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101.
含钡合金在钢液中的脱氧行为研究   总被引:7,自引:0,他引:7  
在MoSi2炉上采用MgO质坩蜗对钢管进行了含钡合金脱氧行为的研究。实验中钡系合金主要选取SiAUBa、SiCaBa、SiAlBaCa、SiAlBeCaSr及用于钙处理的SiCa包芯线,选用Al作为对比脱氧剂,考察了钡系合金脱氧的全氧含量,脱氧产物的分布、尺寸和形貌,探讨了钡系合金脱氧和对夹杂物变性作用的机理。  相似文献   
102.
The cellular neural network (CNN) architecture combines the best features from traditional fully-connected analog neural networks and digital cellular automata. The network can rapidly process continuous-valued (gray-scale) input signals (such as images) and perform many computation functions which traditionally were implemented in digital form. Here, we briefly introduce the the theory of CNN circuits, provide some examples of CNN applications to image processing, and discuss work toward a CNN implementation in custom CMOS VLSI. The role of analog computer-aided design (CAD) will be briefly presented as it relates to analog neural network implementation.This work is supported in part by the Office of Naval Research under Contract N00014-89-J1402, and the National Science Foundation under grant MIP-8912639.  相似文献   
103.
In this paper, a simple fuzzy-based algorithm to remove the impulse noise from images is proposed. To achieve real-time applications, the proposed filter architecture, which combines fuzzy noise detection and noise filtering, is also designed. With low computational complexity, simulation results show that the proposed filters effectively remove the impulse noise.  相似文献   
104.
This letter discusses the difference between piezoelectric constitutive relations for the case of one-dimensional stress and the case of one-dimensional strain, and its implications in the modeling of Rosen piezoelectric transformers.  相似文献   
105.
A practical model for a single-electron transistor (SET) was developed based on the physical phenomena in realistic Si SETs, and implemented into a conventional circuit simulator. In the proposed model, the SET current calculated by the analytic model is combined with the parasitic MOSFET characteristics, which have been observed in many recently reported SETs formed on Si nanostructures. The SPICE simulation results were compared with the measured characteristics of the Si SETs. In terms of the bias, temperature, and size dependence of the realistic SET characteristics, an extensive comparison leads to good agreement within a reasonable level of accuracy. This result is noticeable in that a single set of model parameters was used, while considering divergent physical phenomena such as the parasitic MOSFET, the Coulomb oscillation phase shift, and the tunneling resistance modulated by the gate bias. When compared to the measured data, the accuracy of the voltage transfer characteristics of a single-electron inverter obtained from the SPICE simulation was within 15%. This new SPICE model can be applied to estimating the realistic performance of a CMOS/SET hybrid circuit or various SET logic architectures.  相似文献   
106.
A type of CO2 sensor based on oxygen concentration cell was designed as following: Cell I: Pt | Au, O2,CO2|Na2CO3(Au)|NKBA(Au)|YSZ|O2, CO2|Pt or Cell Ⅱ: Pt|Au, O2, CO2|K2CO3(Au)|NKBA(Au)|YSZ|O2, CO2|Pt.(Na,K-β/β″-Al2O3 is named by NKBA). The sensor signal is consistent with the Nernstian slope within the region ofphase equilibrium for Na, K-β/β"-Al2O3 material. The relationship between CO2 sensor voltage response and phaseequilibrium of solid electrolyte Na, K-β/β-Al2O3 is discussed in this paper.  相似文献   
107.
用φ20mm离心萃取器两步法制取高纯钇   总被引:1,自引:0,他引:1  
本文研究了中钇富镧稀土的氧化物溶液在环烷酸中的萃取行为,测定了镧钇组成、温度变化与分离系数的关系;在P_(507)体系中研究了pH值与分配比的关系;提出用环烷酸、P_(507)两种萃取剂制备高纯钇的工艺流程。用84台φ20mm离心萃取器进行了一个月的台架试验,结果证明两种萃取剂有很好的互补性,在满足钇的纯度要求下有较高收率。离心萃取器具有易分相、体系存留量少、液流密闭性好等优点,它更适宜于粘度大、级数多、产品纯度要求高的体系。  相似文献   
108.
Mach网络服务器把本地IPC机制透明地扩充到网络环境,为分布式应用提供支持。本文介绍了Mach网络服务器的功能,内部组织结构及网络通讯的基本过程。  相似文献   
109.
CCD应用中的高速图象数据采集技术   总被引:6,自引:1,他引:5  
介绍了一种可用于精密光学测量的高速线阵CCD图象数据采集系统,给出了系统组成、各单元设计考虑和主要技术指标。  相似文献   
110.
We studied 722 reexcision scars of benign and malignant lesions (except melanocytic lesions) excised over a 24-month period. The formalin-fixed, paraffin-embedded tissue sections were examined histologically and immunohistochemically. The histological features of melanocytic hyperplasia were present in 59 cases (8%), 56 from the sun-exposed skin of the face and neck and three from the trunk [p < 0.00001]. The most common sites were the nose and lower eyelids, but the forehead was also frequently involved. Of the 59 patients, 41 were women (p < 0.0001). Basal cell carcinoma was the most frequent original lesion in both sexes (80%). No melanocytic hyperplasia was found in 663 cases (298 on the trunk and extremities and 365 on the head and neck). We have seen this reaction pattern following reexcision of melanocytic lesions as well. Thus, interpreting reexcision margins when lentigo maligna or similar lesions are reexcised may be fraught with difficulty. It is important for pathologists and dermatopathologists to recognize this phenomenon because histologically the presence of increased numbers of large melanocytes could be misinterpreted as melanoma in situ.  相似文献   
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