Network Interface Design for Network-on-Chip

In the culture of globalized integrated circuit (IC, a.k.a chip) production, the use of Intellectual Property (IP) cores, computer aided design tools (CAD) and testing services from un-trusted vendors are prevalent to reduce the time to market. Unfortunately, the globalized business model potentially creates opportunities for hardware tampering and modification from adversary, and this tampering is known as hardware Trojan (HT). Network-on-chip (NoC) has emerged as an efficient on-chip communication infrastructure. In this work, the security aspects of NoC network interface (NI), one of the most critical components in NoC will be investigated and presented. Particularly, the NI design, hardware attack models and countermeasures for NI in a NoC system are explored. An OCP compatible NI is implemented in an IBM0.18ìm CMOS technology. The synthesis results are presented and compared with existing literature. Second, comprehensive hardware attack models targeted for NI are presented from system level to circuit level. The impact of hardware Trojans on NoC functionality and performance are evaluated. Finally, a countermeasure method is proposed to address the hardware attacks in NIs

Heterogeneous Integration on Silicon-Interconnect Fabric using fine-pitch interconnects (≤10 �m)

Today, the ever-growing data-bandwidth demand is pushing the boundaries of the traditional printed circuit board (PCB) based integration schemes. Moreover, with the apparent saturation of semiconductor scaling, commonly called Moore's law, system scaling warrants a paradigm shift in packaging technologies, assembly techniques, and integration methodologies. In this work, a superior alternative to PCBs called the Silicon-Interconnect Fabric (Si-IF) is investigated. The Si-IF is a silicon-based, package-less, fine-pitch, highly scalable, heterogeneous integration platform for wafer-scale systems. In this technology, unpackaged dielets are assembled on the Si-IF at small inter-dielet spacings (≤100 �m) using fine-pitch (≤10 �m) die-to-substrate interconnects. A novel assembly process using a solder-less direct metal-metal (gold-gold and copper-copper) thermal compression bonding was developed. Using this process, sub-10 �m pitch interconnects with a low specific contact resistance of ≤0.7 Ω-�m2 were successfully demonstrated. Because of the tightly packed Si-IF assembly, the communication links between the neighboring dies are short (≤500 �m) with low loss (≤2 dB), comparable to on-chip connections. Consequently, simple buffers can transfer data between dies using a Simple Universal Parallel intERface for chips (SuperCHIPS) at low latency (<30 ps), low energy per bit (≤0.03 pJ/b), and high data-rates (up to 10 Gbps/link), corresponding to an aggregate bandwidth up to 8 Tbps/mm. The benefits of the SuperCHIPS protocol were experimentally demonstrated to provide 5-90X higher data-bandwidth, 8-30X lower latency, and 5-40X lower energy per bit compared to existing integration schemes. This dissertation addresses the assembly technology and communication protocols of the Si-IF technology

Application of advanced on-board processing concepts to future satellite communications systems: Bibliography

Abstracts are presented of a literature survey of reports concerning the application of signal processing concepts. Approximately 300 references are included

Neural Mechanisms that Control an Innate Foraging Behavior in Caenorhabditis Elegans

The ability to efficiently locate food is critical for survival. Thus, animals modify their foraging patterns based on recent experience and current conditions to increase their likelihood of finding food. One highly conserved foraging strategy is local search, an intensive exploration over several minutes of the region where food resources were last encountered. As time since the last food encounter passes, animals transition to global search strategies to explore distant areas. The local-to-global search foraging pattern has been observed in fish, reptiles, insects, birds, and mammals, yet few studies ask how an animal’s brain generates this ancient behavior. Here, I ask this question in the nematode Caenorhabditis elegans. In Chapter 1, I characterize the behavior in wildtype animals and find that local search is a food memory that is regulated by food history and by internal satiety states. In addition, I describe the behavior in individual animals and find that although the behavior is reliable at a population level, there is large variability between individuals. In Chapter 2, I conduct a candidate genetic screen to first find a gene important for local search, and then define a circuit for local search behavior. The circuit consists of two parallel multimodal circuit modules that control local search. In each module, chemosensory or mechanosensory glutamatergic neurons that detect food-related cues trigger local search by inhibiting separate integrating neurons through a metabotropic glutamate receptor, MGL-1. The chemosensory and mechanosensory modules are separate and redundant, as glutamate release from either can drive the full behavior. In addition, the ability of the sensory modules to control local search is gated by the internal nutritional state of the animal. In Chapter 3, I characterize neuronal activity within the chemosensory module. Spontaneous activity patterns in the chemosensory module encode information about the time since the last food encounter and correlate with the foraging behavior. Glutamate acts within the module to shape activity patterns at various time scales. Taken together, these experiments reveal a circuit configuration that allows for the robust control of an innate adaptive behavior

