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线性连续重复过程的区域极点约束迭代学习控制

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华南理工大学学报（自然科学版） 2020年第1期48卷 114-122页

作者：汪磊杨慧中陶洪峰 wojciech Paszke 江南大学教育部轻工过程先进控制重点实验室江苏无锡214122 Institute of Control and Computation Engineering University of Zielona Goraul.Szafrana 265-516 Zielona GoraPoland

现有的迭代学习控制研究关注于迭代学习控制系统在迭代批次方向的鲁棒收敛性,对控制系统在时间方向上的性能关注较少,没有展现出控制系统的动态特征。文中研究了有限频域范围线性连续重复过程在区域极点约束下的迭代学习控制问题。首先... 详细信息

现有的迭代学习控制研究关注于迭代学习控制系统在迭代批次方向的鲁棒收敛性,对控制系统在时间方向上的性能关注较少,没有展现出控制系统的动态特征。文中研究了有限频域范围线性连续重复过程在区域极点约束下的迭代学习控制问题。首先,结合二维系统理论,在时域中建立迭代学习控制系统的二维连续Roesser模型;然后基于Kalman-Yakubovich-Popov(KYP)引理,分析迭代学习控制系统的跟踪性能和区域极点约束问题;进而以线性矩阵不等式的形式给出控制器存在的充分条件,保证系统在批次方向和时间方向的性能,并将结果扩展到结构不确定性模型中;最后,通过典型的跟踪伺服系统执行机构的控制仿真验证了设计方案的有效性和可行性。

关键词：线性连续重复过程区域极点约束迭代学习控制 Kalman-Yakubovich-Popov引理

天然状态下多年冻土区活动层厚度研究进展与展望

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冰川冻土 2023年第2期45卷 558-574页

作者：罗栋梁金会军吴青柏 Olga MAKARIEVA 田世民康建芳王金牛彭小清 wojciech DOBIŃSKI 陈方方中国科学院西北生态环境资源研究院冻土工程国家重点实验室甘肃兰州730000 东北林业大学土木工程学院黑龙江哈尔滨150040 Institute of Earth Sciences St.Petersburg UniversitySt.Petersburg 199034Russia 黄河水利科学研究院河南郑州450003 国家冰川冻土沙漠科学数据中心甘肃兰州730000 中国科学院成都生物研究所四川成都610041 兰州大学资源环境学院甘肃兰州730000 Institute of Earth Sciences Faculty of Natural ScienceUniversity of SilesiaSosnowiec 41-200Poland 中国科学院大学北京100049

活动层作为多年冻土区水热物理和力学动态最活跃的近地表层,是供给高寒植物生长所需水分和营养物质的关键区,是多年冻土与大气圈、土壤圈进行能水和物质交换的主要通道,也是微生物活动最频繁和生物地球化学循环最关键的冷生土壤层。近... 详细信息

活动层作为多年冻土区水热物理和力学动态最活跃的近地表层,是供给高寒植物生长所需水分和营养物质的关键区,是多年冻土与大气圈、土壤圈进行能水和物质交换的主要通道,也是微生物活动最频繁和生物地球化学循环最关键的冷生土壤层。近几十年来,在气候变暖和人类活动增强影响下,多年冻土区活动层厚度(ALT)普遍增加,对寒区环境与冻土工程产生了不利影响。本文对影响天然状态下ALT空间分异的宏观地质地理和微观局地因子、ALT的野外测量和模拟计算方法、ALT对气候变化的响应特征进行了回顾,并探讨了ALT变化对高寒生态环境的影响。研究表明:太阳辐射及其重分布和下垫面的复合作用是ALT空间分异的主因,在其他因素和条件一致时,高程多年冻土下界和纬度多年冻土南界附近的ALT较厚;近三十年来ALT积极响应气候变暖,随气温升高而增加,但区域差异明显,中纬高海拔和山地多年冻土区ALT大部分呈显著增加趋势,而高纬富含冰多年冻土区ALT因地下冰融化下沉,一定程度上抵消了因气候变暖而增加的部分。本文还展望了ALT未来研究方向,认为应聚焦ALT精准模拟制图、ALT变化的自适应机制、ALT变化对生物地球化学循环的影响和ALT变化对水文水资源的影响等四个方面。

