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This study presents a novel and comprehensive model development technique to predict the riverbank erosion rate for a natural channel using a Nonlinear AutoRegressive model with eXogenous inputs and QR factorization parameter estimation, known as the NARX-QR Factorization model. The model was developed based on a 12-month extensive field measurement at Sg. Bernam. This study established the governing factors and derived dependent and independent variables for riverbank erosion using dimensional analysis, based on the Buckingham PI theorem. Two functional relationships were derived from dimensional analysis incorporating the factors governing riverbank erosion. The functional relationships include parameters of hydraulic characteristics of the channel, riverbank geometry and soil characteristics. Parameter estimation was conducted using a linear least squares technique to quantify riverbank erosion rates. The significant independent variables and fourteen models with several numbers of hidden layers were set as the input parameters to the NARX-QR Factorization model. The model performance analysis shows that Models 1 and 9, developed based on the proposed NARX-QR Factorization model, have the highest R2 at 75% and 91%, respectively. Model 1 performed the best with accuracies for training and testing datasets of 75% and 73%, respectively. Additionally, the scatter plot of Model 1 is uniformly distributed along the line of perfect agreement. Therefore, it is concluded that the NARX-QR Factorization model developed in this study performed well in estimating the riverbank erosion rate, particularly for a natural river similar to Sg. Bernam.

Robustness analysis of model parameters for sediment transport equation development is carried out using 256 hydraulics and sediment data from twelve Malaysian rivers. The model parameters used in the analyses include parameters in equations by Ackers-White, Brownlie, Engelund-Hansen, Graf, Molinas-Wu, Karim-Kennedy, Yang, Ariffin and Sinnakaudan. Seven parameters in five parameter classes were initially tested. Robustness of the model parameters was measured on the statistical relations through Evolutionary Polynomial Regression (EPR) technique and further examined using the discrepancy ratio of the predicted versus the measured values. Results from analyses suggest (ratio of shear velocity to flow velocity) and (ratio of hydraulic radius to mean sediment diameter) to be the most significant and influential parameters for the development of sediment transport equation.

Green Technology design approach is a new solution that must be applicable to preserve a nature and reduce the pollution. There are so much innovation could be used to in the development of the park to reduce the electricity use, eco-friendly and livable for the community. This paper aims to exemplify an effort by a group of students, through multi-professional inputs, in designing for a city facility that can add more towards a livable city. The results of the approach are multidisciplinary design that includes the idea from multi-professional in making a livable park for community surroundings Tasik Biru Kundang, Kuang, Selangor, Malaysia. Keywords: Green technology; Livability; Multi professional; Design approach eISSN 2514-751X © 2018. The Authors. Published for AMER ABRA cE-Bs by e-International Publishing House, Ltd., UK. This is an open-access article under the CC BY-NC-ND license (http://creativecommons.org/licenses/by-nc-nd/4.0/). Peer–review under responsibility of AMER (Association of Malaysian Environment-Behaviour Researchers), ABRA (Association of Behavioural Researchers on Asians) and cE-Bs (Centre for Environment-Behaviour Studies), Faculty of Architecture, Planning & Surveying, Universiti Teknologi MARA, Malaysia.

Bank instability as a result of flow fluctuations may lead to massive bank erosions and subsequent damage of adjacent properties. Continuous erosion process promotes change in the river morphology, sedimentation problems due to the presence of secondary currents and local scouring at piers downstream of the erosion point. Knowledge on the extent of erosion should facilitate river engineers to resolve issues on river training works and river sedimentation problems. A study has been carried out in the field to quantify the amount of eroded materials using erosion pins that were driven into the ground normal to the bank surface. The erosion pins consist of 6 mm diameter metal rods and 60 cm – 80 cm in length. A spatial variation profile for rates of erosion has been identified with units expressed in unit cm per day. The defining parameters for bank erosion rates have included near-bank velocity, Ub, water depth, Y, stream bank geometry and soil bearing capacity. Development of empirical equations had used multiple linear and nonlinear regression techniques to determine the significant erosion predictors. It takes into consideration the coefficient of determination (r-squared) and Root-mean square error (RSME) as determinants for best predictors. Accuracy of developed equations is measured using the discrepancy ratio, D.R. This is the ratio of predicted to measured erosion rate. Analysis suggest that the equation derived using polynomial function (order-2) gave better accuracy compared to the equation derived using linear and power functions. An accuracy of 75% has been obtained. Scatter plots of the predicted to the measured erosion rates have shown to be between 0.5 – 2.0 within the line of good agreement.

