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基于无人机的支挡结构三维重建及全场位移监测
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作者 朱前坤 周叙霖 杜永峰 《工程力学》 北大核心 2026年第1期230-239,共10页
支挡结构的位移监测可以为评估其工作状态、病害检测、灾害预警提供分析依据。为解决传统方法监测效率低、成本较高、危险系数大等缺点,该文提出基于无人机的支挡结构三维重建及全场位移监测方法。采用无人机拍摄支挡结构表面多视角图像... 支挡结构的位移监测可以为评估其工作状态、病害检测、灾害预警提供分析依据。为解决传统方法监测效率低、成本较高、危险系数大等缺点,该文提出基于无人机的支挡结构三维重建及全场位移监测方法。采用无人机拍摄支挡结构表面多视角图像,利用Colmap算法计算每张照片所对应的位姿并计算三维稀疏点云;利用基于深度学习的Patchmatchnet算法进行三维稠密点云重建;将不同时期的两期点云配准后利用M3C2算法进行点云对比,获得支挡结构的全场位移数据及位移云图。为验证该方法的准确性,在验证试验中应用了基于物理的图形模型(Physics-Based Graphical Model,PBGM),建立目标结构的Abaqus有限元模型,在有限元模型中施加荷载,计算模型的响应;将得到的变形后模型与未变形模型导出至Blender虚拟空间中,进行纹理贴图后设置无人机飞行航线,将3种工况下由该方法计算得到的全场位移与有限元计算得到的位移进行对比,验证了该方法在PBGM模型试验中,模型长度、宽度及位移监测方向上的误差均小于1 cm。在工程应用方面,将该方法应用于兰州市某框架复合锚杆土钉墙,成功监测到了其全场位移,证明该方法适用于人员不易到达、较为陡峭、危险性较高的支挡结构位移监测,可为支挡结构的安全性和稳定性评估提供依据。 展开更多
关键词 深度学习 位移监测 PBGM 三维重建 支挡结构 M3C2
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Effect of Berberine Chloride on Experimental Murine Colitis Induced by Dextran Sulfate Sodium 被引量:4
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作者 舒德忠 万先惠 +2 位作者 刘华蓉 杨俊卿 周岐新 《Journal of Chinese Pharmaceutical Sciences》 CAS 2006年第3期182-187,共6页
Aim To investigate the effect in berberine chloride (BER) on experimental ulcerative colitis in mice. Methods BALB/C mice in 6 groups were allowed to drink either 4% dextran sulfate sodium (DSS) solution or distil... Aim To investigate the effect in berberine chloride (BER) on experimental ulcerative colitis in mice. Methods BALB/C mice in 6 groups were allowed to drink either 4% dextran sulfate sodium (DSS) solution or distilled water freely with different doses of BER (15 mg·kg^-1, 45 mg·kg^-1, 150 mg·kg^-1) or sallcylazosulfapyridine (SASP, 520 mg·kg^-1), and solvent (0. 2 mL/10 mg Wt) once a day for 7 d, respectively. The symptom of ulcerative colitis was evaluated by disease activity index (DAI). Myeloperoxidase (MPO) and superoxide dismutase (SOD) activities and malondialdehyde (MDA) content were determined by HE staining and immunohistochemistry of expressions of NF-κB p65 and intercellular adhesion molecule 1 ( ICAM-1 ) proteins to observe the damage to colon tissues and possible mechanisms. Results DAI, MPO activity, MDA content and expressions of ICAM-1 and NF-κB p65 were markedly increased, while SOD activity decreased in DSS-treated mice. Treatment of mice with different doses of BER or SASP significantly decreased DAI, MPO activity and MDA content, improved histological changes of colon tissues, blunted the expressions of NF-κB p65 and ICAM-1 proteins, and enhanced SOD activity. Conclusion Berberine chloride has excellent therapeutic effect on ulcerative colitis caused by DSS in mice. The possible mechanism may be related to its antioxidant and anti-inflammatory activities associated with inhibiting the NF-κB activation and ICAM-1 expression. 展开更多
关键词 berberine chloride ulcerative colitis dextran sulfate sodium BALB/C mice
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Enhanced photocatalytic Cr(Ⅵ) reduction and diclofenac sodium degradation under simulated sunlight irradiation over MIL-100(Fe)/g-C_3N_4 heterojunctions 被引量:20
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作者 Xuedong Du Xiaohong Yi +2 位作者 Peng Wang Jiguang Deng Chong‐chen Wang 《Chinese Journal of Catalysis》 SCIE EI CAS CSCD 北大核心 2019年第1期70-79,共10页
