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基于终端代价函数的连续搅拌反应釜无穷时域经济性预测控制优化

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计算机应用与软件 2024年第9期41卷 48-53,76页

作者：毛冉郑鹏远杨亦玘王雅琳秦海杰上海电力大学自动化工程学院上海200090

针对连续搅拌反应釜,设计一种基于不变集技术和终端代价函数的无穷时域经济性预测控制优化算法。在经济指标中引入动态指标,构造基于寻优动态指标加权矩阵系数的二次复合性能指标,进而通过不变集技术离线计算终端约束集和终端代价函数;... 详细信息

针对连续搅拌反应釜,设计一种基于不变集技术和终端代价函数的无穷时域经济性预测控制优化算法。在经济指标中引入动态指标,构造基于寻优动态指标加权矩阵系数的二次复合性能指标,进而通过不变集技术离线计算终端约束集和终端代价函数;将有限时域内的复合性能指标附加终端代价函数,构造无穷时域性能指标,对连续搅拌反应釜进行无穷时域优化控制,改善经济性能;仿真验证了所设计算法的有效性。

关键词：连续搅拌反应釜寻优动态指标加权矩阵系数二次复合性能指标终端代价函数无穷时域经济性预测控制

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考虑电感饱和的逆变器变开关频率控制仿真

计算机仿真 2024年第4期41卷 65-68,474页

作者：杭阿芳王秀梅金陵科技学院机电工程学院江苏南京211169 南京邮电大学电子与光学工程学院江苏南京211169

不当操作会导致电感饱和状态下逆变器功率损耗严重,为了提升频率控制的稳定性,提出考虑电感饱和的逆变器变开关频率控制方法。根据逆变器的构成获取相关参数的矢量关系,利用基尔霍夫电压定律生成电感饱和状态的逆变器数学模型,通过旋转... 详细信息

不当操作会导致电感饱和状态下逆变器功率损耗严重,为了提升频率控制的稳定性,提出考虑电感饱和的逆变器变开关频率控制方法。根据逆变器的构成获取相关参数的矢量关系,利用基尔霍夫电压定律生成电感饱和状态的逆变器数学模型,通过旋转构建逆变器在dp坐标系下的数学模型,用于预测推导逆变器的电压值。设计开关控制的三大核心成分,分别为功率鉴定器、频率鉴定器和频率滞环比较器,利用电压定向矢量控制方法分别从三个核心成分中得出逆变器的损耗、功率控制结果以及频率状态量误差,完成逆变器变开关频率控制。实验结果表明,所提方法的电压控制效果较好,频率控制稳定性较高。

关键词：电感饱和逆变器开关频率控制频率环基尔霍夫电压定律

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河南省主要河川径流变化归因

南水北调与水利科技（中英文） 2024年第2期22卷 228-236页

作者：竹磊磊王纪军吴璐杨婷苏晓乐李芳中国气象局河南省农业气象保障与应用技术重点开放实验室郑州450003 河南省气候中心郑州450003

为相对全面客观地分析气候变化和人类活动对河南省主要河川径流变化的影响,基于河南省内卫河、伊洛河、洪汝河和唐河流域1961—2022年径流和降水资料,以及国家气候中心根据Penman-Monteith公式计算的年潜在蒸散发资料,比较4个蒸发对比... 详细信息

为相对全面客观地分析气候变化和人类活动对河南省主要河川径流变化的影响,基于河南省内卫河、伊洛河、洪汝河和唐河流域1961—2022年径流和降水资料,以及国家气候中心根据Penman-Monteith公式计算的年潜在蒸散发资料,比较4个蒸发对比站年潜在蒸散发和蒸发皿年蒸发值,运用Mann-Kendall突变检验法和累积双曲线法分析4个研究流域控制水文站年径流序列的变化趋势和突变年份,以及4个流域年降水和潜在蒸散发的变化趋势。采用基于Budyko假设的弹性系数法对径流变化开展归因分析。结果表明:4个蒸发对比站年潜在蒸散发与蒸发皿年蒸发变化趋势基本一致,4个水文站年径流深及4个流域年降水和年潜在蒸散发均呈下降趋势。4个水文站年径流深分别在1977年、1985年、2008年和2010年发生了突变。气候变化对径流减少的贡献率在卫河和伊洛河流域为7%以下,在洪汝河和唐河流域约为12%~18%,降水减少不显著和潜在蒸散发呈下降趋势是贡献率小的原因,可见人类活动是影响4个流域径流变化的主要驱动因素。

