http://chineseinput.net/에서 pinyin(병음)방식으로 중국어를 변환할 수 있습니다.
변환된 중국어를 복사하여 사용하시면 됩니다.
Li, Hao Leo,Hu, Aiguo Patrick,Covic, Grant Anthony The Korean Institute of Power Electronics 2011 JOURNAL OF POWER ELECTRONICS Vol.11 No.3
This paper utilizes free oscillation and energy injection principles to generate and control the high frequency current in the primary track of a contactless power transfer system. Here the primary power inverter maintains natural resonance while ensuring near constant current magnitude in the primary track as required for multiple independent loads. Such energy injection controllers exhibit low switching frequency and achieve ZCS (Zero Current Switching) by detecting the high frequency current, thus the switching stress, power losses and EMI of the inverter are low. An example full bridge topology is investigated for a contactless power transfer system with multiple pickups. Theoretical analysis, simulation and experimental results show that the proposed system has a fast and smooth start-up transient response. The output track current is fully controllable with a sufficiently good waveform for contactless power transfer applications.
Power Control in Uplink and Downlink CDMA Systems with Multiple Flow Types
Li Yun,Ephremides Anthony The Korea Institute of Information and Commucation 2006 Journal of communications and networks Vol.8 No.3
We consider a power controlled code division multiple access (CDMA) system with multiple flow types. At each of the N nodes, there are F flow types with different signal-to-interference-and-noise-ratio (SINR) requirements. To keep the complexity of the transmitter low, we assume that each node uses the same power level for all its flows. The single flow case has been fully solved and is well-understood. We concentrate on the multiple flow case, and use a novel and different approach. For the uplink problem with N = 2 and F arbitrary, the necessary and sufficient conditions to have a solution are found and proved. For the general N > 1 uplink problem, we provide a necessary condition for the problem to have a solution and an iterative algorithm to find the optimum solution. For the downlink case with F > 1 some properties of the optimal sequences are obtained.
Li, Suzhao,Neff, C. Preston,Barber, Kristina,Hong, Jaewoo,Luo, Yuchun,Azam, Tania,Palmer, Brent E.,Fujita, Mayumi,Garlanda, Cecilia,Mantovani, Alberto,Kim, Soohyun,Dinarello, Charles Anthony National Academy of Sciences 2015 PROCEEDINGS OF THE NATIONAL ACADEMY OF SCIENCES OF Vol.112 No.8
<P><B>Significance</B></P><P>Interleukin-1 family members are highly inflammatory but IL-37 member broadly suppresses inflammation and specific immunity. Initially, the mechanism of this suppression was shown to be via translocation to the nucleus following cleavage of the precursor by intracellular caspase-1. We now show that recombinant forms of IL-37 limit inflammation by extracellular binding to surface receptors but require the IL-1 family decoy receptor IL-1R8. Unexpectedly, picomolar concentrations of the IL-37 precursor optimally suppress IL-1β, IL-6, and TNFα production from human blood M1 macrophages, suggesting a unique function for a coreceptor function of IL-1R8. Assessment of IL-37 as well as IL-1R8 levels may provide previously unidentified insights into how the host limits inflammation.</P><P>Similar to IL-1α and IL-33, IL-1 family member IL-37b translocates to the nucleus and is associated with suppression of innate and adaptive immunity. Here we demonstrate an extracellular function of the IL-37 precursor and a processed form. Recombinant IL-37 precursor reduced LPS-induced IL-6 by 50% (<I>P</I> < 0.001) in highly inflammatory human blood-derived M1 differentiated macrophages derived from selective subjects but not M2 macrophages. In contrast, a neutralizing monoclonal anti–IL-37 increased LPS-induced IL-6, TNFα and IL-1β (<I>P</I> < 0.01). The suppression by IL-37 was consistently observed at low picomolar but not nanomolar concentrations. Whereas LPS induced a 12-fold increase in TNFα mRNA, IL-37 pretreatment decreased the expression to only 3-fold over background (<I>P</I> < 0.01). Mechanistically, LPS-induced p38 and pERK were reduced by IL-37. Recombinant IL-37 bound to the immobilized ligand binding α-chain of the IL-18 receptor as well as to the decoy receptor IL-1R8. In M1 macrophages, LPS increased the surface expression of IL-1R8. Compared with human blood monocytes, resting M1 cells express more surface IL-1R8 as well as total IL-1R8; there was a 16-fold increase in IL-1R8 mRNA levels when pretreated with IL-37. IL-37 reduced LPS-induced TNFα and IL-6 by 50–55% in mouse bone marrow-derived dendritic cells, but not in dendritic cells derived from IL-1R8–deficient mice. In mice subjected to systemic LPS-induced inflammation, pretreatment with IL-37 reduced circulating and organ cytokine levels. Thus, in addition to a nuclear function, IL-37 acts as an extracellular cytokine by binding to the IL-18 receptor but using the IL-1R8 for its anti-inflammatory properties.</P>
Collapse of Magnetised, Singular Isothermal Toroids
ALLEN ANTHONY,SHU FRANK,LI ZHI- YUN The Korean Astronomical Society 2001 Journal of The Korean Astronomical Society Vol.34 No.4
This poster summarizes numerical collapse calculations of non-rotating and rotating singular, isothermal toroids that employed the zeus2d (Norman and Stone 1992) magnetohydrodynamics package. In the non-rotating collapse calculations, it is seen that infall proceeds at a constant rate and magnetically supported, high density pseudo-disks form in the equatorial plane. With rotating clouds, however, toroidal magnetic fields grow as infall proceeds, teaming with angular momentum to slow the inflow to the center and generate outflow.
