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This dissertation offers a constructive work on the doctrine of the (im)passibility of the triune God. Two major views have traditionally been advanced in the history of Christian theology in respect of this doctrine: divine impassibility and divine passibility. A mediating position between impassibilism and passibilism has also arisen in more recent years. This dissertation follows the mediating position and posits that the triune God is both impassible and passible - the immanent Trinity is impassible, and the economic Trinity is passible. This dissertation differs from other recent works on the doctrine of the (im)passibility in two important ways. First, this thesis considers how the self-moving God of the Trinity moves himself actively and is moved by himself passively ad intra before considering how he is moved by the world ad extra. Second, this thesis introduces a new way of understanding the way in which the eternal actions (and corresponding passions) of the divine persons condition one another - the 'dynamic reciprocity model'. This dissertation unfolds as follows. The first chapter briefly sketches the recent history of the doctrine of divine (im)passibility from the early nineteenth century to the contemporary era, and outlines the central arguments of the impassibilists and passibilists during this period. The second and third chapters attend in detail to the arguments of a select sample of mediating theologians and consider how they exposit divine (im)passibility. The fourth and fifth chapters move to the constructive aspect of this dissertation by considering the characteristics of and relationship between the immanent Trinity and the economic Trinity as these are illuminated by the dynamic reciprocity model. The conclusion concisely rehearses the key contours of the dissertation and then sets out some of the constructive prospects for future research on the theme of the doctrine of the (im)passibility of God.

This thesis investigates the Park Chung Hee model (PCHM). This term refers to a South Korean variant of the East Asian model of capitalism-particularly, the historical model that guided the rapid and sustained growth of the economy since the mid-1960s. This historical investigation is theoretically informed by a cultural political economy of variegated capitalism (VarCap-CPE) that enables a differential and integral exploration of both historical and contemporary capitalism. In this context, my contribution is twofold. The first is theoretical. While a theoretically informed historical investigation into East Asian capitalism requires an approach to (post-)colonialism, imperialism and hegemony as a prerequisite, VarCap-CPE has still not fully integrated such an approach into its analytical framework. So, my first aim is to improve this paradigm by drawing on Marx's insights into colonialism, the world market, and international hegemony and propose how they might be put in their place, provisionally, in a VarCap-CPE analysis. My second goal is empirical. Based on the enhanced version of the VarCap-CPE, I aim to give a better account of the PCHM than previous literature in political economy. Specifically, I show how the model was informed by two contradictory state strategies: (1) the fascist and autarkic state strategies of Imperial Japan; and (2) the liberal and free trade-oriented developmentalism, based on W.W. Rostow's modernization theory. I thereby demonstrate that the PCHM was self-contradictory and, in this context, present it as a "chimerical" model that combines in a contradictory manner the DNA of two rival species. On this basis, I provide an integral account of its seemingly miraculous performance as well as the dilemmas, contradictions and crisis-proneness that beset it. In addition, unlike much of the extant literature on the Park model, my analysis permits theoretically consistent further research into its crisis and subsequent neoliberalisation.

Technological innovation has enabled tiny devices to participate in pervasive com- puting. Such devices are particularly vulnerable to security and privacy threats, because of their limited computing resources and relatively weak physical security. We investigate possible cryptographic solutions to security and privacy problems arising in two kinds of emerging pervasive computing networks: Personal Area Net- works (PANs) and the EPCglobal Network. A number of key management schemes have been proposed for use in PANs, but these schemes only support key management within a PAN. However, as people are increasingly equipped with multiple wireless devices, PANs are likely to be intercon- nected to share information or services. We introduce a term, iPANs, to name such interconnected PANs. We define system models and design goals for key manage- ment in iPANs, and propose a novel security initialisation scheme for use in iPANs. The proposed scheme achieves desirable security and efficiency properties by making use of the unique characteristics of PANs. The EPCglobal Network is designed to give efficiency and cost savings in and beyond the supply chain using Radio Frequency Identification (RFID) technology; however, privacy threats affecting such networks are particularly serious. We construct a formal privacy model for RFID systems accurately reflecting adversarial threats and power. We then give brief privacy analysis for the existing privacy-enhanced RFID schemes which have received wide attention in the literature. We then construct a secure refresh-based RFID system based on re-encryption techniques, and prove its privacy using the defined privacy model. Finally, we show that the proposed scheme can greatly enhance the security and privacy of EPC tags, making the maximum use of given tag functionalities as specified in the standards.

