406 research outputs found
Bridge monitoring and management system using GIS
In this modern world, the use of computer technology in most of the parts of life are necessary especially in engineering scopes. With an advanced technology system, engineers are able to solve the problems encountered from the unexpected situations with an effective ways. Bridge monitoring and management system encompasses the important aspects to be taken in its lifecycle and life span of the bridge. Effective and practicability of system developed allow bridge practitioners to collect, process, analyses, visualize and presented the database information through a moderate medium of delivery among the users. GIS acts as a tools for a bridge practitioners to provide spatial solutions for a problems encountered in spatial data handling for a bridge. This paper discussed about the GIS approach in the monitoring and management system for a bridge structure
Síntesis de ésteres de acetato hexilo, mediante transesterificación química a partir de palma como base sintética de fluidos para sondeos
In the present study the synthesis of a palm based ethylhexyl ester was examined through a transesterification reaction of palm oil methyl ester (POME) with 2-ethylhexanol (EH). A sodium methoxide in methanol solution was used as a catalyst. The reaction was carried out at a fixed pressure of 1.5 mbar by varying the temperature (80–140 °C), POME/2EH molar ratio (1:1.5–1:2.2), reaction time (0.5–4 h) and catalyst concentration (1–2% w/w). The reaction with 2-ethylhexanol involved a single step reversible reaction, thus, the reaction was completed in a very short time. The optimum conditions were obtained in less than 30 minutes with 1.5 mbar pressure, 70 °C, and 1:2 molar ratio of POME to 2EH. The analysis of the final product (ethylhexyl ester) was performed using gas chromatography which exhibited 98% of ethyl hexyl ester yield. The gas chromatography analysis of ethyl hexyl ester revealed two major esters peaks i.e. ethyl hexyl palmitate and ethylhexyl oleate.En el presente estudio se analizó la síntesis de ésteres de acetato de hexilo de palma mediante reacción de transesterificación de los ésteres metílicos de aceite de palma (PME) con 2-etilhexanol (EH). Como catalizador se utiliza una solución de metóxido de sodio en metanol. La reacción se lleva a cabo a presión fija de 1,5 mbar mediante la variación de temperatura (80–140 °C), relación molar POME/2EH (1:1.5–1:2.2), tiempo de reacción (0,5–4 h) y concentración de catalizador (1–2% w / w). La reacción con 2-etilhexanol implica un solo paso de una reacción reversible, por lo tanto, ésta se completa en un tiempo muy corto. Las condiciones óptimas se obtuvieron en menos de 30 min a 1,5 mbar, 70 °C y una relación molar de 1:2 de POME al 2EH. El análisis del producto final se realizó usando cromatografía de gases que mostró un rendimiento del 98% del etilhexil éster. El análisis de la cromatografía de gases del etilhexil éster muestra dos grandes picos correspondientes a los ésteres palmitato y oleato de etilhexilo
Rock bearing resistance of bored piles socketed into rock
In view of the large movement required to mobilise the base resistance of bored piles and difficulty in base cleaning, the end bearing resistance often ignored in current design practice that will result in excessive rock socket length. Many attempts have been made to correlate the end bearing resistance with the uniaxial compressive strength of intact rock and the RQD but it is uncertain how applicable they are to rock type in Malaysia. This paper attempts to review the applicability of the formulas from previous studies to rock type in Malaysia. A program of field tests for 13 bored piles with diameter varying from 1000 mm to 1500 mm constructed in granite was conducted to measure the axial response of bored piles, tested using static load test and high strain load dynamic test to verify its integrity and performance. The results were evaluated and compared to the predicted rock bearing resistance. Based on the result obtained, the method by AASHTO gives the best prediction of rock bearing resistance for granite in Malaysia. However the relationship between compressive strength and rock discontinuities with the rock bearing resistance showed scattered results
Metal concentration at surface water using multivariate analysis and human health risk assessment
This study defined the concentration of metals in Kerteh and Paka River water and their potential health risk towards human. 54 water samples were collected and analyzed using ICP-OES. Results revealed that most of the stations in Kerteh River gave the higher concentration of Cd, Cu, Zn, Co, Ni, As, Cr and Pb compared to Paka River. However As, Cr and Pb have exceeded the permissible limit of Malaysia standard for all stations in both rivers. Cd, Cu, Zn, Co and Ni were below than Malaysian standard permissible levels during the sampling period. The principal component analysis (PCA) revealed that both geogenic and anthropogenic sources were responsible to possible metals contamination in both rivers. Moreover, risk assessments for all metals were within the safe limits, except for As in the Kerteh River for both adult and child as well as to Paka River for both genders
