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Mangrove gastropods as biomonitors for heavy metal contamination / Farhathul Manas
No full textA process called biomonitoring can be used to analyze the factors that affect the ecosystem. In this study, gastropods and sediments were used to observeits impact on the study sites under the Klang Islands Mangrove Forest Reserve (KIMFR): Pulau Klang (Klang Island), Pulau Carey (Carey Island) and Telok Gong representing the natural mangrove, agricultural and industrial environments, respectively. Environmental monitoring was performed using gastropods and sediments that were collected and tested for heavy metals including arsenic (As), lead (Pb), cadmium (Cd), and mercury (Hg). The inductive coupled plasma mass spectrometry (ICP-MS) was used for heavy metal testing in gastropods whereas inductive coupled plasma optical emission spectrometry (ICP-OES) was used for sediment. The gastropods collected were observed to identify their species composition and abundance, and correlate heavy metals with the species. Telok Gong was found to be more diverse with nine species, followed by Carey Island and Klang Island with eight and five species respectively. Klang Island had less species richness, but more abundance. Ten gastropod species was discovered from the study sites: Nerita lineata, Cerithidea quadrata, Chicoreus capucinus, Telescopium telescopium (TG, KI & CI), Cassidula aurisfelis (TG & KI), Ellobium aurisjudae, Littorina scabra, Littorina melanostoma (TG & CI), Thais tissoti (CI), and Cerithidea cingulata (TG). Due to a scarce in availability and size, only six species were selected for heavy metal testing: Chicoreus capucinus, Telescopium telescopium, Nerita lineata, Cassidula aurisfelis, Cerithidea quadrata, and Ellobium aurisjudae. Concentration results of heavy metals from the separation of gastropod body and shell showed that As and Hg were more concentrated on the gastropod body whereas Cd and Pb were concentrated on the gastropod shell. Chicoreus capucinus showed a high concentration of As whereas Ellobium aurisjudae showed a higher concentration of Cd compared to other species. Cassidula aurisfelis showed a higher concentration of Pb where as Telescopium telescopium showed higher a concentration of Hg. It was assumed that these species could be used as biomonitors for specific metals. However, each species has its own ability to retain heavy metals hence, future studies for specific metals and gastropods should be conducted to confirm the species’ effectiveness as biomonitors. The heavy metal comparison showed As and Pb were more concentrated in sediments than in gastropods. However, the concentrations of Cd and Hg were similar which were < 0.5 μg/g in both gastropods and sediments. This may be due to the metals’ affinity towards the samples. The data comparison for the locations showed that Telok Gong had higher concentrations of As and Pb in both sediment and gastropod because it is surrounded by industries. However, Pb detected in gastropod at Klang Island showed higher value than Telok Gong. Sediment quality index (CBSOG SQG (2003) showed moderate pollution of As at Telok Gong and low pollution at the other sites. The values of Cd, Pb and Hg were relatively low for the three sites. The noticeable amount of As and Pb in gastropods indicate that the sites were polluted from adjacent areas like industries and shipping ports
In vivo morphogenesis and in vitro regeneration of Crocus sativus L. / Nordiyanah Anuar
No full textThepresent research aimsto investigate the morphogenesisof CrocussativusL.grownin vivo andalso in vitroregeneration of this valuable crop forthefirst timein Malaysia.Duringin vivostudies, temperatureand growing substrateswereproven to significantlyaffect the growth performanceof C. sativuswhetherduring thevegetative or floweringphases. C. sativusrequiredaspecifictemperaturesetting and developed best in asequenceofhigh temperatureduring corm germination to lowertemperatureduringflower initiation. Theoptimumtemperatureforflower formation was at 16°Cprovidedthat the corms weregerminated at ahigher temperaturein therangeof 23°Cto 30°C. A very low temperature(10°C)during the dormancy stage, hamperedthe next stageofflower formation. This studyalso revealedthat C. sativuswas very wellgrownin 100%vermiculite as the plants produced biggercormlets with diameterof morethan 2.5 cmwith amean weightof 6.17 ± 0.11g.Thefloral phases of C. sativus though had limited references, was successfully described in detail in the present studywherebyunderfavourabletemperatureand best-growing media, the floral phaseslasted about 9 daysstartingfromthe beginning of flower cataphyll (BBCH51)until the end of flowering (BBCH69). At the full flowering stage (BBCH65), C. sativushad the greatest amount ofanthocyanin (257.33 ± 0.28 mg/100g) and the longest stigmas (3.64 ± 0.05 cm)for high yield recovery.An efficient in vitroregenerationprotocol was also successfullydeveloped for C. sativus via direct regeneration and somaticembryogenesis. Corm explant was