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Information And Communication Technology Applications In The Tanzanian Health Sector, M Victor Dec 2004

Information And Communication Technology Applications In The Tanzanian Health Sector, M Victor

Tanzania Journal of Engineering and Technology (TJET)

The potential role of Information and Communication Technology (ICT) in the health sector is to improve the delivery of health services and would also help to deal with major constraints in uplifting the health standards Of Tanzanians. ICT in heath can be used to facilitate remote consultation, diagnosis and treatment. The objective Of the study was exploratory in nature and aimed at determining the awareness level of the länzanian health sector on various ICT applications which could be used in the sector. The study also aimed ar establishing the challenges to the implementation of ICT in the Tanzanian health sector. …

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Assessment Of The Accuracy Of Approximate Methods In The Analysis Of Plane Frame Structures, I Rubaratuka Dec 2004

Assessment Of The Accuracy Of Approximate Methods In The Analysis Of Plane Frame Structures, I Rubaratuka

Tanzania Journal of Engineering and Technology (TJET)

pproximaic methods of analysis are widely used in the analysis OJ' frames for preliminary design due to their simplicily as compared to exact analysis meth o ds Ough they a re nol as accurate. In this paper. the methods Of hinges and portal frame are described and have been used to analyze a statically indeterminate frame by taking inro account the bending stiffness of the frame members. The obtained results are comparable Io the magnitudes of forces determined by exact methods Of analysis.

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Review Of The Product Development Process And Information Flow In The Manufacturing Industry: Problems And A Possible Wav Forward, E Opiyo Jun 2004

Review Of The Product Development Process And Information Flow In The Manufacturing Industry: Problems And A Possible Wav Forward, E Opiyo

Tanzania Journal of Engineering and Technology (TJET)

No abstract provided.

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Field Evaluation Of Soil Physical, Chemical And Hydraulic Property Changes Caused By Surface Water Application: A Case Study Of Ruaha-Mbuyuni Irrigation Scheme, Iringa, Tanzania, A Tarimo Jun 2004

Field Evaluation Of Soil Physical, Chemical And Hydraulic Property Changes Caused By Surface Water Application: A Case Study Of Ruaha-Mbuyuni Irrigation Scheme, Iringa, Tanzania, A Tarimo

Tanzania Journal of Engineering and Technology (TJET)

The conventional metering. pyepa.vmen,' and estimates have been used in power utilities industries. The svslen,'s hare experienced many problems such as power tampering, bill tampering, ./åiluve ro receive invoices by poner unlity customers and so on. Different technologies have been investigated To overcome the problems and recently it has been realized that remote 'nonitoring sysle•ns through powerline channel is a solution offhese problems in Tanami". However. 'he powerline network has been used for electrical power IO use i,' for implementation of remote monitoring: network must be setup and has to be modeled to accommodate communications. The contribution has analyzed 'he …

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Introduction Of Seismic Resistance Features In The Construction Of Buildings In Tanzania, I Rubaratuka Jun 2004

Introduction Of Seismic Resistance Features In The Construction Of Buildings In Tanzania, I Rubaratuka

Tanzania Journal of Engineering and Technology (TJET)

Available dara indicates that a greater part of Tanzania lies within a seismic region. to date most Of the buildings in the country have been designed and constructed without considering seismic loads. In addition no design codes have been developed to guide the seismic design for buildings and other related structures in Tanzania. This paper outlines the basic design concepts, which are useful during the design of seismic resistant buildings before the seismic design code is developed and adopted in Tanzania.

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Derivation And Analysis Of Maximum And Conditional Work Of An Electromagnet In Relays With Small Gaps And Constant Armature Load, Dominic Chambega Jun 2004

Derivation And Analysis Of Maximum And Conditional Work Of An Electromagnet In Relays With Small Gaps And Constant Armature Load, Dominic Chambega

Tanzania Journal of Engineering and Technology (TJET)

No abstract provided.

