Quality enhancements of digital outline fonts

Digital fonts are easily available today and their use has become widespread. Nevertheless, the visual quality of printed and displayed text and the technical quality of digital typefaces are often unsatisfactory. The foremost reason for this situation is that font manufacturing systems manipulate font representations through low-level operations. In this paper we examine several aspects of font quality, and present a method for enhancing the quality of a typeface given in today's standard representation, the outline (boundary) representation. The method is based on the usage of high-level typographic features, and includes enhancements to both individual glyphs and complete fonts. Glyph enhancements include elimination of redundant points, insertion of essential points, corrections to contour orientations and inter-penetrations, and vertical and horizontal coherence. Font enhancements include regularization of font weights and sizes, serif unification, and feature extraction and discrimination. Our method is comprised of several algorithms that have been implemented in a commercial font manufacturing system, achieving enhanced quality of the fonts produced.     

Incentive Compatible Pricing Strategies for QoS Routing

QoS routing mechanisms allow users identify paths that can accommodate their performance requirements and reserve the necessary resources. An important problem is how to conduct such resource allocation efficiently, not only from the single-connection, but also from the network point of view. We propose the use of pricing mechanisms as a means to regulate the users' decisions in a networkwide efficient manner. Focusing on QoS architectures that employ rate-based schedulers, we formulate a congestion-based pricing scheme. We establish the structure of the corresponding user-optimal response, i.e., a path selection algorithm that satisfies the user's requirements at minimal cost. We show that the underlying noncooperative game among users has a unique equilibrium, for any particular choice of price functions. Then, we establish the existence of incentive compatible price functions, which drive the network into an equilibrium point that coincides with the optimum of a social function. Specifically, these price functions are the derivatives of the social function. We then extend our results to scenarios in which users can identify only sub-optimal paths, as is often the case with multi-constrained path optimization.     

Specifying and analyzing early requirements in Tropos

We present a framework that supports the formal verification of early requirements specifications. The framework is based on Formal Tropos, a specification language that adopts primitive concepts for modeling early requirements (such as actor, goal, and strategic dependency), along with a rich temporal specification language. We show how existing formal analysis techniques, and in particular model checking, can be adapted for the automatic verification of Formal Tropos specifications. These techniques have been implemented in a tool, called the T-Tool, that maps Formal Tropos specifications into a language that can be handled by the NuSMV model checker. Finally, we evaluate our methodology on a course-exam management case study. Our experiments show that formal analysis reveals gaps and inconsistencies in early requirements specifications that are by no means trivial to discover without the help of formal analysis tools.

Renal pathology in WAGR syndrome

The Wilms' tumor-aniridia-genital anomalies-mental retardation (WAGR) syndrome is associated with an increased risk for developing Wilms' tumor. A right nephrectomy was performed following the diagnosis of Wilms' tumor in a 2-year-old girl with WAGR syndrome and chromosome 11, del 11p13. Pathologic examination revealed intralobar nephrogenic rests and a peripelvic multicystic mass, sharply delineated from the adjacent typical intralobar nephrogenic rests and renal parenchyma, which may represent a cystic Wilms' tumor (cystic partially differentiated nephroblastoma). We studied the expression of the H19 gene by in-situ hybridization performed on paraffin sections of the kidney. H19 is an imprinted maternally-expressed gene that is not translated to protein and functions as a regulatory RNA molecule. It is tightly linked with the paternally-imprinted gene of insulin-like growth factor 2. While IGF2 presumably plays a role in tumorigenesis of Wilms' tumor, H19 is not expressed in the majority of Wilms' tumors. The expression of H19 in the intralobar nephrogenic rests was found to be prominent in the component of the blastema and markedly reduced with differentiation to tubular structures similar to the fetal kidney. The differential diagnosis of hyperplastic intralobar nephrogenic rests from a small Wilms' tumor arising in intralobar nephrogenic rests is difficult. Complete understanding of the chain of molecular events occurring in the evolution of Wilms' tumors may lead to the development of tumor markers to be used on paraffin sections and so help in the differential diagnosis of hyperplasia versus malignant transformation.     

Cross-validation of the ability of the Luria-Nebraska Neuropsychological Battery to differentiate chronic schizophrenics with and without ventricular enlargement.

33 of 43 chronic schizophrenic patients (aged 20–39 yrs) were correctly classified by the Luria-Nebraska Neuropsychological Battery for the presence or absence of ventricular enlargement, as assessed by computer tomography (CT) scan. Results are comparable to those of an earlier study by C. G. Golden et al (see record 1981-29339-001). Differences between the studies and the implications of objective CT scan measurement for detecting cerebral atrophy are discussed. (25 ref) (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Agenda-based regulation of study-time allocation: When agendas override item-based monitoring.

Theories of self-regulated study assume that learners monitor item difficulty when making decisions about which items to select for study. To complement such theories, the authors propose an agenda-based regulation (ABR) model in which learners’ study decisions are guided by an agenda that learners develop to prioritize items for study, given their goals and task constraints. Across 4 experiments, the authors orthogonally manipulated 1 task constraint—the reward structure of the task—with objective item difficulty, so that learners could use either item difficulty or potential reward in deciding how to allocate their study time. Learners studied items, were tested, and then selected half the items for restudy. As predicted by the ABR model, reward structure drove item selection more than did item difficulty, which demonstrates learners’ agendas can override the effects of monitoring item difficulty in the allocation of study time. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

EquiCast: Scalable multicast with selfish users

Peer-to-peer (P2P) networks suffer from the problem of “freeloaders”, i.e., users who consume resources without contributing anything in return. In this paper, we tackle this problem taking a game theoretic perspective by modeling the system as a non-cooperative game. We introduce EquiCast, a wide-area P2P multicast protocol for large groups of selfish nodes. EquiCast is the first P2P multicast protocol that is formally proven to enforce cooperation in selfish environments. Additionally, we prove that EquiCast incurs a low constant load on each user.     

Mixing qualitative and quantitative research in developmental science: Uses and methodological choices.

Multiple methods are vital to understanding development as a dynamic, transactional process. This article focuses on the ways in which quantitative and qualitative methodologies can be combined to enrich developmental science and the study of human development, focusing on the practical questions of when and how. Research situations that may be especially suited to mixing qualitative and quantitative approaches are described. The authors also discuss potential choices for using mixed quantitative- qualitative approaches in study design, sampling, construction of measures or interview protocols, collaborations, and data analysis relevant to developmental science. Finally, they discuss some common pitfalls that occur in mixing these methods and include suggestions for surmounting them. (PsycINFO Database Record (c) 2010 APA, all rights reserved)