关键词：弹性系数法气候变化人类活动径流变化卫河伊洛河洪汝河唐河

西秦岭地区猪婆沟金矿成矿物质来源及矿床成因分析

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西北地质 2024年第1期57卷 219-229页

作者：焦阳冯俊环甘肃省地质矿产勘查开发局第一地质矿产勘查院甘肃天水741020

猪婆沟金矿位于西秦岭之北秦岭鸳鸯镇-关子镇蛇绿混杂岩带的反“S”形构造的转折端,金矿体赋存在早古生代李子园群中,矿体的产出受NW向和NE向韧性断裂及其次级构造控制,矿体形态为脉状。矿床热液期主成矿阶段石英中包裹体主要为气液两... 详细信息

猪婆沟金矿位于西秦岭之北秦岭鸳鸯镇-关子镇蛇绿混杂岩带的反“S”形构造的转折端,金矿体赋存在早古生代李子园群中,矿体的产出受NW向和NE向韧性断裂及其次级构造控制,矿体形态为脉状。矿床热液期主成矿阶段石英中包裹体主要为气液两相包裹体、含子晶三相包裹体。含子晶三相包裹体的冰点温度为-4.8~-4.3℃;气液两相包裹体的冰点温度为-5.3~-0.1℃。该阶段含子晶三相包裹体的均一温度为141.3~198.6℃,平均为160.7℃;气液两相包裹体的均一温度为128.9~285.3℃,平均为174.1℃。成矿流体的均一温度值为130~170℃,峰值范围较宽。流体盐度为1.40~8.28%NaCleqv,平均为5.84%NaCleqv,具有中低温、低盐度特征;石英δ18OH2O值为-3.29‰~4.42‰,δD值为-110.1‰~-86.6‰,成矿流体来源于原生岩浆水,在岩浆分异成矿的过程中,大气降水的含量逐渐增多。主成矿阶段黄铁矿和毒砂δ34S值为10.7‰~11.5‰,矿物质分别来源于岩浆岩和地层;Pb同位素组成相似,主要来源于造山带铅,有部分上地壳铅和地幔铅加入,成矿物质来源于岩浆岩和地层两个端元,具有多期次特征。综合分析认为,猪婆沟金矿成因类型属沉积变质-岩浆期后热液叠加改造的构造蚀变岩型金矿床。

关键词：流体包裹体成矿流体成矿物质同位素地球化学猪婆沟金矿西秦岭地区

Orthogonal transformation operation theorem of a spatial universal uniform rotating magnetic field and its application in capsule endoscopy

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Science China(Technological Sciences) 2017年第6期60卷 854-864页

作者： ZHANG YongShun YU ZiChun YANG HuiYuan HUANG YunKui CHEN Jun Key Laboratory for Precision & Non-traditional Machining of Ministry of Education of China Dalian University of Technology The State Key Laboratory of Mechanical Transmissions Chongqing University Department of Mechanical Engineering School of Naval Architecture and Ocean Engineering Harbin Institute of Technology

According to the anti-phase sine current superposition theorem, the orientation, the magnetic flux density, the angular speed and the rotational direction of the spatial universal rotating magnetic field (SURMF) can be controlled within the tri-axial orthogonal square Helmholtz coils (TOSHC). Nevertheless, three coupling direction angles of the normal vector of the SURMF in the Descartes coordinate system cannot be separately controlled, thus the adjustment of the orientation of the SURMF is difficult and the flexibility of the robotic posture control is restricted. For the dimension reduction and the decoupling of control variables, the orthogonal transformation operation theorem of the SURMF is proposed based on two independent rotation angular variables, which employs azimuth and altitude angles as two variables of the three-phase sine current superposition formula derived by the orthogonal rotation inverse transformation. Then the unique control rules of the orientation and the rotational direction of the SURMF are generalized in each spatial quadrant, thus the scanning of the normal vector of the SURMF along the horizontal or vertical direction can be achieved through changing only one variable, which simplifies the control process of the orientation of the SURMF greatly. To validate its feasibility and maneuverability, experiments were conducted in the animal intestine utilizing the innovative dual hemisphere capsule robot (DHCR) with active and passive modes. It was demonstrated that the posture adjustment and the steering rolling locomotion of the DHCR can be realized through single variable control, thus the orthogonal transformation operation theorem makes the control of the orientation of the SURMF convenient and flexible significantly. This breakthrough will lay a foundation for the human-machine interaction control of the SURMF.

