Ahmad Fariz Mohamed

Determination of Transmission Reliability Margin Using Parametric Bootstrap Technique

The determination of available transfer capability (ATC) must accommodate a reasonable range of transmission reliability margin (TRM) so that the transmission network is secure from uncertainty of transfer capability that may occur during a power transfer. This paper presents a computationally accurate method in determining the TRM with large amount of transfer capability uncertainty using the parametric bootstrap technique. The parametric bootstrap technique is used to randomly generate a bootstrap sample of ATCs with large uncertainty selected at a certain percentage of bootstrap confidence interval. The bootstrap sample of ATCs in a day is used to determine the TRM at every time interval. The TRM value at a particular time interval is selected based on a certain percentage of normal cumulative distribution function (CDF). Then, a new value of ATC at the current time interval is calculated by considering the TRM at the same time interval. The effectiveness of the proposed TRM method in providing new ATC value is validated on the Malaysian power system. The results show that the proposed method provides accurate estimation of TRM in which it is relatively similar to the TRM result obtained by the standard deviation of uncertainty which is incorporated in the Monte Carlo simulation technique. Further comparisons in terms of accuracy and total computational time in estimating the TRM is made between the parametric and nonparametric bootstrap techniques.

A case study of voltage sag analysis in a utility distribution system

Voltage sags are momentary dips in voltage magnitude that can cause sensitive equipments to trip. Such occurrences have a major economic impact and therefore, the study of voltage sag has become a major effort worldwide. This paper presents a voltage sag analysis implemented on an actual distribution system. The objective of the study presented in this paper is to develop a suitable method for voltage sag analysis in which the method is demonstrated on a practical distribution system. The voltage sag analysis is performed using the commercial software PSS/ADEPT for performing load flow and short circuit simulations. The distribution network is modeled using the actual network data and the transmission system is considered as a source. Faults are introduced at various points in the system, at the buses and along the lines. Simulation results are presented in the form of voltage sag vulnerability areas.

LCA for open systems: a review of the influence of natural and anthropogenic factors on aquaculture systems

PurposeLife cycle assessment (LCA) studies in the aquaculture sector have included marine fish, freshwater fish, and shellfish species within closed (CAS), semiclosed (SCAS), and open aquaculture systems (OAS). The absence of a physical boundary separating open aquaculture systems from natural ecosystems has caused complications in determining the actual environmental conditions of individual aquaculture systems and has resulted in questionable LCA impact analysis results. This paper reviews how natural and anthropogenic factors were managed in the previous LCA studies for aquaculture systems.MethodsTen recent peer-reviewed documents on the LCA study of various aquaculture systems have been selected for content analysis. The disparities between OAS, SCAS, and CAS were outlined. Natural and anthropogenic factors were then identified and analyzed to ascertain their impact on the LCA process.Results and discussionNatural factors such as seasonal variations, biological interactions, and flooding were indicated in the OAS, SCAS, and CAS. For anthropogenic factors, industrial energy inputs and human activities were stated in SCAS and OAS. None of the anthropogenic factors were considered in CAS as these systems are isolated distinctly from natural ecosystems. LCA studies of the OAS have a few approaches: the development of the virtual boundary, a longer period of data collection, harmonization with other environmental management tools, and the need to diversify the LCA study in various regions.ConclusionsFor SCAS and OAS, the interaction between the aquaculture system and flood hazards, temporal changes, dilution effects due to the seasonal variation, disease, and local anthropogenic activities can be studied further. An LCA study of OAS will be more reliable if natural and anthropogenic factors are seen as supportive variables in determining the life cycle impact analysis.

Waste Minimization Benefits and Obstacles for Solid Industrial Wastes in Malaysia

Moving toward a sustainable industrial activity requires an effective waste management that is applicable and efficient for all different types of industrial wastes .Waste minimization as the most acceptable option in waste management hierarchy, has a significant contribution in minimizing the solid wastes generated by manufacturing industries. The absence of appropriate policy, lack of awareness and information ,inadequate guidelines , limited time , lack of cooperation and application of old technologies such as end of pipe approaches are the common obstructive factors towards practicing efficient waste minimization by industries. The study was conducted to review and analyze the practical waste minimization methodologies and its characteristics based on the industrial activities. In addition the obstacles which hold up industries from practicing waste minimization efficiently were determined. Thus this study suggest the effective practices for improving waste minimization which suitable for manufacturing industries in Malaysia.

Health impact assessment from building life cycles and trace metals in coarse particulate matter in urban office environments

This study intends to determine the health impacts from two office life cycles (St.1 and St.2) using life cycle assessment (LCA) and health risk assessment of indoor metals in coarse particulates (particulate matter with diameters of less than 10µm). The first building (St.1) is located in the city centre and the second building (St.2) is located within a new development 7km away from the city centre. All life cycle stages are considered and was analysed using SimaPro software. The trace metal concentrations were determined by inductively couple plasma-mass spectrometry (ICP-MS). Particle deposition in the human lung was estimated using the multiple-path particle dosimetry model (MPPD). The results showed that the total human health impact for St.1 (0.027 DALY m-2) was higher than St.2 (0.005 DALY m-2) for a 50-year lifespan, with the highest contribution from the operational phase. The potential health risk to indoor workers was quantified as a hazard quotient (HQ) for non-carcinogenic elements, where the total values for ingestion contact were 4.38E-08 (St.1) and 2.59E-08 (St.2) while for dermal contact the values were 5.12E-09 (St.1) and 2.58E-09 (St.2). For the carcinogenic risk, the values for dermal and ingestion routes for both St.1 and St.2 were lower than the acceptable limit which indicated no carcinogenic risk. Particle deposition for coarse particles in indoor workers was concentrated in the head, followed by the pulmonary region and tracheobronchial tract deposition. The results from this study showed that human health can be significantly affected by all the processes in office building life cycle, thus the minimisation of energy consumption and pollutant exposures are crucially required.

