The role of socio-economic and cultural factors in municipal solid waste generation: a case study in Taman Perling, Johor Bahru

The absence of a comprehensive database on solid waste generation and composition appears to be the major drawback to the development of an integrated waste management system in Malaysia. While many studies have been conducted on related fields, such as Abd. Karim et al. (1996), Sabarinah (1997), and Salim et al. (1994), there is still a lack of clear model or approach in determining attributes influencing the amount of wastes generated by our community. A study conducted in Taman Perling, Johor Bahru has shown that such as attributes as income, education, and other socioeconomic factors barely affect the amount of waste generated. It seems that only family size and lifestyle factors, particularly the eating habits of residents, contribute significantly to variations in the generation of residential waste in the study area. While the amount increases with the size of family, it decreases as the respondents dine out more often. This study suggests new insights concerning the role of social factors and lifestyle in affecting the generation of household waste

The importance of usability features in enhancing online communication satisfaction

Web 2.0 is providing more responsive, interactive and online platforms of participation and engagement within users in organizations. The growth of the Internet gives a significant contribution to the development of online systems. The acceptance and usage of online system in organizations depend on various key factors such as ease of use, interactivity and usability. This study evaluates the importance of usability of online information management systems (IMS) in the context of user attitudes to online communication satisfaction which drives usage. Based on a survey of 223 employees at four research universities in Malaysia, this study adapted the communication satisfaction and usability to examine the online satisfaction in using IMS. The results indicate that there is a positive and significant relationship between usability and online communication satisfaction toward IMS usage. This study reveals the importance of usability in understanding the requirements in improving communication satisfaction, especially in developing online systems

Multi-agent reinforcement learning for route guidance system

Nowadays, multi-agent systems are used to create applications in a variety of areas, including economics, management, transportation, telecommunications, etc. Importantly, in many domains, the reinforcement learning agents try to learn a task by directly interacting with its environment. The main challenge in route guidance system is to direct vehicles to their destination in a dynamic traffic situation, with the aim of reducing travel times and ensuring efficient use of available road network capacity. This paper proposes a multi-agent reinforcement learning algorithm to find the best and shortest path between the origin and destination nodes. The shortest path such as the lowest cost is calculated using multi-agent reinforcement learning model and it will be suggested to the vehicle drivers in a route guidance system. The proposed algorithm has been evaluated based on Dijkstra's algorithm to find the optimal solution using Kuala Lumpur (KL) road network map. A number of route cases have been used to evaluate the proposed approach based on the road network problems. Finally, the experiment results demonstrate that the proposed approach is feasible and efficient

The characteristics of the Computer Supported Collaborative Learning (CSCL) through Moodle: a view on students’ knowledge construction process

Computer Supported Collaborative Learning (CSCL) is based on the pedagogical process of observation where students will learn progressively through active group interaction. CSCL is an emerging branch of the learning sciences concerned with studying on how people can learn together with the help of computers. Thus, this research was conducted to measure the characteristics of the CSCL learning environment through Moodle that assists the process of students’ knowledge construction during the teaching and learning process. The CSCL learning environment is an educational learning system which develops to help the teachers and students in managing School Based Assessment (SBA) in selected secondary school in Malaysia. Samples involved two groups of students and two Technical and Vocational Education and Training (TVET) teachers from two different schools. A total of 61 students, who were taught using CSCL approach through Moodle, underwent the process of teaching and learning using their school computer laboratory. The finding shows that the characteristics of the CSCL learning approach that used in this learning environment for the first group are at a high level with overall mean of 4.17 and the second group at moderate level with overall mean of 3.62. The result proves that the characteristics of the CSCL learning environment help students to build their knowledge during teaching and learning process at the high level with an overall mean score of 3.87. The mean of these two groups may vary according to students’ background, as well as learning environment facilities. Although, CSCL leads to students’ self-development, improving learning quality, sharing knowledge and assisting students’ in the process of building their knowledge, implementation of CSCL must first considering the technology relevant facilities, especially computer laboratory and internet accessibility in school. The implication is that designing a good CSCL must also taking into account the targeted users’ cultural background and socioeconomic factor

Heat transfer to Liquid Nitrogen Droplets during Cyrogenic Freezing of Foods

This work investigates the heat transfer phenomena that occurs when liquid nitrogen droplets fall onto a food surface. A gelatin slab was used as the food material. Liquid nitrogen was dropped on it from a dropper/reservoir system. The temperature of the slab and the droplet evaporation time were measured over a period of time. The heat transfer coefficients were calculated from these values. These are compared with the theoretical predicted values. It is seen that the experimental values are three to four times higher than the predicted values. However, if the average value of heat transfer coeff£c£ent is taken over the whole size range as the droplet evaporates, a closer agreement is obtained - the experimental values being less than twice higher