关键词：多年冻土活动层厚度(ALT) 气候变化空间分异生态水文效应

Implementation of Non-Newtonian Fluid Properties for Compressible Multiphase Flows in OpenFOAM

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Open Journal of Fluid Dynamics 2020年第2期10卷 135-150页

作者： Stefan Westermaier wojciech Kowalczyk Chair of Mechanics and Robotics University of Duisburg-Essen Essen Germany

The paper presents the implementation of non-Newtonian fluid properties for compressible multiphase solver in the open source framework OpenFOAM. The transport models for Power Law, Cross Power Law, Casson, Bird-Carreau and Herschel-Bulkley fluids were included in the thermophysical model library. Appropriate non-Newtonian liquids have been chosen from literature, and pressure driven test simulations are carried out. Therefore, the solver compressibleInterFoam is used to compute air-liquid mixture flows over a backward facing step. A validation of the novel models has been performed by means of a sample-based comparison of the strain rate viscosity relation. The theoretical rheological properties of the selected liquids agree well with the results of the simulated data.

关键词： OpenFOAM Non-Newtonian Fluid Multiphase Flow Compressible Flow

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Journal of Geriatric Cardiology 2018年第11期15卷 657-665页

作者： Aleksandra Stańska Dariusz Jagielak Maciej Kowalik Maciej Brzeziński Rafal Pawlaczyk Jadwiga Fijalkowska wojciech Karolak Jan Rogowski Peter Bramlage Department of Cardiac and Vascular Surgery Medical University of Gdansk Gdansk Poland Department of Radiology Medical University of Gdansk Gdansk Poland Institute far Pharmacology and Preventive Medicine Cloppenburg Germany

Objective To evaluate short- and long-term changes in quality of life (QoL) in patients undergoing transcatheter aortic valve implantation (TAVI) and to assess differences in patient QoL when using the TAVI transaortic (TAVI TAo) approach compared with the transfemoral approach (TAVI TF) and surgical aortic valve replacement (SAVR). Methods Ninety-seven patients were assessed. Thirty-two patients underwent TAVI TAo, 31 underwent TAVI TF and 34 patients underwent SAVR. QoL was assessed using the EQ-5D-3L questionnaire at baseline, after one month and one year. Results Mean patient age was 80 years (range, 61–92 years) and the mean logistic EuroSCORE was 12.45%(range, 1.39%?78.98%). Declared health state at baseline was significantly lower in TAVI TF (P < 0.001) and after one month there were no differences between the three groups (P = 0.99). After one year, SAVR patient results of the EQ-5D-3L index value were lower in comparison to both TAVI patient groups (P < 0.05). The analysis also showed significant differences between the results of EQ-5D-3L index value over the one month and one year follow-up (TAVI TAo, P < 0.001;TAVI TF, P < 0.05;SAVR, P < 0.05). In all groups, the values significantly increased after one-month and one-year of follow-up in comparison to baseline value. Significant differences were also demonstrated between Visual Analogue Scale values (VAS). Conclusions A significant improvement in QoL was observed in all three patient groups. Regardless of the TAVI approach, EQ-5D-3L and VAS values were significantly increased after one-month and one-year follow up;the SAVR patients however, reported lower health status when compared to the TAVI patients.

