19,528 research outputs found

    Principles of Management Application in Building Construction Projects: Perspectives of Project Managers’

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    One of the most crucial factors to consider when setting up and managing organizational activities is the application of management principles. Most of the time, organizational failure is attributed to either as a violation of management principles or an organization's inability to establish this precedent in the running of its day-to-day activities. This paper, therefore, focused on the application of the management principles of Henri Fayol in the management of human resources for construction projects. The study utilized a descriptive design using a survey study and explorative design through a literature search. Relevant literature was reviewed to identify management principles for the design of the questionnaire. The population is the core building professionals working as project managers in a construction site of three tertiary institutions in Bauchi. Forty-five (45) questionnaires were distributed and successfully filled and retrieved. SPSS software was used for the analysis. The study used descriptive statistics and the Kruskal-Wallis test for the analysis. The results show that the majority of the respondents (80 %) acknowledged the importance of these principles to the construction industry in the management of human resources in the construction site. Also, the findings revealed that project managers always used most of these principles in the management of human resources in the construction site. Although, lack of planning and motivation, non-adherence to principles and standards, clashes of interest and corruption revealed as top challenges of its implementation on construction site. The finding concludes that the more the respondent works longer on construction sites, the higher the application of these principles in managing human resources on sites

    Influence of Professional Status and Conditions of Services on Teacher Productivity in Primary Schools in Zuru Emirate, Kebbi State, Nigeria

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    This study investigated the influence of professional status and condition of service on teacher productivity in primary schools in Zuru Emirate of Kebbi State. A correlational survey design was adopted for the study. Stratified, proportionate and simple random sampling techniques were used to select 346 teachers out of 3,687. Questionnaire and Teacher Productivity Evaluation Format were used as instruments for data collection. The five-point scale instruments were validated by experts and pilot tested and had reliability indexes of 0.83 and 0.85 respectively, using Cronbach Alpha co-efficient. Findings of the study showed that the level of teacher productivity was rated low; professional status and conditions of service were both rated poor. This unfavourable situation has negatively influenced teacher productivity. It was recommended that strategies be put in place to improve teachers’ productivity in terms of quality of teaching, record keeping and other activities. The status of teaching should be upgraded and primary school teachers to be provided with better conditions of service to enhance their productivit

    Modified palm oil fuel ash (pofa) as quartz replacement for the production of porcelain

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    Utilization of silica rich ash such as palm oil fuel ash (POFA) in the ceramic industry due to the increasing demand for porcelain with improved performance is inevitable. Wastes are produced from the industry in form of empty fruits bunches, kernel and fibers. Palm oil industries burned the waste to produce heat to the boiler and generate electricity, the ash produced is known as palm oil fuel ash. POFA has similar chemical property with quartz, thus can be used as quartz replacement. The objectives of this research are to modify POFA, determined its effect on physico-mechanical properties of porcelain and develop a formulation model. To remove the moisture of POFA, the powder was dried in an oven at 110 °C for 24 hours and ground to a sufficient fineness ≤ 50 μm for 12 hours at 250 rev/min. POFA powder underwent heat and HCL acid treatments. Standard porcelain of 50 % clay, 25 % feldspar and 25 % quartz was adopted. Quartz was substituted with POFA at 0, 15, 20 and 25 wt.% and mixed homogeneously with the composition of porcelain, dry pressed into pallets at 91 MPa and sintered at 1100 °C, 1150 °C, 1200 °C and 1250 °C for 2 hours soaking time. Modified POFA (SiO2, Al2O3, Fe2O3, MgO, CaO, and P2O5) were then added to the optimum composition (1150 °C, 15 wt.% of POFA and 2 molar HCl acid treatment) at 1, 2, 3, 4, 5, 10 and 15 wt. % mixed homogeneously, dry pressed and sintered at 1150 °C to identify their effect on physico-mechanical properties of porcelain. Densification was achieved at lower sintering temperature by addition of POFA. Due to formation of mullite and crystalline phase, the highest values of bulk density, compressive strength, and Vickers micro hardness were found to increase by addition of Fe2O3 at 5 wt. % as 2.515 g/cm3, 177.08 MPa and 829 HV respectively. The results of developed polynomial regression models show a very good prediction similar to the experimental value. Hence, POFA has a greater future in ceramic industry due to its flexibility and chemical properties. It is therefore evidently concluded that, addition of Fe2O3 at 5 wt. % enhanced both physical and mechanical properties of porcelain

