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Interval estimation of the concentration parameter and missing value imputation in the von mises distribution / Nor Hafizah Moslim
No full textThis study focuses on the construction of confidence interval for parameters and analysis of
missing values for circular variables. The scope of the study is the von Mises distribution
where it is also known as circular normal distribution. It is worthwhile to note that statistical
theories for straight line and circle are different from one to another because the circle is a
closed curve but line is not. The study is on the construction of the confidence interval (CI)
for the concentration parameter of von Mises distribution. Here, the proposed methods is
CI based on calibration bootstrap and compared with the present methods to achieve the
best confidence interval for the concentration parameter. The present methods involve in
the study are CI based on percentile bootstrap, CI based on asymptotic distribution of ˆ _
and CI based on bootstrap-t. The coverage probability and expected length values from
each method are examined. The simulation study shows that CI based on the calibration
bootstrap is good in terms of coverage probability with reasonable expected length. Next,
the study is on the derivation of a new statistic based on circular distance for circular
data. From the simulation study, the new statistic is approximated to the chi-squared
distribution for large concentration parameter, _. Based on the new statistic, a CI for the
concentration parameter is constructed as well. Numerical results suggest the CI based
on 32nd percentile gives the most efficient performance. The final part of the study is
analysing the missing values for the circular variables. The simulated data are assigned to
six different percentages of missing values. Then, the missing data are imputed with two
methods; mean imputation and bootstrap-t. Three indicators namely mean, estimate bias
(EB) and estimate root mean square error (ERMSE) are used to measure the performance of concentration parameter for each method. Through the simulation study, we observe
that the bootstrap-t method performs better than the other method to impute missing values.
For illustration, real data consisting of data in angle form found in literature are used
Autism spectrum self-stimulatory behaviours classification using explainable temporal coherency deep networks and SVM classifier / Liang Shuaibing
No full textAutism spectrum disorder is a very common disorder. An early diagnosis of autism is essential for the prognosis of this disorder. The common method for diagnosis utilizes behavioural cues of autistic children. Doctors require years of clinical training to acquire the ability to capture these behavioural cues such as self–stimulatory behaviours. In recent years, the advancement of deep learning algorithms and hardware enabled the use of artificial intelligence technology to automatically capture self-stimulatory behaviours. Using this technique, the work efficacy of doctors can be improved. However, the field of self-stimulatory behaviours research still lacks large, annotated data to train the model. Therefore, the application of unsupervised machine learning methods is adopted. Meanwhile, it is often difficult to obtain good classification results using unlabelled data, further research to train a model that can obtain good classification results and at the same time being practical will be valuable. Nevertheless, in machine learning, the interpretability of the created model is also important. Hence, we have utilized the Layer-wise Relevance Propagation (LRP) method to explain the proposed model. In this work, the major innovation is utilizing the spatio-temporal continuity of close frames as a free form of supervision and setting a global discriminative margin to extract slow-changing discriminative self-stimulatory behaviours features. Extensive evaluation of the extracted features has proven the effectiveness of those features. Firstly, the extracted features are classified by the k-means method to demonstrate the classification of self-stimulatory behaviours in a completely unsupervised way. The conditional entropy method is used to evaluate the effectiveness of features. Secondly, we have obtained the state-of-the-art results by combining the unsupervised TCDN method with optimised supervised learning methods (such as SVM, k-NN, Linear Discriminant Analysis). These state-of-the-art results prove the effectiveness of the slow-changing discriminative self-stimulatory behaviours features
