Data Mining - Concepts and Techniques.

An intelligent automated assistant system engages with the user in an integrated, conversational manner using natural language dialog, and invokes external services when appropriate to obtain information or perform various actions. The system can be implemented using any of a number of different platforms, such as the web, email, smartphone, and the like, or any combination thereof. In one embodiment, the system is based on sets of interrelated domains and tasks, and employs additional functionally powered by external services with which the system can interact.

Intelligent Automated Assistant

Semiconductor nanowires represent an important class of nanostructure building block for photovoltaics as well as direct solar-to-fuel application because of their high surface area, tunable bandgap and efficient charge transport and collection. In this talk, I will highlight several recent examples in this lab using semiconductor nanowires and their heterostructures for the purpose of solar energy harvesting. In addition, we have also discovered that the thermoconductivity of the silicon nanowires can be significantly reduced due to phonon scattering, pointing to a very promising approach to design better thermoelectrical materials. It is important to note that the engines that generate most of the world's power typically operate at only 30–40 per cent efficiency, releasing roughly 15 terawatts of heat to the environment. If this “wasted heat” could be recycled, the impact globally would be enormous. Our silicon nanowire thermoelectric technology could have a significant impact in alternative energy generation.

Semiconductor nanowires for energy conversion.

A virtual assistant uses context information to supplement natural language or gestural input from a user. Context helps to clarify the user's intent and to reduce the number of candidate interpretations of the user's input, and reduces the need for the user to provide excessive clarification input. Context can include any available information that is usable by the assistant to supplement explicit user input to constrain an information-processing problem and/or to personalize results. Context can be used to constrain solutions during various phases of processing, including, for example, speech recognition, natural language processing, task flow processing, and dialog generation.

Using context information to facilitate processing of commands in a virtual assistant

Materials engineering plays a key role in the field of energy storage. In particular, engineering materials at the nanoscale offers unique properties resulting in high performance electrodes and electrolytes in various energy storage devices. Consequently, considerable efforts have been made in recent years to fulfill the future requirements of electrochemical energy storage using these advanced materials. Various multi-functional hybrid nanostructured materials are currently being studied to improve energy and power densities of next generation storage devices. This review describes some of the recent progress in the synthesis of different types of hybrid nanostructures using template assisted and non-template based methods. The potential applications and recent research efforts to utilize these hybrid nanostructures to enhance the electrochemical energy storage properties of Li-ion battery and supercapacitor are discussed. This review also briefly outlines some of the recent progress and new approaches being explored in the techniques of fabrication of 3D battery structures using hybrid nanoarchitectures.

Hybrid Nanostructures for Energy Storage Applications

Since syntactically different URLs could represent the same resource in WWW, there are on-going efforts to define the URL normalization in the standard communities. This paper considers the three additional URL normalization steps beyond ones specified in the standard URL normalization. The idea behind our work is that in the URL normalization we want to minimize false negatives further while allowing false positives in a limited level. Two metrics are defined to analyze the effect of each step in the URL normalization. Over 170 million URLs that were collected in the real web pages, we did an experiment, and interesting statistical results are reported in this paper.

On URL normalization

The Google search site (http://www.google.com) exploits the link structure of the Web to measure the relative importance of Web pages. The ranking method implemented in Google is called PageRank [3]. The sum of all PageRank values should be one. However, we notice that the sum becomes less than one in some cases. We present an improved PageRank algorithm that computes the PageRank values of the Web pages correctly. Our algorithm works out well in any situations, and the sum of all PageRank values is always maintained to be one. We also present implementation issues of the improved algorithm. Experimental evaluation is carried out and the results are also discussed.

http://delab.csd.auth.gr/~dimitris/courses/ir_spring06/page_rank_computing/4u6x119wlwg6bp1p.pdf

An Improved Computation of the PageRank Algorithm

As web pages are created, destroyed, and updated dynamically, web databases should be frequently updated to keep web pages up-to-date. Understanding the change behavior of web pages certainly helps the administrators manage their web databases. This paper introduces a number of metrics representing various change behavior of the web pages. We have monitored approximately 1.8 million to three million URLs at two-day intervals for 100 days. Using the metrics we propose, we analyze the collected URLs and web pages. In addition, we propose a method that computes the probability that a page will be downloaded on the next crawls.

An empirical study on the change of web pages

An energy storage electrode system is fabricated via a template method with one-dimensional nanostructures that are hexagonally patterned in a honeycomblike fashion and vertically standing nanorods made of a gold-coated carbon nanotube core and a V2O5 shell layer. The performance of this system for Li insertion and extraction shows an increased capacity along with an enhanced rate performance, which could be attributed to the aligned nanostructures having increased reaction sites, facilitated charge transport, and improved stability in the face of mechanical stress.

Honeycomb pattern array of vertically standing core-shell nanorods: Its application to Li energy electrodes

This paper describes a new benchmark for object-relational DBMSs, the Benchmark for Object-Relational Databases (BORD). BORD has been developed to evaluate system performance peculiar to the object-relational data model as well as to the functions of modern database systems. The design philosophy, benchmark database, and test queries of the BORD benchmark are presented. BORD features scaleability, use of a synthesized database only, and a query-oriented evaluation. In total, thirty-six test queries have been designed under fifteen categories, which include exact matches, object identifiers, joins, class references, set-valued attributes, user-defined methods, built-in versus user-defined operators, flattening queries, generic abstract data types (ADTs), and spatial ADTs. In order to show the feasibility of the benchmark, we have implemented BORD with two commercial object-relational database systems. The experimental results are also reported.

Sang Ho Lee

Papers

On URL normalization

An Improved Computation of the PageRank Algorithm

An empirical study on the change of web pages

Honeycomb pattern array of vertically standing core-shell nanorods: Its application to Li energy electrodes

The BORD Benchmark for Object-Relational Databases