-abdominal infections (AGORA)

Intra-abdominal infections (IAI) are an important cause of morbidity and are frequently associated with poor prognosis, particularly in high-risk patients. The cornerstones in the management of complicated IAIs are timely effective source control with appropriate antimicrobial therapy. Empiric antimicrobial therapy is important in the management of intra-abdominal infections and must be broad enough to cover all likely organisms because inappropriate initial antimicrobial therapy is associated with poor patient outcomes and the development of bacterial resistance. The overuse of antimicrobials is widely accepted as a major driver of some emerging infections (such as C. difficile), the selection of resistant pathogens in individual patients, and for the continued development of antimicrobial resistance globally. The growing emergence of multi-drug resistant organisms and the limited development of new agents available to counteract them have caused an impending crisis with alarming implications, especially with regards to Gram-negative bacteria. An international task force from 79 different countries has joined this project by sharing a document on the rational use of antimicrobials for patients with IAIs. The project has been termed AGORA (Antimicrobials: A Global Alliance for Optimizing their Rational Use in Intra-Abdominal Infections). The authors hope that AGORA, involving many of the world's leading experts, can actively raise awareness in health workers and can improve prescribing behavior in treating IAIs