The effects of dual-fuel on improving the ballistic efficiency of a low energy sugar-based solid rocket propellant were investigated in this paper. This was achieved by establishing a threshold proportion of sucrose to sorbitol that provided the highest ballistic efficiency, using a beam load cell (model single-point 2,000 kg linearly defined by 0-20 kN force, with ±.005 percent precision). Seven different propellant formulations were prepared, loaded into the rocket motor and tested for performance. The major performance parameters of interest were the thrust, total impulse, burn time, delivered specific impulse, delivered characteristic velocity, and the chamber pressure. The formulations tested were potassium nitrate–sucrose propellant (65% KNO3 and 35% sucrose (C12H22O11)) (KNSU); potassium nitrate-sorbitol propellant (65% KNO3 and 35% sorbitol (C6H14O6)) (KNSB); modified potassium nitrate-sucrose propellant (65% KNO3, 32% sucrose (C12H22O11)), and 3% carbon (C) (MODKNSU); potassium nitrate-sucrose-sorbitol propellant (65% KNO3, 25% sucrose (C12H22O11)), and 10% sorbitol (C6H14O6) (KNERK); potassium nitrate-sucrose-sorbitol-carbon propellant (65% KNO3, 24% sucrose (C12H22O11), 10% sorbitol (C6H14O6), and 1% carbon (C)) (MODKNERK); and finally a propellant made from KNO3, sucrose (C12H22O11), sorbitol (C6H14O6), carbon (C) and iron II oxide(Fe2O3) combinations in 65, 30, 3, 1, 1% proportion respectively. The novel result obtained from these experiments was applied to boost the performance of a KNSB rocket propellant motor during a rocket launch experiment. Both static and dynamic rocket motor internal ballistic parameters were then compared. The measured delivered motor average thrust and the effective propellant burn times were recorded as: (164.15N, 3.97s); (102.95N, 6.53s); (65.66N, 9.38s); (79.09N, 3.77s); (243.98N, 3.77s) and (92.6N, 5.89s) respectively. The MODKNERK, was established to produce a most efficient motor and with the full delivery of its ballistic energy. It was also established, that the ballistic and rocket motor efficiency of a lower energy rocket motor can be improved by starting the ignition of such motor with fast burning dual-fuel rocket propellant (MODKNERK).
Target tracking is a process that may find applications in different domains such as video surveillance, robot navigation and human computer interaction. In this work we have considered the problem of tracking a moving object in a multi agent environment. The environment is a rectangular space bounded by walls. The first agent is the target and it moves randomly in the space. The second agent should follow the target, keeping as close as possible without crashing with it. It uses sensors to detect the position of the target. The sensor readings give the distance and the angle from the target. We use reinforcement learning to train the tracker to detect any change in the movement of the target and stay within a certain range from it. Reinforcement learning is a form of machine learning in which the agent learns by interacting with the environment. By doing so, for each action taken, the agent receives a reward from the environment, which is used to determine positive or negative behaviour. The goal of the agent is to maximise the total reward received during the interaction. This form of machine learning has applications in different areas, such as: game solving with the most known game being AlphaGO; robotics, for design of hard-to engineer behaviours; traffic light control, personalized recommendations, etc. The sensor readings may have continuous values, making a very large state space. We approximate the value function using neural networks and use different reward functions for learning the best policy.
The study was carried out on the physico-mechanical properties of plaster of Paris (Gypsum plaster) reinforced with paper pulp in order to improve the weight of plaster paste and to obtain materials of lighter weight that solve problems such as poor flexural strength, and crack propagation. To do this experiment, the considerable basis of a standard of 2 kg of plaster of Paris was taken as the test sample. Gradually plaster of Paris was substituted with paper pulp paste in a water basin in proportions K0, K1, K2, K3, K4, K5 and K6 representing the different percentages of 0%, 10%, 20%, 40%, 60%, 80%, 100% of mixture respectively. After the above observations, the following parameters on fresh and hardened samples were tested: the start time of reaction, and end time of hardening, consistency, the flexural and compressive strength, shrinkage, and apparent density. At the end of these tests, it was determined that, the incorporation of small amounts of paper pulp (2 kg samples) into the plaster paste improves its flexural properties. But from k0 to k6, properties related to bending and compression began to gradually fall which is a consequence of the augmentation of the amount of paper paste in the plaster paste. The presence of paper pulp in the plaster of Paris paste increases the time of hardening of the plaster cement from one proportion to another, reduces the workability of the mixed paste, significantly solves the problem of removal, the apparent density drops when waste paper paste is increased in the mixed plaster. Because of its light weight, low density, its acceptable Mechanical properties, these new materials are recommended for exploitation in the manufacturing of popular lightweight construction finishing like panels for ceiling or walls, staff works and other applications.
