Volume VIII Issue XI

This study examined the empirical relationship between psychological contract and employees’ commitment. The study adopted the survey research design. The study focused on employees of aluminium manufacturing companies in Port Harcourt, Rivers State, Nigeria. Sample size of 140 employees was drawn from the population through a convenience sampling technique. The instrument was validated by two organizational behavioural and business consultancy experts. The reliability of the instrument was ascertained at 0.82 using Crombach Alpha. Spearman Ranking Order Correlation (r) was used for the test of hypotheses through a bivariate analysis (test of hypothesis) using SPSS Version 22 at 0.05 level of significance. Out of 140 questionnaires administered, 120 copies were retrieved. It was found that psychological contract (transactional contract and relational contract) has a significant relationship on employees’ commitment (loyalty and intention to stay). The study concluded the undoubted connect between psychological contract (transactional and relational contracts) and employees’ commitment (loyalty and intention to stay) calls for management’s proactivity towards the accomplishment of psychological contract as to enhance competitive advantage edge while being in business. The study recommended among other things that: Employers and management of the understudied aluminium manufacturing companies must continue to ensure that a realistic perception of the employment relationship is presented to prospective employees and be ready to enhance promises made during this process; Organization must regularly evaluate the changes in employees’ expectations of the organization and what the organization needs to contribute. This will enable her draw a psychological contract (transactional and relational contracts) that befits its employers and employees.

The national projects of all levels, patterns and classification are an urgent and inevitable necessity, which is the hope of Egypt to rebuild the abandoned space, re-exploit its resources and potentials, solve the problem of regional disparity, achieve balance between the regions of the republic and attract new urban communities. In the light of national projects, a new urban map is drawn and to know the developmental role of major national projects, it is necessary to measure the ability of these projects to attract urbanization so that we can promote these projects and properly evaluate the decision to direct investment to them. - Concentration) According to the strategy of urban development with its two main axes, a set of standard criteria was used, and each criterion includes a set of variables. Applied statistical equation to measure the polarization capacity of the new city of El Alamein and stand on its developmental return on the urban map.

Thermoelectric generator is gaining more popularity in the world because it is environmentally friendly and converts waste heat to additional electric power using a temperature gradient between the hot and cold side. This research aims at designing and developing a charcoal powered food vendor stand equipped with a thermoelectric generator to light up the stand at night and generate useful electricity to power mobile devices especially mobile phones. The basic features include a charging station, Barbecue station and Cooktop. Mild steel was used in making the food stand, making it cost-effective. Test was performed between the hours of 10 am to 5 pm local time at every 5 minutes. 4 Channel digital data logging thermometer, connected to K-Type thermocouple was used to measure the temperature of the cooking pot, ambient temperature, as well as temperatures of the heat sink and conductor. Results showed that the power output increases as the difference in temperature between the hot and cold side increased. Also, the maximum power output of about 5 watts was generated from the thermoelectric generator and was used to charge up mobile devices and lights up a led lamp for work at night.

This articles presents variation effect of step – size on the accuracy pattern of an implicit one - step multiderivative method of the form: ∑j=01αjyn+j=∑i=1lhi ∑j=01βij yi n+j ’ αk= +1 which is a variant of the Implicit Multiderivative linear multistep method of the form: ∑j=0kαjyn+j=∑i=1lhi ∑j=0kβij yi n+j ’ αk= +1 (where h is the step size, k is the step number, l is the order of the derivative, α\_j and β\_j are unknown parameters to be determined). Step size (h) of 0.1, 0.01 and 0.001 were used for the implementation of the method to solven on – stiff and stiff initial value problem of first order Ordinary Differential Equation. Accuracy pattern of the method when it was used to solve a non – stiff problem showed that when h=0.01 the computed result was more accurate than when h=0.1 and h=0.001. When the method was used to solve a stiff initial value problem, accuracy improved as the step size (h) reduced. This study therefore confirmed the assertion that reduction in step – size improves accuracy of numerical methods and further showed that for optimal accuracy to be achieved in non - stiff problems, there is limitation to reduction in step size, because h=0.01 gave better result in terms of accuracy than h=0.001.

Construction site is associated with the collection and disposal of wastes such as ceramic tiles and in order to minimize the landfill up in environment, the ceramic tiles was grinded into powder and used as partial substitute of Ordinary Portland Cement (OPC) in concrete. This study investigated the structural properties of powdery ceramic tiles concrete with graded levels: (0%, 5%, 10%, 15% and 20%) of powdery ceramic tiles. Wastes of tiles generated from construction sites were used to replace cement in the production of 1:2:4 mix concrete, at constant water-cement ratio of 0.5, cast in sets of twelve (12) each in 150mm x 150mm x 150mm moulds. The resulting concrete cubes cured for 28 days and tested for absorption, compressive strength and workability of fresh concrete were also carried out in accordance with BS1881, 1983.The result showed that the compressive strength at 28 day were 27.06 N/mm2 27.42 N/mm2, 27.42 N/mm2, 28.77 N/mm2, 21.02 N/mm2 at 0%, 5%, 10%, 15% and 20% respectively. Regarding to the compressive strength values, it was observed that powdery ceramics tiles concrete at 15% replacement has 28.77 N/mm2 compressive strengths at 28 days of crushing after curing. Workability and absorption properties of the powdery ceramic tiles concrete also exhibited the same trend with that of compressive strength. The cost of construction can be reduced by 15%, if 15% of weight of PCT is used as substitute for cement. The research concluded that PCT at 28 days possesses strikingly similar characteristics with normal concrete up to 15% replacement which can be used for normal weight concrete. Suitability of powdery ceramic tiles can be as partial alternative of ordinary Portland cement in concrete production for sustainability in construction.