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Mathematical Simulation Of The Influence Of Volatile Ma•Rrer Cloud On Heterogeneous Ignition Of Single Coal Particles, Hassan Ratal Ambula Jun 2004

Mathematical Simulation Of The Influence Of Volatile Ma•Rrer Cloud On Heterogeneous Ignition Of Single Coal Particles, Hassan Ratal Ambula

Tanzania Journal of Engineering and Technology (TJET)

Asimple model has been developed to predict the heterogeneous ignition temperature for single coal particles under conditions of negligible, natural and forced convections. These conditions cause different sizes Of volatile matter cloud that surround the coal particle. The model is based on the ignition Of a single coal particle heated by irradiation from spot heaters in a cold (ambient) surrounding. Energy from the particle surface oxidation, volatile matter combustion and physical heating from the spot heaters are all included in rhe particle energv balance. General ignüion criterion is used to determine the ignition point. The agreement between the experimental and …

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Probabilistic Load Flow For Mv Radial Distribution Networks Supplying Statistical Loads, B Kundy Jun 2004

Probabilistic Load Flow For Mv Radial Distribution Networks Supplying Statistical Loads, B Kundy

Tanzania Journal of Engineering and Technology (TJET)

Aecurate load models are required Jör 'he computation OJ' load on Medium Voltage (MV) distribution net•.vovk.s_ Modern microprocessors in recent times have enabled researchers stunple and log domestic loads. The findings show that domestic loads are stochastic in nonwe and are best described bv u beta probability distribution [Herman et al. 1999]. The statistical evaluafion lhe consumer voltages requires description load currents al rhe lime e/ lhe system maximum demand. In this paper. an analytical 1001 computing voltage vegulation on MV distribution net-norks fi•eding statistical louds is presenled. To deal beta- distributed currents on MV distribution networks, new scaling factors …

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Service And Network Modeling For Implementation Of Powerline Remote Monitoring Of Electrical Power Metering In Tanzania, J Anatory Jun 2004

Service And Network Modeling For Implementation Of Powerline Remote Monitoring Of Electrical Power Metering In Tanzania, J Anatory

Tanzania Journal of Engineering and Technology (TJET)

The conventional metering. pyepa.vmen,' and estimates have been used in power utilities industries. The svslen,'s hare experienced many problems such as power tampering, bill tampering, ./åiluve ro receive invoices by poner unlity customers and so on. Different technologies have been investigated To overcome the problems and recently it has been realized that remote 'nonitoring sysle•ns through powerline channel is a solution offhese problems in Tanami". However. 'he powerline network has been used for electrical power IO use i,' for implementation of remote monitoring: network must be setup and has to be modeled to accommodate communications. The contribution has analyzed 'he …

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Importance Of Structural Fire Protection In Reinforced Concrete Buildings: A Case Study Of Ex-Nasaco Building In Dar Es Salaam, I Rubaratuka Jun 2004

Importance Of Structural Fire Protection In Reinforced Concrete Buildings: A Case Study Of Ex-Nasaco Building In Dar Es Salaam, I Rubaratuka

Tanzania Journal of Engineering and Technology (TJET)

Reinforced concrete is concrete that is internally reinforced with steel bars or mesh. This gives rhe malerial the compressive strength of concrete along wilh the tensile strength Of steel. Reinforced concrete does not perform well under fire conditions as it spalls and loses strength. Heating Causes a failure Of the bond between concrele and sleels bars and this results in reduction of strength of concrele. Strength of concrete decreases With increase in temperature and increase With time. In order to provide fire resistance to structural components/elements in buildings, it is important Io consider the type of aggregates to be used. …

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Evaluation Of Long-Shore Sediment Transport On The Kunduchi Beach Tidal Flat, Dar Es Salaam, Alfonse Dubi Jun 2004

Evaluation Of Long-Shore Sediment Transport On The Kunduchi Beach Tidal Flat, Dar Es Salaam, Alfonse Dubi

