Perceived Causes and Effects of Project Delays: A Study of Government Building Construction Projects in the Central Province of Sri Lanka

The problem of delays in the construction industry is a global phenomenon, and Sri Lanka is no exception. The key objectives of this study are to identify and rank the factors that cause project delays in government construction projects and their effects as perceived by the three primary industry participants, namely the clients, consultants and contractors and assess the differences. A questionnaire survey was conducted to solicit the perceived causes and effects of project delays from clients, consultants and contractors responsible for government building construction projects in the Central province of Sri Lanka. Perceived delay factors of the said primary stakeholders were measured using a five-point Likert scale type statements. The causes and effects were ranked according to their Relative Importance Index (the product of Severity Index and Frequency Index). The Spearman Correlation method and Kruskal-Wallis tests were used to test the difference in the perception among the three primary stakeholders. Data were collected from 32 consultants, 49 contractors and 16 clients. This study identified improper project management by the contractor as the leading cause of project delay. The other main causes in the ranked order are shortage of labour, financial problems of the clients, improper day work planning by contractor, delay in payment process, scope changes, delays in drawings submission, delays in approvals, financial difficulties of the contractor and lack of communication. The highest level of agreement on causes of project delays was observed between clients and contractors whereas the lowest level of agreement was observed between clients and consultants. The main perceived effects of project delays are cost overrun, poor quality of the work, disputes, arbitration, litigation and total abandonment. In relation to the effects of project delays, a high level of agreement was observed among clients, consultants and contractors. Each party had a positive correlation for both causes and effects of project delays with the other two parties, while contractors and clients showed the highest agreement on delays causes. There was a very high correlation for ranked effects between any two parties. Keywords: Construction Projects, Delay Causes, Delay Effects, Clients, Contractors, Consultants, Correlational Analysi

Investigation on Microstructure, Hardness, Wear behavior and Fracture Surface Analysis of Strontium (Sr) and Calcium (Ca) Content A357 Modified Alloy by Statistical Technique

The aluminum alloy are extensively used in several industrial applications. Stir casting is one of the most frequently accepted methods. In the present investigation, how the microstructure, mechanical and wear mechanics of A357 alloy were impacted by the presence of Sr/Ca was investigated. The outcomes revealed that addition of elements (Sr/Ca) enhance the microstructural features. Uniform dispersal of particulates (Sr/ Ca) in Al357 alloy and also the modified structure of silicon (Si) were observed. Hardness of modified alloy was evaluated by using hardness tester. A result reveals that hardness of modified alloy was improved by increasing in the Sr/Ca content. The wear rate of modified alloy was evaluated by using Pin and Disc wear test rig. Test trials were conducted according to Taguchi technique. L27 array was implemented for evaluation of data. The effect of varying parameters (factors) on wear loss and COF were analyzed using ANOVA (Analysis of Variance) method. ANOVA outcomes shown that, the Sr/Ca content has a better significant impact on wear behavior and COF of the modified alloy. A wear fractography result shows the internal fracture structure of a wornout surface which was studied by SEM analysis

Group Replacement Model Using Hidden Markov Model

Group replacement model is applicable to the itemsthat fail completely on usage and the result is groupreplacement age for the entire group of items in the systemirrespective of whether they are functioning or not. GenerallyIndustrial items /equipment get worn with time and usage and itfunctions with decreasing efficiency. The increasing repair andmaintenance cost demands the replacement of items. In thecurrent model an intermediate state called repairablebreakdown state in between functioning and irreparablebreakdown state is considered and the Hidden Markov Model(HMM) is made use of in generating the probabilities of itemsfalling in different states. Replacement decision is madeconsidering money value. The optimal replacement age is thetime bucket ‘t’ at which the average cost of the individualreplacement, repair and the cost of the group of items isminimum

Seasonal concentrations of heavy metals and environmental parameters with reference to the Indian largest wedge clam, Donax scortum (Linnaeus, 1758)