Laser plasma interaction can be used to generate extremely strong and localized electromagnetic fields. Fields in excess of 100GV/m are routinely generated in small regions with dimensions in the order of microns. These fields can in turn generate charged particle beams of comparable dimensions moving with relativistic velocities. These ultrashort, tightly focused, and often structured beams are capable of delivering high current and/or power beams within order of femtoseconds, making them promising for applications such as nuclear fusion, pulsed neutron generation, electromagnetic radiation generation, and cancer therapy. This dissertation presents two different mechanisms for generating such par-ticle beams consisting of electrons or ions using laser-plasma interaction. Simple analytical models to describe the respective processes and guide experimental implementations are developed. First-principle particle-in-cell simulation re- sults are presented to support the analytical predictions, with parameters relevant to State-of-the-Art laser systems. Chapter 2,3 presents the Carrier-Envelope-Phase(CEP) controlled electron injection mechanism into an (Expanding) Periodically Undulating Bubble ((E)PUB). When an intense near-single-cycle laser pulse or a self-steepened pulse propagates in plasma, it can excite a periodically undulating plasma bubble propagating close to speed of light. The undulation can trigger or suppress electron injection into the plasma bubble, generating longitudinally modulated ultra-relativistic beams with periodicity close to or shorter than a laser wave length. Chapter 2 considers a long-wavelength near-single cycle laser copropa gating with a shorter-wavelength multi-cycle pulse. During the initial stage of propagation, the near-single cycle laser generates periodic undulations, injecting several ultrashort bunches with sub-femtosecond durations. It quickly loses energy to the plasma, and the multi-cycle pulse stably accelerates the injected electrons to a higher energy. Chapter 3 considers a different implementation where a high-power few-cycle laser pulse self-steepens. In this scenario, the plasma bubble undergoes both undulation and expansion, and the electron is in- jected into a dynamically evolving bubble which traps and accelerates the electrons throughout the laser propagation in the plasma. Semi-analytical Hamiltonian model is developed to model both cases, showing good agreement with the First-Principles simulation results. The injected bunch profile can be controlled via the laser’s CEP, polarization, power, and plasma density, and provides a robust platform for controlling the electron beam’s spatio-temporal profile. Chapter 4 explores how the hole-boring radiation pressure acceleration (HB-RPA) mechanism of ion acceleration can be used to focus and accelerate ion beams to a few-micron spot size. When a circularly polarized laser is incident on a overdense plasma surface, it initially pushes away the opaque electrons forward. The ions are then dragged forward via the charge-separation force. It turns out that adequate front-surface shaping, i.e. a parabolic shape, can accel- erate and focus a large flux of ions into a well-defined focal length. Furthermore, a relatively flat laser transverse intensity profile can maintain the focusing front-surface, enabling a high-flux ion beam that can focus at an arbitrary focal length. The scheme is applicable for a wide power range of lasers, ranging from sub-PW to tens-of-PW laser systems and can accelerate multi-species ion beams, forming a monoenergetic ion beam. The accelerated multispecies ion beam copropagating with the electron evolves due to the coupling between the hot electron pressure and massive ions, setting the limit to focusing. We conclude with future directions for research, including open questions and considerations for experimental implementation.