Metal‐organic framework MIL‐100(Fe)and g‐C3N4 heterojunctions(MG‐x,x=5%,10%,20%,and 30%,x is the mass fraction of MIL‐100(Fe)in the hybrids)were facilely fabricated through ball‐milling and annealing,and charact... Metal‐organic framework MIL‐100(Fe)and g‐C3N4 heterojunctions(MG‐x,x=5%,10%,20%,and 30%,x is the mass fraction of MIL‐100(Fe)in the hybrids)were facilely fabricated through ball‐milling and annealing,and characterized by powder X‐ray diffraction,Fourier transform infrared spectroscopy,thermogravimetric analysis,transmission electron microscopy,UV‐visible diffuse‐reflectance spectrometry,and photoluminescence emission spectrometry.The photocatalytic activities of the series of MG‐x heterojunctions toward Cr(VI)reduction and diclofenac sodium degradation were tested upon irradiation with simulated sunlight.The influence of different organic compounds(ethanol,citric acid,oxalic acid,and diclofenac sodium)as hole scavengers and the pH values(2,3,4,6,and 8)on the photocatalytic activities of the series of MG‐x heterojunctions was investigated.MG‐20%showed superior photocatalytic Cr(VI)reduction and diclofenac sodium degradation performance than did the individual MIL‐100(Fe)and g‐C3N4 because of the improved separation of photoinduced electron‐hole charges,which was clarified via photoluminescence emission and electrochemical data.Moreover,the MG‐x exhibited good reusability and stability after several runs. 展开更多
关键词 MIL‐100(Fe) g‐C3N4 HETEROJUNCTION Cr(VI)reduction Diclofenac sodium
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Changes of c-fos and c-jun mRNA Expression in Angiotensin Ⅱ-induced Cardiomyocyte Hypertrophy and Effects of Sodium Tanshinone ⅡA Sulfonate 被引量:9
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作者 周代星 梁黔生 +1 位作者 何雪心 占成业 《Journal of Huazhong University of Science and Technology(Medical Sciences)》 SCIE CAS 2008年第5期531-534,共4页
The changes of proto-oncogene c-fos and c-jun mRNA expression in angiotensin Ⅱ (AngⅡ)-induced hypertrophy and effects of sodium tanshinone ⅡA sulfonate (STS) in the primary culture of neonatal rat cardiomyocyte... The changes of proto-oncogene c-fos and c-jun mRNA expression in angiotensin Ⅱ (AngⅡ)-induced hypertrophy and effects of sodium tanshinone ⅡA sulfonate (STS) in the primary culture of neonatal rat cardiomyocytes were investigated. Twelve neonatal clean grade Wistar rats were selected. The cardiomyocytes were isolated, cultured and divided according to different treatments in the medium. The cardiomyocyte size was determined by phase contrast microscope, and the rate of protein synthesis was measured by [3H]-Leucine incorporation. The c-fos and c-jun mRNA expression in cardiomyocytes was detected by reverse transcription polymerase chain reaction (RT-PCR). It was found after cardiomyocytes were treated with AngⅡ for 30 min, the c-fos and c-jun mRNA expression in cardiomyocytes was increased significantly (P〈0.01). After treatment with AngⅡ for 24 h, the rate of protein synthesis in AngⅡ group was significantly increased as compared with control group (P〈0.01). After treatment with AngⅡ for 7 days, the size of cardiomyocytes in AngⅡ group was increased obviously as compared with control group (P〈0.05). After pretreatment with STS or Valsartan before AngⅡ treatment, both of them could inhibit the above effects of AngⅡ (P〈0.05 or P〈0.01). It was suggested that STS could ameliorate AngⅡ-induced cardiomyocyte hy- pertrophy by inhibiting c-fos and c-jun mRNA expression and reducing protein synthesis rate of cardiomyocytes. 展开更多
