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Personality affected robotic emotional model with associative memory for human-robot interaction
No full textThe decision making process in communication is affected by internal and external factors from dynamic environments. Humans can perform a variety of behaviors in a similar situation, unlike robots. This paper discusses human psychological phenomena during communication from the point of view of internal and external factors, such as perception, memory, and emotional information. Based on these, we introduce the personality affected robotic emotional model and the emotion affected associative memory model for the robot. We organize an interactive robot system to provide suitable decisions for the robot. Results from interactive communication experiments indicate that the robot is able to perform different actions based on internal and external factors
Effects of pH, UV-B radiation and NaCl on anthocyanin stability from vivid blue petals of Clitoria ternatea L., a potential natural colourant from legume crop
No full textPurpose: The purpose of this study is to investigate the effects of pH, UV-B radiation and NaCl on anthocyanin extracted from vivid blue petals of Clitoria ternatea L. (legume crop), as a potential natural colourant for food, dye or coating technology. Design/methodology/approach: The anthocyanin from petals of Clitoria ternatea was extracted using 0.5 per cent trifluroacetic (TFA) in methanol solution. The liquid colourant was exposed to different pH (1, 4.5 and 5.5), UV-B radiation and sodium chloride (NaCl). The results were compared using UV-vis spectrophotometric analysis. Findings: Anthocyanins are sensitive and quickly degrade in the presence of light. In the dry powder form, the anthocyanin is easier to maintain and preserve (storage). Research limitations/implications: Anthocyanins extracted from vivid blue petals of Clitoria ternatea L. are sensitive and quickly degrade in the presence of light. Practical implications: The anthocyanin pigments extracted from Clitoria ternatea L. petals with methanolic acid were successfully coated on glass slides. The combination of binders and pigments had produced environmental paint which added with stabilisers (additives) for better durability. Acrylic has been known for its high weathering and embrittlement resistance, good mechanical and electrochemical properties and gloss retention. Social implications: This anthocyanin is suitable as natural colourant especially in baby products, cosmetics production or for coating and varnish application. Originality/value: Till date, the natural colourant of Clitoria ternatea L. petals is widely used in food. However, this result is a new finding, as there is no report on the potential of applications of this natural colourant for coating technology. Therefore, the current study with appropriate extraction method was significantly based on the relevant literatures of coating production from pigment by using other plant species. The findings and conclusion highlight the practicality as the potential applications in coating technology
A novel design of a low-voltage low-loss T-match RF-MEMS capacitive switch
No full textThis paper presents a novel design, optimization and analysis of capacitive radio frequency (RF) micro-electromechanical system (MEMS) switch. The design incorporates a novel membrane and beams’ structure with two short high-impedance transmission-line (T-line) sections added on either side of the switch (namely T-match switch) to improve its RF performance, while maintaining low-actuation voltage. The short high-impedance T-line section has narrower width and higher impedance than the coplanar waveguide (CPW)’s signal line, behaves as series inductor to compensate the switch’s up-state capacitance and provides excellent matching at the design frequency. This high-impedance T-line section was designed, simulated and optimized using finite-element-modelling (FEM) tool of electromagnetic (EM) simulator of AWR Design EnvironmentTM. The optimized T-line section’s width and length is 10 µm and 70 µm, respectively. The RF-MEMS switch is actuated by electrostatic force with low-actuation voltage of 2.9 V, has maximum von Mises stress of 13.208 MPa which is less than aluminium’s yield stress and can be operated in robust conditions. Compared to the normal capacitive RF-MEMS switch, this T-match capacitive RF-MEMS switch with two sections of optimized high-impedance T line has improved the performance of return loss and insertion loss, at switch-on state, by 45.83% and 55.35%, respectively; while at the switch-off state, the isolation is increased by 24.05%; only the switch-off return loss is degraded by 11.7% but the value (− 0.5519 dB) is still located in the range of design specifications. The RF-MEMS switch’s actuation time was simulated to be ~ 27 µs with amplitude of 5 V up-step voltage
The effects of planning conditions on primary school ESL pupils' narrative writing
