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Production of sustainable methanol from plastic wastes by green energy to optimize landfill area / Dineshini Ganeshmoorthy
No full textThe fundamental element required to produce methanol is syngas. Many researchers have carried out in depth experiment on using plastic wastes to draw syngas which can be turned into methanol. Howbeit, the process of making this alternate fuel should be taken into consideration in order to attain sustainability. Exploiting the plastic wastes into a pyrolysis system that converts into methanol could reduce the expansion of landfill problem while contributing to alternate fuel. However this does not make the whole system sustainable unless the electricity required to operate is drawn from renewable source. In this paper, a thorough study showed on the possibilities of making the methanol production sustainable by substituting the raw material into plastic. Besides, the obsolete concept of energy storage system will be presented explaining how it could contribute to sustainable methanol production. On the other hand, based on the data collected from other research papers, the total amount of methanol that can be produced from the plastic wastes generated daily will be calculated. The propagation of plastic weightage to produce 1 litter of methanol was attained from an experiment conducted at a R & D chemical located at Kajang. From this calculation, a presumption were showed on the geographical layout that about 1/3 of the landfill area were saved. There are innumerable landfills been operating in Malaysia. Thus to explain the land reduction at landfill, Pulau Burung Landfill, Penang will be taken as an example to demonstrate by inserting the boundary coordinates of the overall location along with reduced landfill area location using polygon features in the GQIS software. The overall land and optimized land will be exemplified from the geographical image obtained from QGIS software. Considering this approach will be elucidated on how it greatly affect the Malaysia’s economic and environment
Covid-19 management strategies for higher learning institute: A case study in Universiti Malaya / Hazren Mohd
No full textCOVID-19 affected nearly every country and more than 50 million individuals
worldwide. Many businesses and services were unprepared for the effects of COVID-19
on their daily operations. Also affected by the COVID-19 pandemic are Higher Learning
Institutions (HLIs). Pandemic management in HLIs requires the deployment of methods
based on health, economic, legal, and humanistic considerations. Therefore, in this work,
a comprehensive COVID-19 management guideline was developed by taking into
consideration the overall operation and activities of the HLI campus. The COVID-19
management guidelines consist of a checklist that covers key aspects and strategies for
managing COVID-19 or any other pandemic in HLI in the future. The strategies evaluated
the requirements of many stakeholders, including financial and legal considerations.
Subsequently, the COVID-19 management guidelines also consisted of detailed
procedures from designing and implementing strategies to monitoring and reporting on
incidents of the pandemic. The practicality of using the COVID-19 management
guideline was validated at the University of Malaya. The result showed that the COVID-19 management guideline is practical as a reference to implementing pandemic
management strategies with minimum resource requirements. Hence, the study has
demonstrated that the COVID-19 management guidelines established can be used to
initiate pandemic management strategies in HLIs
Computational harmonic analysis on plate-like base panel of air conditioning outdoor unit using direct method / Choon Wei Feng
No full textHarmonic response analysis is a useful tool to check for the structural response
(acceleration) when subjected to constant harmonic excitation. By extracting the response
of the desired spectrum from the structure by using finite element method, the potential
resonance or peaks with high vibration can be observed. In HVAC industries, the source
of vibration are from unit transportation, fan motor vibration and compressor vibration,
engineers will have to design and test the components of the unit to ensure the component
can withstand the vibration. This study focusses on the effect of transportation vibration
against the base panel of an air-conditioning outdoor unit. To ensure all component can
withstand road and ship transportation vibration, Daikin utilizes hydraulic shaker with a
prefix harmonic vibration profile to represent actual transportation condition. FEA can be
used during design stage of component to check the vibration integrity. Commercial FEA
solver is usually expensive, with its licensing cost. The alternatives would be using open�source FEA solver such as Code_Aster®. Usage on Code_Aster® will lead to extensive
