The pancake puzzle is a standard benchmark domain used to test search algorithms, and the gap heuristic is the stateof-the-art heuristic function most often used in such tests. In this work, we analyze the accuracy of this heuristic and identify ways to enhance it. We begin by showing that in the worst-case, the amount that the gap heuristic underestimates the optimal cost of a pancake puzzle s...

Wireless Sensor Networks (WSN) based on the IEEE 802.15.4 standard are constantly expanding. Applications like production control, building control are more and more based on WSN because of their energy efficiency, self organizing capacity and protocol flexibility. However, the construction of Cluster-Tree networks based on the beacon mode Pancake graphs is still undefined by the IEEE 802.15.4 ...

We simulate the impact of a viscous liquid drop onto a smooth dry solid surface. As in experiments, when ambient air effects are negligible, impact flattens the falling drop without producing a splash. The no-slip boundary condition at the wall produces a boundary layer inside the liquid. Later, the flattening surface of the drop traces out the boundary layer. As a result, the eventual shape of...

We use magnetic force microscopy to both image and manipulate individual vortex lines threading single crystalline YBa2Cu3O6.4, a layered superconductor. We find that when we pull the top of a pinned vortex, it may not tilt smoothly. Sometimes, we observe a vortex to break into discrete segments that can be described as short stacks of pancake vortices, similar to the “kinked” structure propose...

A 41-year-old man developed progressive bilateral hand weakness and spastic paraparesis. MRI demonstrated cord edema and “pancake-like” gadolinium enhancement (figure). Inflammatory/neoplastic causes were investigated and not found. He continued to deteriorate despite empiric corticosteroid treatment. One year later, cervical decompression stabilized his clinical condition but intramedullary T2...

We investigate experimentally the quenching of a liquid pancake, obtained through the impact of a water drop on a cold solid substrate (0 °C to -60 °C). We show that, below a certain substrate temperature, fractures appear on the frozen pancake and the crack patterns change from a 2D fragmentation regime to a hierarchical fracture regime as the thermal shock increases. The different regimes are...

Both the pancake graph and star graph are Cayley graphs and are especially attractive for parallel processing. They both have sublogarithmic diameter, and are fairly sparse compared to hypercubes. In this paper, we focus on another important property, namely the genus. The genus of a graph is the minimum number of handles needed for drawing the graph on the plane without edges crossing. We will...

The rural population in many parts of India consumes sorghum (Jowar) and maize as staple food. The flour made out of these cereals is consumed after cooking or baking on a pan with or without oil. The present study was undertaken in two groups of healthy human volunteers. Each subject of first group consumed ground unrefined sorghum (100g) daily as supper for three weeks in the form of pancake....

We use three-dimensional molecular dynamics simulations of magnetically interacting pancake vortices to study the dynamic phases of vortex lattices in highly anisotropic materials such as BSCCO. Our model treats the magnetic interactions of the pancakes exactly, with long-range logarithmic interactions both within and between planes. The pancake vortices decouple at low drives and show two-dime...