No full textThe present study investigates the writing performance in terms of language complexity, accuracy and fluency (CAF) and the pupils' perceptions of their performance under different planning conditions and the relationship between pupils' perceptions and their performance. There were 78 ESL pupils from a Chinese primary school in Malaysia who were grouped into three planning conditions:1) pre-task planning, 2) on-line planning and 3) no planning groups. This study employs a variety of data collection methods that include the collection of pupils' written tasks and questionnaire surveys. The results of the study indicate that planning conditions did not have a significant impact on pupils' writing performance except for the effect of pre-task planning on pupils' written fluency. The results also differ greatly from numerous previous studies, which have been mainly conducted on adult writers. The present study also shows that pupils' perceptions are partially related to their writing performance. The reasons for such contradictions are discussed. The findings have implications for the teaching of writing in the ESL context
Facile solvothermal designing of graphene/Ni3V2O8 nanocomposite as electrode for high performance symmetric supercapacitor
No full textIn the present study, graphene/Ni3V2O8 nanocomposites were successfully synthesised by a facile solvothermal approach in which the graphene sheets were fabricated via the environmentally benign liquid phase exfoliation with optimised ethanol to water volume ratio (2:3). The nanocomposites integrated separately the advantages of graphene sheet and pseudocapacitive nature of Ni3V2O8 and hence possessed electrochemical performance which outperformed the pristine Ni3V2O8. Optimizations on the weight ratio between the graphene and Ni3V2O8 were performed to determine the synergistic effect between the highly conductive graphene sheet and Ni3V2O8. Among the graphene/Ni3V2O8 nanocomposites, G-4NVO (graphene/Ni3V2O8 with the weight ratio of 1:4) was proved to be a promising electrode material, as it delivered eminent specific capacitance of 748 Fg−1 at current density of 0.5 Ag-1, remarkable energy density of 103.94 Wh/kg at power density of 45.61 kW/kg, reasonable cycling stability with 71% capacitance retention and superior coulombic efficiency of 83% after 3000 charge-discharge cycles at 0.5 Ag-1
Paenibacillus lautus, an opportunistic bacterial pathogen, isolated from Ixodes granulatus Supino (Acari: Ixodidae) collected from a Müller’s giant Sunda rat (Sundamys muelleri)
No full textWild rodents are carriers of ectoparasites such as ticks that are vectors of infectious diseases with human and veterinary significances. Due to their close association with human dwellings, synanthropic wild rodents may aid the spread and transmission of tick-borne pathogens. In light of this, an effort was initiated to study the cultivable bacteria within ticks collected from wild rodents trapped in Sungai Congkak Recreational Forest, Selangor. Ticks collected from four different rodent species; Sundamys muelleri, Maxomys whiteheadi, Maxomys rajah and Rattus rattus, were sterilely homogenized and cultured. One unique bacterial isolate originating from an engorged adult female Ixodes granulatus Supino collected off a Sundamys muelleri rat was identified as Paenibacilus lautus via 16S rDNA, ctpA sequencing and biochemical tests. Antimicrobial susceptibility testing revealed that the P. lautus isolate was resistant to ampicillin, penicillin, clindamycin, chloramphenicol, rifampicin and trimethoprim-sulfamethoxazole, mirroring the antimicrobial susceptibility profiles of clinical strains. Recovery of this opportunistic bacterial pathogen from the tick suggests that it may be transmitted to humans or other hosts through tick bites and cause disease once it enters the bloodstream. Therefore, it is important to remain vigilant due to its pathogenic potential and improve our waste disposal practices to avoid attracting rodents
Inadequate water treatment quality as assessed by protozoa removal in Sarawak, Malaysia
No full textProviding safe drinking-water to human civilization is indispensable; it is one of the most cost-effective means of reducing the disease burden of diarrhea. Unfortunately, water supply quality monitoring from public water treatment plants (WTPs) is often neglected or taken for granted. To determine the produced water quality, WTPs in Sarawak, Malaysia were assessed for their protozoa removal ability. A selfadministered questionnaire based on the regulations in the Drinking-water Standards for New Zealand (DWSNZ) was developed. Optional 10-liter raw water samples were collected from willing WTPs for the detection of protozoan cysts. Routine physical and microbial testing of WTP parameters were also requested for raw water quality overview. Two of the nine assessed WTPs achieved three log credits in the treatment component, one of which belonged to Peninsular Malaysia. No log credits were obtained in the other tested components for any samples. Most of the WTPs employed "Coagulation, Sedimentation, and Filtration" using rapid gravity filters without enhancement (P < 0.05). Giardia cysts were detected in raw water sources used for treatment, and the geographical location was identified as an influencing factor for raw water quality. There is an urgent requirement for active collaboration and holistic approaches to review existing water management policies and interventions. WTPs in Sarawak did not achieve the log credits required to safeguard the microbial quality of the water supplied; however, only Giardia cysts were detected in 10-liter raw water samples despite routine microbial parameter monitoring showing disturbing contamination levels
