25083231
Meeting the challenge of software engineering education for working professionals in the 21st century
Software engineering education for working professionals remains a challenge from the perspective of determining relevant content; identifying effective methods for delivery; and maintaining the focus and motivation of students. This panel brings together academic and industry professionals to share their perspectives and experiences. Anticipated points for discussion include: education/training delivery strategies, curriculum definition, certification challenges, marketing issues, collaboration strategies to engage industry sponsorship, value assessments for students and sponsoring organizations, and program success stories. This will be a highly interactive panel and the audience should come prepared to both ask and answer questions.
11005034
Fostering software robustness in an increasingly hostile world
Software can kill. What are you doing to stay alive? Our world faces an increasingly hostile environment with challenges in complexity, technology, social engineering and clashing cultures. Failure to achieve sufficient software robustness can lead to customer dissatisfaction, financial loss, or in extreme cases -- loss of life. This panel brings together differing contexts and solution approaches.
41645329
The (Re) Emergence of Agile Languages and Domain-Oriented Programming
The JAOO conference in Aarhus, Denmark has become one of the most enjoyable and informative developer conferences in the land of OO. Originally a Java conference, it has expanded to cover a wide variety of topics from MS.NET and Java technology to best practices in software engineering. This year's conference followed on the heels of the Microsoft PDC earlier in the month. Both conferences featured tracks and sessions on scripting, dynamic languages and domain specific languages. There was also a Dynamic Languages Symposium Would any OO professional really consider using Basic when she has access to the full power of C#? Can MS really make it possible for disenfranchised Basic developers to have first class language access to XML, Databases and Objects with ease? Many at the PDC and JAOO were in shock as Erik Meijer (http://research.microsoft.com/~emeijer/) and the VB team showed off VB 9 features that combine clever type inference and structural sub-typing to simply and elegantly manipulate squares (relational tuples), circles (objects) and triangles (XML info sets) as simple polymorphic collections. Erik has also abandoned his solemn monadic oath of Haskell and quietly snuck some really interesting functional machinery under the hood of C#3.0 and VB 9 Erik is of course one of the key contributors to MS Zen and COmega (http://research.microsoft.com/COmega/) research efforts which are now bearing fruit in MS next language products under the name Language Integrated Query (LINQ – The LINQ team has really been thinking out of the box on this project and has made brave new efforts with very popular and widely used languages, which is always a great language design and implementation challenge.
2028674
An Exemplar Based Smalltalk
Two varieties of object-oriented systems exist: one based on classes as in Smalltalk and another based on exemplars (or prototypical objects) as in Act/1. By converting Smalltalk from a class based orientation to an exemplar base, independent instance hierarchies and class hierarchies can be provided. Decoupling the two hierarchies in this way enables the user's (logical) view of a data type to be separated from the implementer's (physical) view. It permits the instances of a class to have a representation totally different from the instances of a superclass. Additionally, it permits the notion of multiple representations to be provided without the need to introduce specialized classes for each representation. In the context of multiple inheritance, it leads to a novel view of inheritance (or-inheritance) that differentiates it from the more traditional multiple inheritance notions (and-inheritance). In general, we show that exemplar based systems are more powerful than class based systems. We also describe how an existing class based Smalltalk can be transformed into an exemplar-based Smalltalk and discuss possible approaches for the implementation of both and-inheritance and or-inheritance.
9882210
MDA: revenge of the modelers or UML utopia?
Modeling is at the core of many disciplines, but it is especially important in engineering because it facilitates communication and constructs complex things from smaller parts. Model engineering or model-driven development, treats software development as a set of transformations between successive models from requirements to analysis, to design, to implementation, to deployment. We discuss UML and MDA tools for developing software models. We also discuss domain specific languages, domain-oriented programming, platform-specific models and model engineering.
14393969
Programming with Models? Modeling with Code. The Role of Models in Software Development
In practice, engineers work with partial descriptions (models) and add/remove model elements at each level of abstraction. Models describe a slice of life – not life itself. Modelers use many different models to explore different aspects of the thing being modeled such as requirements, data, behavior, event/time, security, flow, process, activity, performance, quality, usability, etc. These models can take many forms and be expressed through many different tools including systems dynamics, prototypes, textual and visual models of artifacts and their relationships. It is important to note that UML is just one of many models representations which may be used in this process. The set of central relations in model-driven engineering and object-oriented technology are fundamentally different. The two central relations in object-oriented technology are isA and isPartOf. In model engineering the key relations are isBasedOn, isLike, and isRepresentedBy. These inherently one-to-many and partial relationships are often mistakenly confused with OOP relationships. Trying to use one set of relations, as a central interpretation, in the wrong context, can lead to serious problems. Models provide a representation of partial truths about the software system, but only the final code contains the actual truth.
