京都大学 / 0048 / 新制・課程博士 / 博士(情報学) / 甲第22585号 / 情博第722号 / 新制||情||124(附属図書館) / 京都大学大学院情報学研究科数理工学専攻 / (主査)教授 梅野 健, 教授 山下 信雄, 教授 守倉 正博 / 学位規則第4条第1項該当 / Doctor of Informatics / Kyoto University / DFAM

International Telemetering Conference Proceedings / October 30-November 02, 1995 / Riviera Hotel, Las Vegas, Nevada / The use of low windload FLAPS™ antennas in telemetry tracking systems yields sizable savings in system cost due to the reduced requirements imposed on the pedestal assembly and on the underlying support structure. Traditionally the use of these antennas has been limited to applications in which frequency bandwidths did not exceed 10-13%. This paper describes a variation of the FLAPS™ technology which allows operation over bandwidths in excess of 35% and makes it usable in broadband systems. Two new applications are feasible: one for a ground based telemetry system operating in the 1435-1850 or 1750-2400 MHz band and one for a shipboard satellite communication system operating in the 4000-6000 MHz band.

Balun is a key component in radio frequency (RF) circuits. The conventional Si-based planar spiral balun presented a high insertion loss. To solve this problem, this thesis firstly develops a Si-based suspending spiral balun using electrochemical deposition and surface micromachining technology for the fourth generation of wireless communication system. To reduce the power dissipation of the conventional Si-based planar spiral balun, thesis utilized a suspending structure to reduce the power loss through the substrate and dielectric layer. The fabricated suspending spiral balun are constructed by three bottom GSG electrodes, thirty three supporting copper vias and a suspending spiral copper conducting layer. The main fabrication processes in this research including: (1) four thin-film deposition processes, (2) four photolithography processes, (3) two etching processes and (4) two copper electroplating processes. In addition, this thesis used the commercial software (Ansoft HFSS) to analysis the high frequency characteristic of Si-based suspending spiral balun. The finished Si-based suspending spiral balun were measured by a commercial network analyzer under 2~8 GHz testing frequency range. Based on the measurement results, the value of insertion loss is 1.26 dB at 5.2 GHz, magnitude imbalanced is lower than 0.86 dB, phase imbalanced is less than 3.4 degree and CMRR is more than 30 dB. Finally, this thesis successfully develops a Si-based suspending spiral balun using MEMS technology for the fourth generation wireless communication system.

The objective of this study was to investigate the diversity of fireflies and the mating behavior of Luciola anceyi in Guanziling, Tainan. The field study was carried out from September 2010 to April 2012. The nocturnal survey of number of individuals and species of firefly was within one hour after sunset weekly in two transects, Jiulongshan 1 (JS1) and Shiya valley (SV). The diurnal firefly survey was from 2011 March to May once for every two weeks in these two transects. In addition, vegetation species and layers was recorded in these two transects during winter and spring. The sex ratio, population size and mating behavior of L. anceyi were studied in three transects (Jiulongshan 2, Jiulongshan 3 and Dadongshan) with mark-recapture and digital video camera. Total 6 genus and 14 species of firefly were found in JS1 and SV, Guanziling from September 2010 to December 2011. The maximum number of firefly species reached its peak of 8 in May and June in Guanziling, but no adult firefly was found in January, February and September. Four species of fireflies were found active during daytime, including Drilaster olivieri, Pyrocoelia formosana, Vesta scutellonigra and L. anceyi . The Shannon-Wiener¡¦s diversity index and evenness of nocturnal fireflies were both highest in summer, significantly higher than those from other seasons (Tukey's HSD, P¡Õ0.05). During spring and summer, 12 species of firefly species were recorded but only 4 species was recorded during autumn and winter. In 2011, Luciola cerata was the most dominant species in firefly community in Guanziling, accounted for 68.21%. The second comeon one was Luciola praeusta (9.48 %), followed by Luciola anceyi (6.42%), Curtos mundulus (5.92%), Diaphanes citrinus (4.47%), and Pyrocoelia praetexta (3.29%). The highest average density within one hour after sunset of L. cerata was from April to May (22.77/ 100 m2 and 15.54/ 100 m2 in JS1 and 6.07/ 100 m2 and 5.91/ 100 m2 in SV). The number of L. cerata was positively correlated with temperature in SV (P¡Õ0.05), but the number of L. anceyi was negatively correlated with relative humidity in SV (P¡Õ0.001). The number of L. praeusta was positively correlated with temperature of these two transects (P¡Õ0.05), and C. mundulus was positively correlated with temperature and relative humidity (P¡Õ0.05) in SV. But the number of D. citrinus and P. praetexta were neither correlated with temperature nor relative humidity from these two transects (P¡Ö0.05). Vegetation stratification in SV was more complex than in JS1, and firefly communities were influenced by plant stratification. The relative frequency of plant layer was the highest in two layers of shrub and herb (winter¡G31.82%¡Fspring¡G33.64%) and three layers of tree, shrub and herb (winter¡G30.91%¡Fspring¡G34.55%) among seven layers of plants in SV. On the other hand, The relative frequency was the highest in the single herb layer in JS1 (winter¡G47.50%¡Fspring¡G48.75 %), and lacking herb layer, two layers of tree and shrub and three layers of tree, shrub and herb. L. cerata prefers to appear in the grasslands of JS1, and D. citrinus and P. praetexta prefer to appear in the habitat with complex vegetation in SV. The courtship and copulation behavior of L. anceyi were recorded during daytime as well as nighttime. The number of adult male L. anceyi captured during daytime flying was significantly higher than adult female captured (P¡Õ0.05). During nighttime, the recapture rate of marked adult males of L. anceyi was twice that of adult females (15.94 % versus 8.55 %). It indicates that the adult L. anceyi appears to be active in the daytime and nighttime in the same area. The mating behavior of L. anceyi occurrs both day and night, therefore, male L. anceyi most likely uses chemical signals to find mates during day time. The mating pattern of L. anceyi is not corresponded with any sexual communication systems known for fireflies. Therefore it can be regarded as a new type of activity and sexual communication systems for fireflies. Although Guanziling area is influenced by long-term cultivation and over development, the quantity and species number of fireflies are plentiful and fireflies occur in all four seasons. Therefore Guanziling has the potential for developing ecotourism and firefly-watch. However, firefly-watch can also increase the damage to the environment. How to appropriately develop ecotourism without destroying the habitat may become the challenge and test for the goal of sustainable management. Finally, the results of this study can provide useful information for habitat conservation and management of fireflies in Guanziling.

