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智能化采矿的安全保障与风险控制研究

中国高新科技 2024年第11期 45-47页

作者：董立华伊犁新矿煤业有限责任公司新疆伊犁835000

本文基于智能传感器、人工智能算法和大数据分析,建立了一套全面的安全保障与风险控制系统。针对智能化采矿的安全保障与风险控制,运用智能算法实现风险识别与预警。在事故发生后,系统能够记录并分析事故前的传感器数据,为深入事故分析... 详细信息

本文基于智能传感器、人工智能算法和大数据分析,建立了一套全面的安全保障与风险控制系统。针对智能化采矿的安全保障与风险控制,运用智能算法实现风险识别与预警。在事故发生后,系统能够记录并分析事故前的传感器数据,为深入事故分析提供依据,进而制定有效的改进措施。研究结果显示,采矿效率提高、事故发生率降低和人员伤亡率减少,为智能化采矿的安全推进提供了实质性的支持。

关键词：智能化采矿安全保障风险控制

浅谈在高等数学教学中培养学生举一反三的能力

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科技风 2024年第15期 38-40页

作者：董丽华南京工业大学数理科学学院江苏南京211816

对于大学数学而言,提高教师的授课水平,培养学生的理性数学思维和创新能力,是当前大学数学的教学目的。本文通过对高等数学中比较典型的概念和案例等知识点分析探讨,列举出教师在高等数学教学中培养学生举一反三能力的方法。通过这些方... 详细信息

对于大学数学而言,提高教师的授课水平,培养学生的理性数学思维和创新能力,是当前大学数学的教学目的。本文通过对高等数学中比较典型的概念和案例等知识点分析探讨,列举出教师在高等数学教学中培养学生举一反三能力的方法。通过这些方法,教师要做到引导学生主动思考,培养学生学会对所学知识点迁移类推,从多角度分析问题,最终做到触类旁通、举一反三。

关键词：高等数学教学举一反三

维普期刊数据库博看期刊

Weak generalized self-shrinking generators

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Journal of Systems Engineering and Electronics 2007年第2期18卷 407-411页

作者： dong lihua Hu Yupu The Key Lab. of Computer Networks and Information Security the Ministry of Education Xidian Univ. Xi'an 710071 P. R. China

The security of certain classes of the generalized self-shrinking sequence （GSS） generators is analyzed. Firstly, it is shown that the security of these GSS generators is equivalent to the security of the GSS generators of the class-1, after which two effective key recovery attacks on the GSS generators of the class-1 are developed to evaluate their security.

关键词： Cryptography Stream cipher, Key recovery attacks Generalized self-shrinking sequence.

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船用低温钢焊接材料的研发与腐蚀方法评价

中国腐蚀与防护学报 2024年第4期44卷 957-964页

作者：林一刘涛郭彦兵阮晴郭章伟董丽华中国核能电力股份有限公司北京100000 上海海事大学海洋科学与工程学院海洋材料研究院上海201306

海洋工程焊接结构件的腐蚀性能对海洋工程的安全性影响巨大,但目前缺乏科学和系统的评价方法。基于此,本文采用了两种焊接结构件,其焊料合金成分不同,将其浸泡于含腐蚀性细菌的人造海水中,并对其进行腐蚀性能评价。研究表明宏观测试方法... 详细信息

海洋工程焊接结构件的腐蚀性能对海洋工程的安全性影响巨大,但目前缺乏科学和系统的评价方法。基于此,本文采用了两种焊接结构件,其焊料合金成分不同,将其浸泡于含腐蚀性细菌的人造海水中,并对其进行腐蚀性能评价。研究表明宏观测试方法(如电化学阻抗法,失重法等)与微观测试方法(微区电化学扫描)所得到的结果并不完全一致。因此,在评价焊接结构件耐腐蚀性时,不能仅通过传统的电化学或失重等测试方法,还应使用微观电化学测试手段。根据焊接结构件的微观腐蚀性能,更佳准确的指导焊接结构件母材与焊材的搭配与选择,提高其整体耐海水腐蚀性能。

