On finitely ambiguous B\"uchi automata

Unambiguous B\"uchi automata, i.e. B\"uchi automata allowing only one accepting run per word, are a useful restriction of B\"uchi automata that is well-suited for probabilistic model-checking. In this paper we propose a more permissive variant, namely finitely ambiguous B\"uchi automata, a generalisation where each word has at most $k$ accepting runs, for some fixed $k$. We adapt existing notions and results concerning finite and bounded ambiguity of finite automata to the setting of $\omega$-languages and present a translation from arbitrary nondeterministic B\"uchi automata with $n$ states to finitely ambiguous automata with at most $3^n$ states and at most $n$ accepting runs per word

Migratory winter bag-net fishery in coastal waters of the Hooghly estuary

The migratory winter big-net fishery is a typical feature of the coastal waters of the Hooghly estuary, 4,000 man with about 800 bag-nets migrated from different estuarine areas and established fishing camps In different islands during 1934 85 and 1985-86. Three and a half months seasonal fishery accounted for an average estimated fish yield of 17,872 t, forming about 71% of the total fish yield from the estuary as against 29% to 33% about 15 year* ago. An average catch per unit of effort of 152 kg was about 18 to 36 times that obtained in the upper and middle stretches and about 3 times more than that 15 years ago in the lower coastal waters. Harpodon nehereus, Trichlurus spp., Psma pama, Setipinna spp. and different species of prawns dominated in the catches. The bulk of the catches are tundrlsd and exported to marketing centres. The reasons for tremendous increase in the winter migratory bag-net catches have been discusse

Random Costs in Combinatorial Optimization

The random cost problem is the problem of finding the minimum in an exponentially long list of random numbers. By definition, this problem cannot be solved faster than by exhaustive search. It is shown that a classical NP-hard optimization problem, number partitioning, is essentially equivalent to the random cost problem. This explains the bad performance of heuristic approaches to the number partitioning problem and allows us to calculate the probability distributions of the optimum and sub-optimum costs.Comment: 4 pages, Revtex, 2 figures (eps), submitted to PR

Recipients of electric-powered indoor/outdoor wheelchairs provided by a National Health Service: A cross-sectional study

This is the post-print version of the final paper published in Archives of Physical Medicine and Rehabilitation. The published article is available from the link below. Changes resulting from the publishing process, such as peer review, editing, corrections, structural formatting, and other quality control mechanisms may not be reflected in this document. Changes may have been made to this work since it was submitted for publication. Copyright @ 2013 by the American Congress of Rehabilitation Medicine.OBJECTIVE: To describe the characteristics, across all ages, of powered wheelchair users and the assistive technology prescribed by a regional specialist wheelchair service DESIGN: Cross-sectional study SETTING: Regional wheelchair service provided to those fulfilling strict eligibility criteria by a National Health Service serving a population of 3 million. PARTICIPANTS: 544 Electric Powered Indoor/outdoor wheelchair (EPIOC) users. INTERVENTIONS: Not applicable MAIN OUTCOME MEASURES: Demographic, clinical/diagnostic details of EPIOC recipients including pain, (kypho)scoliosis and ventilators. Technical features including specialised (adaptive) seating (SS), tilt in space (TIS), and modified control systems. Factors were related to age groups: 1 (0-15), 2 (16-24), 3 (25-54), 4 (55-74) and 5 (75+). RESULTS: 262 men mean age 41.7 (range 8-82, sd 20.7) and 282 women mean age 47.2 (range 7-92, sd 19.7) years were studied. Neurological/neuromuscular conditions predominated (81%) with cerebral palsy (CP) (18.9%) and multiple sclerosis (16.4%). Conditions presenting at birth or during childhood constituted 39%. 99 had problematic pain, 83 a (kypho)scoliosis and 11 used ventilators. SS was provided to 169 users (31%), the majority had CP or muscular dystrophy. TIS was used by 258 (53%). Younger people were more likely to receive TIS than older ones. Only 92 had SS and TIS, mean age 29 (range 8-72, sd 17.8) years. 52 used modified control systems. CONCLUSIONS: The diversity of EPIOC users across age and diagnostic groups is shown. Their complex interrelationships with these technical features of EPIOC prescription are explored. Younger users were more complex due to age-related changes. This study provides outcomes of the EPIOC prescription for this heterogeneous group of very severely disabled people

