A conducting domain surface boundary applied to hybrid FEM-FDTD Electromagnetic Models

A modified boundary surface between the two domains in the hybrid FEM-FDTD technique is presented. This permits a heterogeneous surface to be imposed, allowing selected parts to be represented as being conducting or non-conducting. This enables a reduced surface size to be used in cases where an antenna is above a conducting plane, as well as facilitating a range of other practical scenarios. Examples presented show stable results and good agreement with published data

Positioning Control of an Antagonistic Pneumatic Muscle Actuated System using Feedforward Compensation with Cascaded Control Scheme

This paper presents a feedforward compensation with cascaded control scheme (FFC) for the positioning control of a vertical antagonistic based pneumatic muscle actuated (PMA) system. Owing to the inherent nonlinearities and time varying parameters exhibited by PMA, conventional fixed controllers unable to demonstrate high positioning performance. Hence, the feedforward compensation with cascaded control scheme is proposed whereby the scheme includes a PID controller coupled with nonlinear control elements. The proposed scheme has a simple control structure in addition to its straightforward design procedures. Though there are nonlinear control elements involved, these elements are derived from the open loop system responses that does not requires any accurate known parameters. Performance of the FFC scheme are then evaluated experimentally and compared to a PID controller with feedforward compensation (FF-PID) in point-to-point motion of different step heights. Overall, the experimental results show that the effectiveness of the proposed FFC scheme in reducing the steady state error to zero in comparison to FF-PID controller for all cases of step heights examined

Interference temperature measurements and spectrum occupancy evaluation in the context of cognitive radio

This paper presents a refined radio spectrum measurement platform specifically designed for spectrum occupancy surveys in the context of Cognitive radio. Cognitive radio permits the opportunistic usage of licensed bands by unlicensed users without causing harmful interference to the licensed user. In this work, a study based on the measurement of the 800 MHz to 2.4 GHz frequency band at two different locations inside Universiti Teknologi Malaysia (UTM), Johor Bahru campus, Malaysia is presented. Two Tektronix RSA306B spectrum analyzer are set up to conduct simultaneous measurements at different locations for a 24 hours period. The analysis conducted in this work is based on the real spectrum data acquired from environment in the experimental set up. Busy and idle channels were identified. The channels subject to adjacent-channel interference were also identified, and the impact of the detection threshold used to detect channel activities was also discussed. The consistency of the observed channel occupation over a range of thresholds and a sudden drop has good characteristics in determining an appropriate threshold needed in order to avoid interference

Ecology of the coastal heath forest flora - a case study from Terengganu, Malaysia

This study was conducted to determine the floral diversity and biomass in a coastal heath forest at Rantau Abang, Terengganu, Malaysia. The plot included contiguously arranged 100 subplots (10 m x 10 m). Results showed that 959 trees of 63 species belonging to 52 genera and 30 families are distributed in this coastal forest. Myrtaceae is the largest family (163 trees) followed by Annonaceae (160 trees) and Lecythidaceae (100 trees). Euphorbiaceae is the most diverse family containing 6 genera and 6 species. Syzygium claviflorum var. claviflorum (15.5%) was the dominant species followed by Polyalthia hypogaea (12.7%) and Barringtonia macrostachya (10.4%). Dipterocarpaceae has a small stocking as compared to the non-dipterocarp families in this forest. This family comprised about 9% of tree density and 6% of tree species diversity. The dominant species from Dipterocarpaceae is Shorea materialis. The total biomass in the forest lies around 249 ton/ha. The largest contribution to the biomass comes from Dipterocarpaceae with 86 ton/ha (34.5%) followed by Myrtaceae 75.3 ton/ha (30.2%). The biomass contribution of Shorea materialis is78.8 ton/ha, followed by Syzygium claviflorum 67.8 ton/ha. The biomass of Champereia griffithii is 0.006 ton/ha

Business intelligence readiness factors for higher education institution

Higher Education Institution (HEI) have embarked on the new style of decision-making with the aim to enhance the speed and reliability of decision-making capabilities. One of the hardest challenges in implementing Business Intelligence (BI) is the organization’s readiness towards adopting and implementing BI systems. Currently, few published studies have examined BI readiness in HEI environment. Seeing this challenge, this study aims to contribute in determining the BI readiness factors in HEI specifically in the deployment strategies. Through inductive attention to BI in HEI environment, three broad factors have been identified: a) Organizational – that concerning on business strategies, process and structure, b) Technology – involves the BI system and knowledge for managing including the sources and c) Social – the culture within organization that may influence decision-making and its processes. This paper also makes recommendations for future research

Proving Termination Starting from the End

We present a novel technique for proving program termination which introduces a new dimension of modularity. Existing techniques use the program to incrementally construct a termination proof. While the proof keeps changing, the program remains the same. Our technique goes a step further. We show how to use the current partial proof to partition the transition relation into those behaviors known to be terminating from the current proof, and those whose status (terminating or not) is not known yet. This partition enables a new and unexplored dimension of incremental reasoning on the program side. In addition, we show that our approach naturally applies to conditional termination which searches for a precondition ensuring termination. We further report on a prototype implementation that advances the state-of-the-art on the grounds of termination and conditional termination.Comment: 16 page

Fate of Chemical Activators in the Aqueous Environment: What Should We Do About IT?

The commonly used activators in chemical activation of activated carbon are very toxic and poisonous to the aquatic environment. Finding trade-off solutions without compromising the quality of activated carbon and jeopardizing the environment have become the subject of considerable interest. This paper is aimed to shed some light on the inevitable release of chemical activators to the aqueous environment, and offers some possible solutions to overcome the emergence of secondary pollution

Complexity Bounds for Ordinal-Based Termination

`What more than its truth do we know if we have a proof of a theorem in a given formal system?' We examine Kreisel's question in the particular context of program termination proofs, with an eye to deriving complexity bounds on program running times. Our main tool for this are length function theorems, which provide complexity bounds on the use of well quasi orders. We illustrate how to prove such theorems in the simple yet until now untreated case of ordinals. We show how to apply this new theorem to derive complexity bounds on programs when they are proven to terminate thanks to a ranking function into some ordinal.Comment: Invited talk at the 8th International Workshop on Reachability Problems (RP 2014, 22-24 September 2014, Oxford

Design of a 3D Printed UWB Antenna for a Low-Cost Wireless Heart and Respiration Rate Monitoring

This paper introduces an ultra-wideband (UWB) horn antenna for a low-cost wireless heart and respiration rate monitoring that is manufactured by a 3D printing technology. The proposed design operates within 3.1-10.6 GHz. The horn antenna is designed within the 15-dB gain which is sufficient to be used in medical system. The horn was designed to calculate the gain in MATLAB using an approximation method and simulated using CST Microwave Studio. The proposed antenna is 4-6 GHz (G-Band) operating. A printed antenna which is supported by WR-187 rectangular waveguide is fabricated using low cost polylactic acid (PLA). The surface is then metalized using copper tape on the inside. The simulation result of reflection coefficient for different conductivity and thickness of coating metal is compared, the developed 3D printed antenna successfully operated within given frequency range of 3-11 GHz which covered the ultra-wideband frequency range