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Three-dimensional Extension of the Unit-Feature Spatial Classification Method for Cloud Type 被引量:1
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作者 张成伟 郁凡 +1 位作者 王晨曦 杨建宇 《Advances in Atmospheric Sciences》 SCIE CAS CSCD 2011年第3期601-611,共11页
We describe how the Unit-Feature Spatial Classification Method(UFSCM) can be used operationally to classify cloud types in satellite imagery efficiently and conveniently.By using a combination of Interactive Data Lang... We describe how the Unit-Feature Spatial Classification Method(UFSCM) can be used operationally to classify cloud types in satellite imagery efficiently and conveniently.By using a combination of Interactive Data Language(IDL) and Visual C++(VC) code in combination to extend the technique in three dimensions(3-D),this paper provides an efficient method to implement interactive computer visualization of the 3-D discrimination matrix modification,so as to deal with the bi-spectral limitations of traditional two dimensional(2-D) UFSCM.The case study of cloud-type classification based on FY-2C satellite data (0600 UTC 18 and 0000 UTC 10 September 2007) is conducted by comparison with ground station data, and indicates that 3-D UFSCM makes more use of the pattern recognition information in multi-spectral imagery,resulting in more reasonable results and an improvement over the 2-D method. 展开更多
关键词 cloud-type classification unit-feature spatial classification method three dimensions
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Type selection and maintenance of the control system of large-scale air separation units
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作者 DONG Zhenning 《Baosteel Technical Research》 CAS 2009年第3期13-17,共5页
Based on the practice of Baosteel' s 60000 m3/h air separation unit (ASU) ,which is the first domestically- integrated unit of such a scale, this paper studies the principles of type selection of the distribution c... Based on the practice of Baosteel' s 60000 m3/h air separation unit (ASU) ,which is the first domestically- integrated unit of such a scale, this paper studies the principles of type selection of the distribution control system (DCS). It discusses the design of the unit's control system,which involves a compressor system,a purification system (molecular sieving), a turbo expansion system and an air separation system. The final part of the paper discusses the maintenance and future development of the ASU control system at Baosteel. 展开更多
关键词 air separation unit control system type selection of distribution control system
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Weighted composition operators from F(p,q,s) spaces to Bers-type spaces in the unit ball 被引量:2
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作者 LU Xiao-fen 《Applied Mathematics(A Journal of Chinese Universities)》 SCIE CSCD 2009年第4期462-472,共11页
This paper deals with the boundedness and compactness of the weighted composition operators from the F(p, q, s) spaces, including Hardy space, Bergman space, Qp space, BMOA space, Besov space and α-Bloch space, to ... This paper deals with the boundedness and compactness of the weighted composition operators from the F(p, q, s) spaces, including Hardy space, Bergman space, Qp space, BMOA space, Besov space and α-Bloch space, to Bers-type spaces Hv^∞( or little Bers-type spaces Hv,o∞ ), where v is normal. 展开更多
关键词 F(p Q s) space Bers-type space weighted composition operator unit ball
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THE EFFECT OF SUBSTITUENT ON THE THERMAL PROPERTIES OF POLYESTERS CONSISTING OF AROMATIC TYPE SCHIFF BASE MESOGENIC UNITS AND POLYMETHYLENE SPACERS
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作者 Amar H.Al-Dujaili Iman F.Mustafa Amir T.Atto 《Chinese Journal of Polymer Science》 SCIE CAS CSCD 1995年第1期51-58,共8页
Polyesters consisting of substituted aromatic type Schiff base mesogenic unit andpolymethylene spacers were synthesized and their thermal transitions and liquid crystallineproperties were studied. The liquid crystalli... Polyesters consisting of substituted aromatic type Schiff base mesogenic unit andpolymethylene spacers were synthesized and their thermal transitions and liquid crystallineproperties were studied. The liquid crystalline behaviour has been characterized by differentialscanning calorimetry (DSC) and optical polarizing microscopy. Structural broadening bysubstitution of methoxy group in 2, 2' positions of the mesogenic core produce polymers withlower transition temperatures. Polymers synthesized from ortho and meta substituted phenylenediamine did not form a liquid crystal phase. 展开更多
关键词 Liquid crystal polymer Polyesters Aromatic type schiff base Mesogenic units SPACERS
