13474 research outputs found
Sort by
Effectiveness of using scratch® in enhancing word problem solving achievement in basic arithmetic among year two pupils / Usha Thangamani
No full textTeaching and learning of primary and secondary Mathematics in Malaysia wields problem solving as the central theme and fundamental emphasis in the curriculum content. However, problem solving which allows pupils to think critically, analytically and logically often viewed as complex mathematics area since it obliges knowledge of number sense and basic arithmetic operations and language skill. The purpose of this study is to determine the effect of using Scratch in enhancing word problem solving achievement in basic arithmetic among year two pupils. A total of 60 year two mixed ability pupils from a government primary school in Bangsar district were chosen as respondent of this quasi experimental study by convenience sampling. The experimental group (N=30) was subjected to lessons designed with Scratch while the control group (N=30) was subjected to lessons using the traditional method without Scratch. To answer the research questions, this study implemented a quantitative data collection method namely pre-test and post-test. Pupils’ achievement in solving word problems in basic arithmetic is analysed inferentially. Significant difference between pre-test and post-test of the experimental group year two pupils’ achievement in solving word problems in basic arithmetic is measured using paired samples t-test while significant difference in year two pupils’ achievement in solving word problems in basic arithmetic in post-test between the experimental and control group before and after the intervention is measured using independent samples t-test. Results of the paired samples t-test (M = -30.80, SD = 9.77), t (29) = -17.27, p < .001 revealed that there is a significant increase in the achievement of experimental group in solving word problems in basic arithmetic. Moreover, results of independent sample t-test (M =27.092), t (59) = 6.32, p < .05 indicated that there is a significant difference in posttest between the experimental and control group. These findings point out that the use of Scratch enhanced the pupils’ achievement in solving word problems in basic arithmetic
Penguasaan kemahiran manipulatif sains murid menengah rendah / Nor Amirah Mohamad Nor
No full textManipulative skills are psychomotor skills that enable students to use and handle science apparatus and substances correctly, handle specimens correctly and carefully, and sketch specimens accurately during scientific investigation. The inability of students to acquire science manipulative skills can affect the acquisition of other skills and scientific knowledge. Therefore, this study aims to investigate the mastery of science manipulative skills of lower secondary students. This is a qualitative study that was conducted over 7 weeks. Participants in this study were selected through purposive sampling technique that involved 10 Form 2 students and two science teachers. The researcher used experimental tasks to understand students' abilities in handling three basic apparatus namely; measuring cylinder, Bunsen burner and microscope. Data were obtained from observations while students performed experimental tasks using video recordings, interviews with students and teachers, and students’ work; that is their scientific drawings. The data obtained from the audio and video recording were transcribed and analyzed qualitatively. Data obtained through scientific drawing were analyzed using the criteria from Framework for Analyzing Students’ Scientific Drawing. The findings show that there is a pattern of students' mastery of manipulative skills in handling each of the apparatus. Mastery of the manipulative skills of most of the students were low where they were unable to identify the correct use of the apparatus. Main factors identified that influenced the students’ acquisition of manipulative skills were students’ prior knowledge and interest; teachers’ laboratory management and teaching method; apparatus complexity and quantity; and time. Implications and recommendations for future study were also discussed
The impact of positive psychological resources on career success among academic staff in Sudan / Mohammed Mustafa Mohammed Yousif Fadul
