Doubly-striped disk mirroring: Reliable storage for video servers

Disk striping is essential in Video-On-Demand servers to allow concurrent access for a large number of users to the same copy of a video object. On the other hand, disk striping makes the system more vulnerable to component failures. We propose a replication scheme for video content and an associated I/O scheduling algorithm that enables the system to tolerate a component failure. The scheme, called doubly-striped mirrors, compares favorably to other approaches for implementing redundancy such as RAID in terms of cost, bandwidth efficiency, buffer usage and system availability.     

Sampling improvements in atomic absorption spectroscopy

Atomic absorption spectroscopy is being used as a routein method to determine sodium, potassium, calcium, magnesium, copper and many other metallic elements in oils, fats, milk and other substances. Copper and iron can be measured directly in milk without sample preparation. When highly acidified samples are run, a new plastic-lined nebulizer is useful to prevent spurious results due to corrosion. A new sampling device, the Graphite Furnace, can analyze extremely small samples and gives detection limits in the picogram (10⁻¹² g) range. One of 28 papers presented at the Symposium, “Metal-Catalyzed Lipid Oxidation,” ISF-AOCS World Congress, Chicago, September 1970.     

Detection and display of defects in medical scintigraphic images

To achieve the evaluation of the lesion detectability of a program implemented by us on a minicomputer system to indicate possible defects on liver scans, we simulated a set of geometrical phantoms with different patterns of cold lesions to obtain LROC curves in different cases. Then, to check its clinical value, the program was applied to 44 liver scintigrams of patients among which 7 occurred to be pathological. These liver scintigrams had been evaluated by 6 clinicians so that a comparison between the program and the clinicians could be performedd on the basis of the corresponding LROC curves. Moreover, once an abnormality had been detected by the program, the abnormality was processed in order to perform a psychovisual evaluation of the image more easily: an adapted local 2-level display of the possible defect was superimposed on the scan to enhance it and to facilitate diagnosis.     

High flux hemofiltration

Experiments were performed using a new hollow fiber hemofilter. Ultrafiltration rates and whole blood urea clearances were measured in post-dilution hemofiltration. High ultrafiltration rates were obtained with the new hemofilter. No adverse effects were detected despite filtration fractions above 45%. These experiments suggest that it is possible in post-dilution hemofiltration to obtain small solute clearances comparable to those of hemodialysis without apparent deleterious effects.     

Etude structurale des phases Sc5,5Nb1,5O12 et Sc5,5Ta1,5O12. Ordre des cations dans les composes (A,B)7O12 de type Y6UO12

New phases Sc_5,5Nb_1,5O₁₂ and Sc_5,5Ta_1,5O₁₂ were prepared. Their structure is rhombohedral (space group R3, Z = 1) ($\text{a}\text{= 6,080}\text{A}\text{?}\text{α = 99°16}$ (niobate), $\text{a}\text{= 6,084}\text{A}\text{?}\text{α = 99°18}$ (tantalate). Many (A,B)₇O₁₂ ternary oxides have the same fluorite-related structure, the distortion from the cubic lattice depending upon ordering of cations on non-equivalent atomic positions. A sensitive influence of the degree of ordering is observed in the vibrational spectra of those phases.     

Timed substitutions for regular signal-event languages

In the classical framework of formal languages, a refinement operation is modeled by a substitution and an abstraction by an inverse substitution. These mechanisms have been widely studied, because they describe a change in the specification level, from an abstract view to a more concrete one, or conversely. For timed systems, there is up to now no uniform notion of substitution. In this paper, we study timed substitutions in the general framework of signal-event languages, where both signals and events are taken into account. We prove that regular signal-event languages are closed under substitution and inverse substitution. To obtain these results, we use in a crucial way a “well known” result: regular signal-event languages are closed under intersection. In fact, while this result is indeed easy for languages defined by Alur and Dill’s timed automata, it turns out that the construction is much more tricky when considering the most involved model of signal-event automata. We give here a construction working on finite and infinite signal-event words and taking into account signal stuttering, unobservability of zero-duration τ-signals and Zeno runs. Note that if several constructions have been proposed in particular cases, it is the first time that a general construction is provided.     

Approximate bisimulation relations for constrained linear systems

In this paper, we define the notion of approximate bisimulation relation between two continuous systems. While exact bisimulation requires that the observations of two systems are and remain identical, approximate bisimulation allows the observations to be different provided the distance between them remains bounded by some parameter called precision. Approximate bisimulation relations are conveniently defined as level sets of a so-called bisimulation function which can be characterized using Lyapunov-like differential inequalities. For a class of constrained linear systems, we develop computationally effective characterizations of bisimulation functions that can be interpreted in terms of linear matrix inequalities and optimal values of static games. We derive a method to evaluate the precision of the approximate bisimulation relation between a constrained linear system and its projection. This method has been implemented in a Matlab toolbox: MATISSE. An example of use of the toolbox in the context of safety verification is shown.     

Response inhibition deficit is involved in poor decision making under risk in nonamnesic individuals with alcoholism.

Individuals with alcoholism exhibit poor decision making as reflected by their continued alcohol use despite encountering problems and by low performance in laboratory tasks of decision making. Here, the authors investigated the relative contribution of several distinct processes of executive functions in performance on the Iowa Gambling Task (IGT; A. Bechara, A. R. Damasio, H. Damasio, & S. W. Anderson, 1994) in recently detoxified individuals with alcoholism. Compared to matched healthy participants, individuals with alcoholism showed below-normal scores in the last 20 trials of the IGT as well as on other tasks of executive functions, specifically those assessing the capacity to manipulate information stored in working memory, detect abstract rules, or inhibit prepotent responses. Prepotent response inhibition best predicted performance in the late trials of the IGT, that is, when participants have likely acquired knowledge about the reward/punishment contingencies of the task. These results underline the important role that response inhibition plays in decision making, especially in risky situations, when knowledge of the probability of a given outcome becomes available (i.e. decisions under risk). (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

10 × 10 Gb/s DWDM Transmission Through 2.2-km Multimode Fiber Using Adaptive Optics

Transmitter-based adaptive optics and receiver-based single-mode filtering are combined to compensate modal dispersion in multimode fiber (MMF). A liquid-crystal spatial light modulator controls the launched field pattern for ten 10-Gb/s nonreturn-to-zero channels, wavelength-division multiplexed on a 200-GHz grid in the C-band. Error-free transmission through 2.2 km of 50-mum graded-index MMF is achieved for launch offsets up to 10 mum and for worst-case launched polarization. A ten-channel transceiver based on parallel integration of electronics and photonics is employed.     

Embedded holonic fault diagnosis of complex transportation systems

The use of electronic equipment and embedded computing technologies in modern complex transportation systems continues to grow in a highly competitive market, in which product maintainability and availability is vital. These technological advances also make fault diagnosis and maintenance interventions much more challenging, since these operations require a deep understanding of the entire system. This paper proposes a holonic cooperative fault diagnosis approach, along with a generic architecture, to increase the embedded diagnosis capabilities of complex transportation systems. This concept is applied to the fault diagnosis of door systems of a railway transportation system.