Riverbank erosion is a complex soil-water interaction process, highly dynamic and constantly changing. Consequently, the estimation of riverbank erosion rate requires an in-depth understanding between the riverbank properties and the hydraulic characteristics of the river. Given the complexity of predicting riverbank erosion rate and the limitation of existing analytical solutions, this study developed empirical models that include the analyses of basal erosion and bank failure using 358 erosion pin measurement collected from River Bernam in Selangor, Malaysia. Field measurements of the river and sediment data were performed following strict international standard protocols and instrumentation, such as gauging and wading technique, survey pole and SEBA F-1 current meter. Based on 50 years of record, the mean annual flood in River Bernam is 10 m3/s. This study includes extensive analysis between each measured variable in representing the factors influencing riverbank erosion rates, development of empirical predictive models in quantifying riverbank erosion rates using statistical approach and improves predictive performance. Model parameterization was performed using sensitivity analysis and comparison of measured riverbank erosion rates with flow-induced variables yielded the strongest correlation, whereas other variables were found to be less significant. These variables were evaluated based on Pearson’s correlation coefficient, trend of the scatter plots and degree of determination. Novel findings from the sensitivity analysis of this study are one of the substantial factors in deriving the most influential parameters which constitutes to the rate of bank erosion. Multiple linear, non-linear and logarithmic functions were employed in the development of new predictive model. This study concluded that the developed empirical equations using logarithmic-transformation is the best predictor. Logarithmic-transformation equations show the highest percentage of accuracy and degree of determination, i.e. up to 93.5% and 0.783, respectively, and the data are between the limit of discrepancy ratio 0.5

Utilizing the river floodplain for the purpose of urban landscaping and eco-tourism benefit could greatly reduce the river width that would eventually increase flood intensity. This could possibly weaken the bridge foundation that increase the probability of bridge failures due to scour. The main objective of this study is to evaluate scour predictive formulae at a protruding abutment bridge in the compound channel, using Multiple Testing Problem (MTP) in a geometrical model of an Integral Abutment Bridge (IAB). The results of the MTP and graphical comparison yield satisfactory predictive formula. Findings of the current study can help determining maximum scour depth as an essential component of footing design to optimize both construction and maintenance costs.

Bars are important features in stream channel processes as they determine the flow and transport pattern. Many experimental works and field studies have been carried out which provides more information on this phenomenon. Several formulae are theoretically and empirically proposed for the bar height determination. Based on these considerations, a new relationship was developed which has considered two major groups of parameters namely, hydraulic characteristics and sediment characteristics. Establishment of the independent variables was carried out using dimensional analysis approach.

River meandering is a net outcome of erosion and deposition It initiates and develops width adjustment and planform evolution. Meandering process involves adjustment of the planimetric geometry and hydraulic factors. Many structures built within the vicinity of the river such as bridges, waterways/navigation and flood control contraptions are affected by river meandering and its distance. This research was carried out on a physical river channel model measuring 10m long, 2.4m wide and 1.8m deep located at Universiti Teknologi MARA Puncak Alam. Correlation analysis between the lateral migration rate, M and mean velocity, Umean to other variables. According to the physical consideration on lateral migration rate, M, there are three (3) major categories affecting channel bankline migration. There are hydraulic characteristics, water properties and soil properties, of which the latter is resistance to erosion. Therefore, the objective of this paper is to investigate the factors governing lateral migration rate for the development of an empirical model to predict lateral migration rate under the influence of non-migrating mid-bar.