1627-1635Karnataka coast is subjected to several factors of pollution due to several anthropogenic activities. Such activities vary between other development aspects and fishing harbour. Studies on water quality parameters in seawater and heavy metals in wedge clam, Donax scortum (Family: Donacidae) were carried out from Padukere beach. Significant variability in the water quality parameters and heavy metals was observed in Padukere. The concentration of Mn was lower during pre-monsoon followed by post monsoon and monsoon, whereas the concentration of Zn was found to be high during post monsoon season followed by monsoon and pre-monsoon. Zn concentration was the highest in D. scortum compared to earlier studies from other geographical regions. The dendrogram indicated that the pattern clustering showed that seasonal variations in environmental variables and metals were determined by seasonal effects, and the influx and nature of water from Udayawara river. The dendrogram of temporal clustering of monitoring periods at Padukere showed that variation in the environmental parameters and metals in D. scortum were only determined by seasonal effects with transition months. PCA was used to interpret relationships between variables. Perhaps the distribution of metal concentrations is by the nature and frequency of discharge

Investigation on Microstructure, Hardness, Wear behavior and Fracture Surface Analysis of Strontium (Sr) and Calcium (Ca) Content A357 Modified Alloy by Statistical Technique

The aluminum alloy are extensively used in several industrial applications. Stir casting is one of the most frequently accepted methods. In the present investigation, how the microstructure, mechanical and wear mechanics of A357 alloy were impacted by the presence of Sr/Ca was investigated. The outcomes revealed that addition of elements (Sr/Ca) enhance the microstructural features. Uniform dispersal of particulates (Sr/ Ca) in Al357 alloy and also the modified structure of silicon (Si) were observed. Hardness of modified alloy was evaluated by using hardness tester. A result reveals that hardness of modified alloy was improved by increasing in the Sr/Ca content. The wear rate of modified alloy was evaluated by using Pin and Disc wear test rig. Test trials were conducted according to Taguchi technique. L27 array was implemented for evaluation of data. The effect of varying parameters (factors) on wear loss and COF were analyzed using ANOVA (Analysis of Variance) method. ANOVA outcomes shown that, the Sr/Ca content has a better significant impact on wear behavior and COF of the modified alloy. A wear fractography result shows the internal fracture structure of a wornout surface which was studied by SEM analysis

An Assessment of the Social Science Research Environment of the Sri Lankan State University System

Higher education institutions play a vital role in society in varied capacities, and one major contribution amongst it all is conducting research as a part of knowledge creation and dissemination. Social Science Research thereby provides valuable input for policy makers, decision makers and the public, in order to encourage the well-being of the society. Previous studies have highlighted the importance of conducting social science researches to address social issues and improve quality of life. However, the number of research conducted in this discipline in Sri Lanka is not adequate when compared to that of other countries in the region. Hence, this study aims to explore the present status and challenges that hinder the number of social science research conducted by academics in State Universities in Sri Lanka. The study conducted a detailed literature review that was followed by in-depth interviews with 50 academics representing five state universities in Sri Lanka. The universities were selected based on the availability of Social Sciences and Humanities Faculties/Departments. The data were then analysed qualitatively based on the Grounded Theory Method to achievestudy objectives. The study revealed three main categories that limit the number of social science researches conducted in State Universities in Sri Lanka. They are; organizational factors, individual factors, and policy related factors. In addition, collaboration with other universities/ faculties, publication opportunities, research awards, and research allowance were identified as aspects in support of social science research in Sri Lanka. The study findings significantly helps in policy making, to identify the present status as well as factors that can contribute to enhance the level of social science related research among academics of State Universities in Sri Lanka.KeywordsResearch Environment, Social Sciences Research, State Universitie

Anti-epileptic effect of Ganoderma lucidum polysaccharides by inhibition of intracellular calcium accumulation and stimulation of expression of CaMKII a in epileptic hippocampal neurons

