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91.
EB Poluéktova NK Khitrov VI Andreev SG Pak BK Danilkin 《Canadian Metallurgical Quarterly》1997,69(11):14-16
Changes in the activity of acid phosphatase (AP) and its isoenzymes (tartrate-insensitive AP and formalin-insensitive AP) were investigated in patients with food poisoning in the course of the disease. The activity of AP and its isoenzymes in the serum started to grow in early convalescence and reached maximum in late convalescence. Total activity of AP in food toxic infections consists primarily of the activity of its platelet fraction. AP activity may serve as an additional criterion to predict vascular platelet involvement of hemostasis. 相似文献
92.
To advance the mathematical and computational treatments of mixed boundary value problems involving multilayered media, a new derivation of the fundamental Green’s functions for the elastodynamic problem is presented. By virtue of a method of displacement potentials, it is shown that there is an elegant mathematical structure underlying this class of three-dimensional elastodynamic problems which warrant further attention. Constituted by proper algebraic factorizations, a set of generalized transmission-reflection matrices and internal source fields that are free of any numerically unstable exponential terms common in past solution formats are proposed for effective computations of the potential solution. To encompass both elastic and viscoelastic cases, point-load Green’s functions for stresses and displacements are generalized into complex-plane line-integral representations. An accompanying rigorous treatment of the singularity of the fundamental solution for arbitrary source-receiver locations via an asymptotic decomposition of the transmission-reflection matrices is also highlighted. 相似文献
93.
SO Schoenberg MV Knopp M Bock F Kallinowski A Just M Essig H Hawighorst I Zuna L Schad JR Allenberg G van Kaick 《Canadian Metallurgical Quarterly》1997,37(8):651-662
PURPOSE: To evaluate the use of high-temporal resolution cine MR phase-contrast flow measurements for assessment of flow dynamics in renal artery stenosis (RAS). MATERIAL AND METHODS: In a dog model, cine MR flow measurements were validated by comparing the MR flow data to an invasive transit-time ultrasound reference technique for different degrees of RAS. Cardiac-gated MR flow curves were recorded in 56 renal arteries of 28 patients with a temporal resolution of at least 32 ms. In all cases RAS was confirmed by digital subtraction angiography (DSA). Abnormalities of flow dynamics were assessed in the calculated flow curves using the MR parameters mean flow, maximum velocity, and time to systolic maximum. RESULTS: By means of the MR blood flow parameters high-grade stenoses (> 50%, n = 23) were detected with sensitivity of 100% and specificity of 94% with reference to DSA. The overall differentiation between stenoses (n = 37) and non-stenosed vessels (n = 19) revealed a sensitivity of 87% and a specificity of 100%. CONCLUSION: Analysis of cardiac-gated MR flow curves provides a non-invasive method to assess the hemodynamic significance of RAS and thus allows a functional evaluation in relation to the morphologic characteristics of the stenosis. 相似文献
94.
Sunil Pak Duck Young Ku Dong-Keun Oh Hogun Jhang Duck-Hoi Kim Mun-Seong Cheon Chang Rae Seon Hyeon Gon Lee Spencer Pitcher 《Fusion Engineering and Design》2011,86(9-11):1877-1881
Electromagnetic (EM) loads due to eddy current and halo current during plasma disruptions are evaluated for the ITER diagnostic upper port plug. To reduce strong EM loads acting on the port plug fixed to the vacuum vessel like a cantilever beam, three design options have been considered: removal of the diagnostic first wall, slitting of the diagnostic shield module and recess of the port plug. The main focus of the present study is to examine the efficacy of these options in terms of EM loads on the upper port plug. It is found that making slits is more effective than removing the first wall. It is also shown that the upper port plug needs to be recessed to reduce the EM load induced by halo current. 相似文献
95.
96.
Jong-Jin Pak Yong-Soo Jeong Soon-Jae Tae Dong-Sik Kim Yun-Yong Lee 《Metallurgical and Materials Transactions B》2005,36(4):489-493
The equilibrium solubility of titanium and nitrogen in Fe-Ni melts was measured in the presence of pure solid TiN under various
nitrogen pressures in the temperature range of 1843 to 1923 K. The activity coefficients of titanium and nitrogen relative
to a 1 mass pct standard state in liquid iron were calculated from the experimental results for Fe-Ni alloys of nickel contents
up to 30 mass pct. Nickel decreases the activity coefficient of titanium, but it increases the activity coefficient of nitrogen
in an Fe-Ni-Ti-N melt. Therefore, the effect of nickel on the solubility product of TiN is not significant. The first- and
second-order interaction parameters of nickel on titanium (e
Ti
Ni
and r
Ti
Ni
, respectively) were determined to be −0.0115 and 0 at 1873 K, respectively. Similarly, the interaction parameters of nickel
on nitrogen (e
N
Ni
and r
N
Ni
, respectively) were determined to be 0.012 and 0, respectively, at 1873 K. The temperature dependence of these interaction
parameters was also determined. 相似文献
97.
Joobong Hyun Dong‐Choon Hwang Dong‐Hak Shin Byung‐Gook Lee Eun‐Soo Kim 《ETRI Journal》2009,31(2):105-110
In this paper, we propose a curved projection integral imaging system to improve the horizontal and vertical viewing angles. The proposed system can be easily implemented by additional use of a large‐aperture convex lens in conventional projection integral imaging. To obtain the simultaneous display of 3D images through real and virtual image fields, we propose a computer‐generated pickup method based on ray optics and elemental images, which are synthesized for the proposed system. To show the feasibility of the proposed system, preliminary experiments are carried out. Experimental results indicate that our system improves the viewing angle and displays 3D images simultaneously in real and virtual image fields. 相似文献
98.
99.
Tjhung T.T. Choon Tiong Ng Chun Sum Ng 《Vehicular Technology, IEEE Transactions on》1995,44(1):140-145
Reed Solomon codes with interleaving are used in a binary FM transmission affected by Rayleigh fading as encountered in land mobile radio. A new decoding algorithm is proposed which can be implemented in simple hardware. The error performance of the binary FM system with the RS code with one and two degrees of interleaving is measured. A significant reduction of error rate floor as a function of fading speed is noted and discussed 相似文献
100.
To analyze the withdrawal force curve in the wetting balance curve, wetting balance tests using the 63Sn-37Pb and 96.5Sn-3.6Ag eutectic solders were conducted by varying the immersion speed, sample perimeter, and solder temperature. The mechanism of the withdrawal force curve was reviewed and a new method for calculating the surface tension of solders using the withdrawal force curve was introduced. The results showed that the maximum point of the withdrawal force curve is generated when the sliding solder meets the bottom corners of a sample and the contact angle is reduced to zero. The maximum withdrawal force subtracted by end force can be expressed using force balance equation as F=pγ. Therefore, the surface tension of the solder can be calculated by dividing the maximum withdrawal force by the sample parameter. 相似文献