Landfill site selection by integrating analytical hierarchy process and geographic information system

In solid waste management, landfilling is still widely practiced because it is convenient and consumer friendly. Unfortunately, many landfill sites have closed and cause problem in managing the waste. The purpose of this study is to suggest suitable and po tential sites for landfill in Johor Bahru area through mapping technique and database system . Analytical Hierarchy Process (AHP) is a method for analysis and supports decision where multiple and competing objectives are involved. Fifteen parameters were id entified to use in AHP process. In this method, the process is divided into hierarchy before pair wise comparison was done and the result is prioritizing according to their weightage. The process is continued with weightage evaluation and its consistency. Landfill site selection process involved many spatial data and strenuous in handling it. Geographic Information System (GIS) can give significant help because it can potentially handle large volume of data that need to be evaluated and processed. The metho d used in GIS is digitizing, buffering and overlays. As a result in AHP, the most important criterion is river weighted 0.149 of all criteria and the least important criteria are distance to main road weighted 0.028 of other criteria. In GIS method, there are six parameters selected which are main road, plantation, residential area, swamp, grassland and river coverage . The findings identified two potential sites for landfill area because it s atisfied all given requirements. I ntegration of GIS and AHP is su itable to be used in landfill site selection process because it will helps in locating new landfill site that is environmentally, economically and socially wise

A multivariate methodology for determining the optimal highway alignment candidate based on geographic

Research on highway alignment optimization has been quite intensive over the last two decades. Determining the best candidate for highway alignment is one of the most complex highway design stages due to the different effects of various parameters. Hence, in the present study, Analytic Hierarchy Process technique and Geographic Information System are proposed to determine the best highway candidate with special focus on the constraint, cost and safety criteria. The methodology presented in the current research is not limited to the constraint, cost and safety criteria but can be extended to other criteria. This methodology has been implemented on a case study region in northwestern of Iran, and therefore the constraint, cost and safety criteria have been obtained for the case study conditions. The final result of the current paper indicates that the optimal highway candidate obtained with the proposed methodology can concurrently satisfy all relative parameters in highway alignment optimization based on their impact

Analytical and statistical approaches to study the impacts of shoreline change towards mangroves at Kukup Island National Park, Johor

Shoreline and mangroves form a dynamic ecosystem to coastal area. They support and supply various foods and protections to ensure the sustainability of coastal ecosystem around the world. Despite these, information that exclusively emphasize on the interaction of shoreline change and mangroves on an island is still lacking, making assessment and observation towards coastal areas on island less significant. Hence, this study is significant to provide a first view of the interaction and the relationship and response of shorelines change towards mangrove physical characteristics. GIS, remote sensing as well as statistical analysis such as DSAS and linear regression were applied to support the study that consisted of three main stages which involve data collection, data processing and comparison of mangroves physical characteristics towards the changes in shoreline positions. Finding revealed that during the time span of 2005-2011, shoreline near to Sg Ular has experienced more erosion, resulted in the shoreline shifting that was ranged between -0.02 m/y and -1.52 m/y. Further analysis of shoreline change and mangroves physical characteristic unveiled that a significant relationship of mangrove characteristics and shoreline changes rates occurred at Sg Ular. It was found that mangroves communities along the shoreline of Sg Ular was negatively influenced by the shoreline change, possibly due to mild erosion along the shoreline towards the river mouth of Sg Ular

Implementation of project based learning for civil engineering students at Universiti Teknologi Malaysia

Implementation of Project Based Learning (PtBL) in Universiti Teknologi Malaysia (UTM) as part of Outcome Based Education (OBE) framework have faced various challenges (i.e revamp on the undergraduate co-curricullum, required high commitments from academicians & faculty and facilities to cater PtBL activities). This paper discusses the effectiveness of PtBL teaching method in an effort to develop the students’ soft skills in tandem with the technical or professional competencies; and problems, challenges and potential improvement in the course. The Survey Camp course which is offered at year one of a four years civil engineering degree programme in the Faculty of Civil Engineering (FKA), UTM was chosen for this study. It is a ten days fieldwork in which the students will carry out an engineering survey project from field to finish in groups of five to six students supervised by the academic staff. Assessment of the technical aspects was based on the students ability to meet the minimum engineering surveying’s standard whereas the assesment of soft skills was conducted during various sessions of the survey projects. Survey questionaires were given at the beginning and the end of the course as part of evaluation of the course effectiveness. The research has found that the technical aspects were achievable though with lesser degree for the engineering design. However, on the soft skills, students demonstrated an overall improvement of competency but it was difficult to determine the levels for the average students while the best and poor performers were easily observed