Finite Element Modelling and Updating of Motorcycle Structure with Suitable Length of Connecting Element
This paper attempts to present an appropriate way to model welded joints in a motorcycle structure using the finite element method. Joint modelling strategy was implemented in this study since the joint itself has a significant influence as local effect on dynamic behavior of a structure. The objective of the paper is to investigate the suitable length of connecting element for joints of the structure. The length of the gaps of the parts is a 3mm, 10mm and 15mm was created in 3D model of structure for this joint modelling purpose. The element connectors that available in the FEA software were utilized to model the welded at assembled parts on test structure in this study. Two locations were used on the FE model for modelling of welded joints such as CBAR element connector used to replicate spot weld joint. Ahead of the updating process, sensitivity analysis is made to select the most sensitive parameter for updating purpose. Optimization algorithm in MSC Nastran is used in FE model updating process. The results show that employing a gap connecting element as an updating parameter (3mm) offers greater convergence than using significant parameters. This paper concluded that suitable length of connecting element for joint structure with CBAR element connector is attainable to replicate the real welded motorcycle structure since it has the lowest discrepancy in correlation analysis
Sequestration of carbon dioxide using ground granulated blast furnaces slag and kaolin mixtures
Mineral carbonation has been utilised extensively worldwide as the most important way of permanently sequestering carbon dioxide (CO2). This study objective includes sequestering of CO2 gas from atmosphere via carbonation of magnesium and calcium. Waste materials such as ground granulated blast furnaces slag (GGBS) extracted through iron manufacturing as well as brown kaolin mixtures were employed. Acid digestion method as well as thermogravimetric analysis were employed to quantify CO2 sequestered by GGBS-kaolin mixtures. The outcomes indicated that the acid digestion technique is more dependable compared to TGA in measuring CO2. Nonetheless, both methods deduced that the quantity of CO2 sequestered is about 5% from the total dry mass of the mixtures. Thus, GGBS-kaolin mixtures effectively sequester a substantial quantity of CO2
Application of zero-truncated count data regression models to air-pollution disease
Count data consist of non-negative integers that have many applications in various fields of studies. To handle count data, there are various statistical models that can be employed corresponding to the properties of the count data studied. Poisson regression model (PRM) is mostly used to model data with equidispersion, while negative binomial regression model (NBRM) is a model that is regularly employed to model over-dispersed count data. On the other hand, the usual count data regression models may not able to handle strictly positive counts. In this case, the appropriate model for the analysis of such data would be models truncated at zero. We are interested to study the relationship between pollution related disease with influential factors such as air pollution and climate variables in Johor Bahru, Malaysia, using these zero-truncated models, where the number of disease cases are strictly positive. In particular, the zero-truncated PRM and NBRM are used to determine the association between the number of dengue patients and their influential factors. From the study, zero-truncated NBRM is found to be the best model amongst the two models to model the relationship between the number dengue cases and air pollution and climate. Air pollution factors that significantly affect the number of cases for dengue are particulate matter (PM10) and sulfur dioxide. Also, humidity and temperature are the climate factors that significantly affect the number of dengue cases
Geochemistry characterisation of marine clay