Bounds on the Complexity of Halfspace Intersections when the Bounded Faces have Small Dimension

We study the combinatorial complexity of D-dimensional polyhedra defined as the intersection of n halfspaces, with the property that the highest dimension of any bounded face is much smaller than D. We show that, if d is the maximum dimension of a bounded face, then the number of vertices of the polyhedron is O(n^d) and the total number of bounded faces of the polyhedron is O(n^d^2). For inputs in general position the number of bounded faces is O(n^d). For any fixed d, we show how to compute the set of all vertices, how to determine the maximum dimension of a bounded face of the polyhedron, and how to compute the set of bounded faces in polynomial time, by solving a polynomial number of linear programs

Analysis of the intraspinal calcium dynamics and its implications on the plasticity of spiking neurons

The influx of calcium ions into the dendritic spines through the N-metyl-D-aspartate (NMDA) channels is believed to be the primary trigger for various forms of synaptic plasticity. In this paper, the authors calculate analytically the mean values of the calcium transients elicited by a spiking neuron undergoing a simple model of ionic currents and back-propagating action potentials. The relative variability of these transients, due to the stochastic nature of synaptic transmission, is further considered using a simple Markov model of NMDA receptos. One finds that both the mean value and the variability depend on the timing between pre- and postsynaptic action-potentials. These results could have implications on the expected form of synaptic-plasticity curve and can form a basis for a unified theory of spike time-dependent, and rate based plasticity.Comment: 14 pages, 10 figures. A few changes in section IV and addition of a new figur

Efficacy and Tolerability of Intramuscular Dexketoprofen in Postoperative Pain Management following Hernia Repair Surgery

Objective. To evaluate the safety and efficacy of intramuscular dexketoprofen for postoperative pain in patients undergoing hernia surgery. Methodology. Total 202 patients received single intramuscular injection of dexketoprofen 50 mg or diclofenac 50 mg postoperatively. The pain intensity (PI) was self-evaluated by patients on VAS at baseline 1, 2, 4, 6, and 8 hours. The efficacy parameters were number of responders, difference in PI (PID) at 8 hours, sum of analogue of pain intensity differences (SAPID), and onset and duration of analgesia. Tolerability assessment was done by global evaluation and adverse events in each group. Results. Dexketoprofen showed superior efficacy in terms of number of responders (P = .007), PID at 8 hours (P = .02), and SAPID 0–8 hours (P < .0001). It also showed faster onset of action (42 minutes) and longer duration of action (6.5 hours). The adverse events were comparable in both groups. Conclusion. Single dose of dexketoprofen trometamol 50 mg given intramuscularly provided faster, better, and longer duration of analgesia in postoperative patients of hernia repair surgery than diclofenac 50 mg, with comparable safety

Analysis of the Karmarkar-Karp Differencing Algorithm

The Karmarkar-Karp differencing algorithm is the best known polynomial time heuristic for the number partitioning problem, fundamental in both theoretical computer science and statistical physics. We analyze the performance of the differencing algorithm on random instances by mapping it to a nonlinear rate equation. Our analysis reveals strong finite size effects that explain why the precise asymptotics of the differencing solution is hard to establish by simulations. The asymptotic series emerging from the rate equation satisfies all known bounds on the Karmarkar-Karp algorithm and projects a scaling $n^{-c\ln n}$, where $c=1/(2\ln2)=0.7213...$. Our calculations reveal subtle relations between the algorithm and Fibonacci-like sequences, and we establish an explicit identity to that effect.Comment: 9 pages, 8 figures; minor change

Knowledge-based energy functions for computational studies of proteins

This chapter discusses theoretical framework and methods for developing knowledge-based potential functions essential for protein structure prediction, protein-protein interaction, and protein sequence design. We discuss in some details about the Miyazawa-Jernigan contact statistical potential, distance-dependent statistical potentials, as well as geometric statistical potentials. We also describe a geometric model for developing both linear and non-linear potential functions by optimization. Applications of knowledge-based potential functions in protein-decoy discrimination, in protein-protein interactions, and in protein design are then described. Several issues of knowledge-based potential functions are finally discussed.Comment: 57 pages, 6 figures. To be published in a book by Springe