关键词 sodium tanshinone A sulfonate angiotensin cardiomyocyte hypertrophy C-LOS C-JUN
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SnS_2@C Hollow Nanospheres with Robust Structural Stability as High?Performance Anodes for Sodium Ion Batteries 被引量:10
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作者 Shuaihui Li Zhipeng Zhao +2 位作者 Chuanqi Li Zhongyi Liu Dan Li 《Nano-Micro Letters》 SCIE EI CAS CSCD 2019年第1期241-249,共9页
Constructing unique and highly stable structures with plenty of electroactive sites in sodium storage materials is a key factor for achieving improved electrochemical properties through favorable sodium ion di usion k... Constructing unique and highly stable structures with plenty of electroactive sites in sodium storage materials is a key factor for achieving improved electrochemical properties through favorable sodium ion di usion kinetics. An SnS_2@carbon hollow nanospheres(SnS_2@C) has been designed and fabricated via a facile solvothermal route, followed by an annealing treatment. The SnS_2@C hybrid possesses an ideal hollow structure, rich active sites, a large electrode/electrolyte interface, a shortened ion transport pathway, and, importantly, a bu er space for volume change, generated from the repeated insertion/extraction of sodium ions. These merits lead to the significant reinforcement of structural integrity during electrochemical reactions and the improvement in sodium storage properties, with a high specific reversible capacity of 626.8 mAh g^(-1) after 200 cycles at a current density of 0.2 A g^(-1) and superior high-rate performance(304.4 mAh g^(-1) at 5 A g^(-1)). 展开更多
关键词 SnS2@C HOLLOW NANOSPHERES ANODE materials sodium ion BATTERIES
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Atom-efficient coupling reaction of aryl bromides with sodium tetraphenylborate catalyzed by reusable Pd/C in water under focused microwave irradiation 被引量:1
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作者 Lin Bai 《Chinese Chemical Letters》 SCIE CAS CSCD 2009年第2期158-160,共3页
A rapid and heterogeneous Pd/C-catalyzed atom-efficient phenylation of aryl bromides by sodium tetraphenylborate takes place under focused microwave irradiation in water. The palladium catalyst can be easily recovered... A rapid and heterogeneous Pd/C-catalyzed atom-efficient phenylation of aryl bromides by sodium tetraphenylborate takes place under focused microwave irradiation in water. The palladium catalyst can be easily recovered and reused. 展开更多
关键词 PD/C sodium tetraphenylborate WATER Focused microwave irradiation
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Direct oxidation of methane at low temperature using Pt/C,Pd/C,Pt/C-ATO and Pd/C-ATO electrocatalysts prepared by sodium borohydride reduction process 被引量:1
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作者 J.Nandenha E.H.Fontes +2 位作者 R.M.Piasentin F.C.Fonseca A.O.Neto 《燃料化学学报》 EI CAS CSCD 北大核心 2018年第9期1137-1145,共9页