This thesis comprises two topics : the first one is the design and implementation of FlexRay automotive communication system physical layer. The second part is the design of a high efficiency DC/DC Buck converter with sub-3 ¡Ñ VDD. The first topic discloses the physical layer design comprising the Bus Guardian and the Bus Driver used in an in-vehicle network compliant with FlexRay standards. It is realized in a mixed-signal chip using TSMC 1P6M 0.18 £gm CMOS process. Its core area is less than 0.8 mm2, and power consumption is less than 60 mW. The second topic is to design a DC to DC step-down converter, which can accommodate wide range VDD. By utilizing stacked power MOSFETs, a voltage level converter, a detector and a controller, the design is realized by a typical 1P6M 0.18 £gm CMOS process without any high voltage technology. The core area is less than 0.184 mm2, while the VDD range is up to 5 V. Since the internal reference voltage is 1 V, it can increase the output regulation range. The proposed design attains very high conversion efficiency to prolong the life time of power supply. Therefore, it can be integrated in a system chip to provide multiple supply voltage sources.

The iPad with the Proloquo2Go application has taken the world of autism by storm, and given individuals that do not have a voice, a voice. This study looks at the effectiveness of the iPad with the Proloquo2Go application to enhance the manding repertoire for children with autism. Participants included three children (2 girls and 1 boy) diagnosed with an autism spectrum disorder, or exhibiting characteristics of an autism spectrum disorder, between the ages of 3 and 5. A multiple probe design across participants was used to assess the effectiveness of the iPad. Methods included completing The Reinforcer Assessment for Individuals with Severe Disabilities (RAISD) with the parents and/or teachers of each participant and running a six stimuli preference assessment before implementing each Phase. Pretest probes were conducted before implementing Phases 1 through 4. These phases were comparable to Phases 1 through 4 of the Picture Exchange Communication System (PECS) (Bondy & Frost, 1994). Results of this study support that children with autism can acquire the skills needed to mand using the iPad with the Proloquo2Go application with training comparable to that of the Picture Exchange Communication System (Bondy & Frost, 1994). In addition, vocal requesting increased for the participants during the training phases in comparison to pretest probes.

Orbital Angular Momentum (OAM) modes promise an exciting future for communications due to the infinite number available and their orthogonal nature. However modern implementations of OAM mode communications utilize a multi-element approach to multiplexing. This multi-element approach wastes power and becomes increasingly complex and expensive as the number of modes in the system increases. This makes the multi-approach method not scalable. In this thesis we explore single element OAM multiplexing and de-multiplexing. A system utilizing single element multiplexer and de-multiplexer, was designed built and qualified. We have demonstrated that such a system can easily achieve a BER of less than 1% and is thusly feasible.