The design and evaluation of the M-Kids mobile application to engage learning among Islamic pre-schoolers in Malaysia / Wan Irma Sabrina Idris
No full textRecently, there has been renewed interest in the issue of providing a proper education for young children aligned with the development of the rapid technology era. This study aims at identifying the changes in cognitive and behavioural development in Islamic preschool children aged five to six years old in Malaysia upon the usage of the designed and well-developed M-Kids Mobile Learning Application prototype. Several studies have documented that technology is a forerunner in the future of learning (Keegan, J., 2016), and even in Malaysia's education system for instance, as reported by Chin (2018) in The Star Online, public schools in Malaysia are going digital with the introduction of e-textbooks starting in 2019 as announced by Deputy Education Minister. More recently, in line with helping children and youth affected by COVID-19, United Nations International Children's Emergency Fund (UNICEF) and Microsoft Corporation have announced the expansion of a global learning platform. This is before the available data from UNICEF where 1.57 billion students have been affected by school closures in more than 190 countries worldwide (Thompson, 2020). Due to this factor, a community such as parents, educators and researchers started to debate upon one question which has been concerned by the outcome of this scenario: are the technology-related practices developed appropriately for young children (Guerrero et al., 2019; Straker et al., 2018). Thus, this study, which is in response to the suggestion, set out to design and develop appropriate content in the mobile application for young children. A design-based research framework (Thomas C. Reeves., 2006) as a methodological approach was used, dividing this study into five phases with five objectives; finding the needs through needs analysis, design and evaluation of theories through thematic analysis, development of a prototype and iterative of solution through usability heuristic analysis, prototype implementation through observation and finally getting feedbacks from solutions through mobile heuristics analysis for children. 150 preschoolers from 4 Islamic Preschools in Klang Valley, Malaysia were involved in this study. The findings indicated that there were positive feedback and highly agreement from parents and teachers on the changes in preschool children’s cognitive and behavioural development towards the usage of M-Kids Mobile Learning Application in their learning. M-Kids Mobile Learning Application managed to improve the child's cognitive development by making the child understand the story, comprehend, and answer the questions given. Parents and teachers agreed that M-Kids Mobile Learning Application managed to implement moral and Islamic values in the learning content, and they approved that the usage of the application was able to practice good behaviour in the learning process. Hence, the study results represent a further step for practitioners towards developing more mobile learning content that is appropriate and beneficial to the development of young children in the future
Pendekatan pengurusan stres berdasarkan konsep al-Nafs: Kajian terhadap ayat-ayat al Qur’an terpilih / Siti Hasmah Muhamad Don
No full textStress needs to be managed properly, otherwise, it can have adverse effects on individual health and also behavioral problems. There have been various stress management approaches applied in the West and Islam. The West, for example, uses many psychological approaches in managing stress. From the Islamic point of view, the stress management approach is derived from the Qur’an and hadith instructions. This study focuses on the stress management approach according to Islam which is based on the concept of al-nafs as highlighted in the Qur’an. A review of the previous literature has shown that studies on the Qur’an have succeeded in forming the concept of al-nafs (psyche) which is an important element in human beings. From this concept, various approaches on stress management according to Islam were formed, which were highlighted by the earlier and contemporary scholars. However, it is found that the stress management approach that leads to the concept of al-nafs itself is still less discussed, especially in the context of textual studies of the relevant Qur’anic verses. Therefore, this research highlights the stress management approach based on the concept of al-nafs by focusing on the study of the selected Qur’anic verses. This study is based on a qualitative method that used document analysis and content analysis. Findings of the study indicated that al-nafs system of the humans greatly influences the formation of behavior, including stress-related behaviors. This study also found that there are no specific Qur’anic verses that directly mentions stress management approach instead of it provides general indication. Thus, textual study of the relevant Qur’anic verses related to the context of al-nafs is pertinent for the community to embrace a more holistic stress management approach
