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三配流窗口轴向柱塞泵非死点过渡区特性研究

机械设计与制造 2024年第9期 335-339页

作者：申煜玺王君张晓刚太原理工大学机械与运载工程学院山西太原030024 太原理工大学新型传感器与智能控制教育部重点实验室山西太原030024

三配流窗口轴向柱塞泵有效地解决了在泵控单出杆液压缸两腔流量不同造成的不配对问题。但是三配流窗口轴向柱塞泵中的非死点过渡区存在流量脉动和压力冲击问题,针对此问题提出在非死点过渡区和上死点过渡区开设阻尼孔,两个阻尼孔通过孔... 详细信息

三配流窗口轴向柱塞泵有效地解决了在泵控单出杆液压缸两腔流量不同造成的不配对问题。但是三配流窗口轴向柱塞泵中的非死点过渡区存在流量脉动和压力冲击问题,针对此问题提出在非死点过渡区和上死点过渡区开设阻尼孔,两个阻尼孔通过孔道连接,平衡非死点过渡区与上死点过渡区压力。根据配流面积函数,在AMEsim软件里面搭建柱塞泵模型,仿真有无阻尼孔,开设阻尼孔的大小和位置等参数对柱塞泵的流量和压力的影响,确定出合适的配流盘结构。结果表明,开设阻尼孔油道可以减小过渡区压力变化梯度,降低柱塞泵在过渡区的压力冲击和流量脉动,同时减小泄漏和油液压缩耗能,提高容积效率。

关键词：三配流窗口轴向柱塞泵阻尼槽配流盘非死点过渡区流量脉动压力冲击

2023年12月18日甘肃积石山M_(S)6.2地震多点源地震矩张量反演研究

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地震 2024年第2期44卷 169-177页

作者：刘俊清张小刚张宇蔡宏雷陈卓包秀敏吉林建筑大学测绘与勘查工程学院吉林长春130119 吉林省基础地理信息中心吉林省测绘档案资料馆吉林长春130062 吉林省地震局吉林长春130117 辽宁省地震局沈阳地震监测中心站辽宁沈阳110161

基于区域宽频带数字地震台网观测到的地震记录,采用多点源地震矩张量反演方法对2023年甘肃积石山M_(S)6.2地震进行了地震矩张量反演研究。结果显示,该地震震源机制解的NE倾的节面(走向312°,倾角48°,滑动角76°)为发震断裂,主体地震矩... 详细信息

基于区域宽频带数字地震台网观测到的地震记录,采用多点源地震矩张量反演方法对2023年甘肃积石山M_(S)6.2地震进行了地震矩张量反演研究。结果显示,该地震震源机制解的NE倾的节面(走向312°,倾角48°,滑动角76°)为发震断裂,主体地震矩从震源向地表沿滑动矢量的方向(方位角236°,倾伏角40.5°)释放,主破裂持续时间约为5.8 s,与此同时,地震破裂区断层面上发生了次级的双侧破裂。

关键词：积石山6.2级地震地震矩张量多点源发震构造

Classification of knowledge graph completeness measurement techniques

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Journal of Systems Engineering and Electronics 2024年第1期35卷 154-162页

作者： zhang Ying xiao gang Institute of Systems Engineering Academy of Military SciencesBeijing 100107China

At present,although knowledge graphs have been widely used in various fields such as recommendation systems,question and answer systems,and intelligent search,there are always quality problems such as knowledge omissions and *** assessment and control,as an important means to ensure the quality of knowledge,can make the applications based on knowledge graphs more complete and more accurate by reasonably assessing the knowledge graphs and fixing and improving the quality problems at the same ***,as an indispensable part of the knowledge graph construction process,the results of quality assessment and control determine the usefulness of the knowledge *** them,the assessment and enhancement of completeness,as an important part of the assessment and control phase,determine whether the knowledge graph can fully reflect objective phenomena and reveal potential connections among *** this paper,we review specific techniques of completeness assessment and classify completeness assessment techniques in terms of closed world assumptions,open world assumptions,and partial completeness *** purpose of this paper is to further promote the development of knowledge graph quality control and to lay the foundation for subsequent research on the completeness assessment of knowledge graphs by reviewing and classifying completeness assessment techniques.