5754219
Privacy preserving OLAP
We present techniques for privacy-preserving computation of multidimensional aggregates on data partitioned across multiple clients. Data from different clients is perturbed (randomized) in order to preserve privacy before it is integrated at the server. We develop formal notions of privacy obtained from data perturbation and show that our perturbation provides guarantees against privacy breaches. We develop and analyze algorithms for reconstructing counts of subcubes over perturbed data. We also evaluate the tradeoff between privacy guarantees and reconstruction accuracy and show the practicality of our approach.
5902879
Achieving anonymity via clustering
Publishing data for analysis from a table containing personal records, while maintaining individual privacy, is a problem of increasing importance today. The traditional approach of de-identifying records is to remove identifying fields such as social security number, name etc. However, recent research has shown that a large fraction of the US population can be identified using non-key attributes (called quasi-identifiers) such as date of birth, gender, and zip code [15]. Sweeney [16] proposed the k-anonymity model for privacy where non-key attributes that leak information are suppressed or generalized so that, for every record in the modified table, there are at least k−1 other records having exactly the same values for quasi-identifiers. We propose a new method for anonymizing data records, where quasi-identifiers of data records are first clustered and then cluster centers are published. To ensure privacy of the data records, we impose the constraint that each cluster must contain no fewer than a pre-specified number of data records. This technique is more general since we have a much larger choice for cluster centers than k-Anonymity. In many cases, it lets us release a lot more information without compromising privacy. We also provide constant-factor approximation algorithms to come up with such a clustering. This is the first set of algorithms for the anonymization problem where the performance is independent of the anonymity parameter k. We further observe that a few outlier points can significantly increase the cost of anonymization. Hence, we extend our algorithms to allow an ε fraction of points to remain unclustered, i.e., deleted from the anonymized publication. Thus, by not releasing a small fraction of the database records, we can ensure that the data published for analysis has less distortion and hence is more useful. Our approximation algorithms for new clustering objectives are of independent interest and could be applicable in other clustering scenarios as well.
45241819
Minimum Networks in Uniform Orientation Metrics
In this paper we use the variational method to systematically study properties of minimum networks connecting any given set of points (called terminals) in a $\lambda$-plane, in which all lines are in $\lambda$ uniform orientations $i\pi /\lambda\ (0\le i<\lambda )$. We prove a number of angle conditions for Steiner minimum $\lambda$-trees, which are similar to the ones in the Euclidean case. In particular, we show that there exists a Steiner minimum $\lambda$-tree whose minimum angles at Steiner points are $\lfloor 2\lambda /3\rfloor\pi /\lambda$ and whose maximum angles are $\lceil 2\lambda /3\rceil\pi /\lambda$. We also investigate the assignment of nonstraight edges and unequal angles in Steiner minimum $\lambda$-trees, and we prove that there exists a Steiner minimum $\lambda$-tree in which every full component has at most one nonstraight edge. From these properties we are able to devise a number of finite methods for constructing Steiner minimum $\lambda$-trees. One of these methods is based on using algorithms for finding graphical Steiner minimum trees, and the other uses a generalization of the method of Melzak for Euclidean Steiner trees.
45579896
Full Minimal Steiner Trees on Lattice Sets
Given a finite set of points P in the Euclidean plane, the Steiner problem asks us to constuct a shortest possible network interconnecting P. Such a network is known as a minimal Steiner tree. The Steiner problem is an intrinsically difficult one, having been shown to be NP-hard [7]; however, it often proves far more tractable if we restrict our attention to points in special geometric configurations. One such restriction which has generated considerable interest is that of finding minimal Steiner trees for nice sets of integer lattice points. The first significant result in this direction was that of Chung and Graham [4], which, in effect, precisely characterized the minimal Steiner trees for any horizontal 2_n array of integer lattice points. In 1989, Chung et al. [3] examined a related problem, which they described as the Checkerboard Problem. They asked how to find a minimal Steiner tree for an n_n square lattice, that is, a collection of n_n points arranged in a regular lattice of unit squares like the corners of the cells of article no. TA962752
15059814
Caching queues in memory buffers
Motivated by the need for maintaining multiple, large queues of data in modern high-performance systems, we study the problem of caching queues in memory under the following simple, but widely applicable, model. At each clock-tick, any number of data items may enter the various queues, while data-items are consumed from the heads of the queues. Since the number of unconsumed items may exceed memory buffer size, some items in the queues need to be spilled to secondary storage and later moved back into memory for consumption. We provide online queue-caching algorithms under a number of interesting cost models.