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991.
Yong Huo 《Journal of Zhejiang University. Science. B》2010,11(8):631-633
##正##Dr.Gruntzig et al.(1979) successfully completed the world's first percutaneous coronary intervention (PCI),a percutaneous transluminal coronary 相似文献
992.
Ling Xia Ying-lan Gong Xiu-wei Zhu Yu Zhang Qi Sun Heng-gui Zhang 《Journal of Zhejiang University. Science. B》2010,11(6):402-416
The aim of this study is to build two mathematical models of canine ionic currents specific to right atria and left atria.The canine left atria mathematical model was firstly modified from the Ramirez-Nattel-Courtemanche(RNC) model using the recently available experimental data of ionic currents and was further developed based on our own experimental data.A model of right atria was then built by considering the differences between right atria and left atria.The two developed models well reproduced the exper... 相似文献
993.
Qing-jun Liu Wei-wei Ye Hui Yu Ning Hu Li-ping Du Ping Wang 《Journal of Zhejiang University. Science. B》2010,11(5):323-331
Neurochip based on light-addressable potentiometric sensor(LAPS),whose sensing elements are excitable cells,can monitor electrophysiological properties of cultured neuron networks with cellular signals well analyzed.Here we report a kind of neurochip with rat pheochromocytoma(PC12) cells hybrid with LAPS and a method of de-noising signals based on wavelet transform.Cells were cultured on LAPS for several days to form networks,and we then used LAPS system to detect the extracellular potentials with signals d... 相似文献
994.
Su Ye Sohn Gi Young Jang Byung Min Choi 《Journal of Zhejiang University. Science. B》2010,11(7):539-541
Congenital atresia of the left main coronary artery is a rare occurrence, and surgical revascularizationbypass graft is required.
We here report a rare case of congenital coronary anomaly in an infant. A 10-month-old male infant was admitted to the hospital
with heart failure symptoms. Echocardiographic examinations revealed mitral valve regurgitation and ischemic changes of the
anterolateral papillary muscle and chordae. Coronary angiography showed atresia of the left main coronary artery with a severe
hypoplastic left anterior descending artery and a circumflex coronary artery. Unfortunately, sudden cardiac arrest occurred
after catheterization and the infant did not recover despite of immediate cardiopulmonary resuscitation. Further studies are
needed to find a newer diagnostic method to detect coronary anomaly in an infant, and coronary angiography, if necessary,
has to be performed very carefully. 相似文献
995.
This paper reports on the electromagnetic effects on the biological tissue surrounding a transcutaneous transformer for an
artificial anal sphincter. The coupling coils and human tissues, including the skin, fat, muscle, liver, and blood, were considered.
Specific absorption rate (SAR) and current density were analyzed by a finite-length solenoid model. First, SAR and current
density as a function of frequency (10–107 Hz) for an emission current of 1.5 A were calculated under different tissue thickness. Then relations between SAR, current
density, and five types of tissues under each frequency were deduced. As a result, both the SAR and current density were below
the basic restrictions of the International Commission on Non-Ionizing Radiation Protection (ICNIRP). The results show that
the analysis of these data is very important for developing the artificial anal sphincter system. 相似文献
996.
This study deals with the recycling of carbon steel slag (CSS) to produce self-consolidating concrete (SCC). Since the chemical composition of CSS is similar to that of Portland cement or blast furnace slag (BFS), it is expected to behave similarly. In the current study, the pozzolanic activity index of CSS is examined. Furthermore, the use of CSS as a pozzolanic material to partially replace Portland cement in the production of SCC is tested. We designed concrete mixtures with different water-to- cementitious material ratios (w/cm) keeping water and superplasticizer (SP) contents constant. Results showed that the design and performance of all the concrete mixtures used in this investigation were comparable to those of SCC and high performance con- crete (HPC). However, compared to ordinary plain concrete (OPC), the additional CSS content increases the setting time. In the CSS mixtures set for 90 d, compressive strengths of 86%, 134% and 121% were attained as compared to the control concrete; the corresponding w/cm ratios were 0.28, 0.32 and 0.40, respectively. Verifying the soundness of the SCC for meeting the criteria for HPC, the ultrasonic pulse velocity (UPV) of CSS was found to be comparable to that of ordinary concrete. In conclusion, the recycling of CSS can be advantageously employed in the production of SCC. 相似文献
997.
This study discusses a yard planning system,which considers various resources such as storage space,yard cranes,and traffic areas in container terminals.The system is based on the function for estimating resource requirements of yard plans.For a given yard plan,the proposed system allows planners to check the feasibility of the plan which requires a certain amount of workload of resources in related blocks during a planning horizon.The yard planning system in this study is aimed at balancing workloads among the blocks and providing the ability to modify current yard plans by detecting blocks and periods with overloaded workloads.The system implements its planning function in a distributed manner in which planners construct yard plans under their individual control and send and receive only limited necessary information for the negotiation. 相似文献
998.
Yang Gao 《浙江大学学报(A卷英文版)》2010,11(10):835-840
This paper deals with the combination of point phonon and phason forces applied in the interior of infinite planes and half-planes of 1D quasicrystal bi-materials. Based on the general solution of quasicrystals, a series of displacement functions are adopted to obtain Green's functions for infinite planes and bi-material planes composed of two half-planes in the closed form, when the two half-planes are supposed to be ideally bonded or to be in smooth contact. Since the physical quantities can be readily calculated without the need of performing any transform operations, Green's functions are very convenient to be used in the study of point defects and inhomogeneities in the quasicrystal materials. 相似文献
999.
The free vibration and transient wave in a prestressed Rayleigh-Timoshenko beam subject to arbitrary transverse forces are analyzed by the newly developed method of reverberation-ray matrix (MRRM). The effects of shear deformation and rotational inertia are taken into consideration. With a Fourier transform technique, the general wave solutions with two sets of unknown amplitude coefficients are obtained in the transformed domain for an unbonded prestressed beam under the action of arbitrary external excitations. From the coupling at joints and the compatibility of displacements in each member, the free and forced vibration responses of a beam with various boundary conditions are finally evaluated through certain numerical algorithms, Results are presented for a simply-supported beam subject to either a point fixed load or moving load. Good agreement with the finite element method (FEM) is obtained. The present work is instructive for high-speed railway bridge design and structural health monitoring. 相似文献
1000.
The objective of the present research is to investigate the relationship among tool wear, surface topography, and surface roughness when high-speed end milling Ti-6Al-4V alloy, and also to define an optimal flank wear criterion for the cutting tool to integrate tool life and the surface roughness requirements of the finish milling process. An annealed Ti-6Al-4V alloy was selected as the workpiece material, undergoing end milling with uncoated carbide inserts. The flank wear of the insert was observed and measured with the toolmaker's microscope. To examine machined surfaces, 3D surface topography was provided by the white light interferometer, and the arithmetical mean roughness (Ra) was calculated with the WYKO Vision32 software. The flank wear increases with cutting time, and the maximal flank wear is set as the flank wear criterion. As the cutting process progresses, tool wear is the predominant factor affecting the variation of surface roughness. According to the plots for the tool wear propagation and surface roughness variation, an optimal flank wear criterion can be defined which integrates the tool life and the surface roughness requirements for the finish milling process. 相似文献