This study considered a newly proposed Exponentiated Complementary Mukherjee-Islam distribution obtained by exponentiating the Complementary Mukherjee-Islam distribution. Some properties of the new distribution were derived and results from the distribution indicated that the distribution is a better alternative than its baseline distribution. The new distribution is therefore a creditable addition to the existing family of exponentiated distributions.
During drilling operations, it is essential to keep the wellbore pressure within the maximum value of the fracture pressure and minimum value of the pore pressure of the formation. To handle this challenge, the fracture pressure of the formation must be known as it is significant to determining the mud window design. This study developed a correlation that could predict the formation fracture pressure in the Niger Delta deep offshore field. Two different fields were considered for this model named Field 1 and 2. From these fields, fracture pressure data were gotten from 21 wells during leak off test (LOT) at different casing shoe depths. While carrying-out the analysis of data, assumptions were made that the formations throughout the Niger Delta basin obeys the principle of horizontality. Also, that the fracture pressure at same depth is uniform with the pressure at other location in the Delta. Scatter plot was used as the tool for the data analysis. A line of best fit was drawn to arrive at the correlation. This correlation has an R2 coefficient values of 0.9969. In conclusion, the correlation gotten from this study for predicting fracture pressure has shown to align with some data sets from the Niger Delta fields with very little variation. This can be used for planning of further drilling operations in the Niger Delta to make it easier, faster and more economical.
A shell-and-tube heat exchanger which was subjected to different flow configurations, viz. counter flow, and parallel flow, was investigated. Each of the flow configurations was operated under two different conditions of the shell, that is, an uninsulated shell and a shell insulated with fiber glass. The hot water inlet temperature of the tube was reduced gradually from 60 oC to 40 oC, and performance evaluation of the heat exchanger was carried out. It was found that for the uninsulated shell, the heat transfer effectiveness for hot water inlet temperature of 60, 55, 50, 45, and 40 oC are 0.243, 0.244, 0.240, 0.240, and 0.247, respectively, for the parallel flow arrangement. For the counter flow arrangement, the heat transfer effectiveness for the uninsulated shell are 2.40, 2.74, 5.00, 4.17, and 2.70%, respectively, higher than those for the parallel flow. The heat exchanger’s heat transfer effectiveness with fiber-glass-insulated shell for the parallel flow condition with tube hot water inlet temperatures of 60, 55, 50, 45, and 40 oC are 0.223, 0.226, 0.220, 0.225, and 0.227, respectively, whereas the counter flow condition has its heat transfer effectiveness increased by 1.28, 1.47, 1.82, 1.11, and 1.18%, respectively, over those of the parallel flow.
The effect of Carbon Fiber Reinforced Polymer (CFRP) retrofitting and concrete type on the flexural strength of prestressed concrete I-section girders used in bridges and beams in buildings is investigated. Non-linear moment-curvature relationships are predicted using an iterative algorithm for both non-retrofitted and CFRP-retrofitted prestressed concrete girder and beam cross-sections with various concrete types. Two different CFRP-retrofitting schemes are analyzed for comparing their effectiveness. It is found that although non-retrofitted beam section exhibits greater ductility, the use of CFRP retrofitting in both tension and compression regions simultaneously results in a significant increase in flexural strength. It is also found that the higher the ultimate concrete strength, the higher is the influence of CFRP-retrofitting on increasing flexural strength.
The study has evaluated production performance of oil well by using nodal analysis for entire production system. The goal of this study is to analysis one of the Sudanese oil field using nodal analysis and to review the field completion strategy for the respective field. The study starts by collecting the data from oil Company and takes the X Field as case study. The X field consist of 18 well and four of them were selected for theanalysis namely X NW-1, X NW-2, X NW-3 and X NW-4. Operating pressure for each well are 2409, 2455, 2550 and 2420 psia, and operating flow rate are 3925.4, 1110.4, 2255.7, and 1387.2 STB/D respectively. Wellfl modeling used for this task, which permits the production optimization of oil well using the concept of nodal analysis. Several sensitivity analyses were conducted in order to get the production forecast. If assumed thatthe depletion in the pressure occur within 1 year, the pressure reduced to 2000 and 1000psia for each well; as can be seen, the production reduced rapidly inXNW-2 and XNW-4. However, 1000psia the production becomes zero for the four wells.