The main objective of this paper was to characterize the voltammetric profiles of the Pt/C,Pt/C-ATO,Pd/C and Pd/CATO electrocatalysts and study their catalytic activities for methane oxidation in an acidic electrolyte... The main objective of this paper was to characterize the voltammetric profiles of the Pt/C,Pt/C-ATO,Pd/C and Pd/CATO electrocatalysts and study their catalytic activities for methane oxidation in an acidic electrolyte at 25 ℃ and in a direct methane proton exchange membrane fuel cell at 80 ℃. The electrocatalysts prepared also were characterized by X-ray diffraction( XRD) and transmission electron microscopy( TEM). The diffractograms of the Pt/C and Pt/C-ATO electrocatalysts show four peaks associated with Pt face-centered cubic( fcc) structure,and the diffractograms of Pd/C and Pd/C-ATO show four peaks associated with Pd face-centered cubic( fcc) structure. For Pt/C-ATO and Pd/C-ATO,characteristic peaks of cassiterite( SnO_2) phase are observed,which are associated with Sb-doped SnO_2( ATO) used as supports for electrocatalysts. Cyclic voltammograms( CV) of all electrocatalysts after adsorption of methane show that there is a current increase during the anodic scan. However,this effect is more pronounced for Pt/C-ATO and Pd/C-ATO. This process is related to the oxidation of the adsorbed species through the bifunctional mechanism,where ATO provides oxygenated species for the oxidation of CO or HCO intermediates adsorbed in Pt or Pd sites. From in situ ATR-FTIR( Attenuated Total Reflectance-Fourier Transform Infrared) experiments for all electrocatalysts prepared the formation of HCO or CO intermediates are observed,which indicates the production of carbon dioxide. Polarization curves at 80 ℃in a direct methane fuel cell( DMEFC) show that Pd/C and Pt/C electroacatalysts have superior performance to Pd/C-ATO and Pt/C-ATO in methane oxidation. 展开更多
关键词 sodium BOROHYDRIDE reduction process Pt/C-ATO and Pd/C-ATO ELECTROCATALYSTS METHANE oxidation acidic electrolytes polarization curves
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涂布专用C.M.C在涂布加工纸中的应用与对比 被引量:1
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作者 马世芳 《湖北造纸》 1999年第4期19-21,共3页
羧甲基纤维素是一种纤维素的衍生物,在涂布纸与纸板的生产中它作为优良的保水剂,也可作为辅助胶粘剂。众所周知,涂布纸从涂布到干燥过程中不可避免地存在着胶粘剂的再分配问题——迁移现象。粘合剂迁移的结果对纸张的印刷效果有着至关... 羧甲基纤维素是一种纤维素的衍生物,在涂布纸与纸板的生产中它作为优良的保水剂,也可作为辅助胶粘剂。众所周知,涂布纸从涂布到干燥过程中不可避免地存在着胶粘剂的再分配问题——迁移现象。粘合剂迁移的结果对纸张的印刷效果有着至关重要的影响。CMC优良的保水性可有效地阻止胶粘剂不适当的迁移,改善纸张涂层对油墨的吸收性,避免印刷斑点,提高涂层强度。CMC所制涂料固含量高,流变性能好,在刮刀涂布中应用可减少刮刀条痕,提高涂布质量,有润滑刮刀的作用,延长刮刀的使用寿命,在气刀涂布中应用可提高车速、减少粘边。不同粘度规格、不同用量的CMC的应用,可在保证涂布适应性和涂布质量的前提下,灵活调整涂料粘度以适应生产的不同要求。 展开更多
关键词 加工纸 刮刀涂布 c.m.c 干强度 涂布质量 辅助胶粘剂 流变性能 对比试验 纸张光泽度 油墨吸收性
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Application of Sodium Ion Sensor Based on the SnO_2/ITO Glass in the Detection of Rinsing Solution for Contact Lenses
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作者 Jui-Fu Cheng Jung-Chuan Chou +1 位作者 Tai-Ping Sun Shen-Kan Hsiung 《稀有金属材料与工程》 SCIE EI CAS CSCD 北大核心 2006年第A03期240-241,共2页
This paper presents the studying results of the sodium ion sensor device based on the SnO_2/ITO glass structure in the detection of rinsing solution for contact lenses.The selective membrane contains poly (vinyl chlor... This paper presents the studying results of the sodium ion sensor device based on the SnO_2/ITO glass structure in the detection of rinsing solution for contact lenses.The selective membrane contains poly (vinyl chloride) (PVC),bis (2-ethylhexyl) sebacate (DOS),(12-crown-4) methylmalonate (B12C4),and sodium tetrakis (4-fluoropbenyl) borate dehydrate (NaTFBD). The final weight ratios are PVC:DOS:B12C4:NaTFBD=33:66:2:2.In this condition,the sensor has performances with linear sensitivity,short response time,good repeatability and selectivity.The sensor was used to measure the rinsing solution for the contact lenses.Because the experimental results show close to the accurate value for four commercial products,this sensor can preliminary be used in detecting the rinsing solution for the contact lenses.Using this structure and sodium-sensing membrane to construct the sodium sensor is proven successfully in this application. 展开更多
关键词 sodium ion sensor solution for contact lenses tin oxide electrode B12C4
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C.M.C在棒形支柱瓷绝缘子粘砂中的应用
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作者 刘双秋 《电瓷避雷器》 CAS 北大核心 2002年第3期13-14,共2页
分析了 1 0 7胶在棒形支柱瓷绝缘子粘砂过程中的缺点及 c.m.c的优点。采用 c.m.c替代 1 0 7胶做为粘砂结合剂后 ,解决了生产中产生的剥砂、落脏等问题 ,并降低了生产成本。
关键词 棒形支柱瓷绝缘子 粘砂 107胶 粘结剂 c.m.c
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STUDY ON ACRYLAMIDE-SODIUM ACRYLATE COPOLYMER GELS
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作者 周茂堂 李谦 徐纪平 《Chinese Journal of Polymer Science》 SCIE CAS CSCD 1990年第3期211-216,共6页
Acrylamide-sodium acrylate copolymer hydrogels have been obtained by radiation techniques. Two different methods have been used to introduce—COONa groups into polymer chains of the gels: (1) by partial hydrolysis of ... Acrylamide-sodium acrylate copolymer hydrogels have been obtained by radiation techniques. Two different methods have been used to introduce—COONa groups into polymer chains of the gels: (1) by partial hydrolysis of acrylamide homopolymer gel; (2) by direct copolymerization and crosslinking of acrylamide and sodium acrylate in aqueous solutions. It was found that the gels obtained in different ways had different properties, the swelling character of the gels obtained by partial hydrolysis were more sensitive to pH of swelling aqueous media, in order to explain these differences, ^(13)C-NMR techniques were used to investigate the sequence distribution of monomer units of both gels. 展开更多
关键词 ACRYLAMIDE sodium acrylate RADIATION HYDROGEL Water Retention Value ^(13)C-NMR
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Quantitative Structure-Activity Relationships in the Lithium and Sodium Affinities of n-Alkyl Fluorides
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作者 Ke Chun ZHANG Jian Miao FAN +1 位作者 Lei LIU Qing Xiang GUO 《Chinese Chemical Letters》 SCIE CAS CSCD 2002年第1期41-44,共4页
B3LYP/6-31+g (d, p) method was used to calculate the lithium and sodium affinities of n-alkyl fluoride. These affinities were found to obey the Holmes relationship, i.e. they correlate linearly with the quotient n/(n... B3LYP/6-31+g (d, p) method was used to calculate the lithium and sodium affinities of n-alkyl fluoride. These affinities were found to obey the Holmes relationship, i.e. they correlate linearly with the quotient n/(n+1), where n is the number of carbon atoms in the alkyl chain. From the correlation the limiting values of lithium and sodium affinities for very long alkyl chain were predicted to be 153.3 kJ/mol and 108.4 kJ/mol, respectively. 展开更多
关键词 Lithium affinity sodium affinity density functional theory C-F卪etal interaction ion attachment.
