1,443 research outputs found

    Kinetics and isotherm studies of methyl orange adsorption by a highly recyclable immobilized polyaniline on a glass plate

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    AbstractImmobilized polyaniline on glass plates (PANI/glass) and its powder form were compared for the adsorption of methyl orange (MO) dye from aqueous solutions. The effects of operational parameters such as pH, sorbent dosage, initial concentration, contact time, aeration rate and the thermodynamics of the uptake of MO had been exhaustively evaluated. The maximum adsorption capacity (qmax) for PANI/glass and PANI powder was 93 and 147mgg−1, respectively. In addition, pseudo-second order model was the best fitted kinetic model for both systems, suggesting that the rate-limiting step may be chemisorptions. The obtained negative values of free energy and enthalpy indicated the adsorption process was spontaneous and exothermic. In contrast to PANI powder, PANI/glass yielded negative entropy. Photocatalytic regeneration of used PANI/glass was found to be highly effective where the desorbed MO was completely mineralized. This study showed that immobilized PANI offered the unique advantage of convenient use and reuse over an extended period of applications

    An Effective Noise Adaptive Median Filter for Removing High Density Impulse Noises in Color Images

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    Images are normally degraded by some form of impulse noises during the acquisition, transmission and storage in the physical media. Most of the real time applications usually require bright and clear images, hence distorted or degraded images need to be processed to enhance easy identification of image details and further works on the image. In this paper we have analyzed and tested the number of existing median filtering algorithms and their limitations. As a result we have proposed a new effective noise adaptive median filtering algorithm, which removes the impulse noises in the color images while preserving the image details and enhancing the image quality. The proposed method is a spatial domain approach and uses the 3×3 overlapping window to filter the signal based on the correct selection of neighborhood values to obtain the effective median per window. The performance of the proposed effective median filter has been evaluated using MATLAB, simulations on a both gray scale and color images that have been subjected to high density of corruption up to 90% with impulse noises. The results expose the effectiveness of our proposed algorithm when compared with the quantitative image metrics such as PSNR, MSE, RMSE, IEF, Time and SSIM of existing standard and adaptive median filtering algorithms

    Kajian literatur istilah ‘Umran Ibn Khaldun / Abdul Qayuum Abdul Razak and S. Salahudin Suyurno

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    Kajian ini membincangkan tinjauan literatur terhadap istilah ‘umran Ibn Khaldun yang dicipta dalam karya agung beliau iaitu Muqaddimah. Selain itu, ia bertujuan untuk membincangkan beberapa kajian kontemporari berkaitan kajian ke’umranan. Metode kajian adalah menggunakan pendekatan induktif dan deduktif. Dapatan mendapati bahawa kajian sarjana tertumpu kepada pengistilahan perkataan ‘umran. Selain itu, para sarjana turut menginovasi istilah ‘umran dalam hal ehwal perancangan masyarakat seperti teori perbandaran dan sebagainya

    Going beyond the disability-based morbidity definition in the compression of morbidity framework

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    Background: As originally proposed by Fries, conceptualizing morbidity solely through associated functional limitation/disability (FL/D) remains the most widely accepted metric to assess whether increases in longevity have been accompanied by a compression of morbidity. Objective: To propose a departure from a highly restrictive FL/D-based definition of “morbidity” to a broader view that considers the burden of chronic diseases even when no overt FL/D occur. Design: We outline three reasons why the current framework of compression of morbidity should be broadened to also consider morbidity to be present even when there are no overtly measurable FL/D. We discuss various scenarios of morbidity compression and morbidity expansion under this broader rubric of morbidity. Conclusion: The rationale to go beyond a purely FL/D-based definition of morbidity includes: (1) substantial damage from chronic disease that can develop prior to overt FL/D symptoms occurring; (2) multiple costs to the individual and society that extend beyond FL/D, including medication costs, health care visits, and opportunity costs of lifelong treatment; and (3) psychosocial and stress burden of being labeled as diseased and the consequence for overall well-being. Adopting this broader definition of morbidity suggests that increases in longevity have been possibly accompanied by an expansion of morbidity, in contrast to Fries’ original hypothesis that morbidity onset (based on only FL/D) would be delayed to a greater extent than increases in survival. There is an urgent need for better data and more research to document morbidity onset and its link with increases in longevity and assess the important question on whether populations while living longer are also healthier