the mostresponsiveexplant for direct regeneration and exhibited the optimumregenerationcapabilityin Murashigeand Skoog (MS)mediasupplemented with combination of 3 mg/l6-benzylaminopurine(BAP)and 1 mg/l naphthaleneaceticacid(NAA), while sprout and leaf explants failedto formcomplete plantlet.Complete regeneration with microcormletswas also achieved from whole, small-sized corm explant in the combination of 0.5 mg/l BAP and 0.5 mg/l NAA with anaverageof 5.73± 0.21 shoots,3.27 ±0.13 roots and 2.23 ± 0.10 microcormlets.In vitroflowering of C.sativus, though seldomlyreported in the literature, was achieved underinfluenceof 0.5mg/l triacontanol (TRIA)with 20%regeneration frequency. Somatic embryogenesiswas successfully established from corm-derived callusunder influenceof0.5 mg/lBAPwith maximum numberof microshoots (9.97 ±0.29)even though the earlier embryoproliferation phaseshowed moderatecallus multiplicationrate. Thecallus-derivedmicroshoots also yielded the optimumpercentageof microcormlets (83.33 ± 6.92%) with theaddition of 40 mg/l adenine sulphate(AdS). Theplantlets withmicrocormletswereacclimatizedin vermiculiteanddisplayed normal phenotypesimilar tothe motherplant. As saffron is ahighly expensive spiceproduced by C. sativus, in vitroregeneration protocols developed inthis studyalong withthein vivomorphogeneticproperties,has laid afoundation forfurther studies to develop appropriate technologyfor its commercial cultivation in Malaysia
Stress analysis of mechanical seal in API 610 pump / Balqis Erizy Zainal
No full textThis research project uses Ansys Finite Element Analysis software to conduct Stress Analysis of Mechanical Seal used in API 610 pump. Maximum Sealing Pressure will be
applied as per API682 requirement and maximum and minimum stress will be monitored. The finite element method has become a powerful tool for the numerical solutions of a
wide range of engineering problems. Besides equivalent stress, strain and deformation of the mechanical seals will also be analyzed. The modeling of the mechanical seal was done by Ansys Design Modeler and the analysis was performed by using Ansys workbench 2021 R1 version. In the model, the mechanical seal face parts are going to be in contact and the remaining parts like ring and steel support not combined. At the end of research, we will be able to select the best candidate for the critical part of mechanical seal in API 610, which is the sleeve part
Computational fluid dynamics simulation of rotor cooling system in interior permanent magnet motor / Muhammad Amirul Asri Ahmad Lukman
No full textThis study presents a interior permanent magnet (IPM) motor using rotor cooling to enhance the cooling system of the motor. The IPM motor applies the forced cooling method where channels were provided in the entire motor from its’ housing to the rotor through the designated paths in the cooling system. This designated paths consists of upper housing, housing jacket, lower housing, and hollow shaft. With the cooling system circulation inside the IPM motor, an effective cooling can be achieved as compared to the conventional approach of cooling. A modified coolant path is designed for optimization with different coolant used between water and oil. Once the cooling boundary was selected, the numerical model of the Motor Housing Cooling System of the IPM will be modelled and simulated. Temperatures at different locations of different coolant path design and coolant medium of water and oil were modelled and the numerical results is presented. After iterations, Case 1 suggests oil as a better cooling medium. However, in Case 2, the manipulation of motor housing of the coolant path itself influence the cooling effect and suggests the same cooling effect can be achieved at midpoint of the housing coolant path. Although the outlet of Case 2 suggests a lesser cooling effect, this finding where the improved housing coolant path opens the possibility of further study towards a better understanding of the characteristics of the cooling effect and finally optimize by saving on oil consumption whilst optimizing the pattern of the coolant path
Design and development of an image-guided vision system for robotics palletizing / Mohamad Zaid Mohamad Zaihirain
No full textThe ever-evolving trend in modern manufacturing techniques has led to a shift from the conventional method to the heavily automated manufacturing process. Modern intelligent technologies are being used to simplify, accelerate, and improve the quality of traditional manufacturing methods. Automation of production lines through robotic implementation can improve the manufacturing performance while lowering the associated costs because it helps standardize the stacking and palletization procedures. Current automation on palletizing system relies heavily on a predetermined sorting system due to its inability to detect irregular-shaped object. A vision system is needed to increase the flexibility of the robotic palletizing system by detecting the type of object and its orientation. To this end, this project aims