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111.
We consider infrastructure-based mobile networks that are assisted by a single relay transmission where both the downstream destination and relay nodes are mobile. Selecting the optimal transmission path for a destination node requires up-to-date link quality estimates of all relevant links. If the relay selection is based on link quality measurements, the number of links to update grows quadratically with the number of nodes, and measurements need to be updated frequently when nodes are mobile. In this paper, we consider a location-based relay selection scheme where link qualities are estimated from node positions; in the scenario of a node-based location system such as GPS, the location-based approach reduces signaling overhead, which in this case only grows linearly with the number of nodes. This paper studies these two relay selection approaches and investigates how they are affected with varying information update interval, node mobility, location inaccuracy, and inaccurate propagation model parameters. Our results show that location-based relay selection performs better than SNR-based relay selection at typical levels of location error when medium-scale fading can be neglected or accurately predicted. 相似文献
112.
Abstract and Key Results
相似文献
▪ | Subsidiary managers are faced with complex managerial roles involving both the interests of the multinational corporation (MNC) and the subsidiary. We suggest complex roles are best fulfilled when managers develop dual organizational identification towards both entities. |
▪ | Based on a conceptualization of dual organizational identification in terms of relative magnitude, we test the effect of dual identification on subsidiary manager roles and role conflict. |
▪ | Results indicate that high identification with both entities is associated with high role fulfillment and that similarity in organizational identities directly affects role conflict. |
113.
Bastiaans MJ Alieva T 《Journal of the Optical Society of America. A, Optics, image science, and vision》2007,24(4):1053-1062
Based on the eigenvalues of the ray transformation matrix, a classification of ABCD systems is proposed and some nuclei (i.e., elementary members) in each class are described. In the one-dimensional case, possible nuclei are the magnifier, the lens, and the fractional Fourier transformer. In the two-dimensional case we have-in addition to the obvious concatenations of one-dimensional nuclei-the four combinations of a magnifier or a lens with a rotator or a shearing operator, where the rotator and the shearer are obviously inherently two-dimensional. Any ABCD system belongs to one of the classes described in this paper and is similar (in the sense of matrix similarity of the ray transformation matrices) to the corresponding nucleus. Knowledge of a nucleus may be helpful in finding eigenfunctions of the corresponding class of first-order optical systems: one only has to find eigenfunctions of the nucleus and to determine how these functions propagate through a first-order optical system. 相似文献
114.
Alieva T Bastiaans MJ 《Journal of the Optical Society of America. A, Optics, image science, and vision》2007,24(11):3658-3665
We provide a general expression and different classification schemes for the general two-dimensional canonical integral transformations that describe the propagation of coherent light through lossless first-order optical systems. Main theorems for these transformations, such as shift, scaling, derivation, etc., together with the canonical integral transforms of selected functions, are derived. 相似文献
115.
Kastler M Pisula W Davies RJ Gorelik T Kolb U Müllen K 《Small (Weinheim an der Bergstrasse, Germany)》2007,3(8):1438-1444
A high-yielding synthesis afforded a hexa-peri-hexabenzocoronene carrying acrylate units at the end of six attached alkyl spacers. The polymerization of these acrylate moieties could be initiated with thermal energy and through direct photoactivation without the addition of a photoinitiator. This allowed the organization of the liquid-crystalline material to be fixed in either the crystalline state or the mesophase, which preserved the organization in the respective phase. The use of a focused synchrotron beam permitted selected regions of a thin film to be rendered insoluble. After "developing" the film in this lithographic process by dissolving the soluble, unpolymerized material, defined nano-objects remained on the substrate. In addition, the pronounced aromatic pi stacking of the novel material allows an organization in mesoporous membranes that could be fixed by thermal crosslinking. After the removal of the inorganic template, mechanically stable nanotubes were obtained, which were characterized by different microscopy techniques. 相似文献
116.
Ibragim E Suleimenov Vladimir B Sigitov Sarkyt E Kudaibergenov Alexander G Didukh Tatiana S Fryasinova Esen A Bekturov 《Polymer International》2001,50(2):194-196
The behaviour of polyelectrolyte gel under the influence of combined electric and magnetic fields has been studied. It is shown that the rate of gel contraction stimulated by an electric field can be significantly changed under the action of an external magnetic field. A qualitative interpretation of the observed phenomenon is given. © 2001 Society of Chemical Industry 相似文献
117.
Hen Haddad Sharon Etzion Tatiana Rabinski Rivka Ofir Danielle Regev Yoram Etzion Jacob Gopas Aviv Goldbart 《International journal of molecular sciences》2021,22(21)
Obstructive sleep apnea syndrome (OSAS) patients suffer from cardiovascular morbidity, which is the leading cause of death in this disease. Based on our previous work with transformed cell lines and primary rat cardiomyocytes, we determined that upon incubation with sera from pediatric OSAS patients, the cell’s morphology changes, NF-κB pathway is activated, and their beating rate and viability decreases. These results suggest an important link between OSAS, systemic inflammatory signals and end-organ cardiovascular diseases. In this work, we confirmed and expanded these observations on a new in vitro system of beating human cardiomyocytes (CM) differentiated from human embryonic stem cells (hES). Our results show that incubation with pediatric OSAS sera, in contrast to sera from healthy children, induces over-expression of NF-κB p50 and p65 subunits, marked reduction in CMs beating rate, contraction amplitude and a strong reduction in intracellular calcium signal. The use of human CM cells derived from embryonic stem cells has not been previously reported in OSAS research. The results further support the hypothesis that NF-κB dependent inflammatory pathways play an important role in the evolution of cardiovascular morbidity in OSAS. This study uncovers a new model to investigate molecular and functional aspects of cardiovascular pathology in OSAS. 相似文献
118.
119.
The polymer poly(vinylidene fluoride) (PVDF) was irradiated with X-rays produced by a nonmonochromatic (MgKα) source and the structural and electronic PVDF surface modifications were studied by X-ray photoelectron spectroscopy (XPS). Changes in the shape and intensity of the C1s and F1s lines show that a PVDF degradation consisting of the polymer defluorination takes place. © 1998 John Wiley & Sons, Inc. J Appl Polym Sci 67:2125–2129, 1998 相似文献
120.
Grigory Kovtun Tatiana Kameneva Serhy Hladyi Mykhailo Starchevsky Yury Pazdersky Igor Stolarov Michael Vargaftik Ilya Moiseev 《Advanced Synthesis \u0026amp; Catalysis》2002,344(9):957-964
Redox disproportionation of benzyl alcohol to benzaldehyde and toluene catalysed by the Pd561phen60(OAc)180 (phen=1,10‐phenanthroline) giant cluster 1 under anaerobic conditions was found, whereas in an O2 atmosphere cluster 1 catalyses the oxidation of benzyl alcohol to benzaldehyde and inhibits further oxidation of the latter. A study of the AIBN‐initiated and non‐initiated oxidation of benzyl alcohol, sec‐butyl alcohol and styrene in the presence of cluster 1 revealed that cluster 1 performs three functions in the oxidation reactions: 1) catalysis of polar oxidation of the substrates with O2, 2) termination of the chains of radical oxidation, and 3) catalysis of redox disproportionation. 相似文献