System Design and Modeling of Optical Scattering Communications

나ARYA SUDHANSHU 부경대학교 대학원 2022 국내박사

Demand for optical wireless communications (OWCs) is growing at a rapid pace. There is a growing interest from the commercial and the military in having secure, efficient, and high bandwidth OWC systems for tactical applications. An OWC system relies on optical wavelength, ranging from infrared to ultraviolet (UV) to convey a piece of information. With recent advances in the design and manufacturing of UV sources and detectors, optical scattering communication has attracted much interest for diverse applications. Atmospheric scattering in the deep UV band is much higher than other optical bands. This phenomenon enables establishing of a non-line-of-sight (NLOS) link. This thesis is devoted to the system design and modeling of various aspects of optical scattering communications employing ultraviolet wavelength. It provides the most comprehensive NLOS optical scattering communication systems design and modeling. The focus of the studies discussed in the second chapter is to investigate the spatial diversity techniques for optical scattering communications. With the received signal characterized by a continuous waveform detector, the switch and stay combining (SSC) diversity technique is implemented at the receiver over correlated turbulence fading channel. Next, to avoid the requirement of an adaptive threshold in demodulating the on-off keying (OOK) symbol, the SSC diversity technique equipped with M-ary phase-shift keying (MPSK) is presented. The chapter also presents a maximal selection transmit diversity for optical scattering communications. The third chapter presents techniques for optical spectrum sensing for distributed optical scattering communications. First, we develop an energy detection-based optical spectrum sensing for a UV network where each user is equipped with a continuous waveform detector. Second, we propose a new generic blind optical spectrum sensing technique. The proposed technique is based on finding the statistical ratio of the received continuous waveform signal. It does not require prior knowledge of the signal and noise power. Next, we propose two novel cooperative spectrum sensing techniques for optical scattering communication networks with randomly distributed collaborative users pointing in arbitrary directions. In particular, we present centralized- and decentralized-based cooperative spectrum sensing with hard decision fusion. We assume multiple scattering and characterize the received signal by the photon-counting receiver. To obtain the distribution of the received irradiance over the multi-scattering channel, a novel method based on the Mellin transform is proposed. In the centralized technique, all the raw data (in the form of statistically dependent random variables) available at the collaborative users are combined using AND rule for decision, whereas, in the decentralized-based spectrum sensing, instead of sending all the raw data, only one-bit information is required to be sent to the fusion center to make the decision. In the fourth chapter, we present an artificial neural network (ANN) based algorithm to estimate the data. In addition, analytical frameworks are presented to estimate the channel model parameters under different fading distributions. In the fifth chapter, we present a novel state-of-the-art UV-based indoor optical communications. The channel model is developed and analyzed. To ensure that the UV radiations are under allowable safety exposure limits, strict peak and average power constraints are imposed. Based on the power budget, the necessary conditions for the input distribution of the intensity-modulated direct detection (IM/DD) OOK modulated signal are derived. The link gain analysis is presented to investigate the directed line-of-sight (LOS) component and diffused links with multiple reflections and NLOS scattered components. The time-delay statistics for various paths are analyzed. Next, we present a novel multiuser indoor communication over a power-constrained Poisson channel. To reject the interference from multiple users, we present a minimum mean square error (MMSE) receiver. Moreover, a downlink beamforming optimization problem is formulated using second-order cone programming to maximize the received signal-to-interference-plus-noise ratio (SINR). The proposed multiuser system is also realized in the experiment. The influence of the control parameter, that is, the average-to-peak power ratio, on the performance is investigated. The next chapter is dedicated to implementing orbital angular momentum (OAM) with UV communications. As a method to improvise the reliability of the UV communication system, we develop an OAM-based UV communication. Our work presents a significant increase in the UV channel capacity. The seventh chapter presents a novel decentralized and self-organizing non-line-of-sight (NLOS) UV-based V2V communication (IVC). Experiments for proof-of-principle purposes were conducted with two vehicles in both stationary and time-varying UV channels. It is demonstrated that the proposed UV-IVC is capable of providing low-cost, low-power, and NLOS capable V2V communications with acceptable performance. The last chapter concludes and summarizes the optical scattering communication systems developed in the previous chapters. In conclusion, the results and analysis presented in this thesis show the feasibility of employing optical scattering communication technologies in next-generation free-space optical communications. The future scope of optical scattering communications is also elaborated in the conclusion.