    Two secure non-symmetric role Key-Agreement protocols

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    Recently, some two-party Authenticated Key Agreement protocols over elliptic curve based algebraic groups, in the context of Identity-Based cryptography have been proposed. The main contribution of this category of protocols is to reduce the complexity of performing algebraic operations through eliminating the need to using Bilinear Pairings. In this paper, we proposed two novel Identity-Based Authenticated Key Agreement protocols over non-symmetric role participants without using Bilinear Pairings. The results show that our proposed schemes beside of supporting security requirements of Key Agreement protocols, require a subset of operations with low complexity in compare with related protocols in this scientific area

    The Behavior of Treated Metal Curvature Cup: Improving Friction in Hard on Hard Sliding Contact

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    AbstractThis research investigated the tribology on the metal curvature surface in lubricated of palm olein to determine pits capability friction in hard on hard sliding contact. The study was performed using a four-ball tribotester with holder cup modified and digital microscope. The sliding friction between untreated and treated curve cup were evaluated. The experiment was conducted of constant parameters as speed; load and time under the American Society for Testing and Materials (ASTM), number D 4172. To evaluate lubricant ability all results of this research were compared to findings regarding mineral oil. For qualitative analysis worn wear on the curvature cup without applying lubricant to the sample. The results showed that, the measured friction was low significantly influenced by the treated curvature surface embedded with pits and palm olein as potential anti-friction bio-lubricant

    Mediation Analysis Using the Hierarchical Multiple Regression Technique: A Study of the Mediating Roles of World-Class Performance in Operations

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    The changing environment in an organization is forcing the organization to find a plan of integrated management framework and adequate performance measurement. Failure to plan basically means planning failure for the business. Finding the critical factors of quality management practices (QMP), themediating roles of the contextual factors of world-class performance in operations (i.e., world-class company practices or WCC, operational excellence practices or OE, company nonfinancial performance or CNFP), and the company financial performance would enable the company to facilitate the sustainability of TQM implementation model.This empirical study aims to assess how TQM—a holistic management philosophy initially developed by W. Edward Deming, which integrates improvement strategy, management practices, and organizational performance—is specifically implemented in the oil and gas companies operating in Indonesia. Relevant literature on the TQM, the world-class performance in operations (world-class company and operational performance), the company performance (financial and non-financial performances), and the amendments of the Law of the Republic of Indonesia concerning the oil and gas industry, and related research on how the oil and gas industry in Indonesia develops sustainable competitive advantage and sustainable development programs are reviewed in details in our study. The findings from data analysis provide evidence that there is a strong positive relationship between the critical factors of quality management practices and the company financial performance mediated by the three mediating variables, i.e., world-class company practices, operational excellence practices, and company non-financial performance

    Studi Keandalan Geolistrik Dalam Identifikasi Kebocoran Embung: Studi Kasus Embung Wolo, Sulawesi Tenggara

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    Small dams are vital for supporting water resource conservation. The reservoir stores water from several water sources, especially in the rainy season, so that it remains available in the dry season. Some reservoir infrastructures were built using earthen fill materials located around it. This condition is very vulnerable to disasters, ranging from seepage to collapse. It is important to evaluate the safety of all potential dangers to minimize the risk of disasters. One method that can be used is the geoelectric method, which allows us to analyze the resistivity properties of the soil, but the reliability of this method needs to be further evaluated. This research aims to determine the reliability of geoelectric in identifying potential leaks in reservoirs. Geoelectric measurements were carried out at Wolo Small Dam using the Wenner-Schlumberger configuration with 32 electrodes at 2.5 m. Data collection was carried out at the top of the small dam so that it could provide the condition of the soil layer of the embankment material in the longitudinal direction. Validate the measurement using the results of previous research. The results of the analysis show that there are differences in lithology in the body of the reservoir, which indicates differences in the quality of work during construction. The interface between these two surfaces can lead to leaks. Apart from that, the analysis results also show the potential for piping in the reservoir. The location of the potential piping area is not far from the results obtained in previous research at the same location. This shows that geoelectric is quite capable of being a tool that can be used to identify leaks in reservoirs or other water structures. Of course, the combination of geoelectric and other soil testing will provide better results in anticipating disasters caused by small dam leak
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