Purpose: To investigate the mechanism of the anti-epileptic effect of Ganoderma lucidum polysaccharides (GLP), the changes of intracellular calcium and CaMK II a expression in a model of epileptic neurons were investigated. Method: Primary hippocampal neurons were divided into: 1) Control group, neurons were cultured with Neurobasal medium, for 3 hours; 2) Model group I: neurons were incubated with Mg2+ free medium for 3 hours; 3) Model group II: neurons were incubated with Mg2+ free medium for 3 hours then cultured with the normal medium for a further 3 hours; 4) GLP group I: neurons were incubated with Mg2+ free medium containing GLP (0.375 mg/ml) for 3 hours; 5) GLP group II: neurons were incubated with Mg2+ free medium for 3 hours then cultured with a normal culture medium containing GLP for a further 3 hours. The CaMK II a protein expression was assessed by Western-blot. Ca2+ turnover in neurons was assessed using Fluo-3/AM which was added into the replacement medium and Ca2+ turnover was observed under a laser scanning confocal microscope. Results: The CaMK II a expression in the model groups was less than in the control groups, however, in the GLP groups, it was higher than that observed in the model group. Ca2+ fluorescence intensity in GLP group I was significantly lower than that in model group I after 30 seconds, while in GLP group II, it was reduced significantly compared to model group II after 5 minutes. Conclusion: GLP may inhibit calcium overload and promote CaMK II a expression to protect epileptic neuron

Intervention effects of Ganoderma lucidum spores on epileptiform discharge hippocampal neurons and expression of Neurotrophin-4 and N-Cadherin

Epilepsy can cause cerebral transient dysfunctions. Ganoderma lucidum spores (GLS), a traditional Chinese medicinal herb, has shown some antiepileptic effects in our previous studies. This was the first study of the effects of GLS on cultured primary hippocampal neurons, treated with Mg2+ free medium. This in vitro model of epileptiform discharge hippocampal neurons allowed us to investigate the anti-epileptic effects and mechanism of GLS activity. Primary hippocampal neurons from <1 day old rats were cultured and their morphologies observed under fluorescence microscope. Neurons were confirmed by immunofluorescent staining of neuron specific enolase (NSE). Sterile method for GLS generation was investigated and serial dilutions of GLS were used to test the maximum non-toxic concentration of GLS on hippocampal neurons. The optimized concentration of GLS of 0.122 mg/ml was identified and used for subsequent analysis. Using the in vitro model, hippocampal neurons were divided into 4 groups for subsequent treatment i) control, ii) model (incubated with Mg2+ free medium for 3 hours), iii) GLS group I (incubated with Mg2+ free medium containing GLS for 3 hours and replaced with normal medium and incubated for 6 hours) and iv) GLS group II (neurons incubated with Mg2+ free medium for 3 hours then replaced with a normal medium containing GLS for 6 hours). Neurotrophin-4 and N-Cadherin protein expression were detected using Western blot. The results showed that the number of normal hippocampal neurons increased and the morphologies of hippocampal neurons were well preserved after GLS treatment. Furthermore, the expression of neurotrophin-4 was significantly increased while the expression of N-Cadherin was decreased in the GLS treated group compared with the model group. This data indicates that GLS may protect hippocampal neurons by promoting neurotrophin-4 expression and inhibiting N-Cadherin expression

Changes in cortical and striatal neurons predict behavioral and electrophysiological abnormalities in a transgenic murine model of Huntington\u27s disease

Neurons in Huntington\u27s disease exhibit selective morphological and subcellular alterations in the striatum and cortex. The link between these neuronal changes and behavioral abnormalities is unclear. We investigated relationships between essential neuronal changes that predict motor impairment and possible involvement of the corticostriatal pathway in developing behavioral phenotypes. We therefore generated heterozygote mice expressing the N-terminal one-third of huntingtin with normal (CT18) or expanded (HD46, HD100) glutamine repeats. The HD mice exhibited motor deficits between 3 and 10 months. The age of onset depended on an expanded polyglutamine length; phenotype severity correlated with increasing age. Neuronal changes in the striatum (nuclear inclusions) preceded the onset of phenotype, whereas cortical changes, especially the accumulation of huntingtin in the nucleus and cytoplasm and the appearance of dysmorphic dendrites, predicted the onset and severity of behavioral deficits. Striatal neurons in the HD mice displayed altered responses to cortical stimulation and to activation by the excitotoxic agent NMDA. Application of NMDA increased intracellular Ca(2+) levels in HD100 neurons compared with wild-type neurons. Results suggest that motor deficits in Huntington\u27s disease arise from cumulative morphological and physiological changes in neurons that impair corticostriatal circuitry