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1.
乳腺钼靶X线摄影是临床筛检早期乳腺癌的首选方法。通过对含有微钙化点钼靶X线图像的灰度分布特点进行分析,提出基于小波的反锐化掩模算法实现对钼靶X线图像的增强。实验结果表明,这种方法可以在抑制噪声的同时对图像进行有效增强,提高图像的对比度,特别是使钙化点的显示更为明显。  相似文献   

2.
超声红外热像技术是一种新型无损检测技术,对金属试件疲劳裂纹、复合材料冲击损伤等缺陷具有良好的检测效果。传统缺陷识别主要依靠肉眼识别和专业经验,对缺陷类型、缺陷程度的判断很难定量把握;基于时间序列的缺陷识别算法速度慢、精度差、自动化程度低。本文以超声红外热像技术中裂纹的检测为例,通过对比分析热图像分割区域中裂纹区域与亮点区域的形状、灰度等分布特征,提取了用于裂纹信息识别的特征参量,开发了基于加权支持向量机的裂纹自动识别算法,为实现超声红外热像技术中缺陷的自动识别奠定了基础。试验验证了本文所提特征参量和自动识别算法的有效性。  相似文献   

3.
医用红外热像仪在乳腺疾病普查中的应用研究   总被引:3,自引:0,他引:3  
对医用红外热像仪在医学上应用的物理基础、乳腺疾病普查中热图的拍摄方法、乳腺热图的分类、以及分析乳腺热图与临床诊断关系的一般原则方面进行了讨论  相似文献   

4.
医用红外热像技术由于其直观、无创及对疾病的早期诊断等优点而日益受到关注和应用。收集了近年来医用红外热像技术的相关研究文献,分别从疾病的早期探查、辅助诊断、临床疗效评定及中医针灸学研究等4方面分析医用红外热像技术的应用和研究近况,为临床疾病的早期诊断、疗效评价和应用研究提供参考依据,以促进医用红外热像技术的临床应用和发展。  相似文献   

5.
提出基于视觉显著性特征的乳腺钼靶X射线肿块检 测方法:首先从局 部显著性、全局 显著性和稀少性三方面计算显著图,利用显著图加权增强目标;然后根据前景目标数迭代确 定分割阈值对 加权后图像阈值分割;最后将分割后的前景区域视为疑似肿块区域,利用融合显著性特征及 基于中心-轮廓 距离的肿块形态特征识别肿块。本文利用MIAS数据库中多幅的乳腺X线图像进行实验验证, 结果表明, 本文提出的方法能够准确地分割肿块区域,肿块识别准确性较高。  相似文献   

6.
目的:探讨数字化乳腺钼靶三维立体定位技术对早期乳腺癌的诊断价值。方法:98例经定位穿刺、手术病理证实的早期乳腺癌患者,对其钼靶X线表现进行分析。结果:98例乳腺癌患者中结节肿块40例,成簇样钙化灶21例、细沙样钙化8例、短杆状钙化6例、局部腺体结构紊乱7例、局灶性致密影5例、导管增粗影4例、星芒征13例。结论:数字化三维立体定位技术是目前诊断早期乳腺癌并进行精准切除的首选而有效的方法。  相似文献   

7.
陈秋霞  向军  刘奇  刘剑 《激光杂志》2014,(3):65-66,69
提取乳腺肿瘤超声图像的肿瘤区域,计算乳腺肿瘤图像的纹理特征参数,研究纹理特征与肿瘤良恶性的关系。基于综合空间灰度共生矩阵计算11个乳腺肿瘤超声图像的纹理特征参数,然后分别利用模糊C均值和K-medoid聚类算法对乳腺肿瘤进行良恶性判别,同时,通过重复实验找到判别肿瘤良恶性的最佳特征参数组合。实验结果表明相关性、和方差、相关信息度量1和相关信息度量2四个特征参数组合的判别结果最好,达到了72.64%。因此,纹理特征在一定程度上能够反映良恶性乳腺肿瘤的区别,其对于鉴别乳腺肿瘤的良恶性是有效的。  相似文献   

8.
正常人体颜面温度分布及红外面像分析   总被引:10,自引:0,他引:10  
本文使用红外热象仪对116例健康人面部温度分布进行观察,并对面部热象图进行分析。观察结果有助于中医研究面像以及面部疾病的热像图诊断。  相似文献   