Wear prevention characteristics of a palm oil-based TMP (trimethylolpropane) ester as an engine lubricant

This paper presents the experimental results carried out to evaluate wear prevention characteristics of a palm oil-based TMP (trimethylolpropane) ester using a four-ball machine for different regime of lubrication. The TMP ester is produced from palm oil, which is biodegradable and has high lubricity properties such as a higher flash point temperature and VI (viscosity index). Three different regimes of lubrications are investigated, which hydrodynamic, elasto hydrodynamic and boundary lubrications. Under these test conditions, the wear and friction characteristics of different TMP samples are measured and compared. For boundary lubrication, it is found that up to 3% addition of Palm oil-based TMP ester in OL (ordinary lubricant) decreases the maximum amount of WSD (wear scar diameter) and reduces (COF coefficient of friction) up to 30%. Highest amount of load (220 kg) carrying capacity was also found from the contamination of 3% TMP. For hydrodynamic lubrication, addition of 7% of TMP reduces the friction up to 50%. It is well known that mechanical efficiency of machinery component increases with decreasing COF. The results of this investigation will be used to develop new and efficient lubricant to substitute the petroleum-based lubricant partially for automotive engine application

Assay for heavy metals using an inhibitive assay based on the acetylcholinesterase from Channa striatus

Acetylcholinesterase (AChE) is usually used as an inhibitive assay for insecticides. A lesser known property of AChE is its inhibition by heavy metals. In this work we evaluate an AChE from brains of striped snakehead (Channa striatus) wastes from aquaculture industry as an inhibitive assay for heavy metals. We discovered that the AChE was inhibited almost completely by Hg2+, Ag2+ and Cu2+ during an initial screening. When tested at various concentrations, the heavy metals exhibited exponential decay type inhibition curves. The calculated IC50 for the heavy metals Hg2+, Ag2+, Pb2+, Cu2+ and Cr6+ were 0.08432, 0.1008, 0.1255, 0.0871, and 0.1771, respectively. The IC50 for these heavy metals are comparable and some are lower than the IC50 values from the cholinesterases from previously studied fish. The assay can be carried out in less than 30 minutes at ambient temperature

Mapping the mangrove vulnerability index using geographical information system

A mangrove vulnerability assessment's goal is to generate recommendations for reducing vulnerability. Mangrove forests, which grow in the intertidal zones and estuary mouths between land and sea, exist in two worlds at once. Mangroves provide crucial stability for preventing shoreline erosion. It helps to maintain land level by sediment accretion while balancing sediment loss by serving as buffers catching materials washed downstream. Climate change, especially the associated increase in sea level, poses a serious threat to mangrove coastal areas, and it is critical to devise strategies to mitigate vulnerability through strategic management planning. Experts are attempting to determine how mangroves have been affected by climate change and rising sea levels. How do we forecast the consequences and effect of rising sea levels on mangroves, and then adjust and mitigate them accordingly? Vulnerability implies the risk of being assaulted or hurt, whether physically or emotionally. Environmental vulnerability is a feature of impact exposure as well as ecological systems' susceptibility and adaptive potential to environmental tensors. Researchers in this study ranked mangrove vulnerability on a scale of 1 to 5, with 1 indicating very low vulnerability and 5 indicating very high vulnerability. The Physical Mangrove Index (PMI), Biological Mangrove Index (BMI), and Threat Mangrove Index (HMI) are the three major groups of the Mangrove Vulnerability Index (MVI)). The study's main objective is to develop an accurate and efficient GIS database system that has been formulated and tested or implemented in three (3) separate areas, namely, Kukup Island, Tanjung Piai, and Sungai Pulai. The study develops a GIS-based Mangrove Vulnerability Index (MVI) Model for a selected ecosystem, and highlights mangrove vulnerability by ranking them from least to most vulnerable using parameters. The study also provides a forecast for the mangrove loss in the next 50 and 100 years, as well as to classify areas where mangroves are most vulnerable