In evaluating a suitable type of stabiliser, investigating geochemical characteristics is important for improving the properties of soil. This paper assessed the geochemistry of marine clay samples collected from Batu Pahat, Johor, Malaysia. The parameters investigated were pH, loss on ignition (LOI) and the quantities of sulphate, chloride, nitrate and carbonate ions. The results revealed that the clay was an acidic soil with pH of 3.25 and containing 8% of organic matter. The clay also contained 6,071 mg/l, 281 mg/l and 22 mg/l of sulphate, chloride and nitrate ions, respectively. Sulphate and chloride ions from acid rain and decomposed organic matters are the leading causes of acidity found in clay. Further investigation of the physical properties of the soil further indicated that it belonged to a group of clay having high plasticity (CH) and is unsuitable for construction purposes in its natural condition. The concentration of sulphate ions in the clay sample also advocated that the soil is not suitable to be stabilised using cement or lime due to the risk of the formation of a complex compound of calcium sulphoaluminate hydrate (ettringite). Additionally, the sulphate in the marine clay is likely to attack the concrete of the foundation of future infrastructures that may be built in the study area
A sustainability performance assessment framework for palm oil mills
The palm oil industry has had to undergo rapid development in order to cope with the increasing demand from consumers year by year. The palm oil industry is receiving criticism from various parties on the issue of sustainability. This paper presents the development of a Palm Oil Mill Sustainability Index that enables millers to assess the sustainability performance of palm oil mills against benchmarks, and to differentiate between the performance of each mill. The assessment was performed via the adoption of a Proximity-to-Target approach that measures the current sustainability performance of the industry relative to policy targets. The industry's comparable performance was observed in terms of sustainability and indicators through a graphical method. The resulting Palm Oil Mill Sustainability Index scores were translated into a five-point rating system to describe the sustainability performance levels for different mills i.e. excellent, good, fair, poor, and very poor. Based on the Palm Oil Mill Sustainability Index scores and rating system, weak performance indicators were identified, for example, excessive use of water consumption due to inappropriate operation of hydrocyclones. By identifying the weak performance indicators, practical recommendations and measures for improvement can be proposed and the Palm Oil Mill Sustainability Index scores recalculated to evaluate the effectiveness of the proposed sustainability performance strategy. Selected palm oil mills in Malaysia were used as a case study to demonstrate the applicability of the framework. The results provide empirical evidence to support a decision-support-system for enhancing palm oil mill sustainability performance, so as to achieve a balance between environmental, economic, and social aspects in the palm oil mill sector
Unmanned Aerial Vehicle (UAV) for Slope Mapping at Perumahan Gambang Damai, Pahang: A Case Study
This paper discusses the applications of unmanned aerial vehicle (UAV) for slope mapping and its important parameters including perimeter, area and volume of certain selected areas at Perumahan Taman Gambang Damai in Kuantan Pahang. Previous work of slope mapping using traditional survey equipment considered as time consuming and very challenging especially in hilly regions. This study also focused on determining the potential slope hazard based on slope angle. Modern UAV able to take high quality image which essential for the effectiveness and nature of normal mapping output such as Digital Elevation Model (DEM) and Digital Orthophoto. These photos captured by the UAV will later exported to Agisoft to generate full map of study area. With the help of Global Mapper, the measurement such as perimeter, area and volume of selected study areas can be determined easily and considered as the main interest in this study. Based on the results of the two slopes (slope A and slope B), slope B give a bigger volume which is 1469.7 m3 compare to slope A which is 1382.9 m3. The enclosed area for slope A is 1634.3 m2 which is bigger compare to slope B which is 766.86 m2. Besides, the perimeter of slope A is 162.28 m which is bigger compare to slope B which is 159.45 m. In addition, another outcome of this study is, this modern method of mapping helps researchers and engineers to study the possibility of slope hazard based on their respective slope angle. From the results, the angle for slope A is 47.35. while the angle for slope B is 54.75. . Both of the slopes considered as very steep slope. In conclusion, modern technology of UAV proves to be very effective for mapping in geotechnical engineering. Slope mapping using multi-rotor UAV help researchers and engineers to obtain slope measurement within short period of time compare to previous traditional method
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