9.
乳腺X线摄影是临床筛检早期乳腺癌的首选方法.通过对乳腺X线图像的灰度分布特点进行分析,提出Top-hat滤波与多分辨小波相结合的算法实现对乳腺X线图像的增强.实验结果表明,这种方法可以在抑制噪声的同时对图像进行有效增强,提高图像的对比度,特别是使肿瘤区域的显示更为明显.  相似文献   

10.
红外热象仪诊断乳腺疾病的临床观察朱昭远,吴晓林(徐州医学院附属医院普外科、热象图室)我院自1991.2~1993.4采用HR-2热象仪对474例乳腺疾病进行诊断。经病理验证,获得满意的诊断符合率。检查时,室内温度18~20℃,相对湿度<50%,光线宜...  相似文献   

11.
From its emergence in the late 1980s as a lower cost alternative to early EEPROM technologies, flash memory has evolved to higher densities and speedsand rapidly growing acceptance in mobile applications.In the process, flash memory devices have placed increased test requirements on manufacturers. Today, as flash device test grows in importance in China, manufacturers face growing pressure for reduced cost-oftest, increased throughput and greater return on investment for test equipment. At the same time, the move to integrated flash packages for contactless smart card applications adds a significant further challenge to manufacturers seeking rapid, low-cost test.  相似文献   

12.
The parallel thinning algorithm with two subiterations is improved in this paper. By analyzing the notions of connected components and passes, a conclusion is drawn that the number of passes and the number of eight-connected components are equal. Then the expression of the number of eight-connected components is obtained which replaces the old one in the algorithm. And a reserving condition is proposed by experiments, which alleviates the excess deletion where a diagonal line and a beeline intersect. The experimental results demonstrate that the thinned curve is almost located in the middle of the original curve connectivelv with single pixel width and the processing speed is high.  相似文献   

13.
The relation between the power of the Brillouin signal and the strain is one of the bases of the distributed fiber sensors of temperature and strain. The coefficient of the Bfillouin gain can be changed by the temperature and the strain that will affect the power of the Brillouin scattering. The relation between the change of the Brillouin gain coefficient and the strain is thought to be linear by many researchers. However, it is not always linear based on the theoretical analysis and numerical simulation. Therefore, errors will be caused if the relation between the change of the Brillouin gain coefficient and the strain is regarded as to be linear approximately for measuring the temperature and the strain. For this reason, the influence of the parameters on the Brillouin gain coefficient is proposed through theoretical analysis and numerical simulation.  相似文献   

14.
Today, micro-system technology and the development of new MEMS (Micro-Electro-Mechanical Systems) are emerging rapidly. In order for this development to become a success in the long run, measurement systems have to ensure product quality. Most often, MEMS have to be tested by means of functionality or destructive tests. One reason for this is that there are no suitable systems or sensing probes available which can be used for the measurement of quasi inaccessible features like small holes or cavities. We present a measurement system that could be used for these kinds of measurements. The system combines a fiber optical, miniaturized sensing probe with low-coherence interferometry, so that absolute distance measurements with nanometer accuracy are possible.  相似文献   

15.
High purity organic-tantalum precursors for thin film ALD TaN were synthesized and characterized.Vapor pressure and thermal stability of these precursors were studied.From the vapor pressure analysis,it was found that TBTEMT has a higher vapor pressure than any other published liquid TaN precursor,including TBTDET,TAITMATA,and IPTDET.Thermal stability of the alkyl groups on the precursors was investigated using a 1H NMR technique.The results indicated that the tertbutylimino group is the most stable group on TBTDET and TBTEMT as compared to the dialkylamido groups.Thermal stability of TaN precursors decreased in the following order:TBTDET > PDMAT > TBTEMT.In conclusion,precursor vapor pressure and thermal stability were tuned by making slight variations in the ligand sphere around the metal center.  相似文献   