关键词：焊接结构件耐腐蚀性能腐蚀性细菌

Predictive control for mechanical system with backlash based on hybrid model

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Journal of Systems Engineering and Electronics 2009年第6期20卷 1301-1308页

作者： Dou lihua dong Lingxun Chen Jie Xia Yuanqing Dept. of Information Science and Technology Beijing Inst. of Technology Beijing 100081 P. R. China

The mechanical system with backlash is distinguished between a＂backlash mode＂and a＂contact mode＂.The inherent switching between the two operating modes makes the system a prime example of hybrid *** eliminating the bad effect of backlash, a piecewise affine（PWA） model of the mechanical servo system with backlash is *** optimal control of constrained PWA system is obtained by taking advantage of model predictive control（MPC） method, and the explicit solution of MPC in a look-up table form is figured out by combining the dynamic programming and multi-parametric quadratic programming, thereby establishing an explicit hybrid model predictive ***, a piecewise quadratic（PWQ） function for guaranteeing the stability of closed-loop control is found by formulating the search of PWQ function as a semi-definite programming *** the tracking experiments, it is demonstrated that the explicit hybrid model predictive controller has a good traction control effect on the mechanical system with *** error meets the demands of real ***, compared to the direct on-line computation, the computation burden is reduced by the explicit solution, thereby being suitable for real-time control of system with short sampling time.

关键词： predictive controller hybrid model hybrid control backlash mode.

功能性超疏水涂层在极地抗冰领域的应用研究进展

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中国腐蚀与防护学报 2024年第1期44卷 1-14页

作者：姜伯晨类延华张玉良李晓峰刘涛董丽华上海海事大学海洋科学与工程学院上海201306 江苏航运职业技术学院智能制造与信息学院南通226000

就结冰机理、超疏水表面浸润理论和界面的抗冰特性进行了综述,然后对不同方法制备的超疏水涂层在抗冰领域的应用进行了讨论和总结。最后,针对超疏水涂层在除冰方面存在的缺陷,提出了具有光热、电热等功能性超疏水涂层策略,并全面介绍了... 详细信息

就结冰机理、超疏水表面浸润理论和界面的抗冰特性进行了综述,然后对不同方法制备的超疏水涂层在抗冰领域的应用进行了讨论和总结。最后,针对超疏水涂层在除冰方面存在的缺陷,提出了具有光热、电热等功能性超疏水涂层策略,并全面介绍了目前的研究现状。

关键词：抗冰涂层超疏水光热除冰电热除冰极地

Corrosion Behavior of Plasma Transferred Arc Fe-based Coating Reinforced by Spherical Tungsten Carbide in Hydrochloric Acid Solutions

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Journal of Wuhan University of Technology(Materials Science) 2020年第2期35卷 299-309页

作者： dong Yaohua FAN Li CHEN Haiyan dong lihua YIN Yansheng SUN Fanghong College of Ocean Science and Engineering Shanghai Maritime UniversityShanghai 201306China College of Mechanical and Elec-tronic Engineering Shanghai Jian Qiao UniversityShanghai 201306China School of Mechanical Engineering Shanghai Jiaotong Uni-versityShanghai 200240China

Fe-based coatings reinforced by spherical tungsten carbide were deposited on 304 stainless steel using plasma transferred arc(PTA) *** composition and phase microstructure of the coatings were evaluated using scanning electron microscopy(SEM),energy dispersive spectrometer(EDS) and X-ray diffraction(XRD).The corrosion behaviors of the coatings in 0.5 mol/L HCl solution were studied using polarization curve and electrochemical impedance spectroscopy(EIS) *** experimental results shows that the tungsten carbide improves the corrosion resistance of the Fe-based alloy coating,but increase in the mass fraction of tungsten carbide leads to increasing amount of defects of holes and cracks,which results in an adverse effect on the corrosion *** defects are mainly present on the tungsten carbide but also extend to the Fe-based *** tungsten carbide,acting as a cathode,and binding material of Fe-based alloy,acting as an anode,create a galvanic corrosion *** binding material is preferentially corroded and causes the degradation of the coating.