With the advancement of equipment and the development of technology, the manufacturing process is becoming more and more advanced. This appears as an advanced manufacturing process that uses innovative technology, including robotics, artificial intelligence, and autonomous systems. Additive manufacturing (AM), also known as 3D printing, is the representative advanced manufacturing technology that creates 3D geometries in a layer-by-layer fashion with various types of materials. However, quality assurance in the manufacturing process requires high expectations as the process develops. Therefore, the objective of this dissertation is to propose innovative methodologies for process monitoring and control to achieve quality assurance in advanced manufacturing. The development of sensor technologies and computational power offer process data, providing opportunities to achieve effective quality assurance through a machine learning approach. Hence, exploring the connections between sensor data and process quality using machine learning methodologies would be advantageous. Although this direction is promising, some constraints and complex process dynamics in the actual process hinder achieving quality assurance from the existing machine learning methods. To address these challenges, several machine learning approaches assisted by the physics knowledge obtained from the process have been proposed in this dissertation. These approaches are successfully validated by various manufacturing processes, including AM and multistage assembly processes. Specifically, three new methodologies are proposed and developed, as listed below. -To detect the process anomalies with imbalanced process data due to different ratios of occurrence between process states, a new Generative Adversarial Network (GAN)-based method is proposed. The proposed method jointly optimizes the GAN and classifier to augment realistic and state-distinguishable images to provide balanced data. Specifically, the method utilizes the knowledge and features of normal process data to generate effective abnormal process data. The benefits of the proposed approach have been confirmed in both polymer AM and metal AM processes. -To diagnose process faults with a limited number of sensors caused by the physical constraints in the multistage assembly process, a novel sparse Bayesian learning is proposed. The method is based on a practical assumption that it will likely have a few process faults (sparse). In addition, the temporal correlation of process faults and the prior knowledge of process faults are considered through the Bayesian framework. Based on the proposed method, process faults can be accurately identified with limited sensors. -To achieve online defect mitigation of new defects that occurred during the printing due to the complex process dynamics of the AM process, a novel Reinforcement Learning (RL)-based algorithm is proposed. The proposed method is to learn the machine parameter adjustment to mitigate the new defects during the printing. The method transfers knowledge learned from various sources in the AM process to RL. Therefore, with a theoretical guarantee, the proposed method learns the mitigation strategy with fewer training samples than traditional RL. By overcoming the challenges in the process, the above-proposed methodologies successfully achieve quality assurance in the advanced manufacturing process. Furthermore, the methods are not designed for the typical processes. Therefore, they can easily be applied to other domains, such as healthcare systems.

In dense urban settings, efficient use of land is a crucial issue. Especially, urban parks take a large amount of space in high land value areas. Creating an attractive park environment for current and future visitors has the potential to increase the benefits provided by parks to surrounding communities as well as individual park visitors (Dramstad, Tveit, Fjellstad, & Fry, 2006; Roberts, McEachan, Margary, Conner, & Kellar, 2016; Whyte, 1980). This study provides models to predict the number of annual visitors to parks, and identifies the associations between park visitations and environmental factors in parks with a specific focus on medium sized neighborhood parks. The main research questions that this study addresses include the followings. Are the proportions of specific land covers (tree, water, and building) associated with visitation volumes after removing the effects from park land size and demographic variables? If so, what are the characteristics and magnitudes of the associations? This study uses neighborhood parks in Tokyo, Japan as its samples. Among more than 5,000 official urban parks in the 23 central wards of Tokyo, 185 medium-sized parks between 1ha and 10ha were selected. The annual visitation to parks was estimated through cell-phone GPS records. This GPS processing method effectively estimates visitation to medium sized parks that oftentimes are impossible to acquire. Through this application, this study exemplifies how newly emerging industry scale data can contribute to understanding of everyday activities of people that can aid more efficient planning and design (Calabrese, Diao, Di Lorenzo, Ferreira, & Ratti, 2013; Girardin, Vaccari, Gerber, Biderman, & Ratti, 2009). This study investigates the research questions through both OLS and multi-level models. First, a baseline model with three most probable factors - park size, surrounding population, and building footprint - were carefully established. The associations between land cover variables and visitation volumes were estimated on top of the baseline model. To enable a more robust conclusion, several sensitivity tests were conducted. The final baseline model found to have a very high fit (R2=0.8628), and the estimation remained robust when multi-level modeling was introduced. When several models were tested, the quadratic relationship between visitation and tree cover percentage appeared clearly and consistently. Although less clear than tree cover percentage, there was a positive association between visitation and water cover percentage in an acceptable significance. Also, the magnitude and certainty of the association between visitation and tree cover percentage remained almost same after water cover was added to the model. This study found there is an approximate optimal value of tree cover, which is 45%. When tree cover percentage increases from 10% to 30%, the number of visitors is likely to go up by 21,696 people yearly and 59 people daily. When tree cover percentage increases from 60% to 80%, the number of visitors is likely to decrease by 22,124 people yearly and 61 people daily. As for water cover, 10% increase in water cover percentage is likely to be related with 14,168 more visitors per year and 39 more visitors per day. The magnitudes of these associations are considerable, even when compared to the baseline factors. For example, 1ha increase in park land area is associated with an increase of 15,527 visitors yearly. These results, although not strictly causal, suggest that design or environmental quality variables in parks are important in attracting more people to parks. Careful design of parks with appropriate amount of diverse environmental elements may be more effective than creating large parks in terms of benefitting individuals and community. Furthermore, considering the high land values of large cities such as Tokyo, these findings can help the government with cost-effective park planning., Open Space; Landscape Diversity; Audit Tool; Tree Cover; Visitation Volume

