Engineering Commons^™

Behavior Of Square And L-Shaped Slender Reinforced Concrete Columns Under Combined Biaxial Bending And Axial Compression, Wen Hu Tsao

Dissertations

A numerical analysis was developed to evaluate the complete load-deflection and moment-curvature relationships for square and L-shaped slender reinforced concrete columns subjected to biaxial bending and axial load. This computer model can be used for any cross section geometry and material properties of normal concrete. The analysis was based on a deformation control and both the ascending and descending branches of curves can be studied. The finite difference method was introduced to calculate the deflections which satisfy the compatibility equations. Six square slender columns and eight L-shaped slender columns were tested to compare their experimental load-deformation results with the analytical …

A Generalized, Parametric Pr-Qmf/Wavelet Transform Design Approach For Multiresolution Signal Decomposition, Hakan Caglar

Dissertations

This dissertation aims to emphasize the interrelations and the linkages of the theories of discrete-time filter banks and wavelet transforms. It is shown that the Binomial-QMF banks are identical to the interscale coefficients or filters of the compactly supported orthonormal wavelet transform bases proposed by Daubechies.

A generalized, parametric, smooth 2-band PR-QMF design approach based on Bernstein polynomial approximation is developed. It is found that the most regular compact support orthonormal wavelet filters, coiflet filters are only the special cases of the proposed filter bank design technique.

A new objective performance measure called Non-aliasing Energy Ratio(NER) is developed. Its merits …

Implementing Computer Numerical Control Machine Tools In A Job Shop Environment, Rajesh Shah

Theses

Computer Numerical Control is one important phase to overall application of computer on the shopfloor. Today a large variety of CNC machine tools are offered by manufacturer following different standards. This thesis is organized with the purpose of comparing various technical and economical considerations for CNC machine tool purchase and application. The main purpose of study is to mention various features of CNC machine tools and its possible integration which can reduce product lead time and improve quality. General replacement minimum cost model is discussed with case study for economic justification of machine purchase. While discussing technical features emphasis is …

Parking Demand And Supply In The Central Business District Of Dar Es Salaam City, Theophil Rwebangira

Tanzania Journal of Engineering and Technology (TJET)

The Central Business District (CBD) Of Dar es Salaam city is currently experiencing severe congestion. Among the major causes of this condition is lack cf enough parking facilities. Obstructions due to vehicles parked on the roadway and increased vehicle circulation by drivers looking for a mace to park This paper reports on a recent study are major contributors to congestion. which evaluated the demand and supply as vell as usage of parking spaces in the CED. The f indings indicate that there is currently an acute shortage Of parking spaces, especially of off—street parking spaces. For the existing facilities, there …

Energy From Biomass: Combustion And Gasification, G John

Tanzania Journal of Engineering and Technology (TJET)

Some fundamental facts of the combustion Of BIOMAS are outlined and di scussed . It is suggested that these provide guidelines for rhe development Of successful practical combustors. Furthemore, a realisation Of energy conversion from the same in gasfier is presented.

Design, Operation And Maintenance Considerations Of Iiorizontal Flow Roughing Filters Preceding Slow Sand Filters, T Mbwette,

Tanzania Journal of Engineering and Technology (TJET)

The paper mentions some of the reported uses of Horizontal Flow Roughing Filters (IIRF) in drinking water treatment plants in Europe before briefly reviewing research activities carried out in the use of IIRF prior to Slow Sand Filters. Design, operation and maintenance aspects Of HRF are reviewed on the basis of the laboratory and field tests carried out in Tanzania and Switzerland, respectively in addition to experience gained in operation of a number of plants already built to date. Design aspects are introduced from the point of view Of its philosophy and optimization strategies before design guidelines are given. Important …

Flood Forecasting In Tanzanian Catchments, Omari Rumambo

Tanzania Journal of Engineering and Technology (TJET)

Floods are still a problem to many countries in the world todate. Floods do cause damages to property and sometimes loss to human life. Flood control measures by structural and non—structural methods are avail able in the literature . However , structural flood control measures are financially infeasible in most developing countries today. Flood forecasting is a non—structural measure for reducing flood damages. It is a means of providing early The Li near f 1 ood warnings to flood prone areas . Perturbation Model has been appl ied for real time flood The Linear forecasting in Tan zanian catchments . …

The Hydraulic Performance Of A Vortex Tube Foector, F Mtaro

Tanzania Journal of Engineering and Technology (TJET)

The vorle.r tube silt exrrac/or consists of a pipe, rhe crest of which has a slit and lies flush across lhe canal bed.With minimal warer loss, I.oe bedload is extracted through lhe slil settling canal back ro the river, thus reducing or eliminating the bedload transported in main canal. Ihe resulting swirling flow phenomena is of complex nature and depends on sc conirol paramerers, as a result of which previous empirical design approaches have yielded conflicting guidelines. By means Of a simplified hydraulic system, the flow mechanism and energy in rhe can be determined.

