Reusing semi-specified behavior models in systems analysis and design

As the structural and behavioral complexity of systems has increased, so has interest in reusing modules in early development phases. Developing reusable modules and then weaving them into specific systems has been addressed by many approaches, including plug-and-play software component technologies, aspect-oriented techniques, design patterns, superimposition, and product line techniques. Most of these ideas are expressed in an object-oriented framework, so they reuse behaviors after dividing them into methods that are owned by classes. In this paper, we present a crosscutting reuse approach that applies object-process methodology (OPM). OPM, which unifies system structure and behavior in a single view, supports the notion of a process class that does not belong to and is not encapsulated in an object class, but rather stands alone, capable of getting input objects and producing output objects. The approach features the ability to specify modules generically and concretize them in the target application. This is done in a three-step process: designing generic and target modules, weaving them into the system under development, and refining the combined specification in a way that enables the individual modules to be modified after their reuse. Rules for specifying and combining modules are defined and exemplified, showing the flexibility and benefits of this approach.

Sparse pixel vectorization: an algorithm and its performanceevaluation

Accurate and efficient vectorization of line drawings is essential for their higher level processing. We present a thinningless sparse pixel vectorization (SPV) algorithm. Rather than visiting all the points along the wire's black area, SPV sparsely visits selected medial axis points. The result is a crude polyline, which is refined through polygonal approximation by removing redundant points. Due to the sparseness of pixel examination and the use of a specialized data structure, SPV is both time efficient and accurate, as evaluated by our proposed performance evaluation criteria     

Nd:YAG laser treatment for premacular hemorrhage

The authors describe two cases of premacular hemorrhage secondary to retinal macroaneurysm, with significant loss of vision. A few low-energy bursts of ND:YAG laser were applied to perforate the anterior surface of the hemorrhage, subsequently draining the blood into the vitreous cavity. The blood gradually cleared from the vitreous, with restoration of good vision. Nd:YAG laser seems to be a safe and efficient method for treating premacular hemorrhage and should be considered as a therapeutic option.     

Effects of divided attention on encoding and retrieval processes in human memory: further support for an asymmetry

Despite a tradition in cognitive psychology that views encoding and retrieval processes in human memory as being similar, F. I. M. Craik, R. Govoni, M. Naveh-Benjamin and N. D. Anderson (1996) have recently shown that notable differences exist between the 2 when divided-attention manipulations are used. In this article, the authors further examined this asymmetry by using several manipulations that changed task demands at encoding and retrieval. The authors also used a secondary-task methodology that allowed a microlevel analysis of the secondary-task costs associated with encoding and retrieval. The results illustrated the resiliency of retrieval processes to manipulations involving different task demands. They also indicated different loci of attention demands at encoding and retrieval. The authors contend that whereas encoding processes are controlled, retrieval processes are obligatory but do require attentional resources for their execution.     

Adaptive K-NN for the detection of air pollutants with a sensor array

The field of air-quality monitoring is gaining increasing interest, with regard to both indoor environment and air-pollution control in open space. This work introduces a pattern recognition technique based on adaptive K-nn applied to a multisensor system, optimized for the recognition of some relevant tracers for air pollution in outdoor environment, namely benzene, toluene, and xylene (BTX), NO/sub 2/, and CO. The pattern-recognition technique employed aims at recognizing the target gases within an air sample of unknown composition and at estimating their concentrations. It is based on PCA and K-nn classification with an adaptive vote technique based on the gas concentrations of the training samples associated to the K-neighbors. The system is tested in a controlled environment composed of synthetic air with a fixed humidity rate (30%) at concentrations in the ppm range for BTX and NO/sub 2/, in the range of 10 ppm for CO. The pattern recognition technique is experimented on a knowledge base composed of a limited number of samples (130), with the adoption of a leave-one-out procedure in order to estimate the classification probability. In these conditions, the system demonstrates the capability to recognize the presence of the target gases in controlled conditions with a high hit-rate. Moreover, the concentrations of the individual components of the test samples are successfully estimated for BTX and NO/sub 2/ in more than 80% of the considered cases, while a lower hit-rate (69%) is reached for CO.     

Vector-based arc segmentation in the machine drawing understandingsystem environment

Arcs are important primitives in engineering drawings. Extracting these primitives during the lexical analysis phase is a prerequisite to syntactic and semantic understanding of engineering drawings within the machine drawing understanding system. Bars are detected by the orthogonal zig-zag vectorization algorithm. Some of the detected bars are linear approximations of arcs. As such, they provide the basis for arc segmentation. An arc is detected by finding a chain of bars and a triplet of points along the chain. The arc center is first approximated as the center of mass of the triangle formed by the intersection of the perpendicular bisectors of the chords these points define. The location of the center is refined by recursively finding more such triplets and converging to within no more than a few pixels from the actual arc center after two or three iterations. The high performance of the algorithm, demonstrated on a set of real engineering drawings, is due to the fact that it avoids both raster-to-vector and massive pixel-level operations, as well as any space transformations     

Avalanche electron injection in 4-nmSi3N4/8-nm SiO2 dielectric structure:turn-around phenomenon and Si-SiO2 interface degradation

Charge trapping and interface-state generation in very thin nitride/oxide (4-nm Si₃N₄+8-nm SiO₂) composite gate insulators are studied as a function of gate electrode work function and bottom oxide thickness. The behavior of the trapped positive charge under bias-temperature stress after avalanche electron injection (AEI) is investigated. Evidence is presented that secondary hole injection from the anode (gate/Si₃N₄ interface) and subsequent trapping near the SiO₂-Si interface result in a turnaround of the flatband voltage shift during AEI from the substrate. Just like the thermal oxides on Si, slow-state generation near the SiO₂-Si interface and boron acceptor passivation in the surface-space charge layer of the Si substrate are also observed after AEI in these nitride/oxide capacitors, and they are found to be strongly related to the secondary hole injection and trapping. Finally, interface-state generation can take place with little secondary anode hole injection and is enhanced by the occurrence of hole trapping     

Negotiating Norms of Discussion in the Public Arena: The Use of Irony in Israeli Political Radio Phone‐In Programs

Phone‐in radio programs are part of the public sphere and thus require open access, rationality, and practicality. Simultaneously, they are a media product, which requires entertaining content. We demonstrate these demands through the analysis of interactional irony in Israeli political radio phone‐ins. From an emic perspective, callers see irony as detrimental to the discussions, yet hosts and regular callers use it to make entertaining interactions. Irony is a critical tool that points to violations of norms: the norm of a clear 2‐sided interaction; norms akin to the Habermasian public sphere; and at the content level, irony is used to reject racist positions. Being indirect, irony can be used to create an entertaining yet critical discussion in the public sphere.