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  • Written by Mohd Afif Md Jamel Khir
  • Category: RESEARCH

Potential of Wind as an Alternative Energy in Perlis

The world has started to come to the realization that Mother Earth is slowly but surely running out of natural resources and therefore efforts have been doubled by scientists and researchers in seeking alternative energy resources to continue sustaining our lives on this earth.

One potential renewable energy source that has been developed rapidly since the late 1970s is wind power, which is generated through the creation of wind turbines. Capable of producing clean energy, without needing any fuel transport that are harmful to the environment, the wind, along with the sun and running water, are all sources of renewable energy. This is in contrast to coal, oil and gas, which rely on fossil fuels from mines or oil and gas fields that will one day run out of supply. 

Savonius wind turbineModern wind turbines are efficient, reliable and produce power at reasonable cost. As such, it has created a market for renewable energy as well as development in research. One of the developments is the technology in wind turbine. The control system have become cheaper and more advanced, new rotor blades which can extract more power from the wind were created, and the invention of new power electronic equipment makes it possible to use variable speed and to optimize the capacity of the turbines. In just a few decades, wind power has developed into a fast growing industry which no longer needs subsidies and is able to manufactures wind turbines that produce power at competitive cost. 

This paper plans to show the principle of work of vertical axis turbines, which is one of the several types of wind turbines available on the market, as well as to evaluate the potential of wind energy in Perlis. 

The energy conversion process of wind energy using wind turbines includes the rotation of blades that convert the wind energy into rotational mechanical energy on the shaft and to an electric generator. There are several different design concepts for wind turbines. One basic classification is the Horizontal Axis Wind Turbines (HAWT) and Vertical Axis Wind Turbines (VAWT). Vertical axis wind turbines are a type of turbine where the main rotor shaft runs vertically. The advantages of VAWT compared to the horizontal axis type of turbine are its simple construction, the lack of necessity of over speed control, the acceptance of wind from all directions, the limitation in mechanical design due to the control system and the electric generators that are set up statically on the ground. 

Darrieus wind turbineIn general, there are two distinctive types of VAWT, namely the Darrieus and Savonius types. For the Darrieus, there are three common blades which are Squirrel Cage Darrieus, H-Darrieus and Egg Beater Darrieus. The speed of wind speed for this paper is modeled using the Weilbull distribution.

 

 

Darrieus wind turbine

Savonius wind turbine

Advantages
  • High speed with low torque machine.
  • Generally requires manual push from external power source to start turning as the starting torque is very low.
  • Generator can be placed on the ground.
  • Easily integrated into buildings.
  • Slow rotating with high torque machine.
  • Shaft of the generator can be placed nearer to the ground.
  • Starts at low wind speed.
  • Low-noise system
  • Work with any wind direction.

Disadvantages
  • Difficult to self starting.
  • Need multiple wires.
  •  Low efficiency.

Another aspect of wind energy that this paper is looking into is the potential of utilizing wind turbines in the state of Perlis. According to Malaysian Meteorological Department, wind over this country is generally light with some periodic changes.

There are four seasons in Malaysia, namely the southwest monsoon, northeast monsoon, and two shorter period of intermoonsoon season. But, in Perlis, due to its close proximity to Thailand, the tendency is to the tropical monsoon season. The month of April, 2011 was chosen as the period of study for this paper.

The conclusion garnered from this paper is that the state of Perlis has the potential in developing the wind energy system. On the other hand, through the recording data from the use of vertical axis wind turbines, the results shows that this type of wind turbine is the most suitable to be used in Perlis as the wind speed in this state is low.

  • Written by Mohd Afif Md Jamel Khir
  • Category: RESEARCH

Productivity and Optimization of the machining mode of cutting tools

Metal shelving units are an economical substitute if you need storage space. The fact that they are built from metal and are far more flexible than wooden shelving is undeniably useful. The other substitute to metal is plastic shelving units, which is incomparably at a reduced cost than metal. However, compared to metal shelving units, these plastic units cannot carry so much weight.