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Counter-Rotating Type Horizontal-Axis Bidirectional Propellers for Tidal Stream Power Unit
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作者 Yuki Funami Yuji Nakanishi +2 位作者 Nak-Joong Lee Bin Huang Toshiaki Kanemoto 《Journal of Power and Energy Engineering》 2017年第7期34-44,共11页
Tidal stream power units with horizontal-axis propellers are one of promising technologies for generating the renewable green energy. The ebb and flow require that the power unit must operate in bidirectional tidal st... Tidal stream power units with horizontal-axis propellers are one of promising technologies for generating the renewable green energy. The ebb and flow require that the power unit must operate in bidirectional tidal streams. Hence a tidal stream power unit with counter-rotating type horizontal-axis bidirectional propellers is proposed in this paper. The blades with fully-symmetrical hydrofoils were optimized numerically. The output and flow conditions predicted by the computational fluid dynamics simulations are compared with the results of the wind tunnel experiments at the higher tip speed ratios, which are of expected usual operating conditions of this unit. The numerical and experimental results show good agreements. It is also confirmed that the flow discharged from the counter-rotating type propellers has no swirling component, though the single propeller generates the unacceptable swirling component. 展开更多
关键词 BIDIRECTIONAL PROPELLERS COUNTER-ROTATING type Machine TIDAL STREAM Power unit Computational Fluid Dynamics
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Social determinants of type 2 diabetes and health in the United States
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作者 Myra L Clark Sharon W Utz 《World Journal of Diabetes》 SCIE CAS 2014年第3期296-304,共9页
Diabetes is the sixth leading cause of death in the United States. To date, most research and resulting clinical strategies have focused on the individual with shortterm health improvements that have not been maintain... Diabetes is the sixth leading cause of death in the United States. To date, most research and resulting clinical strategies have focused on the individual with shortterm health improvements that have not been maintained over time. Researchers more recently have recognized the need to consider the social determinants of diabetes and health along with individual factors. The purpose of this literature review is to examine current understanding of the social determinants affecting diabetes and health. A search of medical and nursing literature was conducted using PubMed, PsychInfo, CINAHL and MEDLINE databases, selecting articles published between 2000 and 2013. Search terms included: type 2 diabetes, social determinants, and health determinants. Inclusion criteria were: English language, human studies, social determinants of diabetes and health, and research in the United States. Additional search methods included reference chaining of the literature. Twenty research articles met the inclusion criteria for the review and analysis and included quantitative and qualitative methods. All studies selected for this review were descriptive in nature(n = 20). Fifteen studies were quantitative studies and five were qualitative studies. No intervention studies met inclusion criteria. Each study is summarized and critiqued. Study findings indicate that external or upstream factors consistentlyaffect individuals diagnosed with diabetes, influencing self-management. Significant methodological limitations result directly from small sample sizes, convenience or nonprobability sampling, and low statistical power. 展开更多
关键词 type 2 DIABETES SOCIAL determinants HEALTH determinants Research unitED STATES
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A Remark on Pl Type Interpolation on Non-Uniformly Distributed Nodes on the Unit Circle
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作者 Neha Mathur P.Mathur 《Analysis in Theory and Applications》 2014年第2期173-192,共20页
In this paper we study the problem of explicit representation and convergence of Pal type (0;1) interpolation and its converse, with some additional conditions, on the non-uniformly distributed nodes on the unit cir... In this paper we study the problem of explicit representation and convergence of Pal type (0;1) interpolation and its converse, with some additional conditions, on the non-uniformly distributed nodes on the unit circle obtaIned by projecting the interlaced zeros of Pn (x) and Pn′ (x) on the unit circle. The motivation to this problem can be traced to the recent studies on the regularity of Birkhoff interpolation and Pal type interpolations on non-uniformly distributed zeros on the unit circle. 展开更多
关键词 Pal type interpolation non-uniformly distributed set of points on unit circle Legendre polynomials.
