Where lean construction and value management meet

The lean construction (LC) community’s key vision and goal is to provide value, yet they are increasingly challenged with understanding and dealing with the concept of value, with reports that value is one of the weakest points. Regardless of the previous studies and contributions already made on the concept of value in LC, the absence of a consistent understanding of value has resulted in misperceptions and indistinct boundaries with other construction value-related disciplines. Without a consistent understanding of value, the full potential of applying value-established concepts will not occur. Thus, the study of different concepts in construction will open new opportunities to deliver value in the future. Literature reviewed only revealed a small number of interdisciplinary comparisons of Lean manufacturing and LC with value management (VM)/value engineering (VE) on value. Secondary data was used to present an in-depth comparison of the principal points of the current practice and theories of LC and VM, which are seen as ways to improve the delivery of value to clients and building users. The study revealed a range of similarities at a high level, which could easily point to an early conclusion that LC and VM are interchangeable, leading to the same goal of value delivery and shared misapplication of cost reduction techniques. However, a more detailed examination indicates significant differences in the philosophy and scope in different areas, including project timing, practitioner duties, and areas of practice which could complement each other. Also the study identified that LC is a broader philosophy which covers more aspects than VM, it is evident that LC has advanced over the years towards discussions on the concept of value. The current work in LC on value relies less on other construction value-related disciplines such as VM, VE and partnering. Furthermore, LC literature still views value as a confusing concept associated with different interpretations, forming the basisof its understanding. The study established that value plays a central role in both LC and VM. Their combination could offer great synergy regarding the concept of value

Appraisal of the Performance of Contingency Cost Provision for Building Projects in Nigeria

The paper appraised performance of contingency allowance in addressing projects’ cost risk. To achieve this aim, impact of contingency provision in some selected building projects were evaluated. Data for the study was collected by means of checklist from 40 completed projects’ files. Furthermore, 100 questionnaires on project cost contingency were randomly distributed to quantity Surveyors out of whom 67 completed responses were returned. The results showed that there is significant difference between projects with and without contingency with respect to the accuracy of cost estimates. The study revealed that although the inclusion of contingency allowance reduces the incidence of project cost overrun, majority of the projects under study (55%) had cost overrun. It was also found that the projects exceeded their initial estimate by an average value of 5.07% where contingency was included and by an average value of 9.52% where contingency was not included. The study showed that there is a lack of application of quantitative risks analysis in the determination of contingency fund. Therefore, to improve the accuracy of cost contingency allowance, application of quantitative risks analysis in its determination has been recommended.Keywords: Contingency, Risks, performance, Building

A framework for implementing target value delivery to enhance value creation in the construction industry

The general view of most construction challenges points towards an inability to deliver value. Value creation has not been established enough in the construction industry, regardless of past initiatives to improve it. The literature review highlights the importance of practices that promote value creation, such as target value design (TVD), which has roots in both lean construction and value management, both of which support project environments with favourable features to generate value. With recent reports of TVD successes in various countries, researchers suggest more studies are needed on its wider applications in other procurement routes employing evidence-based decisions, especially in developing countries. However, the application of TVD in the Nigerian construction industry (NCI) has not been fully explored. Additionally, it is not clear how the current design management practices in the NCI align with the underlying benchmarks and practices of TVD. Attempting to develop an appropriate approach that advances current practice is challenging, largely due to a lack of empirical supportive data. Globally, the basic principles of TVD take time to comprehend and can seem discouraging when implemented for the first time on actual projects; the different levels of collaboration can be easily confused and wrongly used interchangeably in TVD projects, and there is also a need for TVD projects to report on value generation and quality as past research has focused more on cost and time savings. In view of these challenges, this study of the NCI was undertaken to explore the current design management practices in relation to TVD, to implement TVD and to develop and test a framework to support construction stakeholders in the implementation of TVD. The applied nature of Design Science Research (DSR) was deemed appropriate for this research. Both qualitative and quantitative methods were used in this investigation. Data were collected from across the building, highways infrastructure and rail sectors of the NCI through observing 17 projects, conducting four in-depth case studies, conducting 101 interviews, and analysing 189 questionnaire survey responses. Initial results revealed a limited awareness of TVD, and that some fundamental TVD practices recognized by the literature partially aligned with current NCI design management practices. From the case studies findings, the level of implementation of individual TVD benchmarks ranged up to 81%. This is the first recorded case of TVD implementation in the NCI, with findings that support evidence of a positive impact in the literature. TVD has been successfully applied in both design and build and traditional procurement routes, especially at the construction stage of public and private sector projects concerning provisional and prime cost sums. Additionally, TVD in bid process was reported as beneficial as it fostered the early participation of selected tenderers during the tender process. Results reveal that TVD flourishes with both face to face and virtual collaboration. The major conclusion is that value creation can be improved using a more structured process. The findings have highlighted the need for a guide to assist NCI professionals, thus prompting the development of the Framework for Implementing Target Value Delivery (FFITVD) with additional embedded processes and strategy enhancing its contribution, which have not been addressed in other frameworks. Thus, this framework expands over and beyond previous frameworks, which focused more on the pre-design and design stages of projects. Testing the FFITVD on a live construction project revealed that the framework is comprehensive enough to be understood by stakeholders and has the capability of sustaining the implementation of TVD. This research has continued to influence research in the USA, academics in the UK and practice in the NCI