to design and develop an image-guided vision system through the application of YOLO object detection and OpenCV for small-scale robotics palletizing of non-uniform shaped object, i.e., 3D printed chicken wings and drumsticks. A YOLO object detection model is trained using 5000 images containing the chicken wings and drumstick. This object detection model is then used to determine the type of object. Then, this information on type of object is used along with an orientation detection program to find each object�s orientation. The orientation detector is programmed with a contour detector called �Canny Edge detector� and a �fitEllipse� function that generates the angle of orientation. Using the location and orientation information generated by the detection programs, a pick and place operation is simulated in RoboDK. Through several case studies, this detection models works great if the objects in the images are arranged in a certain way, i.e., not closely packed together, or overlaps onto one another. In an ideal case, the pick and place simulation work flawlessly with the information obtained from the YOLO object detection and orientation detection progra
Design of low power, high linearity down-conversion CMOS mixer for industrial, scientific and medical applications at 900 MHz / Lai Chi Yi
No full textIn the tremendous growth of wireless application, low voltage and low power consumption with high linearity become a major consideration in radio frequency integrated circuit (RFIC). The development of a low power RF transceiver is driven in the demand of withstanding longer battery life and reduced cost to move towards mobile application. The continuous downscaling of CMOS technologies to reduce overall power consumption and high speed operation imposes design challenges in the construction of RF front end blocks, which creates an environment where circuits requires lesser voltage headroom to operate. This has driven the need in exploration of new low voltage and high linearity design technique for RF architecture. Often folded cascode topology is preferred over series stacking topology due to voltage headroom limitation. This work proposes new design and implementation of low voltage and low power down-conversion mixer with high linearity in 0.13?m standard CMOS technology for 900 MHz ISM applications. The proposed mixer performs frequency translation from a 900 MHz input radio frequency (RF) signal to a 100 MHz output intermediate frequency (IF) signal referring to a 800 MHz LO signal. The down-conversion mixer have been fabricated in Global Foundry 0.13 ?m CMOS technology. A suitable test bench is developed to measure the major performance parameters of the proposed design. At 1.0 V supply voltage, the mixer consumes 2.4 mW of power. Measurement results show 17 dB conversion gain (CG), 10 dB noise figure (NF), 11.3 dBm third-order intercept point (IIP3), and port-to-port isolation greater than 50 dB. A study on various Figure-of-Merit was conducted and a suitable Figure-of-Merit was selected to better characterize the proposed design
Climate capitalism and state-owned enterprises (SOES): Case studies of FELDA and FGV palm oil sector / Vignaa Ganesan
Get PDFNeoliberalism is often seen as incompatible with sustainability objectives, as profit-seeking firms are expected to overlook climate and environmental concerns in their pursuit to generate revenue. However, the climate capitalism model argues that profit and sustainability goals are not necessarily incompatible. It posits that, under favourable market and governance conditions, private firms can be empowered to shift to more sustainable practises while profiting from this change. Many policymakers have embraced this model as a way to address environmental problems within the context of maintaining existing power structures and for continued economic growth. However, the climate capitalism model has overlooked an important point: a large segment of firms involved in climate-intensive sectors are not private firms. In many natural resource-rich countries, state-owned enterprises (SOEs) control these resources. Hence, this thesis questions the applicability of the climate capitalism model within the context of SOEs. There are many types of SOEs, with different ownership and control structures, which translates to a different emphasis on profit. Therefore, this thesis asks the question: do ownership and control structures of different types of SOEs influence their decision-making processes on the environment? To illustrate this, the thesis uses a case study approach comparing two types of SOEs within the climate intensive palm oil sector: the people-oriented FELDA and the profit-oriented FGV. Despite similar market and governance conditions, the decisions taken by these SOEs resulted in opposite outcomes for the environment. FGV, with an ownership and control structure dominated by state and private investors, tended to take advantage of this structure to overlook environmental objectives in the pursuit of profits. On the other hand, FELDA, which