This study was conducted to investigate physicochemical properties, copper corrosion test and test the diesel engine performance of diethyl ether diesel blend fuel. With aid of distillation characteristic, the blends percentage were selected as DEE5%, DEE10, DEE15 and DEE20%. Stabinger Viscometer apparatus was used to determine the Kinematic viscosities, Digital Density Analyzer was used to determine the densities. ASTM D 4737 – 03 Test Method are used to determined calculated Cetane index. Copper strip corrosion device was used to determine corrosiveness of copper from diesel and DEE diesel blends. A single cylinder, four stroke diesel engines, mounted on a moving frame was used to conduct the engine test. From the study result we found that that blends physicochemical properties improved with diethyl ether ratio increased in the blends. While Cetane Index increased with diethyl ether ratio increased. At the higher load, the best result of Break thermal efficiency found at DEE10%, where at the low load, the best mechanical efficiency found at DEE5%, DEE15% and DEE20 and at the higher load, the best mechanical efficiency found at DEE20%, on other hand at the low load, the best specific fuel consumption found at DEE15%, While at the higher load the best specific fuel consumption found at DEE10%. Due to availability of diethyl ether in Sudan, diethyl ether can be used up to 10% in diesel blend with no further changed in diesel engine design, and this can be contributed to overcome the diesel fuel crisis in Sudan, but further information and studies are needed for diethyl ether transportation and blending facilities, beside study the effect the addition of diethyl ether on diesel price.
Together with globalization, factories, companies and even countries can survive by competing with their rivals. Nowadays, technological superiority is one of the most important factors determining competitive power. This situation causes the result of rapid change and development of technology. Due to improvement in technology, humanity dependence on electricity is increasing day by day. Many new devices get in our lives, and both the continuity and quality of electricity comes across as an important issue. Different researches are carried out to make the energy more qualified and efficient. In terms of the stability of the used electrical devices, it is important to keep the harmonic amount in electrical energy under a certain value. Besides this, these unwanted harmonics cause additional energy losses in the energy system and negatively affect energy efficiency, which is an economically important problem. In this exercise, the problems in electrical systems, the damages in electrical devices caused by harmonics have been researched and various solution suggestions have been developed for this problem.
In this work, an investigation was carried out on the effect of ultraviolet light on different films. Polystyrene (PS), poly (caprolactone) (PCL), and blended films of PS/PCL were produced. Ethyl acetate (AE) was used as a solvent, and PS and PCL solutions were prepared by dissolving 250 mg in 2.5mL of AE under mechanical stirring at room temperature. The blended solutions of PS/PCL (PS:PCL) were prepared with different mass proportions, such as 90:10, 80:20, 70:30, and 60:40 into 2.5 mL of EA. The solutions were dripped with 500 µL on a glass substrate, and the films were produced with mechanical rotation of N=2000 RPM for 15 seconds using a Spin coater. The films were submitted to ultraviolet light for t=60 minutes and morphologically analyzed by optical microscopy, chemically by IR spectroscopy, and superficially by contact angle and wettability; this last analysis also investigated the effect of ultraviolet light at t=0, t=30, and t=60 minutes. The exposure of ultraviolet light on the films affected its morphologies. IR spectra showed that the photodegradation increased for larger PCL amounts into the blend. The contact angle measurements showed that after exposure to ultraviolet light, the hydrophobicity of the films increased. Therefore, the presence of PCL in the polymer mixture promoted the photodegradation of the PS/PCL films, making it attractive for developing new packaging.
This study examined the performance of the ARIMA, ARIMAX and the Single Exponential Smoothing (SES) model for the estimation of diabetes cases in Anambra State with the following specific objectives: to fit the model to the data, to determine the best fit model for estimating diabetes mellitus cases and forecast for expected cases for period of five years. The secondary data used for the study is sourced from records of Anambra state Ministry of Health. The Akaike information criterion is adopted for assessing the performance of the models. The R-software is employed for the analysis of data. The results obtained showed that the data satisfied normality and stationarity requirements. The finding of the study showed that ARIMA model has least value of AIC of 1177.92, following the ARIMAX model with value of AIC=1542.25 and SEM recorded highest value of 1595.67. The findings further revealed that the ARIMA has the least values across the measures of accuracy. More so, five years predictions of the cases of diabetes mellitus were obtained using the models under study. From the results of the findings, ARIMA model proved to be best alternative for estimating reported cases of diabetes mellitus in Anambra state. Based on the findings, we recommend there is need for medical practitioners /health planners to create awareness and inform patients about the possible related risk factors of death through early diagnosis and intervention.