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生成式人工智能训练使用作品的许可复合机制研究 被引量:5
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作者 倪朱亮 《法律科学(西北政法大学学报)》 北大核心 2025年第4期90-103,共14页
合理使用制度无法完全规范生成式人工智能训练使用作品行为,需正视许可制度对增进作品效用的价值。在作品是模型训练成功的基础资源、使用多元化作品可避免大模型崩溃以及作者对作品的贡献等因素的考量下,确有通过许可制度补偿作者表达... 合理使用制度无法完全规范生成式人工智能训练使用作品行为,需正视许可制度对增进作品效用的价值。在作品是模型训练成功的基础资源、使用多元化作品可避免大模型崩溃以及作者对作品的贡献等因素的考量下,确有通过许可制度补偿作者表达成本的必要性。引入“卡一梅框架”可解决财产规则与作品需求高效性、责任规则与权利自治性之间的冲突,通过建立作品许可复合机制实现作品许可在成本与效率上的平衡。具体而言,责任规则下经法释义学解释的法定许可,可成为生成式人工智能训练使用作品的合法性基础。明确法定许可的临时安排性质和引入多元化许可费标准,可满足现阶段行业对使用作品的刚性需求。伴随生成式人工智能信息披露义务的法定化,许可机制遵循财产规则还需借助著作权集体管理组织。该路径既可以降低传统许可机制在实现收益上的成本,也可以解决因互联网全球性特征导致的单一法定许可无法覆盖全场景许可市场的难题。 展开更多
关键词 生成式人工智能 许可复合机制 卡一梅框架 法定许可 著作权集体管理组织
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Observation of the Curative Effect of Sodium Hyaluronate Combined with Fuming Capsule on Dry Eye after Cataract Operation
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作者 WU Xueyan CHEN Qiang 《外文科技期刊数据库(文摘版)医药卫生》 2021年第9期1215-1217,共5页
Objective: to analyze the curative effect of 0.1% sodium hyaluronate eye drops combined with Fuming capsule in the treatment of dry eye after cataract surgery. Methods: a total of 100 healthy express cataract patients... Objective: to analyze the curative effect of 0.1% sodium hyaluronate eye drops combined with Fuming capsule in the treatment of dry eye after cataract surgery. Methods: a total of 100 healthy express cataract patients with dry eye after cataract surgery were enrolled from September 2015 to November 2015, and randomly divided into two groups. Patients in the single drug group were given 0.1% sodium hyaluronate eye drops, while patients in the traditional Chinese and western medicine group were added with Fuming capsules on the basis of the single drug group. Compare the effects. Results: the symptom relief time of Chinese and western medicine group was shorter than that of single drug group, and the curative effect of dry eye was higher than that of single drug group, P<0.05. Conclusion: the application of 0.1% sodium hyaluronate eye drops and fuming capsule can effectively relieve xerophthalmia. 展开更多
