Journal of Web Semantics special issue on HCI

January 15th, 2009

mc schraefel and Lloyd Rutledge are editing a special issue of the Journal of Web Semantics on “Exploring New Interaction Designs Made Possible by the Semantic Web“. The call for submissions described the topic this way.

“In this special issue of the Journal of Web Semantics we seek papers that look at the challenges and innovate possible solutions for everyday computer users to be able to produce, publish, integrate, represent and share, on demand, information from and to heterogeneous data sources. Challenges touch on interface designs to support end-user programming for discovery and manipulation of such sources, visualization and navigation approaches for capturing, gathering and displaying and annotating data from multiple sources, and user-oriented tools to support both data publication and data exchange. The common thread among accepted papers will be their focus on such user interaction designs/solutions oriented linked web of data challenges. Papers are expected to be motivated by a user focus and methods evaluated in terms of usability to support approaches pursued.”

In addition to full length research papers, they will also consider submissions of short (4-6 page) demonstration papers with evaluations of new tools that address any of the above challenges and brief (1-2 page) forward-looking, speculative papers addressing challenges. Submissions are due by 20 April 2009. Accepted papers are expected to appear online in preprint form in Summer 2009, online in final form by the end of 2009 and in print in 2010.

JWS special issue on Semantic Web and Policy (free sample issue)

January 13th, 2009

Elsevier has made the January 2009 Journal of Web Semantics special issue on the Semantic Web and Policy our new sample issue, which means that its paper are freely available online until a new sample issue is selected. The special issue editors, Lalana Kagal, Tim Berners-Lee and James Hendler wrote in the introduction:

“As Semantic Web technologies mature and become more accepted by researchers and developers alike, the widespread growth of the Semantic Web seems inevitable. However, this growth is currently hampered by the lack of well-defined security protocols and specifications. Though the Web does include fairly robust security mechanisms, they do not translate appropriately to the Semantic Web as they do not support autonomous machine access to data and resources and usually require some kind of human input. Also, the ease of retrieval and aggregation of distributed information made possible by the Semantic Web raises privacy questions as it is not always possible to prevent misuse of sensitive information. In order to realize it’s full potential as a powerful distributed model for publishing, utilizing, and extending information, it is important to develop security and privacy mechanisms for the Semantic Web. Policy frameworks built around machine-understandable policy languages, with their promise of flexibility, expressivity and automatable enforcement appear to be the obvious choice.

It is clear that these two technologies – Semantic Web and Policy – complement each other and together will give rise to security infrastructures that provide more flexible management, are able to accommodate heterogeneous information, have improved communication, and are able to dynamically adapt to variations in the environment. These infrastructures could be used for a wide spectrum of applications ranging from network management, quality of information, to security, privacy and trust. This special issue of the Journal of Web Semantics is focused on the impact of Semantic Web technologies on policy management, and the specification, analysis and application of these Semantic Web-based policy frameworks.”

In addition to the editors’ Introduction, the special issue includes five papers:

N. American Computational Linguistics Olympiad at UMBC

January 7th, 2009

If you are a high school or middle school student who is interested in
computers and also in languages, you should consider participating in the 2009 North American Computational Linguistics Olympiad (NACLO). This might be the first step on a path that could lead to your helping to create the next Google!

NACLO is a competition for middle-school and high-school students focused on solving problems involving linguistics and computational linguistics. WOrking the problems only requires keen analytical ability and good problem-solving skills — no prior background in linguistics, foreign languages or computer science is required.

NACLO consists of two rounds — an initial round on February 4 open to all students and a subsequent invitational round on March 11 for contestants who have advanced from the first. Winners of the second round will be invited to participate in the International Linguistics Olympiad. Last year, two US teams went to Bulgaria to compete in the sixth International Linguistics Olympiad and gold medals in individual and team events.

Support for NACLO is provided by Google, the Associaton for Computational Linguistics, and the National Science Foundation, which said in an August press release :

“Aside from being a fun intellectual challenge, the Olympiad mimics the skills used by researchers and scholars in the field of computational linguistics, which is increasingly important for the United States and other countries. Using computational linguistics, these experts can develop automated technologies such as translation software that cut down on the time and training needed to work with other languages, or software that automatically produces informative English summaries of documents in other languages or answer questions about information in these documents. In an increasingly global economy where businesses operate across borders and languages, having a strong pool of computational linguists is a competitive advantage. With threats emerging from different parts of the world, developing computational linguistics skills has also been identified as vital to national defense in the 21st century.” (src)

Students can participate at the NACLO site at UMBC, which is sponsored by the UMBC Institute for Language in Information Technology. Check out their poster and sample problem If you like this kind of puzzle and others like it, sign up to be part this exciting competition.