    Evolution Equations governed by Lipschitz Continuous Non-autonomous Forms

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    We prove L2L^2-maximal regularity of linear non-autonomous evolutionary Cauchy problem \begin{equation}\label{eq00}\nonumber \dot{u} (t)+A(t)u(t)=f(t) \hbox{ for }\ \hbox{a.e. t}\in [0,T],\quad u(0)=u_0, \end{equation} where the operator A(t)A(t) arises from a time dependent sesquilinear form a(t,.,.)a(t,.,.) on a Hilbert space HH with constant domain V.V. We prove the maximal regularity in HH when these forms are time Lipschitz continuous. We proceed by approximating the problem using the frozen coefficient method developed in \cite{ELKELA11}, \cite{ELLA13} and \cite{LH}. As a consequence, we obtain an invariance criterion for convex and closed sets of $H.

    On Distributed Linear Estimation With Observation Model Uncertainties

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    We consider distributed estimation of a Gaussian source in a heterogenous bandwidth constrained sensor network, where the source is corrupted by independent multiplicative and additive observation noises, with incomplete statistical knowledge of the multiplicative noise. For multi-bit quantizers, we derive the closed-form mean-square-error (MSE) expression for the linear minimum MSE (LMMSE) estimator at the FC. For both error-free and erroneous communication channels, we propose several rate allocation methods named as longest root to leaf path, greedy and integer relaxation to (i) minimize the MSE given a network bandwidth constraint, and (ii) minimize the required network bandwidth given a target MSE. We also derive the Bayesian Cramer-Rao lower bound (CRLB) and compare the MSE performance of our proposed methods against the CRLB. Our results corroborate that, for low power multiplicative observation noises and adequate network bandwidth, the gaps between the MSE of our proposed methods and the CRLB are negligible, while the performance of other methods like individual rate allocation and uniform is not satisfactory

    Spatiotemporal Sediment Nutrient Dynamics of Kware Lake, Nigeria

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    Kware Lake provides life to various forms of aqua flora and fauna, livelihood for fishermen community and food for the local populace. The study was conducted to evaluate nutrient dynamics of the lake’s sediment for a period of 12 months (June 2014 to May 2015). Results reveal that some of the variables studied did not show any variation due to space and time but electrical conductivity (EC), phosphate (PO43-), potassium, sodium and clay texture were able to vary according to months, seasons and stations. They recorded range of 101.3-113 µs/cm, 0.97-1.24 g/Kg, 0.29-0.37 g/kg, 0.62-0.77 g/kg, and 13-14 g/kg respectively. Results therefore suggest and confirmed that sediment has a high accumulation of phosphate, due to decomposition on the sediment bed and low nitrate level in sediment than in surface water

    A comfirmatory factor analysis of a newly integrated multidimensional school engagement scale

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    Inconsistencies in measures of school engagement in the literature have called for a re-conceptualization of the school engagement construct. Although many researchers view school engagement as a multifaceted construct, to our knowledge, none of the available instruments have integrated all the important domains that represent its multifaceted nature. This study is our first attempt to examine the psychometric properties of a newly integrated Multidimensional School Engagement Scale (MSES). Data were gathered from 2,381 secondary school students, aged 14 to 16, from 40 day schools in northern Malaysia. Exploratory factor analysis and confi rmatory factor analytic techniques were used to examine the instrument. Based on the available literature, we posited an a priori hypothesis that the scales could be explained by three fi rst-order factors and one second-order factor. We used SPSS v.12 and AMOS 6.0 to analyze the data. Findings supported our hypothesis that the school engagement construct can be explained by three fi rst-order factors and one hierarchical factor comprising cognitive engagement, behavioural engagement, and psychological engagement sub-scales. Findings also showed acceptable internal consistency reliability for the overall scale and the three specific sub-scales of adolescent school engagement
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