Lubricity of bio-based lubricant derived from different chemically modified fatty acid methyl ester

In this research, polyol ester was used as the source of a biolubricant. The trimethylolpropane (TMP) and pentaerythritol ester (PE) were produced from palm oil methyl ester; they are biodegradable and have high lubricity properties. Two different conditions of lubrication were investigated. Under these test conditions, the wear and friction characteristics of different ester samples were measured and compared. The esters derived from PE and TMP had comparable characteristics to the fully formulated lubricant (FFL) in terms of the coefficient of friction (CoF). In terms of the mixed lubrication condition, the PE ester has the lowest CoF

Modal And FRF Based Updating Methods For The Investigation Of The Dynamic Behaviour Of A Plate / Mohd Syazwan Mohd Zin ...[et al.]

Accurate finite element models of engineering structures are of paramount importance to dynamicists to be used in predicting the dynamic behaviour of the structures. In order to have a finite element model that can accurately predict the structural behavior, measured data obtained from the test structure can be used to reconcile the finite element model and the procedures involved the reconciliation is model updating. The model updating methods, in general, are classified into two different classes which are the modal based updating and frequency response function (FRF) based updating. This research was aimed to investigate the efficiency, accuracy and economics between the FRF based and the Modal based updating on a thin aluminium plate structure. In this study, the measured results from the structure were obtained from the Experimental Modal Analysis (EMA) via LMS SCADAS. The structure was tested using an impact hammer and roving accelerometers. The test was performed under free-free boundary conditions. The initial finite element model of the aluminum plate was constructed and improved using both model updating methods. Then, the initial finite element results were compared with the experimental results for validation. The comparison of results revealed that the Modal based updating showed better capability to be used in reconciling the FE resonance frequencies to the measured counterparts with 6.02 percent of reduction in total error in comparison with the FRF based updating with 8.39 percent. Meanwhile, FRF based updating recorded much better capability to match the FE excitation and resonance frequencies with the measured ones

Tribological characteristics comparison of formulated palm trimethylolpropane ester and polyalphaolefin for cam/tappet interface of direct acting valve train system

Purpose There is a continuous drive in automotive sector to shift from conventional lubricants to environmental friendly ones without adversely affecting critical tribological performance parameters. Because of their favorable tribological properties, chemically modified vegetable oils such as palm trimethylolpropane ester (TMP) are one of the potential candidates for the said role. To prove the suitability of TMP for applications involving boundary-lubrication regime such as cam/tappet interface of direct acting valve train system, a logical step forward is to investigate their compatibility with conventional lubricant additives. Design/methodology/approach In this study, extreme pressure and tribological characteristics of TMP, formulated with glycerol mono-oleate (GMO), molybdenum dithiocarbamate (MoDTC) and zinc dialkyldithiophosphate (ZDDP), has been investigated using four-ball wear tester and valve train test rig. For comparison, additive-free and formulated versions of polyalphaolefin (PAO) were used as reference. Moreover, various surface characterization techniques were deployed to investigate mechanisms responsible for a particular tribological behavior. Findings In additive-free form, TMP demonstrated better extreme pressure characteristics compared to PAO and lubricant additives which are actually optimized for conventional base-oils such as PAO, are also proved to be compatible with TMP to some extent, especially ZDDP. During cylinder head tests, additive-free TMP proved to be more effective compared to PAO in reducing friction of cam/tappet interface, but opposite behavior was seen when formulated lubricants were used. Therefore, there is a need to synthesize specialized friction modifiers, anti-wear and extreme pressure additives for TMP before using it as engine lubricant base-oil. Originality/value In this study, additive-free and formulated versions of bio-lubricant are tested for cam/tappet interface of direct acting valve train system of commercial passenger car diesel engine for the very test time. Another important aspect of this research was comparison of important tribological performance parameters (friction torque, wear, rotational speed of tappet) of TMP-based lubricants with conventional lubricant base oil, that is, PAO and its formulated version