Contemporary environmental issues of landfill leachate: assessment & remedies

AbstractLandfills are the primary option for waste disposal all over the world. Most of the landfill sites across the world are old and are not engineered to prevent contamination of the underlying soil and groundwater by the toxic leachate. The pollutants from landfill leachate have accumulative and detrimental effect on the ecology and food chains leading to carcinogenic effects, acute toxicity and genotoxicity among human beings. Management of this highly toxic leachate presents a challenging problem to the regulatory authorities who have set specific regulations regarding maximum limits of contaminants in treated leachate prior to disposal into the environment to ensure minimal environmental impact. There are different stages of leachate management such as monitoring of its formation and flow into the environment, identification of hazards associated with it and its treatment prior to disposal into the environment. This review focuses on: (i) leachate composition, (ii) Plume migration, (iii) Contaminant fate, (iv) Leachate plume monitoring techniques, (v) Risk assessment techniques, Hazard rating methods, mathematical modeling, and (vi) Recent innovations in leachate treatment technologies. However, due to seasonal fluctuations in leachate composition, flow rate and leachate volume, the management approaches cannot be stereotyped. Every scenario is unique and the strategy will vary accordingly. This paper lays out the choices for making an educated guess leading to the best management option

Numerical solution of SOR iterative method for fuzzy Fredholm integral equations of second kind

In this paper, we deal with the application of Successive Over-Relaxation (SOR) iterative method for solving fuzzy Fredholm integral equations of the second kind (FFIE-2). In addition to that, we apply the trapezoidal rule to derive the approximate solution of FFIE-2 which consists of a system of integral equations. Next, the approximate equation is used to develop a system of linear equations. Then, we consider SOR iterative method to solve the generated system of linear equations. Next, SOR iterative method is implemented on some numerical examples. Finally, the numerical results is discussed in details by comparing the number of iterations, the computational time, and the Hausdorff distance to analyze the performance of proposed method. Based on the numerical results obtained from all the numerical examples by using Gauss-Seidel (GS) and SOR methods, it can be pointed out that SOR method is more efficient than the GS method

Effects of operating parameters on the performance of washing–electrokinetic two stage process as soil remediation method for lead removal

The application of washing-electrokinetic two stage process on remediation of lead (Pb) contaminated soil was investigated. The process consisted of an initial soil washing, followed by an electrokinetic process. The use of electrokinetic process in soil washing could provide additional driving force for transporting the desorbed Pb away from the soil even in the absence of pore flow. Thus, high usage of wash solution may be mitigated. In this study, the effect of operating conditions such as electric potential difference, wash solution concentration and initial Pb concentration on the feasibility of washing-electrokinetic two stage process on Pb removal was investigated using response surface methodology based on Box-Behnken design. The wash solution used was citric acid and three main aspects were examined, namely: (i) removal efficiency, (ii) effluent generated, and (iii) power consumption. The results revealed that the increase in electric potential difference and wash solution concentration generally enhanced Pb removal efficiency and the interactions of these parameters were significantly positive. However, undesirable high effluent generation and power consumption were also caused by these increments. Optimisation study revealed that 84.14% removal efficiency with zero effluent generation and a power consumption of 2.27 kW h/kg Pb removed could be achieved at 7.58 V and 0.057 M citric acid concentration. In comparison with normal soil washing, washing-electrokinetic two stage process showed an enhancement in removal efficiency by approximate to 16% via electromigration under optimum conditions using similar solution: soil ratio of <0.8 mL:1 g soil. The study reveals that incorporation of electrokinetic process in soil washing is feasible as it not only enhances Pb removal efficiency at minimum wash solution usage with respect to normal soil washing, but also provides in situ Pb recovery in cathode chamber via electrodeposition. (C) 2015 Elsevier B.V. All rights reserved

Distributed power control and beamforming for cognitive two-way relay networks using a game-theoretic approach

This paper studies a cognitive two-way relay network in which multiple pairs of secondary users (SUs) exchange information with the help of multiple relays. We propose a distributed power control and beamforming algorithm that enables the users operating in the underlay mode to strategically adapt their power levels, and maximize their own utilities subject to the primary user (PU) interference constraint, as well as its own resource and target signal-to-interference-and-noise-ratio (SINR) constraints. The strategic competition among multiple decision makers is modeled as a non-cooperative game where each secondary user (SU) acts selfishly in the sense of maximizing its own utility. An adaptive method is proposed to determine appropriate pricing function. The problem of beamforming optimization under amplify-and-forward (AF) protocol is addressed as a generalized eigen value problem with respect to the utility function of SUs. The existence of a unique Nash equilibrium (NE) is proved and several numerical simulations are conducted to quantify the effect of various system parameters on the performance of the proposed method

SOR Iterative Method with Simpson’s 1/3 Rule for the Numerical Solution of Fuzzy Second Kind Fredholm Integral Equations

In this study, we present the application of Successive Over-Relaxation (SOR) iterative method to solve fuzzy Fredholm integral equations of the second kind (FFIE-2). In addition to that, the Simpson’s 1/3 quadrature rule is applied to derive the approximate solution of FFIE-2. Then, we use the approximate equation to generate a system of linear equations. Next, SOR iterative method is introduced to solve the generated system of linear equations. Moreover, we conduct some numerical examples to illustrate the applicability of the SOR iterative method. Finally, we discuss the efficiency of the proposed method by comparing the number of iterations, computational time and Hausdorff distance. Based on the numerical results, we conclude that SOR method is better than Jacobi and Gauss-Seidel iterative methods