Characterizing biological systems: quantitative methods for synthetic genetic circuits in plants and intracellular mechanics

2018 Summer.Includes bibliographical references.To view the abstract, please see the full text of the document

OPTOGENETIC GUIDE RNA PRODUCTION FOR SPATIOTEMPORAL REGULATION OF CRISPR/CAS SYSTEMS

OPTOGENETIC GUIDE RNA PRODUCTION FOR SPATIOTEMPORAL REGULATION OF CRISPR/CAS SYSTEM

A Polymorphic Microdeletion in the RGS9 Gene Suppresses PTB Binding and Associates with Obesity

Objective: RGS9 is a member of the family of Regulators of G-Protein Signaling (RGS) proteins defined by the presence of an RGS domain which can accelerate the GTPase-activity of G protein Gα subunits. An insertion/deletion (I/D) polymorphism of the nucleotide sequence TTTCT (rs3215227) has been identified in the human RGS9 gene, which matches the consensus high affinity binding motif for the ubiquitously expressed RNA binding Polypyrimidine Tract Binding Protein (PTB). In this study, we evaluate the genetic association and functional relevance of this polymorphism in type 2 diabetes and obesity. Subjects and methods: We genotyped a larger population of 9272 Chinese and Malaysian individuals for the RGS9 I/D polymorphism using TaqMan allelic discrimination protocols. We found that the D allele of the RGS9 polymorphism was associated with a decreased prevalence of obesity in women (P=0.003, OR=0.753 95%CI 0.625-0.906) and girls (P=0.002, OR=0.604 95%CI 0.437-0.835). The association was moderate in boys (P=0.038, OR=0.724 95%CI 0.533-0.983) and not significant in men. Furthermore, we found that the transcript deletion variant exhibited a 10-fold reduction in PTB binding in vitro and that the splicing of the deletion variant was less affected by PTB co-expression. Conclusions: We provide genetic and biochemical data to support a genetic role of RGS9 in obesity but unlikely in T2D. The RGS9 I/D polymorphism influence the post-transcriptional processing of the gene through an altered affinity for the splicing factor PTB and are associated with obesity

Asynchronous design of a multi-dimensional logarithmic number system processor for digital hearing instruments.

This thesis presents an asynchronous Multi-Dimensional Logarithmic Number System (MDLNS) processor that exhibits very low power dissipation. The target application is for a hearing instrument DSP. The MDLNS is a newly developed number system that has the advantage of reducing hardware complexity compared to the classical Logarithmic Number System (LNS). A synchronous implementation of a 2-digit 2DLNS filterbank, using the MDLNS to construct a FIR filterbank, has successfully proved that this novel number representation can benefit this digital hearing instrument application in the requirement of small size and low power. In this thesis we demonstrate that the combination of using the MDLNS, along with an asynchronous design methodology, produces impressive power savings compared to the previous synchronous design. A 4-phase bundled-data full-handshaking protocol is applied to the asynchronous control design. We adopt the Differential Cascade Voltage Switch Logic (DCVSL) circuit family for the design of the computation cells in this asynchronous MDLNS processor. Besides the asynchronous design methodology, we also use finite ring calculations to reduce adder bit-width to provide improvements compared to the previous MDLNS filterbank architecture. Spectre power simulation results from simulations of this asynchronous MDLNS processor demonstrate that over 70 percent power savings have been achieved compared to the synchronous design. This full-custom asynchronous MDLNS processor has been submitted for fabrication in the TSMC 0.18mum CMOS technology. A further contribution in this thesis is the development of a novel synchronizing method of design for testability (DfT), which is offered as a possible solution for asynchronous DfT methods.Dept. of Electrical and Computer Engineering. Paper copy at Leddy Library: Theses & Major Papers - Basement, West Bldg. / Call Number: Thesis2004 .W85. Source: Masters Abstracts International, Volume: 43-01, page: 0288. Advisers: G. A. Jullien; W. C. Miller. Thesis (M.A.Sc.)--University of Windsor (Canada), 2004