关键词： Aortic valve stenosis Aortic valve replacement The elderly Transcatheter aortic valve implantation Quality of life

Potential for carbon sequestration in reclaimed mine soil on reforested surface mining areas in Poland

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Natural Science 2010年第9期2卷 1015-1021页

作者： Marcin Pietrzykowski wojciech Krzaklewski 不详

Reclaimed mine soils (RMS) which develop on post-mining sites play significant role in Carbon sequestration in new ecosystems, especially in local range on areas disturbed by human activity. This study presents the potential for Carbon sequestration in RMS developing on 3 post sur- face mining areas in Poland (Central Europe) reforested with Scots pine (Pinus sylvestris L). Research was conducted on waste heaps and quarry which accompany open cast lignite, sul- fur, and sand mining. Control plots were arrang- ed in managed pine forests on natural sites in the surrounding area. The results shows high Carbon accumulation in RMS, estimated on 16.77 Mg?ha-1 in poor (oligotrofic) soils on Quaternary sands on sand quarry and up to 65.03 Mg?ha-1 on external waste heap after Sulfur sur- face mining exploitation on Quaternary sands mixed with Tertiary clays. These results were very similar to natural forest soils on control plots. Potential rate of Carbon sequestration in RMS was estimated on 0.73 (on the poorest sa- ndy soils on quarry) to 2.17 Mg?ha-1?yr-1 (on potentially abundant sandy-clayish soils on Sulfur waste heap), and 5.26 Mg?ha-1?yr-1 (on Tertiary sands substrate soils on lignite mining waste heap). In conslusion the average Carbon accu- mulation in RMS was estimated on 41 Mg?ha-1 and Carbon sequestration rate was 1.45 Mg? ha-1?yr-1. According to the result of this study and range of post-mining areas reclaimed to forestry in Poland (ca 15000 ha) total Carbon accumulation in RMS was estimated on 615 × 103 Mg and potential Carbon sequestration rate in new ecosystems on 21.75 × 103 Mg?ha-1?yr-1. However, the main factors affecting Carbon sequestration and protection in RMS under tree stand were substrate, percentage of clay and silt sized fraction, in order to formulate guidelines for sustainable management of post-mining ec- osystem, further study must be continue for be- tter understanding.

关键词： Post-Mining Ecosystem Reclaimed Mine Soils Reforestation Carbon Sequestration

Safety of intrathecal injection of Wharton's jellyderived mesenchymal stem cells in amyotrophic lateral sclerosis therapy

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Neural Regeneration Research 2019年第2期14卷 313-318页

作者： Monika Barczewska Mariusz Grudniak Stanis?aw Maksymowicz Tomasz Siwek Tomasz O?dak Katarzyna Jezierska-Wo?niak Dominika G?adysz wojciech Maksymowicz Department of Neurology and Neurosurgery School of Medicine Collegium Medicum-University of Warmia and Mazury in Olsztyn University Clinical Hospital in Olsztyn Instytut Terapii Komórkowych w Olsztynie(Cell Therapies Institute FamiCord Group) Polski Bank Komórek Macierzystych (PBKM FamiCord Group) Department of Psychology Clinical Logopedics and Social Science in Medicine Faculty of Health Sciences Collegium Medicum-University of Warmia and Mazury in Olsztyn Department of Neurology and Neurosurgery Laboratory of Regenerative Medicine School of Medicine Collegium Medicum-University of Warmia and Mazury in Olsztyn

Animal experiments have confirmed that mesenchymal stem cells can inhibit motor neuron apoptosis and inflammatory factor expression and increase neurotrophic factor expression. Therefore, mesenchymal stem cells have been shown to exhibit prospects in the treatment of amyotrophic lateral sclerosis. However, the safety of their clinical application needs to be validated. To investigate the safety of intrathecal injection of Wharton's jelly-derived mesenchymal stem cells in amyotrophic lateral sclerosis therapy, 43 patients(16 females and 27 males, mean age of 57.3 years) received an average dose of 0.42 × 106 cells/kg through intrathecal administration at the cervical, thoracic or lumbar region depending on the clinical symptoms. There was a 2 month interval between two injections. The adverse events occurring during a 6-month treatment period were evaluated. No adverse events occurred. Headache occurred in one case only after first injection of stem cells. This suggests that intrathecal injection of Wharton's Jelly-derived mesenchymal stem cells is well tolerated in patients with amyotrophic lateral sclerosis. This study was approved by the Bioethical Committee of School of Medicine, University of Warmia and Mazury in Olsztyn, Poland(approval No. 36/2014 and approval No. 8/2016). This study was registered with the ***(identifier: NCT02881476)on August 29, 2016.