Absorption Of Nitrogen Oxides Into Sodium Hydroxide Solution In A Packed Column: Effect Of Gas Flowrate And Temperature, J Katima

Tanzania Journal of Engineering and Technology (TJET)

The effect of gas flow rate and temperature on the absorption rate of nitrogen oxides (NO ) and column absorption eff iciency has been studied using a 2M goåium hydroxide (NaOH) solution in a packed The absorpt ion process was carried out at atmospheric column. pressure, with NOV concentration ranging between 150 and 10000 pp:tt, NO/N02 ratio of O and 1 iquid flow rate of O .8 1/ min. The gas flow rate was varied from 20 to 60 1/17 in and the temperature from 25 to 45 c. It was found that Ehe column absorption efficiency increases with decreasing …

An Implementation Of Bionomial-Qmf For Subband Coding Of Speech, Feng Chen

Theses

A real-time subband speech codec is implemented by the author on TMS320C25 digital signal processor based hardware for speech compression down to 0.25 bit per sample.

The Binomial Quadrature Mirror Filters (B-QMFs) are employed as the basic block for the hierarchical, dynamic tree, analysis/synthesis filter bank. After the analysis, available bits are optimally allocated among subbands. Band statistics are updated to overcome the nonstationarities of speech signal.

The energy compaction performance of this codec is compared with different subband and DCT in simulations for speech signals and AR(1) source models.

It is shown that the speech codec implemented provides an …

Vision-Guided Servoing Robot Arm System, Shing Lee

Theses

This thesis investigate the problem of tracking 2-D circle parts with an eye-in-hand robot arm system. A vision module capable of measuring the motion of a circle is developed. Two algorithms based on the conic equation representation of circle and the symmetric property are developed. The first algorithm approximates the image of the circle as an ellipse. The second algorithm use the arc radius estimator to extract two image points of the circle located at the center of the largest arc. These image points are then used to solve for the inverse perspective transformation. An inverse kinematics solution based on …

Development Of Cellular Manufacturing Systems For Overall Production Efficiency, Srinivas Lokula

Theses

For years the industrial job shop is facing an increase in complexity and decline in productivity due to increase in parts mix, volume of parts, plant size, machine production rates and part complexity. The development of Group Technology and Cellular Manufacturing seeks to eliminate or minimize complexity and to maximize productivity.

Cellular manufacturing is the physical division of job shop's manufacturing machinery into production cells. Each cell is designed to produce parts requiring similar machinery and machine operations. Cellular manufacturing is one of the best manufacturing techniques to support Just In Time manufacturing and Total Quality Management.

This thesis work …

Handling Of Glass Mat Thermoplastic From Manufacturing Station To Heating Station To Molding Machine, Ramulu Srinivas Neela

Theses

GMT composite sheets are a family of continuous glass fiber roving impregnated with thermoplastic resin with parts formed by compression molding. Significance of GMT sheets comes by its cost-effective performance sufficient to penetrate automotive, industrial, construction, and other markets not willing to pay for higher cost, fiber-reinforced composite systems. GMTs in comparison to traditional sheet metals and sheet molding compounds (SMCs) are lighter, corrosion resistant, require no special storage, exhibit faster cycle times, require no chemical reaction, produce less scrap, possess recycling benefits, are ready for painting, and exhibit maximum opportunities for parts consolidation due to exceptional strength, formability, lower …

Study Of A Non-Contact Gaging System Of Inspection, Gordhanbhai Ketan Patel

Theses

The quality control function has traditionally been performed using manual inspection methods and statistical sampling procedures. Manual inspection is generally a time - consuming procedure which involves precise, yet monotonous work. It often requires that parts be removed from the vicinity of the production machines to a separate inspection area. This causes delays and often constitutes a bottleneck in the manufacturing schedule.