Predicted total sediment load is usually used to identify the intensity of a sedimentation process. Currently, the existing available models to predict total load are mostly developed based on data collected from flumes, channels and rivers located in western countries. These models known as sediment transport model may not be valid to predict total sediment load of rivers in the tropics due to significant differences in the hydrological and sediment characteristics conditions. A new technique called Genetic programming (GP) technique is used to develop a new model to improve the prediction of total sediment load for rivers in tropical Malaysia. The new model named Evolutionary Polynomial Regression (EPR) model is compared with other three available sediment transport models using the different techniques including, Regression Equation, Modified Graf and Multiple Regression. Statistical analyses based on 82 data sets show the sediment transport model using this new technique perform well compare to other models.

Palm kernel shell (PKS) and empty fruit bunches, both raw (EFB-R) and pretreated by means of autoclaving (EFB-A) and microwave (EFB-M), were pyrolyzed in a fixed-bed stainless steel reactor at 550 °C. The yield of the water-soluble liquid fraction (pyroligneous acid, PA) in the pyrolysis of PKS was 26%wt. (dry basis) and in the range of 16–46%wt. when different EFB were used. The yield of insoluble liquid fraction (bio-oil, BO) was 9.1%wt. for PKS and up to 25%wt. in the case of EFB. Liquid and gaseous products were analyzed by conventional capillary gas chromatography. The PA from the PKS had 30%wt. of total phenolic compounds (up to 24%wt. phenol) and 46%wt. acetic acid. On the other hand, the bio-oil from PKS had 43%wt. of total phenolic compounds (up to 26%wt. phenol) and 17%wt. acetic acid. The PA from EFB contained mainly acetic acid (65.5%wt.), furfural (7.7%wt.), methanol (8.0%wt.), and phenol (15.2%wt.). When EFB was pretreated, the concentration of acetic acid in PA decreased dramatically, while the concentration of furfural increased up to ten times, this effect being more noticeable in the case of microwave pretreatment. The yields of by-products were of significance in all cases (13–23%wt. of gases and 33–52%wt. of char). These results show that the liquid products obtained from the pyrolysis of palm oil industrial wastes could be used in order to obtain chemical raw materials of worldwide extended use, while the by-products (gases and char) can be used as renewable energy sources.

The most challenging task during a flood event is to evacuate people from the affected areas to safer locations. The difficulty of this task is attributed to an uneven distribution of vehicles, a lack of timely assistance, a deficiency in decision making and poor coordination at the operational level. Although it is important to identify flood-prone areas, the assignment of vehicles to the appropriate evacuation routes is of primary importance. The latter consideration is a crucial determinant of the number of people who are saved in any emergency evacuation. This paper proposes an improved discrete particle swarm optimisation (DPSO) algorithm for solving the evacuation vehicle assignment problem (EVAP). Discrete particle positions are proposed that support the implementation of this DPSO. A min-max approach is used for the initial calculations of particle positions for the EVAP. This algorithm was computationally tested using different numbers of potentially flooded areas and compared with an average DPSO approach and with genetic algorithms. The findings of this study reveal that DPSO with a min-max approach that incorporates a new velocity clamping procedure offers good performance with respect to maximising the number of individuals who can be evacuated by vehicles from diverse locations for situations involving various numbers of potential flooded areas.

Soil erodibility has been identified as one of the major factors that govern threshold of resistance to erosion. Accurate measurement of soil erodibility in the field is indeed important for the determination of critical shear stresses. Critical shear stress is the stress that initiates particle movement that promotes shifting of the bankline. An attempt to establish soil erodibility parameters was successfully carried out using a newly fabricated Jet Erosion Device (JEd) based on soil properties. Soil erodibility coefficients are introduced to represent the erodibility of the soils under study. Statistical test is used to confirm the validity and accuracy of the proposed technique. Field data measurements were carried out on 3 rivers. Empirical models were developed using data from Selangor River and validated using data from Bernam and Lui rivers and other secondary river data. Analyses have shown high correlations and the parameters were further examined and analysed for the development of a predictive relationship for Ji. The most accurate model was selected based on the adjusted R2, standard error of the estimate and discrepancy ratio to illustrate its significance. Selection of the predictive variables was based on their ability to explain the variation of Ji. The models established could significantly reduce the cost, time and usage of water supply for field data collection using JEd.