The use of burnt-clay bricks is increasing in rural areas because of its availability and low cost. However, the burning of bricks locally at unknown temperatures will likely result in the production of bricks that are unfit for construction purposes. The study assesses the minimum number of days bricks require to attain the minimum stipulated standards for compressive strength and water absorption. The results obtained were compared to the NIS 87: 2000 standards to assess their conformity. From the study results, the mean compressive strength of bricks (1.576 N/mm², 2.306 N/mm², 3.634 N/mm²) at 48, 72 and 96 hours of firing fails to attain the target value of 5N/mm² as stipulated by the NIS building code. However, the mean compressive strength after 120 hours (5.386 N/mm²) attains the stipulated unit value. The water absorption rate displayed similar findings with mean values of 37.12%, 34.2%, 28.88% failing to conform with the stipulated 20% standards. However, the mean of water absorption after 120 hours (21.02%) has no significant difference and hence conforms to the stipulated value. This therefore means that bricks should be burnt far beyond the 120 hours in order to safely conform to 5N/mm² and 20% compressive strength and water absorption respectively.
the key goal of this article is on the design and optimum sliding mode control for Grid-Connected direct drive extraction method of ocean wave energy by Multi-Objective Particle Swarm Optimization (MOPSO). A Linear Permanent Magnet Generator simulates the ocean wave energy extraction system, driven by an Archimedes Wave Swing. Uncontrolled three-phase rectifiers, a three-level buck-boost converter and 3 level neutral point clamped inverter are planned grid integration of Wave Energy Conversion device. The technique monitors the three-level buck-boost converter service cycle linked to the PMLG output terminals and decides the optimum switching sequence of 3 level neutral point clamped inverter to enable the grid relation. Simulations using Matlab/Simulink were carried out to test working of the wave energy converter after the suggested optimal control method was applied under various operating settings. Various simulation test results indicate that the proposed optimum control system is tested in both normal and irregular ocean waves. And it has been shown that the control method of the MOPSO sliding mode is ideal for maximizing energy transfer efficiency. Better voltage management at the DC-link and for achieving greater controllability spectrum was accomplished by the proposed Duty-ratio optimal control system.
The rising climatic degradation due to the emission of greenhouse gases is leading to emergence of clean combustion technology, oxy-fuel combustion to minimize the emissions of carbon dioxide into the atmosphere in combustion. Nitrogen molecules are used as probe molecule in laser-based combustion diagnostic in nitrogen rich air combustion. However, with the introduction of oxy-fuel combustion, carbon dioxide becomes the dominant molecule and has to be considered as probe molecule in combustion diagnostic. A detailed knowledge about thermodynamic properties: temperature, pressure and species concentration are necessary in optimization of combustion and minimizing the emission into the atmosphere. The non-intrusive spectroscopic measurement techniques are the most accurate methods to determine the combustion properties. The purpose of this review is to provide a brief overview of the recent advances made in application of coherent anti-Stokes Raman scattering of carbon dioxide for development of models for thermometry. However, there is no sufficient empirical data of time-domain S-branch Raman linewidth dependence on temperature that has been determined for pure-rotational coherent anti-Stokes Raman scattering of carbon dioxide and its mixtures for development of models for thermometry.
As fat contributes important textural properties such as lubricity and tenderness to cakes, it is plausible to focus on ways to increase the perception of these properties with the aim of creating the illusion of a higher fat. The utilisation of small sugar particles has been shown to increase the moist and soft texture of Chocolate Brownies. The present study assessed three different sugar particle sizes in their ability to create the illusion of fat content and therefore their ability to permit fat replacement (FR) in this product. The unground commercial sugar (200-5181 µm) was used as the control (UC) and two of its sieved sugar separates, Large (L924-1877 µm) and Small (S459-972 µm) were investigated. For each, fat was replaced using pureed black beans. The most accepted sample was used for sucrose replacement (SR) using inulin and Rebaudioside A. (Reb A.). Samples containing the smallest sugar fraction with 25% FR were most significantly associated overall acceptability (OA) (p<0.01). The application of small sugar particles did not significantly negatively affect OA or liking of samples at a level of 75% FR compared to the other two sugar fractions. The utilisation of small sugar particles (459-972 µm) in the preparation of baked goods could aid baking & industry professionals in reducing the fat content of cake-like products.