As a solution to the above problem a Non - Contact Gaging System developed by Optical Gaging Products, Inc., has been used here to study the feasibility of using an automated inspection system and a procedure of developing …

Realization Of High-Speed Carry Propagation For Addition And Multiplication Using The Redundant Binary System On The Mesh And Hypercube Connected Structures, Anil Rana

Theses

The extensive development of large-scale digital computers has naturally been accompanied by a corresponding development of techniques for fast arithmetic operations. Addition is the basis for the majority of the other arithmetic operations and most of the required time is due to carry propagation delay. Various algorithms have been proposed for fast addition and multiplication. The algorithms proposed here use the redundant binary system and are designed for the mesh structure. The algorithms are very efficient for the addition and multiplication of long operands. The algorithms can also be implemented on the hypercube. The n-dimensional hypercube is a highly concurrent …

Software Development For Analysis Of Stochastic Petri Nets Using Transfer Functions, Aman U. Jamwal

Theses

This thesis research is an implementation of a closed-form analytical technique for study, evaluation and analysis of Stochastic Petri Nets (SPN). The technique is based on a theorem that an isomorphism exists between an SPN and a Markov Chain. The procedure comprises five main steps: reachability graph generation of the underlying Petri net, transformation of the reachability graph to a state machine Petri net, calculation of transfer functions, computation of equivalent transfer functions via Mason's rule, and computation of performance parameters of the SPN model from the equivalent transfer functions and their derivatives. The software is developed in UNIX using …

The Stability And Sate Dimensioning Of Circular Masonry Arches, A Mrema

Tanzania Journal of Engineering and Technology (TJET)

An analysis of masonry arches where collapse is assumed to occur by the hinging of voussoirs upon each other is made. The behaviour of the arch material is assumed to be such that the plastic theory is valid. Certain aspects related to the properties So far the approach by of the line of thrust are clarif led. writers has been based on the conventional view that the 1 ine of It is shown that pressure is tangential to the line of thrust. this is not the case in general. Definitions are given on what is meant by "line of thrust" …

Nn Investigation Of Nitrogen Oxide Abscwption In Packed Columns, J Katima

Tanzania Journal of Engineering and Technology (TJET)

An experimental study was carried out on the performance of a packed column to study the absorption mechanism of nitrogen oxides (NOx). Two packed columns were set up, one with wall wiper rings to reduce wall effects and one without. Both columns were packed with stainless steel lessing rings and operated at fixed gas and liquid flow rates (40 and 8 L/min, respectively), atmospheric pressure, temperature (25°C), and sodium hydroxide concentration (8% w/w). The NOx (NO₂ and N₂O₄) equilibrium concentration and feed concentrations of up to 7000 ppm were used. The results indicated improved performance in the column with wall …

Nitrogen Oxides Rbsorption Into Sodium Hydroxide Solution In A Packed Column Column: Effect Of Naoh Concentration, J Katima

Tanzania Journal of Engineering and Technology (TJET)

Experiments have been conducted to evaluate the ettect of sodium hydroxide (NaOH) concentration upon the absorption rate of nitrogen oxides (NO ) and packed column performance. The absorption process using was carried out at atmospheric pressure and 29B K, concentrations between zero and w/ w, NO/ NO ratio of 0.5 and NO concentrations between 150 and 10000 ppm in an air mixture. The performance of the calumn was enhanced by the presence of hydroxyl ions ( 0B - ) relative to the absorption into water, however, The absorption it was found to be independent of NaOH concentration. rate of NO …

Carrying Capacity And Cracking Resistance At The Of Halving Joints In Reinforced Concrete Beams, S Mpinzire;

Tanzania Journal of Engineering and Technology (TJET)

Results are presented from tests on 3 beams having discont inuous support zones. All Of them had web and diagonal shear reinforcement. TWO out Of the three represented beams, their test results have been analysed in a paper designated part I which appeared in the Uhandisi Journal , Vol. I December 1989. They have been presented in this paper for compar ison purposes. The third beam has been made to invest i gate the effect of anchoring diagonal shear reinforcement by spot Welding method. The third beam was tested With two concentrated loads in the span. In all beams several …

A Finite Element Analysis Of Wood In Transverse Compression, A Mrema

Tanzania Journal of Engineering and Technology (TJET)

A two dimensional finite element analysis is utilized to predict the stress and strain distributions for wood in transverse compression. Important key var iables are incorporated into the ana lysis to define their influence on the stress and strain distributions. These variables are geometry of loading, geometry of specimen and the orthotropic ratio of the material. Based on the finite element analysis results, relationships are arising stress from developed relat ing maximum stress concentrations to the above three variables. possible appl ications of the results from this study relate to the development of more efficient design of connections such as …

Comparative Study Of Inlet Manifold Tuning To Enhance Supercharge, Mtui L

Tanzania Journal of Engineering and Technology (TJET)

Computer model ing and experimental results on a single cylinder, four-stroke cycle engine for best air flow characteristic is The modeling analysis is based on hornet ropie fluid di scussed . The model n g resul s is flow w it. h constant: specific heats. included to val idat.e the s imulation program against experimental results with widely vary ing manifold lengths and engine speeds. ExperimenLal results are obtained by measuring air f low rates Lo the inlet valve during steady g Late speed Of Lhe engine. Manifold tuned lengths are Obtained for a range Of speeds by exper and …