Tanzania Journal of Engineering and Technology (TJET)

Kunduchi Beach is located approximately IO kilometres north Of Dar es Salaam City on the coasl of Mainland Tanzania. Currents and sediment concentrations were measured using a multi-sensor self-recording current meter. Waves Were measured using pressure gauges. Some physical features were visually measured. The general orientation of the shoreline is 330 degrees and the tidal flat is characterised by ripples. A1 aboul 150 m from the shoreline, ripples are 7-9 cm high and their wavelength is about 40 cm. Closer to the beach, ripple orientation is 350 degrees: ripple height is 5 cm and ripple wave length is 5 cm. …

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An Integrated Model For Technology Assessment And Choice For Rural Development In Developing Countries, Abdallah Chungu Dec 2003

An Integrated Model For Technology Assessment And Choice For Rural Development In Developing Countries, Abdallah Chungu

Tanzania Journal of Engineering and Technology (TJET)

Abstract

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Evaluation Of Pollution Loading Into Msimbazi River By Rapid Assessment And Direct Measurement Methods, J. H. Y. Katima Dec 2003

Evaluation Of Pollution Loading Into Msimbazi River By Rapid Assessment And Direct Measurement Methods, J. H. Y. Katima

Tanzania Journal of Engineering and Technology (TJET)

This paper assesses the suitability of Rapid Assessment (RA) methodology as a tool for making an environmental pollution inventory in data poor situation. The RA method was applied to estimate Biological Oxygen Demand (BOD), nitrogen and phosphorous loading into the Msimbazi River in Dar es salaam, Tanzania. The Direct Measurement (DM) was done to validate the results obtained from RA. The methodology is based on estimating waste loads from function variables such as production rate, population, etc. and pollution intensities from domestic, industry and agricultural sources. The incorporation of penetration factors for waste loads reduction refines the assessment procedure. The …

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Prediction Of The Response Of Rectangular Cladding Panels To Wind Loading In The Time Domain, Ambrose Shirima Dec 2003

Prediction Of The Response Of Rectangular Cladding Panels To Wind Loading In The Time Domain, Ambrose Shirima

Tanzania Journal of Engineering and Technology (TJET)

The analysis and subsequent design of cladding panels is traditionally based on quasi-static calculation of the wind loads. Pressure coefficients, which are derived from wind tunnel measurements and a design wind speed, are used to compute the wind loading. The codes of practice give the pressure coefficients and the guidelines of deriving the design wind speed from factors, which are specific to the site namely basic wind speed, topography, ground roughness and height above the ground. The concept of design wind speed is simple but it overlooks the resonant vibrations caused by the wind. The paper discusses a procedure for …

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Surface Titration Of Colloidal Alpha-Alumina, J. W. Ntalikwa Dec 2003

Surface Titration Of Colloidal Alpha-Alumina, J. W. Ntalikwa

Tanzania Journal of Engineering and Technology (TJET)

The surface charge density (σ₀) of colloidal alumina (α-Al₂O₃) suspended in 1:1 electrolytes (NaCl, NaNO₃, CsCl and CsNO₃) at different electrolyte concentration (c₀) was determined using acid-base titration. The data were described in terms of the Triple Layer Model (TLM) of electric double layer. It was observed that the polarity of σ₀ could be varied through a point of zero charge (PZC) by varying the pH of the suspension. The PZCs were observed to occur at pH = 7.8 ± 0.1, 7.6 ± 0.2, 8.5 ± 0.1 and 8.3 ± 0.1 in NaCl, NaNO₃, CsCl and CsNO₃, respectively. It was …

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A System Thinking Approaching Maintenance, Production And Quality, E. A. M. Mjema Dec 2003

A System Thinking Approaching Maintenance, Production And Quality, E. A. M. Mjema

Tanzania Journal of Engineering and Technology (TJET)

