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1.
Haus H.A. Khatri F.I. Wong W.S. Ippen E.P. Tamura K.R. 《Quantum Electronics, IEEE Journal of》1996,32(6):917-924
The interaction of a soliton of the Nonlinear Schrodinger Equation (NSE) with a weak sinusoidal wave packet is treated analytically. The second-order soliton solution containing the original soliton and a perturbing soliton is expanded to first order in the amplitude of the perturbating soliton. From this expansion, one obtains the associate function of Gordon (1992) and a continuous change of position and phase of the perturbed soliton. One finds that the soliton experiences a second-order change of velocity under the influence of the perturbation. This result is then used to derive the displacement due to a wave packet of general shape, which is also confirmed by computer simulation 相似文献
2.
Augmenting a conceptual model with geospatiotemporal annotations 总被引:1,自引:0,他引:1
Khatri V. Ram S. Snodgrass R.T. 《Knowledge and Data Engineering, IEEE Transactions on》2004,16(11):1324-1338
While many real-world applications need to organize data based on space (e.g., geology, geomarketing, environmental modeling) and/or time (e.g., accounting, inventory management, personnel management), existing conventional conceptual models do not provide a straightforward mechanism to explicitly capture the associated spatial and temporal semantics. As a result, it is left to database designers to discover, design, and implement - on an ad hoc basis - the temporal and spatial concepts that they need. We propose an annotation-based approach that allows a database designer to focus first on nontemporal and nongeospatial aspects (i.e., "what") of the application and, subsequently, augment the conceptual schema with geospatiotemporal annotations (i.e., "when" and "where"). Via annotations, we enable a supplementary level of abstraction that succinctly encapsulates the geospatiotemporal data semantics and naturally extends the semantics of a conventional conceptual model. An overarching assumption in conceptual modeling has always been that expressiveness and formality need to be balanced with simplicity. We posit that our formally defined annotation-based approach is net only expressive, but also straightforward to understand and implement. 相似文献
3.
Zhang Ke Mao Yuming Leng Supeng Maharjan Sabita Vinel Alexey Zhang Yan 《Mobile Networks and Applications》2019,24(3):1003-1014
Mobile Networks and Applications - Mobile Edge Computing (MEC) is a promising solution to improve vehicular services through offloading computation to cloud servers in close proximity to mobile... 相似文献
4.
Sepsis has recently been defined as life-threatening organ dysfunction caused by the dysregulated host response to an ongoing or suspected infection. To date, sepsis continues to be a leading cause of morbidity and mortality amongst hospitalized patients. Many risk factors contribute to development of sepsis, including pain-relieving drugs like opioids, which are frequently prescribed post-operatively. In light of the opioid crisis, understanding the interactions between opioid use and the development of sepsis has become extremely relevant, as opioid use is associated with increased risk of infection. Given that the intestinal tract is a major site of origin of sepsis-causing microbes, there has been an increasing focus on how alterations in the gut microbiome may predispose towards sepsis and mediate immune dysregulation. MicroRNAs, in particular, have emerged as key modulators of the inflammatory response during sepsis by tempering the immune response, thereby mediating the interaction between host and microbiome. In this review, we elucidate contributing roles of microRNA 146 in modulating sepsis pathogenesis and end with a discussion of therapeutic targeting of the gut microbiome in controlling immune dysregulation in sepsis. 相似文献
5.
Fracture toughness is the ability of a component containing a flow to resist fracture. In the current study, the Ball indentation (BI) test technique, which is well acknowledged as an alternative approach to evaluate mechanical properties of materials due to its semi-nondestructive, fast, and high accurate qualities is used to estimate damage and the fracture toughness for copper samples subjected to varying levels of creep and fatigue. The indentation fracture toughness shows the degradation of Cu samples when they are subjected to different creep conditions. Axial fatigue cycling increases the strength at the mid-gauge section compared to other regions of the samples due to initial strain hardening. The advancement of indentation depth with indentation fatigue cycles experiences transient stage, i.e., jump in indentation depth has been observed, which may be an indication of failure and followed by a steady state with almost constant depth propagation with indentation cycles. 相似文献
6.
This paper examines the reaction pathways and the nature of active sites for CO hydrogenation in general and C2+ oxygenate synthesis over Rh catalysts in particular. 相似文献
7.
The effect of standard heat treatment on the microstructure and mechanical properties of Ni–Fe base super-alloy, Inconel 718 was studied by optical microscopy and ball indentation technique (BIT) using small amount of specimen. In order to get good ductility, good formability, yield, tensile and creep rupture, as-received material was given the standard heat treatment, viz solution treatment at two temperatures 940 °C and 1040 °C for1 h and water quenched (WQ) followed by aging treatment at 720 °C for 8 h. and furnace cooling (FC). The BIT has revealed that the strengths for as-received material are maximum compared to other heat-treated materials. After solution treatment there has been a radical decline in strength. But the ageing causes a significant enhancement of strength. Optical microscopy studies supported the obtained BIT results. γ″-phase is the basic strengthening phase in 718 alloys. 相似文献
8.
Grigoriy Sereda Taejin Kim Aubrey Jones Hari Khatri Christopher L. Marshall H. Subramanian Ranjit T. Koodali 《Catalysis Letters》2011,141(8):1086-1096
Abstract
Catalytic performance of solid supported monovanadate catalysts toward oxidation of propane is significantly affected by the templating effect of: (1) pretreatment of the solid support with calixarene derivatives before deposition of ammonium vanadate, (2) direct deposition of vanadyl phthalocyanine as the vanadate precursor. This effect is believed to be linked to the accessibility of the active sites, and was studied in comparison with a reference mesoporous support. 相似文献9.
To date, all analyses of laminated conical shells have been undertaken using constant stiffness coefficients in the laminate constitutive equations. In this paper, it is shown that the geometry of a conical surface actually renders the stiffness coefficients a function of circumferential location; they are not strictly constant, as has previously been assumed. The inclusion of this geometric complicating effect in a static or dynamic analysis will add considerably to the complication and cost of a solution scheme, yet may or may not have a significant effect on the end result. A brief study is undertaken here to help resolve this dilemma, and to assess whether a particular cone geometry should be modelled using variable, or constant, stiffness coefficients in the laminae constitutive relationships. 相似文献
10.
SC Sharma SS Sangwam RC Siwach R Aggarwal CR Khatri VK Govila AK Sood 《Canadian Metallurgical Quarterly》1994,18(2):122-125
Rural schoolchildren between the ages of 6 and 18 years were screened for residual paralysis following poliomyelitis; 503 (0.85%) out of a total of 58,592 were victims. Of these, only 16 (3.8%) had received poliomyelitis vaccine, while the remainder had not been immunised. The disease had occurred before the age of 4 years in nearly 90%, the lower limbs being affected (98%) more often than the upper (2%). In the lower limbs, the quadriceps, hip adductors and tibialis anterior were frequently affected. The muscles supplied by the L4 and L5 spinal segments were most commonly involved, while those supplied by L1 and S3 were least. Some order does exist in the apparently irregular distribution of paralysis after poliomyelitis. 相似文献