There is growing public awareness and concern about patient privacy and the potential risks of sharing clinical data for research. While investigators try to collect large amounts of data to increase the statistical power and diversity of the population, patients strive to gain more control of their data, in a way that respects their preferences; they want assurances about protecting their privacy. In this dissertation, I show how we can satisfy both researchers and patients through the novel use and development of data standardization, federated learning, and tiered informed consent algorithms and tools to foster clinical research while protecting patient privacy and preferences.Chapter 1 is an introduction that consists of research background, significance, problem statement, objectives, and thesis organization. Chapter 2 illustrates a distributed, federated network of 12 health systems that harmonized their electronic health records to a common data model to answer clinical questions related to COVID-19 and post these answers online in a privacy-preserving manner. This network is composed of horizontally partitioned data (i.e., complete data about a set of patients are located in different sites and these sites cannot share data at the individual level). Chapter 3 presents a new algorithm and implementation of distributed logistic regression model for vertically partitioned data (i.e., partial data about a patient are located in different participating sites and these sites cannot share those data at the individual level).Chapter 4 delineates how a source database of medical records can be transformed to a destination database following a common data model, under the constraint that an external expert team cannot access to individual level data. While these chapters describe how various institutions could collaborate without sharing individual level data, Chapter 5 explores whether it is feasible for patients to describe their sharing preferences so that a healthcare system can share data according to these preferences, and different ways to elicit these preferences. We found out that most patients are willing to share their data and biospecimens for research even if they were given the choice. Chapter 6 provides a conclusion and future directions for this work.

The dissertation investigates the form of network governance in the context of U.S. homeless service networks (namely continuum of care programs; CoCs). This research examines CoC homeless service networks by applying the institutional collective action (ICA) perspectives to understand the forms of network governance as a reflection of network context. The ICA perspective has been applied to understand the rational behavior of network members for the network governance form to mitigate the collective action problems. The ICA perspective helps understand why network members accept specific governance structures with their expectation to maximize the benefits and minimize the costs and uncertainty in their process of collaboration. This dissertation uses the data of CoC networks and point in time data from the U.S. Department of Housing and Urban Development in 2019 and Census. The data developed for this study offers the homeless incidences, geographical characteristics, and governance structure based on the contact information. For an in-depth understanding, interview by CoC leaders was integrated. This dissertation consists of four essays about 1) Literature review on network governance and the theoretical argument in the ICA framework, 2) Background and network governance of the U.S. homeless service networks, 3) Factors affecting the choice of network administrative organization (NAO) form, and 4) Interviews by the representatives of CoC networks. The findings inform us of the governance structure for the effective service provisions and coordination of actions of network members and about why and how network organizations choose a form of network governance.

