An Overview of the MySQL Engine and its Latest Features
Google engEDU
54 min – Apr 26, 2006

Google TechTalks
April 26, 2006

Timour Katchaounov

ABSTRACT
The first part of this talk describes the main principles behind MySQL’s query optimizer and execution engine, how the optimizer transforms queries into executable query plans, what these plans look like, and how they are executed.

The second part of the talk describes the major improvements in the query engine of MySQL 5.0, and how these improvements can benefit the users of MySQL 5.0. The "greedy" optimizer reduces compilation time for big queries with orders of magnitude. The "index merge" access method provides a way to use more than one index for the same query. For faster plan execution and to allow better join orders, the 5.0 optimizer transforms most outer joins into inner joins.

The outer joins that cannot be transformed into inner ones are executed in a pipeline manner, so that no intermediate results need to be materialized. Finally, some GROUP BY and DISTINCT queries can be executed much faster thanks to "loose index scan" technique that reads only a fraction of an index.

The talk concludes with the near-future plans for new features coming in the next versions of MySQL. Read the rest of this entry »

Internet Advertising and the Generalized Second Price Auction
Google engEDU
1 hr 3 min – Feb 9, 2006

Google TechTalks
February 9, 2006

Michael Schwarz

Michael Schwarz served as an Assistant Professor at Harvard Economics Department after earning a Ph.D. from Stanford Graduate School of Business. He is a member of the National Bureau of Economics Research. Dr. Schwarz specializes in economic theory and industrial organization and applications of theory to business decision making and public policy.

ABSTRACT
We investigate the "generalized second price" auction (GSP), a new mechanism which is used by search engines to sell online advertising that most Internet users encounter daily. GSP is tailored to its unique environment, and neither the mechanism nor the environment have previously been studied in the mechanism design literature. Although GSP looks similar to the Vickrey-Clarke-Groves (VCG) mechanism, its properties are very different. In particular, unlike the VCG mechanism, GSP generally does not have an equilibrium in dominant strategies, and truth-telling is not an equilibrium of GSP. To analyze the properties of GSP in a dynamic environment, we describe the generalized English auction that corresponds to the GSP and show that it has a unique equilibrium. This is an ex post equilibrium that results in the same payoffs to all players as the dominant strategy equilibrium of VCG. Read the rest of this entry »

Should Google Go Nuclear? Clean, cheap, nuclear power (no, really)
Google engEDU
1 hr 33 min – Nov 9, 2006

Google Tech Talks
November 9, 2006

ABSTRACT
This is not your father’s fusion reactor! Forget everything you know about conventional thinking on nuclear fusion: high-temperature plasmas, steam turbines, neutron radiation and even nuclear waste are a thing of the past. Goodbye thermonuclear fusion; hello inertial electrostatic confinement fusion (IEC), an old idea that’s been made new. While the international community debates the fate of the politically-turmoiled $12 billion ITER (an experimental thermonuclear reactor), simple IEC reactors are being built as high-school science fair projects.

Dr. Robert Bussard, former Asst. Director of the Atomic Energy Commission and founder of Energy Matter Conversion Corporation (EMC2), has spent 17 years perfecting IEC, a fusion process that converts hydrogen and boron directly into electricity producing helium as the only waste product. Most of this work was funded by the Department of Defense, the details of which have been under seal… until now.

Dr. Bussard will discuss his recent results and details of this potentially world-altering technology, whose conception dates back as far as 1924, and even includes a reactor design by Philo T. Farnsworth (inventor of the scanning television).

Can a 100 MW fusion reactor be built for less than Google’s annual electricity bill? Come see what’s possible when you think outside the thermonuclear box and ignore the herd. Read the rest of this entry »

Multiview Geometry for Texture Mapping 2D Images onto 3D Range Data
Google engEDU
46 min – Jun 29, 2006

Google TechTalks
June 29, 2006

George Wolberg

http://www-cs.engr.ccny.cuny.edu/~wolberg/

ABSTRACT
The photorealistic modeling of large-scale scenes, such as urban structures, requires a fusion of range sensing technology and traditional digital photography. In this talk, we describe a system that integrates multiview geometry and automated 3D registration techniques for texture mapping 2D images onto 3D range data. The 3D range scans and the 2D photographs are respectively used to generate a pair of 3D models of the scene. The first model consists of a dense 3D point cloud, produced by using a 3D-to-3D registration method that matches 3D lines in the range images. The second model consists of a sparse 3D point cloud, produced by applying a multiview geometry (structure-from-motion) algorithm directly on a sequence of 2D photographs.

This alignment is necessary to enable the photographs to be optimally texture mapped onto the dense model. The contribution of this work is that it merges the benefits of multiview geometry with automated registration of 3D range scans to produce photo-realistic models with minimal human interaction. We present results from experiments in large-scale urban scenes.

Joint with with Prof. Ioannis Stamos, Lingyun Liu, Gene Yu, and Siavash Zokai. Read the rest of this entry »

DSD: A Hybrid Analysis Tool for Bug Finding
Google engEDU
42 min – Jul 13, 2006

Google TechTalks
July 13, 2006

Christoph Csallner

ABSTRACT
DSD-Crasher is a bug finding tool that follows a three-step approach to program analysis: D. Capture the program’s intended execution behavior with dynamic invariant detection. The derived invariants exclude many unwanted values from the program’s input domain. S. Statically analyze the program within the restricted input domain to explore many paths. D. Automatically generate test cases that focus on verifying the results of the static analysis. Thereby confirmed results are never false positives, as opposed to the high false positive rate inherent in conservative static analysis.

This three-step approach yields benefits compared to past two-step combinations in the literature. In our evaluation with third-party applications, we demonstrate higher precision over tools that lack a dynamic step and higher efficiency over tools that lack a static step. Read the rest of this entry »