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Effect of Linear and Ring-like Co-units on the Temperature Dependence of Nucleation and Growth in Ⅱ-Ⅰ Phase Transition of Butene-1 Copolymers 被引量:3
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作者 Ya-Hui Lou Yi-Long Liao +3 位作者 Li Pan Bin Wang Yue-Sheng Li Zhe Ma 《Chinese Journal of Polymer Science》 SCIE CAS CSCD 2018年第11期1269-1276,共8页
The phase transition from tetragonal form II to hexagonal form I was studied for the butene-1/ethylene and butene-1/1,5- hexadiene random copolymers, which have comparable molecular weight but distinct linear ethylene... The phase transition from tetragonal form II to hexagonal form I was studied for the butene-1/ethylene and butene-1/1,5- hexadiene random copolymers, which have comparable molecular weight but distinct linear ethylene and ringlike methylene-1,3- cyclopentane (MCP) structural co-units, respectively. It is known that this solid phase transition follows the nucleation-growth mechanism, so the stepwise annealing protocol was utilized to investigate the influences of co-units on the optimal nucleation and growth temperatures. Compared with optimal nucleation and growth temperatures of-10 and 3 5 ℃, respectively, in polybutene-1 homopolymer, two butene-1/ethylene copolymers with 1.5 mol% and 4.3 mol% co-units have the slightly lower optimal nucleation temperature of-15 ℃ but much higher optimal growth temperature of 50 ℃. Clearly, the effect of ethylene co-unit is more significant on varying optimal temperature for growth than for nucleation. Furthermore, when the incorporated co-unit is ringlike MCP, the optimal nucleation temperature is -15 ℃ for 2.15 mol% co-units, the same with above BE copolymers, but -13 ℃ for a very low concentration of 0.65 mol%. Interestingly, the optimal growth temperature of butene-1/1,5-hexadiene copolymers with 0.65 mo1%-2.15 mol% MCP co- units increases to 55 ℃, which is also independent on co-unit concentration. These obtained values of optimal temperatures provide crucial parameters for rapid II-I phase transition. 展开更多
关键词 Butene-1 copolymer Co-unit type Phase transformation Nucleation Crystal growth
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Research on Design, Processing and Installation Technology of Unit Curtain Wall
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作者 HUANGMin 《外文科技期刊数据库(文摘版)工程技术》 2022年第8期181-184,共4页
During the construction process, the design and installation of curtain wall attach great importance to safety and sustainable applicability, which are widely used in buildings, which will also have a serious impact o... During the construction process, the design and installation of curtain wall attach great importance to safety and sustainable applicability, which are widely used in buildings, which will also have a serious impact on the expected benefits of future construction projects. Therefore, we must fully study and prepare the quality research of curtain wall construction technology, and start the construction on the basis of knowing the installation environment and infrastructure in detail. Otherwise, the actual mistakes in the process will lead to serious safety accidents, which is the concrete experience summarized in the actual operation. Based on this, this paper analyzes the design, processing and installation technology of unit curtain wall in detail. 展开更多