YAMUGAG-20 Exploder is a Radio Frequency (RF)-based wireless exploder system designed and constructed specially for the Nigerian Air Force (NAF) to overcome the challenges associated with the existing wired exploders used for the disposal of unserviceable ordnances. The Exploder system has three main parts namely, the master transmitter unit, the master receiver/slave transmitter unit, and the slave receiver unit. Each of these units is made up of transceiver module, microcomputer and power source. The microcomputers were programmed using C and C++ programming language of the Integrated Development Environment (IDE) software. The exploder is portable and easy to operate. For a typical demolition exercise, the operation of the exploder is such that signals are relayed from the master transmitter unit to the master receiver/slave transmitter unit onto the slave receiver unit to initiate an electric detonator leading to the detonation of the unserviceable ordnances. Functionality, range, power consumption, and system reliability tests were conducted on the exploder to establish its performance and efficiency. The results obtained from the tests indicated that the exploder transmitting at a frequency of 2.4GHz performed satisfactorily up to a range of 1000 meters. Therefore, the exploder has the potential of not only meeting the demolition demands of the NAF but can also be applied for other nonmilitary purposes like mining and related activities.
The selection of optimum probabilistic model of extreme floods as a crucial step for flood frequency analysis has remained a formidable challenge for the scientific and engineering communities to address. Presently, there is no scientific consensus about the choice of probability distribution model that would accurately simulate flood discharges at a particular location or region. In practice, several probability distributions are evaluated, and the optimum distribution is then used to establish the design quantile - probability relationship. This paper presents the evaluation of five probability distributions models; Gumbel (EV1), 2-parameter lognormal (LN2), log Pearson type III (LP3), Pearson type III(PR3), and Generalized Extreme Value (GEV) using the method of moments (MoM) for parameter estimation and annual maximum series of four hydrological stations in Benue River Basin in Nigeria. Additionally, Q-Q plots were used to compliment the selection process. The choice of optimum probability distribution model was based on five statistical goodness – of – fit measures; modified index of agreement (Dmod), relative root mean square error (RRMSE), Nash – Sutcliffe efficiency (NSE), Percent bias (PBIAS), ratio of RMSE and standard deviation of the measurement (RSR). Goodness – of – fit assessment reveals that GEV is the best – fit distribution, seconded by PR3 and thirdly, LP3. In comparison with WMO (1989) survey of countries on distribution types currently in use for frequency analysis of extremes of floods shows that GEV is standard in one country, while PR3 is a standard in 7 countries, and LP3 is standard in 7 countries. It is recommended that GEV, PR3 and LP3 should be considered in the final selection of optimum probability distribution model in Nigeria.
The menace of environmental dilapidation has been an issue of great concern in the built environment since the wake of the industrial revolution. Buildings have been said to be instruments that cut short the natural cycles of resources in both the human and natural ecosystem due to man’s anthropocentric mind-set and activities. Various theories, framework, and models have been proposed to facilitate re-generatively sustainable developments. This paper aims at highlighting strategies that are currently practiced in regenerative development with a view of presenting ideas for the practical application of regenerative sustainability in all its facets and phases. Relevant literature that described the processes of creating a regenerative development and the aspects in which regenerative sustainability principles are implemented were reviewed. The design strategies employed in the studied cases were described as they related to the phases and then grouped into the four facets of regenerative development. The paper, therefore, gives an idea of the various integrative element and practical strategies for the implementation of regenerative design in all its phases and facets. Clarity on the subject of regenerative development is also anticipated as examples of regenerative design element implemented in the cases under study were detailed out. These strategies, when applied with attention to place patterns and potentials in all aspects of the built environment, will help in creating a truly regenerative development in any area.
In nature all of the heavy elements are produced by nuclear fusion reactions, mostly in supernova explosions and neutron star collisions, so, this is to date the only known and proven mechanism to produce heavy elements in usable quantities. In this work we approach a difficult challenge, namely, the possibility of fusion of heavy elements, taking as a test case the heaviest observationally stable element - ²³⁸U, showing that it is feasible, at least in principle with the help of existing technologies. The main idea behind is to show that fusion of lighter - than z=184 - nuclei is conceptually viable examining the tunnel effect assisted by an auxiliary field that will produce a Sauter like effect, and this is the pathway to explore the synthesis of elements higher than z=118. The production of theoretical untested elements like Unoctquadium-184 or close Z species could open a new chapter in the physics of super-heavy elements, and leads to a deeper understanding of nuclear decay channels and stability conditions. Nuclear fusion of heavy elements will open the breach to produce neutron rich elements, so we may obtain a deep insight into the physics of the island of stability. This work will review basic aspects of fusion physics related to the assisted fusion mechanism. An enhanced fusion perspective is found generalizing the work of [1] to space dependent fields and the cases of ²H, ¹⁰⁶Pd and ²³⁸U are presented for several test fields. A final section reviewing laser confinement fusion actual experiments capable of achieving the required energies is also reported.