关键词： dual hemisphere capsule robot (DHCR) spatial universal rotating magnetic field (SURMF) orthogonal transformation operation variable decoupling

Assessing the uncertainties of phytoplankton absorption-based model estimates of marine net primary productivity

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Acta Oceanologica Sinica 2017年第6期36卷 112-121页

作者： TAO Zui MA Sheng YANG Xiaofeng WANG Yan State Key Laboratory of Remote Sensing Science Institute of Remote Sensing and Digital EarthChinese Academy of SciencesBeijing 100101China Beijing North-Star Digital Remote Sensing Technology Co.Ltd. Beijing 100120China State Environmental Protection Key Laboratory of Numerical Modeling for Environment Impact Assessment Beijing 100012China

Satellite-derived phytoplankton pigment absorption （aph） has been used as a key predictor of phytoplankton photosynthetic efficiency to estimate global ocean net primary production （NPP）. In this study, an aph-based NPP model （AbPM） with four input parameters including the photosynthetically available radiation （PAR）, diffuse attenuation at 490 nm （Ka（490））, euphotic zone depth （Zeu） and the phytoplankton pigment absorption coefficient （aph） is compared with the chlorophyll-based model and carbon-based model. It is found that the AbPM has significant advantages on the ocean NPP estimation compared with the chlorophyll-based model and carbon- based model. For example, AbPM greatly outperformed the other two models at most monitoring sites and had the best accuracy, including the smallest values of RMSD and bias for the NPP estimate, and the best correlation between the observations and the modeled NPPs. In order to ensure the robustness of the model, the uncertainty in NPP estimates of the AbPM was assessed using a Monte Carlo simulation. At first, the frequency histograms of simple difference （fi）, and logarithmic difference （~LOG） between model estimates and in situ data confirm that the two input parameters （Zeu and PAR） approximate the Normal Distribution, and another two input parameters （aph and Ka（490）） approximate the logarithmic Normal Distribution. Second, the uncertainty in NPP estimates in the AbPM was assessed by using the Monte Carlo simulation. Here both the PB （percentage bias）, defined as the ratio of ANPP to the retrieved NPP, and the CV （coefficient of variation）, defined as the ratio of the standard deviation to the mean are used to indicate the uncertainty in the NPP brought by input parameter to AbPM model. The uncertainty related to magnitude is denoted by PB and the uncertainty related to scatter range is denoted by CV. Our investigations demonstrate that PB of NPP uncertainty brought by all parameters with an annual mean of 5.5% covered a ran

关键词： marine net primary production phytoplankton pigment absorption satellite remote sensing uncertainty analysis Monte Carlo simulation

CNT@Ni-MOFs的制备及其在超级电容器中的应用

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武汉工程大学学报 2024年第3期46卷 258-266页

作者：何清牟雨航孟辰尧张宇刘辉李亮武汉工程大学材料科学与工程学院湖北武汉430205

金属有机骨架(MOFs)材料因其具有较高的比表面积和结构功能多样性而在超级电容器中具有广阔的应用前景。通过溶剂热法制备电化学性能优异的碳纳米管@镍基金属有机骨架(CNT@Ni-MOFs)复合材料。使用X射线衍射、扫描电子显微镜及X射线光电... 详细信息

金属有机骨架(MOFs)材料因其具有较高的比表面积和结构功能多样性而在超级电容器中具有广阔的应用前景。通过溶剂热法制备电化学性能优异的碳纳米管@镍基金属有机骨架(CNT@Ni-MOFs)复合材料。使用X射线衍射、扫描电子显微镜及X射线光电子能谱对其成分和结构进行表征,研究结果表明:CNT@Ni-MOFs结构是由柔性CNT连接着棒状结构的Ni-MOFs形成的导电网络结构,其棒状结构的Ni-MOFs直径约0.5μm,长度为4~5μm。研究了反应时间对CNT@Ni-MOFs结构和电化学性能的影响,结果表明:当反应时间为12 h时,Ni-MOFs生长完整且均匀,Ni-MOFs颗粒数量适中且均匀负载于CNT上,同时还减少了团聚发生。CNT@Ni-MOFs复合电极具有比单独Ni-MOFs更好的比电容性能,其中CNT@Ni-MOFs12在电流密度1 A/g下的比电容达到719.8 F/g,而Ni-MOFs的比电容仅为87.1 F/g,且CNT的比电容也仅仅为43.5 F/g。此外,扫描速率为200 mV/s下,CNT@Ni-MOFs12电极材料经1 000次的线性伏安循环测试后其比电容保持率为96.8%。