Universities are considered to be similar to small towns because of their large size, large population, and various complex activities taking place on campuses (Alshuwaikhat and Abubakar 2008). As such, they not only need to maintain an appropriate physical infrastructure, physical infrastructure, but they also require services similar to those in small towns including accommodation, transport, retail, leisure, and, of course, solid-waste management.

Domestic waste‒composition investigation into different solid waste‒generation sources shows that the largest amount of domestic waste is generated at dormitories and faculties. Managing and controlling domestic-waste generation at dormitories and cafeterias has a significant effect of reducing organic waste and could reduce half of the total domestic waste. According to the comparison of recyclable materials generated from different sources, the results show that the most important sources of recyclable materials generation are dormitories because they generate 40 % of these materials follows by faculties, with 27 % generation. Therefore, dormitories and faculties are two hot spots in terms of recyclable-materials generation that should be considered. Comparing materials collected at the source and those existing in disposable waste shows that the greatest part of recyclable materials generated are transferred for disposal and more than 25 % could not be collected more than 25 % at the source. Furthermore, 3.6 tons of compostable waste, 1.6 tons of recyclable materials, and 1.9 tons of usable waste for the anaerobic-digestion method are generated per day. According to the solid-waste composition, some solid waste‒management scenarios were suggested, and they were compared using LCA and AHP. Combining of the life-cycle analysis (LCA) and analytical hierarchy process (AHP) results in the cluster-analysis method illustrates that scenario 5—by integration of 20 % RDF, 40 % composting, 20 % anaerobic digestion, and 20 % recycling—is the most appropriate solid waste‒management system.

An investigation on institutional waste was investigated at the pilot campus in the first step of the designing. In the next steps, a life-cycle assessment (LCA) and analytical hierarchy process (AHP) were carried out to assess the potential of environmental impacts and to consider the economic aspects of solid-waste management.

Various models have been introduced in solid waste–management systems with the capability to analyze, evaluate, or predict future outcomes. LCA is a necessary tool in evaluating the environmental load generated from an activity or a product by means of identifying and quantifying the energy and material utilized, the generation of solid waste emitted in to the environment, and the impacts of such.

River morphology involves the lateral migration of matters deposited by flowing water in the river channel across its floodplain. This is driven by the erosion along the river banks and point bar deposition over time. This paper presents a review on river morphology studies and its potential impact to the society. The reviewed studies include mathematical models and computer simulation such as FLUVIAL-11 and RVR Meander Package that are significant to illustrate a continuous research development on channel adjustment. The findings also shows that a lot more area can still be explored to aid the fundamental of understanding river morphology and that East Malaysia will provide a good platform for the researchers to investigate the lateral migration of a river due to its diversity environment.

Results of the domestic waste‒composition investigation for different categories of the campus are explained in this chapter. This includes faculties, dormitories, administrations, cafeterias, services, and residential buildings along with solid-waste generation by different types of electronic waste, construction waste, and garden waste.

Social and economic damages are the most important damages of the bridge failure. Stability problems of such structures against failure and the depth of the abutments are directly related to the amount of the adjusted scour. Economy, reliability and stability have been main concerns regarding designing abutment bridges enhanced preventing scouring. In this study a detailed comparison of the up-to-date works on scour at the bridge abutment are presented including all possible aspects and contraction scour depth estimation formulas. The experimental data was obtained from the literature and three statistical tests were carried out to determine which of the formulae would give minimum prediction errors. Statistical and graphical comparison between the predicted and measured depth of scour showed the better relatively acceptable prediction scour formulas depth at abutments.