Get PDFCareer success is important in shaping individual vocation’s identity. Different individual will have various perceptions about their career accomplishment; whether they feel successful or otherwise. This research aims to investigate the impact of positive psychological resources on career success among academic staff in public universities in Sudan. This due to the importance of career success in contributing to both individual’s performance and organisational growth. The research is guided by protean career theory (PCT), conservation of resource theory (COR), and self-determination theory (SDT) for explaining the theoretical framework. On the other hand, the conceptual framework informed by protean career orientation (PCO) as an independent variable, career adaptability (CAA) and psychological capital (PsyCap) as mediator variables,
academics’ career success as the dependent variable, and Islamic work ethics (IWE) as a moderator. Data were collected from 398 academic staffs who work in public universities in Sudan using a drop-off and pick-up survey method. Data were analysed by using Smart-PLS and PROCESS macro software. The results revealed that PCO, CAA, and PsyCap were significantly related to academics’ career success. Additionally, the results emphasised that CAA and PsyCap mediate the relationships between PCO and academics’ career success. However, the moderated-mediation of IWE is not found in through the career adaptability path. This research provides implications both theoretically and practically including to the leaders in the universities to recognise PCO and psychological resources as important attributes to increase the level of academics’ motivation, and strength in order to determine their career success. Finally, the limitations of this research are discussed, and the directions for future research are suggested
Organic materials as saturable absorber for pulse generation at telecommunication window / Sameer Salam M.H. Mohammed Hussein
Get PDFThis thesis demonstrates several types of fiber lasers based on newly developed organic materials as saturable absorbers (SAs). We used these SAs in all-fiber based erbium-doped fiber laser (EDFL) ring cavity to produce Q-switched and mode-locked pulses at telecommunication window, at ~ 1560 nm. Three different organic materials were used in this thesis: Bis[2-(4,6-difluorophenyl)pyridinato-C2 ,N](picolinato)iridium(III) (FIrpic), bis(8-hydroxyquinoline)zinc (Znq2) and Tris(8-hydroxyquinoline)aluminum (Alq3). Finding new materials is still one of the defining characteristics of nonlinear optics field, as the rapid development of SAs has provided several new opportunities for nonlinear optics. Throughout this work, organic material showed a very interesting performance in terms of pulse duration, pulse energy, damage threshold, stability, spectral tunability, nonlinear response and proved to have a great potential in fiber laser technology. Organic materials are bio-compatible, environment-friendly, light-weight and mechanically flexible. The SA thin-films based on FIrpic, Znq2 and Alq3 in conjunction with polyvinyl alcohol (PVA) were successfully fabricated, in a simple, straight and low-cost process. A small piece of fabricated SA thin-film was inserted between two ferrules to form SA device. A set of measurements were taken to characterize the fabricated SAs, such as Fourier transform infrared (FTIR) spectrometer, optical absorption, linear and non-linear transmission. Different kinds of Q-switched fiber lasers with very high stability were successfully demonstrated using these materials. At first, FIrpic was used to develop a Q-switched laser with single- and dual-wavelength operation. Then, Znq2 was used to demonstrate Qswitching pulsing with fixed and tunable wavelength operation. The produced pulse width was decreased from 6.6 µs to 2.8 µs, while the repetition rate was increased from 45 kHz to 85 kHz. Finally, Alq3 was used as a Q-switcher to produce pulses at 1.5 µm and 1.0 µm regions. At 1.5 µm region, the pulse width and repetition rate were tunable within 1.2 µs to 6.65 µs and 31.65 kHz to 144.5 kHz, respectively. At 1 µm region, Alq3 produced high pulse energy and high peak power of 0.8 μJ and 237.62 mW, respectively, in two different setups. Stable ultrafast soliton laser operations were also achieved by using the developed SAs. At first, FIrpic was used to demonstrate a mode-locked laser with pulse width and repetition rate of 120 ns and 3.43 MHz, respectively. Similarly, Znq2 was also successful as a mode-locker, where it was used to produce a laser with a pulse width of 1.46 ps and a repetition rate of 3.5 MHz. Finally, a pulse width of 820 fs and a repetition rate of 4.9 MHz was achieved by using Alq3. Alq3 produced mode-locking operation with single and multi-wavelength operation at 1.0 µm with pulse width and repetition rate of 5.96 ps and 6.84 MHz, respectively. In conclusion, this work has successfully drawn attention to the potentials that organic materials have in fiber laser technology especially for Q-switching and mode-locking applications
