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Brain MR Image Segmentation and Bias Field Estimation Using Coherent Local and Non-local Spatial Constraints

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Brain MR Image Segmentation and Bias Field Estimation Using ...

Numerical analysis of carbon saving potential in a top gas recycling oxygen blast furnace

第25届中国控制与决策会议

作者： Zhang Shi she.Lihuang Wang Hongyan Zhong Hua Academy of Information Science and Engineering Northeastern University

ISBN: (纸本)9781467355339

Clinical brain MR images usually contain noise and bias field （bf）, which make the brain tissue segmentations difficult. Most of the current segmentation methods only focus on one unfavorable factor. The Coherent local intensity clustering algorithm （CLIC） algorithm proposed recently is good at dealing with the bf problem in images, but it has a poor anti-noise ability, for it doesn’t consider non-local spatial constraint. In this paper, taking care of all these unfavorable factors simultaneously, we introduce the non-local spatial constraint into CLIC algorithm for brain MR image segmentations. Therefore, the proposed algorithm drives by both the coherent local and non-local spatial constraints. The coherent local information ensures the smoothness of the bias field estimation and the non-local spatial information reduces the noise effect during the segmentation. The proposed method has been successfully applied to brain MR images, and experiment results show that this method has stronger anti-noise property, smoother bias field estimation and higher segmentation precision than other reported fuzzy clustering algorithms.

关键词： Bias field fuzzy clustering MR image segmentation non-local constraint coherent local constraint

来源： cnki会议评论

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Journal of Iron and Steel Research International 2017年第6期24卷 608-616页

作者： Xue-feng she.Xiu-wei An Jing-song Wang Qing-guo Xue Ling-tan Kong State Key Laboratory of Advanced Metallurgy University of Science and Technology Beijing Beijing 100083 China Qingdao Special Steel Company Limited Shandong Qingdao 266409 Shandong China

Aiming at the current characteristics of blast furnace （bf） process, carbon saving potential of blast furnace was investigated from the perspective of the relationship between degree of direct reduction and carbon consumption. A new relationship chart between carbon consumption and degree of direct reduction, which can reflect more real situation of blast furnace operation, was establishe.. Further- more, the carbon saving potential of hydrogen-rich oxygen blast furnace （Obf） process was ana- lyzed. Then, the policy implications based on this relationship chart establishe. were suggested. On this basis, the method of improving the carbon saving potential of blast furnace was recycling the top gas with removal of CO2 and H2O or increasing hydrogen in bf gas and full oxygen blast. The results show that the carbon saving potential in traditional blast furnace （Tbf） is only 38 56 kg · t ^-1 while that in Obf is 138 kg · t ^-1. Theoretically, the lowest carbon consumpt!on of Obf is 261 kg · t ^-1 and the corresponding degree of direct reduction is 0.04. In addition, the theoretical lowest carbon consumption of hydrogen-rich Obf is 257 kg · t ^-1. The modeling analysis can be used to estimate the carbon savings potential in new ironmaking process and its related CO2 emissions.

关键词： Blast furnace processDirect reduction degreeCarbon consumptionDirect reductionCarbon saving potentiaOxygen blast furnace

A Modified Model for Calculating Theoretical Flame Temperature in Blast Furnace and Its Application

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Journal of Iron and Steel Research International 2015年第1期22卷 9-14页

作者： Li ZHU Keng WU Er-hua ZHANG Yuan she.Wen-long ZHAN Qi-hang LIU State Key Laboratory of Advanced Metallurgy University of Science and Technology Beijing

The theoretical flame temperature （TFT） before tuyere, always highly concerned by blast furnace （bf） operators, is one of the most important parameters for evaluating the thermal state of hearth. However, some influ- encing parameters, for example, the SiO2 reduction by carbon, were always neglected or inaccurate when calculating the TFT. According to the definition of TFT, the temperature of coke into raceway and the reduction rate of SiO2 in ash of coke and pulverized coal were obtained by analyzing the samples before tuyere in blast furnace. Taking full ac- count of different factors, a modified model for calculating the TFT in blast furnace was establishe.. The effects of the oxygen enrichment rate, the reduction rate of SiO2 in raceway, the ash content in coke and pulverized coal and the pulverized coal injection （PCI） rate on TFT were determined quantitatively. The modified model was applied to selecting the used coal for PCI in blast furnace. Considering the different SiO2 contents of mixed coal, the calculated TFT remained a stable level. This showed that the selected coal could be suitable for PCI in blast furnace.

关键词： theoretical flame temperature blast furnace SiO2 reduction rate modified model

Basic properties of steel plant dust and technological properties of direct reduction

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International Journal of Minerals,Metallurgy and Materials 2011年第3期18卷 277-284页

作者： Xue-feng she.Jing-song Wang Qing-guo Xue Yin-gui Ding she.g-she.g Zhang Jie-ji Dong Hui Zeng School of Metallurgical and Ecological Engineering University of Science and Technology Beijing Beijing 100083 China Shandong Laiwu Iron and Steel Co. Ltd. Laiwu 271104 China

Basic physicochemical properties of the dust from Laiwu Iron and Steel Co. Ltd. were studied. It is found that C, Zn, K, Na, etc. exist in the fabric filter dust, off gas （OG） sludge, fine ash in converter, and electrical field dust in sinter. Among these, OG sludge gives the finest particle, more than 90% of which is less than 2.51 mm. The dust can lead to a serious negative influence on the production of sintering and blast furnaces （bf） if it is recycled in sintering. The briquette and reduction experimental results showed that the qualified strength could be obtained in the case of 8wt% molasses or 4wt% QT-10 added as binders. Also, more than 75% of metallization ratio, more than 95% of dezincing ratio, as well as more than 80% of K and Na removal rates were achieved for the briquettes kept at 1250℃ for 15 min during the direct reduction process. SEM observation indicated that the rates of indirect reduction and carbonization became dominating when the bri-quettes were kept at 1250℃ for 6 min.