Wastewater produced from pre-tanning operations in Gombe pre-tannery is directly discharged into the environment resulting in the release of heavy metal ions which when present above required limits pose health hazards. In this work, Doum palm kernel, an agricultural waste was used for the adsorption of copper, iron and zinc ions from Gombe pre-tannery wastewater. The Doum palm kernels were prepared using standard methods and characterized for elemental and oxide composition, functional groups, surface morphology and surface area using X-Ray Flourescence, Fourier Transform Infra-Red, Scanning Electron Microscopy and Brunuaer, Emmet and Teller analytical equipment respectively. The XRF results showed 43.4% K, 18.1% Ag, 13.2% among others with the highest being potassium (K) of 43.4% and a corresponding oxide concentration of 34.1%. Biosorption studies with the kernel showed that it can be used in the reduction of copper, iron and zinc ions with 4.2g doum palm kernel per liter of Gombe pre-tannery wastewater at an equilibrium time of 30 minutes with 57.33%, 54.84% and 98.76% removal for copper, iron and zinc ions respectively. Mixing speed and temperature effects were also studied. Adsorption data were tested using Langmuir, Freundlich and Temkin models. Different error analyses reveal that experimental data fit Temkin for copper, Freundlich for iron and Langmuir isotherm for zinc. Adsorption kinetic models reveal second-order kinetics with chemisorption being the rate limiting step. Thermodynamic results show enthalpy (∆H) of -52.1 kJ/mol and entropy (∆S) of -0.174 kJ/mol for Copper, while ∆H and ∆S for iron were -52.9 kJ/mol and -0.181 kJ/mol respectively. ∆H and ∆S for zinc were + 20.7 kJ/mol and +0.066 kJ/mol for zinc respectively. ∆G values for Copper and iron at 50 0C (-4318 kJ and -5590 kJ) shows non-spontaneous sorption while that of zinc (+602 kJ) shows spontaneous sorption.

An experiment was conducted to study the efficacy of multiple cellophane bagging in the control of cowpea bruchid (*Callosobruchusmaculatus*). The treatments consisted of single, double, triple, 4- layer and 5-layer low density cellophane bagging along with a control. The experiment was laid out in a laboratory using a completely randomized design in five replications. Each batch of seed stored weighed 2 kg and was stored under the same environmental conditions in the laboratory. Data collected after four months of storage included bruchidoviposition, population, number of holes/seed and weight loss. Minitab statistical software was used to carry out the analysis of variance for all the data collected and the treatment means were compared using 95% confidence interval test. Results indicated that bruchidoviposition, population and number of holes/seed decreased significantly (P<0.05) with increasing cellophane layers. Multiple cellophane bagging therefore presented a high potential for use in the control of cowpea bruchids.

This study explored the impact that social media, specifically Facebook and Instagram have on small and medium Enterprises (SMEs). It aimed at investigating the benefits available to SMEs that use Facebook and Instagram for marketing. This work utilized data collection using a structured online survey (Google Forms).The Findings of this study showed that 37.22% of the population size that viewed the questionnaire responded. From the data collected, it was revealed that SMEs make higher sales with higher customer reach on social media compared to offline marketing. It was also seen that 6% of SMEs made sales of NGN100,000 to NGN500,000 monthly and 4.5% of SMEs had 100,000 to 500,000 customer reach on Instagram as against Facebook. The study provided evidence of advantages of utilizing Facebook and Instagram marketing tools in terms of marketing, increased traffic, awareness and revenue. This shows that SMEs should be engaged in digital marketing using Facebook and Instagram Social Media. This will help them to communicate, scale and easily grow effectively with customers on a global scale, opening new opportunities for sales and growth.

The selection of process parameter for obtaining an optimal hardness properties in the heat treatment of A356 aluminium alloy has been done in this study. The samples were produced via chill casting method and machined into standard hardness test samples. The hardness was evaluated by an FIE Vickers hardness tester of MV1-PC model in accordance with ASTM E384 and ASTM E92 standards. The heat treatment condition were solution heat treatment temperature, solution heat treatment time, ageing temperature and ageing time. The effect of each condition on the hardness of this alloy was considered using Taguchi L9 method which was followed by determining the process parameter with the optimal heat treatment condition. The results obtained have been articulated in this report.