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The use of connected and autonomous ground and aerial vehicles is a promising solution to reduce accidents, improve the traffic efficiency, and provide various services ranging from delivery of goods to monitoring. Different from the current connected vehicles and autonomous vehicles, connected and autonomous vehicles (CAVs) combine autonomy and wireless connectivity and use both sensors and communication systems to increase their situational awareness and for their decision-making. However, in order to reap all the benefits of deploying CAVs, one must consider the interconnection between communication, control, and learning mechanisms for the CAV system design. The key goal of this dissertation is, thus, to develop foundational science that can be used for the design, analysis, and optimization of CAV systems while jointly taking into account the synergies among communication, control, and learning systems. First, a joint communication and control system design is developed for non-coordinated CAVs when performing autonomous path tracking. In particular, the maximum time delay requirements are derived to guarantee the stability of the controller when tracking two typical road scenarios (i.e., straight line and circular curve). Tools from optimization theory and risk theory are then used to jointly optimize the control system and power allocation for the communication network so as to maximize the number of vehicular links that meet the controller's delay requirements. Second, the joint control and communication design framework is extended to two coordinated CAVs applications, i.e., CAV platoons and unmanned aerial vehicle (UAV) swarms. Third, a distributed machine learning algorithm, i.e., federated learning (FL), is proposed for a swarm of connected and autonomous UAVs to execute tasks, such as coordinated trajectory planning and cooperative target recognition. In particular, a rigorous convergence analysis for FL is performed to show how wireless factors impact the FL convergence performance, and the design of UAV swarm networks is optimized to reduce the convergence time. Fourth, a new FL framework, called dynamic federated proximal (DFP) algorithm, is proposed for designing the autonomous controller of CAVs while considering the mobility of CAVs, the wireless fading channels, as well as the unbalanced and non independent and identically distributed data across CAVs. To improve the convergence of the proposed DFP algorithm, a contract-theoretic incentive mechanism is also proposed. Fifth, a wireless-enabled asynchronous federated learning (AFL) framework is proposed for urban air mobility (UAM) aircraft to collaboratively learn the turbulence prediction model. In particular, to characterize how UAM aircraft leverage wireless connectivity for AFL, a stochastic geometry based spatial model is developed and the wireless connectivity performance is analyzed. Then, a rigorous convergence analysis is performed for the proposed AFL framework to identify how fast the UAM aircraft converge to using the optimal turbulence prediction model. Sixth, based on the concordance order from stochastic ordering theory, a dependence control mechanism is proposed to improve the overall reliability of wireless networks for CAVs. Finally, to determine the optimal cache placement for CAVs, a novel spatio-temporal caching framework is proposed where the notion of graph motifs, i.e., the spatio-temporal communication patterns in wireless networks, is used. In conclusion, the frameworks presented in this dissertation will provide key fundamental guidelines to design, analyze, and optimize CAV systems. / Doctor of Philosophy / The evolution of transportation systems has always been the key to the progress of human societies. Recently, technology advances in sensing, autonomy, computing, and wireless connectivity ushered in the era of connected and autonomous vehicles (CAVs). In essence, CAVs rely on the data collected from sensors and wireless communication systems to automatically make the operation decision. If designed properly, the deployment of CAVs can improve the safety and the driving experience, increase the fuel efficiency and road capacity, as well as provide various services ranging from delivery of goods to monitoring. To reap all these benefits of deploying CAVs, one must address a number of technique challenges related to the wireless connectivity, autonomy, and autonomous learning for CAV systems. In particular, for CAV connectivity, the challenges include building a low latency and highly reliable network, using proper models for mobile radio channels, and determining the effective content dissemination strategy. At the control level, key considerations include guaranteeing stability and robustness for the controller when faced with measurement errors and wireless imperfections and rapidly adapting the CAV to dynamic environments. Meanwhile, when CAVs use machine learning to complete their tasks (e.g., object detection and environment monitoring), insufficient training data, privacy concerns, communication overhead, and limited energy are among the main challenges. Therefore, this dissertation develops the foundational science needed to design, analyze, and optimize CAVs while jointly taking into account the challenges within the wireless network, controller, and leaning mechanism design. To this end, various frameworks for the joint communication, control, and learning design and wireless network optimizations are proposed for different CAV applications. The results show that, using the proposed frameworks, the performance of CAVs can be optimized with more reliable communication systems, more stable controller, and improved learning mechanism, enabling intelligent transportation systems for the future smart cities.