A Partitioning-Independent Paradigm for Nested Data Parallelism

A generalization of the data parallel model has been proposed by Blelloch which permits the nesting of data parallel operators to specify parallel computation across nested and irregular data structures. In this paper we consider the costs of supporting the general model of nested data parallelism, analyzing the requirements such a model places upon an underlying model of execution. We propose a new multi-node execution model which meets the needs of the paradigm and is additionally generic in the partitioning of data aggregates within the system. The basis for our execution model is an abstract machine based upon elementary notions of nodal multi-threading. We demonstrate the utility of our proposal by providing a full definition for a simple nestable one-dimensional data parallel operator. We discuss the applicability of our design to existing multi-processor machines, illustrating performance statistics gathered from a prototype system we have constructed on the Thinking Machines CM-5.     

Periodic review and joint replenishment in stochastic demand environments

In this paper we consider periodic review systems under stochastic demands. First, we study the single product periodic review problem and propose a simple solution procedure which is near optimal. Then, given the existence of this simple procedure, we study the joint replenishment problem for multiple items under stochastic demands and suggest simple heuristics which provide very good results. We find the simple procedures combined with the robustness of the cost function to be very attractive in other applications which require coordination of cycle times under stochastic demands.     

Expandable metal stents for the treatment of colonic obstruction: techniques and outcomes

Modulation of CD8(+) T-cell responses specific for an exogenous antigen by epitope variants would be advantageous to develop a novel means of antigen-specific immune regulation. We have analyzed CD8(+) T-cell responses to single amino acid-substituted variants of a peptide corresponding to residues 142-149 (p142-149; LAYFYPEL) of alphas1-casein, a major milk allergen, which is a dominant determinant restricted by H-2Kb. An analog peptide L142I with a substitution of Ile for Leu at the nonanchor N-terminal residue induced more IFN-gamma secretion than p142-149 from specific CD8(+) T cells. Furthermore, L142I could prime CD8(+) T cells more efficiently in vivo, and these L142I-primed cells secreted more IFN-gamma than p142-149-primed CD8(+) T cells upon stimulation with p142-149 in vitro. These findings are mainly explained by the greater ability of L142I to form stable Kb-peptide complexes. These findings indicate that appropriate analog peptides may be useful as efficient inducers of CD8(+) T cells which recognize the parent peptide and secrete IFN-gamma, a potent inhibitor of Th2-dependent events, including IgE production.     

Emission characteristics of some dilute tungsten alloys

The effective work functions of nine tungsten-base alloys were measured. The second constituents were: 1) 5 pct Re, 2) 15 pct Re, 3) 2.5 pct Os, 4) 5 pct Os, 5) 1 pct Ir, 6) 2 pct Ir, 7) 5 pct Ta, 8) 10 pct Ta, and 9) 26 pct Ta. Work functions were determined from vacuum emission vehicle and thermionic emission microscope measurements. Mosaics of each surface were produced from the microscope which show the grain structure of the alloys and some anomalous emission areas. Some exceptionally high bare work functions were observed from samples with small alloy additions. For example, the work function of W1 pct Ir was 5.3 eV. DEAN LEO JACOBSON, formerly Section Manager, Electro-Optical Systems, Division of Xerox Corp., Pasadena, Calif.     

Binary division using a data-dependent iterative array

An iterative array is proposed which can be used to carry out binary division based on the principle of successive subtraction. The function of each cell of the array is dependent on the result of subtraction in the array.     

Cluster analyses of interest inventory scales as tests of Holland's occupational classification.

Compared J. L. Holland's occupational categories with groups of occupations that resulted from the application of L. L. McQuitty and J. A. Clark's iterative intercolumnar correlational analysis to the scales of the Strong Vocational Interest Blank, the Minnesota Vocational Interest Inventory, and the Kuder Occupational Interest Survey for men and women. Results indicate that clusters of occupations exist that are internally consistent, and these usually agreed with the groups of occupations in Holland's classification. The hierarchical structure of the clusters followed the hexagonal ordering of Holland's occupational categories suggested in other studies. In addition, the usefulness of all 3 letters in Holland's occupational classification was supported. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Matching and mismatching: The effect of own limit, other's toughness, and time pressure on concession rate in negotiation.

Augmented the research design used by H. H. Kelley et al (1967) to examine negotiation about the division of a common reward to include 2 factors expected to interact with bargainer's limit: time pressure and the other bargainer's toughness. Five hypotheses were tested: (1) Concession rate is lower the higher a bargainer's limit; (2) concession rate is greater under high, as opposed to low, time pressure; (3) bargainer toughness is mismatched, that is, the greater the other's initial demand and the slower the other's concessions, the larger will be the S's concessions; (4) concession rate is more influenced by limit level under high, as opposed to low, time pressure; and (5) mismatching of the other's toughness is more pronounced under high time pressure than under low. Ss were 48 female undergraduates. All hypotheses were supported except Hypothesis 3, which received partial support. Ss conceded slowly when the other conceded slowly and rapidly when the other conceded rapidly. A possible explanation for this finding is that matching occurs when it is possible to judge the fairness of the other's offers. When this is possible, bargainers engage in reciprocity. (13 ref) (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Silicon Force Transducer for Extraluminal Measurement of Oviduct Contractile Activity

A miniature, implantable force transducer has been developed for the extraluminal measurement of segmental smooth muscle contractility and has been applied to the oviduct in the Macaca mulatta. The force transducer makes use of a commercially available piezoresistive silicon strain sensor bonded to a flexible metal strip. The device is housed in a tissue compatible, gas sterilizable tubule upon which are placed sutures for subsequent extraluminal attachment to an organ.     

Deep traps in GaAs revealed at high resolution by simple fast photocapacitance methods

The characteristics of a new type of capacitance spectroscopy of deep traps in semiconductors are reviewed. A double radiation source technique is employed, the first source controlling the occupation of the traps and the characteristic time constant of the experiment, the second probing the spectral distribution of traps by selectively photoinducing emission to the conduction and valence bands. Time differentiation enhances the detectivity of the traps and minimizes drift problems. Typical spectra obtained with this quasi-equilibrium spectroscopic technique are described. The chromium trap in GaAs presents a distinctive feature with interesting properties which are discussed. Comparisons with thermal capacitance measurements are made, showing the complementary nature of the two methods. The use of the technique to detect out-diffusion of Cr from an insulating substrate into an epitaxial layer is described.     

A 2000 gate 10 n sec uncommitted logic array for telecommunications and computer applications

This paper discusses the development programme used for a VLSI bipolar process for the production of a 2000 Gate ULA.