Kefahaman dan penglibatan pelajar dalam pusat rawatan alternatif: Kajian di Politeknik Port Dickson / Normarlina Mohamad Lutpi
No full textRawatan alternatif telah diiktiraf dalam Islam dan juga dalam proses penguatkuasaaan Akta PT&K 2016 secara berfasa oleh pihak Kementerian Kesihatan Malaysia. Namun begitu, terdapat beberapa perkara yang sering menjadi perhatian dalam kalangan orang awam terutamanya para pelajar yang berasa keliru akan amalan pengubatan Islam. Jadi, pelaksanaan kajian ini adalah bagi menjawab empat objektif seperti berikut : i) menjelaskan konsep perubatan Islam sebagai rawatan alternatif, ii) mengkaji faktor-faktor yang mempengaruhi penglibatan pelajar dalam rawatan alternatif, penglibatan pelajar sebagai pesakit dan pelajar rawatan alternatif Islam, iii) menganalisis tahap pemahaman pelajar terhadap rawatan alternatif Islam, dan iv) menganalisis pengaruh pengetahuan dan penglibatan pelajar terhadap rawatan alternatif Islam. Metodologi yang diguna pakai membabitkan kaedah kuantitatif dan kualitatif. Bagi kaedah kualittaif, kajian perpustakaan, pemerhatian dan temu bual telah digunakan bagi mengumpul data. Manakala bagi kaedah kuantitatif pula, soal selidik telah menjadi instrumen dalam kajian ini. Responden dalam kajian ini meliputi para pelajar di Politeknik Port Dickson daripada pelbagai bidang pengajian di pelbagai jabatan. Secara keseluruhannya hasil kajian telah mendapati faktor-faktor penglibatan pelajar terhadap rawatan alternatif berada di tahap yang baik. Pemahaman mereka terhadap hukum hakam dan kaedah perubatan Islam juga berada di tahap baik. Manakala terdapat hubungan pengetahuan dan penglibatan sebagai pelajar tetapi hubungan tersebut berada di tahap yang lemah. Kajian ini memberi impak kepada Jabatan Pendidikan Politeknik dan Kolej Komuniti yang memerlukan penambahbaikan kurikulum berkaitan akidah oleh Seksyen Pembangunan dan Penilaian Kurikulum (SPPK) dan keperluan kepada pemantauan yang lebih oleh pihak bertanggungjawab dalam mengekang penglibatan para pelajar terhadap bidang perubatan yang tidak patuh kepada syariah
Education and purification in Da'wah Sufi methods: A reference to the reform method Syeikh Ahmad Zarruq's: A case study (846 AH – 899 AH) / Abdalsalam Ibrahim Hamad Gadalla
No full textReforming individuals and societies depends greatly on the extent they are connected to Education and Purification. Therefore, this study aimed to examine, generally, the importance of Education and Purification and, in particular, its significance in the Sufi Dawah to highlight the main characteristics of Sufi Dawah methodology and rectify some contemporarily applied methodologies. The research also aimed to examine the fundamentals of Education and Purification methodology of in order to adopt it in strengthening Dawah methodologies with scholarly precepts that could uplift the Sufi Dawah methodology in particular, and the Dawah methodology in general. The study also included the main attributes of the Dawah methodology of Ahmad Zarruq which specified the characteristics of his Education and Purification methodology.
The Sufi school has contributed many theoretical and practical solutions in relation to Education and Purification. Nonetheless, Sufism has suffered many deviations when some Sufists didn’t follow the Education and Purification teachings of Sufi scholars. To address this, the researcher opted to choose an exemplary case of reformatory Dawah i.e., the case of Ahmad Zarruq. This was due to his conspicuous role in the reform and revival in relation to Sufi Dawah methodologies. To highlight the main characteristics of his methodology in Education and Purification, the researcher examined Ahmad Zarruq's writings and deduced from them his methodology of Education and Purification. The study contained the fundamentals of his Education and Purification methodology which was deduced from the Quran and Sunnah. This methodology is distinguished by its ability to address many issues realted to Education and Purification in the Sufi school.