Chronic administration of sodium nitrite prevents hypertension and protects arterial endothelial function by reducing oxidative stress in angiotensin II-infused mice
No full textAim: Endothelial dysfunction accompanied by an increase in oxidative stress is a key event leading to hypertension. As dietary nitrite has been reported to exert antihypertensive effect, the present study investigated whether chronic oral administration of sodium nitrite improves vascular function in conduit and resistance arteries of hypertensive animals with elevated oxidative stress. Methods: Sodium nitrite (50 mg/L) was given to angiotensin II-infused hypertensive C57BL/6J (eight to ten weeks old) mice for two weeks in the drinking water. Arterial systolic blood pressure was measured using the tail-cuff method. Vascular responsiveness of isolated aortae and renal arteries was studied in wire myographs. The level of nitrite in the plasma and the cyclic guanosine monophosphate (cGMP) content in the arterial wall were determined using commercially available kits. The production of reactive oxygen species (ROS) and the presence of proteins (nitrotyrosine, NOx-2 and NOx-4) involved in ROS generation were evaluated with dihydroethidium (DHE) fluorescence and by Western blotting, respectively. Results: Chronic administration of sodium nitrite for two weeks to mice with angiotensin II-induced hypertension decreased systolic arterial blood pressure, reversed endothelial dysfunction, increased plasma nitrite level as well as vascular cGMP content. In addition, sodium nitrite treatment also decreased the elevated nitrotyrosine and NOx-4 protein level in angiotensin II-infused hypertensive mice. Conclusions: The present study demonstrates that chronic treatment of hypertensive mice with sodium nitrite improves impaired endothelium function in conduit and resistance vessels in addition to its antihypertensive effect, partly through inhibition of ROS production
Blockchain technology the identity management and authentication service disruptor: A survey
No full textThe Internet today lacks an identity protocol for identifying people and organizations. As a result, service providers needed to build and maintain their own databases of user information. This solution is costly to the service providers, inefficient as much of the information is duplicated across different providers, difficult to secure as evidenced by recent large-scale personal data breaches around the world, and cumbersome to the users who need to remember different sets of credentials for different services. Furthermore, personal information could be collected for data mining, profiling and exploitation without users' knowledge or consent. The ideal solution would be self-sovereign identity, a new form of identity management that is owned and controlled entirely by each individual user. This solution would include the individual's consolidated digital identity as well as their set of verified attributes that have been cryptographically signed by various trusted issuers. The individual provides proof of identity and membership by sharing relevant parts of their identity with the service providers. Consent for access may also be revoked hence giving the individual full control over its own data. This survey critically investigates different blockchain based identity management and authentication frameworks. A summary of the state-of-the-art blockchain based identity management and authentication solutions from year 2014 to 2018 is presented. The paper concludes with the open issues, main challenges and directions highlighted for future work in this area. In a nutshell, the discovery of this new mechanism disrupted the existing identity management and authentication solutions and by providing a more promising secure platform
Effect of various refining processes for Kenaf Bast non-wood pulp fibers suspensions on heat transfer coefficient in circular pipe heat exchanger
No full textHeat transfer coefficients were obtained for a range of non-wood kenaf bast pulp fiber suspensions flowing through a circular pipe heat exchanger test loop. The data were produced over a selected temperature and range of flow rates from the flow loop. It was found that the magnitude of the heat transfer coefficient of a fiber suspension is dependent on characteristics, concentration and pulping method of fiber. It was observed that at low concentration and high flow rates, the heat transfer coefficient values of suspensions were observed higher than that of the heat transfer coefficient values of water, on the other hand the heat transfer coefficient values of suspensions decreases at low flow rates and with the increase of their concentration. The heat transfer were affected by varying fiber characteristics, such as fiber length, fiber flexibility, fiber chemical and mechanical treatment as well as different pulping methods used to liberate the fibers. Heat transfer coefficient was decreased with the increase of fiber flexibility which was also observed by previous researchers. In the present work, the characteristics of fibers are correlated with the heat transfer coefficient of suspensions of the fibers. Deviations in fiber properties can be monitored from the flowing fiber suspensions by measuring heat transfer coefficient to adjust the degree of fiber refining treatment so that papers made from those fibers will be more uniform, consistent, within the product specification and retard the paper production loss