is owned and controlled by the state and settler cooperatives, achieved both capital accumulation and environmental protection through environmentally- and socially_conscious decision making. Hence, even when market and governance conditions are favourable, as in the case of both FELDA and FGV, the ownership and control structures of a firm can influence decision-making to either be positive or negative for the environment. Therefore, this thesis highlights the limitations of the climate capitalism model in predicting the environmental outcomes of neoliberal-type (profit_oriented) SOEs. While its principles may be applicable for most private firms, climate capitalism overlooks the fact that the market is made up of many different types of firms with a variety of ownership and control structures, which can affect firms' decision_making processes. In a world where SOEs control a significant proportion of climate_intensive sectors, there is an urgent need for this influential model to be reconceptualized to accommodate SOEs and other types of firms, to better offer solutions for environmental problems to be addressed within the context of existing institutions, power structures, and continued economic growth
Penilaian kemahiran kognitif bagi pembangunan modal insan: Kajian perbandingan dalam kalangan pelajar sekolah rendah antara Malaysia dan Brunei / Afiza Akashah John
Get PDFPembangunan modal insan merupakan satu komponen penting yang tidak dapat disangkal lagi peranannya dalam memajukan ekonomi sesebuah negara. Menurut teori modal insan terkini, kemahiran kognitif merupakan elemen penting yang perlu dititikberatkan dalam penilaian kualiti modal insan sesebuah negara. Maka, kajian yang dijalankan ini merupakan satu langkah proaktif ke arah membentuk satu pengkalan data yang baharu bagi negara untuk memantau pencapaian serta perkembangan kognitif pelajar. Kajian ini dijalankan bagi mencapai matlamat utama iaitu untuk mengkaji dan menganalisa pencapaian kemahiran kognitif yang merangkumi tahap penguasaan bagi setiap domain kognitif serta pencapaian akademik pelajar, mengikut faktor jantina (lelaki dan perempuan), dan perbandingan antara dua negara (Malaysia dan Brunei Darussalam). Kajian ini juga bertujuan untuk mengkaji perhubungan antara pencapaian kemahiran kognitif dan pencapaian akademik pelajar. Sampel kajian yang dipilih untuk kajian ini adalah dalam kalangan pelajar sekolah rendah yang berumur 9 sehingga 12 tahun daripada kedua-dua negara. Dengan jumlah pelajar yang terlibat daripada Malaysia sebanyak 1006 orang dari 8 buah sekolah dan 517 orang dari 4 buah sekolah dari negara Brunei, menjadikan jumlah keseluruhan pelajar yang terlibat adalah sebanyak 1523 orang pelajar daripada 13 buah sekolah. Penyelidik menggunakan kaedah ujian bagi meninjau pencapaian pelajar dalam tujuh domain utama kognitif iaitu Kemahiran Logik dan Penaakulan, Kemahiran Penyelesaian Masalah, Kemahiran Mengira (Matematik), Kemahiran Ingatan, Kemahiran Pemprosesan Visual, Kemahiran Perhatian (Penumpuan) dan Kemahiran Pemprosesan Perkataan/Ayat. Data yang diperoleh daripada kajian ini telah dianalisis dan ditafsir dengan menggunakan perisian Predictive Analytics SoftWare (PASW) 20.0. Merujuk kepada perbandingan antara negara, analisis data adalah signifikan (p < 0.05). Hasil kajian menunjukkan bahawa pencapaian purata skor kemahiran kognitif pelajar dari negara Brunei mengatasi pelajar Malaysia. Manakala dari segi perbandingan antara jantina pula, analisis data adalah signifikan (p < 0.05). Pelajar perempuan dilihat mendominasi pelajar lelaki dalam pencapaian kemahiran kognitif dan pencapaian akademik. Hasil kajian menunjukkan bahawa terdapat kesan interaksi yang signifikan (p < 0.05) bagi faktor jantina dan negara terhadap tahap penguasaan pelajar dalam enam domain kognitif yang dikaji kecuali domain kognitif Kemahiran Mengira. Seterusnya, berdasarkan analisis korelasi separa yang dijalankan, terdapat hubungan korelasi positif yang sederhana (r = 0.68 , p < 0.05) antara pencapaian kemahiran kognitif dan pencapaian akademik pelajar. Nilai r² sebanyak 0.46 menunjukkan bahawa 46% daripada pencapaian akademik pelajar adalah disebabkan oleh pencapaian kemahiran kognitif mereka, manakala, sebanyak 54% adalah disebabkan faktor-faktor lain. Berdasarkan graf plot selerak pula, didapati bahawa terdapat beberapa kes pencapaian akademik pelajar yang tidak selari dengan pencapaian kemahiran kognitif mereka. Hal ini jelas menunjukkan bahawa kaedah penilaian pelajar melalui pencapaian akademik semata-mata tidak dapat memaparkan potensi sebenar pelajar terutama dari segi tahap penguasaan kemahiran kognitif mereka. Justeru, dalam usaha untuk meningkatkan kualiti modal insan, setiap negara perlu memiliki kaedah penilaian pelajar yang tersendiri iaitu penilaian kemahiran kognitif bagi mengukur keberkesanan sistem pendidikan sedia ada selain dapat menilai perkembangan serta keupayaan pelajar dari segi kognitif mereka. Peningkatan kemahiran kognitif pelajar akan dapat menyumbang kepada penjanaan modal insan yang berkualiti yang dapat memacu kemajuan ekonomi sesebuah negara