关键词 unit type curtain wall design PROCESSING installation technology
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塔架型抽油机预制分体式基础设计
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作者 刘长春 《油气田地面工程》 2026年第1期74-78,共5页
塔架型抽油机在采油工程领域中的应用日益广泛,为配合其推广应用,基础设计应以实现工厂化预制、现场装配化施工为出发点,满足地基承载力、变形及对基础振动控制的要求,并应具备后期油井维修时基础地面以上部分可反复拆装的功能。根据塔... 塔架型抽油机在采油工程领域中的应用日益广泛,为配合其推广应用,基础设计应以实现工厂化预制、现场装配化施工为出发点,满足地基承载力、变形及对基础振动控制的要求,并应具备后期油井维修时基础地面以上部分可反复拆装的功能。根据塔架型抽油机的运行特点、荷载特征及对基础的技术要求,通过对塔架型抽油机基础型式的对比分析,以及对基础荷载类型、基础底面积计算方法、基础结构设计方法、基础连接计算及构造做法等方面的研究,总结出了主要设计思路,明确了塔架型抽油机基础的设计要点,解决了预制化生产、装配化施工及后期拆装的问题。塔架型抽油机采用分体预制式基础,在实现基本功能的前提下,减少了现场施工工作量,缩短了施工周期,便于后期维修时拆装。设计方法已在实际工程项目中应用,并得到了进一步的优化,总结出的设计思路及设计要点对未来塔架型及游梁型抽油机基础设计具有一定的参考意义。 展开更多
关键词 塔架抽油机 分体箱形基础 动力荷载 等效静力法 刚性法
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On the Unit of Translation
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作者 张曼 《海外英语》 2013年第11X期176-177,182,共3页
The unit of translation has been the focus of debate through the history of translation. Barkhudarov suggests six levels of UT, each level could serve as unit of different levels of translation. Many Chinese translato... The unit of translation has been the focus of debate through the history of translation. Barkhudarov suggests six levels of UT, each level could serve as unit of different levels of translation. Many Chinese translators also expressed their opinions on this issue, but there is no settled answer yet. This paper tends to make a distinction between different texts: ordinary and special. Ordinary ones can adopt the UT of paragraph, while special ones should adopt special UTs according to their own characteristics. 展开更多
关键词 unit of TRANSLATION (UT) ordinary typeS of TEXTS s
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基于纵轴流开式玉米脱粒装置的优化设计与试验 被引量:3
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作者 张红梅 胡经营 +5 位作者 何勋 屈哲 杨立权 李世龙 刘冰杰 张静 《河南农业大学学报》 北大核心 2025年第1期122-135,共14页
【目的】解决现阶段玉米籽粒收获过程中籽粒破碎率和未脱净率高的问题,满足黄淮海地区玉米籽粒收获的要求。【方法】设计了纵轴流开式玉米脱粒装置,搭配钉齿式脱粒元件,将其按螺旋等间距排列的方式分布在辐条上。通过EDEM软件对脱粒装... 【目的】解决现阶段玉米籽粒收获过程中籽粒破碎率和未脱净率高的问题,满足黄淮海地区玉米籽粒收获的要求。【方法】设计了纵轴流开式玉米脱粒装置,搭配钉齿式脱粒元件,将其按螺旋等间距排列的方式分布在辐条上。通过EDEM软件对脱粒装置进行仿真分析,确定较佳的滚筒转速参数。以滚筒转速、喂入量、含水率为试验因素对脱粒装置进行单因素试验,得到较优的参数组合:滚筒转速为350.00 r⋅min^(-1)、喂入量为8.00 kg⋅s^(-1)、含水率为25.90%±1%。【结果】正交试验确定了影响的主次因素,先后依次为含水率、滚筒转速、喂入量。当滚筒转速为400 r⋅min^(-1)、喂入量为8.66 kg⋅s^(-1)、含水率为15.90%时,破碎率为3.99%、未脱净率为0.39%,脱粒装置台架验证试验得出该参数组合下破碎率和未脱净率分别为4.27%和0.51%,其中破碎率与理论优化值相差0.28%、未脱净率与理论优化值相差0.12%,试验结果与理论优化值非常接近。【结论】符合国家玉米籽粒直收的标准要求,为玉米籽粒收获机的研制提供了理论依据和新的研究思路。 展开更多
关键词 玉米脱粒 开式 脱粒装置 钉齿结构