关键词 observation 0.1% sodium hyaluronate eye drops fuming capsule dry eye after cataract surgery the c
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考虑行人结伴行为及通过能力的大型车站应急疏散模型
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作者 王炜 姚恩建 《铁道学报》 北大核心 2025年第5期22-30,共9页
大型车站作为人流和物流的集散中心,其应急疏散效率直接关系到公共安全。既有的应急疏散方法忽略了行人结伴行为对应急疏散效率的影响。针对此问题,将度量大型车站内通行设施通过能力的M/G/C/C模型与考虑行人结伴行为的社会力模型相结合... 大型车站作为人流和物流的集散中心,其应急疏散效率直接关系到公共安全。既有的应急疏散方法忽略了行人结伴行为对应急疏散效率的影响。针对此问题,将度量大型车站内通行设施通过能力的M/G/C/C模型与考虑行人结伴行为的社会力模型相结合,提出一种考虑行人结伴行为与设施通过能力的应急疏散模型,有效地辨识与分析轨道交通大型车站内局部行人应急疏散的疏散瓶颈点和疏散时间。以某大型车站站内换乘疏散通道为例,并与M/G/C/C模型对比分析。研究结果表明,行人结伴行为会影响应急疏散过程中行人行走速度和通行设施的最大容量,进而影响大型车站内应急疏散时的输出率、输出效率、拥堵概率、期望疏散人数、期望疏散时间、平均密度。 展开更多
关键词 应急疏散 行人结伴行为 M/G/C/C模型 疏散时间 疏散瓶颈
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镍、钴对超高强度船体钢组织与性能的影响
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作者 李健 刘浩 +1 位作者 罗小兵 柴锋 《钢铁研究学报》 北大核心 2025年第5期670-678,共9页
利用SEM、TEM、XRD和EBSD等技术系统研究了镍、钴元素对新型NiCrMoV系船体钢显微组织、第二相析出以及力学性能的影响。结果表明,经过淬火和回火工艺处理,试验钢显微组织均主要由回火马氏体和少量逆转变奥氏体组成,且在回火过程中主要... 利用SEM、TEM、XRD和EBSD等技术系统研究了镍、钴元素对新型NiCrMoV系船体钢显微组织、第二相析出以及力学性能的影响。结果表明,经过淬火和回火工艺处理,试验钢显微组织均主要由回火马氏体和少量逆转变奥氏体组成,且在回火过程中主要析出了富含Mo、Cr和V元素的细针状M2C型第二相。经过850℃淬火+580℃回火工艺,新型NiCrMoV钢屈服强度可达到1140MPa,-84℃低温冲击功达到76J。随着试验钢中Ni含量的增加,晶粒明显细化、大角度晶界增多、逆转变奥氏体增多,有效抑制了裂纹的形成与扩展,将钢的低温韧性水平提高到82J。试验钢中添加Co元素后,钢中位错密度增大,析出的M2C相增多且分布更为弥散,使试验钢达到了1216MPa的超高屈服强度。 展开更多
关键词 超高强船体钢 Ni Co 逆转变奥氏体 M2C相 强韧性
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集中管理模式下排队论M/M/C模型输入数据精度对监护仪配置数量预测准确性的影响
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作者 谢峰 王宇坤 +3 位作者 王晓龙 侯艺威 郭米嘉 白玫 《中国医疗设备》 2025年第4期97-101,150,共6页
目的研究集中管理模式下排队论M/M/C模型输入数据选取精度对监护仪合理配置数量预测准确性的影响。方法选取本院11个病区作为研究对象,提取医嘱时长作为监护仪实际使用时长,按照11个病区合并计算(组别1)、内外科分别合并计算(组别2)、... 目的研究集中管理模式下排队论M/M/C模型输入数据选取精度对监护仪合理配置数量预测准确性的影响。方法选取本院11个病区作为研究对象,提取医嘱时长作为监护仪实际使用时长,按照11个病区合并计算(组别1)、内外科分别合并计算(组别2)、各病区独立计算(组别3)设立对比组别,建立排队论M/M/C预测模型,结合护理要求和排队系统等待时长曲线推测监护仪配置数量预测区间,分别对比3个组别的预测区间与实际配置数量差异值。结果组别1模型预测差值最大(最大差值为7.84台,最小差值为2.45台),组别2模型预测差值次之(最大差值为6.73台,最小差值为2.27台),组别3模型预测差值最小(仅有4个病区存在差异,差值为1或3台)。3组差值之间的差异有统计学意义(H=20.768,P<0.001),组别3模型预测差值与组别1和2的模型预测差值相比均有统计学意义(P<0.001),组别1和2模型预测差值相比差异无统计学意义(P=0.465)。结论输入数据选取精度因素对排队论M/M/C模型预测准确性具有一定影响,各医疗机构在利用排队论模型测算配置数量时,应尽量提高数据选取精度,按最小病区单元选取输入数据,并在预测结果的基础上结合临床实际情况浮动实际配置数量,提升配置数量合理性。 展开更多