Thermal management becomes a significant challenge due to generating more power per unit volume in developing high-power density micro-/nano-sized electronics. The critical feature size of nano- or micro-electronics has already reached less than 10 nm. The thermal conductivity of the semiconducting, dielectric, and metallic materials used in fabricating these microelectronics can be reduced significantly at a small dimension because of increased boundary scattering of phonons and electrons, known as the heat carriers in solids. The size effects on the thermal transport property are considered one of the most fundamental problems for thermal management, which needs to be understood thoroughly for next-generation electronic devices' rational design. This work seeks to advance the understanding of how heat travels in solid materials. Utilizing precise methodologies for characterizing thermophysical properties is the most critical job. Transient thermoreflectance (TTR) and grating imaging techniques are developed to measure thermal conductivity in both lateral and horizontal directions. These techniques are employed to study materials from bulk to nanostructure, including thin-film and nanoparticles, to be characterized. A new regime of phonon transport between ballistic and diffusive transports, called hydrodynamic phonon transport, is observed with a novel method of heat pulse measurement. With thermal characterization using the TTR, four bulk materials, including glass, sapphire, GaAs, and Si are examined for interfacial thermal resistance and cross-plane thermal conductivity. Nanostructures are also tested, such as MoS2 thin-films over a wide range of thicknesses and digital alloy samples of GaAs/InAs. Cu nanoparticles' effective thermal properties are also measured, including heat capacity, density, and thermal conductivity to improve laser sintering technology in the additive manufacturing industry. Thermal characterization using the grating imaging technique, the in-plane thermal conductivity is measured in GaAs/AlAs superlattices and Cu nano-films on Si substrate, representing the bulk and layered structures, respectively. A new regime of phonon transport, hydrodynamic, is observed in graphite using optical heat pulse measurement. The measurement results reveal transient lattice cooling near the adiabatic center of a ring-shaped pump beam at temperatures between 80 and 120 K.

The rate of physical activity (PA) participation decreases from high school to college, and many college students manage to overlook their nutritional necessities. The two issues, in combination, increase the health risk of typically healthy individuals. The Self-Determination Theory has been applied to an education setting to promote autonomy, competence, and relatedness that can be heightened in the presence of gamification strategies when behavior change is the desired outcome. Gamification is the application of game-design elements in non-game contexts. The purpose of this series of studies was to determine 1) how gamification influenced the learner's motivation and performance, 2) how gamification strategies in higher education coursework changed behavior related to PA and healthy eating, and 3) what are the predictors of PA and healthy eating. First, the relationship between gamification and the learner's behavioral change in education was investigated using a meta-analytic review of contemporary research. Second, a study determined the impact of using gamification methods in higher education coursework to change the behavior associated with PA and healthy eating as an experimental design study. Finally, the predictors of PA and healthy eating behavior among first-year college students in gamified and non-gamified courses were identified. The results from Study 1 confirmed that the gamification strategies have a moderate, positive effect on participant’s behavior and test scores. Also, this study examined if age, intervention length, measurement type influences the effectiveness of the gamification intervention. The findings were based on 32 data sets from 18 experimentally designed studies. Study 2 found that health education with gamification approaches has a positive effect on motivating learners to change their walking and healthy eating habits. Finally, Study 3 discovered that healthy eating habits and past PA behavior were predictors of PA participation. Furthermore, sedentary behavior and eating social support were identified as a predictor of healthy eating. Collectively, the research findings support the use of gamification in behavior change coursework among college students. Further, the results suggest that there may be an optimal design for including gamification elements in health-oriented interventions that maximize health outcomes. The series of studies identified specific pedagogical and gamification methods most likely to promote habitually participate in physical activity and health eating among first-year college students. Finally, potential implications for physical education teacher education were described

