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1.
Sheen D.M. Ali S.M. Oates D.E. Withers R.S. Kong J.A. 《Applied Superconductivity, IEEE Transactions on》1991,1(2):108-115
A method for the calculation of the current distribution, resistance, and inductance matrices for a system of coupled superconducting transmission lines having finite rectangular cross-section is presented. These calculations allow accurate characterization of both high-T c and low-T c superconducting strip transmission lines. For a single stripline geometry with finite ground planes, the current distribution, resistance, inductance, and kinetic inductance are calculated as functions of the penetration depth for various film thicknesses. These calculations are then used to determine the penetration depth for Nb, NbN, and YBa2Cu3O7-x superconducting thin films from the measured temperature dependence of the resonant frequency of a stripline resonator. The calculations are also used to convert measured temperature dependence of the quality factor to the intrinsic surface resistance as a function of temperature for an Nb stripline resonator 相似文献
2.
This paper derives two fuzzy financial profitability models, namely, a least cost solution model and a cost-benefit analysis model, to evaluate the fuzzy financial profitability of load management alternatives. A straightforward vertex parameters' fuzzy mathematics operation using the function principle is derived as an alternative to the traditional extension principle and is applied to evaluate a number of different financial decision indexes. Compared to the extension principle, the function principle is simple to implement and is conceptually straightforward. The geometric moments of the fuzzy financial indexes are established in order to determine their relative ranking as part of a decision-making process. The performances of the proposed fuzzy financial models are verified by considering their application to two practical load management programs in Taiwan, namely, a cooling energy storage air conditioner and a cogeneration project. These investigations not only confirm that the results of the fuzzy financial models are consistent with those of the conventional crisp models but also demonstrate that the proposed models are more flexible, intelligent, and computationally efficient compared to the extension principle fuzzy mathematics approach. The developed models represent readily implemented possibility analysis tools for use in the arena of uncertain financial decision-making. 相似文献
3.
4.
Szu-I Yeh Wei-Feng Fang Horn-Jiunn Sheen Jing-Tang Yang 《Microfluidics and nanofluidics》2013,14(5):785-795
The influence of identical and distinct surface tensions on the coalescence and mixing of droplets after a direct collision on a wettability gradient surface (made from a self-assembled monolayer, SAM technique) was investigated. The results indicate that their mixing is driven sequentially by interior convection and diffusion; the convection endures less than 100 ms but dominates more than 60 % of the mixing. If the stationary droplet has a large surface tension (73.28 mN × m?1), whether the moving droplet has a large surface tension (73.28 mN × m?1) or a small surface tension (38.63 mN × m?1), the mushroom-shaped mixing pattern is generated within the coalesced droplet that enhances the convective mixing and also significantly enlarges the interface for mass diffusion. The mixing index of these two cases was greater than 0.8 at 120 s after the collision. For the cases in which the stationary droplet with a small surface tension collided by the moving droplet with a large surface tension, a mixing pattern with a round-head shape developed, which was insufficient to benefit the mixing. When the stationary and moving droplets both had small surface tension, the moving droplet was unable to merge with stationary droplet and had poor mixing quality due to the small surface Gibbs energy of both stationary and moving droplets. For the collision of droplets of identical surface tension, the surface tension affects the coalescence behavior; for the collision of droplets with distinct surface tension, the coalescence behavior and mixing quality depend on the colliding arrangement of stationary and moving droplets. 相似文献
5.
Dong-Pyoung Sheen Tae-geun Son Dae-Kwang Myung Cheolho Ryu Sang Hun Lee Kunwoo Lee Tae Jung Yeo 《Computer aided design》2010,42(8):720-730
A simplified geometric model with lower dimensionality, such as a mid-surface model, is often preferred over a detailed solid model for the analysis process, if the analysis results are not seriously impacted. In order to derive a mid-surface model from a thin-walled solid model, in this paper, we propose a novel approach called the solid deflation method. In this method, a solid model is assumed to be created by using air to inflate a shell that comprises the surface of the solid model. First, the model is simplified by the removal of any detailed features whose absence would not alter its overall shape. Next, the solid model itself can be converted into a degenerate solid model with zero thickness. Finally, a surface model is generated by splitting large faces paired in the thinned solid model, selecting one face per pair for creating a sheet model, and sewing the selected faces. Using this method, a more practical and usable mid-surface model can be very efficiently generated from a solid model because it can circumvent not only the tedious trimming and extension processes of the medial axis transformation method but also the time-consuming patch joining process of the mid-surface abstraction approach. 相似文献
6.
In this paper we solve linear parabolic problems using the three stage noble algorithms. First, the time discretization is
approximated using the Laplace transformation method, which is both parallel in time (and can be in space, too) and extremely
high order convergent. Second, higher-order compact schemes of order four and six are used for the the spatial discretization.
