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Law and Literature: Exploring the Intersection of Two Fields
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作者 HU Chun-xi 《Journal of Literature and Art Studies》 2023年第3期170-177,共8页
This article aims to explore the intersection of law and literature,analyzing their connections and influences.First,the article introduces the definitions and basic characteristics of law and literature,emphasizing t... This article aims to explore the intersection of law and literature,analyzing their connections and influences.First,the article introduces the definitions and basic characteristics of law and literature,emphasizing their similarities and differences.Then,the article discusses how literary works involve legal issues and how law becomes the subject and background of literary works.In addition,the article studies the interaction between law and literature,exploring the impact of novels on legal practice,and how legal texts are rewritten and interpreted in literary works.Finally,the article summarizes the relationship between law and literature and offers some prospects and reflections. 展开更多
关键词 LAW LITERATURE intersection INTERACTION influence
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An Influence Maximization Algorithm Based on the Influence Propagation Range of Nodes
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作者 Yong Hua Bolun Chen +2 位作者 Yan Yuan Guochang Zhu Fenfen Li 《Journal on Internet of Things》 2019年第2期77-88,共12页
The problem of influence maximization in the social network G is to find k seed nodes with the maximum influence.The seed set S has a wider range of influence in the social network G than other same-size node sets.The... The problem of influence maximization in the social network G is to find k seed nodes with the maximum influence.The seed set S has a wider range of influence in the social network G than other same-size node sets.The influence of a node is usually established by using the IC model(Independent Cascade model)with a considerable amount of Monte Carlo simulations used to approximate the influence of the node.In addition,an approximate effect(1􀀀1=e)is obtained,when the number of Monte Carlo simulations is 10000 and the probability of propagation is very small.In this paper,we analyze that the propagative range of influence of node set is limited in the IC model,and we find that the influence of node only spread to the t0-th neighbor.Therefore,we propose a greedy algorithm based on the improved IC model that we only consider the influence in the t0-th neighbor of node.Finally,we perform experiments on 10 real social network and achieve favorable results. 展开更多
关键词 influence maximization social network IC range
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Influence range of emergency under special events based on CTM 被引量:6
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作者 陈茜 李文权 《Journal of Southeast University(English Edition)》 EI CAS 2009年第2期257-261,共5页
To determine the dynamic influence range of emergencies under special events, the spacial and temporal characteristics of the traffic flow are studied by simulation based on the cell transmission model (CTM). Based ... To determine the dynamic influence range of emergencies under special events, the spacial and temporal characteristics of the traffic flow are studied by simulation based on the cell transmission model (CTM). Based on the traffic management measures used under special events, a semi-dynamic assignment algorithm is proposed, which is combined with an algorithm for logit multi-path traffic assignment and the CTM. In a simple calculation network, the spacial and temporal characteristics of traffic flows which vary with different traffic management schemes are studied, and a method to obtain the influence range of emergency is proposed by computing the jam time of the intersections. By contrasting the average delay of each vehicle, the dissipation effect is studied under two different traffic management schemes. The example shows that the spatial and temporal variety of the traffic flow can be easily simulated and the influence range of emergency can be confirmed by the method based on the CTM. The proposed method provides a new idea for decision-making on traffic management under emergency under special events. 展开更多
关键词 traffic management special event EMERGENCY influence range cell transmission model (CTM)
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The influence of head-neck and implant position on the range of motion after total hip arthroplasty
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作者 罗志平 《外科研究与新技术》 2005年第3期180-180,共1页