关键词：超级电容器碳纳米管金属有机骨架复合材料电极

Effect of processing on the antioxidant activities of porridges and Pittu prepared from finger millets (Eleusine coracana)

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Food Production, Processing and Nutrition 2022年第1期4卷 235-248页

作者： Anoma Chandrasekara Indraneela Senanayake Disna Kumari Fereidoon Shahidi Department of Applied Nutrition Wayamba University of Sri LankaMakanduraColombo 60170GonawilaSri Lanka Department of Biochemistry Memorial University of NewfoundlandSt.John’sNL A1B 3X9Canada

Finger millets are important coarse grains that exhibit high levels of phenolic compounds and antioxidant activities among other cereals. Grains are subjected to a number of thermal treatments and this could affect the contents and bioactivities of phenolic compounds. The aim of the present study was to determine the phenolic contents and antioxidant activities of finger millet flour and foods, namely porridges and Pittu subjected to several thermal treatments such as roasting, parboiling, and parboiled roasting of flour and open boiling and steaming of foods prepared using flour. The effect of the addition of spices on phenolic content and antioxidant activities to open boiled foods was determined. Antioxidant activities of phenolic extracts obtained from finger millet flour and foods were studied for their total phenolic, flavonoids and proanthocyanidins contents, radical scavenging capacities, reducing power, ferrous ion chelating capacity, and antioxidant activity in a β-carotene/linoleate emulsion. The roasted flour and foods had higher total phenolic content (TPC) than other counterparts and ranged from 21.58 to 28.63 µmol ferulic acid equivalents/g dry matter. All flour and food preparations exhibited effective inhibition of radicals, reducing power, ferrous ion chelating activity, and antioxidant activity in the β-carotene/linoleate emulsion and the degree of activity depended on the processing conditions adopted in food *** prepared using steaming showed lower phenolic content and antioxidant activities in general than those of open-boiled counterparts. The addition of spices, namely garlic and cinnamon improved the phenolic contents and antioxidant activities of open-boiled porridges. The knowledge generated from this study may help to exploit the use of finger millets as a functional food ingredient to promote health and wellness.

关键词： Antioxidants Parboiling Roasting Pittu Porridges

Dissection of the genetic architecture for tassel branch number by QTL analysis in two related populations in maize

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Journal of Integrative Agriculture 2017年第7期16卷 1432-1442页

作者： CHEN Zheng-jie YANG Cong TANG Deng-guo ZHANG Lei ZHANG Ling QU Jing-tao LIU Jian Maize Research Institute Sichuan Agricultural UniversityChengdu 611130P.R.China

Tassel branch number （TBN） is the principal component of maize tassel inflorescence architecture and is a typical quan- titative trait controlled by multiple genes. The main objective of this research was to detect quantitative trait loci （QTLs） for TBN. The maize inbred line SICAU1212 was used as the common parent to develop BC1S1 and recombinant inbred line （RIL） populations with inbred lines 3237 and B73, respectively. The two related populations consisted of 123 and 238 lines, respectively. Each population was grown and phenotyped for TBN in two environments. Eleven QTLs were detected in the BC1S1 population, located on chromosomes 2, 3, 5, and 7, accounted for 4.45-26.58% of the phenotypic variation. Two QTLs （qB11Jtbn2-1, qB12Ctbn2-1, qBJtbn2-1; q11JBtbn5-1, qB12Ctbn5-1, qBJtbn5-1） that accounted for more than 10% of the phenotypic variation were identified. Three QTLs located on chromosomes 2, 3 and 5, exhibited stable expres- sion in the two environments. Ten QTLs were detected in the RIL population, located on chromosomes 2, 3, 5, 8, and 10, accounted for 2.69-13.58% of the TBN variation. One QTL （qR14Dtbn2-2） explained 〉10% of the phenotypic variation. One common QTL （qB12Ctbn2-2, qR14Dtbn2-2, qRJtbn2-2） was detected between the two related populations. Three pairs of epistatic effects were identified between two loci with or without additive effects and accounted for 1.19-4.26% of the phenotypic variance. These results demonstrated that TBN variation was mainly caused by major effects, minor effects and slightly modified by epistatic effects. Thus, identification of QTL for TBN may help elucidate the genetic basis of TBN and also facilitate map-based cloning and marker-assisted selection （MAS） in maize breeding programs.

关键词： QTL tassel branch number related populations epistatic effects