The concepts of system thinking and its applicability in maintenance management was analysed in this article. The author analysed various maintenance policies, which have inclination to the concept of system thinking. The maintenance policies revisited include the Integration of Maintenance (IM), Total Quality Maintenance (TQMain), Failure Mode and Effect Analysis (FMEA), and Total Productive Maintenance (TPM). All these strategies are aimed at utilising effectively the maintenance personnel by giving some of the responsibilities of maintenance to production personnel. It was found that, although the founder of these techniques did not mention the concepts of system thinking in their methods, however, …

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Centrifugal Extraction Of Avocado Oil From The Pulp, J. W. Ntalikwa Dec 2003

Centrifugal Extraction Of Avocado Oil From The Pulp, J. W. Ntalikwa

Tanzania Journal of Engineering and Technology (TJET)

Absract

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Load Flow Solution For Three-Phase Mv Radial Distribution Connected Network Supplying Different Line Topologies, B. J. Kundy Dec 2003

Load Flow Solution For Three-Phase Mv Radial Distribution Connected Network Supplying Different Line Topologies, B. J. Kundy

Tanzania Journal of Engineering and Technology (TJET)

In this paper, a load flow solution for the Medium Voltage (MV) three-phase radial distribution in delta-delta (Δ–Δ) connected network supplying different line topologies such as three phase, phase to phase and single-wire earth return (SWER) networks is presented. The general voltage related network equations are developed using Kirchhoff’s voltage and current laws. Development of a solution to the load flow analysis applying the developed general voltage related network equations is proposed in order to evaluate the network voltage profile. Various numbers of arrays are developed for the identification of the network under study. The proposed method is a new …

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The Inclusion Behaviothe Inclusion Behavior Of Sodium Compounds In Sub-Micron Particles Formed During Coal Combustionr Of Sodium Compounds In Sub-Micron Particles Formed During Coal Combustion, Iddi Mkilaha Dec 2003

The Inclusion Behaviothe Inclusion Behavior Of Sodium Compounds In Sub-Micron Particles Formed During Coal Combustionr Of Sodium Compounds In Sub-Micron Particles Formed During Coal Combustion, Iddi Mkilaha

Tanzania Journal of Engineering and Technology (TJET)

During combustion of coal, biomass and sewage sludge, metallic compounds especially alkali metals such as sodium and potassium vaporize and form fumes which are emitted with the exhaust gases. These fumes are corrosive to the turbine blades of power plants. To minimize corrosion, efforts have been made to control the condensation phase of these metals. In this study, the evolution and inclusion of sodium in sub-micron particles was investigated using a drop tube furnace and a low-pressure impactor (LPI). Four types of coal with different chemical properties were tested. The results suggest that a reaction-controlled mechanism and nucleation via chemical …

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Simulation Of The Communication Process In A Pin Mill, Ambrose J. M. Itika Dec 2003

Simulation Of The Communication Process In A Pin Mill, Ambrose J. M. Itika

Tanzania Journal of Engineering and Technology (TJET)

Prediction of the performance of comminution equipment by mathematical models and simulation poses a great challenge to the chemical engineer. This paper describes the simulation of grinding results obtained using an impact mill. Single particle results have been used to generate breakage and selection coefficients that were used for the evaluation of the model. Results have shown that simulation model is in good agreement with the experimental data obtained at a circumferential speed above 60 m/s. At lower speeds, the models shows only partial agreement in the middle particle size ranges. The application of the model is therefore limited for …

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Using Pedotransfer Functions To Predict Saturated Hydraulic Conductivity For Layered Soil Profiles A Case Study At The Sokoine University Of Agriculture Farm, Tanzania, M. K. Mulengera Dec 2003

Using Pedotransfer Functions To Predict Saturated Hydraulic Conductivity For Layered Soil Profiles A Case Study At The Sokoine University Of Agriculture Farm, Tanzania, M. K. Mulengera

Tanzania Journal of Engineering and Technology (TJET)