To study the influence of head-neck ratio and implant position on the range of motion (ROM) after total hip arthroplasty (THA).Methods In this study the author established a three-dimensional computerized model of hip... To study the influence of head-neck ratio and implant position on the range of motion (ROM) after total hip arthroplasty (THA).Methods In this study the author established a three-dimensional computerized model of hip joint and tested the range of motion of three different head-neck ratio after total hip arthroplasty.Results Range of motion after total hip arthroplasty depended on design parameters such as head-neck ratio,but also on the implantation parameters such as the cup’s inclination and antevertion,the stem’s antevertion and their combination of each other.Optimal range of motion required compliant position of total hip components.The range of motion increased with the enlarging of head-hnck ratio.Conclusion Higher head-neck ratio leads to optimal range of motion and decreased the prevalence of prosthetic impingement within compliant,well-defined combination of cup’s inclination,cup’s antevertion and stem’s antevertion depending on the intended ROM.Domestic magnesium-silicon jade total hip prosthesis has too low head-neck ratio to result in enough range of motion that fulfilled daily living after total hip arthroplasty.14 refs,4 figs,3 tabs. 展开更多
关键词 the influence of head-neck and implant position on the range of motion after total hip arthroplasty
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Factors Influencing Home Ranges of the Qinghai Toad-headed Lizard(Phrynocephalus vlangalii)on the Dangjin Mountain,Gansu
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作者 Xiaolong ZHAO Wei YU +2 位作者 Zeyu ZHU Yuxia YANG Zhigao ZENG 《Asian Herpetological Research》 SCIE CSCD 2022年第2期137-144,共8页
Home range is an important ecological parameter reflecting the suita bility of animal habitats.To study the size and factors influencing the home ranges of the Qinghai toad-headed lizard(Phr ynocephalus vlangalii)in d... Home range is an important ecological parameter reflecting the suita bility of animal habitats.To study the size and factors influencing the home ranges of the Qinghai toad-headed lizard(Phr ynocephalus vlangalii)in different habitats,from July to September 2020,we radio-tagged and tracked 15 individuals in each of sites distributed at high(3600 m)and low(2600 m)altitudes on the Dangjin Mountain,Gansu Province,northwest China.We calculated home range size using the 100%minimum convex polygon method,and analyzed the influence of inherent lizard characteristics and external environmental factors.Our results revealed that for both high-and lowaltitude lizard populations,the sizes of home ranges were positively correlated with lizard body mass.Moreover,after eliminating the effect of body mass as a covariable,we established that the home ranges of high-altitude lizards(5255.1±1103.8 m^(2))were larger than those of the low-altitude lizards(2208.1±348.7 m^(2)).Lizards in the high-altitude population were also characterized by longer daily suitable activity times and spent significantly more time in full sunlight than those in the low-altitude population.Furthermore,the food resources for lizards in low-altitude habitats were more abundant than those in high-altitude habitats In conclusion,we established that P.vlangalii lizards inhabiting high-altitude sites had larger home ranges than conspecific lizards distributed at a lower altitude,which was associated not only with endogenous factors,such as body mass,but also with habitat-related environmental factors,such as the quality of thermal resources and availability of food. 展开更多
关键词 home range influence factor plateau lizard radio tracking
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Numerical prediction of the long- term soil temperature variations around shallowsections of cross-river road tunnels
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作者 王志明 张巍 +2 位作者 雷长征 丁蓬莱 孙可 《Journal of Southeast University(English Edition)》 EI CAS 2014年第4期480-488,共9页
Considering the coupled heat transfer effect induced by parallel cross-river road tunnels, the long-term soil temperature variations of shallow sections of cross-river tunnels under the river beach are predicted using... Considering the coupled heat transfer effect induced by parallel cross-river road tunnels, the long-term soil temperature variations of shallow sections of cross-river tunnels under the river beach are predicted using the finite difference method for numerical simulation. The boundary conditions and the initial values are determined by in situ observations and numerical iterations.The simulation results indicate that the ultimate calculated steady heat transfer time is 68 years, and most of the heat transfer is completed in 20 years.The initial constant temperature soil surrounding the tunnels is transformed to an annually variable one.An obvious temperature-varying region of the surrounding soil is discovered within 5 m from the tunnel exterior, as well as within the entire range of soil between the two tunnels.The maximum temperature increase value reaches 7.14 ℃ and the maximum peak-to-valley