the researcher adopted the deductive, critical, comparative and deductive method, methodology among the findings of which:
The researcher realized the great importance of Education and Purification in building individuals and societies. Also, Sheikh Ahmad Zarruq has established his methodology on firm precepts from the Quran and Sunnah. He rarely mentions an issue without supporting it with its evidence from the Quran or Sunnah. The Dawah methodology of Ahmad Zarruq is distinguished by its comprehensiveness as it establishes the foundation evidence from the Quran or Sunnah. The Dawah methodology of Ahmad Zarruq is distinguished by its comprehensiveness as it establishes the foundation
Sporopollenin supported imidazolium-based ionic liquids: Synthesis, adsorption studies, and application in mixed matrix membrane for phenol extraction / Kumuthini Chandrasekaram
No full textThe study explores the immobilization of imidazolium-based ionic liquids onto the surface of sporopollenin, a naturally occurring biopolymer, to form sporopollenin-imidazolium (Sp-IM) biosorbent and subsequent dispersion of Sp-IM onto cellulose triacetate (CTA) polymeric phase to contrive mixed matrix membrane (MMM). Sp-IM was prepared in variations of imidazolium cations including methyl, butyl, and decyl based alkyl chains as well as benzyl substituents. The successful immobilization of imidazolium onto sporopollenin was characterized with Fourier transform infra-red spectroscopy (FTIR), solid-state 13C nuclear magnetic resonance spectroscopy (NMR), field emission scanning electron microscopy (FESEM), energy dispersive X-Ray spectroscopy (EDX), Brunauer-Emmett-Teller (BET) analysis and thermogravimetric (TGA) analysis where notable presence corresponding to imidazolium and its substituents were detected. FESEM analysis recorded uniform surface coating with sporopollenin retaining its inherent structure. While BET analysis revealed definitive mesoporous characteristics with increased surface area 3.1-11.4 m2/g and pore size 5.1-62.7 nm. A series of aromatic-based compounds were then screened using Sp-IM as an adsorbent, where the mildly acidic 2,4-dinitrophenol (2,4-DNP) was discovered as the most responsive. The biosorption was deeply influenced by the ionization potential of 2,4-DNP and the strong π-π interaction between the imidazolium and phenol aromatic rings. Since neither the alkyl chain length nor the presence of benzyl substituent in imidazolium played a significant role, the adsorption of 2,4-DNP was optimized using sporopollenin-methylimidazolium (Sp-MIM) via UV-Visible spectroscopy. Adsorption study indicated that the biosorption of 2,4-DNP onto the surface of Sp-MIM adheres to Langmuir’s monolayer isotherm and the chemisorption kinetic pathway. Sp-MIM was then further developed as MMM particle-phase with CTA forming Sp-MIM-MMM. Sp-MIM-MMM was consequently applied for simultaneous dispersive membrane microextraction (DMME) of nitro- and chloro-substituted phenols from various matrixes followed by determination using high performance liquid chromatography with diode array detection (HPLC-DAD). Several main variables influencing the Sp-MIM-MMM based DMME efficiency were validated and optimized. Method validation recorded notable repeatability and reproducibility performance with observed linearity 50-500 ng/mL, the calculated linear regression (R2) was 0.9994-0.9997, relative standard deviation (RSD) was 0.2-0.8 %, the limit of detection (LOD) was 0.03-0.06 ng/mL, the limit of quantification (LOQ) was 0.11-0.19 ng/mL while the recovery was 99-119 % for all phenol analytes in ultrapure water. Targeted selectivity and sensitivity of the Sp-MIM-MMM towards the phenol analytes were evident in the various sample matrix tested with quantified detection calculated at 3.6-154.7 ng/mL for liquid-based-real samples (industrial water stream and honey) and 12.3-1477.9 μg/kg for solid based-real samples (detox drinks and weight-loss supplements). Sp-MIM-MMM exhibited notable stability and mechanical strength with uncompromised reusability potential up to 10 cycles of extraction. Whilst, the Sp-MIM particle phase recorded high resilience, stability, and durability, henceforth no leaching of ionic liquids was observed even after repeated use. Exceptionality, Sp-MIM also demonstrated additional strong regenerative prowess which inadvertently promotes continuous material recyclability potential. The study hence indicates that the adopted concept of Sp-MIM-MMM based DMME broaches new pathways in the development of environmentally sustainable material and technology