Challenges of Ecosystem Resilience: An Aspect of the Sustainability Science Approach in the Study of Environmental Awareness in the Selayang Municipal Council, Selangor, Malaysia

This article discusses a conceptual framework for developing environmental awareness among the Malaysian people via sustainable development principles and the dialogic change model. The conceptual model was developed based on the principles of the integrated pillars in sustainable development and the dialogic change model. Two main component data were used: awareness campaign activities data and complaints data. The awareness campaign hard data were obtained from the various government agencies that contain the awareness campaign activities such as the Town and Country Planning Department (TCPD), the Department of Environment (DoE), and the Ministry of Health (MoH), among others, for the past 10 years (2005–2015). The complaints data were gathered from the Selayang Municipal Council (Majlis Perbandaran Selayang—MPS). Generally, people are more aware of the changes that take place in the urban ecosystems as the recipients of rules or policies made by authorities. The level of awareness among the Malaysian people now has improved. The people take action through the Municipal Council via telephone calls, face-to-face complaints and emails. This article uses the complaints by the residents in the MPS, which is located in the Selangor State, as a case study to investigate the level of awareness and actions taken by urbanites in urban areas. The main findings of the study are issues related to cleanliness of the resident’s area and maintenance, among others, and the major implications for planning policy and ecosystem resilience will be drawn in this article.

Understanding Waste Flow in Malaysian Cities for Sustainable Waste Management

Malaysian cities have undergone rapid growth over the past four decades. Cities such as Kuala Lumpur continues growing and its population have reached 1.67 million in 2015. As its population increases, a city’s metabolism process quickens, in turn, producing more waste as a by-product. The increasing rate of waste generation has become a critical issue for Malaysian cities, which generated 16,200 tons of waste per day in 2001 compared to 33,000 tons per day in 2012. Hence, managing the waste requires significantly more technological, financial, and human resources as well as land. There is now a need to understand the waste flow and to determine the key factors of sustainable waste management. This study was conducted to analyze factors such as waste generation patterns, technology, and infrastructure as well as the financial, legal, human resource, and waste management systems currently in place. The analyses conducted illustrate that these factors play an important part in controlling waste generation and flow. The findings from these analyses also provide key strategy for managing the waste flow in Malaysian cities such as Kuala Lumpur towards achieving sustainable waste management.

Managing the Growing Kuala Lumpur Mega Urban Region for Livable City: The Sustainable Development Goals as Guiding Frame

In the last three decades, Malaysia has witnessed fast urban growth and spatial spread at a rate never experienced before, in response to overlapping industrial, social, economic and policy drivers. The paper will analyse the urban spatial spread from the productive towns and cities in the country, in particular, taking the Kuala Lumpur mega urban region as focus to demonstrate the spread of urbanization surfaces and the dimension of modernity among the urban people associated with urban life. The approach taken is the framework of the sustainability science, specifying issues and then taking a transdisciplinary stance to those issues. Data were then gathered from published sources supported by our own field observations of urban land use spread in parts of the Kuala Lumpur mega urban region. Despite the increasingly glittering showcasing of the state of the art development in infrastructures, housing and economic diversity there are challenges that the Kuala Lumpur mega urban region has to pay attention to, to make the city livable. Looking beyond the physical achievements to date there remains to develop what has been discussed lately about grooming the soul of the city, to instil the urbanites with globally accepted values related to what we believe should be the essence of a livable city, such that the urbanites will take responsibility to be with the authority to ensure, for example, cleanliness, safety and making the city more vibrant and attractive.

Spatial analysis of development pressure in the Langat Basin, Selangor, Malaysia

The process of globalization and urbanization is growing rapidly in Southeast Asia. In Malaysia, one of the fastest growing areas is in Langat Basin, Selangor. Outrageous process the city to the periphery is now growing towards the southern corridor. This article discusses the use of geographical information system to spatially analyze the development of the built-up area in the north of Selangor. The purpose is to identify areas experiencing high-intensity development. The development of the built-up area has affected the environment, society and economic development of the area. The result shows rapid development has increased pressure to the Langat basin since the 1990s. In 1996 the built-up area is about 23017.8 square km. It had increased to 119587 sq km in 2016. This shows that developed areas had increased 40.70% over the period of 20 years from 1996 to 2016. This indicates that the area has been experiencing high development pressure over the period. More importantly, the pattern of urban development was not evenly distributed throughout the study area. This situation needs to be addressed so that rural area is protected from further development pressure.

Toward sustainable solid waste minimization by manufacturing firms in Malaysia: strengths and weaknesses

Malaysia is facing an increasing trend in industrial solid waste generation due to industrial development. Thus, there is a paramount need in taking practical actions and measurements to move toward sustainable industrial waste management. The main aim of this study is to assess practicing solid waste minimization by manufacturing firms. Analysis showed that majority of firms (92%) dispose of their wastes rather than utilize other sustainable waste management options. Also, waste minimization methods such as segregation of wastes, on-site recycle and reuse, improved housekeeping, and equipment modification were found to have significant contribution to waste reduction (p < 0.05). Lack of expertise (M = 3.50), lack of enough information (M = 3.54), lack of equipment modification (M = 3.16), and lack of specific waste minimization guidelines (M = 3.49) have higher mean score comparing with other barriers in different categories. These data were interpreted for elaborating on SWOT and TOWS (strengths, weaknesses, threats, and opportunities) matrix to highlight strengths, weaknesses, threats, and opportunities. Subsequently, ten policies were recommended for improvement of practicing waste minimization by manufacturing firms as the main objective of this research.