关键词： plasma transferred arc(PTA) spherical tungsten carbide Fe-based alloys corrosion resistance electrochemical impedance spectroscopy

Evaluation of clinical application of ESICM acute gastrointestinal injury grading system： a single-center observational study

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Chinese Medical Journal 2014年第10期127卷 1833-1836页

作者： Zhang dong Li Nan dong lihua Fu Yao Liu Zhongmin Wang Yushan Intensive Care Unit First Hospital Jilin University Changchun Jilin 130021 China

Background In 2012,the working group on abdominal problems of the European Society of Intensive Care Medicine （ESICM） proposed a definition and also guidelines for the grading system and treatment of acute gastrointestinal injury （AGI）.Until now,clinical reports on this topic have not been available,and the practicality of using the AGI grading system requires further validation in the ***,we conducted this study to evaluate the feasibility of utilizing the current AGI grading system in a clinical environment,and to provide evidence for its usefulness in assessing the severity and prognosis of critically ill patients with gastrointestinal *** A total of 133 patients were examined for the presence or absence of AGI,their scores on the Acute Physiology and Chronic Health Evaluation （APACHE） Ⅱ and Lausanne Intestinal Failure Estimation （LIFE） test,and 28 days *** presence and severity of AGI was based on guidelines provided by the *** patients were assigned to a NOAGI group （n=50） or an AGI group （n=83）.The AGI group was then further divided into three subgroups,consisting ofAGI Ⅰ （risk group,n=38）,AGI Ⅱ （gastrointestinal dysfunction group,n=33） and AGI Ⅲ＋AGI Ⅳ （gastrointestinal failure group,n=12）.These subgroups were then compared for differences in AGI *** There were no statistically significant differences between the AGI group and the NO-AGI group in terms of age,gender,APACHE Ⅱ score or LIFE score （P ＞ 0.05）; however,the two groups showed a significant difference in their respective rates of 28 days mortality （32.5％ in the AGI group vs.8.0％ in the NO-AGI group （P ＜ 0.05））.Patients in the three AGI subgroups showed significant differences in their 28 d mortality rates,APACHE Ⅱ,and LIFE *** grading system showed strong positive correlations with APACHE Ⅱ and LIFE scores （P ＜ 0.05）.Conclusions The currentAGI grading system can be used to identify and evaluate gastrointestinal dysfunction in criticall

关键词： acute gastrointestinal injury multiple organ dysfunction syndrome gastrointestinal dysfunction prognosis

Wear Properties of Plasma Transferred Arc Fe-based Coatings Reinforced by Spherical WC Particles

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Journal of Wuhan University of Technology(Materials Science) 2019年第2期34卷 433-439页

作者：范丽董耀华 CHEN Haiyan dong lihua YIN Yansheng College of Mechanical and Electronic Engineering Shanghai Jian Qiao University School of Mechanical Engineering Shanghai Jiaotong University College of Ocean Science and Engineering Shanghai Maritime University

Fe-based coatings reinforced by spherical WC particles were produced on the 304 stainless steel by plasma transferred arc(PTA) to enhance the surface wear properties. Three different Fe/WC composite powder mixtures containing 0 wt%, 30 wt%, and 60 wt% of WC were investigated. The microstructure and phase composition of the Fe/WC composite PTA coatings were evaluated systemically by using scanning electron microscope(SEM) and X-ray diffraction(XRD). The wear properties of the three fabricated PTA coatings were investigated on a BRUKER UMT TriboLab. The morphologies of the worn tracks and wear debris were characterized by using SEM and 3 D non-contract profiler. The experimental results reveal that the microhardness on the cross-section and the wear resistance of the fabricated coatings increase dramatically with the increasing adding WC contents. The coating containing 60 wt% of WC possesses excellent wear resistance validated by the lower coefficients of friction(COF), narrower and shallower wear tracks and smaller wear rate. In the pure Fe-based coating, the main wear mechanism is the combination of adhesion and oxidative wear. Adhesive and two-body abrasive wear are predominated in the coating containing 30 wt% of WC, whereas threebody abrasion wear mechanism is predominated in the coating containing 60 wt% of WC.

关键词： plasma transferred arc(PTA) metal matrix composite coatings(MMCs) spherical tungsten carbide Fe-based alloys wear resistance