Toward biomaterial-based implantable photonic devices

Humar, Matjaž,Kwok, Sheldon J. J.,Choi, Myunghwan,Yetisen, Ali K.,Cho, Sangyeon,Yun, Seok-Hyun De Gruyter Open 2017 Nanophotonics Vol.6 No.2

<P><B>Abstract</B></P><P>Optical technologies are essential for the rapid and efficient delivery of health care to patients. Efforts have begun to implement these technologies in miniature devices that are implantable in patients for continuous or chronic uses. In this review, we discuss guidelines for biomaterials suitable for use<I>in vivo</I>. Basic optical functions such as focusing, reflection, and diffraction have been realized with biopolymers. Biocompatible optical fibers can deliver sensing or therapeutic-inducing light into tissues and enable optical communications with implanted photonic devices. Wirelessly powered, light-emitting diodes (LEDs) and miniature lasers made of biocompatible materials may offer new approaches in optical sensing and therapy. Advances in biotechnologies, such as optogenetics, enable more sophisticated photonic devices with a high level of integration with neurological or physiological circuits. With further innovations and translational development, implantable photonic devices offer a pathway to improve health monitoring, diagnostics, and light-activated therapies.</P>

Making Inferences About Settlements from Satellite Images Using Glowworm Swarm Optimization

Emre Avuçlu,Abdullah Elen,Humar Kahramanli Örnek 대한전기학회 2020 Journal of Electrical Engineering & Technology Vol.15 No.5

Optimization is the process of choosing the best one among existing possibilities under particular circumstances in a problem. There are various algorithms for optimization problems nowadays. Metaheuristic algorithms are the algorithms giving almost optimum solutions at an acceptable duration for the problems of large dimension. Heuristic optimization algorithms with general aim are evaluated in diff erent groups. Swarm intelligence-based optimization algorithms were developed through examining the behaviors and movements of living fl ocks such as birds, fi sh, cats, and bees. With these algorithms, some estimating processes are carried out successfully in all areas. In this study a new approach was presented with a novel idea, by inspiring from the behavior type of Glowworm Swarm Optimization; and an application estimating the total population, square measurement and electricity quantity that was consumed by the chosen areas in a region was developed. The developed application works as a real-time and animated display. When all calculations are fi nished, the animation ends. Estimates also examined England as an example. The diff erence between the estimated value of the actual population of England is calculated as 1.7%. In the estimates for the values of the surface area of England with an error of 1.4%, the estimated values were very close to the actual values. Some other obtained estimation results are presented in the results section

Seismic performance of concrete moment resisting frame buildings in Canada

Kafrawy, Omar El,Bagchi, Ashutosh,Humar, Jag Techno-Press 2011 Structural Engineering and Mechanics, An Int'l Jou Vol.37 No.2

The seismic provisions of the current edition (2005) of the National Building Code of Canada (NBCC) differ significantly from the earlier edition. The current seismic provisions are based on the uniform hazard spectra corresponding to 2% probability of exceedance in 50 years, as opposed to the seismic hazard level with 10% probablity of exeedance in 50 years used in the earlier edition. Moreover, the current code is presented in an objective-based format where the design is performed based on an acceptable solution. In the light of these changes, an assessment of the expected performance of the buildings designed according to the requirements of the current edition of NBCC would be very useful. In this paper, the seismic performance of a set of six, twelve, and eighteen story buildings of regular geometry and with concrete moment resisting frames, designed for Vancouver western Canada, has been evaluated. Although the effects of non-structural elements are not considered in the design, the non-structural elements connected to the lateral load resisting systems affect the seismic performance of a building. To simulate the non-structural elements, infill panels are included in some frame models. Spectrum compatible artificial ground motion records and scaled actual accelerograms have been used for evaluating the dynamic response. The performance has been evaluated for each building under various levels of seismic hazard with different probabilities of exceedance. From the study it has been observed that, although all the buildings achieved the life-safety performance as assumed in the design provisions of the building code, their performance characteristics are found to be non-uniform.

Seismic performance of concrete moment resisting frame buildings in Canada

Omar El Kafrawy,Ashutosh Bagchi,Jag Humar 국제구조공학회 2011 Structural Engineering and Mechanics, An Int'l Jou Vol.37 No.2

The seismic provisions of the current edition (2005) of the National Building Code of Canada (NBCC) differ significantly from the earlier edition. The current seismic provisions are based on the uniform hazard spectra corresponding to 2% probability of exceedance in 50 years, as opposed to the seismic hazard level with 10% probablity of exeedance in 50 years used in the earlier edition. Moreover, the current code is presented in an objective-based format where the design is performed based on an acceptable solution. In the light of these changes, an assessment of the expected performance of the buildings designed according to the requirements of the current edition of NBCC would be very useful. In this paper, the seismic performance of a set of six, twelve, and eighteen story buildings of regular geometry and with concrete moment resisting frames, designed for Vancouver western Canada, has been evaluated. Although the effects of non-structural elements are not considered in the design, the nonstructural elements connected to the lateral load resisting systems affect the seismic performance of a building. To simulate the non-structural elements, infill panels are included in some frame models. Spectrum compatible artificial ground motion records and scaled actual accelerograms have been used for evaluating the dynamic response. The performance has been evaluated for each building under various of seismic hazard with different probabilities of exceedance. From the study it has been observed that, although all the buildings achieved the life-safety performance as assumed in the design provisions of the building code, their performance characteristics are found to be non-uniform.

Photonic hydrogel sensors

Yetisen, A.K.,Butt, H.,Volpatti, L.R.,Pavlichenko, I.,Humar, M.,Kwok, S.J.J.,Koo, H.,Kim, K.S.,Naydenova, I.,Khademhosseini, A.,Hahn, S.K.,Yun, S.H. Pergamon Press ; Elsevier Science Ltd 2016 BIOTECHNOLOGY ADVANCES Vol.34 No.3

<P>Analyte-sensitive hydrogels that incorporate optical structures have emerged as sensing platforms for point-of-care diagnostics. The optical properties of the hydrogel sensors can be rationally designed and fabricated through self-assembly, microfabrication or laser writing. The advantages of photonic hydrogel sensors over conventional assay formats include label-free, quantitative, reusable, and continuous measurement capability that can be integrated with equipment-free text or image display. This Review explains the operation principles of photonic hydrogel sensors, presents syntheses of stimuli-responsive polymers, and provides an overview of qualitative and quantitative readout technologies. Applications in clinical samples are discussed, and potential future directions are identified. (C) 2015 Elsevier Inc. All rights reserved.</P>

Energy Efficiency Modelling and Analyzing Based on Multi-cell and Multi-antenna Cellular Networks

( Xiaohu Ge ),( Chengqian Cao ),( Minho Jo ),( Min Chen ),( Jinzhong Hu ),( Iztok Humar ) 한국인터넷정보학회 2010 KSII Transactions on Internet and Information Syst Vol.4 No.4

In this paper, the relationship between the energy efficiency and spectrum efficiency in a two-cell cellular network is obtained, and the impact of multi-antenna on the energy efficiency of cellular network is analyzed and modeled based on two-state Markovian wireless channels. Then, the energy efficiency of multi-cell cellular networks with co-channel interference is investigated. Simulation results verify the proposed model and the energy-spectrum efficiency tradeoffs in cellular networks with multi-antenna and co-channel interference.