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71.
Sang Boem Lim Hanku Lee Bryan Carpenter Geoffrey Fox 《The Journal of supercomputing》2008,43(2):165-182
The paper research is concerned with enabling parallel, high-performance computation—in particular development of scientific
software in the network-aware programming language, Java. Traditionally, this kind of computing was done in Fortran. Arguably,
Fortran is becoming a marginalized language, with limited economic incentive for vendors to produce modern development environments,
optimizing compilers for new hardware, or other kinds of associated software expected of by today’s programmers. Hence, Java
looks like a very promising alternative for the future.
The paper will discuss in detail a particular environment called HPJava. HPJava is the environment for parallel programming—especially data-parallel scientific programming—in Java. Our HPJava is
based around a small set of language extensions designed to support parallel computation with distributed arrays, plus a set
of communication libraries. A high-level communication API, Adlib, is developed as an application level communication library suitable for our HPJava. This communication library supports
collective operations on distributed arrays. We include Java Object as one of the Adlib communication data types. So we fully support communication of intrinsic Java types, including primitive
types, and Java object types. 相似文献
72.
This study was done to identify the cause of intestinal obstruction with particular emphasis on the gynecologic and perioperative related causes. All medical records from females with the discharge diagnosis "intestinal obstruction" from 1988 to 1991 at Columbia Presbyterian Medical Center were requested. The patient series consisted of the first 100 completed charts received. Forty-eight percent of those patients with intestinal obstruction had experienced a previous gynecologic or obstetric event that could account for the obstruction. Primarily, the gynecologist managed more than 20 percent of all female patients with intestinal obstruction. The most common causative factors contributing to intestinal obstruction were postoperative adhesions (59 percent) and tumor (17 percent). Fifty-six percent of the patients with intestinal obstruction associated with postoperative adhesions had a history of previous gynecologic and obstetric operation. Hysterectomy was the most common previously performed operation. In this series, cesarean section was less likely and myomectomy was more likely to cause subsequent intestinal obstruction than expected. Of 59 female patients with postoperative adhesions associated with intestinal obstruction, 31 had the original operative reports available for analysis. Eleven of these patients were taken to the operating room for management of the obstruction. In the nine patients who had surgical peritoneal closure in the original operation, the adhesions causing the obstruction were always to the site of reperitonealization. In the two patients in whom the peritoneum was left open, the adhesions causing obstruction were remote from the site of spontaneous reperitonealization. In an unselected patient series of intestinal obstruction, a history of previous gynecologic pathology is a significant factor contributing to the total number of instances of intestinal obstruction in females. Also, surgical peritoneal closure may result in an increase in the incidence of intestinal obstruction. 相似文献
73.
First stage slurry reactor Fischer-Tropsch (FT) yield data from Mobil's two-step pilot plant operations for the DOE have been correlated using a modified Schulz-Flory approach but allowing for changes in the probability of chain growth, , at key product molecular weights. Triple values of are invoked to explain (1) the high methane yield and (2) the very broad molecular weight distribution of the wax fraction, as compared to (3) moderate values of 2 of between 0.79 and 0.85 for the C2–C20 hydrocarbons. Over this range, wax yields from 10 to 76 wt% are accommodated, at values of 3 from 0.90 to 0.98. The second break in the yield-molecular weight curve occurs at the carbon number where most of the component remains in the reactor as liquid rather than leaving as vapor product. It is assumed that this is a function of vapor-liquid equilibrium. The correlation has proven useful in developing a computer model of the FT synthesis loop which is part of a baseline design and economic study for DOE/PETC. 相似文献
74.
75.
Essential role of beta-adrenergic receptor kinase 1 in cardiac development and function 总被引:1,自引:0,他引:1
76.
KK M?kinen CY Chen PL M?kinen CA Bennett PJ Isokangas KP Isotupa HR Pape 《Canadian Metallurgical Quarterly》1996,30(3):180-188
The concern with nursing research in the future work of nurse graduates. Expectations from the viewpoint of the nurse researcher. Keeping in mind the concerns which occupy nurse researchers now and in the future, expectations are raised of the graduates of degree programmes in nursing science which are now also being established in the Federal Republic of Germany. This takes into account the structurally determined areas of self determined action in new fields of professional practice. Nurse graduates will be seen as "change agents" in their future areas of work and will have three essential aspects of involvement with nursing research: 1. they themselves will conduct research 2. they will receive, put into practice and transmit results of nursing research 3. they will initiate and commission nursing research projects. According to the broad topics of nursing research, requirements for nurses to act as professionals in their new working fields are formulated referring to the given structural conditions in Germany. 相似文献
77.
Floor control refers to the need for coordinating activities occurred in synchronously cooperating applications shared among
collaborators. We address this for ubiquitous collaboration—the capability of multiple users to link together with disparate
access device anytime and anywhere. Floor control has been studied for years but most researchers focus on relaxed coordination
mechanisms with stationary devices that allow updates by any user on any object and resolve the uncoordinated updates. In
this paper we present a floor control mechanism, called XGSP-Floor, which implements a coordination mechanism at application
level for enabling users to consistently share the same resource in real time (synchronous collaboration) in ubiquitous collaboration
environment. The implementation platform on cell phone devices may not be new. But we believe the implementation and experiment
for XGSP-Floor on cell phone devices is a new challenge in ubiquitous collaboration environment even though the coordination
mechanism can intuitively impose a tremendous overhead in worst case. We also describe the results of the modeling of XGSP-Floor
and formal verification to prove the correctness of the modeling using Colored Petri Nets. We describe lessons learned and
discuss future work. 相似文献
78.
Charles W. Fox Ben Mitchinson Martin J. Pearson Anthony G. Pipe Tony J. Prescott 《Autonomous Robots》2009,26(4):223-239
Actuated artificial whiskers modeled on rat macrovibrissae can provide effective tactile sensor systems for autonomous robots.
This article focuses on texture classification using artificial whiskers and addresses a limitation of previous studies, namely,
their use of whisker deflection signals obtained under relatively constrained experimental conditions. Here we consider the
classification of signals obtained from a whiskered robot required to explore different surface textures from a range of orientations
and distances. This procedure resulted in a variety of deflection signals for any given texture. Using a standard Gaussian
classifier we show, using both hand-picked features and ones derived from studies of rat vibrissal processing, that a robust
rough-smooth discrimination is achievable without any knowledge of how the whisker interacts with the investigated object.
On the other hand, finer discriminations appear to require knowledge of the target’s relative position and/or of the manner
in which the whisker contact its surface.
Electronic Supplementary Material The online version of this article () contains supplementary material, which is available to authorized users.
相似文献
Anthony G. Pipe |
79.
Dirk Fox 《Datenschutz und Datensicherheit - DuD》2008,32(5):348-350
Zusammenfassung Eine Kryptoanalyse des verbreiteten Mifare-Chips, der in ca. 85% aller kontaktlosen Chipkarten zum Einsatz kommt, wurde erstmalig
auf dem CCC-Jahreskongress am 28.12.2007 vorgestellt. Inzwischen wurden weitere Details bekannt — und der Angriff erheblich
verbessert. Mitte April 2008 stellten Forscher der Radboud Universiteit Nijmegen einen Kurzfilm in You-Tube ein, in dem sie
den erfolgreichen Angriff auf eine Campus-Zugangskarte zeigen.
Dirk Fox Gesch?ftsführer der Secorvo Security Consulting GmbH und Herausgeber der DuD. 相似文献
80.