关键词： amyotrophic lateral sclerosis stem cells therapy intrathecal injections Wharton's jelly-derived mesenchymal stem cells adverse events safety cerebrospinal fluid neural regeneration

Simultaneous Gravitational and Refractive Lensing

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International Journal of Astronomy and Astrophysics 2012年第2期2卷 76-81页

作者： wojciech T. Chyla Applied Science Enterprise Warszawa Poland

The principal testing ground for general relativity is the observable Universe. Gravitational lensing is the leading observational technique that gives insight into the distribution of baryonic matter in the stellar, galactic and cosmological scale, as well as the distribution of dark matter and dark energy, due to their gravitational interaction. Interpretation of ever more precise observational data requires increasingly subtle analytical techniques. In this paper, I discuss a formalism that can handle a nonlinear superposition of gravitational and refractive lensing by a grouping of baryonic matter, dark matter and dark energy for a given distribution of those entities (i.e. for a given spacetime metric) and their refractive properties. The role of refraction in gravitational lensing is exemplified in the case of a microlensing event and a signature of such an effect is discussed.

关键词： Gravitational Lensing Microlensing Macrolensing Refraction

Comparative Transcriptomics of Early Meiosis in Arabidopsis and Maize

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Journal of Genetics and Genomics 2014年第3期41卷 139-152页

作者： Stefanie Dukowic-Schulze Anthony Harris Junhua Li Anitha Sundararajan Joann Mudge Ernest F.Retzel wojciech P.Pawlowski Changbin Chen Department of Horticultural Science University of Minnesota College of Life Sciences Henan Normal University National Center for Genome Resources Department of Plant Breeding and Genetics Cornell University

Though sexually reproductive plants share the same principle and most processes in meiosis, there are distinct features detectable. To address the similarities and differences of early meiosis transcriptomes from the dicot model system Arabidopsis and monocot model system maize, we performed comparative analyses of RNA-seq data of isolated meiocytes, anthers and seedlings from both species separately and via orthologous genes. Overall gene expression showed similarities, such as an increased number of reads mapping to unannotated features, and differences, such as the amount of differentially expressed genes. We detected major similarities and differences in functional annotations of genes up-regulated in meiocytes, which point to conserved features as well as unique features. Transcriptional regulation seems to be quite similar in Arabidopsis and maize, and we could reveal known and novel transcription factors and cis- regulatory elements acting in early meiosis. Taken together, meiosis between Arabidopsis and maize is conserved in many ways, but displays key distinctions that lie in the patterns of gene expression.

关键词： Meiosis Transcriptome RNA-seq Meiocytes Arabidopsis Maize

THE TRANSFORMED NONPARAMETRIC FLOOD FREQUENCY ANALYSIS

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Journal of Computational Mathematics 1994年第4期12卷 330-338页

作者： Kaz Adamowski(Department of Civil Engineering University of Ottawa, Ottawa, Canada)wojciech Feluch(Institute of Environmental Engineering , Technical University of Warsaw, Warsaw, Poland) University of Ottawa 加拿大 Technical University of Warsaw 波兰

The nonparametric kernel estimation of probability density function (PDF) pro-vides a uniform and accurate estimate of flood frequency-magnitude ***, the kernel estimate has the disadvantage that the smoothing factor h is estimate empirically and is not locally adjusted, thus possibly resulting in deteri oration of density estimate when PDF is not smooth and is heavy-tailed. Such a problem can be alleviate by estimating the density of a transformed random vari able, and then taking the inverse transform. A new and efficient circular transform is proposed and investigated in this paper

关键词： TRT Res THE TRANSFORMED NONPARAMETRIC FLOOD FREQUENCY ANALYSIS