Self-healable functional polymer hydrogel electrolytes based energy storage devices for electronic applications / Maryam Hina
No full textThe development of functional hydrogel electrolytes possessing superb ionic conductivity, self-healing, and mechanical properties simultaneously is still a challenge for application in energy storage devices. To overcome this issue, we developed novel poly (acrylamide) hydrogel through free radical mechanism and sodium montmorillonite clay was used as a physical crosslinker. Lithium trifluoromethanesulfonate (LiTF) salt, lithium trifluoromethanesulfonate/poly (3,4-ethylenedioxythiophene): poly (styrene sulfonate) (PEDOT: PSS) (salt/conducting polymer), potassium hydroxide (KOH) base, and sulphuric acid (H2SO4) were added as ion sources in poly (acrylamide) hydrogels to prepare the hydrogel electrolytes. Numerous formulations of hydrogel electrolytes were developed by varying the amounts of salt, conducting polymer, base and acid to investigate the effect of ion sources on their properties and electrochemical characteristics. These poly (acrylamide) hydrogel electrolytes are poly (acrylamide)/ lithium trifluoromethanesulfonate (LiTF) (10 wt.%, 20 wt.%, 30 wt.%, and 40 wt.%≈AAM1, AAM2, AAM3, and AAM4), poly (acrylamide)/ lithium trifluoromethanesulfonate/ poly (3,4-ethylenedioxythiophene): poly (styrene sulfonate) (PEDOT: PSS) (30 wt.% LiTF≈AAM3 and 40 mg, 60 mg, and 80 mg PEDOT:PSS≈PEDOTAAM32, PEDOTAAM33, and PEDOTAAM34), poly (acrylamide)/ potassium hydroxide (KOH) (5M and 6M KOH≈AAMKOH (5M) and AAMKOH (6M)), and poly (acrylamide)/ sulphuric acid (H2SO4) (1M and 2M≈ AAMH2SO4 (1M) and AAMH2SO4 (2M)) respectively. The synthesized hydrogel electrolytes were characterized using numerous techniques. The deconvolution of Fourier transform infrared spectroscopy (FTIR) spectra of hydrogel electrolytes was obtained to investigate the transport numbers and to observe the synergy between the presence of functional groups/molecules/ions and ionic conductivity. The ionic conductivity was measured at both ambient and higher temperatures (298K - 373K) for all the hydrogel electrolytes. The highest ionic conductivity (σ) was achieved by AAM3, PEDOTAAM34, AAMKOH (6M), and AAMH2SO4 (2M) (9.34, 13.70, 9.51, and 18.10 ×10-3 S/cm) at ambient temperature, respectively. The transference number measurements clarify the charge carriers' transport in the hydrogel electrolytes. Furthermore, the supercapacitor cells were fabricated by sandwiching the hydrogel electrolytes between symmetric carbon-coated graphite electrodes and electrochemical studies were performed. The highest performing cells, AC/AAM3/AC, AC/PEDOTAAM34/AC, AC/AAMKOH (6M)/AC, and AC/AAMH2SO4 (2M)/AC attained maximum specific capacitance of 143.00 F/g, 327.00 F/g, 240.00 F/g, and 387.75 F/g at 3 mV/s, respectively and the specific capacitance, energy density, power density in galvanic charge-discharge studies of these high performing symmetric supercapacitors were 155.47 F/g, 385.40 F/g, 213.85 F/g, and 405.81 F/g and an energy density of 21.48 W h/kg, 53.57 W h/kg, 29.49 W h/kg, and 56.18 W h/kg at power density of 99.78 W/kg, 100.008, 498.40 W/kg, and 499.40 W/kg, respectively, as demonstrated by cyclic voltammetry and galvanic charge-discharge studies. The real time supercapacitor devices developed by connecting the two symmetric cells in series were charged and then discharged by illuminating the light-emitting diode (LED). In addition, the self-healable characteristics of hydrogel electrolyte and symmetric supercapacitors were confirmed by powering up a light-emitting diode (LED) and cyclic voltammetry study. Moreover, the cyclic stability of the fabricated devices was conducted before and after self-healing for 5000 cycles. From the obtained results, it can be understood that all the hydrogel electrolytes and fabricated supercapacitors produced excellent results. This work ventures the frontiers of hydrogel electrolytes and flexible energy storage devices as a booming invention for smart electronic devices
Characterization of the reactive oxygen species and reactive nitrogen species defense system in berangan banana / Fung Shi Ming
