Qualitative phase space modeling of non-linear electrical dynamic systems

The purpose of this paper is to combine the existing methodologies that describe non-linear dynamic systems, by using the phase space and the descriptions of qualitative behaviors of ordinary differential equations. The swing equation of a synchronous machine has been illustrated as an example.published_or_final_versio

A Case of Bowen’s Disease and Small-Cell Lung Carcinoma: Long-Term Consequences of Chronic Arsenic Exposure in Chinese Traditional Medicine

Chronic arsenic toxicity occurs primarily through inadvertent ingestion of contaminated water and food or occupational exposure, but it can also occur through medicinal ingestion. This case features a 53-year-old lifetime nonsmoker with chronic asthma treated for 10 years in childhood with Chinese traditional medicine containing arsenic. The patient was diagnosed with Bowen’s disease and developed extensive-stage small-cell carcinoma of the lung 10 years and 47 years, respectively, after the onset of arsenic exposure. Although it has a long history as a medicinal agent, arsenic is a carcinogen associated with many malignancies including those of skin and lung. It is more commonly associated with non–small-cell lung cancer, but the temporal association with Bowen’s disease in the absence of other chemical or occupational exposure strongly points to a causal role for arsenic in this case of small-cell lung cancer. Individuals with documented arsenic-induced Bowen’s disease should be considered for more aggressive screening for long-term complications, especially the development of subsequent malignancies

Persepsi guru dan pelajar terhadap persekitaran pembelajaran konstruktivisme untuk mata pelajaran Teknologi Maklumat dan Komunikasi

The purpose of this study was to assess teacher’s and student’s perceptions of constructivist learning environments for the subject Information Technology and Communication (ICT) at national secondary schools in Klang Valley. Teacher’s and student’s perceptions were measured in terms of five dimensions — Personal Relevance, Uncertainty, Critical Voice, Shared Control and Student Negotiation. A total of 440 students and 74 teachers were involved in this study. The results of this study showed that teachers and students considered the existence of the constructivist learning environment to be at the moderate level. In other words, the results suggest that constructivism is not practiced so effectively in the ICT teaching-learning environment. The results of the study also suggest that the majority of teachers and students perceived ICT as a subject that is ever changing but they do not perceive that students have shared control over their learning

Fabrication of Photovoltaic Cell From Rhenium Containing Polymer

Photovoltaic devices were fabricated using rhenium bis(arylimino) acenaphthene (DIAN) complex containing poly(p-phenylenevinylene). These polymers absorb strongly in the visible region at ca. 440-550 nm. In addition, this type of transition metal based polymers have been shown to exhibit large photo-sensitivity due to the presence of the rhenium complex, which has a relatively long-lived Metal-to-Ligand Charge Transfer (MLCT) character. By using this type of polymers, the metal content can be adjusted easily by simply changing the monomer feed ratio. Moreover, the excited state properties and electronic absorption properties can be modified by varying the structure of the diimine ligand coordinated to the metal. This approach allows us to fine-tune the absorption spectra of the polymers by employing different types of rhenium complex derivatives. PEDOT:PSS and PTCDI were used as the hole and electron transport layers, respectively. The ITO/PEDOT:PSS/DIAN-PPV/PTCDI/Al devices were found to exhibit photovoltaic response under the illumination of AMI solar radiation. The short-circuit current ISC, open-circuit voltage V OC, and the fill factor FF were measured to be 38 μA/cm 2, 0.93 V and 0.21 respectively. Another photovoltaic device was prepared with the structure ITO/PEDOT:PSS/DIAN-PPV:TiO2/PTCDI/Al and its photovoltaic properties were studied. The presence of TiO2 will assist the electron transport of the DIAN-PPV to the PTCDI, in which the electrons can be collected at the aluminium electrode. The short-circuit current ISC open-circuit voltage VOC, and the fill factor FF were measured to be 51 μA/cm2, 1.18 V and 0.12 respectively. It was observed that the power conversion efficiency of photovoltaic devices related closely to the rhenium content and the structure of the rhenium complex used.published_or_final_versio

Analytic eye movement patterns in face recognition are associated with better performance and more top-down control of visual attention: an fMRI study

Conference Theme: Integrating Psychological, Philosophical, Linguistic, Computational and Neural PerspectivesPoster Session 3: no. 57Recent research has revealed two different eye movement patterns during face recognition: holistic and analytic. The present study investigated the neural correlates of these two patterns through functional magnetic resonance imaging (fMRI). A more holistic pattern was associated with more activation in the face-selective perceptual areas, including the occipital face area and fusiform face area. In contrast, participants using a more analytic pattern demonstrated more activation in areas important for top-down control of visual attention, including the frontal eye field and intraparietal sulcus. In addition, participants using the analytic patterns had better recognition performance than those showing holistic patterns. These results suggest that analytic eye movement patterns are associated with more engagement of top-down control of visual attention, which may consequently enhance recognition performance.postprin