saving in licensing cost. To ensure the method of an open-source solver is valid,
simulation results from Code_Aster® will be compared against commercial solver (Altair
Optistruct®) currently use in Daikin. Modal and harmonic response analysis will be
constructed on both solvers, with similar boundary condition and properties and proper
keyword. To further enhance the validity, two experiment will be done to verify the results
from the simulations. EMA are used to check the modal parameters such as natural
frequency and mode shapes of the base panel against the result from FEA. Shaker with
harmonic excitation from 5Hz-100Hz will be used to excite the base panel,
accelerometers will be used to collect the response such as acceleration from different
location. Response from simulation and experiment can be use as comparison and verification. After the validation process through experiment, Code_Aster® modeling
technique can be integrated into design workflow of DRDM with confidence. When
comparing Code_Aster® with Altair Optistruct®, the frequency difference are only
within 1.89% and the MAC plot in all 8 modes are near to 1. This shows that the settings
used are correct in Code_Aster®. The results validation for normal mode in Code_Aster®
with EMAshows that mode 1, 2, 3, 5 and 7 are present and comparable, mode 4 and mode
6 are missing from EMA. This might be due to localized mode which is not captured by
accelerometer. The maximum error on frequency against EMA is only 12.6%. Experiment
harmonic response analysis can capture the peaks of resonance and the shapes are
comparable to FEA although the magnitude in FEA is higher. Improvement can be made
in FEA by using element with actual material data in weld and screw area to reduceoverall
stiffness. More accelerometers can be used to measure the response on the panel to capture
localized mode in multiple DOF, actual damping coefficient from EMA can beinputted
into FEA to generate an accurate response
An efficient channel coding and short preamble design for mission critical machine-type communication over wireless networks / Najib Ahmed Mohammed Ahmed
No full textMachine-type Communication (MTC) plays an imperative role in wireless networks
and becomes the dominant communication paradigm for various real-time applications
including industrial automation, public safety, healthcare, utilities, transportation, smart
cities, and numerous other applications. Hence, wireless system is expected to a larger
extent, will be used in the context of MTC. Mission-critical MTC (mcMTC), also referred
to as Ultra-reliable Low-latency Communication (URLLC), has become a research hotspot.
It is primarily characterized by communication that provides ultra-high reliability and very
low latency to concurrently transmit short commands to a massive number of connected
devices. However, mcMTC poses significant transmission challenges over wireless
channels, as it is prone to channel noise, interference, distortion, and bit synchronization
errors. In addition, supporting small data communications for concurrent connection for
a massive number of MTC devices and providing insights in trade-offs between latency
and reliability have been neglected. The mcMTC has a significant technical impact on the
design of all layers of the communication protocol stack. While the reduction of PHY layer
overhead and improvement in channel coding techniques are pivotal in reducing latency
and improving reliability, the current wireless standards dedicated to support mcMTC
rely heavily on adopting the bottom layers of general-purpose wireless standards and
customizing only the upper layers. As such, the PHY layer design requires further analysis
to realize the stringent requirements of mcMTC. In this study, an innovative architecture is proposed for mcMTC applications through PHY layer named Mission Critical WiFi
(MC-WiFi) targeted at reducing the end-to-end (E2E) latency by minimizing the packet
transmission time and improving the reliability by proposing a one preamble symbol Packet
Detection and Channel Synchronization (PDCS) algorithm and implementing of polar
codes in the wireless channel. Mathematical results show that the proposed architecture
allows a substantial reduction in packet transmission time, down to 5 μs and guaranties
error probability at
Systematic selection of blockchain platforms using Fuzzy AHP-TOPSIS / Shahr Banoo Muradi