关键词： quality assessment completeness assessment closed world assumptions open world assumption partial completeness assumption

Effect of Environmental Factors on Electrochemical Behavior of X70 Pipeline Steel in Simulated Soil Solution

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Journal of Iron and Steel Research International 2009年第6期16卷 52-57页

作者： zhang Liang LI xiao-gang DU Cui-wei School of Materials Science and Engineering University of Science and Technology Beijing Beijing 100083 China

Potentiodynamic polarization measurement was used to investigate the effects of temperature, dissolved ox- ygen concentration and pH on the electrochemical behavior of X70 pipeline steel in simulated solution according to the orthogonal testing method. The results showed that temperature, dissolved oxygen concentration and pH had great influence on corrosion current density （icorr） of X70 steel. Corrosion current density of X70 steel was most influenced by dissolved oxygen concentration in simulated solution. The corrosion degree of X70 steel was the least under the environment of low temperature, deficient oxygen and weak acid.

关键词： X70 pipeline steel potentiodynamic polarization measurement orthogonal testing corrosion current density

TGF-β/Smads信号通路在心力衰竭心肌纤维化中的作用及中医药干预研究现状

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中国临床药理学杂志 2024年第3期40卷 444-448页

作者：霍耀辉张静周立蓉张晓刚高永泽刘黎明刘凯甘肃中医药大学中西医结合学院甘肃兰州730000 甘肃省中心医院神经内科甘肃兰州730070

在心力衰竭(HF)进展过程中,转化生长因子-β(TGF-β)/Smads信号通路的异常转导是HF心肌纤维化(MF)的重要机制。TGF-β是MF的关键因子,在HF MF过程中处于过度表达状态。Smads是TGF-β下游的主要效应因子,TGF-β/Smads通路诱导肌成纤维细... 详细信息

在心力衰竭(HF)进展过程中,转化生长因子-β(TGF-β)/Smads信号通路的异常转导是HF心肌纤维化(MF)的重要机制。TGF-β是MF的关键因子,在HF MF过程中处于过度表达状态。Smads是TGF-β下游的主要效应因子,TGF-β/Smads通路诱导肌成纤维细胞异常增殖,加重心肌细胞外基质沉积,使心脏组织抗纤维化能力减弱,在HF MF的发病机制中发挥复杂作用。中医药在防治HF MF方面具有明确抑制心肌胶原沉积、抗心肌纤维化、保护心肌和改善心脏功能等功效。TGF-β/Smads通路是中药单体、中药复方、中成药发挥HF心肌保护作用的关键通路之一。本文对近10年来中医药干预TGF-β/Smads通路治疗HF MF现有的实验研究成果进行综述,以期为HF MF的防治及新药开发提供理论依据。

关键词：中医药转化生长因子-β/Smads信号通路心力衰竭心肌纤维化作用机制

How to implement a knowledge graph completeness assessment with the guidance of user requirements

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Journal of Systems Engineering and Electronics 2024年第3期35卷 679-688页

作者： zhang Ying xiao gang Institute of Systems Engineering Academy of Military SciencesBeijing 100107China

In the context of big data, many large-scale knowledge graphs have emerged to effectively organize the explosive growth of web data on the Internet. To select suitable knowledge graphs for use from many knowledge graphs, quality assessment is particularly important. As an important thing of quality assessment, completeness assessment generally refers to the ratio of the current data volume to the total data *** evaluating the completeness of a knowledge graph, it is often necessary to refine the completeness dimension by setting different completeness metrics to produce more complete and understandable evaluation results for the knowledge ***, lack of awareness of requirements is the most problematic quality issue. In the actual evaluation process, the existing completeness metrics need to consider the actual application. Therefore, to accurately recommend suitable knowledge graphs to many users, it is particularly important to develop relevant measurement metrics and formulate measurement schemes for completeness. In this paper, we will first clarify the concept of completeness, establish each metric of completeness, and finally design a measurement proposal for the completeness of knowledge graphs.