통합 마케팅 커뮤니케이션(IMC)에서의 온라인 마케팅 효과에 관한 연구

Arya, Kumari 중부대학교 2020 국내석사

Optimal instruction scheduling for a class of vector processors : an integer programming approach

Arya, Siamak University of Michigan 1983 해외박사

Effects of chemical composition, section size and different nodularizer on the microstructure and mechanical properties of C.V. graphite cast iron

Arya, Wijayamurti Yeungnam University 2014 국내석사

Korea-Indonesia International Comparative Study For Development of Sustainable Ecotourism Models : In Bali’s Natural Forests

Arya, Kusdyana I Putu Gede Park Chung Hee School of Policy and Saemaul, Yeung 2021 국내석사

For almost six decades, forest resources have emerged a significant role in supporting Indonesia’s economic development achieving development goals. Meanwhile, over time the forest condition has shown a significant decrease of productivity forest, even has caused an increased level of degradation forest and deforestation. On the other side, a rapidly growing sector of the tourism industry provides the possibility of nature-based tourism to develop as well. For specific interests’ activities ranging from educational, healing, adventure through the merge with arts and culture, local heritage, etc. Nature-based tourism emerged as an incentive to retain and manage their wildlife and hence the crucial biodiversity life. The main research objective is to investigate resident's satisfaction in terms of obtaining stakeholder's perceptions currently about the management of Indonesia's natural forest that has benefited the local community, and stakeholder's roles in terms of contributing to achieving sustainable ecotourism development in Bali's Natural forests. The grounded theory method (GTM) was applied in this research, and data were obtained from in-depth interviews on two study areas are the Buyan-Tamblingan Nature Recreation Park and Bali Barat National Park. Respondent was divided into three different stakeholder groups who were selected based on their role, namely local leaders/ local prominent, official governments, and others (villager, officer, private sector). By the GTM will be obtained stakeholder's perceptions, identified factors relate to nature-forests functions and implications to the human beings and also providing the possibilities developing ecotourism models to increasing economic citizen's welfare towards sustainable ecotourism. Data were obtained from in-depth interviews with fifteen respondents who were selected as "a key person" in order to become representative of their communities in two locations of Bali's nature forest that had been established as the conservation forests and then classified into three different stakeholder's groups. Local community engagements were essential predictors of sustainable ecotourism. Expectancy shows the proportions of different roles or services of stakeholders in each sector. Therefore, the role of stakeholders’ particularly local communities is very conscious and needs to improve able to assist the increasing nature preservation by giving their voluntary services, behaviors for promoting their local potencies in their area as support for development ecotourism models. In addition, differences in socio-cultural conditions between countries also hinder the successful Korean recreation model's adaptation process. It was shown from there are differences of several data such as from comparative study between forestry statistical data of both countries that there is differences focus of management policies that because several data has been presented could not compare each other. Meanwhile, regarding the formulation of the foundation of the substantive theory through considering six selective codings labeled that have been found, which are validated with the explanation of the phenomena theory. The researcher tries to build a theory for the ecotourism model in the study area in Bali's natural forest. We call it "locals-based natural recreation" towards sustainable ecotourism and enriching for people. The researcher has emphasized the notion of locals interpreted as a local potential established in villages and communities such as local wisdom, culture, religion, and habits in communities, as well as about natural potential in the forest that requires preserving. Finally, particularly relate with there are limitations due to Covid-19 and uncertainly about the policy of tourism for international tourists in Bali that becomes difficult for the researcher even though he has a chance to meet with respondents directly. In the case of Indonesia that has presented ecotourism development has focused on local uniqueness and natural conditions and be measured by a socio-cultural process that is sustainable and involves the local community; sustainable natural and environmental resource cycle; economic processes that can provide sustainable benefits. Moreover, on average that stakeholder perception about nature satisfaction is obvious clearly of increasing the role of stakeholders’ particularly local communities that has increased to participate in process of recovering nature and its preservation by providing their voluntary involvement, awareness, and willingness to participate in case promoting the local potencies to supporting for development tourism models based natural recreation. Keywords: Nature-based recreation and Ecotourism, Sustainable tourism, Grounded Theory, Korea-International Comparative study, community-based ecotourism

Maintaining DNA integrity of canine frozen-thawed sperm using iodixanol supplementation