No full textVarious businesses and industries such as financial, medical care management, supply chain management, systematic instruction, data management, fundraising platforms, Internet of Things (IoT) and government supremacy, have been using blockchain technology to develop systems. Similar to other technologies, despite the superiority it holds, some shortcomings and issues accompany the adoption of Blockchain. interoperability challenges, security attacks, sustainability, latency, availability issues related to blockchain performance and scalability are listed as the most critical challenges standing against its vast adoption. If the blockchain platform is not properly selected, the functionality and quality of the blockchain-based systems could be biased. Furthermore, choosing the right platform that best meets the project requirements and targets is getting complicated due to the availability of numerous blockchain platforms with unique properties and specifications. For this, the design of a systematic selection method that contributes decision-makers toward a suitable blockchain platform choice is highly desirable. During the selection of blockchain platforms, many criteria need to be taken into account depending on the organization, project and use case requirements. If the selection criteria are derived carefully concerning the specified factors, the effectiveness and feasibility of the selection method will be enhanced. This research proposes a set of selection criteria that cover both features and quality attributes of the blockchain platforms. A systematic selection method is proposed based on the Fuzzy AHP-TOPSIS approach which compares and select alternative blockchain platforms against the selection criteria. Three industrial cases were used to prove the accuracy of the ranked list of alternatives generated by the proposed selection method. Additionally, an evaluation by blockchain experts was performed and the results show that the proposed selection method can be applied practically to support the decision-makers in blockchain platform selection for real-world projects
Enhancing system performance using persistent ram modules as storage class memory / Tebra A Moussa Jummah
No full textThroughput and time latency are critical performance metrics of most application systems; thus, any underlying storage technology must provide the best of both metrics. Since hard disk drive (HDD) and solid-state drive (SSD) became an I/O bottleneck performance for most intensive data applications, a new storage technology must be produced to address this issue. Storage class memory (SCM) emerged as the new promising technology with byte-addressable, high access time, and persistent features. In this research, an SCM emulator was implemented using a kernel module based on a RAM named ZRAM, which served as a general-purpose RAMDISK feature with persistence. Further, a test has been conducted on the implemented emulator with persistent RAMDISK and PMEM. The experiments conducted in this research were done through three stages: the first of which involved testing the workload within different data placement devices; the second stage involved running of tests upon a collection of disk filesystems, RAM filesystem, and persistent memory filesystem (PMFS). At the third stage, experiments were conducted to examine the effect of moving data files on performance. The implemented emulator persistent ZRAM (PZRAM) achieved superior performance as compared to HDD and SSD with a performance improvement of 14290% and 1167% respectively, a slide higher performance than PMEM with 2.3% improvement and almost similar performance of persistent RAMDISK. Additionally, the proposed PZRAM with TMPFS running on top of it has provided better performance with 11.83% over PZRAM with ext4. Further, this research provided comparative experiments on the effect of filesystem and moving data files on throughput and latency performance
The role of Adab al-Sultaniyyah in Fiqh al-Siyasah Alsyar`Iyyah: A comparative study between the works of al-Adab Alsultaniyyah and al-Ahkam al-Sultaniyyah / Ayidh Awwadh A Alharthi
No full textNothing of the Islamic thought remained except for two schools of jurisprudence (fiqh): Jurisprudence of Islamic Politics and the school of advice represented by the Islamic governance etiquettes. This study discussed the impact of the Islamic governance etiquette on jurisprudence of Islamic Politics. This study emanated from a basic supposition that reflects the governance etiquette being influenced by many various cultures that constitute it, particularly when the non-Islamic background influence on the governance etiquettes is transferred to the jurisprudence of Islamic politics. The importance of this study lies in the trial to separate the governance etiquettes from the jurisprudence of Islamic politics after the confusion overwhelmed many of the current researchers.The research aims at comparing the Islamic governance etiquettes to the jurisprudence of Islamic politics in terms of kinds of those who write about both of them, and their main topics and the renovation that attached to both, so that the researcher can identify the impact of the books of governance etiquettes on the jurisprudence of Islamic politics. The researcher adopted the analytical methodology and comparative methodology to achieve the study objectives.The dissertation concluded some results, the most important of which are what follows. The jurisprudence of Islamic politics is an independent knowledge and