Fabrication of organic photovoltaic devices by the layer-by-layer polyelectrolyte deposition method

Organic photovoltaic cells were fabricated by the layer-by-layer polyelectrolyte deposition process by which the film thickness can be controlled accurately. Ruthenium/rhenium complexes containing poly(p-phenylenevinylene) and sulfonated polyaniline were used in the process. This new method provides flexibility in the fabrication of multilayer polymeric devices with well-defined structure. © 2005 IEEE.published_or_final_versio

A study of perceived ICT learning environments in Malaysian secondary schools

This study seeks to investigate the extent to which the teaching and learning practices of a discrete Information and Communication Technology (ICT) subject are in accordance with the constructivist nature of ICT as perceived by Malaysian secondary school students. A survey methodology was employed such that modified items from the Constructivist Learning Environment Survey (CLES) questionnaire were adopted. It comprised five components of constructivist learning: Personal Relevance, Uncertainty of ICT, Shared Control, Critical Voice and Student Negotiation. Data were gathered from 440 participants. Findings from the present study indicate that three out of five components are sufficiently present in the ICT learning environment (Personal Relevance, Uncertainty of ICT and Student Negotiation). The other two components (Shared Control and Critical Voice), however, were not encouragingly present despite the positive intentions of the ICT curriculum

Does Information and Communications Technology (ICT) Development Foster Economic Growth of ASEAN5 +3 Countries?

Globally, digital technologies affect lifestyles, norms and business restructuring models. Correspondingly, it plays a significant role in fostering the economic growth of Association of South East Asian Nations (ASEAN) as well as Asian countries at large. This study aims to investigate the impact of ICT development on the economic growth of the ASEAN5 +3 nations over the period of 2011 to 2018. ASEAN5+3 comprises of eight nations namely Malaysia, Singapore, Philippines, Thailand, Indonesia, China, South Korea and Japan. Themethodologies applied in this study include panel data regression analysis and several diagnostic tests such as the Hausman test and the Breusch-Pagan Lagrange multiplier (BPLM) test. The empirical results suggest there is a positive significant relationship between ICT development and economic growth among the ASEAN5 +3 countries. This relationship can be further strengthened through various policy implementations such as governmental investments. The results of this study imply that these Asian countriesare growing in consistence with information technology (IT)-led development

Fabrication of bulk heterojunction photovoltaic devices using sublimable rhenium diimine complexes as photosensitizers

A series of chlorotricarbonyl rhenium (I) bis(phenylimino)acenaphthene (Re-DIAN-X) complexes were used as the photosensitizers for photovoltaic cells. Unlike other transition-metal-based photovoltaic sensitizers that can only be prepared by solution method, these complexes are sublimable. Compared to other rhenium diimine complexes based on bipyridine or 1,4-diaza-1,3-butadiene ligands, these complexes have lower band gaps, which can be modified easily by changing the structure of the ligand. It allows the preparation of blend of metal complexes in order to broaden the sensitization region in UV-vis absorption spectrum. One of the complexes also shows bipolar charge transport character with relatively high charge carrier mobilities in the order of 10 -3 cm2V-1s-1. Multilayer heterojunction and bulk heterojunction devices with fullerene as the electron accepting molecule were prepared. For the bulk heterojunction devices, the fill factor and power conversion efficiency under AM 1.5 simulated solar light illumination were 0.51 and 1.29 %, respectively. The effects of changing the Re-DIAN/C60 film thickness, Re-DIAN/C60 ratio and variation of ligand structures in the bulk heterojunction devices were studied. The amount of photosensitizer and electron transport molecules may strongly affect the balance between the photon absorption, exciton formation, dissociation, and charge transport processes. Atomic force microscopic images showed that the complex dispersed evenly with fullerene molecules in solid state.published_or_final_versio

The use of sublimable chlorotricarbonyl bis(phenylimino)acenaphthene rhenium(I) complexes as photosensitizers in bulk-heterojunction photovoltaic devices

A series of sublimable substituted chlorotricarbonyl bis(phenylimino)acenaphthene rhenium(I) complexes was synthesized and used in the fabrication of photovoltaic devices. The hole and electron carrier mobilities of these complexes are in the order of 10-3 to 10-4 cm2 V-1 s-1. Heterojunction devices with CuPc/complex/C60 (CuPc = copper phthalocyanine) as the active layer and bulk heterojunction devices with complex:C60 as the active layer were fabricated. The rhenium complexes function as photosensitizer in the devices, and exhibit optical absorption in the region between 500 and 550 nm within which other components in the device do not absorb. Other devices with hole transport materials, exciton blocking materials, and different active layer thickness were also fabricated. Variation of substitution groups in the ligand did not show significant difference in device performance. The best power conversion efficiency of the devices was measured to be 1.29% under illumination of AM1.5 simulated solar light. © 2009 Elsevier B.V. All rights reserved.postprin