Students should register online by January 20. Late registrations may be accepted up to February 3 if space is available. The UMBC NACLO event will take place on Wednesday February 4 in room 312 of the University Center. For more information, contact one of the local organizers: Professors Marjorie McShane (, Sergei Nirenburg ( and Margaret A. Russell (

Macbook Wheel pushes HCI envelope

January 6th, 2009

The new Macbook Wheel is really pushing the Human Computer Interface envelope.

UMBC to host 2009 Global Game Jam site

January 6th, 2009

UMBC is hosting a site for the 2009 Global Game Jam on January 30-February 1, 2009. This is a two day game development contest sponsored by the International Game Developers Association and held simultaneously in 49 sites from 20 countries.

At 5pm local time on Friday, January 30, each site will be told the parameters of the game they all must produce. Participants pitch ideas, form teams, and get to work producing the best game they can in 48 hours. The UMBC site will have a good mix of computers and development platforms including Windows (XP), Mac (Leopard), XBox 360 (with Creators Club), PlayStation 3 (running Linux) with a diverse software environment that inlcludes Visual Studio, Maya, XNA Game Studio, NVIDIA PhysX and Adobe Creative Suite. For more information see the UMBC Global Game Jam page.

The Global Game Jam participants do not have to be UMBC students, and the Jam is open to participants of all levels of skill and experience. There is no registration fee for the Baltimore Jam site at UMBC, but space is limited so advance registration is required.

This event is sponsored by the UMBC Games, Animation and Interactive Media program, an innovative academic program with tracks available for students pursuing a degree in computer science or a degree in visual arts.

Ratsimor PhD: Bartering for goods and services in pervasive environments

January 5th, 2009

We’ve been working to get the dissertaions of our recent PhD graduates online. The latest one is Olga Ratsimor’s 2007 dissertation on bartering for goods and services in a mobile or pervasive environments. Here is the citation and abstract. You can click through on the title to get a pdf copy of the dissertation.

Olga Vladi Ratsimor, Opportunistic Bartering of Digital Goods and Services in Pervasive Environments, Ph.D. Dissertation in Computer Science, University of Maryland, Baltimore County, August 2007.

The vision of mobile personal devices querying peers in their environment for information such as local restaurant recommendations or directions to the closest gas station, or traffic and weather updates has long been a goal of the pervasive research community. However, considering the diversity and the personal nature of devices participating in pervasive environments it is not feasible to assume that these interactions and collaborations will take place with out economically-driven motivating incentives.

This dissertation presents a novel bartering communication model that provides an underlying framework for incentives for collaborations in mobile pervasive environments by supporting opportunistic serendipitous peer-to-peer bartering for digital goods such as ring tones, MP3’s and podcasts.

To demonstrate viability and advantages of this innovative bartering approach, we compare and contrast the performances of two conventional, frequently employed, peer-to-peer interaction approaches namely Altruists and FreeRiders against two collaborative strategies that employ the Double Coincidence of Wants paradigm from the domain of barter exchanges. In particular, we present our communication framework that represents these collaborative strategies through a set of interaction policies that reflect these strategies. Furthermore, we present a set of results from our in-depth simulation studies that compare these strategies.

We examine the operation of the nodes employing our framework and executing these four distinct strategies and specifically, we compare the performances of the nodes executing these strategies in homogeneous and heterogeneous networks of mobile devices. We also examine the effects of adding InfoStations to these networks. For each of the strategies, we observe levels of gains and losses that nodes experience as result of collaborative digital good exchanges. We also evaluate communication overhead that nodes incur while looking for possible collaborative exchange. Furthermore, this dissertation offers an in-depth study of the swarm-like inter-strategy dynamics in heterogeneous networks populated with diverse nodes displaying varying levels of collaborative interaction attitudes. Further, the bartering framework is extended by incorporating value-sensitive bartering models that incorporate digital goods and content valuations into the bartering exchange process. In addition, the bartering model is extended by integration of socially influenced collaborative interaction that exploit role based social relationships between mobile peers that populate dynamic mobile environments.

Taken as a whole, the novel research work presented in this dissertation offers the first comprehensive effort that employs and models opportunistic bartering-based collaborative methodology in the context of serendipitous encounters in dynamic mobile peer-to-peer pervasive environments where mobile entities negotiate and exchange digital goods and content.

DHS wants to mine social media for terrorism relatated data

January 5th, 2009

USA Today reports (Feds may mine blogs for terrorism clues) that the US Department of Homeland Security wants to use data-mining technology to search blogs and Internet message boards to find those used by terrorists to plan attacks.

“Blogging and message boards have played a substantial role in allowing communication among those who would do the United States harm,” DHS said in a recent notice.

Julian Sanchez notes on Ars Technica that the story is not new.

“The story is actually pegged to a Sources Sought Notice posted by the Department of Homeland Security back in October. Our colleagues at Wired reported on it at the time.”

