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81.
82.
Specific heats of saturated liquid carbon dioxide (C sat) have been measured in the temperature range 220 to 303 K. Specific heats at constant volume (C v) have been measured at 12 densities ranging from 0.2 to 2.5 times the critical density in the temperature range 233 to 330 K, with pressures varying from 3.4 to 32 MPa. The measurements have been conducted in an adiabatic constant-volume calorimeter of conventional design. Uncertainty of the specific heats is estimated to not exceed 2.0%. Comparisons are made with an extended Benedict-Webb-Rubin equation of state and with the results of other workers.  相似文献   
83.
Thorup and Zwick (J. ACM 52(1):1–24, 2005 and STOC’01) in their seminal work introduced the notion of distance oracles. Given an n-vertex weighted undirected graph with m edges, they show that for any integer k≥1 it is possible to preprocess the graph in $\tilde {O}(mn^{1/k})$ time and generate a compact data structure of size O(kn 1+1/k ). For each pair of vertices, it is then possible to retrieve an estimated distance with multiplicative stretch 2k?1 in O(k) time. For k=2 this gives an oracle of O(n 1.5) size that produces in constant time estimated distances with stretch 3. Recently, Pǎtra?cu and Roditty (In: Proc. of 51st FOCS, 2010) broke the theoretical status-quo in the field of distance oracles and obtained a distance oracle for sparse unweighted graphs of O(n 5/3) size that produces in constant time estimated distances with stretch 2. In this paper we show that it is possible to break the stretch 2 barrier at the price of non-constant query time in unweighted undirected graphs. We present a data structure that produces estimated distances with 1+ε stretch. The size of the data structure is O(nm 1?ε) and the query time is $\tilde {O}(m^{1-\varepsilon '})$ . Using it for sparse unweighted graphs we can get a data structure of size O(n 1.87) that can supply in O(n 0.87) time estimated distances with multiplicative stretch 1.75.  相似文献   
84.
Alfalfa, corn, sorghum, and wheat forages were harvested for ensiling. Effects of inoculation of the forages with Lactobacillus plantarum (107/g silage) were studied in small experimental 55-kg drum silos. Control and treated silages were prepared, and drums from each treatment were opened on days 1, 2, 4, 8, 16, and 33. Proximate analysis, pH, neutral detergent fiber, acid detergent fiber, soluble carbohydrate, lactic acid, and volatile fatty acid contents were measured. Total faculative anaerobic microflora were increased in all silages by addition of L. plantarum, and numbers of lactobacilli, were increased in all but corn silage. Yeasts and molds were lower only in inoculated alfalfa and wheat silages. The effect of the inoculum was observed on chemical composition only for alfalfa and wheat silages. These treated silages had a lower pH, higher lactic acid content, and great recovery of dry matter, crude protein, and detergent fiber (alfalfa) and nitrogen-free extract (wheat). Inoculation has an effect on microflora in all silages and a positive beneficial effect on nutrient recovery in alfalfa and wheat silages.  相似文献   
85.
An efficient method is described for evaluating the error-checking syndrome for systems which are modified cyclic or shortened cyclic codes to detect slips of block synchronisation.  相似文献   
86.
There are four groups of RNA bacteriophages with distinct antigenic and physicochemical properties due to differences in surface residues of the viral coat proteins. Coat proteins also play a role as translational repressor during the viral life cycle, binding an RNA hairpin within the genome. In this study, the first crystal structure of the coat protein from a Group II phage GA is reported and compared to the Group I MS2 coat protein. The structure of the GA dimer was determined at 2.8 A resolution (R-factor = 0.20). The overall folding pattern of the coat protein is similar to the Group I MS2 coat protein in the intact virus (Golmohammadi R, Valeg?rd K, Fridborg K, Liljas L. 1993, J Mol Biol 234:620-639) or as an unassembled dimer (Ni Cz, Syed R, Kodandapani R. Wickersham J, Peabody DS, Ely KR, 1995, Structure 3:255-263). The structures differ in the FG loops and in the first turn of the alpha A helix. GA and MS2 coat proteins differ in sequence at 49 of 129 amino acid residues. Sequence differences that contribute to distinct immunological and physical properties of the proteins are found at the surface of the intact virus in the AB and FG loops. There are six differences in potential RNA contact residues within the RNA-binding site located in an antiparallel beta-sheet across the dimer interface. Three differences involve residues in the center of this concave site: Lys/Arg 83, Ser/Asn 87, and Asp/Glu 89. Residue 87 was shown by molecular genetics to define RNA-binding specificity by GA or MS2 coat protein (Lim F. Spingola M, Peabody DS, 1994, J Biol Chem 269:9006-9010). This sequence difference reflects recognition of the nucleotide at position -5 in the unpaired loop of the translational operators bound by these coat proteins. In GA, the nucleotide at this position is a purine whereas in MS2, it is a pyrimidine.  相似文献   
87.