Abdillah, Dimas Arya 서울대학교 대학원 2019 국내석사

정액 동결은 인공 수정(AI)을 위한 필수 단계로 간주되어왔고, 1930년대 후반과 1940 년대 초반에 정액 동결법이 최초로 개발되었다. 그러나 높은 유전적 가치를 지닌 생물체와 개의 멸종위기종을 보존하기 위해 융해 후에도 생식능을 가진 정자의 수를 유지시키는 것은 항상 어려운 연구로 여겨졌다. 성공적인 정액 동결은 성매개질환의 예방, 운송 중 동물의 스트레스 감소 등과 같은 여러 이점을 가져올 수 있다. 융해 후 정자의 품질은 성공적인 인공 수정을 위한 중요한 요소이다. 본 연구의 목적은 동결 보호제의 첨가를 이용하여 개의 정액 동결을 향상시키는 것이다. 동결 보호제는 정자의 융해 후 운동성을 증진시키기 위한 동결 희석액의 기본 요소 중 하나이다. 그러나 동결 보호제와 같은 희석액에 일부 화학 물질을 첨가하면 정자의 품질에 해로운 영향을 미치는 경우도 존재한다. 따라서 개의 정액에서 동결 보존제 첨가의 최적 농도를 결정하는 것이 요구되었다. OptiprepTM (iodixanol 60 % in water)은 여러 종에서 희석액으로 널리 사용되고 있다. 그러나 개의 정액동결에서의 OptiprepTM 첨가에 대한 연구는 이루어지지 않았다. OptiprepTM 농도 결정은 상온에서 1 시간 이내에 수행되었다. 해당 연구는 대조군과 처리군 사이의 신선 정자의 정자 생존 능력과 운동학적 지표를 비교했다. 결과적으로, 2.5% 농도의 OptiprepTM 이 대조군 및 다른 군에 비교하여 최적의 농도였다. 이 결과를 바탕으로 정액동결 과정에서 2.5% 농도의 OptiprepTM를 분석하였다. 2.5 % OptiprepTM 처리군에서의 동결-융해 정자는 대조군에 비해 더 우수한 품질을 보였다. 처리군의 운동능은 대조군보다 유의적으로 향상되었다. 또한, 2.5 % OptiprepTM을 이용한 정액동결은 정자의 품질을 향상시키는데 대조군보다 더욱 효과적이었다. 또한 프로타민 -2 (PRM2), 프로타민 -3 (PRM3), 항 - 세포 사멸 유전자 (BCL2) 및 정자 첨체 관련 유전자 -3 (SPACA3)의 발현의 높은 발현과 ROS 조절자 (ROMO1) 및 세포 자멸사 유전자 (BAX)의 낮은 발현은 2.5 % OptiprepTM 처리가 정자에 유익하다는 것을 보여 주었다. 또한 해동 과정 후에 OptiprepTM 처리군에서 살아있는 정자의 비율이 대조군보다 유의적으로 높게 나타났다. CCM에서 배양 후 반응 첨체를 가진 살아있는 정자의 수는 OptiprepTM 처리군에서 대조군보다 더 높았다. 점액 침투 검사에서 3cm 마커를 이동한 정자의 수 또한 대조군보다 높았다. 결론적으로, 개의 정액 동결시 Iodixanol 처리는 해동 후 정자의 품질을 유의적으로 향상시켰다. Iodixanol의 처리는 ROS 수준을 감소시키고 수정능 획득을 줄이며 생존력, 운동성 및 번식능을 증가시킬 수 있다. Sperm cryopreservation has been considered as an essential step for artificial insemination (AI). The cryopreservation sperm was found first time in the late 1930s and early 1940s. However, the number of fertile spermatozoa after post-thawing has always been a challenge for researchers to preserve high genetic value organism and endangered species of dogs. In addition, successful sperm cryopreservation can bring several benefits such as preventing sexually transmitted disease, reducing animal stress during transportation, and etc. Because of those reasons above, the quality of sperm post-thawing has become the main concern to overcome successful artificial insemination. Thus, the purpose of this study was to improve canine sperm cryopreservation quality using cryoprotectant agent supplementation. Cryoprotectant is one of the basic parts in the freezing extender to develop post-thawing motility quality of sperm. However, adding cryoprotectant into extender sometimes gives deleterious effect to sperm quality. Therefore, it is needed to find out the optimum concentration of the cryoprotectant agent in canine sperm. In this study, we treat sperm with OptiprepTM (iodixanol 60% in water) as a cryoprotectant supplementation. It has been widely used as supplementation in several species. Nonetheless, there is no study on OptiprepTM supplementation in canine sperm cryopreservation. Determining OptiprepTM concentration was performed at room temperature within 1 hour. We compared sperm viability and kinematic parameter of fresh spermatozoa in control and treatment groups. As a results, 2.5% concentration of OptiprepTM was the optimum concentration compared to the control group. Based on experiment results in fresh spermatozoa, we decide to analyze 2.5% concentration of OptiprepTM in cryopreservation process. Frozen–thawed spermatozoa in 2.5% OptiprepTM treatment group showed better quality in motility compared to the control. In addition, the comparison between control and treatment group mentioned that cryopreservation using 2.5% OptiprepTM was more useful in enhancing high sperm quality. Moreover, improved expression level of protamine-2 (PRM2), protamine-3 (PRM3), anti-apoptotic gene (BCL2), and sperm acrosome associated-3 (SPACA3), together with lower expression ROS modulator (ROMO1) and pro-apoptotic gene (BAX) than control, showed that 2.5% OptiprepTM treatment was advantageous for the spermatozoa. Furthermore, after thawing process, the quantity of live spermatozoa in OptiprepTM group showed significantly higher than control. The number of live capacitated spermatozoa which undergoes acrosomes reaction post-incubation in CCM was greater in the OptiprepTM treated group than in the control. In mucus penetration test, the number of sperm traveled three cm marker was also higher than the control. In conclusion, the Iodixanol supplementation in canine sperm cryopreservation significantly enhanced post-thawing sperm quality. Iodixanol supplementation can reduce ROS levels, decrease cryocapacitation, and increase viability, motility, and fertility