关键词 集中管理 数据选取精度 排队论 M/M/C模型 合理配置数量 监护仪 预测差异
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电商平台C2M模式的新质供给创新发展策略研究 被引量:1
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作者 王从辉 《安徽商贸职业技术学院学报》 2025年第2期13-18,共6页
电商平台C2M模式作为一种创新的生产和消费对接方式,与新质生产力在技术、制度、生态等维度有着较强的耦合协同关系。我国很多电商企业率先开展C2M实践探索并取得了一定成果,但在新质供给上还存在着技术、需求、生态和制度等方面的问题... 电商平台C2M模式作为一种创新的生产和消费对接方式,与新质生产力在技术、制度、生态等维度有着较强的耦合协同关系。我国很多电商企业率先开展C2M实践探索并取得了一定成果,但在新质供给上还存在着技术、需求、生态和制度等方面的问题有待破解。采取技术驱动型新质供给创新策略、需求导向型新质供给协同策略、生态协同型新质供给进化策略和制度创新型新质供给保障策略,可以为“工业互联网”时代的电子商务产业升级提供理论支持和实践指导。 展开更多
关键词 电商平台 C2M模式 新质供给 创新策略
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基于AnyLogic仿真的机场值机系统资源配置
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作者 唐卫贞 杨明明 +3 位作者 李俊 于千容 成昌浩 彭峻德 《计算机应用与软件》 北大核心 2025年第11期81-88,共8页
机场值机柜台数的决策主要考虑值机柜台成本和旅客时间成本两个方面。基于AnyLogic软件的社会力模型和面向对象技术,根据某机场进行仿真模型搭建,将求得的机场旅客到达及服务时间等参数导入模型进行仿真运行,将AnyLogic仿真运行得到的... 机场值机柜台数的决策主要考虑值机柜台成本和旅客时间成本两个方面。基于AnyLogic软件的社会力模型和面向对象技术,根据某机场进行仿真模型搭建,将求得的机场旅客到达及服务时间等参数导入模型进行仿真运行,将AnyLogic仿真运行得到的结果与改进的M/M/C模型计算得到的结果进行对比,仿真得到的平均排队长度和平均排队时间分别为3.192、4.763,与计算得到的2.954、4.982基本一致。研究表明用改进的M/M/C模型求解机场最优值机柜台数优化了机场决策过程,使用AnyLogic仿真验证了改进的M/M/C方法的可靠性,为机场值机资源配置提供了更优更可靠的求解验证方法。 展开更多
关键词 值机柜台 社会力模型 面向对象 AnyLogic仿真 改进的M/M/C模型
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陆上洪水型优质砂体形成机理——以兰州窑街地区炭洞沟二号坝洪水沉积为例
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作者 李相博 刘化清 +5 位作者 郝彬 杨占龙 张晶 刘震华 李智勇 李在光 《岩性油气藏》 北大核心 2025年第6期28-34,共7页
通过野外地质考察及实验分析测试,明确了兰州窑街地区炭洞沟泥石流多发地段的洪水沉积特征,并揭示了优质砂体的形成机理。研究结果表明:(1)兰州窑街地区炭洞沟洪水沉积物分为砂砾石(G)、含砾粗砂(C)、中细砂(MS)及含粉细砂泥质沉积(黏土... 通过野外地质考察及实验分析测试,明确了兰州窑街地区炭洞沟泥石流多发地段的洪水沉积特征,并揭示了优质砂体的形成机理。研究结果表明:(1)兰州窑街地区炭洞沟洪水沉积物分为砂砾石(G)、含砾粗砂(C)、中细砂(MS)及含粉细砂泥质沉积(黏土)(FM)4种类型,自上游向下游有序分布,中细砂(MS)在汇水区下游段连续分布,分选良好,为优质砂体。(2)研究区洪水沉积物的有序分布与流体搬运过程中泥石流(非牛顿流体)向牵引流(牛顿流体)转化有关,该转化受区域“V”形拐弯河道及地形坡度变化联合控制;牵引流的机械分异作用及高能洪水颗粒间的碰撞破碎是研究区优质砂体形成的主要原因。 展开更多
关键词 泥石流 牵引流 洪水事件 优质砂体 C-M图 现代沉积 陆相环境
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