基于MAS的数据挖掘在输电故障诊断中的应用

数据挖掘就是从大量的数据中发现知识的技术。在相关领域专家指导下,数据挖掘技术可以实现对海量数据的智能分析,得到事物本质及可预测其发展趋势的、隐含的模式或规律。研究了基于多Agent的输电故障诊断系统,该系统采用数据挖掘的多种分析方法,与数据仓库、联机分析处理和多Agent等技术相结合,建立了能够监控输电网数据的综合智能决策支持系统,推进了电力企业现代化的发展。     

Application of a Waste Carbon Material as the Carbonaceous Reductant During Silicon Production

It is important to study the application of alternative carbon reductants for industrial silicon smelting to reduce consumption of carbonaceous reducing agents, electricity, and CO₂ emissions during silicon production. In this study, an industrial experiment was carried out in an 8 MVA submerged arc furnace using waste carbon material in place of approximately 20% partial reducing agents. The system was analyzed for silicon yield, power consumption, overall energy efficiency, CO₂ emissions, and the utilization rate of carbonaceous materials. The system improved the efficiency of carbonaceous materials and decreased power consumption using alternative carbon reductants. The results have showed that use of waste carbon materials reduced carbon emissions per ton silicon by more than 19.14% and specific CO₂ emissions decreased to 0.865 t.     

STUDY ON THE ON－LINE OPTIMAL CONTROL OF PARAMETERS OF THREE－CONE BLAST HOLE DRILLS

ＳＴＵＤＹＯＮＴＨＥＯＮ－ＬＩＮＥＯＰＴＩＭＡＬＣＯＮＴＲＯＬＯＦＰＡＲＡＭＥＴＥＲＳＯＦＴＨＲＥＥ－ＣＯＮＥＢＬＡＳＴＨＯＬＥＤＲＩＬＬＳＳＴＵＤＹＯＮＴＨＥＯＮ－ＬＩＮＥＯＰＴＩＭＡＬＣＯＮＴＲＯＬＯＦＰＡＲＡＭＥＴＥＲＳＯＦＴＨＲＥＥ－ＣＯＮＥ...     

Impurities Removal From Metallurgical Grade Silicon Using Gas Blowing Refining Techniques

The removal of impurities from metallurgical grade silicon using the O₂ and H₂O-O₂ gas blowing techniques was firstly studied by thermodynamics. The relationships between the boron content in refined silicon and the equilibrium partial pressures of gaseous boride species were established, which shows a theoretical limitation for boron removal from metallurgical grade silicon using the H₂O-O₂ gas blowing technique. The data also showed that the impurity boron in silicon was mainly volatilized in the form of B₃H₃O₆, BHO₂ and BO and the volatilization of boric hydrate species was much more than that of the oxide species. The impurities removal from metallurgical grade silicon including Fe, Al, Ca, Ti, B, P and C was studied using an O₂ gas blowing in a ladle and in succession a mixed Ar-H₂O-O₂ gas blowing was operated in a DC arc furnace for boron removal. It showed a removal efficiency higher than 90 % for Al, Ca and 50 % for B using the O₂ gas blowing technique in the ladle. Impurity boron was reduced from 35 ppmw to 18 ppmw in the ladle and it was once again reduced to 0.6 ppmw using an Ar-H₂O-O₂ gas blowing technique in the DC arc furnace for a systematic pressure of 5 Pa when the ratio of H₂O to O₂ and the refining times are 2:1 and 12 min, respectively.     

加快太阳级硅制备新技术研发 促进硅资源可持续发展

随着光伏产业的迅速发展,太阳级硅原料供给不足已经成为光伏产业发展的最主要的瓶颈之一。为了满足太阳能电池工业健康发展,研发一个不依赖于半导体硅生产的低成本太阳能级硅供应体系是非常必要的。云南省硅资源及冶金级硅产品品质优良,水电资源也非常丰富,加快对太阳级硅制备新技术的研究开发不仅具有广阔的市场潜力,而且对促进云南省硅资源的可持续发展,提高云南的高新技术水平,加速半导体材料的发展都具有重要的意义和作用。     

定向凝固技术去除超冶金级硅中铁的实验研究

研究了不同下拉速率对超冶金级硅中铁杂质的去除效果.结果表明,在较低的下拉速率下,对铁的去除效果最好,底部去除率高达99.45％.其原因主要在于杂质铁在凝固过程中的分凝效应及不同凝固速率.     

Study on volatilization rate of silicon in multicrystalline silicon preparation from metallurgical grade silicon

The quantity of silicon lost during evaporation is greater than theoretical expectation during the purification of metallurgical grade silicon by vacuum evaporation. In this paper, silicon volatilization rates were measured for evaporation times of 30, 45 and 60 min at 1723, 1773 and 1823 K, respectively. Results indicate that volatilization rates determined in our experiments are one or two orders of magnitude greater than those from theoretical calculation. The equation for theoretical calculation was revised (ω = (2.23-6.30)× 10⁻¹ p_pa(M/T)^1/2) using silicon evaporation coefficient of 8.5-24. The details of the experimental set-up were found to be important and the mass of silicon evaporated in particular was found to be related to the water-cooling system. The carbon/graphite inserts also and the presence of trace amounts of oxygen in the vacuum furnace could reduce the content of silicon in gaseous phase and support the evaporation of silicon. It was found under certain conditions that there are two principal stages involved: 1) Formation of vapor-liquid equilibrium, 2) Maintenance of the established vapor-liquid equilibrium during the silicon evaporation process. It was found that silicon process losses can be reduced by shortening the time of the first stage.     

基于SURF特征的航空序列图像位置估计算法

视觉传感器在航空无人机导航和定位任务中应用越来越广泛。针对无人机位置参数估计问题,提出了一种基于SURF特征的图像配准算法,该算法能够适应航空序列图像的旋转、尺度变换及噪声干扰,实现无人机位置的精确估计。构建了SURF尺度空间,运用快速Hessian矩阵定位极值点,计算出航空图像的64维SURF特征描述子;基于Hessian矩阵迹完成特征点匹配;使用RANSAC算法剔除出格点,实现位置参数的精确估计。通过航空图像序列实测数据位置估计实验,验证了该算法的有效性。     

Solving quantified constraint satisfaction problems with value selection rules

Solving a quantified constraint satisfaction problem (QCSP) is usually a hard task due to its computational complexity. Exact algorithms play an important role in solving this problem, among which backtrack algorithms are effective. In a backtrack algorithm, an important step is assigning a variable by a chosen value when exploiting a branch, and thus a good value selection rule may speed up greatly. In this paper, we propose two value selection rules for existentially and universally quantified variables, respectively, to avoid unnecessary searching. The rule for universally quantified variables is prior to trying failure values in previous branches, and the rule for existentially quantified variables selects the promising values first. Two rules are integrated into the state-of-the-art QCSP solver, i.e., QCSPSolve, which is an exact solver based on backtracking. We perform a number of experiments to evaluate improvements brought by our rules. From computational results, we can conclude that the new value selection rules speed up the solver by 5 times on average and 30 times at most. We also show both rules perform well particularly on instances with existentially and universally quantified variables occurring alternatively.     

生物质和石油焦混合反应动力学特征

采用德国NETZSCH公司制造的STA449F3型超高温同步热分析仪器,对生物质和石油焦的催化协同气化特性进行了研究。研究结果表明,生物质对较稳定的石油焦的反应性能具有催化作用,随着生物质配比增加最大反应速率向低温方向移动,并通过理论计算和实验值对比发现生物质和石油焦混合并非简单反应的叠加,而是发生了协同反应。