A symbol-based algorithm for decoding bar codes

We investigate the problem of decoding a bar code from a signal measured with a hand-held laser-based scanner. Rather than formulating the inverse problem as one of binary image reconstruction, we instead incorporate the symbology of the bar code into the reconstruction algorithm directly, and search for a sparse representation of the UPC bar code with respect to this known dictionary. Our approach significantly reduces the degrees of freedom in the problem, allowing for accurate reconstruction that is robust to noise and unknown parameters in the scanning device. We propose a greedy reconstruction algorithm and provide robust reconstruction guarantees. Numerical examples illustrate the insensitivity of our symbology-based reconstruction to both imprecise model parameters and noise on the scanned measurements.Comment: 24 pages, 12 figure

Multicompartment thermoresponsive gels: Does the length of the hydrophobic side group matter?

Multicompartment thermoresponsive gels are novel materials with fascinating self-assembly and interesting applications. The aim of this study was to investigate for the first time the effect of the length of the alkyl side group of a hydrophobic monomer on the thermoresponsive and self-assembly behaviour of terpolymers. Specifically twelve well-defined terpolymers based on the hydrophilic monomers 2-(dimethylamino)ethyl methacrylate (DMAEMA) and poly(ethylene glycol) methyl ether methacrylate (PEGMA), and on the hydrophobic monomer ethyl-, n-butyl or n-hexyl methacrylate (EtMA, BuMA or HMA) of varying architectures (ABC, ACB, BAC and statistical) were synthesised using Group Transfer Polymerisation. The A, B and C blocks were based on PEGMA, the alkyl containing methacrylate monomer, and DMAEMA, respectively. The molecular weights (MWs) and compositions of the polymers were kept the same. The polymers and their precursors were characterised in terms of their MWs, MW distributions and compositions. Aqueous solutions of the polymers were studied by turbidimetry, hydrogen ion titration, light scattering and rheology to determine their cloud points, pKas, hydrodynamic diameters and thermoresponsive behaviour and investigate the effect of the architecture and the hydrophobic alkyl side group of the terpolymers. It was found that the pKas and the Tgs were mostly affected by the hydrophobicity of the side groups and not by the architecture, while the cloud points and the sol-gel transition of the polymers were affected by both the length of the alkyl side group and the polymer architecture. Interestingly the sharpest sol-gel transitions and stable multicompartment hydrogels were observed for the ABC triblock copolymers with the short alkyl-side groups even though the sol-gel transition occurred at higher temperatures

Utilizing Ground-Based LIDAR Measurements to Aid Autonomous Airdrop Systems

Uncertainty in atmospheric winds represents one of the primary sources of landing error in airdrop systems. In this work, a ground-based LIDAR system samples the wind field at discrete points above the target and transmits real-time data to approaching autonomous airdrop systems. In simulation and experimentation, the inclusion of a light detection and ranging (LIDAR) system showed a maximum of 40% improvement over unaided autonomous airdrop systems. Wind information nearest ground level has the largest impact on improving accuracy

Deadly Discourse: Negotiating Bureaucratic Consensus for the Final Solution through Organizational and Technical Communication

The Final Solution was largely accomplished in eleven months; its executors, the Nazi SS, faced the constant problem that as killing and plunder escalated so did internal competition and corruption; and the SS deliberately cultivated an intensely competitive and polycratic organizational culture that fit the Nazi worldview of life-as-struggle. By tying these three observations together—that the Final Solution was punctuated, entropic, and polycratic—the problem arises: How did SS organizational communications manage, just barely long enough, to create a temporary social reality that regulated the internal contradictions of its genocidal project and fragmented bureaucracy? This study contends that through its organizational and technical communication—the outwardly normal and communally validated regime of formatted documents, official stationery, preprinted forms, filing codes, organizational nomenclature, and bureaucratic catchphrases—competing SS personnel found a common frame of reference to socially construct rules for temporary cooperation. Thus, their documents became boundary objects (Star & Griesemer, 1989; Wilson & Herndl, 2007) which bridged competing organizational interests within the rhetorical community (Miller, 1994) of desk-murderers. To explore this thesis an evidentiary sample of surviving documents is selected from a single but representative SS bureau, the Security Police (Sipo) Technical Matters Group that administered the mobile gas van program. The documents are analyzed according to Longo\u27s (1998) cultural research methodology for technical writing in which texts are examined in their historical and cultural contexts and then analyzed as discourse, followed by an interrogation of how the texts have been ordered by their analysts for purposes of study and the analysts\u27 relationships to the text. The organization of this project follows this methodology as Chapter 1 introduces the problem; Chapter 2 provides an historical narrative of the gas van program and its antecedents; Chapter 3 reviews the integrative aspects of the Group members\u27 national and institutional cultures, and the differentiating aspects of their organizational culture and its various subcultures; Chapter 4 describes the biographies and postwar testimonies of the Group\u27s principal actors; Chapter 5 introduces and describes the documents themselves; Chapter 6 offers an analysis, grounded in Miller\u27s (1994) concept of the rhetorical community, of the documents\u27 textual and visual rhetorics; Chapter 7 provides a discourse analysis of Group members\u27 use of linguistic resources; Chapter 8 explores various postwar orderings of the lengthiest and most notorious of the gas van texts, prior to and including Katz\u27s (1992a) introduction of the document into the technical communication literature; Chapter 9 interrogates how subsequent analysts within the discipline have ordered the text and what this may reveal about their relationships to it; and Chapter 10 elaborates possible implications for communication ethics. The research problem is answered with the claim that, rather than understanding the Final Solution only as the operation in extremis of Weberian bureaucratic rationality, the desk-murderers may be viewed as a rhetorical community that held chaos at bay through boundary objects—their documents—that deployed metaphors, narratives, and genres onto which competing interests could project their own interpretations while constructing temporary spaces of cooperation

“Knowledge Puffs Up”: The Evangelical Culture of Anti—Intellectualism as a Local Strategy

The anti-intellectual strain of American evangelicalism, rooted in the populist Great Awakenings of the 18th and 19th centuries, has prompted much commentary from the 20th century to the present. Analysis of this anti-intellectualism has gained new currency today as evangelicals, who comprise 1 in 4 Americans, reject theories of evolution and manmade climate change. Scholarship on the subject has focused on the discourses of evangelical leaders at the national level. The present study, based on three years of fieldwork at an evangelical church, finds that an animus against intellectual elites is a potent local strategy for constructing a satisfying evangelical identity within the organizational culture of a local congregation. Using a constant-comparative method, observations of more than fifty Sunday sermons, preached on the Gospel of Mark over 14 months, identified five binary themes. By spurning intellectualism, evangelicals can seek truth and avoid distraction, and be compassionate versus impersonal, inclusive versus pedantic, actors versus talkers, and God-seekers versus self-seekers. The five themes are then analyzed in terms of constructing an organizational identification in which casting intellectual elites as others is incorporated into church members\u27 personal and social identities. The study contributes to discussions of faith-based anti-intellectualism by demonstrating that macro-level discourses not only shape but also reflect micro-level practices