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A well-known theorem by Tarsi states that a minimally unsatisfiable CNF formula with m clauses can have at most m - 1 variables, and this bound is exact. In the context of proving lower bounds on proof space in k-DNF resolution, [Ben-Sasson and Nordström 2009] extended the concept of minimal unsatisfiability to sets of k-DNF formulas and proved that a minimally unsatisfiable k-DNF set with m formu

The aim of this paper is to show that logic programming is a powerful tool for representing scientific theories and for scientific inference. In a logic program it is possible to encode the qualitative and quantitative components of a theory in first order predicate logic, which is a highly expressive formal language. A theory program can then be handed to an algorithm that reasons about the theor

A combination of supercritical carbon dioxide (scCO2) impregnation of pyrrole and sonochemical transformation of permanganate (KMnO4) was used to impart conductive and catalytic properties to silk fibers. The results indicated that the conductivity (from polypyrrole –PPy) and catalytic activities (from manganese dioxide –MnO2) were independent and complementary within the processing parameters use

The mode of enquiry in African economic history has changed quite radically in recent years. In 1987, Patrick Manning surveyed practices and databases in African economic history and compared empirical strategies of scholars who studied the African past. Current practice, which A. G. Hopkins called “new African economic history,” incorporates econometric methods. The specific methods chosen and th

Semiconductor nanowires are widely considered as promising candidates for next generations of electronics and optoelectronics. Gold seed particles have so far been recognized as the most important catalyst for growth of nanowires. Costs related to substrates, lithography processes and gold consumption most strongly influence the final cost of nanowire-based devices. An optimum gold deposition proc

Due to rapid development of bacterial resistance against antibiotics, an emerging health crisis is underway, where ‘simple’ infections may no longer be treatable. Antimicrobial peptides (AMPs) constitute a class of substances attracting interest in this context. So far, research on AMPs has primarily focused on the identification of potent and selective peptides, as well as on the action mode of s

In cases of suspected scaphoid fracture where the initial radiographs are negative, a supplementary MRI, or alternatively CT, should be carried out within three to five days. Fracture classification, assessment of dislocation as well as evaluation of fracture healing is best done on CT with reconstructions in the coronal and sagittal planes, following the longitudinal axis of the scaphoid. After a

Prospects to use III-V technology to increase the performance of key millimeter wave circuits are discussed. We use 60 GHz wavelet generators to form coherent pulses with controllable pulse lengths down to 25 ps under low-power operation. The transmitters are used to demonstrate transmission at high data rates and very low bit-error-rates with simple modulation schemes (OOK) in direct links over s

Structural variants (SVs) rearrange large segments of DNA1 and can have profound consequences in evolution and human disease2,3. As national biobanks, disease-association studies, and clinical genetic testing have grown increasingly reliant on genome sequencing, population references such as the Genome Aggregation Database (gnomAD)4 have become integral in the interpretation of single-nucleotide v

In process industry many control loops are far from optimally tuned. In this master's thesis a tool for rapid process identification and control design has been developed. The tool, which is implemented in Matlab 5.3, identifies a process model out of the step response of the real process. A PI or PID controller can then be designed and evaluated. The tool contains three different automatic de

One problem when new controllers or control systems are built is the test of the controllers or the control systems. One way to test the controller is to build a real process to test the controller against. Another way to test the controller is to build the process-model in some kind of computer simulation tool. The advantages of using a simulation tool in a computer are quite many. For example

Efficient bioconversion of the pentose xylose is vital for the development of competent lignocellulose biorefineries. Although many proper attempts of metabolic engineering for recombinant xylose utilization have been made in Saccharomyces cerevisiae, growth on xylose is still far from being optimal. Previous findings point out a more complex explanation to this feature involving interactions betw