Hansen and coworkers (Zhang, L; Hansen, E. W.; Helland, I; Hinrichsen, E.; Larsen, Aa.; Roots, J. Macromolecules, 2009, 42 (14), 5189-5195) recently reported on the room temperature crystallinity of a series of ethene-1-hexene copolymers using solid-state ¹H-NMR FID analysis. However, due to the required 10 ms blanking time of the receiver vital information in the initial part of the FID was lost resulting in an underestimation of the sample crystallinity. To compensate for this information loss we made use of the significant increase in T₂ at or above the melting point which enabled the intensity of the FID at time t = 0 to be reliably estimated. Hence, by applying the Curie law the room temperature intensity of the FID was re-evaluated and resulted in an improved crystallinity value. However, it was still too small compared to the crystallinity obtained by solid-state ¹³C-NMR. However, by multiplying the proton FID intensity (determined at the melting point) by a factor of 1.25 before applying the Curie law, the room temperature crystallinity derived from the two different NMR techniques became – within experimental error – consistent. In this work we present experimental evidence that the empirical multiplication factor of 1.25 strictly originates from a non-Curie temperature behaviour of the NMR signal intensity.

Methanol is recognized as a potential renewable energy source for its uses in gasoline blending and direct methanol fuel cells.  This work aims to develop a simulation model that can adequately represent and industrial real-life methanol reactor from a petrochemical plant at steady-state conditions.  The main purpose is to provide a tool for investigating the effects of inlet temperatures, coolant inlet temperatures and velocity on the reactor’s performance under steady-state conditions.  From the results obtained, it is revealed that the simplified model is able to approximate the plant’s operating conditions with sufficient accuracy of less than 5% error.  The validated model allows a better temperatures, feed superficial velocities and coolant inlet temperatures. T his model can serve as a base for future improvement studies on the said reactor.

The signal construction and approximation by sampling at different time moments is one of major target that plays an important role in numerous applications. In many cases, the separation of frequency bands representing periodic or almost periodic behaviors, allows comprehension of the hidden stochastic phenomena involved. In this work the  construction  and the prediction of  random  signals   based on probabilistic distributions of the random signal at the sampling moments are related to the case of electromagnetic compatibility, where   the unintentional generation, propagation and reception of electromagnetic signal energy are analyzed with reference to the unwanted effects (electromagnetic interference ) induced by such energy. The paper shows that the probabilistic normed spaces can be an appropriate framework in the study of some issue in the area of electromagnetic compatibility.

Reports of large-scale outbreaks of fever caused by CHIKV virus infection in several parts of the country especially in Southern India have confirmed the re-emergence of this virus. In 2006, Southern India states Andhra Pradesh, Karnataka, Tamil Nadu and Kerala together contributed more than 70% of the total country’s incidence out which Karnataka state alone contributed nearly 55% of incidence. In 2008, Karnataka and Kerala together contributed more than 95% of the total suspected cases and in 2009 also 41,649 suspected CHIKV cases have been reported and 3,239 cases were confirmed for Karnataka. There is no specific treatment (therapies) or vaccines are available for CHIKV.  But the Homoeopathic system of medicine claims to have medicines as well as preventive measures against this disease.

Indoor air quality (IAQ) issues are not new in Malaysia . However, lack of study, data and local regulation become one of the major contributions towards this problem especially with the non-industrial sector. This study are focusing on the application of related legal requirement, identify source of problem contribute to the IAQ, occupational exposure and control measure required to mitigate the issue in future. It have been perform specifically at the office area facilitate with centralized air conditioning system. A total of 125 samples were performed against the floor area (5000m²)   and specific activities perform within the building. It has been divided into two stages which are based on quantitative and qualitative approach. Walk through survey were conducted and the area sampling were selected for data collection. It shows that 77 % of the IAQ issue comes from inadequate ventilation supply into the building against number of air change rate per occupant range 20 cfm per person. These findings also lead to the identification of high carbon dioxide at the area sampled; microorganism, Total Volatile Organic Compound (TVOC) and relative humidity levels exceed the allowable limit. Carbon dioxide, detected with mod reading at 1300ppm against the ceiling limit of 1000ppm by Code of Practice on IAQ (CoP-IAQ). This situation can be related to 80% of bacterial and fungal count perform exceed the 500 cfu/m³ limit by World Health Organization (WHO). Issue of uncontrolled renovation and lack of awareness among occupant are main contribution toward the IAQ problem as well. TVOC for 8TWA exceed the stipulate value of 3ppm. The CoP-IAQ only covered five common chemical in the indoor setting. However, the study have shown other parameters like microorganism, ventilation rate or physical parameter like temperature and humidity also play a major role as an indoor contaminant agent. This study are believe to help the researcher, occupational practitioner and management to use as baseline toward the management and control of the Indoor Air Quality in indoor settings in terms of pollutant and control measures to minimized the exposure among the occupant.