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Specific primers design based on the superoxide dismutase b gene for Trypanosoma cruzi as a screening tool:Validation method using strains from Colombia classified according to their discrete typing unit
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作者 Francisco Olmo Javier Escobedo-Ortegón +4 位作者 Patricia Palma Manuel Sánchez-Moreno Ana Mejía-Jaramillo Omar Triana Clotilde Marín 《Asian Pacific Journal of Tropical Medicine》 SCIE CAS 2014年第11期854-859,共6页
Objective:To classify 21 new isolates of Trypanosoma cruai(T.cruzi) according to the Discrete Typing Unit(DTU) which they belong to,as well as tune up a new pair of primers designed to detect the parasite in biologica... Objective:To classify 21 new isolates of Trypanosoma cruai(T.cruzi) according to the Discrete Typing Unit(DTU) which they belong to,as well as tune up a new pair of primers designed to detect the parasite in biological samples.Methods:Strains were isolated,DNA extracted,and classified by using three Polymerase Chain Reactions(PCR).Subsequently this DNA was used along with other isolates of various biological samples,for a new PCR using primers designed.Finally,the amplified fragments were sequenced.Results:It was observed the predominance of DTU i in Colombia,as well as the specificity of our primers for detection of T.cruzi,while no band was obtained when other species were used.Conclusions:This work reveals the genetic variability of 21 new isolates of T.cruzi in Colombia.Our primers confirmed their specificity for detecting the presence of T.cruzi. 展开更多
关键词 TRYPANOSOMA CRUZI Polymerase chain reaction Colombia Superoxide dismutase GENE b-based primers DISCRETE TYPING unit
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Insulin Glargine 300 Units/mL Effectiveness in Patients with T2DM Uncontrolled by Basal Insulin in Real-Life Settings in the Czech Republic
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作者 Martin Prázný Milan Flekač +1 位作者 Petr Jelínek Jana Mašková 《Journal of Diabetes Mellitus》 2020年第3期109-123,共15页
<strong>Introduction:</strong><span><span><span style="font-family:;" "=""><span style="font-family:Verdana;"> To evaluate the clinical effectiven... <strong>Introduction:</strong><span><span><span style="font-family:;" "=""><span style="font-family:Verdana;"> To evaluate the clinical effectiveness of Gla-300 units/mL (Gla-300) in the treatment of patients with type 2 diabetes (T2DM) uncontrolled by basal insulin in real-life clinical settings in the Czech Republic (TOPAZ study). </span><b><span style="font-family:Verdana;">Methods:</span></b><span style="font-family:Verdana;"> TOPAZ was a prospective, multi-center, non-interventional, 6-month study. Of the 312 patients screened, 289 were evaluated at month 6. The primary objective was the change of HbA1c after 6 months. The proportion of patients with HbA1c < 7.0% DCCT (< 53 mmol/mol), and those with a decrease of at least 0.5% of HbA1c at month 6, change in FPG, body weight and insulin dose at