The development of new crescent moon visibility criteria using circular regression model / Zuhaili Mohd Nasir
No full textThe lunar crescent moon visibility has a long research history since Babylonian Era. It is important in determining the local Islamic calendar and setting the dates of important Islamic events. The possible visibility of the crescent moon is dependent on a few criteria used during the sighting process. The methods to determine minimum condition or criteria for crescent moon visibility based on the linear statistical theory that have so far been developed are not that suitable for this study because the useful variables are in the circular unit. Thus, new visibility tests are proposed in this research using the circular regression model, which will divide the data into three visibility categories; visible to the unaided eye, may need optical aid and not visible. Using the residuals of the fitted circular regression model, we formulate the method for separating the categories. We apply the model on 254 observations collected at Baitul Hilal Teluk Kemang Malaysia, starting from March 2000 to June 2019. Based on the analysis, the visibility test developed based on the elongation of the moon (dependent variable) and altitude of the moon (independent variable) gives the smallest rate of misclassification. From the statistical analysis, we propose the elongation of 7.28°, the altitude of the moon of 3.39° and the arc of vision of 3.74° at sunset as the new crescent visibility criteria. The new criteria have a significant impact on improving the chance of observing the crescent moon and hence producing a more accurate Islamic calendar in Malaysia
Household indebtedness and non-performing loans in Malaysia / Theong May Jin
No full textAggregate non-performing loan (NPL) ratios in Malaysia have been decreasing steadily. However, there has been increasing awareness concerning predicting banking vulnerability and systemic risk in the financial market when debt grows faster than the economy. At the end of 2018, Malaysia’s household debt fell to 83% of the GDP ratio. In fact, in value, total household debt grew from RM1.08 trillion in 2016 to RM1.18 trillion in 2018. Besides, household borrowing has been increasing over recent years. It comprised about 57% of Malaysian banks' total lending, as of 2018, which has exposed the banks to ex-post credit risk. Aggregate NPLs have been considered the transmission channel of macroeconomic shocks to the banks' balance sheets. However, another strand of literature on analysing NPL by category has been less noticed by the researchers. At times of stress, these relationships may be nonlinear. For these reasons, first, the present study examined the relationship between four common household credit facilities and Malaysian household NPLs, controlled by a set of indicators. Narrowing down to household NPLs by economic purpose, this study examined the chosen sets of economic indicators that determine the former movements and their relative strength in their impact. The study also compared the appropriate approaches in capturing the dynamics (linear versus nonlinear) between the tested variables. Using an available monthly dataset of macroeconomic and monetary variables from January 2006 to December 2018, linear and nonlinear autoregressive distributed lags (ARDL) were employed. The findings showed that finance-constrained households were more likely to default on credit card loans than other types of loans during times of financial distress. Household NPLs and personal loan debt were found to be better explained in a linear specification, in a negative direction, assuming consumers tend to pay off other debt using easy to access loans at any time. There was no long-run relationship between them—properties outstanding loans and household default using the ARDL approach. However, NARDL revealed a possible relationship between loans and NPLs. Both positive and negative property loan changes were significant, whereas negative changes significantly impacted household NPLs. In another direction, the results showed that macroeconomic shocks affected consumer and mortgage loans differently; however, asymmetrical changes of the overnight policy rate (OPR) did not contribute to any type of NPLs. A hike or cutback in the OPR was a response toward the economic outlook and price changes; hence the effect of the OPR was muted, comparatively. In addition to the macroeconomic determinants, this study assessed how the loan portfolio affected each type of NPL. When other debts were factored in, credit card loan borrowers with another loan (s) tended to default on their credit card debt, compared to those without credit cards. Personal loan defaults were not linked to household debt, as personal loan borrowers usually covered their debts by taking up additional personal loans. Lastly, high housing loans and high vehicle loans contributed to the high default rate of residential properties and transport vehicles debts, respectively