Discovery stories in the science classroom

Arya, Diana Jaleh University of California, Berkeley 2010 해외박사(DDOD)

소속기관이 구독 중이 아닌 경우 오후 4시부터 익일 오전 9시까지 원문보기가 가능합니다.

School science has been criticized for its lack of emphasis on the tentative, dynamic nature of science as a process of learning more about our world. This criticism is the guiding force for this present body of work, which focuses on the question: what are the educational benefits for middle school students of reading texts that highlight the process of science in the form of a discovery narrative? This dissertation traces my journey through a review of theoretical perspectives of narrative, an analysis of first-hand accounts of scientific discovery, the complex process of developing age-appropriate, cohesive and engaging science texts for middle school students, and a comparison study (N=209) that seeks to determine the unique benefits of the scientific discovery narrative for the interest in and retained understanding of conceptual information presented in middle school science texts. A total of 209 middle school participants in nine different classrooms from two different schools participated in the experimental study. Each subject read two science texts that differed in topic (the qualities of and uses for radioactive elements and the use of telescopic technology to see planets in space) and genre (the discovery narrative and the "conceptually known exposition" comparison text). The differences between the SDN and CKE versions for each topic were equivalent in all possible ways (initial introduction, overall conceptual accuracy, elements of human interest, coherence and readability level), save for the unique components of the discovery narrative (i.e., love for their work, acknowledgement of the known, identification of the unknown and the explorative or experimental process to discovery). Participants generally chose the discovery narrative version as the more interesting of the two texts. Additional findings from the experimental study suggest that science texts in the form of SDNs elicit greater long-term retention of key conceptual information, especially when the readers have little prior knowledge of a given topic. Further, ethnic minority groups of lower socio-economic level (i.e., Latin and African-American origins) demonstrated an even greater benefit from the SDN texts, suggesting that a scientist's story of discovery can help to close the gap in academic performance in science.

Contextual Bandits with Delayed Feedback Using Randomized Allocation

Arya, Sakshi ProQuest Dissertations & Theses University of Minn 2020 해외박사(DDOD)

소속기관이 구독 중이 아닌 경우 오후 4시부터 익일 오전 9시까지 원문보기가 가능합니다.

Contextual bandit problems are important for sequential learning in various practical settings that require balancing the exploration-exploitation trade-off to maximize total rewards. Motivated by applications in health care, we consider a multi-armed bandit setting with covariates and allow for delay in observing the rewards (treatment outcomes) as would most likely be the case in a medical setting. We focus on developing randomized allocation strategies that incorporate delayed rewards using nonparametric regression methods for estimating the mean reward functions. Although there has been substantial work on handling delays in standard multi-armed bandit problems, the field of contextual bandits with delayed feedback, especially with nonparametric estimation tools, remains largely unexplored. In the first part of the dissertation, we study a simple randomized allocation strategy incorporating delayed feedback, and establish strong consistency. Our setup is widely applicable as we allow for delays to be random and unbounded with mild assumptions, an important setting that is usually not considered in previous works.We study how different hyperparameters controlling the amount of exploration and exploitation in a randomized allocation strategy should be updated based on the extent of delays and underlying complexities of the problem, in order to enhance the overall performance of the strategy. We provide theoretical guarantees of the proposed methodology by establishing asymptotic strong consistency and finite-time regret bounds. We also conduct simulations and real data evaluations to illustrate the performance of the proposed strategies.In addition, we consider the problem of integrating expert opinion into a randomized allocation strategy for contextual bandits. This is also motivated by applications in health care, where a doctor's opinion is crucial in the treatment decision making process. Therefore, although contextual bandit algorithms are proven to work both theoretically and empirically in many practical settings, it is crucial to incorporate doctor's judgment to build an adaptive bandit strategy. We propose a randomized allocation strategy incorporating doctor's interventions and show that it is strongly consistent.