Microstructural characteristics and mechanical properties of Sn-Ag-Cu solders with minor additions of Al and Zn / Leong Yee Mei
Get PDFDriven by the recent trend towards miniaturization of lead free electronic products, researchers are putting immense efforts to improve the properties and reliability of Sn based solders. Recently, much interest has been shown on low silver (Ag) content solder SAC 105 (Sn-1.0Ag-0.5Cu) solder because of economic reasons and improvement of impact resistance as compared to SAC387(Sn-3.8Ag-0.7Ag). The present work investigates the effect of minor (0.1-0.5wt.%) Aluminium (Al) and Zinc (Zn) addition to SAC105 on the bulk and interfacial structure between solder and copper substrate during reflow and after thermal aging , the mechanical properties of the solder joint and the nano-mechanical properties of IMC formed. Al and Zn have been chosen as they have shown promising results in improving the solder microstructure and mechanical properties from the previous studies. DSC was used to determine the effect of melting characteristics of SAC105 with addition of minor Al or Zn solder. XRD, FESEM, EPMA were used to evaluate the IMC phases and concentration of minor alloying element prior to the shear test and nanoindentation test. Nanoindentation was used to evaluate the mechanical properties of bulk and IMC formed in the solder. Minor addition of Al up to 0.5% promoted formation of small, equiaxed Cu3Al intermetallic particle in the bulk microstructure, which exhibited much higher hardness and modulus as compared to Cu6Sn5 and β-Sn. On the other hand, minor addition of Zn up to 0.5 % did not lead to the formation Cu-Zn compound, but Zn dissolved in Cu-Sn IMC and formed Cu6(Sn,Zn)5. It was found that Zn tends to accumulate at the edge of solder/MC and especially at the IMC/ Cu interface. Results show that the minor addition of Al and Zn does not alter the morphology of the interfacial intermetallic compounds, but they substantially suppress the growth of the interfacial IMC during reflow and after aging. It is suggested that both Al and Zn exert their influence with different mechanism. Al exerts its influence by lowering the activity of reacting species by its presence at the solder/IMC interface. It was suggested Zn exerts its influence the synergy effect of stabilizing Cu6(Sn,Zn)5 and hindering the flow of reacting species at the solder/IMC and IMC/Cu interface. Nanoindentation results showed that with the addition of Zn, the hardness value Cu6(Sn,Zn)5 of has increased and creep performance of SAC+ Zn in the bulk has improved in comparison to SAC105. Shear strengths for samples with addition of Al and Zn have decreased in comparison to SAC 105 after reflow. Failure mode and mechanisms of SAC 105 and SAC + X (X= Al or Zn) are discussed and compared
Hybrid microwave power amplifiers for broadband communication / Pragash Sangaran
No full textThe software-defined radio is the future of radio technology. The development of a broadband power amplifier is the most challenging radio component to design in achieving software-defined radio goals due to the PA gain-bandwidth limitation. The distributed power amplifier (DPA) overcomes the limitation by combining output power from several transistors in an additive fashion. Matrix Amplifier (MA) consists of two or more DPA stacked together in a multiplicative manner. In this project, a high power and high gain DPA for a two-way radio system is demonstrated. The DPA exhibits 10W output power and 32dB gain across the frequency range of 100MHz to 2GHz. The DPA also has an adjustable inter-stage matching cascaded network. A good correlation between measurement and simulation has been achieved. Simulation guidelines to achieve a good correlation between measurement and simulation are also given in this work. On top of that, the design of a high gain silicon BJT and E-pHEMT hybrid matrix amplifier with novel optimum filter matching technique is demonstrated. Conventional DPA and MA design techniques are only suitable for MMIC implementation because the availability of arbitrary values of lumped element Lc, Ld, Lb, and Cadd is only possible in MMIC technology. Therefore, a novel hybrid MA design and implementation methodology using novel optimum filter matching techniques are demonstrated. In this work, MA exhibits an average gain of 37.5 dB and an average Pout of 18 dBm in the band 0.65-5.8 GHz with 3V supply voltage. The gain is the highest among the state-of-the-art devices in the same frequency range. The bandwidth is 5.15 GHz, and P1dB is 20.3 dBm at 1.35 GHz. The PAE ranges from 10 % to 16 %, and Pdc is 1.2 W
