189 research outputs found

    Graphical User Interface (GUI) Controlled Mobile Robot

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    The advanced design and development of robotic technology in producing multi task are increasingly. In this paper presents about designing and developing mobile robot model that can be controlled using Graphical User Interface (GUI) via wireless protocol. This paper focuses on the control mobile robot by using the GUI as navigation control and the user can get a view an image and real time video on visual basic software. To address the problem of sired based control, XBee wireless communication circuit was used in mobile robot through a computer command. The development of this mobile robot consists of a chassis, a graphical user interface (GUI), XBee module, DC gear motor, camera, track wheels and microcontroller type PIC18F4550. Differential driving method using L298 circuit was used to control movement of the robot. In mechanical design, the wheel track has been used instead of conventional wheels to enable the robot to travel through different types of surfaces or rough terrain. In addition, wireless cameras was attached to the robot as a system of monitoring function. Finally, the robot will be designed to control wireless remote control that can control robots. Wireless remote control allows the user of an environment that is unsafe or dangerous device and evades wires or cables interfere with the movement of the robot

    Development of Portable Air Conditioning System Using Peltier and Seebeck Effect

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    The society bustle factor in this day and age, most people want to find equipment that is often used in everyday life in a small and light weight design. The purpose of this project is to develop portable air conditioning system without using any gas. The system used thermoelectric heat pump as main device for producing cool air known as Peltier Effect. The generating system theoretically can recycle the heat loss to produce additional electricity for other usage. The efficacy of this system tested using two types of experimental using Peltier and Seebeck Effect. Both experimental are conducted using 3 specific volumes; 1) 1000cm3; 2) 4000cm3; and 3) 9000cm3. As a result, temperature for heating and cooling systems achieve around 16 – 40 degree Celcius (oC) while the voltage generated around 12V in 30 minutes

    Squirrel cage induction motor scalar control constant V/F analysis

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    In constant V/f control technique it is assume that the stator resistance and leakage inductance drops are negligible, especially at high speed and small load. In other words, the back emf is comparatively large at high speed and hence these voltage drops can be neglected. By maintaining constant V/f, constant Eg/f and hence constant air-gap flux is assumed. This assumption is however invalid at low speeds since a significant voltage drop appears across the stator impedance. The terminal voltage, V no longer approximates ag. By using MATLAB Simulink, the open-loop constant V/f is simulated. It is shown that the performance of the drive deteriorates at low speeds. The improvement in the performance by applying voltage boost is shown and discussed

    Porous amphiphilic biogel from facile chemo-biosynthetic route

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    Grafting of medium-chain-length poly-3-hydroxyalkanoates (mcl- -PHA) with glycerol 1,3-diglycerolate diacrylate (GDD) in acetone was performed using benzoyl peroxide as the initiator. A detailed mechanism scheme provides significant improvement to previous literature. Radical-mediated grafting generated –carbon inter-linking of mcl-PHA and GDD, resulting in a macromolecular structure with gel properties. The thermal properties of the copolymer for different graft yields were investigated as a function of initiator concentration, GDD monomer concentration, incubation period and temperature. The water absorption and porosity of the gel were significantly improved relative to neat mcl-PHA

    Ownership structure, risk taking and firm performance: a case for an integrative framework

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    Studies on ownership structure and firm performance are inexhaustible. This is due to the growing contradictory, inconclusive and inconsistent empirical findings which give rise to growing concerns and suggestions for the integration of latent variables to best explain the observed unclear relationship. This would mean adopting more of an integrated (moderation or mediation) rather than direct research framework in an attempt to explain the relationship between ownership structure and firm's performance better. This paper thus examined the ownership structure and firm performance with risk-taking behaviour as a moderator. As conceptual paper, a review of agency and stewardship theories as well as prospect theory along with each dimension of ownership structure is conducted. From the extensive review, it was found that risk taking is an integral part of organizational life. Consequently, an integrative framework that incorporates risk-taking as a moderator in the relationship between ownership structure and firm performance is proposed. This paper concluded that the application of this framework would offer better explanation of the relationship between ownership structure and firm performance taking into account the risk preferences of the enterprise