Hao Leo Li,Aiguo Patrick Hu,Grant Anthony Covic 전력전자학회 2011 JOURNAL OF POWER ELECTRONICS Vol.11 No.3
This paper utilizes free oscillation and energy injection principles to generate and control the high frequency current in the primary track of a contactless power transfer system. Here the primary power inverter maintains natural resonance while ensuring near constant current magnitude in the primary track as required for multiple independent loads. Such energy injection controllers exhibit low switching frequency and achieve ZCS (Zero Current Switching) by detecting the high frequency current, thus the switching stress, power losses and EMI of the inverter are low. An example full bridge topology is investigated for a contactless power transfer system with multiple pickups. Theoretical analysis, simulation and experimental results show that the proposed system has a fast and smooth start-up transient response. The output track current is fully controllable with a sufficiently good waveform for contactless power transfer applications.
Zhaobing Liu,Yanle Li,Paul Anthony Meehan 한국정밀공학회 2013 International Journal of Precision Engineering and Vol. No.
Incremental sheet forming (ISF) has demonstrated its high potential to shape complex three-dimensional components without using specific tooling, thus enabling product customization, cost reduction and efficiencies. This paper presents an experimental campaign to investigate AA7075-O aluminum alloy sheet forming using single point incremental forming (SPIF) technology and understand the forming process mechanism. Firstly, tensile tests were carried out to characterize the mechanical properties of AA7075-O sheets with three different thicknesses. Then, the effects of tool path types with different incremental steps on the maximum part draw angle and the successful part height were evaluated to clarify the formability. Additionally, a fracture forming limit diagram was developed to give the design limits for strain. Finally, the trends in forming forces were analyzed considering the influence of different draw angles,sheet thicknesses, step-down sizes and sheet orientations. Experimental results showed that formability is affected by the part draw angle and incremental steps of the tool path. However, the likelihood of successful forming also depends on other geometrical design parameters such as the part height. In addition, the influences of process parameters on tool forces provide further insights into the deformation mechanics of AA7075-O sheets. The slope of the force curve after the peak value can be identified as a forming failure prediction indicator regardless of the tool path types when using a truncated cone as a benchmark. Also the influence of sheet orientations on forming forces was investigated in SPIF. The vertical forming force is found to be smaller in a sheet orientation 45to the rolling direction than that of a sheet orientation 0 for three different sheet thicknesses.
Accelerated Cardiac Diffusion Tensor Imaging Using Joint Low-Rank and Sparsity Constraints
Ma, Sen,Nguyen, Christopher T.,Christodoulou, Anthony G.,Luthringer, Daniel,Kobashigawa, Jon,Lee, Sang-Eun,Chang, Hyuk-Jae,Li, Debiao IEEE 2018 IEEE Transactions on Biomedical Engineering Vol.65 No.10
<P>Objective: The purpose of this paper is to accelerate cardiac diffusion tensor imaging (CDTI) by integrating low-rankness and compressed sensing. Methods: Diffusion-weighted images exhibit both transform sparsity and low-rankness. These properties can jointly be exploited to accelerate CDTI, especially when a phase map is applied to correct for the phase inconsistency across diffusion directions, thereby enhancing low-rankness. The proposed method is evaluated both ex vivo and in vivo, and is compared to methods using either a low-rank or sparsity constraint alone. Results: Compared to using a low-rank or sparsity constraint alone, the proposed method preserves more accurate helix angle features, the transmural continuum across the myocardium wall, and mean diffusivity at higher acceleration, while yielding significantly lower bias and higher intraclass correlation coefficient. Conclusion: Low-rankness and compressed sensing together facilitate acceleration for both ex vivo and in vivo CDTI, improving reconstruction accuracy compared to employing either constraint alone. Significance: Compared to previous methods for accelerating CDTI, the proposed method has the potential to reach higher acceleration while preserving myofiber architecture features, which may allow more spatial coverage, higher spatial resolution, and shorter temporal footprint in the future.</P>