Saturated soil hydraulic conductivity (SHC), is useful for land resources management. But it is difficult, time consuming, and labour intensive to measure in the field. These problems can be overcome through the use of pedotransfer functions (PTFs), which relate the SHC to readily available soil physical, chemical, and biological parameters. The existing PTFs were developed in temperate countries using homogeneous core soil samples. Thus, these PTFs are not useful for tropical soils with different properties and for layered soil profiles. In this paper, field measured SHC values are related to representative profile soil properties (RSPSPs) that are determined using horizons’ …

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Salt Balance, Fresh Water Residence Time And Budget For Non-Conservative Materials For Makoba Bay During Wet Season, As Ngusaru, Aj Mmochi Dec 2003

Salt Balance, Fresh Water Residence Time And Budget For Non-Conservative Materials For Makoba Bay During Wet Season, As Ngusaru, Aj Mmochi

Tanzania Journal of Science

Water and salt budgets suggest that in order to balance the inflow and outflow of water at Makoba bay, there is net flux of water from the bay to the open ocean during wet season. Residual salt fluxes between the bay and the open ocean indicate advective salt export. Exchange of water between the bay with the open ocean plays a role of replacing exported salt via mixing. Calculated freshwater residence time for the bay is 63 days during wet season. Budget results for non-conservative materials indicate net DIP flux from the ocean to the bay and a net DIN …

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Application Of Robustness Analysis For Developing A Procedure For Better Urban Transportation Planning Decisions, Deogratias Eustace, Eugene R. Russell, E. Dean Landman Jan 2003

Application Of Robustness Analysis For Developing A Procedure For Better Urban Transportation Planning Decisions, Deogratias Eustace, Eugene R. Russell, E. Dean Landman

Civil and Environmental Engineering and Engineering Mechanics Faculty Publications

This paper shows that robustness analysis is a technique with a potential for aiding decision makers in choosing transportation investment projects. In this paper, it has been demonstrated that it can be successfully used in urban transportation planning in conjunction with urban travel demand software. The robustness analysis procedure emphasizes the need, under conditions of uncertainty, to make early decisions in a time-phased sequence, while preserving future options that currently seem attractive. The results of the robustness analysis from the case study used in this paper indicate that the method is simple to understand, easy to use, minimizes future surprises …

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Treatment Of Chlorinated Volatile Organic Compounds Using Wetland Systems, Gabriel Roderick Kassenga Jan 2003

Treatment Of Chlorinated Volatile Organic Compounds Using Wetland Systems, Gabriel Roderick Kassenga

LSU Doctoral Dissertations

Bench-scale continuous vertical flow column and microcosm studies were conducted to investigate the attenuation potential of chlorinated volatile organic compounds (CVOCs) in constructed wetland soil mixtures prepared from peat, compost and sand and in a pristine natural freshwater wetland soil. The study also determined geotechnical properties of potential synthetic peat mixtures for construction of treatment wetlands for CVOCs. Trichloroethene (TCE), cis-1,2-dichloroethene (cis-1,2-DCE) and 1,2-dichloroethane (1,2-DCA) were the main test chemicals used during the studies. Based on geotechnical and sorption characteristics, two mixtures (one comprised of sand and peat and the other comprised of sand, peat and compost product) were selected …

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Derivation Of An Expression That Defines The Pulling Forces In Relays With Small Operating Gaps, D. J. Chambega Dec 2002

Derivation Of An Expression That Defines The Pulling Forces In Relays With Small Operating Gaps, D. J. Chambega

Tanzania Journal of Engineering and Technology (TJET)

This paper derives an expression that defines magnitude of the pulling force developed in relays with small operating gaps, that is, when the length of the operating gap in between the yoke and the armature is small as compared to the area of the poles at the yoke. To obtain the expression, saturation of the core material is not considered. Results from the expression are then compared with those obtained experimentally. The comparison is found to deliver acceptable accuracy.