Wenjia Li: Coping with Node Misbehaviors in MANETs, 4pm Tue 1/6/08, 325b ITE, UMBC

January 4th, 2009

Wenjia Li will present his dissertation proposal on ‘A Security Framework to Cope with Node Misbehaviors in Mobile Ad Hoc Networks’ which will be done under the supervision of Professor Anupam Joshi. The presentation will be at 4:00pm Tuesday, January 6, in ITE 325b. Here’s the abstract.

A Mobile Ad-hoc NETwork (MANET), as its name suggests, has no fixed infrastructure, and is generally composed of a dynamic set of cooperative peers, which are willing to share their wireless transmission power with other peers so that indirect communication can be possible between nodes that are not in the radio range of each other . The nature of MANETs, such as node mobility, unreliable transmission medium and restricted battery power, makes them extremely vulnerable to a variety of node misbehaviors. Wireless links, for instance, are generally prone to both passive eavesdropping and active intrusion. Another security concern in ad hoc networks is caused by the cooperative nature of the nodes. Attacks from external adversaries may disturb communications, but the external intruder generally cannot directly participate in the cooperative activities among the nodes, such as routing, because they do not possess the proper secure credentials, such as shared keys. However, compromised nodes, which are taken over by an adversary, are capable of presenting the proper secure credentials, and consequently can interfere with almost all of the network operations, such as route discovery, key management and distribution, and packet forwarding. Hence, it is essential to cope with node misbehaviors so as to secure mobile ad hoc networks.

In this dissertation, we address the question of how to ensure that a MANET will properly operate despite the presence of various node misbehaviors. We propose to build a framework that can cope with various node misbehaviors in a wise and adaptive manner. The main purpose of our proposed framework is to provide a platform so that the components that identify and respond to misbehaviors can better cooperate with each other and quickly adapt to the changes of network context. Therefore, policies are planned to be utilized in our framework in order to make those components correctly function in different network contexts. Besides the policy component, there are three other components, which fulfill the tasks of misbehavior detection, trust and reputation management, and route management, respectively. To validate and evaluate our proposed framework, we plan to implement our framework based on simulator.

In particular, the contributions of this dissertation are (i) Develop a framework to combine the functionalities of surveillance and detection of misbehavior, trust and reputation management, route management, and policy management so as to provide a high-level solution to cope with various misbehaviors in MANETs in an intelligent and adaptive manner (ii) Propose and implement a misbehavior detector based on the gossip-based outlier detection method, which relies on neither any pre-defined threshold nor any training data (iii) Take into account both first-hand information (direct observation) and second-hand information (indirect observation) during both misbehavior detection and trust management processes, in which first-hand information and second-hand information are merged by some intelligent methods (iv) Specify and enforce policies in the proposed framework, which makes the framework promptly adapt to the rapidly changing network context. quick and easy MapReduce for Python

January 2nd, 2009

The amount of free, interesting, and useful data is growing explosively. Luckily, computer are getting cheaper as we speak, they are all connected with a robust communication infrastructure, and software for analyzing data is better than ever. That’s why everyone is interested in easy to use frameworks like MapReduce for every-day programmers to run their data crunching in parallel. is a very simple MapReduce like system inspired by Ruby’s Starfish. doesn’t aim to meet all your distributed computing needs, but its simple approach is amendable to a large proportion of parallelizable tasks. If your code has a for-loop, there’s a good chance that you can make it distributed with just a few small changes. If you’re already using Python’s map() and reduce() functions, the changes needed are trivial!” is the simple example given in the documentation that is used with to compute the first 100 triangular numbers.

# compute first 100 triangular numbers. Do
# ' server' on server with address IP
# and ' client IP' on each client. Server uses source
# & final, sends tasks to clients, integrates results. Clients
# get tasks from server, use mapfn & reducefn, return results.

source = dict(zip(range(100), range(100)))

def final(key, value):
    print key, value

def mapfn(key, value):
    for i in range(value + 1):
        yield key, i

def reducefn(key, value):
    return sum(value)

Put on all of the machines you want to use. On the machine you will use as a server (with ip address <ip>), also install, and then execute:

     python server &

On each of your clients, run

     python client <ip> &

You can try this out using the same machine to run the server process and one or more client processes, of course.

When the clients register with the server, they will get a copy of and wait for tasks from the server. The server access the data from source and distributed tasks to the clients. These in turn use mapfn and reducefn to complete the tasks, returning the results. The server integrates these and, when all have completed, invokes final, which in this case just prints the answers, and halts. The clients continue to run, waiting for more tasks to do. is not a replacement for more sophisticated frameworks like Hadoop or Disco but if you are working in Python, its KISS approach is a good way to get started with the MapReduce paradigm and might be all you need for a small projects.

(Note: The package has not been updated since April 2008, so it’s status is not clear. But further development would run the risk of making it more complex and would be self-defeating.)