an integral part of the Islamic jurisprudence concerned on the state in Islam and the legislation of its regulations,in order that it realizes the public interest and does not contradict the rules and principles of the Islamic legislation. Second, the authors who write about the jurisprudence of Islamic politicsare from different careers and cultures. Writing about governance etiquettes continues because it does not require special capabilities or specifications. The influence of the governance etiquettes on the jurisprudence of Islamic politics was noticeable in the centrality of ruler and its call for political class, while it was not affected by the absence of a political theory representing it nor its call for unconditional obedience
Analisis produk Ar-rahn di institusi kewangan Islam di Malaysia menurut perspektif fiqh / Siti Hazirah Che Harun
No full textAr-rahn “merupakan antara kontrak yang digunapakai dalam produk pembiayaan Islam bagi membantu individu dan Perusahaan Kecil dan Sederhana” (PKS) “memperolehi wang dengan segera dan mudah.“Para fuqaha’ telah bersepakat bahawa hukum kontrak pajak gadai (ar-rahn) adalah diharuskan berdasarkan dalil-dalil al-Quran dan Sunnah..” Bertitik “tolak daripada dalil keharusan yang berbentuk umum,”maka “struktur kontrak ar-rahn di Malaysia adalah berbentuk hibrid di mana terdapat gabungan beberapa kontrak Islam yang lain dalam satu produk pembiayaan iaitu al-qard al-hasan (pinjaman tanpa faedah),” ar-rahn (cagaran), “al-wadi’ah (simpanan) dan al-ujrah (upah simpan) seperti yang diamalkan oleh Institusi Kewangan Islam Malaysia.”“Namun begitu, pada tahun 2019 Majlis Penasihat Syariah Bank Negara (BNM) memutuskan bahawa produk pembiayaan ar-rahn yang diamalkan oleh perbankan Islam Malaysia adalah tidak memenuhi keperluan Syariah yang ditetapkan.”Keputusan ini telah memberi implikasi besar terhadap operasi perbankan Islam di Malaysia yang menawarkan produk ar-rahn.” “Sehubungan itu, kajian ini meneliti isu-isu Syariah yang berbangkit daripada produk pembiayaan ar-rahn yang ditawarkan sebelum Februari 2020 dan produk pembiayaan ar-rahn yang telah dikemaskini. “Seterusnya isu-isu tersebut akan dianalisis dari perspektif fiqh.”“Bagi mencapai tujuan tersebut, kajian berbentuk kualitatif dipilih dengan” menggunakan dua pendekatan kajian yang berlandaskan kajian kepustakaan dan kajian lapangan. Kajian kepustakaan mengguna pakai metode dokumentasi dengan merujuk kepada perbincangan ar-rahn dalam kalangan fuqaha’ klasik dan kontemporari di samping lembaran pendedahan produk serta polisi dokumen ar-rahn BNM. Manakala kajian lapangan mengaplikasi metode temubual yang melibatkan informan dalam kalangan pakar muamalat dan eksekutif Syariah di perbankan Islam terpilih. “Seterusnya, data yang diperolehi akan dianalisis melalui analisis kandungan” dan tematik. Hasil kajian mendapati isu Syariah berkaitan ar-rahn adalah berbeza berdasarkan produk yang ditawarkan sebelum tahun 2020 dan yang dikemaskini bermula Februari tahun 2020. Isu Syariah sebelum tahun 2020 yang ditimbulkan BNM adalah “isu keterikatan setiap kontrak dan isu penggabungan kontrak.” Namun begitu, pengkaji mendapati “terdapat isu Syariah lain iaitu isu caj upah simpan lebih dari kos sebenar dan isu memanfaatkan marhun yang timbul daripada produk pembiayaan ar-rahn sedia ada.” Manakala, isu syariah dalam produk ar-rahn yang dikemaskini pada tahun 2020 dapat dilihat dalam kontrak tawarruq di mana produk ar-rahn semasa menggua pakai kontrak tawarruq yang melibatkan “isu berkaitan dengan komoditi, isu berkenaan ketiadaan penyerahan dan pegangan, isu berkaitan” pengaturan awal, wakalah dan isu yang boleh membawa kepada bay‘inah. Namun begitu pihak bank mempunyai mekanisme yang cukup bagus untuk mengurangkan kekerapan berlakunya isu-isu tersebut. Walau bagaimanapun, terdapat juga kemungkinan berlaku isu-isu teknikal yang tidak dapat dielakkan akibat sistem yang tidak berfungsi dengan baik dan kecuaian pihak bank dalam mengandalikan akad ar-rahn mahupun tawarruq
Photovoltaic fault detection and diagnosis based on adaptive-sampling rate and operating voltage approaches / Ahmad Rivai
No full textOver the last few decades, the photovoltaic power generation system (PV system) has gotten a lot of attention since sunlight as its source is clean, sustainable, and abundant. PV system also has lower maintenance and operational costs than other types of power generation systems. On the other hand, it suffers from high degradation rates because of the long-term operation, which is around 0.5 percent per year. Moreover, the PV system is commonly used in outdoor environments which makes it exposed to all kinds of weather, it is susceptible to a variety of faults. The PV system’s faulty drastically reduces power generation, accelerates system aging, and potentially ruins the entire system’s availability. As a result, PV systems fault detection and diagnosis (FDD) are essential to improve safety, reliability, and efficiency.