Finally, the discretized linear algebraic systems are solved using multigrid to show the actual convergence rate for numerical
examples, which are compared to other numerical solution methods. 相似文献
7.
Mang Ou-Yang Chin-Shown Sheen Jin-Shown Shie 《IEEE transactions on instrumentation and measurement》1998,47(2):403-408
Obtaining device parameters of thermal microsensors is essential for evaluating their performances and simulation modeling. We report an AC electrical method for extracting these parameters experimentally with relatively simple instrumentation. The basic parameters of resistive microsensors, the resistance, temperature coefficient of resistance, thermal capacitance, and conductance, are derivable from the second harmonic signal of the output voltage induced by a sinusoidal driving current. The results are compared with other methods 相似文献
8.
Ying-Hsien Huang Ho-Chang Kuo Fu-Chen Huang Hong-Ren Yu Kai-Sheng Hsieh Ya-Ling Yang Jiunn-Ming Sheen Sung-Chou Li Hsing-Chun Kuo 《International journal of molecular sciences》2016,17(5)
Kawasaki disease (KD) is a type of systemic vasculitis that primarily affects children under the age of five years old. For sufferers of KD, intravenous immunoglobulin (IVIG) has been found to successfully diminish the occurrence of coronary artery lesions. Anemia is commonly found in KD patients, and we have shown that in appropriately elevated hepcidin levels are related to decreased hemoglobin levels in these patients. In this study, we investigated the time period of anemia and iron metabolism during different stages of KD. A total of 100 patients with KD and 20 control subjects were enrolled in this study for red blood cell and hemoglobin analysis. Furthermore, plasma, urine hepcidin, and plasma IL-6 levels were evaluated using enzyme-linked immunosorbent assay in 20 KD patients and controls. Changes in hemoglobin, plasma iron levels, and total iron binding capacity (TIBC) were also measured in patients with KD. Hemoglobin, iron levels, and TIBC were lower (p < 0.001, p = 0.009, and p < 0.001, respectively) while plasma IL-6 and hepcidin levels (both p < 0.001) were higher in patients with KD than in the controls prior to IVIG administration. Moreover, plasma hepcidin levels were positively and significantly correlated with urine hepcidin levels (p < 0.001) prior to IVIG administration. After IVIG treatment, plasma hepcidin and hemoglobin levels significantly decreased (both p < 0.001). Of particular note was a subsequent gradual increase in hemoglobin levels during the three weeks after IVIG treatment; nevertheless, the hemoglobin levels stayed lower in KD patients than in the controls (p = 0.045). These findings provide a longitudinal study of hemoglobin changes and among the first evidence that hepcidin induces transient anemia and hypoferremia during KD’s acute inflammatory phase. 相似文献
9.
Siyuan Zhou Shiowshuh Sheen Yu‐Hsin Pang LinShu Liu Kit L. Yam 《Journal of food science》2013,78(5):M725-M730
Salmonella contamination on raw shrimp is a big food safety concern in the United States currently. This research evaluated the inhibition effects of vapor phase thymol, modified atmosphere (MA), and their combination against Salmonella spp. on raw shrimp. Growth profiles of a Salmonella spp. cocktail (6 strains), inoculated onto the surface of raw shrimp, treated with vapor phase thymol at 3 levels (0, 0.8, and 1.6 mg/L), or MA (59.5% CO2 + 39.5% N2 + 1% O2), both alone and in combination, at 3 temperatures (8, 12, and 16 ºC), were determined. Lag time and maximum growth rate of Salmonella spp. under each treatment were obtained using Baranyi and Roberts models. Results indicated that both vapor phase thymol and MA treatments alone inhibited the growth potential of Salmonella spp. effectively, extending the lag time by 10% to 100% and reducing the maximum growth rate by 14% to 71% compared with controlled samples at experimental temperatures (8, 12, and 16 ºC). Combination treatments of vapor phase thymol and MA exhibited greater inhibition effectiveness than each individual treatment and a synergistic antimicrobial effectiveness could be observed on the lag time extension. To the maximum, at 12 ºC, lag time of Salmonella spp. was extended 59.6% more by the combination treatment of 0.8 mg/L thymol + MA (36.97 h) than those effects combined from 0.8 mg/L thymol treatment and MA treatment alone (23.16 h in total). This combination strategy could be potentially utilized for Salmonella inhibition during the long distance and temperature‐abused raw shrimp import process. Practical Application The vapor phase thymol + MA combination strategy could be potentially applied in temperature‐abused and long‐distance raw shrimp import process to retard the Salmonella spp. growth, therefore reducing its import rejection rate as well as enhancing its food safety level to the consumers’ concerns. 相似文献
10.