Plastic units are not suited for rough handling which is crucial for all storage equipment to bear. Durability and impact resistance are the two most important things that we would not have to bother with metal units, causing industries and researchers to feel obliged to find an accurate calculation to increase the productivity rate during the metal cutting processes to optimize productivity.

Due to the increasing demands, researchers from UniMAP have taken initiative to find out the precise calculation to increase the productivity rate of the metal cutting machine. It is known that the strength of the machine operating modes reflects on the intensive wear of machine tool cutters to increase the dynamic forces, speed of the cutting process, and magnitudes of feed rates and the depth of cut.

The most unreliable elements, and yet one of the most important in a machining tools is the metal cutter itself. Comparing it to other components of machining tools such as spindles, bearings and sliders they are many times more reliable than metal cutters.

As a result, machine tools have to go through many cutters or blade replacement processes that ultimately affecting productivity and cost. However, the manufacturing industries are left clueless in between the processes as they are not able to estimates precisely the productivity rates due to the absence of the specific mathematical dependency.

However, researchers A.M. Ahmed Alwaise, R. Usubamatov and Z.M. Zain managed to come up with a mathematical equation to determine the productivity rate of an automatic machine tool on the change of processing mode.

The equation considers all the major aspects in calculating the productivity rate such as the total machine working time as in when it produces products as well as the time losses due to the failures of cutters, replacement, repairing and tuning.

The proposed equation of the productivity rate for automatic machine tool is a function of cutting speed and parameters of tool life, which enables calculations at the pre-stage of preparing economically effective manufacturing processes for products.

This finding enables industries to find the optimal processing mode that can give the maximum productivity rate of a machine tool. 

  • Written by Mohd Afif Md Jamel Khir
  • Category: RESEARCH

Statistical Study on Frequency Occurence among Kelantanese for Acute Leukaemia

The problem of cancer in Malaysia is a growing one. It is now the fourth leading cause of death among medically certified deaths. Leukaemia is cancer of the white blood cells. It is a malignant disease of the blood and the core of the bone.

When a person has leukemia, the bone marrow starts to make a lot of abnormal white blood cells, called leukemia cells. The cells don't do the work of normal white blood cells, they grow faster than normal cells, and they don't stop growing when they should. It is categorized as the uncontrolled accumulation of blood cells. Leukaemia will cause a patient to be extremely defenceless to life-threatening infections, due to the lack of white blood cells or uncontrolled and serious bleeding as due the short of platelets.

The majority of leukaemia patients are found at a late stage of the disease which at most of the times causes death. Statistics from National Cancer Council (MAKNA) adds that there are approximately 3567 new cases of childhood leukaemia each year. It is also estimated that the annual incidence of cancer is 30 000.

Cancer types

Rate per million

Leukemias

35.0

Tumors of the brain and spinal cord

13.9

Lymphomas

5.8

Neuroblastoma

4.9

Gonadal and germ cell tumor

4.1

Kidney

4.0

Soft tissue sarcomas

3.7

Retinoblastoma

3.6

Being aware of this phenomenon, a group of researchers from UniMAP and USM has taken initiative to look further into the frequency of occurrence for acute leukaemia by focusing on the citizens in Kelantan.

R. Adollah, M. Y Mashor, Rosline. H, N.H Harun, E. U Francis and Adilah. H gathered data from Hemathology Department, Hospital University Sains Malaysia, Kubang Kerian to analyze on the frequency of occurrence of ALL and AML pattern among the people of Kelantan by age group.

Leukaemia is divided into four categories, which are: Acute Lymphocytic Leukaemia (ALL), Chronic Lymphocytic Leukaemia (CLL), Acute Myelogenous Leukaemia (AML), Chronic Myelogenous Leukaemia (CML).

Acute leukaemia means the condition progresses rapidly and aggressively and requires immediate treatment while chronic leukaemia tends to progress slowly over the course of many years, therefore, in most cases does not required immediate treatment.

From the study, it can be seen that 55% of the samples have been diagnosed with ALL while another 45% has been diagnosed with AML where it shows general pattern for frequency occurrence in acute leukaemia. From the data, it shows that ALL is most commonly at age below 10 years old to 19 years old as for the age above 20, AML become more common. It can be said that AML is more common type of acute leukaemia among adults and ALL is commonly occurred in younger age. From the study, it can also be deducted that adults age 60 and older are more likely to develop leukaemia than younger people.

