Islamic University of Sultan Agung
Semarang, Indonesia
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Waluyo Poetro B.S.,Islamic University of Sultan Agung
IOP Conference Series: Materials Science and Engineering | Year: 2017

Nowadays information technology requires stronger cryptographic algorithms. Camellia algorithm is also known for its suitability in terms of the implementation of both software and hardware as well as a high level of safety. The digital image is an image f (x, y) which having the spatial coordinates, and brightness levels are discrete. Unlike text messages, the image data has special features such as high redundancy and a high correlation between pixels. This research conducted a cryptographic process of the digital image using the Camellia algorithm. Comparisons were made on three digital image format .bmp, .jpg, .png with 128 bits key block Camellia algorithm. Results shows that Camellia cryptographic algorithms in digital image can successfully produce encrypted images. In addition, the same algorithm can also reproduce the image when decryption process. © Published under licence by IOP Publishing Ltd.

Adi H.P.,Islamic University of Sultan Agung
AIP Conference Proceedings | Year: 2017

Labors skills is an important part of construction projects implementation. Suitability between the skills possessed by labors with the skills needed by user is required to increase employment opportunities. Malaysia is a country that using construction labors from Indonesia. This study aims to get the kind of technical skills required by users of Indonesian constructian labors in Malaysia and also the importance level of technical skills. Data collecting in this research was conducted through interviews and questionnaires on contractors in Malaysia. The next stage was determine the importance level of technical skills in work field of carpenter, bricklayer, plumber and painters. The importance level of technical skills analyzed using the Relative Importance Index (RII). The results showed that mastering the operation of both instruments either manually or electrically is the most importance in the technical skills. Therefore, an understanding of the types of equipment for work field and the manner of operation is need to had by Indonesian construction labors who will work in Malaysia. © 2017 Author(s).

Fachrunnisa O.,Islamic University of Sultan Agung
International Journal of Networking and Virtual Organisations | Year: 2014

The success of any interaction through a virtual medium can be determined by the continuity of service delivery. The promptness and competence of service, delivered as promised or agreed are indicators used to measure the success of service delivery. To ensure successful service delivery, we designed a proactive continuous performance monitoring and incentive mechanism. The delivery of service is checked at every intermediate point, so that the progress of the delivery can be monitored easily. With this monitoring design, performance discrepancies can be identified and resolved quickly, thereby preventing the escalation of a problem. Moreover, the incentive mechanism is designed to support continuous performance monitoring. It is proposed that the incentive be given at any intermediate checkpoint instead of at the end of the interaction. We built a prototype and conducted simulations under a variety of conditions. The experiment results show that our proposed framework is effective in facilitating successful service delivery. Copyright © 2014 Inderscience Enterprises Ltd.

Antonius,Islamic University of Sultan Agung | Imran I.,Bandung Institute of Technology
ITB Journal of Engineering Science | Year: 2012

An experimental study of 23 low-, medium- and high-strength concrete columns is presented in this paper. Square-confined concrete columns without longitudinal reinforcement were designed, and tested under concentric axial compression. The columns were made of concrete with a compressive strength ranging between 30 MPa and 70 MPa. The test parameters in the study are concrete compressive strengths and confining steel properties, i.e. spacing, volumetric ratios and configurations. The effects of these parameters on the strength and ductility of square-confined concrete were evaluated. Of the specimens tested in this study, the columns made with higher-strength concrete produced less strength enhancement and ductility than those with lower-strength concrete. The steel configurations were found to have an important role in governing the strength and ductility of the confined high-strength concrete. Moreover, several models of strength enhancement for confined concrete available in the literature turned out to be quite accurate in predicting the experimental results. © 2012 Published by LPPM ITB.

Rusbintardjo G.,Islamic University of Sultan Agung | Hainin M.R.,University of Technology Malaysia | Yusoff N.I.M.,National University of Malaysia
Construction and Building Materials | Year: 2013

This study was conducted to investigate the suitability of using oil palm fruit ash (OPFA) as a bitumen modifier. The OPFA was used to fulfil all bitumen modification requirements, as well as to take advantage of a waste by-product of the palm oil mill industry which could help to reduce environmental pollution. Twenty-four OPFA-modified bitumens (OPFA-MBs) were produced by the laboratory mixing of normal bitumen (80/100) from two sources with Fine and Coarse OPFAs of six different contents. This process was conducted at a mixing temperature of 160 C, a mixing time of 60 min and a mixing stirring speed of 800 rpm. The consistency and rheological characteristics of the OPFA-MBs were analysed by means of conventional as well as dynamic mechanical analysis using dynamic shear rheometer (DSR), bending beam rheometer (BBR) and direct tension test (DTT). The results of the investigation indicate that binder compounded with OPFA becomes less susceptible to temperature, improve resistance to rutting at 70 C, fatigue cracking at 20 C, and thermal cracking at -17 C of the surface pavement temperature compared to the unmodified bitumen. The OPFA-MB can be categorised as a binder with penetration grade of 60/70 or as PG 70-16 in the performance based system. Finally, it can be deduced that it is feasible to use OPFA as a modifier of bitumen.© 2013 Elsevier Ltd. All rights reserved.