3-dimensional carbon Micro-electro Mechanical System (MEMS) electrode for potential dielectrophoretic hepatic cell patterning application / Wan Nurlina Wan Yahya
Get PDFThe maintenance of liver tissue unique pattern remains a great challenge in the generation of functional engineered liver tissue in vitro. This thesis presents a carbon dielectrophoresis (DEP) based cell patterning for generating hepatic cell constructs, mimicking biological hepatic lobule. A new design of electrode named interdigitated radiating-strips electrode (IRSE) was simulated and optimized using COMSOL Multiphysics 4.2a. The simulation result proved that IRSE is capable to provide uniform distribution of electric field for generating three-dimensional (3D) DEP force. The use of carbon electrodes has been an alternative to traditional metal electrodes and insulator structures for DEP applications since more advantages offered. The proposed lab-on-a chip (LOC) device composed of three layers and feature 3D carbon IRSE which was fabricated using a carbon micro-electro-mechanical system (CMEMS) technique. The electrical characterization result of the fabricated carbon electrode shows that the average electrode resistivity is 10.36 ± 1.19 × 10-4 Ω·m, which low enough to generate an electric field for DEP application using 10 of volts. A proof-of-concept experiment using an interdigitated circular post electrode was conducted to confirm the functionality of the fabricated LOC device. Results show that with the presence of a 15 V voltage input, this carbon structure was capable of manipulating polystyrene microbeads through negative DEP and positive-DEP in a range of frequency. In the guise of IRSE, both two dimensional (2D) and 3D structures were fabricated and 10 µm polystyrene microbeads were used as a model to demonstrate dielectrophoretic cell patterning. Under 15 V of AC signal and 50 MHz of frequency in 1 minute, 3D IRSE shows a 67% increase in trapping efficiency of pDEP microbeads as compared to the 2D IRSE. This result suggests that the 3D carbon electrode has the capacity to generate strong electric field gradients over the microchannel which is in line with the simulation result. Certainly, this CMEMS technique can be utilized to engineer a 3D carbon electrode for DEP application and has a great potential to be applied for 3D hepatic cell patterning. Future applications of the fabricated LOC device include artificial organs for integration in the human-on-a-chip system, drug development, and toxicity screening, as well as the modeling of patient specific liver illness
Penjanaan ekonomi masjid menerusi aktiviti perniagaan: Kajian di masjid-masjid Wilayah Persekutuan Kuala Lumpur / Amru Alhaz Adnan
Get PDFHubungan di antara masjid dan ekonomi amat berkait rapat mengambil kira sebahagian fungsi asalnya sebagai pusat perkembangan ekonomi masyarakat Islam. Namun begitu kebergantungan institusi masjid kepada sumber pendapatan tradisi mengakibatkan institusi masjid tidak mampu melaksanakan fungsinya secara menyeluruh. Oleh yang demikian, penjanaan ekonomi masjid menerusi aktiviti perniagaan merupakan alternatif terbaik dalam memastikan kelestarian sumber pendapatannya. Justeru kajian ini bertujuan untuk menganalisis sumber pendapatan, aktiviti serta faktor kejayaan perniagaan masjid-masjid kariah di Wilayah Persekutuan Kuala Lumpur (WPKL). Dalam kajian ini, data-data penyata kewangan tahunan rasmi selama tiga tahun (2014-2016) bagi dua belas buah masjid yang mewakili enam buah pusat pentadbiran zon di WPKL telah dikumpulkan. Temu bual juga turut dilakukan terhadap dua belas informan yang terlibat langsung dengan pengurusan masjid. Seterusnya data-data terkumpul ini dianalisis menggunakan pendekatan analisis kandungan dan dibuat secara tematik. Hasil kajian menunjukkan sumber ekonomi utama masjid-masjid WPKL adalah bersumberkan pendapatan tradisi di samping sebahagian pendapatan diperoleh menerusi aktiviti perniagaan. Masjid-masjid yang terletak di pusat bandar memperoleh pendapatan perniagaan yang lebih baik berbanding masjid di kawasan perumahan. Selanjutnya, aktiviti perniagaan yang dijalankan oleh masjid didapati terhad kepada sewaan aset fizikal disebabkan oleh kekangan daripada aspek peraturan, persepsi negatif penduduk sekitar dan mentaliti pengurusan masjid. Seterusnya kajian mendapati terdapat empat faktor utama yang mempengaruhi kejayaan aktiviti perniagaan Masjid WPKL iaitu kerjasama kepimpinan masjid, lokasi masjid di kawasan orang ramai, kemudahan akses serta faktor keluasan kawasan masjid. Akhir sekali, kajian ini mencadangkan Garis Panduan Pengurusan Kewangan Masjid dan Surau WPKL ditambah baik agar masjid-masjid dapat mempelbagaikan aktiviti perniagaan untuk menjana ekonomi masjid