No full textMusa spp. cv. Berangan banana (AAA) is one of the most susceptible cultivars to Panama disease which is caused by the hemibiotrophic soil-borne pathogen Fusarium oxysporum f. sp. cubense (FOC). Panama disease, also known as Fusarium wilt causes great losses to global banana production. It is crucial to study the defense mechanism of banana plants against this disease in order to facilitate future solutions for this devastating disease. In this study, two-month-old Berangan banana plants were infected by soaking the roots in Fusarium oxysporum f. sp. cubense (FOC) culture. The plants were harvested at intervals of 1, 2, 4, 6, 8 and 10 days following infection. The fungus infects the plants from the zone of differentiation in the roots or any existing wounds. Penetration of FOC into the root causes cell disintegration leading to ions reflux in plant cells and resulting higher lipid peroxidation. In this study, cellular damage was observed in infected roots, rhizomes and pseudostems through Field Emission Scanning Electron Microscope (FESEM). Hyphae and conidia of FOC as well as tylose formation in the vascular bundle were visible. Increased levels of reactive oxygen species (ROS) such as superoxide anions (O2˙ˉ), hydrogen peroxide (H2O2), hydroxyl radicals (•OH) was one of the earliest responses observed in infected samples. Enzymes responsible for ROS synthesis, NADPH oxidase, were also up-regulated, which explains the oxidative burst at the pathogen attacking site, roots, and other parts of the plants, pseudostems and leaves at later stages of infection. ROS scavenging enzymes, superoxide dismutase (SOD), catalase (CAT), glutathione S-transferase (GST), peroxidase (POD), ascorbate peroxidase (APX), and glutathione reductase (GR) play an essential role in monitoring the ROS level. A sharp increase in the ROS level and enzymatic activities were observed in the infected plants. The increment of ROS was biphasic whereas the ROS scavenging enzyme activities increased initially and decreased at later stages. Secondary metabolites such as phenolic compounds were also reported to be able to scavenge the harmful radicals in order to protect the host plants from fungal invasion. Methanol extract of the FOC infected Berangan banana plant roots, pseudostems and leaves were assessed for DPPH radicals scavenging activity, reducing power assay, total antioxidant activities, total flavonoid content and total polyphenol content. Results indicated that the amount of total phenolic and flavonoid compounds as well as antioxidant activity were higher in infected plants compared to healthy plants. However, the phenolic compound decreased at the later stage of infection. Subsequently, the phenolic and flavonoid profiles were analysed using liquid chromatography – mass spectroscopy (LCMS). Metabolites such as quinic acid, ferulic acid, caffeoyl glucose, p-coumaric acid, caffeic acid, p-hydroxybenzoic, kaempferol-rhamnose-hexose, quercetin, catechin, and rutin were identified with different concentration in different parts of the plants at different intervals
Natural sensitizers for solar cell based on gel polymer electrolytes containing iodide/triiodide redox couple / Marziyeh Alinejad
No full textPolyvinyl alcohol (PVA) based gel polymer electrolytes (GPEs) containing iodide/triiodide have been prepared. Two types of solvents namely dimethylformamide (DMF) and dimethyl sulfoxide (DMSO) have been used in the preparation of the GPEs. The GPEs are (i) DMF/PVA/KI/I2, (ii) DMF/PVA/KI/I2/4-tert-butylpyridine (TBP), (iii) DMSO/PVA/KI/I2 and, (iv) DMSO/PVA/KI/I2/TBP. The ionic conductivity of GPEs at different temperatures have been determined from the electrochemical impedance spectroscopy (EIS) measurement. X-ray diffraction (XRD) and Fourier-transform infrared spectroscopy (FTIR) have been performed to analyze the structural properties of the GPEs. All GPEs have been tested for dye-sensitized solar cell (DSSC) with natural sensitizers extracted from different natural sources namely blackberry, blueberry, raspberry and saffron. DSSCs have been characterized with J-V measurement, EIS, Intensity modulated photocurrent spectroscopy (IMPS), and Intensity modulated photovoltage spectroscopy (IMVS). The GPEs without TBP shows the ionic conductivity of (14.05±3.50) mS cm-1 for DMF GPE and (2.45±1.51) mS cm-1 for DMSO GPE. The addition of TBP does not improve the ionic conductivity of the GPE with (11.99±6.84) mS cm-1 for DMF GPE and (2.98±1.35) mS cm-1 for DMSO GPE. DSSCs have been fabricated by sandwiching GPE in between photoanode and platinum counter electrode. The photoanode has been prepared by coating two layers of TiO2 on fluorine doped tin oxide (FTO) substrate via doctor blade method and sensitized with natural sensitizer. DMF/PVA/KI/I2/TBP GPE exhibit the best performance in DSSC with anthocyanin dye system. The best performance of DSSC can be explained via the charges transfer resistance, electron transfer time and electron recombination time from the EIS, IMPS and IMVS data respectively