关键词： knowledge graph completeness assessment relative completeness user requirement quality management

The Development of Advanced HSLA Steel in Angang in Low Carbon Age

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Journal of Iron and Steel Research International 2011年第S1期18卷 22-28页

作者： zhang xiao-gang (Anshan Iron and Steel Group Corporation,Anshan 114001,Liaoning,China) Anshan Iron & Steel Grp Corp Anshan 114001 Liaoning Peoples R China

The structure steel industry has experienced a revolution during four *** the challenge of global change in climate and environments,the higher strength,higher ductility steels,environment friendly steel were *** R and D for high strength steel production and application in Angang has made impressive *** more attention had been paid on the development of new type high strength steels with higher strength and better *** multi-phase microstructure,lower y/s,and corrosion resistance performance structure steel results in new generation advanced high strength steel which have properties that are often much superior to those exhibited by the old *** paper presents a general review of new generation high strength steel research and development in Angang and predicts the development for advanced high strength steel in the foreseeable future.

关键词： high strength steel energy conservation emission reduction

Treatment of Lung Cancer with Orally Administered Chinese Herbal Medicine: An Evidence Map between 1970–2020

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Chinese Journal of Integrative Medicine 2022年第10期28卷 930-938页

作者： GUI Yue-rong zhang Ying WANG Xue-qian FAN Bing-jie LI Jing-lei zhang Lan-xin FAN Fen CAO Kang-di zhang xiao-gang HOU Wei Department of Oncology Guang'anmen HospitalChina Academy of Chinese Medical SciencesBeijing(100053)China Cancer Project Team of China Center for Evidence-Based Traditional Chinese Medicine Beijing(100053)China

Objective: Through showing the full picture of double-arm controlled clinical research and systematic review evidence in the field of orally administrated Chinese herbal medicine(CHM) for treatment of lung cancer, to provide a reference for future clinical research and to indicate a direction for future systematic reviews. Methods: A comprehensive search of clinical controlled studies was performed regarding orally administered CHM treatment for lung cancer published from January 1970 to September 2020. The language was restricted to Chinese and English. Relevant data were extracted, the quality of systematic reviews was evaluated, and the research evidence was visually displayed. Results: Randomized controlled trials were the most common type of research design. The research sample sizes were typically small. Oral CHM showed certain curative advantages in treating lung cancer. The key stages in oral CHM intervention for lung cancer are chemotherapy, radiotherapy, and late palliative treatment. The advantageous outcomes of oral CHM treatment of lung cancer are the short-term efficacy, quality of life, and adverse reactions. The perioperative stage, overall survival, pharmacoeconomic evaluation, and Chinese medicine decoctions are weak research areas. Conclusions: CHM has staged and therapeutic advantages in treating lung cancer. The overall methodological quality is poor, and the level of evidence requires improvement. It is necessary to carry out large-scale, standardized, and higherquality research in the superior and weak areas of CHM treatment of lung cancer.

关键词： Chinese medicine clinical study evidence map evidence visualization lung cancer

Total ionizing dose effect modeling method for CMOS digital-integrated circuit

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Nuclear Science and Techniques 2024年第2期35卷 32-46页

作者： Bo Liang Jin-Hui Liu xiao-Peng zhang gang Liu Wen-Dan Tan Xin-Dan zhang School of Computer Science and Technology Xidian UniversityXi’an 710071China

Simulating the total ionizing dose(TID)of an electrical system using transistor-level models can be difficult and expensive,particularly for digital-integrated circuits(ICs).In this study,a method for modeling TID effects in complementary metaloxide semiconductor(CMOS)digital ICs based on the input/output buffer information specification(IBIS)was *** digital IC was first divided into three parts based on its internal structure:the input buffer,output buffer,and functional *** of these three parts was separately *** the IBIS model,the transistor V-I characteristic curves of the buffers were processed,and the physical parameters were extracted and modeled using *** the functional area,logic functions were modeled in VHDL according to the data sheet.A golden digital IC model was developed by combining the input buffer,output buffer,and functional area ***,the golden ratio was reconstructed based on TID experimental data,enabling the assessment of TID effects on the threshold voltage,carrier mobility,and time series of the digital *** experiments were conducted using a CMOS non-inverting multiplexer,NC7SZ157,and the results were compared with the simulation results,which showed that the relative errors were less than 2%at each dose *** confirms the practicality and accuracy of the proposed modeling *** TID effect model for digital ICs developed using this modeling technique includes both the logical function of the IC and changes in electrical properties and functional degradation impacted by TID,which has potential applications in the design of radiation-hardening tolerance in digital ICs.

关键词： CMOS digital-integrated circuit Total ionizing dose IBIS model Behavior-physical hybrid model Physical parameters