Association between proton pump inhibitor therapy and clostridium difficile infection: a contemporary systematic review and meta-analysis.

Abstract Introduction Emerging epidemiological evidence suggests that proton pump inhibitor (PPI) acid-suppression therapy is associated with an increased risk of Clostridium difficile infection (CDI). Methods Ovid MEDLINE, EMBASE, ISI Web of Science, and Scopus were searched from 1990 to January 2012 for analytical studies that reported an adjusted effect estimate of the association between PPI use and CDI. We performed random-effect meta-analyses. We used the GRADE framework to interpret the findings. Results We identified 47 eligible citations (37 case-control and 14 cohort studies) with corresponding 51 effect estimates. The pooled OR was 1.65, 95% CI (1.47, 1.85), I2 = 89.9%, with evidence of publication bias suggested by a contour funnel plot. A novel regression based method was used to adjust for publication bias and resulted in an adjusted pooled OR of 1.51 (95% CI, 1.26–1.83). In a speculative analysis that assumes that this association is based on causality, and based on published baseline CDI incidence, the risk of CDI would be very low in the general population taking PPIs with an estimated NNH of 3925 at 1 year. Conclusions In this rigorously conducted systemic review and meta-analysis, we found very low quality evidence (GRADE class) for an association between PPI use and CDI that does not support a cause-effect relationship

Effective Rheology of Bubbles Moving in a Capillary Tube

We calculate the average volumetric flux versus pressure drop of bubbles moving in a single capillary tube with varying diameter, finding a square-root relation from mapping the flow equations onto that of a driven overdamped pendulum. The calculation is based on a derivation of the equation of motion of a bubble train from considering the capillary forces and the entropy production associated with the viscous flow. We also calculate the configurational probability of the positions of the bubbles.Comment: 4 pages, 1 figur

BPI-fold (BPIF) containing/plunc protein expression in human fetal major and minor salivary glands.

The aim of this study was to determine expression, not previously described, of PLUNC (palate, lung, and nasal epithelium clone) (BPI-fold containing) proteins in major and minor salivary glands from very early fetal tissue to the end of the second trimester and thus gain further insight into the function of these proteins. Early fetal heads, and major and minor salivary glands were collected retrospectively and glands were classified according to morphodifferentiation stage. Expression of BPI-fold containing proteins was localized through immunohistochemistry. BPIFA2, the major BPI-fold containing protein in adult salivary glands, was detected only in the laryngeal pharynx; the lack of staining in salivary glands suggested salivary expression is either very late in development or is only in adult tissues. Early expression of BPIFA1 was seen in the trachea and nasal cavity with salivary gland expression only seen in late morphodifferentiation stages. BPIFB1 was seen in early neural tissue and at later stages in submandibular and sublingual glands. BPIFA1 is significantly expressed in early fetal oral tissue but BPIFB1 has extremely limited expression and the major salivary BPIF protein (BPIFA2) is not produced in fetal development. Further studies, with more sensitive techniques, will confirm the expression pattern and enable a better understanding of embryonic BPIF protein function

Risk Classification in Global Software Development Using a Machine Learning Approach

Software development through teams at different geographical locations is a trend of modern era, which is not only producing good results without costing lot of money but also productive in relation to its cost, low risk and high return. This shift of perception of working in a group rather than alone is getting stronger day by day and has become an important planning tool and part of their business strategy. In this research classification approaches like SVM and K-NN have been implemented to classify the true positive events of global software development project risk according to Time, Cost and Resource. Comparative analysis has also been performed between these two algorithms to determine the highest accuracy algorithms. Results proved that Support Vector Machine (SVM) performed very well in case of Cost Related Risk and Resource Related Risk. Whereas, KNN is found superior to SVM for Time Related Risk.</p