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Discrete Element Modelling Of The Abrasive Dehulling Process Of Sorghum And Millet, E. L. Lazaro Dec 2002

Discrete Element Modelling Of The Abrasive Dehulling Process Of Sorghum And Millet, E. L. Lazaro

Tanzania Journal of Engineering and Technology (TJET)

The abrasive dehulling process of sorghum and millet was modelled using a three-dimensional discrete element model. The model was validated by comparison between experimental and simulation results. Good correlation between experimental and simulation results was obtained. Several numerical experiments were also carried out using the developed model to investigate the influence of mill and grain parameters on dehulling of sorghum and millet. The simulated results correlated well with experimental results from literature. The developed model therefore provides a simple and cheap tool, which can be used to study the dehulling process in more detail than, is currently possible using the …

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Effect Of Moisture And Loading Orientation On The Mechanical Properties Of Sorghum And Millet, E. L. Lazaro Dec 2002

Effect Of Moisture And Loading Orientation On The Mechanical Properties Of Sorghum And Millet, E. L. Lazaro

Tanzania Journal of Engineering and Technology (TJET)

Uniaxial compression properties of sorghum and millet grain at different moisture contents (12–25% dry basis) and at different kernel orientation were investigated. These included: modulus of deformability, maximum compressive force, deformation and toughness at grain break point. Individual grain kernels of two varieties of sorghum, (Dionje and Jumbo) and one variety of pearl millet, (IM) at 12, 15, 20, and 25% moisture content dry basis (mc.db), were quasi-statically loaded using a J.J.universal tensile testing machine to their breaking point. The modulus of deformability, maximum compressive force required to initiate grain rupture and the grain toughness (energy absorbed at break point …

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Potential For Use Of Sand In Road Construction In Dar Es Salaam And Coast Regions, Mfinanga A Dec 2002

Potential For Use Of Sand In Road Construction In Dar Es Salaam And Coast Regions, Mfinanga A

Tanzania Journal of Engineering and Technology (TJET)

Coarse aggregates for use in road construction in Dar es Salaam and Coast regions are becoming increasingly scarce and expensive while sand, which is cheaper, is readily available in the two regions. This research aimed at evaluating the possibility of using quarry sands in the two regions as a major constituent material in bituminous road pavement layers. First, the use of sand in sand-bitumen bases for low and medium trafficked roads was studied. The study then continued with the preliminary evaluation of the possible use of the sands in hot rolled asphalt mixes. Results show that Mbagala sand can be …

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Incorporating E-Commerce Technologies Into Small And Medium Manufacturing Industries In Tanzania, M. A.M. Victor Dec 2002

Incorporating E-Commerce Technologies Into Small And Medium Manufacturing Industries In Tanzania, M. A.M. Victor

Tanzania Journal of Engineering and Technology (TJET)

Businesses worldwide are making use of the new opportunities which have been brought up by the developments in Information and Communication Technologies (ICTs), particularly the Internet. Big businesses, especially those multinationals in the developed nations have invested heavily on these technologies and they are reaping their benefits. This paper reports on a study conducted to look at the key issues to be considered in order for small and medium enterprises (SMEs) in Tanzania be able to position themselves technologically in what is termed as E-commerce. Cost and benefits, policy, training and infrastructure issues are looked at in this study.

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Sustainable Data Acquisition Methods For Road Maintenance Management In Developing Countries, N. K.M. Mushule Dec 2002

Sustainable Data Acquisition Methods For Road Maintenance Management In Developing Countries, N. K.M. Mushule

Tanzania Journal of Engineering and Technology (TJET)

Whilst it may be argued that manual methods of pavement data collection are subjective, unsafe, involve high personnel costs and have low repeatability, the initial costs of acquiring automated systems coupled with the technology required to operate and maintain them can be prohibitive for most developing countries. Moreover, automatic measurement of surface distress has proved to be a difficult challenge to instrument designers. In many cases, manual methods are the only ones that can be employed. A research project was carried out to design a sustainable data collection scheme for network level management system for developing countries. A simple procedure …

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