Social and economical damages are the most important damages of the bridge failure. Stability problems of such structures against failure and the depth of the abutments are directly related to the amount of the adjusted scour. Economy, reliability and stability have been the main concerns on enhancing the designing of abutment bridges to prevent or reduce embankement scour. In this study a detailed comparison of the researches on scour at abutment bridge are presented including all possible aspects and scour depth estimation formulae. The experimental data for prediction the abutment local scour depth were investigated. Statistical and graphical analysis allow to recommend the most accurate formula in prediction scour depth at the abutment bridges. Availability of additional data and further analysis would allow promoting the bridge abutment design and decreasing the bridges’ construction and maintenance cost by increasing the accuracy of the footing depth design.

Bank erosion is commonly associated with river meandering initiation and development, through width adjustment and planform evolution. It consists of two types of erosion processes; basal erosion due to fluvial hydraulic force and bank failure under the influence of gravity. Most of the studies only focused on one factor rather than integrating both factors. Evidences of previous works have shown integration between both processes of fluvial hydraulic force and bank failure. Bank failure seldom treated as a probabilistic phenomenon without assessing the physical characteristics and the geotechnical aspects of the bank. Thus, the objective of this paper is to investigate factors governing streambank erosion process and to perform a dimensional analysis considering the physical characteristics of both processes namely fluvial erosion and mass failure and their interaction.

Erosion from riverbank is most properly represented by the erodibility factor. One of the methods that can be used for in situ soil erodibility testing is the submerged jet test called Jet Erosion Test (JET). In this study, a newly modified version of the JET device namely Jet Erosion Device (JEd) is fabricated, with improved features and design that facilitates testing in the field and the laboratory. Analysis and calibration of the JEd tests were conducted to check on the reliability and performance of the Jet Erosion Device (JEd). Some preliminary results were shown to give some insights on the capabilities of the JEd. An evaluation of the erosion performance index i.e. jet index was performed to characterize the erosion resistance. The estimation of erodibility coefficients were made using the results of jet index obtained.

A large number of studies both theoretical and experimental have been devoted to understand the physical mechanisms underlying the bar formation. This can be investigated by carrying out an experimental work in an erodible sand bed channel using a large-scale physical river model. The study included the various hydraulic characteristics with steady flow rates and sediment supply. An experimental work consists of four matrices of flow rate and channel width with other variables namely grains size and bed slope were kept constant. Details of bar profile development that generated using Surfer, a software used for 3D elevation plots are included.

Experimental studies on local scour at bridge pier are explored widely both theoretically and experimentally. There are many factors involved in the magnitude of local scour depth at piers such as velocity of the approach flow, depth of flow, size and gradation of bed material, and bridge pier itself. This paper presents a comprehensive review and highlights thus far in study of the effects of sediment discharge on local scour before and after the channel bend. Lately, the addition of many types of structures has extremely altered the morphology of river regimes, and caused major influence on the transport and deposition of sediment. During the unforeseeable circumstances such as river floods, extreme erosion, denudation of forest, and mass wasting at the upstream zone the scour hole can happen and can affect failure to the bridge pier. The development in the theoretical and laboratory findings on the effects of sediment discharge on local scour before and after the channel bend will be of importance to the science of river morphology as this contributes to the shaping of the river landscape for future studies.

Green Technology design practice is a new solution that must be applicable to preserve a nature and reduce the pollution. There are so much innovation could be use to in the development of the park to reduce the electricity use, eco-friendly and liveable for the community. This paper aims to exemplify an effort by a group of students, through multi-professional inputs, in designing for a city facility that can add more towards a liveable city for Tasik Biru Kundang, Kuang Selangor, Malaysia. © 2011 Published by Elsevier Ltd. Selection and peer-review under responsibility of Centre for EnvironmentBehaviour Studies (cE-Bs), Faculty of Architecture, Planning & Surveying, Universiti Teknologi MARA, Malaysia.