Alignment of the ALICE Inner Tracking System with cosmic-ray tracks

37 pages, 15 figures, revised version, accepted by JINSTALICE (A Large Ion Collider Experiment) is the LHC (Large Hadron Collider) experiment devoted to investigating the strongly interacting matter created in nucleus-nucleus collisions at the LHC energies. The ALICE ITS, Inner Tracking System, consists of six cylindrical layers of silicon detectors with three different technologies; in the outward direction: two layers of pixel detectors, two layers each of drift, and strip detectors. The number of parameters to be determined in the spatial alignment of the 2198 sensor modules of the ITS is about 13,000. The target alignment precision is well below 10 micron in some cases (pixels). The sources of alignment information include survey measurements, and the reconstructed tracks from cosmic rays and from proton-proton collisions. The main track-based alignment method uses the Millepede global approach. An iterative local method was developed and used as well. We present the results obtained for the ITS alignment using about 10^5 charged tracks from cosmic rays that have been collected during summer 2008, with the ALICE solenoidal magnet switched off.Peer reviewe

Isolation of Lupeol from the Stem Bark of Leptadenia hastata (Pers.) Decne

Dried stem bark powder of Leptadania hastata was subjected to maceration with methanol to afford crude methanol extract, which was partitioned with n-hexane, ethylacetate, chloroform and n- butanol to afford different their respective fractions. Extensive phytochemical screening of the n-hexane fraction using column chromatography resulted to the isolation of a white solid substance. The substance was identified as of lupeol using IR, 1D \u2013 NMR, 2D \u2013 NMR data and by comparison with reference spectral data

Global, regional, and national burden of neurological disorders during 1990-2015: a systematic analysis for the Global Burden of Disease Study 2015

Background Comparable data on the global and country-specific burden of neurological disorders and their trends are crucial for health-care planning and resource allocation. The Global Burden of Diseases, Injuries, and Risk Factors (GBD) Study provides such information but does not routinely aggregate results that are of interest to clinicians specialising in neurological conditions. In this systematic analysis, we quantified the global disease burden due to neurological disorders in 2015 and its relationship with country development level. Methods We estimated global and country-specific prevalence, mortality, disability-adjusted life-years (DALYs), years of life lost (YLLs), and years lived with disability (YLDs) for various neurological disorders that in the GBD classification have been previously spread across multiple disease groupings. The more inclusive grouping of neurological disorders included stroke, meningitis, encephalitis, tetanus, Alzheimer's disease and other dementias, Parkinson's disease, epilepsy, multiple sclerosis, motor neuron disease, migraine, tension-type headache, medication overuse headache, brain and nervous system cancers, and a residual category of other neurological disorders. We also analysed results based on the Socio-demographic Index (SDI), a compound measure of income per capita, education, and fertility, to identify patterns associated with development and how countries fare against expected outcomes relative to their level of development. Findings Neurological disorders ranked as the leading cause group of DALYs in 2015 (250·7 [95% uncertainty interval (UI) 229·1 to 274·7] million, comprising 10·2% of global DALYs) and the second-leading cause group of deaths (9·4 [9·1 to 9·7] million], comprising 16·8% of global deaths). The most prevalent neurological disorders were tension-type headache (1505·9 [UI 1337·3 to 1681·6 million cases]), migraine (958·8 [872·1 to 1055·6] million), medication overuse headache (58·5 [50·8 to 67·4 million]), and Alzheimer's disease and other dementias (46·0 [40·2 to 52·7 million]). Between 1990 and 2015, the number of deaths from neurological disorders increased by 36·7%, and the number of DALYs by 7·4%. These increases occurred despite decreases in age-standardised rates of death and DALYs of 26·1% and 29·7%, respectively; stroke and communicable neurological disorders were responsible for most of these decreases. Communicable neurological disorders were the largest cause of DALYs in countries with low SDI. Stroke rates were highest at middle levels of SDI and lowest at the highest SDI. Most of the changes in DALY rates of neurological disorders with development were driven by changes in YLLs. Interpretation Neurological disorders are an important cause of disability and death worldwide. Globally, the burden of neurological disorders has increased substantially over the past 25 years because of expanding population numbers and ageing, despite substantial decreases in mortality rates from stroke and communicable neurological disorders. The number of patients who will need care by clinicians with expertise in neurological conditions will continue to grow in coming decades. Policy makers and health-care providers should be aware of these trends to provide adequate services