Experimental Investigations On The Behaviour Of Wood In Transverse Compression, A Mrema

Tanzania Journal of Engineering and Technology (TJET)

Experimental investigations were done to study the behaviour of wood in transverse compress ion. Three key variables were incorporated in the experiments to study their influence on the •nriables were the orthotropic ratio of the behav iour. These material, the geometry of loading and that of the specimen . Deformation measurements were made at selected locations on test specimens by means of strain—gage based clip gages. Results from the experimental measurements were compared to previous deformation predictions made by a finite element analysis (9) . There is a very good agreement between measured values and those obtained trom the finite …

Density Measurement For Corrosive Solutions At Elevated Temperatures, Kimweri, H

Tanzania Journal of Engineering and Technology (TJET)

In this work, apparatus for measuring densities of corrosive solutions at high temperatures was developed and used. Densities of dilute aqueous sulphuric acid solutions, containing different amounts of zinc and iron salts were measured at temperatures up to 185°C. In view of the good agreement between consecutive measurements for each solution and the density of water obtained by using this apparatus with that given in literature, for all experiments, the apparatus is recommended to be used for measuring densities of corrosive solutions at high temperatures.

Electrical Equivalent Method For The Calculation Of Vibrations In Transformers, D Chambega

Tanzania Journal of Engineering and Technology (TJET)

Noiselevel calculations may be done using an electrical equivalent method. So far a single mass and a double mass vibrating system may easily be represented by equivalent electrical circuits which are in turn useful for analysis. Multimass vibrating systems like transformers do not have straightforward methods which can enable analysis of noiselevels. This paper attempts to develop such a method by extending the method applicable to a double mass vibrating system. Then the validity of the method is tested using a transforme

Factors Affecting Capacity Utilization In Industries: Hierarchical Analysis, M Victor

Tanzania Journal of Engineering and Technology (TJET)

This paper provides a hierarchical analysis of the factors affecting capacity utilization in Tanzanian industries. Several factors were identified and sent to randomly selected industries in Tanzania for ranking. The collected data was summarized and analyzed. The analysis made use of a known procedure, the 'Analytical Hierarchy Process' (AHP). The final results shows a ranking of the factors, on various hierarchical levels as to their percentage contribution in lowering the capacity utilization.

Effects Of Feed Solids Concentration On Dual Functionality Of A Hydrocyclone., Zanzu M

Tanzania Journal of Engineering and Technology (TJET)

The dual functionality, i.e. thickening and classification of a 50.8mm diameter hydrocyclone has been investigated. A metallurgical slime consisting of a 50% mixture of quartz and petroleum coke was used in the tests. It was found that in order to achieve both thickening and classification at the same time, the pressure drop across the hydrocyclone, the underflow diameter and the feed solids content have to be subtly controlled.

Simulation And Modeling Of Kinetics Of Silicon Oxidation In The Thin Oxide Regime, Tirthankar Dutta

Theses

Thermal oxidation of Silicon in dry O₂, in the thin regime(< 500A) is of vital importance to VLSI device engineers, because thin layers of SiO₂ are exclusively used as gate dielectric for high performance of MOS devices. There exist a number of models to explain the kinetics of oxidation in this thin regime. However there is considerable variance among them and the reported rate constants, which are supposed to describe the oxidation process. Rather than arriving at an alternative model, the present study aims at an extensive study and simulation of existing models of oxidation in dry oxygen, in the thin regime, with a recent set of experimental data and …

Advanced Manufacturing Applications Of Cost Estimating Techniques For Metal Cutting Industries, Zubair Hamid

Theses

In this work, different cost estimating techniques in metal cutting industry were studied. A basic understanding of estimation concepts were given. The typical breakdown of total cost was also given and discussed in details. Practical applications of cost estimating is studied. The effect of different parameters which relate to the lot sizes or quantity were discussed. All these results show that total cost is minimum at a point which is called least cost point, after that cost increases because of the addition of extra resources, in terms of man, machine and increase in administrative expenses.

Biodegradation Of Tnt (2,4,6-Trinitrotoluene), Jin Lou

Theses

This study summaries the results of various methods treating 2,4,6-trinitrotoluene (TNT). Review of available literatures revealed that the most commonly used techniques in full-scale plant for TNT removal are chemical oxidation and carbon adsorption.

From economic point of view, the biological treatment system will be much more cost-effective. Various methods for improving the efficiency of biological system treating TNT wastewater were developed in the laboratory. Current laboratory results show that by isolating appropriate microorganisms under adequate conditions, TNT wastes can be degraded successfully.

At the some time, some pretreatment technologies are recommended in this study for improving the performance of …