16.
In order to diagnose the laser-produced plasmas, a focusing curved crystal spectrometer has been developed for measuring the X-ray lines radiated from a laser-produced plasmas. The design is based on the fact that the ray emitted from a source located at one focus of an ellipse will converge on the other focus by the reflection of the elliptical surface. The focal length and the eccentricity of the ellipse are 1350 mm and 0.9586, respectively. The spectrometer can be used to measure the X- ray lines in the wavelength range of 0.2-0.37 nm, and a LiF crystal (200) (2d = 0.4027 nm) is used as dispersive element covering Bragg angle from 30° to 67.5°. The spectrometer was tested on Shengnang- Ⅱ which can deliver laser energy of 60-80 J/pulse and the laser wavelength is 0.35 μm. Photographs of spectra including the 1 s2p ^1P1-1s^2 ^1S0 resonance line(w), the 1s2p ^3P2-1s^2 1S0 magnetic quadrupole line(x), the 1s2p ^3P1-1 s^2 ^1S0 intercombination lines(y), the 1 s2p ^3S~1-1 s^2 ^1S0 forbidden line(z) in helium-like Ti Ⅹ Ⅺ and the 1 s2s2p ^2P3/2-1 s622s ^2S1/2 line(q) in lithium-like Ti Ⅹ Ⅹhave been recorded with a X-ray CCD camera. The experimental result shows that the wavelength resolution(λ/△ 2) is above 1000 and the elliptical crystal spectrometer is suitable for X-ray spectroscopy.  相似文献   

17.
This paper reviews our recent development of the use of the large-scale pseudopotential method to calculate the electronic structure of semiconductor nanocrystals, such as quantum dots and wires, which often contain tens of thousands of atoms. The calculated size-dependent exciton energies and absorption spectra of quantum dots and wires are in good agreement with experiments. We show that the electronic structure of a nanocrystal can be tuned not only by its size,but also by its shape. Finally,we show that defect properties in quantum dots can be significantly different from those in bulk semiconductors.  相似文献   

18.
An improving utilization and efficiency of critical equipments in semiconductor wafer fabrication facilities are concerned. Semiconductor manufacturing FAB is one of the most complicated and cost sensitive environments. A good dispatching tool will make big difference in equipment utilization and FAB output as a whole. The equipment in this paper is In-Line DUV Scanner. There are many factors impacting utilization and output on this equipment group. In HMP environment one of the issues is changing of reticule in this area and idle counts due to load unbalance between equipments. Here we'll introduce a rule-based RTD system which aiming at decreasing the number of recipe change and idle counts among a group of scanner equipment in a high-mixed-products FAB.  相似文献   

19.
The epi material growth of GaAsSb based DHBTs with InAlAs emitters are investigated using a 4 × 100mm multi-wafer production Riber 49 MBE reactor fully equipped with real-time in-situ sensors including an absorption band edge spectroscope and an optical-based flux monitor. The state-of-the-art hole mobilities are obtained from 100nm thick carbon-doped GaAsSb. A Sb composition variation of less than ± 0.1 atomic percent across a 4 × 100mm platen configuration has been achieved. The large area InAlAs/GaAsSb/InP DHBT device demonstrates excellent DC characteristics,such as BVCEO>6V and a DC current gain of 45 at 1kA/cm2 for an emitter size of 50μm × 50μm. The devices have a 40nm thick GaAsSb base with p-doping of 4. 5 × 1019cm-3 . Devices with an emitter size of 4μm × 30μm have a current gain variation less than 2% across the fully processed 100mm wafer. ft and fmax are over 50GHz,with a power efficiency of 50% ,which are comparable to standard power GaAs HBT results. These results demonstrate the potential application of GaAsSb/InP DHBT for power amplifiers and the feasibility of multi-wafer MBE for mass production of GaAsSb-based HBTs.  相似文献   

20.
A new quantum protocol to teleport an arbitrary unknown N-qubit entangled state from a sender to a fixed receiver under M controllers(M < N) is proposed. The quantum resources required are M non-maximally entangled Greenberger-Home-Zeilinger (GHZ) state and N-M non-maximally entangled Einstein-Podolsky-Rosen (EPR) pairs. The sender performs N generalized Bell-state measurements on the 2N particles. Controllers take M single-particle measurement along x-axis, and the receiver needs to introduce one auxiliary two-level particle to extract quantum information probabilistically with the fidelity unit if controllers cooperate with it.  相似文献   

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