The paper studies the variation pattern of refractivity on land with the three major metrological parameters. The measured refractivity was compared with measured temperature, pressure and relative humidity at 100m height. The data were collected at interval of 30minutes for the whole day. Exponential, linear, power series, logarithmic and polynomial regressions were used to analysed the data and predict the refractivity in a day over the eight months in Jos of Nigeria. Correlation analyses were also used base on the predicted regression equations for two months each represents early dry season, late dry season, early rainy season and late rainy season. The study shows that refractivity increases with pressure and relative humidity while decreasing with temperature. The best regression equation of refractivity with pressure, temperature and relative humidity is polynomial equation. The correlation of pressure, temperature and relative humidity ranges from 0.2067-0.7291, 0.2242-0.9061 and 0.6741-0.9686. The correlations in early rainy and dry seasons for humidity and temperature and late rainy for pressure have highest value. Other regression equations for humidity and temperature have better performance and worst in pressure.

The paper analysed the effect of meteorological parameters on tropospheric refractivity in Jos for better planning of wireless communication signal. Jos, capital of Plateau stateis located on latitude 09038'N and longitude 08051'N , north-central of Nigeria. The year was divided into four; early dry season, late dry season, early rainy season and late rainy season.The tropospheric refractivity variation with hours of the day for nine different months was investigated. The data used were collected from NIMET, Nigeria and the analyses were based on ClausianClapeyron’s equation. It was discovered that in most of the months, a minimum refractivity around 240N-Units are recorded between 60% to 70% hours of the day and maximum refractivity around 335N-units are recorded at early hour in the morning and late hours in the night. More so, rainy season has higher refractivity than dry season and it increases from the early rainy season to late season with September having highest refractivity in the year. The percentage error of this analysis varies from 0.26% to 0.38%.

Web applications are becoming the dominant way to provide access to online services such as e-commas, e-banking, hospitals, school portals, etc. and also a valuable target for security attacks. As the use of web applications for some or most services has increased, the sophistication of attacks against these applications has grown as well. To protect web applications, its services and servers against web application related attacks, the multi-layered detection system is proposed in this research work. This technique proposal will enhance the level of protection considering the diverse nature of intrusions. The contemporary methods in IDS such as the Anomaly-based, Signature-based and Policy-based IDS and their challenges are also reviewed. The common web application attacks which are vulnerable to the web application where discussed. The proposed Multi-layered Technique will detect and filter malicious code irrespective of the entry point in as much the code will be encapsulated as part of the HTTP header. Furthermore, to minimize false-positive response (false alerts), the HTML contained variables are prepared before interacting with the rule. Another effort is to eliminate 'UserAgent 'from the HTTP header that would be scanned by the rules.

The anti-plasmodial activity of bush cane (*Costus afer*) stem on albino mice infected with *Plasmodium berghei berghei* was evaluated. Bush cane collected from the wild were defoliated, washed and the stem macerated. The aqueous extract were test for various phytochemicals. Twenty-four albino mice were used for this experiment, and were divided into six groups of four mice per group. Group 1, 2 and 3 were normal, negative and positive controls respectively, while Group 4, 5 and 6 were treated with 100, 200 and 500mg/kg of bush cane extract based on body weights. Results showed that the groups treated with 100 and 200mg/kg had the same chemo suppressive effect of 89.1% while the group treated with 500mg/kg had a chemo suppressive effect of 96.4%. Also, the acute toxicity (LD50) of the extract showed no mortality at the experimental groups. The hematological evaluation of the experimental mice showed that the extract had positive influence on the Erythrocytes (RBC), Leukocytes (WBC), Packed Cell Volume (PCV), Hemoglobin Concentration (HB), and Neutrophils (NEU) and Lymphocytes (LMYP). Data analysis showed that the chemo suppressive effect of *Costus afer* when compared with the chloroquine, at 500mg/kg was not statistically significant but was significant at 100 and 200mg/kg levels. This showed that bush cane has antiplasmodial property and should be recommended for treatment of malaria.

It is difficult to find natural soil that provided high strength and high durability in practice. Construction on the soils of this type cause difficulties and problematic because of soft soils is less stable and massive primary and long term consolidation settlements when subjected to even moderate load increases. To get stronger soil, unbound materials can be stabilized with cementitious materials such as cement, lime, fly ash, bitumen or combination of these. The stabilized soil materials have a higher strength, lower permeability and lower compressibility than the native soil. In this study, waste material emerged from Oltu Stone was used as additive material for stabilization of sandy soil. The Oltu Stone is an organic matter known as geological material. When it is taken from the quarry as raw material and converted into product, a large part of it turns into waste. Therefore, this work aims to research the usability of the Oltu Stone waste to stabilize the grained soils. In the experimental study, 0,5%, 1% and 2% percentages of Oltu Stone waste were added to the grained soils and prepared samples were subjected to related tests. The test results show that the grained soil samples stabilized by Oltu Stone waste have a high compressive strength as compared to natural grained soil samples. Consequently, it is concluded that Oltu Stone waste materials can be successfully used for the stabilization of the grained soils in geotechnical applications.