Jainendra K. Navlakha

Data-Driven Techniques in Disaster Information Management

Improving disaster management and recovery techniques is one of national priorities given the huge toll caused by man-made and nature calamities. Data-driven disaster management aims at applying advanced data collection and analysis technologies to achieve more effective and responsive disaster management, and has undergone considerable progress in the last decade. However, to the best of our knowledge, there is currently no work that both summarizes recent progress and suggests future directions for this emerging research area. To remedy this situation, we provide a systematic treatment of the recent developments in data-driven disaster management. Specifically, we first present a general overview of the requirements and system architectures of disaster management systems and then summarize state-of-the-art data-driven techniques that have been applied on improving situation awareness as well as in addressing users’ information needs in disaster management. We also discuss and categorize general data-mining and machine-learning techniques in disaster management. Finally, we recommend several research directions for further investigations.

Verification of programs with procedure-type parameters

SummaryA verification system is developed for proving the correctness of programs containing procedures with procedure-type parameters. The system, which reduces programs and their specifications to assertions to be proved in ordinary logic, is shown to be logically sound. The reduction process is controlled by the syntax of the program and is completely mechanical, requiring no human intervention. The resulting assertions involve higher-order predicates, but they engender no significant difficulties which are not already present in ordinary first-order theories.Our system views the intermediate objects in the reduction process as extended programs, thereby making verification a much less abstruse process. Treating logical assertions as commands appeals strongly to a programmers intuition.

Choosing a software cost estimation model for your organization: a case study

Abstract In the last decade or so, many software cost estimation models have been developed. These differ substantially from each other, particularly with respect to the inputs required and their outputs. For a software manager, the problem of selecting a particular model, or a combination of models that can be applied to an individual organization, is not all trivial. This paper describes our efforts to solve this problem for two organizations who had collected data on past development efforts. Statistical correlations between the actual and the estimated efforts calculated by using different cost estimation models were obtained. Regression analysis revealed that the cost model that is used by the organizations is not ideal for their environment. Statistical tests show that the results obtained are indeed statistically significant. The methodology used to perform the case study is applied to predict the development effort for a project, and the result is quite impressive.

Disaster SitRep - A vertical search engine and information analysis tool in disaster management domain

With the rise of heterogeneous information delivering platform, the process of collecting, integrating, and analyzing disaster related information from diverse channels becomes more difficult and challenging. Further, information from multiple sources brings up new challenges for information presentation. In this paper, we design and implement a Disaster Situation Reporting System (Disaster SitRep) that is essentially a disaster information collecting, integration, and presentation platform to address three critical tasks that can facilitate information acquisition, integration and presentation by utilizing domain knowledge as well as public and private web resources for major disaster recovery planning and management. Our proposed techniques create a disaster domain-specific search engine and a geographical information presentation and navigation platform using advanced data mining and information retrieval techniques for disaster preparedness and recovery that helps impacted communities better understand the current disaster situation. Specifically, hierarchical clustering with constraints are used to automatically update existing disaster concept hierarchy; taxonomy-based focused crawling component is developed to automatically detect, parse and filter those relevant web resources; a domain-oriented skeleton for each type of disasters is used to extract disaster events from disaster documents by defining the set of structural attributes. Furthermore, the platform can perform not only as a domain-specific search engine but also as an information monitoring and analysis tool for decision support during recovery phase of disasters.

An analytical technique for 3-dimensional interpolation

Given the values of a 3-dimensional function at unevenly spaced grid points on the grid structure of a channel, we describe a new analytical algorithm to determine the function value at an arbitrary point inside the channel. This algorithm has been implemented on a Univac 1100/81 computer in PL/I.

4×4 Tac-Tix is a second person game

4×4 Tac-Tix is a two person game with the last player losing. It had been conjectured for quite some time now that this was a second person game. By using the AND-OR trees and the grundy function technique extensively, we prove in this paper that both, the 4×4 Tac-Tix and its modified version are second person games.

A new proof technique to establish equivalence of the original and the generatedλ-free CFG with linear increase in size

To generate an equivalentλ-free context free grammar from an arbitrary CFG, the most efficient algorithms described in the literature increase the size of the grammar by a factor, polynomial in terms of the number of nonterminals maximally occuring on the right hand side of a production. In this paper, we present an algorithm to generate aλ-free CFG whose total space requirement (or its size) is limited to seven times the initial size. The correctness of our algorithm is established by using a new proof technique based on the structure of the derivation trees and using a counting argument to establish that if a terminal string can be derived in one grammar, it can also be derived in the other.

Symmetric solutions of the modified no-three-in-line problem for even boards

An algorithm for generating symmetric solutions of the modified no-three-in-line problem for the square boards of even size is presented. The correctness of the algorithm for arbitrarily large square boards is established. A computer program in PL/I was written and executed on the UNIVAC 1108 computer to generate the solutions for some boards of even size.