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81.
Bill Hancock 《Network Security》1995,1995(5):10-12
The author has become very concerned that many sites are not properly adhering to US export regulations in the area of technical data and restricted technical science as prescribed by US law. The author strongly recommends that legal counsel be contacted with the above information and components and documents be put into place at customers to ensure that violation of any export law is not possible and that proper maintenance of restricted entities is maintained. 相似文献
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Dolev S. Israeli A. Moran S. 《IEEE transactions on pattern analysis and machine intelligence》1995,21(5):429-439
We introduce a novel technique, the scheduler luck game (in short sl-game) for analyzing the performance of randomized distributed protocols. We apply it in studying uniform self-stabilizing protocols for leader election under read/write atomicity. We present two protocols for the case where each processor in the system can communicate with all other processors and analyze their performance using the sl-game technique 相似文献
84.
Fine-spray (water mist) protection of shipboard engine rooms 总被引:1,自引:0,他引:1
Twenty-three fire tests were conducted to determine the ability of current fine-spray (water mist) technologies to extinguish fires specified in the International Maritime Organization (IMO) fire test procedure for engine rooms greater than 3000 m3. The tests were conducted using nozzle installed at a 5 m height and 1·5 m spacing in a large test facility (2800 m2 area and 18 m height). Two types of nozzles were tested: a low pressure nozzle operating between 1·2 and 1·5 MPa with flow per nozzle between 12·0 and 13·41/m and a multi-nozzle high-pressure prototype consisting of seven nozzles operating at 6·9 MPa flowing at 5·3 1/m per prototype. These nozzles were selected because they had been shown to extinguish IMO fire tests in enclosures with a protected area of 83 m2 and a ceiling height of 4·5 m. The fire tests selected from the IMO procedure included 6 MW diesel spray fires on top of the IMO engine mock-up, a shielded 6 MW diesel spray fire adjacent to the mock-up, a 1 MW shielded diesel spray fire adjacent to the mock-up, and a wood crib within a 2 m2 pan filled with heptane. In tests in which no additional enclosure surrounded the nozzles other than the test facility, fires were not significantly affected by the water mist using either nozzle. To further investigate mist-system capabilities, a ceiling was then placed directly over the nozzles at a 5 m height covering an area of 188 m2. Using 90 high-pressure prototype nozzles, the test fires were not extinguished. A 940 m3 enclosure was then formed by dropping tarpaulins to the floor from the ceiling. A 4 m2 vent was placed in the wall. With the 90 high-pressure prototype nozzles, the 6 MW spray fire on top of the mock-up was extinguished. When the 6 MW fire was shielded beside the mock-up, the fire was not extinguished. With the vent closed, the 6 MW shielded spray fire was extinguished. Under the same test conditions, a 1 MW shielded diesel spray fire and a 0·1 m2 heptane pool fire were not extinguished. The fire test results indicated that protection of engine rooms with volumes of about 1000 m3 is possible by optimizing current fine-spray technology while significantly larger volumes will require improved discharge characteristics. 相似文献
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D Buggy P Higgins C Moran D O''Brien F O''Donovan M McCarroll 《Canadian Metallurgical Quarterly》1997,84(1):106-110
The expression of tissue transglutaminase (tTG) was studied during the formation of the normal human placenta and in molar pregnancies and choriocarcinoma, in order to correlate its expression with the functional characteristics of the recognized trophoblast cell types. tTG expression was found to be developmentally regulated. Before 6-7 weeks' gestation, only the chorionic villous cytotrophoblast expresses tTG. Thereafter the overlying syncytiotrophoblast becomes positive. tTG expression is gradually downregulated in the intermediate trophoblast cells emerging from the tips of the chorionic villi invading the uterine tissue. In the decidual wall, the intermediate trophoblast does not express tTG, whereas scattered syncytial cells, the placental bed giant cells, express tTG. Villi from complete hydatidiform mole (CHM) show tTG expression in both the cyto- and the syncytiotrophoblast. The intermediate trophoblast cells from CHM show heterogeneous tTG expression, with a majority of negative cells, whereas extravillous syncytia always express tTG. In choriocarcinoma, the tumour cells show heterogeneous tTG expression, with a majority of positive cells. Analysis of tTG protein and mRNA in placental extracts by Western and Northern blotting did not provide evidence for expression of the truncated form of tTG found in some cell types. The regulated expression of tTG in the normal placenta suggests that the enzyme is involved in important trophoblastic functions and may participate in the control of invasion. 相似文献
90.
A mathematical model was developed to estimate the efficacy of coagulation–flocculation treatment for removing neutral hydrophobic organic chemicals from raw drinking water. The model assumed that the only significant removal mechanism was the destabilization and settling of organic matter containing sorbed anthropogenic organic compounds. The model was validated with standard jar tests using compounds with a range of hydrophobicities (log?Kow = 1.89?to?5.48), including contaminant candidate list chemicals, pesticides, pharmaceuticals, and endocrine disrupting chemicals. Final concentrations of test compounds after coagulation and flocculation were in good agreement with model estimations for synthetic waters composed of Aldrich (Milwaukee, WI) humic acid solutions. The final compound concentrations in coagulated natural waters from two drinking water reservoirs were about 80% lower than those estimated with the model. Overestimations of treated water concentrations by the model were attributed to an increase in sorption by natural organic matter when coiled in aluminum hydroxide flocs, compared to sorption to dispersed natural organic matter in untreated water. 相似文献