Direct and indirect written corrective feedback on the use of past tense amongst ESL learners / Tang Tuck Mun
Get PDFFor decades, a considerable amount of attention has been given to written corrective feedback (WCF) in the field of second language acquisition (SLA). In the early development of WCF, Truscott (1996) raised a few theoretical issues which led studies on WCF to be carried by researchers opposing his claims. He claimed that 1) a simple transfer of information cannot be expected to be beneficial due to the well-established SLA insights about the complex and gradual nature of the process of acquisition, 2) if WCF approach is employed at a time that is not consistent with the natural order, it could not be effective and 3) an ESL learner learns anything from the employment of WCF approach, the learning is likely to be only ‘pseudo-learning.’ Hence, this study aimed to explore the extent to which ESL learners’ accuracy in past tense use improves as a result of direct and indirect WCF and other factors that may contribute to ESL learners’ accuracy in past tense use resulting from direct and indirect WCF. A mixed-method design was employed in this study. Quantitative data was collected using a pre-test, an immediate post-test, and a delayed post-test whilst qualitative data was collected via interviews. A total of eighty UM undergraduates took part in this study, and they were divided into two treatment groups equally. Both groups were given direct and indirect WCF, respectively. The analysed quantitative data showed that the direct WCF group performed better than the indirect WCF group. As for the qualitative data, three main themes (factors) emerged from the thematic analysis. They were learners’ attitudes toward the WCF provided, learners’ thinking effort, and scaffolding. Findings from this study cannot be generalised as the study collected data only from one local university in Malaysia
Persuasive strategies in the English translations of the al-Baqarah Quranic verses / Dalal A. S. Aldahshan
Get PDFThe persuasive act refers to the performance of an act with the use of a specific form of communication through language, one of the most essential factors used in influencing people's thoughts and attitudes, setting decisions and controlling values. The persuasive act can be used in many ways by influencing the thoughts and behavior of people or in advertisement which sell products or services by way of convincing people to buy certain products or services. In politics, it is also used to convince people to change their political beliefs or ideologies. On the religious side, the persuasive act is considered as one of the most effective methods used to convince the reader to adopt and observe certain religious beliefs and practices. This research aims to explore the various persuasive speech acts used in the longest chapter of the Holy Qur'an, that is, Surah (Chapter) Al-Baqarah. This study also attempts to describe and identify the rhetorical devices used in the acts of persuasion found in the chapter. By carrying out a pragmatic analysis based on Searle's classifications of speech acts (1979) and Johnstone's techniques of persuasion (2008), the data is analyzed linguistically by identifying the types of persuasive acts and the rhetorical devices used as strategies and techniques of persuasion. The results reveal that the speech act classes of assertives, directives and commissives are used in the Al-Baqarah chapter as persuasive strategies. Assertives are used to assert beliefs or to confirm and emphasize facts whereas directives are used to command, suggest, recommend or to encourage the reader as means to influence their attitudes or to perform actions of the persuasive discourse. The commissive type is also used as a means of persuasion through giving promises and encouraging the readers to perform certain actions. It is also found that there are combinations of two persuasive acts in one verse such as the assertive and directive types, the assertive and commissive types and the directive and commissive types. The findings also demonstrate the use of three persuasive techniques; quasilogical, presentational and analogical. Quasilogical argumentation, which is based on rationality, is utilized via conditional clauses, logical connectives and rhetorical question. To create involvement, the presentational persuasion is manipulated via repetition, rhetorical deixis and similes. The analogical technique of persuasion is also employed in the Holy Qur'an that is exemplified by the use of stories of the prophets