Studies of platelet glycoprotein Ib-IX-V adhesion tovon Willebrand factor using optical tweezers

Arya, Maneesh Rice University 2004 해외박사(DDOD)

소속기관이 구독 중이 아닌 경우 오후 4시부터 익일 오전 9시까지 원문보기가 가능합니다.

The first stage in hemostasis and thrombosis is the binding of the platelet membrane receptor, glycoprotein (GP) Ib-IX, to its ligand, von Willebrand factor (VWF), in the subendothelium. Using an optical tweezers system, we have measured the binding strength of: (1) VWF variants (unusually large VWF (ULVWF), plasma VWF, and isolated VWF A1 domain) to GP Ib-IX receptors; (2) GP Ib-IX variants (receptors with human-canine chimeric sequences in the leucine-rich domain, and truncated receptors) to plasma VWF; (3) plasma VWF to gain-of-function (GOF) and loss-of-function (LOF) mutated GP Ib-IX receptors; (4) VWF Al domain to clustered GP Ib-IX receptors; and (5) ULVWF multimers to GP Ib-IX in the presence of the VWF cleaving protease (ADAMTS-13) and other modulators. In addition, we dynamically measured unbinding force profiles between A1 and GP Ib-IX at loading rates ranging from 200--20,000 pN/s and examined the relationship between bond rupture force and loading rate. In the absence of shear stress, ULVWF multimers formed spontaneous high-strength bonds with GP Ib-IX, while plasma VWF required exogenous modulators. The strength of individual bonds formed with GP Ib-IX was similar for both ULVWF and the isolated A1-domain and greater than those of plasma VWF induced by an exogenous modulator. We observed ULVWF/GP Ib-IX binding was completely abolished with the addition of either ADAMTS-13 or plasma cryosupernatant. We found that the putative single bond strengths between A1 and GP Ibalpha GOF mutants were significantly greater than the A1/wild-type GP Ib-IX bond at all loading rates examined. In addition, the GP Ibalpha LOF mutants exhibited significantly lower putative single bond strengths with A1 than the wild-type receptors. The experiments involving the adhesion of either chimeric or truncated GP Ib-IX receptors to VWF illustrated the importance of various regions of the glycoprotein in properly binding VWF. The minimal detachment force between GP Ib-IX and A1 or plasma VWF doubled after an exogenous clustering agent was added, thereby demonstrating the importance of avidity, as opposed to affinity, modulation. Finally, we observed a linear relationship between the rupture force and the logarithm of the loading rate, consistent with the Bell Model.

Regulator of G-protein signaling 5 is expressed in hepatic stellate cells and moderates the fibrotic response to injury

Bahrami, Arya J University of Washington 2014 해외박사(DDOD)

소속기관이 구독 중이 아닌 경우 오후 4시부터 익일 오전 9시까지 원문보기가 가능합니다.

Liver fibrosis is mediated by hepatic stellate cells (HSCs), which respond to a variety of cytokine and growth factors to moderate the response to injury and create extracellular matrix at the site of injury. G-protein coupled receptor (GPCR)-mediated signaling, via endothelin-1 (ET-1) and angiotensin II (AngII), increases HSC contraction, migration and fibrogenesis. Regulator of G-protein signaling-5 (RGS5), an inhibitor of vasoactive GPCR agonists, functions to control GPCR-mediated contraction and hypertrophy in pericytes and smooth muscle cells (SMCs). Therefore we hypothesized that RGS5 controls GPCR signaling in activated HSCs in the context of liver injury. In this study, we localize RGS5 to the HSCs and demonstrate that Rgs5 expression is regulated during carbon tetrachloride (CCl4)-induced acute and chronic liver injury in Rgs5LacZ/LacZ reporter mice. Furthermore, CCl4 treated RGS5-null mice develop increased hepatocyte damage and fibrosis in response to CCl4 and have increased expression of markers of HSC activation. Knockdown of Rgs5 enhances ET-1-mediated signaling in HSCs in vitro. Taken together, we demonstrate that RGS5 is a critical regulator of GPCR signaling in HSCs and regulates HSC activation and fibrogenesis in liver injury.