Computing observability don't cares efficiently through polarization

A new method is presented to compute the exact observability don't cares (ODCs) for multiple-level combinational circuits. A new mathematical concept, called polarization, is introduced. Polarization captures the essence of ODC calculation on the otherwise difficult points of reconvergence. It makes it possible to derive the ODC of a node from the ODCs of its fanouts with a very simple formula. Experimental results for the 39 largest MCNC benchmark examples show that the method is able to compute the ODC set (expressed as a Boolean network) for all but one circuit in at most a few second

A Minimum Cut Based Re-synthesis Approach

A new re-synthesis approach that benefits from min-cut based partitioning is proposed. This divide and conquer approach is shown to improve the performance of existing synthesis tools on a variety of benchmarks

Approximate logic circuits: Theory and applications

CMOS technology scaling, the process of shrinking transistor dimensions based on Moore's law, has been the thrust behind increasingly powerful integrated circuits for over half a century. As dimensions are scaled to few tens of nanometers, process and environmental variations can significantly alter transistor characteristics, thus degrading reliability and reducing performance gains in CMOS designs with technology scaling. Although design solutions proposed in recent years to improve reliability of CMOS designs are power-efficient, the performance penalty associated with these solutions further reduces performance gains with technology scaling, and hence these solutions are not well-suited for high-performance designs. This thesis proposes approximate logic circuits as a new logic synthesis paradigm for reliable, high-performance computing systems. Given a specification, an approximate logic circuit is functionally equivalent to the given specification for a "significant" portion of the input space, but has a smaller delay and power as compared to a circuit implementation of the original specification. This contributions of this thesis include (i) a general theory of approximation and efficient algorithms for automated synthesis of approximations for unrestricted random logic circuits, (ii) logic design solutions based on approximate circuits to improve reliability of designs with negligible performance penalty, and (iii) efficient decomposition algorithms based on approxiiii mate circuits to improve performance of designs during logic synthesis. This thesis concludes with other potential applications of approximate circuits and identifies. open problems in logic decomposition and approximate circuit synthesis

Financial Fragility and Economic Performance

Applied macroeconomists (e.g., Eckstein and Sinai (1986)) have stressed the role of financial variables, such as firm balance sheet positions, in the determination of investment spending and output. Our paper presents a formal analysis of this link. We develop a model of the process of investment finance in which there is asymmetric information between borrowers and lenders about the quality of investment projects and about the borrower's effort. In this model, the cost of external investment finance under the optimal contract is higher, the worse the borrower's balance sheet position (i.e., the lower his net worth). In general equilibrium, the lower is borrower net worth, the further the number of projects initiated and the average quality of undertaken projects will be from the unconstrained first-best. We characterize a "financially fragile" situation as one in which balance sheets are so weak that the economy experiences substantial underinvestment, misallocation of investment resources, and possibly even a complete investment collapse. Our policy analysis suggests that, under some circumstances, government "bailouts" of insolvent debtors may be a reasonable alternative in periods of extreme financial fragility.

Controllability Analysis and Control Design of Biological Systems Modeled by Boolean Networks

Cell signaling networks are often modeled using ordinary differential equations (ODEs), which represent network components with continuous variables. However, parameters such as reaction rate constants are needed for ODEs are not always available or known, and discrete approaches such as Boolean networks (BNs) are used in such cases. BNs have been applied in the past, in particular, as means to determine network steady states. The goal of this work is to explore the use of BNs from a control theory point of view, that to help manipulate biological systems more efficiently. In this thesis, we propose two methods to analyze and design control strategies for BNs. The first method, based on the algebraic state-space representation of BNs, consist of defining control strategies to reach predetermined states, namely, given a desired output, find all possible system state transition trajectories to that output, and design an input sequence leading to it. The second method aims at introducing an alternative and an extension of the first method in the sense that it offers broader possibilities for the representation of time and it is scalable to BNs of bigger size. This method is based on binary decision diagrams (BDDs), a data structure very efficient to represent logical functions and allow us to relate outputs of a network to its inputs no matter how many layers it contains and whether or not it has a cyclic structure

Controllability Analysis and Control Design of Biological Systems Modeled by Boolean Networks

Cell signaling networks are often modeled using ordinary differential equations (ODEs), which represent network components with continuous variables. However, parameters such as reaction rate constants are needed for ODEs are not always available or known, and discrete approaches such as Boolean networks (BNs) are used in such cases. BNs have been applied in the past, in particular, as means to determine network steady states. The goal of this work is to explore the use of BNs from a control theory point of view, that to help manipulate biological systems more efficiently. In this thesis, we propose two methods to analyze and design control strategies for BNs. The first method, based on the algebraic state-space representation of BNs, consist of defining control strategies to reach predetermined states, namely, given a desired output, find all possible system state transition trajectories to that output, and design an input sequence leading to it. The second method aims at introducing an alternative and an extension of the first method in the sense that it offers broader possibilities for the representation of time and it is scalable to BNs of bigger size. This method is based on binary decision diagrams (BDDs), a data structure very efficient to represent logical functions and allow us to relate outputs of a network to its inputs no matter how many layers it contains and whether or not it has a cyclic structure

Community Public-Private Partnership Leadership Synergy in Tanzania

Although the public-private partnership (PPP) concept in health and social health has been politically accepted as the best pathway to improving health outcomes in many developing nations, implementation lacks leadership synergy. Lack of awareness and engagement of community leaders about PPP interventions and their benefits affect accountability and ownership of health and social care interventions. The purpose of this study was to better understand factors that could promote partnership leadership synergy to enhance ownership and accountability for community health and social welfare initiatives in Tanzania. A qualitative empirical case study design was used; diffusion of innovation and the public-private integrated partnership module constituted the theoretical framework. A purposeful sample of 26 participants responded to in-depth, 1-on-1 interviews; they were guided with semi-structured questions; the related document was reviewed. NVivo software was used to facilitated data management and content analysis. The key findings indicated that integrated supportive supervision, teamwork, and strategic communications promote partnership leadership synergy. Also, findings show that a lack of clear roles and responsibilities, poor quality data, a lack of understanding the benefits of PPP in health at the community level hinder ownership and accountability in the implementation of PPP health interventions. The results of this study yield insight into the national PPP technical and leadership team that could support the priorities in the implementation of the partnership projects. These results may contribute to social change through an increase in awareness and understanding of PPP in health at the community level and, in turn, promote ownership and accountability

High Musical Achievement in Underserved High School Band Programs: A Qualitative Study

Although information is available detailing methods and strategies for high achievement in school band programs, very little is synthesized specifically addressing high schools in urban, inner-city, and other underserved student populations. This study explores the effects of cultural responsiveness, director-student relationships, and establishing and maintaining high standards on student motivation and overall program achievement. The data collected in this study originate from five Texas band directors in minority-majority programs where the school comprises a student population with over 60 percent eligibility for free and/or reduced lunch. These directors have all made significant achievements at the high school level in the state of Texas and have received recognition at the national level. For comparative purposes, all directors also maintain experience in the more affluent suburban situations. Furthermore, in most instances, the programs examined have shifted from being highly successful majority White suburban schools to now minority-majority urban program attempting to maintain or recapture past successes. These themes, while explicitly targeting urban/inner-city programs, are useful for band directors in all settings, as the strategies and methods examined may be effective in all high school band situations