    Identification of the genomic mutation in Epha4rb-2J/rb-2J mice

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    The EphA4 receptor tyrosine kinase is involved in numerous cell-signalling activities during embryonic development. EphA4 has the ability to bind to both types of ephrin ligands, the ephrinAs and ephrinBs. The C57BL/6J-Epha4rb-2J/GrsrJ strain, denoted Epha4rb-2J/rb-2J, is a spontaneous mouse mutant that arose at The Jackson Laboratory. These mutants exhibited a synchronous hind limb locomotion defect or “hopping gait” phenotype, which is also characteristic of EphA4 null mice. Genetic complementation experiments suggested that Epha4rb-2J corresponds to an allele of EphA4, but details of the genomic defect in this mouse mutant are currently unavailable. We found a single base-pair deletion in exon 9 resulting in a frame shift mutation that subsequently resulted in a premature stop codon. Analysis of the predicted structure of the truncated protein suggests that both the kinase and sterile α motif (SAM) domains are absent. Definitive determination of genotype is needed for experimental studies of mice carrying the Epha4rb-2J allele, and we have also developed a method to ease detection of the mutation through RFLP. Eph-ephrin family members are reportedly expressed as numerous isoforms. Hence, delineation of the specific mutation in EphA4 in this strain is important for further functional studies, such as protein–protein interactions, immunostaining and gene compensatory studies, investigating the mechanism underlying the effects of altered function of Eph family of receptor tyrosine kinases on phenotype

    Social role of microfinance institutions in poverty eradication: evidence from ASEAN-5 countries

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    Banking institutions have witnessed the failure of poverty reduction due to high risk service for poor people. Microfinance institutions (MFIs) were developed to provide financial services for low income households. In the drive to supply continuous financial services for the poor, performance of the MFIs has been one of the crucial aspects that needs consideration. The MFIs began with a social goal aim of poverty reduction. However, the commercialization of the MFIs has resulted in them becoming financially independent as they are funded by a previous government. Today the MFIs need to retain the social role, to eradicate poverty whilst at the same time they must strive to sustain long term operation. Are the MFIs still able to sustain their social goals when they also need to focus on financial sustainability? This study proposes to determine the level of social efficiency among MFIs in ASEAN 5 countries as the first objective. Secondly it will examine the impact firm characteristics that internally influence the social efficiency of the MFIs. The data consists of 168 MFIs from Southeast Asia that covers five countries from the year 2011 to 2017. The first stage of analysis to identify the level of social efficiency by using non parametric Data Envelopment Analysis (DEA) approach. The second stage of analysis is to examine the impact of firm characteristics to influence the social efficiency by applying Multivariate Panel Regression Analysis (MPRA) as an estimation method. The findings reveal the MFIs in ASEAN 5 countries have a lower social efficiency. This indicates the MFIs in ASEAN 5 countries has traded their original mission of poverty reduction to focus more on achieving financial sustainability for long term viability

    NuSTAR Survey of Obscured Swift/BAT-selected Active Galactic Nuclei. II. Median High-energy Cutoff in Seyfert II Hard X-Ray Spectra

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    Broadband X-ray spectroscopy of the X-ray emission produced in the coronae of active galactic nuclei (AGNs) can provide important insights into the physical conditions very close to their central supermassive black holes. The temperature of the Comptonizing plasma that forms the corona is manifested through a high-energy cutoff that has been difficult to directly constrain even in the brightest AGN because it requires high-quality data at energies above 10 keV. In this paper we present a large collection of coronal cutoff constraints for obscured AGNs based on a sample of 130 AGNs selected in the hard X-ray band with Swift/BAT and observed nearly simultaneously with NuSTAR and Swift/XRT. We find that under a reasonable set of assumptions regarding partial constraints the median cutoff is well constrained to 290 ± 20 keV, where the uncertainty is statistical and given at the 68% confidence level. We investigate the sensitivity of this result to our assumptions and find that consideration of various known systematic uncertainties robustly places the median cutoff between 240 and 340 keV. The central 68% of the intrinsic cutoff distribution is found to be between about 140 and 500 keV, with estimated uncertainties of 20 and 100 keV, respectively. In comparison with the literature, we find no clear evidence that the cutoffs in obscured and unobscured AGNs are substantially different. Our analysis highlights the importance of carefully considering partial and potentially degenerate constraints on the coronal high-energy cutoff in AGNs

    Effect of iridium loading on the formation of protonic acid sites over Ir/PtHZSM5

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    The Ir/Pt-HZSM5 with different iridium loading (0.3-1.0 wt%) was prepared by impregnation of iridium on Pt-HZSM5. The acidic properties of Ir/Pt- HZSM5 were studied by FTIR spectroscopy, while the activity of the catalysts was tested for n-pentane isomerization in a microcatalytic pulse reactor. The IR results of adsorbed 2,6-lutidine showed that all catalysts possessed strong Brönsted and Lewis acid sites in the outgassing at 473 K and below. When Ir/Pt-HZSM5 was heated in hydrogen, protonic acid sites were formed with concomitant decrease of Lewis acid sites. An increase in iridium loading continuously decreased the Lewis and Brönsted acid sites and inhibited the formation of protonic acid sites induced by hydrogen. The formation of protonic acid sites induced by hydrogen was also confirmed by the formation of electron detected by ESR spectroscopy. Additionally for n-pentane isomerization, an increase in iridium loading decreased the yield of isopentane due to the inhibition in the formation of protonic acid sites via hydrogen spillover phenomenon
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