Customer expectations have been considered as customers' pre-purchase beliefs or evaluative beliefs about a product or service. When making a choice, customers first construct their expectations of what is to come whenever they receive new information within a context that is based on the past events. From firms' perspective, a tension exists between raising expectations to increase initial acceptance/trial and lowering expectations to increase satisfaction, and hence future sales. As such, it should come as no surprise that service firms are interested in better understanding how consumers form expectations about quality to manage customer expectations over time. This thesis comprises of two essays where I demonstrate the role of customer expectation in (1) customer satisfaction and repurchase and (2) strategic customer behavior under bounded rationality and its impact on product switching. In the first essay, I examine the value of measuring customer satisfaction. Many service firms keep track of customer satisfaction ratings, along with objective service performance, after each purchase transaction. I find that customer satisfaction provides additional information about customer purchase behavior over and above objective service performance. Unlike past research, these results are obtained after controlling for within-customer selection (of service encounters). Overall, the results suggest that measuring customer satisfaction is valuable because it helps firms to better predict their economic outcomes. The second essay focuses on customers' product switching behavior based on their expectations under bounded rationality by modeling time-varying customer expectations under imperfect recall and their impact on product switching behavior over time. I find evidence of a decline in carryover of prior expectations and imperfect recall of previous service encounter, which supports my hypothesis on bounded rationality in customer expectations. Furthermore, the results show that customers strategically choose the same alternative that previously results in a free upgrade, anticipating yet another upgrade in a subsequent transaction.

Wireless network localization using Radio Signal Strength (RSS) is considered a classical option in many scenarios because of its convenience and economic feasibility. However, this localization method is easily affected by various influences, such as unknown radio path loss factors, multi-path effects, hardware discrepancies, antenna orientation, and so forth. Among these, multi-path effects have a profound effect on uni-channel RSS measurements in the “microscale”, defined as a small region within the range of several wavelengths of the radio signal and thus degrade to the accuracy of transitional localization methods based on uni-channel fingerprinting. In response to the above limitation, this thesis introduces Harnessing Constructive Interference (HCI), a system for indoor positioning using the phenomenon of constructive interference. The key observation behind the HCI is that peak RSS measurements in the frequency domain, which are results of the constructive interference, feature a relatively small dynamic range. Utilizing this observation, we propose the HCI design to improve the performance of the location estimate. In addition, we provided three profiling methods: symmetric, asymmetric with Spline interpolation and Whittaker- Shannon interpolation to reduce the system overhead. To evaluate, the proposed designs have been implemented on the NU platform and experiments were carried out with 56 sampling positions, 5 anchor nodes, and a collective number of 1,447,800 RSS measurements. By comparing with a representative algorithms, e.g., RADAR [2], it is shown that the proposed HCI system significantly reduces localization errors. Adviser: Ziguo Zhong

Brevisamide was isolated from the red tide dinoflagellate Karenia brevis in 2007. Key features of brevisamide include a substituted tetrahydropyran core and conjugated 3,4-dimethylhepta-2,4-dienal side chain. Total synthesis of brevisamide was highlighted by a stereoselective [4+2]-annulation of a (Z)-crotyl silane to furnish the substituted pyran core and Negishi cross-coupling to construct the conjugated dienal side chain. Successful application of the silane-based annulation methodology provided brevisamide in overall 17 steps and 6.4% overall yield from the known (Z)-crotyl silane. Isatisine A was isolated from the leaf and roots of Isatis indigotica in 2007. Total synthesis of isatisine A commenced with the development of a silyl-directed Mukaiyama-type [3+2]-annulation of an ethoxy allylsilane to construct a tetrahydrofuran core. [3+2]-Annulation reaction of an ethoxy allyl silane with 2-bromocinnamylaldehyde afforded the furan core as a single diastereomer. Further substrate-controlled indole addition and intramolecular copper(I)-mediated amidation provided (+)-isatisine A in overall 12 steps. One-pot Diels-Alder/annulation sequence was developed utilizing a silane-substituted 1,3-diene to give a fused-cyclic scaffold. In this reaction sequence, initial Lewis-acid-promoted Diels-Alder reaction between the silyl-substituted diene and a naphthoquinone constructed an intermediate cyclic allylsilane, and subsequent addition of aldehyde and Lewis acid triggered the annulation to construct a complex cyclic compound with high diastereoselectivity. This one-pot three component reaction sequence allowed for a simple access to various fused-polycyclic compounds, which bear a tetrahydropyran core. Leiodolide A was isolated from the deep-water marine sponge Leiodermatium. Leiodolide A was found to be significantly cytotoxic against HCT-116 human colon carcinoma with IC50 values = 1.4 ug/mL (2.5 uM). Since the natural product leiodolide A was found to comprise less than 0.001% of the dry weight of the sponge, establishing an efficient synthetic method to provide a significant amount of the natural product would be valuable to further biological studies. Our effort to synthesized upper fragment of leiodolide A was conducted through a series of cross-coupling reactions involving Stille coupling. Although proper conditions for the oxidation of (Z)-olefin to introduce the contiguous C15-17 triol system in leiodolide A were not achieved, this synthetic pathway would be useful in the total synthesis of leiodolide A.

