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Czechowski N.,Nicolaus Copernicus University | Nyga P.,Military University of Technology | Schmidt M.K.,Nicolaus Copernicus University | Brotosudarmo T.H.P.,Ma Chung University | And 3 more authors.
Plasmonics | Year: 2012

We report on experimental and theoretical studies of plasmon-induced effects in a hybrid nanostructure composed of light-harvesting complexes and metallic nanoparticles in the form of semicontinuous silver film. The results of continuous-wave and time-resolved spectroscopy indicate that absorption of the light-harvesting complexes is strongly enhanced upon coupling with the metallic film spaced by 25 nm of a dielectric silica layer. This conclusion is corroborated by modeling, which confirms the morphology of the silver island film. © 2011 The Author(s).


Swastika W.,Ma Chung University | Haneishi H.,Chiba University
Telkomnika | Year: 2012

The use of circulant matrix as the sensing matrix in compressed sensing (CS) scheme has recently been proposed to overcome the limitation of random or partial Fourier matrices. Aside from reducing computational complexity, the use of circulant matrix for magnetic resonance (MR) image offers the feasibility in hardware implementations. This paper presents the simulation of compressed sensing for thoracic MR imaging with circulant matrix as the sensing matrix. The comparisons of reconstruction of three different type MR images using circulant matrix are investigated in term of number of samples, number of iteration and signal to noise ratio (SNR). The simulation results showed that circulant matrix works efficiently for encoding the MR image of respiratory organ, especially for smooth and sparse image in spatial domain. © 2012 Universitas Ahmad Dahlan.


Bujak L.,Nicolaus Copernicus University | Czechowski N.,Nicolaus Copernicus University | Piatkowski D.,Nicolaus Copernicus University | Litvin R.,Nicolaus Copernicus University | And 5 more authors.
Applied Physics Letters | Year: 2011

The influence of plasmon excitations in spherical gold nanoparticles on the optical properties of a light-harvesting complex 2 (LH2) from the purple bacteria Rhodopseudomonas palustris has been studied. Systematic analysis is facilitated by controlling the thickness of a silica layer between Au nanoparticles and LH2 complexes. Fluorescence of LH2 complexes features substantial increase when these complexes are separated by 12 nm from the gold nanoparticles. At shorter distances, non-radiative quenching leads to a decrease of fluorescence emission. The enhancement of fluorescence originates predominantly from an increase of absorption of pigments comprising the LH2 complex. © 2011 American Institute of Physics.


Buczynska D.,Nicolaus Copernicus University | Bujak L.,Nicolaus Copernicus University | Loi M.A.,Zernike Institute for Advanced Materials | Brotosudarmo T.H.P.,Ma Chung University | And 3 more authors.
Applied Physics Letters | Year: 2012

Energy transfer from a conjugated polymer blend (poly(9,9-dioctylfluorenyl- 2,7-diyl):poly (2-methoxy-5-(2-ethylhexyloxy)-1, 4-phenylenevinylene) to a light-harvesting complex 2 from purple bacteria has been demonstrated using time-resolved fluorescence spectroscopy. For our hybrid nanostructure, we observe a 30 reduction of the fluorescence lifetime of the polymer emission as compared to the pure polymer layer. This result is an important step towards integrating naturally evolved biomolecules with synthetic materials into biohybrid organic electronic systems. © 2012 American Institute of Physics.


Widodo R.B.,Kyushu Institute of Technology | Widodo R.B.,Ma Chung University | Wada C.,Kyushu Institute of Technology
Journal of Sensors | Year: 2016

Attitude estimation is often inaccurate during highly dynamic motion due to the external acceleration. This paper proposes extended Kalman filter-based attitude estimation using a new algorithm to overcome the external acceleration. This algorithm is based on an external acceleration compensation model to be used as a modifying parameter in adjusting the measurement noise covariance matrix of the extended Kalman filter. The experiment was conducted to verify the estimation accuracy, that is, one-axis and multiple axes sensor movement. Five approaches were used to test the estimation of the attitude: (1) the KF-based model without compensating for external acceleration, (2) the proposed KF-based model which employs the external acceleration compensation model, (3) the two-step KF using weighted-based switching approach, (4) the KF-based model which uses the threshold-based approach, and (5) the KF-based model which uses the threshold-based approach combined with a softened part approach. The proposed algorithm showed high effectiveness during the one-axis test. When the testing conditions employed multiple axes, the estimation accuracy increased using the proposed approach and exhibited external acceleration rejection at the right timing. The proposed algorithm has fewer parameters that need to be set at the expense of the sharpness of signal edge transition. © 2016 Romy Budhi Widodo and Chikamune Wada.


