A malaria model with controls on mass treatment and insecticide

Fatmawati^a ,

Tasman, H.^b 

^a  Department of Mathematics, Faculty of Science and Technology, Universitas Airlangga Kampus C Unair, Jl. Mulyorejo Surabaya 60115, Indonesia
^b  Department of Mathematics, Faculty of Mathematics and Natural Science, Universitas Indonesia Kampus UI Depok, Depok 16424, Indonesia 

Abstract

In this paper we derive a mathematical model for malaria transmis-sion in population. We use controls on mass treatment and insecticide to reduce the number of infected hosts and infected vectors. The model considers human, larvae and mosquito populations. The host popula- tion is assumed constant, but the larvae and vector populations vary. First, we investigated the existence and stability of equilibria of the model without control based on the basic reproduction ratio. Then, the Pontryagins maximum principle is used to characterize the optimal control. The optimality system is derived and solved numerically for several scenarios. © 2013 Fatmawati and Hengki Tasman.

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http://www.m-hikari.com/ams/ams-2013/ams-65-68-2013/33180.html

Concentrations of Lead, Cadmium, and Mercury in Halfbeaks (Hyporhampus affinis) from the East Java Coast, Indonesia and Human Health Hazard

Asmysari, A.S.,

Irawan, B.,

Soegianto, A. 

Department of Biology, Faculty of Sciences and Technology, Airlangga University, Kampus C Unair, Jl. Mulyorejo, Surabaya, Indonesia 

Abstract

The objectives of this study were to measure the levels of lead, cadmium, and mercury in the muscle tissues of halfbeaks (Hyporhampus affinis) captured at five stations along the East Java coast, Indonesia. This fish is one of the important species and consumed by local people as a cheap source of protein. We evaluated the hazard level posed by the metals in relation to the maximum residual limit for human consumption and to estimate the weekly intake and compare it with the provisional tolerable weekly intake (PTWI). The Pb, Cd, and Hg concentrations in fish at all stations ranged from 0.006 to 0.023 mg/kg, 0.007 to 0.024 mg/kg, and 0.047 to 0.055 mg/kg wet weight, respectively. All samples of halfbeaks collected from this area appear to be safe for human consumption because their metals' levels are below the permissible limit for human consumption and the maximum weekly intakes are below the recommended values of PTWI. © 2013 Copyright Taylor and Francis Group, LLC.

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http://www.tandfonline.com/doi/abs/10.1080/10807039.2012.729140

Reduced-order model based on H∞-balancing for infinite-dimensional systems

Fatmawati^a ,

Saragih, R.^b ,

Soeharyadi, Y.^b 

^a  Department of Mathematics, Faculty of Science and Technology, Universitas Airlangga, Kampus C Unair, Jl. Mulyorejo, Surabaya 60115, Indonesia
^b  Department of Mathematics, Faculty of Mathematics and Natural Science, Institut Teknologi Bandung, Jl. Ganesa 10, Bandung, Indonesia 

Abstract

This paper presents a model reduction for unstable infinite dimen-sional system (A;B;C) using H∞-balancing. To construct H∞-balanced realization, we find a Lyapunov-balanced realizationof a normalized left-coprime factorization (NLCF) of the scaled system (A; βB;C). Next, we apply the new coordinate transformation to obtain yet another re-alization of NLCF system. This result is then translated to have the new scaled system (A^t; βB^t;C^t) whichsimilar with (A; βB;C). Fur-thermore, it can be verified that the solutions of a control and ffilter H∞-Riccati operator equations of the system (A^t;B^t;C^t) are equal and diagonal. This implies that the system (A^t;B^t;C^t) is H∞-balanced re-alization of the system (A;B;C). Based on the small H∞-characteristic values, the state variables of the system (A^t;B^t;C^t) is truncated, to yield a reduced-order model of the system (A;B;C). To demonstrate the effectiveness of the proposed method, numerical simulations are ap-plied to Euler-Bernoulli beam equation.

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https://www.google.co.id/url?sa=t&rct=j&q=&esrc=s&source=web&cd=1&cad=rja&uact=8&ved=0ahUKEwiTxqaK1LbPAhXJnJQKHSpYBPgQFggfMAA&url=http%3A%2F%2Fwww.m-hikari.com%2Fams%2Fams-2013%2Fams-9-12-2013%2FfatmawatiAMS9-12-2013.pdf&usg=AFQjCNHYP72V8aPb-FUqbrhmxXDJSlqApQ&sig2=PNi56VcpQrnvenWPxPcOaQ

Detection of stain formation on teeth by oral antiseptic solution using fiber optic displacement sensor

Rahman, H.A.^abd,

Rahim, H.R.A.^ef,

Harun, S.W.^ab ,

Yasin, M.^bc,

Apsari, R.^c,

Ahmad, H.^b,

Wan Abas, W.A.B.^e

^a  Department of Electrical Engineering, Faculty of Engineering, University of Malaya, 50603 KualaLumpur,Malaysia
^b  Department of Physics, Photonics Research Centre, University of Malaya, 50603 Kuala Lumpur, Malaysia ^c  

Abstract

The application of a simple intensity modulated fiber optic displacement sensor for the detection of stain formation on human teeth is demonstrated. The proposed sensor uses a concentric type bundled plastic optical fiber (POF) as a probe in conjunction with the surfaces of five human teeth as the reflecting targets. Prior to the experiment, the stains were produced extrinsically by soaking the teeth in different concentrations of oral antiseptic solution containing hexetidine. The concentration of the oral antiseptic solution is measured in volume%. For a concentration change from 0% to 80%, the peak voltage decreases exponentially from 1.15 mV to 0.41 mV with a measured resolution of 0.48% and 1.75% for concentration ranges of 0-40% and 40-80%, respectively. The correlation between the detector output and variation in the color of human tooth surface has successfully been examined. Simple in design and low in cost, this sensor can detect color changes due to hexetidine-induced stain on a tooth surface in a fast and convenient way. Thus, this sensor will be very promising in esthetic dentistry, dental color matching techniques, chemical and biomedical applications. © 2012 Elsevier Ltd.

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http://www.sciencedirect.com/science/article/pii/S0030399212002952

Image reconstruction in ring array ultrasound tomography by means of enhancing the Sinogram

Ain, K.^ac ,

Kurniadi, D.^a,

Trisnobudi, A.^a,

Santoso, O.^b

^a  Faculty of Industrial Technology, Indonesia
^b  Faculty School of Electrical Engineering and Informatics, Institut Teknologi Bandung, Bandung, Indonesia ^c  

Abstract

The Ring Array Ultrasound Tomography is the system which has been used for breast cancer detection. The system is potentially developed due to unmovable mechanically, safe and obtainable high resolution image. The study means to reconstruct ring array ultrasound tomography by reposition and spline-interpolation data into parallel beam Sinogram. The study was conducted with numerical and experimental object by 16 and 32 transducer positions to obtain 31×31 pixels of images. Sinogram was repaired by an RMSD method and reconstructed by the SCFBP method. The results indicate that the methods of Sinogram enhancement can only improve the image of 0.02%. The study showed that 16 transducers had produced a blur image and been dissimilar to the object, but 32 transducers could generate a good image but it is still worse than parallel beam. © 2013 by IJIR (CESER Publications).

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http://www.ceser.in/ceserp/index.php/iji/article/view/2863