month 3 and 6 were analysed as secondary objectives. Incidence of hypoglycemia, adverse events and patient treatment satisfaction were also assessed. </span><b><span style="font-family:Verdana;">Results:</span></b><span style="font-family:Verdana;"> HbA1c decreased significantly after 6 months (mean change 0.9% ± 1.1% DCCT [</span></span></span></span><span><span><span style="font-family:;" "=""><span style="font-family:Verdana;">&minus;</span><span style="font-family:Verdana;">9.9 ± 11.6 mmol/mol], p < 0.0001). HbA1c target < 7.0% DCCT was achieved in 17.6% of patients, 66.1% of patients showed mean HbA1c decrease of 0.5% ± 0.8%. At month 6, FPG decreased (mean change from baseline </span><span style="font-family:Verdana;">&minus;</span><span style="font-family:Verdana;">1.8 ± 3.1 mmol/L) as well as the incidence of hypoglycemia decreased by 49% (p <</span></span></span></span><span style="font-family:Verdana;"><span style="font-family:Verdana;"><span style="font-family:Verdana;"> 0.0001) while no weight gain was observed. No significant safety signals were ident</span></span></span><span><span><span style="font-family:;" "=""><span style="font-family:Verdana;">ified. </span><b><span style="font-family:Verdana;">Conclusion:</span></b><span style="font-family:Verdana;"> In a real-life setting, switching to Gla-300 in T2DM patients uncontrolled with other basal insulin was associated with improved glycemic control and reduced risk of hypoglycemia without weight gain, while patients’ satisfaction with treatment increased.</span></span></span></span> 展开更多
关键词 Fasting Plasma Glucose Glycated Hemoglobin HYPOGLYCEMIA Insulin Glargine (Gla-300 units/Ml) Real Life Data type 2 Diabetes (T2DM)
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储量评估单元划分在缝洞型碳酸盐岩PD储量评估中的应用实践——以哈拉哈塘油田为例
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作者 薛江龙 刘应飞 +2 位作者 张键 宋静波 罗俊成 《深地能源科技》 2025年第2期75-81,共7页
目前缝洞型碳酸盐岩油藏PD储量评估主要以开发单元或者油气田为评估单元进行上市储量评估,评估方法通常采用递减法。由于缝洞型碳酸盐岩储层非均质性极强、连通性差、油气分布复杂和天然能量不足的特征,钻遇不同储层类型及不同断裂带类... 目前缝洞型碳酸盐岩油藏PD储量评估主要以开发单元或者油气田为评估单元进行上市储量评估,评估方法通常采用递减法。由于缝洞型碳酸盐岩储层非均质性极强、连通性差、油气分布复杂和天然能量不足的特征,钻遇不同储层类型及不同断裂带类型上单井的递减规律、产能差异性明显;后期需要人工补能开发,开发方式影响导致递减规律性不强,油藏产能波动大,评估合理初始点和递减率取值难度大。根据上市储量评估保守原则,综合调整阶段,评估单元划分过大导致递减率取值偏大,初始值取值偏低,造成当前储量评估结果与开发形势存在一定的矛盾,油气田或者开发单元储采比偏低,不能反映出油藏真实开发规律。针对这一问题,在突出断裂性质、储层特征、开发方式、水体能量及经济性等因素基础上,提出储量评估单元划分技术思路。首先精细划分油藏单元,然后重构相似特征油藏单元组合成不同评估单元进行上市储量评估,再结合其开发规律选择合理的初始点和递减率对不同评估单元上市储量进行评估,靠实缝洞型碳酸盐岩油藏上市储量。研究结果表明:以哈拉哈塘为例,储量评估单元优化前,PD储量为115.55×10^(4)t,储采比为3.03;优化后,PD储量为175.69×10^(4)t,储采比为4.59。优化后精细评估的产量预测结果更能反映出哈拉哈塘油田缝洞型碳酸盐岩油藏真实开发规律,与实际产量变化趋势更吻合,储量评估结果与储采比也更靠实。该方法将用来指导缝洞型碳酸盐岩油藏PD储量评估。 展开更多
关键词 储量评估单元划分 缝洞型碳酸盐岩 PD储量 储采比
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统一战线与新型生产关系建构:四维交互机制审视
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作者 龚万达 《上海市社会主义学院学报》 2025年第5期70-84,共15页