Antonius,Islamic University of Sultan Agung
International Journal of Technology | Year: 2015

This paper presents the results of an experimental study of the behavior of high-strength steel fiber-concrete confined by hoops with round cross-sections subjected to concentric loadings. Behavior strength and energy absorption capability of confined fibrous concrete was the main focus of this study. Fibrous concrete test specimens were made by varying concrete's compressive strength and characteristics of hoops reinforcement (i.e., volumetric ratio and spacing). All specimens used longitudinal reinforcement with the same ratio. Experimental results showed that the strength enhancement of confined concrete reinforced with steel fiber is strongly influenced by the characteristics of the installed confining reinforcement. In this paper, the confinement models by researchers were evaluated and compared with the experimental results. The comparison between existing confinement models and experimental results were significantly different, especially in the post-peak behavior. Obtaining accurate characteristic predictions of high-grade confined fibrous concrete is necessary prior to modification of existing confinement models. © IJTech 2015.

Antonius,Islamic University of Sultan Agung
Asian Journal of Civil Engineering | Year: 2014

This paper presents on an experimental study of confined high-strength concrete columns tested under axial compression. The main objective of the research is to know the performance of spirals and hoops with medium strength (400 MPa < fy < 600 MPa) in their contribution on the behaviour of confined high-strength concrete columns. The parameters of the study were concrete strengths, confining steel characteristics i.e: type of confinement (spirals and hoops), yield strength, spacing and volumetric ratio. From the experimental results it was found that the strength enhancement and ductility of confined concrete will decrease with if both of concrete strength and spacing of spirals or hoops increase, and the strain in the test also showed that the release of a cover of concrete core occurs prematurely. Other results shows that satisfactory of circular hoops as confinement steel behaved as good as the spiral reinforcement. The spiral reinforcement provision adopted in the Indonesian Concrete Standard 2002 (SNI 03-2847-2002) is quite reliable when applied in the design of confining steel with medium strength of high-strength concrete columns, therefore it is proposed that the upper limit provision of yield strength of confining steel warrant to be modified.

Fachrunnisa O.,Curtin University Australia | Fachrunnisa O.,Islamic University of Sultan Agung | Hussain F.K.,Curtin University Australia
IEEE Transactions on Industrial Electronics | Year: 2013

Trust is widely considered to be essential for the smooth functioning of digital ecosystems. However, trust by its very nature, and due to the virtual connection between entities, is extremely fragile. Trust has a life cycle which is composed of building, maintaining, and declining. Given the fragility of trust in virtual environments, it is challenging to work out how to maintain the level of trust (specifically positive trust) between two interacting parties. Once positive trust has been established in the trust building phase, a methodological framework is needed to maintain the existing trust level, so that the relationship may be sustained in the future. In this paper, we present a methodology for maintaining trust in industrial digital ecosystems. The methodology proposes the use of a third party agent, an iterative negotiation process, proactive performance monitoring, and intelligence metrics recalibration of the trust level. In a trust-based relationship, trust can be regarded as having been maintained if the final trust is greater than or equal to initial trust. We demonstrate the validity of the methodology by engineering a prototype setup and running simulations under various operational conditions. © 2012 IEEE.

Background: Treatment with buceng combination of Eurycoma longifolia Jack and Pimpinella alpine Molk has been proven to increase testosterone level, decrease apoptosis and caspase3 expression. Bcl2 is an antiapoptotic protein found in cytoplasm which inhibits cells apoptosis. This study was aimed to investigate the effect of buceng on Bcl2 expression on penile and prostate tissues of the rats. Methods: In this experimental study, 24 male Sprague Dawley rats of 90 days old, weighing ± 300 grams, were randomly assigned into four groups. Group A, normal rats. Group B, castrated rats and treated with buceng 100 mg/day, per oral (Cast-Bcg); Group C, castrated rats and treated with 2 ml of water as placebo against buceng (Cast-Plac). Group D, castrated rats, treated with mesterolone 6.75 mg/day, per oral, as exogenous testosterone (Cast-Mest). All rats were treated for 30 days. Manova test was used to analyze the different expression of Bcl2 among groups with significance level at p = 0.05. Results: Castration was associated with significant decrease of Bcl2 expression in the penile and prostate tissues (53.0 and 50.9%, respectively) compared to normal rats (82.6 and 84.2%, respectively, p < 0.001). Treatment with mesterolone reversed Bcl2 expression (77.1 and 78.1%) to a near normal level. The same level of Bcl2 expression was also observed with buceng treatment (73.8 and 78.2%). Conclusion: The treatment with buceng could enhance Bcl2 expression in penile and prostate tissues, comparable to normal rats and mesterolone treated rats. © 2015 Author.

Antonius,Islamic University of Sultan Agung
Procedia Engineering | Year: 2014

It is general knowledge that the design of earthquake-resistant structures for high-strength concrete columns requires confiningreinforcement with a relatively high volumetric ratio to ensure the ductility of the structure. This implies that the mechanical behavior of high-strength concrete differs significantly from the behavior of normal-strength concrete. However, the provisions on the minimum volumetric ratio of confining-reinforcement contained in the Indonesian Concrete Code (SNI 2847-2013) is essentially derived from the test results for normal-strength concrete. This paper studies the confining-reinforcement provisions used in several standards, i.e., SNI 2847-2013, ACI-2011, NZS-2006 and CSA-2004, to determine the ductility of the concrete columns. The case study is based on the analysis of the cross-section of high-strength concrete columns, the parameters that affect the strength, and by evaluating the value of the column's cross -section curvature ductility. The study results showed that the equation for confining-reinforcement adopted in the SNI 2847-2013 is very conservative compared to other codes when applied to low axial load levels (?0.2) , but is relatively less conservative if the axial load level is greater than 0.3. © 2014 The Authors. Published by Elsevier Ltd.

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