  • Written by Mohd Afif Md Jamel Khir
  • Category: RESEARCH

Red Blood Cells Image Segmentation and Classification: A Review

Rashid and his team, with the hope to aid the development of an automated system in screening or diagnosing biomedical images instead of just a prototype system, had collaborated to come up with a review on some of the current techniques and possibilities in image processing to be shared to other researchers.

In fact, automatic analysis of medical cell images is becoming more important in pharmacology and toxicology research. According to Rashid and his team, an automated analysis system would produce a more standardised automatic image analysis, which would conquer the current limitation of manual detection system. In addition, images will be mathematically defined with greater precision compared to the earlier images processing techniques. Thus, this would enhance and accelerate the analysis of image processing with high precision.

Rashid and his team chose to focus and review on some of the general segmentation and classification methods for red blood cell images, which are blood cells counting and segmentation of red blood cells. Blood count helps in detecting many diseases in early stage, whereas, segmentation helps in anaysing diseases and performing complete blood count (CBC) efficiently and it is cost effective.

Some of the recent types of methods in segmentation shared are:

  1. Thresholding -based on histogram characteristics of pixel intensities of image. 
  2. Morphological Operation –continuity-based techniques which involve the processing of shapes, to segment the red blood cell images
  3. Colour Image Segmentation –allow more reliable image segmentation than greyscale images and applying of hue feature. 
  4. Model-based contour tracing –to overcome the problem of automatically segmenting a Scanning Electron Microscope image of red blood cells that have high number of overlapping cells and relatively smooth contour. 
  5. Tabu Search –a method for finding elliptical cell boundaries.
  6. Matlab –to overcome the problem of counting overlapping red blood cells by applying new algorithm by using the method.
  7. Fluorescent Microscopy Images –can remove object with poor contrast and distance transformed watershed segmentation.

Some of the recent types of methods in classification shared are:

  1. Multilayer Perceptron –classifying various types of blood cells.
  2. Support Vector Machine –analyses data and recognize patterns which could be used for classification and regression analysis. 
  3. Learning Vector Quantization –a type of artificial neural network and can be applied to multi-classification problem is a natural way. E.g. in classifying blood cells and bone marrow

 

Studies of Geopolymerization Route For Metakaolin Geopolymeric Materials


Studies of Geopolymerization Route For Metakaolin Geopolymeric Materials

 

 

 


 

 

 

 

 

 


 
Investigation on production of metakaolin geopolymeric powder was aimed to increase the productivity and application of geopolymer products. Geopolymerization process was applied in the manufacturing of metakaolin geopolymeric powder to be used in geopolymer synthesis. Geopolymer slurry was made by alkaline activation of metakaolin in alkali activator solution (a mixture of NaOH and sodium silicate solutions). The geopolymer slurry was heated in an oven to produce pre-cured paste and then pulverized to get uniform particle size geopolymeric powder. By adopting the concept of “just add water”, the metakaolin geopolymeric powder was mixed with water and then oven-cured to produce resulting geopolymer pastes. The results showed that the optimum conditions for producing highest strength resulting paste are by using 8M of NaOH solution, solids/liquid ratio of 0.80, an activator ratio of 0.20, pre-curing of 80°C for 4 hours, 22% of mixing water and curing regime of 60°C for 72 hours. The resulting geopolymer pastes have low bulk density and were potential for a lightweight material. Upon the mixing of water with geopolymeric powder, densification of the structure occurred with the formation of compact geopolymer gels. The geopolymeric powder and resulting pastes showed the combination of amorphous and crystalline phases as analyzed by XRD. After ageing, the intensities of zeolites crystalline phases increased and this emphasized the benefit of zeolites in strength development of resulting pastes. This study clearly demonstrates that the production of metakaolin geopolymeric powder was able to be used in manufacturing geopolymer pastes.

Keywords: Geopolymer, powder, activator solution, geopolymerization, water