We study the complexity of approximately evaluating the Ising and Tutte partition functions with complex parameters. Our results are motivated by the study of the quantum complexity classes BQP and IQP. Recent results show how to encode quantum computations as evaluations of partition functions. These results rely on interesting and deep results about quantum computation in order to obtain hard...

In the present study, natural convective heat transfer in a partitioned square cavity utilizing nanofluids is studied. The vertical left and right walls are considered as the hot and cold walls, respectively and the partitions assumed to be adiabatic. The nanofluid used in this study is Al2O3 with the volume fraction of 20%. It is assumed that nanofluid is a single phase f...

Pulmonary gas uptake is a function of the blood solubility of a vapor, indicated by the blood/air partition coefficient. We hypothesized that blood lipid compositions are associated with the blood/air partition coefficients of lipophilic toxic vapors such as 1,3-butadiene. Our goal was to investigate cross-sectional and longitudinal relationships of blood triglycerides, total cholesterol, and a...

Document insertion into a native XML Data Store (XDS) requires to partition the document tree into a number of storage units with limited capacity, such as records on disk pages. As intra partition navigation is much faster than navigation between partitions, minimizing the number of partitions has a beneficial effect on query performance. We present a linear time algorithm to optimally partiti...

The partition problem concerns the partitioning of n given vectors in d-space into p parts, so as to maximize an objective function which is convex on the sum of vectors in each part. The problem has applications in diverse elds that include clustering, inventory, scheduling and statistical hypothesis testing. Since the objective function is convex, the partition problem can be reduced to the p...

We consider the problem of partitioning the set of vertices of a given unit disk graph (UDG) into a minimum number of cliques. The problem is NP-hard and various constant factor approximations are known, with the current best ratio of 3. Our main result is a polynomial time approximation scheme (PTAS) for this problem on UDG. In fact, we present a robust algorithm that given a graph G (not nece...

Atmospheric phase is the main factor affecting accuracy of ground-based synthetic aperture radar. The atmospheric screen (APS) may be very complicated, due to drastic changes in conditions, and conventional correction methods based on regression models cannot fit correct it effectively. Partition a feasible path improve (APC) for complicated APS, but overfitting problem ignored. In this article...