The objective of this study is the development of an efficient high-order compact scheme for unsteady incompressible viscous flows. The scheme is constructed on a staggered Cartesian grid system in order to avoid spurious oscillations in the pressure field. Navier-Stokes equations are advanced in time with the second order Adams-Bashford method without considering the pressure terms in the predictor step, the velocity field is then corrected such that discrete mass continuity equations satisfied through pressure Poisson equation. Since the efficiency of the fractional step method depends on the Poisson solver, a V-cycle multigrid acceleration with compact Mehrstellen discretization based iterative method is implemented in the pressure Poisson equation to enhance the computational efficiency. The efficiency and accuracy of iterative Poisson solvers (pseudo-time, Jacobi, Gauss-Seidel) are also tested within the multigrid framework. The method is then validated by the simulations of the Taylor-Green vortex decaying problem. Results show that the fractional-step compact scheme with multigrid acceleration has high resolving efficiency that drastically reduces computational time and high-order accuracy making the method applicable for simulation of incompressible viscous flows.

In this study, accurate analytical solution for the nonlinear free vibration of an oscillator with inertia and static type cubic nonlinearities is derived. This solution is called He’s Variational Iteration Method (VIM). Comparing this method with numerical integration solutions using a built-in ODE-solver in MATLAB and He’s Homotopy Analysis Method (HAM) is shown its drastic approximation. By using VIM, only a few iterations lead us to high accuracy of the solutions and it is valid for whole solution domain.

Information literacy is one of the critical digital-age literacies for higher education. Students need to be information literate to cope with the challenges in further studies and future profession. Assessment of students’ information skills is important to determine how information literate they are. This study describes the results of an information skills assessment and has identified the skills that need improvement. It has also identified the type and format of resources students most frequently use in course assignments.

The respondents in the study were diploma-level engineering students who had undergone at least three semesters at a Malaysian college.  Data were collected using a survey instrument adapted from Mittermeyer and triangulated using a citation analysis of student bibliographies in an essay assignment. The results of this study show that the respondents seriously lacked the necessary knowledge and skills to evaluate internet information, to identify the most efficient search strategy, to use scholarly resources, and to use information ethically. Most scholarly resources used were books in print format, while most non-scholarly resources referred to were in electronic format. This study implies the importance of information literacy assessment as the first step in improving students’ information skills. It also indicates the need to encourage students to use more scholarly electronic resources in their coursework. It is suggested that a larger sample of students be used in order to be more representative of the engineering student population. An intervention program should also be introduced to improve students’ information literacy skills.

A design-intensive undergraduate engineering curriculum has been developed in a brand new, entirely laptop-based university around three core design courses, a program-specific capstone design course, and a design thesis.  Methodologies focused on assessing and evaluating the developed learning outcomes and the students’ ability to adequately combine design engineering project work with knowledge from coursework and integrate these with practical applications exist and are continually evolving.  However, these methodologies may still be improved.  In this research, a universally applicable methodical tool, developed in recent years, that is generally useful in knowledge evaluation exercises, was directly applied to the design engineering field.  Each component of the proposed model represents a different level of application starting from one’s basic understanding of a concept, the ability of one to relate knowledge and articulate relationships among elements of the fundamentals, and finally culminating into the ability of one to take knowledge and apply it to a novel situation.  Rubrics (charts describing learning at different levels of development) were developed to evaluate students’ level of knowledge application for the three core design courses and the capstone course.  The results of this study proved that the model is quite useful in evaluating the learning process of students via design projects and methods can be developed to customize and maximize its use.  

In this paper, the radial Schrödinger equation for central Coulomb potential using numerical Runge-Kutta has been solved. Energy eigenvalues for hydrogen and positronium bound systems is derived - 13.6056 eV and – 6.803 eV, respectively. Numerical results of ground state modes of wave functions for hydrogen and positronium R(r) and the presence probability function  has been presented. These results are in good agreement with analytical calculations of the hydrogen atom in modern physics and quantum mechanics. Therefore, numerical methods can be very useful and effective in solving physical problems.