关键词： steel metallurgy dust zinc direct reduction process briquettes

Softening and Melting Behavior of Ferrous Burden under Simulated Oxygen Blast Furnace Condition

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Journal of Iron and Steel Research International 2015年第4期22卷 297-303页

作者： Hua-jie ZHANG Xue-feng she.Yi-hua HAN Jing-song WANG Fan-bo ZENG Qing-guo XUE State Key Laboratory of Advanced Metallurgy University of Science and Technology Beijing

The softening and melting behavior of sinter, pellet and mixed burden was researched through high tem- perature reaction tests under load simulating traditional blast furnace （T-bf） and oxygen blast furnace （Obf） condi- tions. The results indicated that compared with T-bf, the softening zone of sinter and pellet became wide, but the melting zone became narrow in Obf. The permeabilities of both sinter and pellet were improved in Obf. Under the condition of Obf, the temperature of softening zone of mixed burden was increased by 63 K, but the temperature of melting zone was decreased by 76 K. Therefore, the permeability of material layer was significantly improved. This was mainly caused by the change of the melting behavior of pellet. In addition, the quality Of dripping iron in Obf was much better than that of T-bf.

关键词： oxygen blast furnace softening zone melting zone ferrous burden

添加剂对镁合金表面Ce-Mn转化膜组织和耐蚀性能的影响

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轻合金加工技术 2016年第2期44卷 54-59页

作者：武卫社广东华昌铝厂有限公司广东佛山528231

以Ce(NO3)3-KMn O4为主要成膜剂,向体系中分别加入NH4HF2、Na F、Sr Cl2、Na bf4、十二烷基苯磺酸钠(C18H29-Na O3S)、Na B4O7添加剂,室温下在镁合金表面制备了Ce-Mn转化膜。用扫描电镜(SEM)及能谱仪(EDS)对转化膜的微观形貌和成分进行... 详细信息

以Ce(NO3)3-KMn O4为主要成膜剂,向体系中分别加入NH4HF2、Na F、Sr Cl2、Na bf4、十二烷基苯磺酸钠(C18H29-Na O3S)、Na B4O7添加剂,室温下在镁合金表面制备了Ce-Mn转化膜。用扫描电镜(SEM)及能谱仪(EDS)对转化膜的微观形貌和成分进行分析,并用极化曲线研究转化膜的耐腐蚀性能。结果表明,添加剂不改变膜层成分,但对膜层组织结构及耐腐蚀性能有较大影响,较佳的添加剂为十二烷基苯磺酸钠,添加十二烷基苯磺酸钠生成的转化膜,膜层裂纹细小,耐蚀性更好。

关键词：镁合金 Ce-Mn转化膜添加剂耐蚀性

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离子液体中微波合成CdS,ZnS纳米晶粒

化学研究与应用 2011年第6期23卷 796-800页

作者：曾伟佘金华梁凡蒋亚西南交通大学生命科学与工程学院化学化工系四川成都610031 中国民航总局第二研究所四川成都610041 西南交通大学地球科学与环境工程学院环境工程系四川成都610031

纳米尺度的金属硫化物晶粒MS（M=Cd,Zn）在一般合成条件下生长以及晶化过程都比较缓慢。而在高极性的离子液体中用微波加热的方式,100℃、10 min就可以合成出2~5 nm的硫化锌、5~8 nm的硫化镉,晶化程度高,并与粉末衍射数据的计算结果相... 详细信息

纳米尺度的金属硫化物晶粒MS（M=Cd,Zn）在一般合成条件下生长以及晶化过程都比较缓慢。而在高极性的离子液体中用微波加热的方式,100℃、10 min就可以合成出2~5 nm的硫化锌、5~8 nm的硫化镉,晶化程度高,并与粉末衍射数据的计算结果相吻合。通过X射线粉末衍射图可清楚对比不同加热条件下产物的结晶程度;紫外-可见吸收光谱显示微波加热4~5 min,合成产物的尺寸已经达到稳定;透射电镜以及电子衍射照片显示微波合成产物为纳米晶粒。

关键词：金属硫化物纳米晶粒微波加热离子液体

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高炉铜冷却壁设计优化之管见

炼铁 2020年第3期39卷 7-12页

作者：沈大伟陈名炯佘京鹏广东省汕头市汕头华兴冶金设备股份有限公司技术部 515000 汕头华兴冶金设备股份有限公司

针对铜冷却壁的损坏特征,就铜拎却壁的设计优化进行了探讨。铜冷却壁破损主要是热面磨损并且具有明显的区域性(绝大部分是炉腹和炉腰交界位置),除了应从高炉设计、安装、操作维护等进行相应优化外,关键应该同步对铜冷却壁设计结构进行优... 详细信息

针对铜冷却壁的损坏特征,就铜拎却壁的设计优化进行了探讨。铜冷却壁破损主要是热面磨损并且具有明显的区域性(绝大部分是炉腹和炉腰交界位置),除了应从高炉设计、安装、操作维护等进行相应优化外,关键应该同步对铜冷却壁设计结构进行优化,如采用铜冷却壁热面镶嵌钢砖设计,既能提高铜冷却壁的耐磨性和挂渣能力,又能分割和支撑渣皮,以降低渣皮脱落对炉况影响。

关键词：高炉铜冷却壁镶嵌钢砖耐磨性挂渣能力

EXPERIMENTAL STUDY ON THE COPPER COOLING STAVE WITH DIFFERENT WATER COOLING CHANNELS

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EXPERIMENTAL STUDY ON THE COPPER COOLING STAVE WITH DIFFEREN...