Integrated photonic devices for electromagnetic wave sensing, optical true time delay, and trace gas sensing

Investigations on how informative signals interact with optical light wave propagating in integrated photonic devices have been emerging research topics for various sensing and high-speed communication applications. These have become attractive research fields since integrated photonic devices offer unparalleled advantages such as high sensitivity, high-density integration, low power consumption, and great electromagnetic interference immunity. Among all available material platforms for integrated photonic devices, silicon is one of the ideal materials since silicon has excellent optical waveguides properties such as high transparency and high refractive index in optical communication wavelengths. These properties enable low loss and compact on-chip silicon photonic devices. Also, silicon photonic devices benefit from mature silicon-based semiconductor nanofabrication facilities; therefore, they can be fabricated with low cost. On the other hand, silicon photonic devices built on typical silicon dioxide-based silicon-on-insulator wafers can’t be operated beyond the wavelength of 3.5 μm due to high intrinsic mid-infrared absorption of silicon dioxide. Indium phosphide becomes an alternative candidate due to low optical loss. In addition, indium phosphide-based quantum cascade lasers provide narrowband tunable continuous-wave room-temperature emission in the entire mid-infrared spectral range from 3-11 μm which makes monolithically integrated devices possible. Wide varieties of photonics devices on both silicon and indium phosphide platforms have been demonstrated so far such as high-speed modulators, low loss waveguides, couplers, optical phased arrays, and sensors. In this dissertation, silicon integrated photonic devices for electromagnetic wave sensing and optical true time delay lines, as well as indium phosphide-based integrated photonic devices for trace gas sensing, are presented. This dissertation shows that integrated photonic devices are promising for high-performance sensing and novel communication applications.Electrical and Computer Engineerin

How to Create Suitable Augmented Reality Application to Teach Social Skills for Children with ASD

Autism spectrum disorders (ASDs) are characterized by a reduced ability to appropriately express social greetings. Studies have indicated that individuals with ASD might not recognize the crucial nonverbal cues that usually aid social interaction. This study applied augmented reality (AR) with tabletop role-playing game (AR-RPG) to focus on the standard nonverbal social cues to teach children with ASD, how to appropriately reciprocate when they socially interact with others. The results showed that intervention system provides an AR combined with physical manipulatives and presents corresponding specific elements in an AR 3D animation with dialogue; thus, it can be used to help them increase their social interaction skills and drive their attention toward the meaning and social value of greeting behavior in specific social situations. We conclude that AR-RPG of social situations helped children with ASD recognize and better understand these situations and moderately effective in teaching the target greeting responses

A LITERATURE REVIEW OF SUSTAINABLE TOURISM (1990-2016): DEVELOPMENT TRAJECTORY AND FRAMEWORK

Purpose of the study—Tourism is one of the largest and fastest growing industries in the world. Just like an enterprise today, sustainability is the long-term objective pursued by tourism industry. However, little effort has been made to systematically provide sufficient information to academicians and practitioners who have great research interests in sustainable tourism. Therefore, this paper aims to figure out the knowledge mapping of sustainable tourism and to indicate its research hot spots and trends for future research. Methodology—This paper surveys the development trajectory of sustainable tourism using a literature review and classification of articles retrieved from 5 online databases with solo keyword “sustainable tourism” from 1900 to 2016. Main findings—Based on the scope of 641 articles, this study reveals that the number of publication on sustainable tourism has significantly increased since 2006. In addition, these articles are scattered across 125 journals and mostly published in 23 academic journals. The majority of targeted countries/regions for sustainable tourism focus on Asia, Europe and America. Limitation—Restricted to limited knowledge, we make a brief literature survey on sustainable tourism from 1990-2016 to explore how sustainable tourism and its applications have developed in this period. Originality/value—In fact, sustainable tourism is a belief and an overall concept in every tourism activities. Though this research has done lots, it still has rooms to make more complete. Finally, we present a conceptual framework integrating 13 classifications criteria derived from our analysis with 3247 keywords. Most interestingly, we further present a conceptual framework with a visual effect to operationalize the coverage of sustainable tourism. Based on our analysis, any researcher can easily find the popular and right journal to get into it, if he/she is in need, he/she also can roughly know its applications so far and completely get a whole picture of sustainable tourism quickly

THE EFFECTS OF FUNGAL MEDIUM ON HATCHING RATE OF BITING MIDGE

The little black mosquitos, Forcipomyia taiwana, bite human and become one of the most annoying pests in Taiwan. Recently, the population of F. taiwana increases and invades urban and countryside. In order to effectively prevent the harassment of F. taiwana, develop control strategy is urgent and necessary. Our study found that the fungal medium influenced the length and width of the F. taiwana eggs. It also significantly decreased the hatching rate of F. taiwana. Besides, this artificial diet was more non-toxic and environment-friendly than general chemical pesticides. Thus, this study provided critical information to develop potentially useful bait of F. taiwana in the future

Broadband energy-efficient optical modulation by hybrid integration of silicon nanophotonics and organic electro-optic polymer

Silicon-organic hybrid integrated devices have emerging applications ranging from high-speed optical interconnects to photonic electromagnetic-field sensors. Silicon slot photonic crystal waveguides (PCWs) filled with electro-optic (EO) polymers combine the slow-light effect in PCWs with the high polarizability of EO polymers, which promises the realization of high-performance optical modulators. In this paper, a broadband, power-efficient, low-dispersion, and compact optical modulator based on an EO polymer filled silicon slot PCW is presented. A small voltage-length product of V{\pi}*L=0.282Vmm is achieved, corresponding to an unprecedented record-high effective in-device EO coefficient (r33) of 1230pm/V. Assisted by a backside gate voltage, the modulation response up to 50GHz is observed, with a 3-dB bandwidth of 15GHz, and the estimated energy consumption is 94.4fJ/bit at 10Gbit/s. Furthermore, lattice-shifted PCWs are utilized to enhance the optical bandwidth by a factor of ~10X over other modulators based on non-band-engineered PCWs and ring-resonators.Comment: 12 pages, 4 figures, SPIE Photonics West Conference 201

Direct effects of caffeine on osteoblastic cells metabolism: the possible causal effect of caffeine on the formation of osteoporosis

BACKGROUND: Caffeine consumption has been reported to decrease bone mineral density (BMD), increase the risk of hip fracture, and negatively influence calcium retention. In this study, we investigated the influence of caffeine on the osteoblasts behaviour. METHOD: Osteoblasts derived from newborn Wistar-rat calvaria was used in this study. The effects of various concentrations of caffeine on bone cell activities were evaluated by using MTT assay. Alkaline phosphatase (ALP) staining, von Kossa staining and biochemical parameters including ALP, lactate dehydrogenase (LDH), prostaglandin E(2 )(PGE(2)) and total protein were performed at day 1, 3, and 7. DNA degradation analysis under the caffeine influence was also performed. RESULTS AND DISCUSSION: The results showed that the viability of the osteoblasts, the formation of ALP positive staining colonies and mineralization nodules formation in the osteoblasts cultures decreased significantly in the presence of 10 mM caffeine. The intracellular LDH, ALP and PGE(2 )content decreased significantly, the LDH and PGE(2 )secreted into the medium increased significantly. The activation of an irreversible commitment to cell death by caffeine was clearly demonstrated by DNA ladder staining. CONCLUSION: In summary, our results suggest that caffeine has potential deleterious effect on the osteoblasts viability, which may enhance the rate of osteoblasts apoptosis