Electricity is central to the existence of human being such that a country’s electric power generating capacity is equated with its level of development. Several Nigerians have lost their lives from inhaling (fuel type electric) generator fumes due to the inability of the federal government to provide stable electric power. Scientists and engineers have suggested the use of power inverters as the alternative to the fuel type electric generators. An inverter is an electronic device that has the ability to convert the direct current, dc, from the battery or solar cells (panels) to alternating current, ac, which is the convectional form that powers many electrical appliances. Many inverters ranging from low wattages to high wattages are now found in homes and offices across Nigeria. Majority of these inverters can not be used to adequately power some electrical appliances due to the poor design techniques employed by the designers. This paper discussed the main building blocks of the power inverters: the oscillators and the power amplifiers design techniques. The merits and demerits of various design techniques available for the development of different types of power inverters were spell out.

The transition temperature of the gap functions of two irreducible representations are very close to each other, but it is not possible to consider them independently. We have to extend the Ginsburg-landau free energy to both representations, including also coupling terms between the order parameters

The global positioning system (GPS) was used to measure the longitudes, latitudes and elevations above mean sea level at eight (8) locations evenly spread within the major communities in Emu and Ogume kingdom. The water elevation contour map of the study area revealed that groundwater flow toward the South and South eastern part of Emu and Ogume kingdoms. Based on the flow pattern of the aquifer system in Emu and Ogume Kingdoms, dumpsites should be sited in the south and southeastern part of the area, and not in the north, west and eastern region. This was to minimize groundwater contamination.  This research informed the people of Emu and Ogume kingdoms on the possible areas dumpsites could be sited in order to reduce groundwater contamination. it also recommended that boreholes for potable water supply be sited in the North, West and eastern parts of the communities and not within the south and southeastern parts.

The execution of water borehole project is expensive; there is therefore the need for surface resistivity measurements before drilling. Vertical Electrical Sounding (VES) using Schlumberger configuration is one of the most reliable geophysical techniques and was carried out in Ndokwa land to obtain and document not only the layers of the near surface aquifer but to determine the thickness and depth to the aquifer and hence recommend the area/s boreholes could be drilled for potable and sustainable water supply.

A total of 569 vertical electrical soundings data were obtained from 36 locations evenly spread and spaced 2 km apart using the Schlumberger array method. The apparent resistivity values obtained in the field were plotted against half current electrode spacing in a log-log graph. The resulting curves were interpreted both qualitatively by inspection and quantitatively by matching small segments of the field curves using two-layer model and their corresponding auxiliary curves. The resistivity and thickness obtained from the partial curve matching were improved upon by employing an iterative computer program to obtain the layer parameters. The type of curves, the resistivity of the sediments and the knowledge of the local geology of Ndokwa land were used as guides in the analysis and interpretation of the layer parameter in terms of probable and sustainable water supply.

In Ndokwa land, 2 – 4 layers of aquifer were identified within the third and the fourth geoelectric layers of the earth. These layers consists of the medium to coarse grained sand formations of resistivity values ranging from 300 Ωm to 1500 Ωm with an average thickness of 35 m, Boreholes for potable and sustainable water supply is therefore recommended at a depth of between 30 m and 45 m in Ndokwa land.

Three samples of Carica papaya leaves (Green, Yellow and Brown) were collected randomly from Ogbomoso town, Oyo state, Nigeria and analyzed for the phytochemical composition, vitamins and mineral constituents. Phytochemical screening revealed the presence of bioactive compound saponins, cardiac glycoside alkaloids and absence of tannins in the three samples.

Results showed that the plant leaves contained the vitamins, (mg/100g), thiamine (B₁): green leaves 0.94, yellow leaves 0.41, brown leaves 0.52; riboflavin (B₂): green leaves 0.13, yellow leaves 0.04, brown leaves 0.06; ascorbic acid (C): green leaves 16.29, yellow green 9.62, brown leaves 11.26. Mineral analysis showed highest values (mg/kg) of Ca, 8612.50; Mg, 67.75; Na, 1782.00; K, 2889.00; Mn,9.50  in the green leaves, and Fe, 147.50 in yellow  leaves as compared to other elements examined. Thus green pawpaw leaf gave a source of essential nutrients while yellow pawpaw was a source of iron. Therefore pawpaw leaves can be manipulated in the herbal treatment of various diseases and as a potential source of useful elements for drugs formulation.