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Nanostructured surfaces are surfaces bearing nano-sized features that have characteristic lengths ranging on a scale of a few to a few hundreds of nanometres. Nanostructuration of surfaces is considered as a promising track in many micro-thermo-fluidic applications, as it is expected to allow noticeable heat transfer enhancement or hydraulic resistance reductionis due to momentum transfer to the solid walls. This paper reviews and summaries the recent experimental and theoretical works on the pool boiling with nanostructure surfaces

Pre-treatment effects on the quality of oven –dried peeled and unpeeled ginger, grown locally form Kadjebi in the Volta Region of Ghana was evaluated by determining proximate and phytochemical content using conventionally accepted methods. The pre-drying treatments under investigation were dipping in 10% citric acid solution, dipping in 10% ascorbic acid solution, dipping in 10% sodium chloride solution and a control. The pre-treatments resulted in varied results in the pH, protein, vitamin C and TTA readings. The vitamin C content of the treated peeled and unpeeled samples, with ascorbic acid scored the highest value of 0.54±0.01mg/100ml for peeled and 0.95±0.01 mg/100ml for unpeeled ginger. No significant difference was observed between the control of both peeled and unpeeled samples with respect to the protein content. However, there were significant differences in the treated peeled and unpeeled ginger samples. Peeled ginger, pre-treated with citric acid recorded the highest protein value of 9.63±0.11%. Unpeeled ginger samples exhibited higher antioxidant components than peeled ginger samples.

The purpose of the study was to prepare spherical agglomerates (SA) of Tolfenamic acid (TA) by solvent change method. Crystallization medium used for spherical agglomerates of Tolfenamic acid consisted of N,N-dimethylformamide (DMF), Water and chloroform. The presence of solvents residuals in SA was determined by Gas chromatography and particles were characterized by DSC, FT-IR, XRD and SEM. The respective solubility study and dissolution behavior studies were carried out. The samples were stored in stability chamber to investigate their physical stabilities. Residual Solvents in SAs were found to be within the limit and exhibited decreased crystallinity as well solubility and dissolution of the spherical agglomerates was improved than commercial sample of Tolfenamic acid. In stability study, it was found that physical properties and release profile of the spherical agglomeration was unaffected for 6 months. Hence this technique can be used to obtain modified drug raw material for formulation of tablets of Tolfenamic acid by direct compression with directly compressible tablet excipients.

To satisfy the ever increasing network capacity, cellular systems should operate effectively with good grade of service (GoS) and quality of service (QoS). This paper proposes a quantitative approach to measuring the GoS and QoS performance of CDMA systems. It studies a realistic CDMA system operating in Nigeria and obtains empirical data from the field. A multi-dimensional Markov chain model is derived using related parameters and simulated under ideal conditions. The performance metrics of interest include blocking probability, handoff failure probability and weighted cost for GoS, and loss of communication quality for QoS. Simulation results show that effective link adaptation policies can greatly improve the system’s performance.

The development of the field was considered by running the cashflow analysis and establishing the economic indications. The one-well scenario was only able to produce 50% of EUR (2.8MMbbl) while the two-well scenario gave up to 80% EUR (4.7MMbbl) before abandonment rate for a field life of about 15 years. The cashflow analysis showed an attractive marginal project with positive Net Present Value for the $50/bbl base oil price scenario and the contractor’s take was estimated to be about 22% of the total share. The greatest effect on the NPV was seen from the Petroleum Profit Tax and the oil price in the sensitivity analysis which is negative and positive respectively. OWA marginal field reflects a typical low reserve development category and with effective cost management even at extreme low crude oil prices, a marginal profit can be ascertained and eventually fostering the Nigeria economy.

Surface finish is very important criteria in Industry for quality of the product. For obtaining the desired surface finish, process parameters of machining process turning, have to be optimized. Up to now industries are dependent on Handbook data, for determining the parameters, but using Taguchi method & Response surface method, optimized data can be obtained by preparing the model, and validation of that model is done by the experiments. In the present paper, review of such effort is taken into account. This is a short review of researchers work for optimizing the process parameters using speed, feed, depth of cut, nose radius, various coating on tool, and tool geometry as input parameters and output parameter as surface roughness, tool wear, Material removal rate etc.

The present study was aimed to analyze the relationship between occupational stress and organization citizenship behavior of academic staff working in Higher Education Institutions of Pakistan. Qualitative and quantitative approaches have been used to explore the relationship of occupational stress and organization citizenship behavior by using a sample of 240 academic staff of public sector institutions of higher education located in Islamabad, Pakistan. Data were collected through personal visit to the offices of academic staff. Two research instruments i.e. Occupational Stress Inventory–revised (OSI-R) and OCB inventory by Podsakolf and Mackenzie were used to collect data. For data analysis Pearson Correlation was applied. Data analysis revealed that significant negative relationship was found in responses of academic staff regarding occupational stress and organization citizenship behavior.

Economic growth is the core power to promote and shape the urbanization development, which helps to promote the economic development and social progress in ethnic regions of China Ecological civilization focuses on improving the relationship and ending the confrontation, separation, mutual exclusion and conflict between man and nature, ethnic regions of China should promote the construction of ecological civilization from multiple aspects and realize sustainable development. Xinjiang Uygur Autonomous Region is one of five ethnic regions of China; the urbanization in Xinjiang is unique in its functions, layout, dynamic mechanism, realizing path, and system background. Thus, it is necessary to select different paths according to different local conditions, to achieve multiple functions of economic development, ecological security and social stability.

In this paper, we proposed the development of neural adaptive controls to ensure the robustness of uncertain nonlinear multivariable systems. We used two techniques: Robust neural adaptive control and neural indirect adaptive control. The study of the stability and robustness of both techniques was performed by Lyapunov theory. To validate these techniques and discover their effectiveness, a simulation example was considered. The simulation results obtained by these two control techniques have shown the effects of disturbance compensation, good performance tracking data paths and stability control systems. Comparative studies between these two techniques show that the neural indirect adaptive control cannot mitigate the effect of disturbances compared to the robust neural adaptive control.

Image cryptography and Steganography has attracted extensive research on the security of message that is to be transmitted in the open insecure medium. This is due to the fact that huge amounts of data can be hidden without perceptible impact to the carriers and possibly because of the popularity of electronic images and medical images that have become widely available. The chaotic based secret writing has its own advantage and it is mainly based on the initial condition which is the secret key for the secret writing. The chaotic based encryption serves as the robust mechanism against all sorts of attacks. In this paper, a novel image encryption and decryption scheme is proposed. Due to sensitivity to initial conditions, chaotic maps have a good potential for designing dynamic permutation map. Here a chaotic Henon map is used to generate permutation signal. Simulation results illustrate that the scheme is highly key sensitive and shows a good resistance against brute-force and statistical attacks.