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Serpong, Indonesia

Rahmawan Y.,University of Pennsylvania | Rahmawan Y.,Surya University | Chen C.-M.,University of Pennsylvania | Yang S.,University of Pennsylvania
Soft Matter | Year: 2014

Surface wrinkles driven by elastic instabilities have attracted significant interest in the field of materials science and engineering. They are simple and readily fabricated with various patterns of tunable size, morphology and surface topography from a wide range of material systems. Recently, they have been investigated as a new type of dry adhesives. In this review, after a brief introduction of different methods to prepare wrinkle surfaces, we focus on the investigation of dry adhesion mechanisms in different material systems. By exploiting wrinkle dimension, morphology, modulus, curvature, and different contacting surfaces (flat, hemispherical, spherical) and their complementarity, we show adhesion enhancement, reduction and selectivity. By comparing experimental results with theoretical predictions, we aim to provide a guideline to design and engineer wrinkle-based dry adhesives. Several examples of applications of engineered wrinkles are also demonstrated, including pick, release and transfer of nanoparticles and bulk materials, and gecko-like hybrid adhesives. The review is concluded with perspectives on the wrinkling technology for smart dry adhesives. This journal is © the Partner Organisations 2014.

Susanto R.D.,University of Maryland University College | Susanto R.D.,Surya University | Song Y.T.,Jet Propulsion Laboratory
Journal of Geophysical Research C: Oceans | Year: 2015

The Indonesian throughflow (ITF) from the Pacific to the Indian Ocean plays an important role in global ocean circulation and climate. Yet, continuous ITF measurement is difficult and expensive. The longest time series of in situ measurements of the ITF to date were taken in the Makassar Strait, the main pathway of the ITF. Here we have demonstrated a plausible approach to derive the ITF transport proxy using satellite altimetry sea surface height (SSH), gravimetry ocean bottom pressure (OBP) data, in situ measurements from the Makassar Strait from 1996 to 1998 and 2004 to 2011, and a theoretical formulation. We first identified the optimal locations of the correlation between the observed ITF transport through the Makassar Strait and the pressure gradients, represented by the SSH and OBP differences between the Pacific and Indian Oceans at a 1° × 1° horizontal resolution. The optimal locations were found centered at 162°E and 11°N in the Pacific Ocean and 80°E and 0° in the Indian Ocean, then were used in the theoretical formulation to estimate the throughflow. The proxy time series follow the observation time series quite well, with the 1993-2011 mean proxy transport of 11.6 ± 3.2 Sv southward, varying from 5.6 Sv during the strong 1997 El Niño to 16.9 Sv during the 2007 La Nina period, which are consistent with previous estimates. The observed Makassar mean transport is 13.0 ± 3.8 Sv southward over 2004-2011, while the SSH proxy (for the same period) gives an ITF mean transport of 13.9 ± 4.1 Sv and the SSH + OBP proxy (for 2004-2010) is 15.8 ± 3.2 Sv. © 2015. American Geophysical Union. All Rights Reserved.

Shokri Rad M.,University of Technology Malaysia | Prawoto Y.,Surya University | Ahmad Z.,University of Technology Malaysia
Mechanics of Materials | Year: 2014

One of the methods in understanding the real microstructure of auxetic material is by separating it into several simplified structures that have distinct mechanisms. Among those simplified structures are chiral and re-entrant structures. This paper adapts a 2D re-entrant structure for a 3D auxetic structure. A re-entrant structure is chosen due to its fundamental characteristics underlying the main characteristics of auxetic materials. The energy methods of solid mechanics along with numerical methods are used to study the fundamental concept of auxetic materials. Understanding the characteristics of the re-entrant structure will lead to the better comprehension of other structures of auxetic materials, which will eventually contribute to the advance of research in this new class of materials. © 2014 Elsevier Ltd. All rights reserved.

Tham H.-W.,University of Selangor | Balasubramaniam V.R.M.T.,University of Selangor | Ario Tejo B.,Surya University | Ahmad H.,Universiti Sains Malaysia | Syed Hassan S.,University of Selangor
Viruses | Year: 2014

Aedes aegypti is a principal vector responsible for the transmission of dengue viruses (DENV). To date, vector control remains the key option for dengue disease management. To develop new vector control strategies, a more comprehensive understanding of the biological interactions between DENV and Ae. aegypti is required. In this study, a cDNA library derived from the midgut of female adult Ae. aegypti was used in yeast two-hybrid (Y2H) screenings against DENV2 envelope (E) protein. Among the many interacting proteins identified, carboxypeptidase B1 (CPB1) was selected, and its biological interaction with E protein in Ae. aegypti primary midgut cells was further validated. Our double immunofluorescent assay showed that CPB1-E interaction occurred in the endoplasmic reticulum (ER) of the Ae. aegypti primary midgut cells. Overexpression of CPB1 in mosquito cells resulted in intracellular DENV2 genomic RNA or virus particle accumulation, with a lower amount of virus release. Therefore, we postulated that in Ae. aegypti midgut cells, CPB1 binds to the E protein deposited on the ER intraluminal membranes and inhibits DENV2 RNA encapsulation, thus inhibiting budding from the ER, and may interfere with immature virus transportation to the trans-Golgi network. © 2014 by the authors; licensee MDPI, Basel, Switzerland.

Warnars S.,Surya University
2014 2nd International Conference on Information and Communication Technology, ICoICT 2014 | Year: 2014

This paper is extended version from previous paper which proposed AOI-HEP as novel data mining technique. This paper will explain how AOI-HEP mining technique can be used to mine frequent pattern. AOI-HEP is influenced by Attribute Oriented Induction (AOI) and Emerging Pattern (EP) mining techniques by applying AOI characteristic rule algorithm and improvement EP growth rate. The experiment used adult dataset from UCI machine learning repository with 48842 instances, run in 3 seconds and the instances were discriminated between government and non government concepts based on learning on workclass attribute. AOI-HEP mining interest for frequent pattern will be influenced by learning on their chosen attribute. The experiments showed that adult dataset which learn on workclass attribute had AOI-HEP mining interest for frequent pattern and there are four frequent patterns which have strong discrimination rule. Meanwhile, extended experiments upon adult dataset which learn on marital-status attribute showed there is no AOI-HEP mining interest for frequent pattern. © 2014 IEEE.

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