以马克思主义理论指导下的社会资本理论、政府过程理论和制度变迁理论作为理论基础,提出统一战线通过“关系网络—制度生成—权力重构—价值传导”推动新型生产关系形成与发展的四维交互机制。统一战线在新型生产关系建构的启动、扩散... 以马克思主义理论指导下的社会资本理论、政府过程理论和制度变迁理论作为理论基础,提出统一战线通过“关系网络—制度生成—权力重构—价值传导”推动新型生产关系形成与发展的四维交互机制。统一战线在新型生产关系建构的启动、扩散、定型和风险控制阶段,分别发挥着创新触发、制度磨合、系统整合和负反馈调节的功能。通过激活社会资本、优化政府过程、推动制度变迁和重塑价值共识,统一战线形成了制度创新的“安全实验区”,解释了改革稳定性之谜,拓展了制度变迁理论的行动者网络,重构了政府过程理论的价值传导机制,进而促进了新型生产关系的建构。这为理解形成与新质生产力相适应的新型生产关系提供了新路径。 展开更多
关键词 统一战线 新质生产力 新型生产关系
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分体式空调器室内机底座模具设计
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作者 李凌华 《中国塑料》 北大核心 2025年第11期131-136,共6页
分析了分体式空调器室内机底座的结构,设计了一套在定模与动模都设置了顶出机构的注塑模具。为了使定模方向的、又长又高的筋位脱模,并为了克服开模时形成的真空,设计了定模顶出机构;对于产品外侧的筋位与底壁,设计了由斜导柱驱动的滑... 分析了分体式空调器室内机底座的结构,设计了一套在定模与动模都设置了顶出机构的注塑模具。为了使定模方向的、又长又高的筋位脱模,并为了克服开模时形成的真空,设计了定模顶出机构;对于产品外侧的筋位与底壁,设计了由斜导柱驱动的滑块机构;对于底壁上的扣位,设计了由双斜面斜楔驱动的滑块机构;对于通风口上方的V形槽,以及下方的3个扣位,共用一个滑块机构脱模;对于产品右上角的小圆柱孔和左右两侧的出水管,由于倾斜角度较大,分别设计了不同结构的斜抽芯机构;对于位于通风口中间的筋位,设计斜顶结构;为了保证注塑质量,采用热流道进行浇注,并将浇口位置的侧壁设置成圆柱形。为了保证模温均匀,根据模具结构设计随形冷却水路。 展开更多
关键词 空调器室内机底座 塑料模具 热流道 定模顶出机构 脱模机构
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考虑机组运行动态的热电厂电-热负荷实时优化分配 被引量:1
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作者 苏子航 吕泉 +4 位作者 陈筑 陈沪航 李佳丽 章艳 袁铁江 《中国电机工程学报》 北大核心 2025年第16期6426-6436,I0023,共12页
现有的厂级负荷分配研究忽视实时调度下由于供热机组可行域和煤耗特性动态变化所导致的分配结果偏离最优解甚至无法执行的问题。为此,该文以北方地区具有多类型供热机组的热电厂为对象,提出了考虑机组运行动态的热电厂电-热负荷实时优... 现有的厂级负荷分配研究忽视实时调度下由于供热机组可行域和煤耗特性动态变化所导致的分配结果偏离最优解甚至无法执行的问题。为此,该文以北方地区具有多类型供热机组的热电厂为对象,提出了考虑机组运行动态的热电厂电-热负荷实时优化分配模型。为计入机组实时运行时参数动态变化对耗量特性的影响,对于抽凝机组在传统二次煤耗特性函数中引入耗差系数进行修正,对于背压机组则考虑电热比受循环水流量和回水温度变化影响而动态变化导致二次煤耗特性函数无法适用,采用基于燃料利用效率的耗量特性模型。为计入机组实时运行时参数动态变化对可行运行域的影响,考虑配煤掺烧热值、热网加热器换热能力以及机组运行参数限值等参数对机组可行域边界以及抽凝机组中抽汽对发电影响因子和背压机组中的电热比两个关键参数进行实时修正,保证分配结果的可行性。基于东北地区某热电厂的算例分析验证所提实时负荷分配时计入机组运行动态的必要性及该文模型的有效性。 展开更多
关键词 运行动态 多类型供热机组 耗量特性 可行运行域 实时负荷分配
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苍山植被分类系统及特点 被引量:1
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作者 武力 李园园 +7 位作者 李孙玲 袁春明 司马永康 冯源 李甜江 柴勇 赵灿军 焦志伟 《西部林业科学》 北大核心 2025年第4期9-16,共8页
苍山地处横断山脉与滇中高原交汇地带,不同植被类型在该区域的交流与融合,极大地丰富了该区域的植物多样性和植被多样性,形成了极其典型且完整的山地植被生态系统。本文以247个植被样地资料为基础,依据《云南植被》的分类原则建立苍山... 苍山地处横断山脉与滇中高原交汇地带,不同植被类型在该区域的交流与融合,极大地丰富了该区域的植物多样性和植被多样性,形成了极其典型且完整的山地植被生态系统。本文以247个植被样地资料为基础,依据《云南植被》的分类原则建立苍山植被分类系统。结果显示:苍山植被划分为10个植被型、20个植被亚型、79个群系(森林群系28个,灌丛群系34个,草地群系6个,草甸群系6个,竹林群系1个,水生植被群系4个)和131个群落。其中,半湿润常绿阔叶林、中山湿性常绿阔叶林、山顶苔藓矮林、寒温山地硬叶常绿栎林、落叶阔叶林、暖温性针叶林、寒温性针叶林、寒温性灌丛等。是构成苍山植被景观的主体,也是维持区域生态系统稳定最重要的植被类型。苍山植被分类系统的建立对区域生物多样性保护、生态系统功能维护及山地植被研究具有重要科学价值。 展开更多
关键词 苍山 植被分类 分类单位 重要植被类型
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面向复杂电子设备的数字孪生车间应用探索
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作者 漆中华 金涛 +2 位作者 杜小东 郑联语 关迪 《电子产品可靠性与环境试验》 2025年第4期89-97,共9页
针对复杂电子设备生产工艺流程复杂、周期长、质量要求高,目前生产过程存在对高水平技能人才依赖程度高、数字化水平低、基于经验的决策不透明,以及外部需求产能动态变化等问题,提出了一种复杂电子设备数字孪生车间建设总体框架,建设了... 针对复杂电子设备生产工艺流程复杂、周期长、质量要求高,目前生产过程存在对高水平技能人才依赖程度高、数字化水平低、基于经验的决策不透明,以及外部需求产能动态变化等问题,提出了一种复杂电子设备数字孪生车间建设总体框架,建设了包括基于单元式生产方式及数字化工位的物理车间、建立与物理车间虚实同步映射的虚拟车间。采集包括数字化工位和业务信息系统生产数据,并对其进行挖掘应用,包括产线实时运行监控分析、车间运行分析与优化服务等,提高了复杂电子设备生产车间的数字化水平和柔性程度,提升了生产车间基于数据的智能化决策水平。 展开更多
关键词 数字孪生车间 数字化工位 单元式生产 虚拟现实辅助装配 智能化决策
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