This thesis presents photovoltaic (PV) FDD based on the adaptive sampling rate and operating voltage approaches. They are offline and online PV FDD methods, respectively. The adaptive-sampling rate method is the offline approach employed for a multi-channel PV I-V curve tracer. The real-time operating voltage method is the online approach for PV string failure analysis. The I-V curve tracer’s performance has been improved using the adaptive-sampling-rate method, especially on data resolution and acquisition speed. Furthermore, more measurement points and a larger range of voltage and current can be measured using the proposed offline method. Quickly comparing and identifying faults in one or more PV modules is critical. A multi-channel PV I-V curve tracer prototype has been developed and used with an Arduino microcontroller and 30 PV modules for conducting the experimental tests. The I-V curve tracer’s performance and functionality have been confirmed by simulation and experiment. The I-V curve tracer prototype can quickly produce a smooth I-V curve within 57 ms with up to 256 measurements.
The PV module FDD which is based on the operating voltage approach is a simple and effective method that is realized by monitoring the real-time operating voltage of each PV module. All PV modules’ operating voltages are monitored using a self-powered wireless sensor network (WSN). A grid-connected PV system is used to test the proposed method. Each PV module is monitored for detecting faulty modules. The impact of various electrical fault scenarios on PV string characteristics is presented in the PV string failure analysis. As compared to the standard module, the results show that the faulty or degraded module has a lower operating voltage. A graphical user interface (GUI) application software that manipulates colours to graphically displays each module's real-time operating voltage has been designed to allow users to identify faulty modules quickly. The PV module electroluminescence (EL) imaging system further validates the faulty module identification method by clearly illustrating individual cell conditions.
Both offline and online methods have successfully eliminated the fault location investigation by the operators and shortened the fault problem-solving time. The offline and online methods reduced one-quarter and two-fifths of steps, respectively, from the conventional failure-solving process
Synthesis and spectroscopic characterization of functionalized indolenine derivatives / Abdul Qaiyum Ramle
No full textThis thesis focuses on the functionalization of substituted diformyl indolenines and
their spectroscopic properties. The experimental works for the synthesis of four new
series of indolenine derivatives are presented. The first series describes the reaction of
diformyl indolenines with phenyl hydrazines to produce pyrazoles as the sole product.
Treatment of pyrazole containing carboxylic acid with various substituted amino groups
resulted in the formation of amide pyrazoles. The supramolecular packing of these
pyrazoles was established by single X-ray crystallographic analysis. The second series
reports the preparation of indoleninyl-barbiturate zwitterions. The unusual separation of
charge between the iminium and enolate centers was elucidated by single X-ray
crystallographic analysis. The presence of amino and carbonyl groups allows the
zwitterions to be consolidated into a one-dimensional supramolecular layer via
intermolecular hydrogen-bonding interactions. Notably, the absorption spectra showed a
blue-shift with increasing solvent polarity. The presence of a small amount of TFA
resulted in the protonation of the enolate center. The third series outlines the synthesis of
indoleninyl-pyrimido[1,2-b]indazoles. The reaction was well-tolerated with a wide range
of substituents on the indazole and indolenine rings. The optical properties of indoleninylpyrimido[
1,2-b]indazoles were investigated. The final series of indolenines was formed
by reacting diformyl indolenines with 4,5-bis(octyloxy)-1,2-diaminobenzene to generate
dibenzotetraaza[14]annulenes (DBTAAs). The spectroscopic and computational analyses
of these macrocycles were discussed in detail