12 research outputs found
Current Threats Of Rodents and Integrated Pest Management (IPM) for Stored Grain and Malting Barley
Synanthropic rodents belong to the worldwide dominant vertebrate pests occurring in agricultural and food industry environment. Rodents have enormous potential to cause multiple damages to human resources by feeding on crops and stored commodities and by their faecal and urine contamination. The latter is associated with a risk of transmission of pathogens into food and feed chain. In spite of its health and hygienic signifi cance the risk of faecal contamination of stored grain is often under-rated by store-keepers and farmers due to insuffi cient published summary information. Therefore in this overview, we summarised the relevant key-literature resources dealing with hazards associated with contamination of grain stores and food processing plants by rodents
Boolean Circuits, Tensor Ranks, And Communication Complexity
We investigate two methods for proving lower bounds on the size of small depth circuits, namely the approaches based on multiparty communication games and algebraic characterizations extending the concepts of the tensor rank and rigidity of matrices. Our methods are combinatorial, but we think that the main contribution concerns the algebraic concepts used in this area (tensor ranks and rigidity). Our main results are following. (i) An o(n) bit protocol for a communication game for computing shifts, which also gives an upper bound of o(n 2 ) on the contact rank of the tensor of multiplication of polynomials; this disproves some earlier conjectures. A related probabilistic construction gives o(n) upper bound for computing all permutations and O(n log log n) upper bound on the communication complexity of pointer jumping with permutations. (ii) A lower bound on certain restricted circuits of depth 2 which are related to the problem of proving a superlinear lower bound on the size of ..
Some constructive bounds on Ramsey numbers
AbstractWe present explicit constructions of three families of graphs that yield the following lower bounds on Ramsey numbers: R(4,m)⩾Ω(m8/5), R(5,m)⩾Ω(m5/3), R(6,m)⩾Ω(m2)
The complexity of proving that a graph is Ramsey
We say that a graph with n vertices is c-Ramsey if it does not contain either a clique or an independent set of size c log n. We define a CNF formula which expresses this property for a graph G. We show a superpolynomial lower bound on the length of resolution proofs that G is c-Ramsey, for every graph G. Our proof makes use of the fact that every Ramsey graph must contain a large subgraph with some of the statistical properties of the random graph
The complexity of proving that a graph is Ramsey
We say that a graph with n vertices is c-Ramsey if it does not contain either a clique or an independent set of size clogn. We define a CNF formula which expresses this property for a graph G. We show a superpolynomial lower bound on the length of resolution proofs that G is c-Ramsey, for every graph G. Our proof makes use of the fact that every Ramsey graph must contain a large subgraph with some of the statistical properties of the random graph