Snow and ice mass balance is an important concept to describe the growth or decay of land ice. Mass balance is measured as the difference between the amount of accumulation and the amount of ablation. In that this value could provide the significant information on the sea level rise and the global warming trend, many researchers have been trying to estimate or predict the input to the mass balance from net snow accumulation rates. However, predicting accumulation is not simple because this value varies with time and place. In this study, spatial and temporal characteristics are thus investigated to provide basic information on accumulation. The result represents that the ice cores in central-west and south-east basins are the most influential in total average accumulation over Greenland because of their large magnitude of accumulation. However, when the accumulation data are normalized, other sites (Tunu-N, ACT-04-2, and ACT-04-3) also appear to be important for total ice sheet accumulation. 5-year triangular filter has been adapted to find the correlations between ice cores. Central basins represent the large improvement and the northwest, northeast and southwest basins represent low improvement. The trend of increased signal to noise ratio may be related to the latitude. The correlations between most ice cores decay with distance. Especially, central-east and central-west basins show the strong distance-decay patterns. South east basin also represents relatively high distance decays. Otherwise, north and southwest basins do not represent high distance decay trend consistently. While southwest and southeast basins are located in almost same latitude, these two basins represent different trend regarding correlation and slope. This might be related to the prevailing easterly winds, frequent cyclogenesis, and orographic enhancement. High amount of accumulation in southeast basin might be also related. Over the whole period, temporal autocorrelation was not found in almost every basin, which means one year’s accumulation does not affect the next or last year’s one. Among various topographic or geographic factors, latitude is the most related factor for determining accumulation rates of all ice cores. In case of north and central basins, most topographic factors (Latitude, longitude, elevation, slope, aspect) are highly related to accumulation. Otherwise, southeast and southwest basins exhibit small relations with topographic factors. There is a relationship between NAO and accumulation in central west basin, but magnitude is not large.

The FCC allocated the spectrum of 402-405 MHz for MICS (Medical Implant Communication Services) applications in 1999. The regulations for MICS band apply to devices that support the diagnostic and/or therapeutic functions associated with implanted medical electronics. The implanted devices aid organs and control body functions of patients to support specific treatments, and monitor patients continuously so that necessary action can be taken in advance to avoid serious conditions. To enable to use MICS applications, several requirements must be satisfied. An implanted wireless device should have a small size, consume ultra-low power, and achieve the date rate of at least 200 kbps within 2 m distance. The major challenge is to realize ultra-low power devices. Thus the low-power design of the RF circuit is crucial for MICS applications as the power consumption of the wireless devices is mostly contributed by RF circuits. This thesis investigates low-power design of an LNA and a down-conversion mixer of a receiver for MICS applications. The key idea is to stack an LNA and a mixer, while the LNA operates in the normal super-threshold region and the mixer in the sub-threshold region. In addition, a gm-boosting technique with a capacitor cross-coupled at the LNA input stage is also adopted to achieve a low noise figure (NF) and high linearity, which is critical to the overall performance of the receiver. The mixer operating in the sub-threshold region significantly reduces power dissipation and relaxes the voltage headroom without sacrificing the LNA performance. The relaxed voltage headroom enables stack of the LNA and the mixer with a low supply voltage of 1.2 V. The proposed circuit is designed in 0.18 μm RF CMOS technology. The merged LNA and mixer consumes only 1.83 mW, and achieves 21.6 dB power gain. The NF of the block is 3.55 dB at 1 MHz IF, and the IIP3 is -6.08 dBm.