This paper presents the flood inundation model using a hydrodynamic approach for flood simulation. A Digital Elevation Model (DEM) for Damansara Catchment was developed and integrated into the InfoWorks River Simulation (RS) program. Hydrographic surveying activity was carried out to collect existing Damansara River cross-section. The 3D flood model was calibrated using the 26th February 2006 and 15th October 2008 flooding event data. The model was validated using the flooding event on 21st March 2007. This computer simulation results produced hydrograph that indicates the capability of the model in dealing with regional flood analysis for future usage in designing structural flood measures.

This study presented a flood estimation model for Johor River in Kota Tinggi watershed, Malaysia using HEC-HMS (Hydrologic Modeling System). Calibration and validation processes were carried out using different sets of data. Evaluation on the performance of the developed flood model derived using HEC-HMS yield a correlation coefficient R super(2) close to 1. The simulated Q sub(peak) are 150.9 m super(3) sec super(-1), while the observed Q sub(peak) for 10 years record (1997-2006) is 145.12 m super(3) sec super(-1). The percentage of error values are 4% and the performance of the developed flood model derived using the HEC-HMS with R super(2) value is 0.905. Based on these findings, it is suggested that the developed model using HEC-HMS can be used as a tool for estimating Q sub(peak).

A total of 346 sets of bed-load data obtained from the Kinta River, Pari River, Kerayong River and Langat River were analyzed using four common bed-load equations. These assessments, based on the median sediment size (d50), show that the existing equations were unable to predict the measured bed load accurately. All existing equations over-predicted the measured values, and none of the existing bed-load equations gave satisfactory performance when tested on local river data. Therefore, the present study applies a new soft computing technique, i.e. an adaptive neuro-fuzzy inference system (ANFIS), to better predict measured bed-load data. Validation of the developed network (ANFIS) was performed using a new set of bed-load data collected at Kulim River. The results show that the recommended network can more accurately predict the measured bed-load data when compared to an equation based on a regression method.

Soil erosion is undesirable natural event that causes land degradation and desertification. Identify the erosion-prone areas is a major component of preventive measures. Recent landslide damages at different regions lead us to develop a model of the erosion susceptibility map using empirical method (RUSLE). A landslide-location map was established by interpreting satellite image. Field observation data was used to validate the intensity of soil erosion. Further, a correlation analysis was conducted to investigate the "Receiver Operating Characteristic" and frequency ratio. Results showed a satisfactory correlation between the prepared RUSLE-based soil erosion map and actual landslide distribution. The proposed model can effectively predict the landslide events in soil-erosion area. Such a reliable predictive model is an effective management facility for the regional landslide forecasting system.

Both present experimental and previous historical data were used to develop the empirical model. Generally, the aim of this study to establish an empirical model of bar formation from the present experimental data and selected historical data. Statistical techniques using Multiple Linear Regression Analysis were employed for empirical model development and the selection of bar formation parameters were done based on the works of previous investigators. Validation of the newly developed empirical model was done by using a different set of historical data from selected laboratory studies. Model development involved selection of parameters through review of established models, dimensional analysis to check on the homogeneity of the model and statistical analysis. Derived empirical model has been validated using a different set of data from previous studies. Analysis confirmed that the empirical model derived using linear regression technique depicts the highest discrepancy ratio accuracy of 90% with Dds${D \over {{d_s}}}$ and BD${B \over D}$ as the most significant parameters that promote bar height formation.

Installing shunt capacitors in a radial distribution system can provide a lot of benefit to utility and users. There are many ways to install capacitors as long as the sizes do not exceed the original inductive reactive power of a system. But it is very difficult to determine the best locations and size of capacitors. In addition, the unbalance nature of distribution system make the placement becomes more complicated. Optimal placement of capacitor is a highly nonlinear optimization problem which requires discrete control variables. This paper proposed an artificial intelligence approach to obtain optimal total line loss reduction and total cost of capacitor while improving the voltage profile along the feeders. It was done by integrating the circuitry distribution model in SIMULINK with particle swarm optimization (PSO) technique constructed in MATLAB. The optimization process was done in two stage where the first stage is to determine the early optimal locations while second stage is to determine optimal sizes. A modified IEEE 13-bus three phase unbalanced radial distribution system is used to validate effectiveness of the proposed technique in solving the problem.

