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161.
The thermoreversible gelation of poly[hexyl isocyanate] (PHIC), a rather stiff polymer, has been studied in two closely-related solvents of the alcane series, namely heptane and octane. Temperature-concentrations phase diagrams have been established for both systems. The occurrence of polymer-solvent compound is suggested in heptane but not in octane. This conclusion receives further support from neutron diffraction investigations through the use of the isotopic labelling technique. Finally, it is observed that the morphology is also affected by the solvent type although still displaying a fibrillar network structure. 相似文献
162.
Cost-benefit analysis of a single-unit system with three possible modes of the unit—normal (N), partial failure (P) and complete failure (F)—is carried out. The paper consists of two models: in model 1, the unit goes under repair (if a repairman is available) the moment it fails partially, whereas in model 2 the unit goes under repair at complete failure. The repairman appears in, and disappears from, the system randomly. A comparison between these two models after calculating MTSF and profit has also been made. 相似文献
163.
164.
SL Hoffman DL Doolan M Sedegah JC Aguiar R Wang A Malik RA Gramzinski WR Weiss P Hobart JA Norman M Margalith RC Hedstrom 《Canadian Metallurgical Quarterly》1997,15(8):842-845
Data generated in the Plasmodium yoelii rodent model indicated that plasmid DNA vaccines encoding the P.yoelii circumsporozoite protein (PyCSP) or 17 kDa hepatocyte erythrocyte protein (PyHEP17) were potent inducers of protective CD8+ T cell responses directed against infected hepatocytes. Immunization with a mixture of these plasmids circumvented the genetic restriction of protective immunity and induced additive protection. A third DNA vaccine encoding the P. yoelii sporozoite surface protein 2 (PySSP2) also induced protection. The P. falciparum genes encoding the homologues of these three protective P. yoelii antigens as well as another P. falciparum gene encoding a protein that is expressed in infected hepatocytes have been chosen for the development of a human vaccine. The optimal plasmid constructs for human use will be selected on the basis of immunogenicity data generated in mice and nonhuman primates. We anticipate that optimization of multi-gene P. falciparum DNA vaccines designed to protect against malaria by inducing CD8+ T cells that target infected hepatocytes will require extensive clinical trials during the coming years. 相似文献
165.
The high affinity growth hormone-binding protein (GHBP) circulates in human blood and represents the extracellular domain of the growth hormone (GH) receptor. It is well known that repetitive bouts of endurance type exercise result in increased integrated GH secretion. As the effects of chronic exercise on plasma GHBP levels have never been studied systematically, we investigated the effect of 2 weeks of intense endurance training on plasma GHBP as well as on plasma insulin-like growth factor (IGF)-I levels in 10 healthy, young, non-obese men. IGF-I was measured as an indicator of the effects of GH release. We also studied 10 control subjects matched for sex, age and activity, who were instructed not to change their customary activities. GHBP was determined by FPLC size exclusion chromatography and subsequent Scatchard plot analysis of the binding data; IGF-I levels were measured by RIA. The results showed that plasma IGF-I and GHBP levels were increased in the subjects who followed the training program. IGF-I and GHBP changed from 252 +/- 56 ng/ml and 912 +/- 59 pmol/l before training, to 344 +/- 61 ng/ml (p < 0.01) and 1020 +/- 48 pmol/l (p < 0.01), respectively. Another effect of the training was that the aerobic capacity of these subjects was better utilized and endurance was improved. In contrast, plasma IGF-I, GHBP, utilization of aerobic capacity and endurance did not change significantly in the control subjects. We conclude that two weeks of strenuous endurance training lead to increased plasma IGF-I and high affinity GHBP levels. 相似文献
166.
This paper presents a bibliographical survey of research, development and application of expert systems in electric power systems based on over 80 articles published since 1982. 相似文献
167.
The development of a network management strategy and a network control system for the large integrated telecommunications network (ITN) at American Express Travel Related Services Company is discussed. Network control relates to operational activities such as the diagnostics, configuration, monitoring, and performance of networks, and network management relates to all of the functions performed to manage network resources. An architecture that addresses both control and management requirements is described. Network control functions are consolidated so that operations have a single interface to the system and can operate dissimilar systems from a single workstation. NETVIEW, a licensed IBM software, performs the functions of a focal point, and the network element management system (NEMS) addresses the management of network elements. The centralization of alarms and/or alerts and issuance of commands provides immediate capability to monitor and resolve network problems through a single set of terminals as well as a platform for further automation through the use of artificial intelligence technology 相似文献
168.
169.
C V Tomy R Nagarajan S K Malik Ram Prasad N C Soni Kalyan Adhikary 《Bulletin of Materials Science》1991,14(3):691-695
151Eu Mössbauer studies have been performed on the compounds EuBa2(Cu1?x Zn x )3O7?y withx=0·0, 0·025, 0·05, 0·075 and 0·1. The parent compound, EuBa2Cu3O7?y is superconducting with a transition temperature (T c ) of 88 K.T c is depressed as Zn is substituted for Cu in this system and the compounds withx>0·05 do not show superconductivity down to 12 K.151Eu Mössbauer studies at 295 K show a single Mössbauer line in all the compounds (whether superconducting or not) with isomer shift value typical of Eu3 + ion. Further, the isomer shift values are nearly independent ofx and the temperatures down to 10 K. These observations imply that the Cu-O network responsible for superconductivity is very weakly coupled to the Eu sublattice. 相似文献
170.
Saransh Malik Sangmi Moon Bora Kim Cheolwoo You Huaping Liu Intae Hwang 《Wireless Personal Communications》2014,75(1):775-797
The analysis and design of relay protocols is a hot issue in 3GPP Long Term Evolution—Advanced. In this paper, we discuss interference cancellation in a multiuser MIMO environment using Amplify-and-Forward (AF), Decode-and-Forward (DF) and De-Modulate-and-Forward (DMF) as relay protocols, and using Thomilson Harashima Precoding and Dirty Paper Coding as precoding techniques, with Zero-Forcing, Minimum Mean Square Error, Successive Interference Cancellation and Ordered Successive Interference Cancellation detection techniques. By using a combination of classical precoding schemes and detection techniques with weighted matrix, we propose a new interference cancellation technique that is capable of cancelling interference. The interference cancellation is managed by AF, DF and DMF relay node protocols and the interference free codeword is transmitted to the selected User Equipment. The proposed algorithm when used with DMF protocol shows best performance, compared to the conventional system or the no-relay system case, it gives best performance. The observation results shows that DMF protocol gives the best results for BER and Throughput performance in a high interference environment. 相似文献