Brotosudarmo T.H.P.,University of Glasgow | Brotosudarmo T.H.P.,Ma Chung University | Collins A.M.,Washington University in St. Louis | Collins A.M.,Sandia National Laboratories | And 5 more authors.
Biochemical Journal | Year: 2011

The differing composition of LH2 (peripheral light-harvesting) complexes present in Rhodopseudomonas palustris 2.1.6 have been investigated when cells are grown under progressively decreasing light intensity. Detailed analysis of their absorption spectra reveals that there must be more than two types of LH2 complexes present. Purified HL (high-light) and LL (low-light) LH2 complexes have mixed apoprotein compositions. The HL complexes contain PucAB a and PucAB b apoproteins. The LL complexes contain PucAB a, PucAB dand PucB b-only apoproteins. This mixed apoprotein composition can explain their resonance Raman spectra. Crystallographic studies and molecular sieve chromatography suggest that both the HL and the LL complexes are nonameric. Furthermore, the electron-density maps do not support the existence of an additional Bchl (bacteriochlorophyll) molecule; rather the density is attributed to the N-termini of the α-polypeptide. © The Authors Journal compilation © 2011 Biochemical Society.


Ekawati Y.,Ma Chung University | Bazarado M.,Ma Chung University
ARPN Journal of Engineering and Applied Sciences | Year: 2016

Carrots are healthy vegetables but this agricultural products have low value when they are sold as a raw commodity. To become value-added agricultural products, the value of raw carrots have to be increased through the addition of ingredients or processes that make them more attractive to the buyer. Increasing the added value of the carrots requires the development of food products that considering the voice of the customer. The aim of the research was to design food products based on carrots desired by the customer. The development of product design used Quality Function Deployment (QFD) method especially the product design phase. Candied carrot and carrot syrup were the products had been found in the previous research conducted to find the carrot based products most wanted by the customers. The research had developed the House of Quality matrix, whose technical requirements were used to develop product design matrix in this research. The product design of the two products were developed using QFD with two different developments, one for the product and one for the package. All of the critical parts resulted in this research, although each of them has different priorities, were important to develop the new products. © 2006-2016 Asian Research Publishing Network (ARPN).


Brotosudarmo T.H.P.,Ma Chung University | Prihastyanti M.N.U.,Ma Chung University | Gardiner A.T.,University of Glasgow | Carey A.-M.,University of Glasgow | Cogdell R.J.,University of Glasgow
Energy Procedia | Year: 2014

The overall process of photosynthesis can be deconstructed into four distinct stages, each of which can be mimicked as a first step towards developing robust, integrated, supra-molecular systems or devices capable of using solar energy to produce a reduced product, fuel. This process is necessary because natural photosynthesis is rather inefficient. In this short review we outline the steps that would be required to produce systems capable of using solar energy to make fuels more efficiently. It is emphasised that these aims will require an extended multi-disciplinary effort that will undoubtedly involve close collaboration between academic and industrial scientists. © 2014 The Authors. Published by Elsevier Ltd.


Oktariani F.,Bandung Institute of Technology | Okazaki A.T.,Hokkai Gakuen University | Kunjaya C.,Bandung Institute of Technology | Kunjaya C.,Ma Chung University | Aprilia,Bandung Institute of Technology
Monthly Notices of the Royal Astronomical Society | Year: 2016

We study the effect of density distribution evolution on the global one-armed oscillation modes in low-viscosity discs around isolated and binary Be stars. Observations show that some Be stars exhibit evidence of formation and dissipation of the equatorial disc. In this paper, we first calculate the density evolution in discs around isolated Be stars. To model the formation stage of the disc, we inject mass at a radius just outside the star at a constant rate for 30-50 yr. As the disc develops, the density distribution approaches the form of the steady disc solution. Then, we turn-off the mass injection to model the disc dissipation stage. The innermost part of the disc starts accretion, and a gap forms between the star and the disc. Next, we calculate the one-armed modes at several epochs. We neglect the effect of viscosity because the time-scale of oscillations is much shorter than the disc evolution time-scale for low viscosity. In the disc formation stage, the eigenfrequency increases with time towards the value for the steady state disc. On the other hand, one-armed eigenmodes in dissipating Be discs have significantly higher eigenfrequencies and narrower propagation regions. Observationally, such a change of mode characteristics can be taken as an evidence for gap opening around the star. In binary Be stars, the characteristics of the disc evolution and the eigenmodes are qualitatively the same as in isolated Be stars, but quantitatively, they have shorter evolution time-scales and higher eigenfrequencies, which is in agreement with the observed trend. © 2016 The Authors Published by Oxford University Press on behalf of the Royal Astronomical Society.


Prihastyanti M.N.U.,Ma Chung University | Indriatmoko,Ma Chung University | Brotosudarmo T.H.P.,Ma Chung University
Energy Procedia | Year: 2014

Purple photosynthetic light-harvesting (LH2) is attractive complex module for hybrid nanostructures. Bacteriochlorophyll a in LH2 absorb at 320-400 nm, 585 nm and at near-infrared region (B800, B850 bands), while carotenoids absorb at 400-550 nm. Prior for application, LH2 has to be extracted from its native membrane and placed in suitable matrix. This study reports photostability assay of LH2 from Rhodopseudomonas palustris under continuous illumination in its native membrane and in solubilized condition in different detergent buffers. Continual degradation has been observed by the decrease of intensity at λmax, yet can be slowed-down and restrained by addition of glycerol or polyvinyl-alcohol. © 2014 The Authors. Published by Elsevier Ltd.

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