Today’s semiconductor industry has been significantly changing in its techniques and processes for the fabrication of devices and accordingly, there has been dramatic increase in performance and a reduction in cost. To obtain still higher device performances and still further cost reduction, the dimensions of patterns in integrated circuits should be as small as possible and the 3-dimensional accuracy of multidimensional semiconductor structures should be also achieved as well. The manufacturing of smaller feature dimensions and 3-dimensional devices has been enabled by developments in lithography – the technology which transfers designed patterns onto the silicon wafer. Especially, electron beam lithography is widely adapted in the nano fabrication technology due to its ability to achieve nanometer-scale resolution. The aim of this work is to fabricate test devices by the electron beam lithography possesses and apply them to the test of electron optical systems. In this thesis, we first develop methods to fabricate a high resolution nano scale Fresnel zone plate and 3-dimenstional stair case structure by E-beam lithography. To optimize the fabrication we optimized the lithographic process and the subsequent process steps accounted for proximity effects via a correction program and controlled pattern transfer through reactive ion etching (RIE). The completed devices were tested in a Scanning Electron Microscopy (SEM) and the accuracy of feature parameters were examined by Fast Fourier Transformation methods (FFT). Finally, the application of these structures to the calibration and testing of e-beam systems was explored.

Optical excitation of a sample produces photothermal effects such as a temperature rise, pressure change, refractive index change, and thermoelastic displacement due to absorption of laser radiation in a short pulse or continuous train of pulses. Change of optical path length in tissue in response to pulsed laser irradiation is a photothermal response associated with refractive index change. The detection of laser induced optical path length change may provide useful information for diagnostic biomedical applications such as imaging and sensing. Detection of optical path length change in response to pulsed laser irradiation is associated with a relative strain or stress change. DP-OCT can measure change of relative optical path length between light backscattered from two spatially separated sites. Dye and Superparamagnetic iron oxide nanoparticles (SPION) solutions were used in basic studies to investigate optical path length change in response to pulsed laser irradiation. DP-OCT detection of thermoelastic surface displacement and thermal wave radiometric imaging (TWRI) of arteries of SPIONinjected hyperlipidemic rabbits were conducted to detect atherosclerotic plaques. Studies using both DP-OCT and TWRI showed that pulsed laser irradiation of nanoparicles can improve detection capability of atherosclerotic plaque. Analytical solutions for DP-OCT experiments and TWRI were developed to investigate optical path length change in response to pulsed laser irradiation. Homogeneous planar absorbers and point heat sources in an elastic medium were assumed for dye solutions and SPION in a rabbit artery, respectively. Refractive index change and thermal expansion coefficient of dye solutions were obtained by correlating measured optical path length and temperature increase using the developed analytical solution. Measured thermoelastic surface displacements of rabbit arteries in response to pulsed laser irradiation were consistent with the derived analytical solution. Laser spot size, penetration depth, and nanoparticle distribution determined the rate of thermoelastic surface displacement and decay during and after laser irradiation respectively. In addition, magnitude and phase difference between plaque and background for TWRI was examined using a derived analytical solution. Thermoelastic surface displacement of neural tissue in response to pulsed Ho:YAG laser irradiation was measured by DP-OCT. Thermoelastic displacement does not account for optical stimulation of neural tissue.