Disaster relief management is essential for various types of disasters such as terrorist attacks, hazardous materials, hurricanes and flash floods. Planning for disaster relief is important in rescuing victims with the involvement of many agencies and the public in managing the event. This is due to poor coordination, late assistance and uneven distribution of vehicles, food, and medical assistants. Time and cost are very important in disaster relief. The need for a proper disaster relief plan to overcome these issues is crucial. This paper presents a two tier solutions to relieve flood victims focuses on the evacuation. The first tier is to complete the task of vehicles assignment at the inundated area. Then, the routing of vehicles from inundated areas to relief centres. A discrete particle swarm optimization were employed and tested reflecting the fitness functions identified from each tier. The findings show that the two- tier solution provides good results for the evacuation plan.

Numerous data on bar formation have been accumulated yet the methods to predict bar geometry especially bar height are still insufficient. Objectives of this study to determine the trend in term of a significant difference of centreline bed elevation profile along the longitudinal distance. This can be investigate by carried out an experimental work in an erodible sand bed channel using a large-scale physical river model. The study included the various hydraulic characteristics with steady flow rates and sediment supply. An experimental work consists of four matrices of flow rate and channel width with other variables namely grains size and bed slope were kept constant. Analysis have included the discussion on a significant difference of centreline bed elevation profile along the longitudinal distance. As a conclusion the higher velocity in the smaller channel width have induced erosion of the banks that resulted in elevation increase while the larger flow rates have contributed to higher elevation.

Flood evacuation operations face a difficult task in moving affected people to safer locations. Uneven distributions of transport, untimely assistance and poor coordination at the operation level are among the main problems in the evacuation process. This is attributed to the lack of research focus on evacuation vehicle routing. This paper proposes an improved discrete particle swarm optimization (DPSO) with a random particle priority value and decomposition procedure as a searching strategy to solve evacuation vehicle routing problem (EVRP). The search strategies are proposed to reduce the searching space of the particles to avoid local optimal problem. This algorithm was computationally experimented with different number of potentially flooded areas, various types of vehicles, and different speed of vehicles with DPSO and genetic algorithm (GA). The findings show that an improved DPSO with a random particle priority value and decomposition procedure is highly competitive. It offers outstanding performance in its fitness value (total travelling time) and processing time.

An optimal evacuation route plan has to be established to overcome the problem of poor coordination and uneven distribution of vehicles before or during disaster. This article introduces the evacuation vehicle routing problem (EVRP) as a new variant to the vehicle routing problem (VRP). EVRP is a process of moving vehicles from a vehicle location to the potentially flooded area (PFA), and from PFA to relief center using a number of capacitated vehicles. This paper examines the application of a multi-valued discrete particle swarm optimization (DPSO) for routing of vehicles from vehicle location to PFA. A solution representation is adopted and modified from the solution of the shortest path problem (SPP) to accommodate this problem. Experimental results were tested based on the objective function of finding a minimum total travelling time using datasets from a flash flood evacuation operation. DPSO was found to yield better results than a genetic algorithm (GA).

This article proposes a discrete particle swarm optimization (DPSO) for solution of the shortest path problem (SPP). The proposed DPSO adopts a new solution mapping which incorporates a graph decomposition and random selection of priority value. The purpose of this mapping is to reduce the searching space of the particles, leading to a better solution. Detailed descriptions of the new solution and the DPSO algorithm are elaborated. Computational experiments involve an SPP dataset from previous research and road network from Malaysia. The DPSO is compared with a genetic algorithm (GA) using naive and new solution mapping. The results indicate that the proposed DPSO is highly competitive and shows good performance in both fitness value and processing time.