To assess relationships between parameters of mechanical ventilation (MV) and portable chest X-ray (CXR) measurements of lung length (LL) and severity of air space disease, a prospective, randomized, blinded comparison of 102 adults in a university hospital was performed. Each patient received two portable, supine CXRs on different MV breaths within 5 min of one another. Ventilator parameters were recorded. All 204 CXRs were randomly assorted and read independently by three radiologists. Air space disease was considered more severe with pressure support ventilation (PSV) breaths than with intermittent mandatory ventilation (IMV) breaths (p = 0.0003), and its extent correlated inversely with static compliance (p = 0.0001, r = -0.40). Among patients having CXRs on both IMV and PSV breaths, 15 of 67 (22%) had their overall degree of air space disease read differently by one category (mild, moderate, or severe). Increases in LL between the two CXRs were associated with increasing peak (p = 0.0038) or mean (p = 0.0065) airway pressure, tidal volume (VT) (p = 0.022), and VT per kilogram (p = 0.006). We conclude that lung volume changes during MV, typically not noted nor controlled for during portable chest radiography, may substantially alter the interpretation of air space disease and LL. Physicians monitoring intensive care unit (ICU) patients with daily CXRs should be aware of the variables influencing interpretation of portable CXRs of ICU patients.  相似文献   
88.
Management of forthcoming exascale clusters requires frequent collection of run‐time information about the nodes and the running applications. This paper presents a new paradigm for providing online information to the management system of scalable clusters, consisting of a large number of nodes and one or more masters that manage these nodes. We describe the details of resilient gossip algorithms for sharing local information within subsets of nodes and for sending global information to a master, which holds information on all the nodes. The presented algorithms are decentralized, scalable and resilient, working well even when some nodes fail, without needing any recovery protocol. The paper gives formal expressions for approximating the average ages of the local information at each node and the information collected by the master. It then shows that these results closely match the results of simulations and measurements on a real cluster. The paper also investigates the resilience of the algorithms and the impact on the average age when nodes or masters fail. The main outcome of this paper is that partitioning of large clusters can improve the quality of information available to the management system without increasing the number of messages per node. Copyright © 2015 John Wiley & Sons, Ltd.  相似文献   
89.
The present study evaluates a novel sister hole cooling technique using large inclination angle cylindrical holes simulated numerically. Here, a 55° inclination angle has been applied to simulate more realistic turbine conditions. Two sister holes bound the primary injection hole and are shifted slightly downstream to promote flow adhesion. As a means of determining the validity of the technique, adiabatic effectiveness and vortex flow structures were evaluated at four blowing ratios: 0.2, 0.5, 1.0, and 1.5. The results indicate that the sister hole technique dramatically reduces the primary kidney vortex pair offering significant improvements in effectiveness at all blowing ratios.  相似文献   
90.
The construction of the Delaunay triangulation depends on the correct determination of whether or not a fourth point is inside the circle determined by three other points. By modeling the data points as disks and examining the associated mutual tangent circles, we show how to construct an incircle test that is reliable and sharp, one that is not corrupted by round-off error, one that can deal with inexact input data, avoids rational and big integer arithmetic, and brings geometry to the forefront instead of error analysis or arithmetic.  相似文献   
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