value of annual temperature increase reaches 10 ℃.The temperature variation of soils surrounding tunnels below 10 m is completely controlled by the heat transfer from the tunnels.The coupled heat transfer effect is confirmed because the ultimate steady temperature of soil between the two tunnels is higher than the ones along other positions.Moreover, the regression model comprising a series of univariate functions is proposed for the annual soil temperature fluctuation estimation for the locations varied distances around the tunnel.This investigation is beneficial to gain an insight into the long-term variation tendencies of local engineering geological conditions of the river beach above shallow sections of the cross-river road tunnels. 展开更多
关键词 shield tunnel finite difference method heat influence range steady heat transfer time coupled heat transfer effect
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Comparison Between Computer Simulation of Transport and Diffusion of Cloud Seeding Material Within Stratiform Cloud and the NOAA-14 Satellite Cloud Track 被引量:1
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作者 余兴 戴进 +1 位作者 雷恒池 樊鹏 《Advances in Atmospheric Sciences》 SCIE CAS CSCD 2005年第1期133-141,共9页
A precipitation enhancement operation using an aircraft was conducted from 1415 to 1549 LST 14 March 2000 in Shaanxi Province. The NOAA-14 satellite data received at 1535 LST soon after the cloud seeding shows that a ... A precipitation enhancement operation using an aircraft was conducted from 1415 to 1549 LST 14 March 2000 in Shaanxi Province. The NOAA-14 satellite data received at 1535 LST soon after the cloud seeding shows that a vivid cloud track appears on the satellite image. The length, average width and maximum width of the cloud track are 301 km, 8.3 and 11 km, respectively. Using a three-dimensional numerical model of transport and diffusion of seeding material within stratiform clouds, the spatial concentration distribution characteristics of seeding material at different times, especially at the satellite receiving time, are simulated. The model results at the satellite receiving time are compared with the features of the cloud track. The transported position of the cloud seeding material coincides with the position of the track. The width, shape and extent of diffusion of the cloud seeding material are similar to that of the cloud track. The spatial variation of width is consistent with that of the track. The simulated length of each segment of the seeding line accords with the length of every segment of the track. Each segment of the cloud track corresponds to the transport and diffusion of each segment of the seeding line. These results suggest that the cloud track is the direct physical reflection of cloud seeding at the cloud top. The comparison demonstrates that the numerical model of transport and diffusion can simulate the main characteristics of transport and diffusion of seeding material, and the simulated results are sound and trustworthy. The area, volume, vidth, depth, and lateral diffusive rate corresponding to concentrations 1, 4, and 10 L-1are simulated in order to understand the variations of influencing range. 展开更多
关键词 NOAA satellite data cloud track transport and diffusion numerical simulation influencing range
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Prediction Model of Abutment Pressure Affected by Far-Field Hard Stratum Based on Elastic Foundation Theory
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作者 Zhimin Zhang Tianhe Kang 《Computers, Materials & Continua》 SCIE EI 2021年第1期341-357,共17页
In view of the three-dimensional dynamic abutment pressure,the influence of the far-field hard stratum(FHS)in deep,thick coal seams is indeterminant.Based on elastic foundation theory,a three-dimensional dynamic predi... In view of the three-dimensional dynamic abutment pressure,the influence of the far-field hard stratum(FHS)in deep,thick coal seams is indeterminant.Based on elastic foundation theory,a three-dimensional dynamic prediction model of the abutment pressure was established.Using this model,the dynamic change in the coal seam abutment pressure caused by the movement of the FHS was studied,and a method for determining the dynamic change range of the abutment pressure was developed.The results of the new prediction model of the abutment pressure are slightly higher than the measured values,with an error of 0.51%,which avoids the shortcomings of the results because the Winkler foundation model results are lower than the measured values and have an error of 9.98%.As time progresses,the abutment pressure and its distribution range are affected by the FHS movement,which has the characteristics of gradually increasing dynamic change until the FHS fractures.The peak value of the abutment pressure increases linearly with time,and the influence range increases with time following a power function with an exponent of less than 1.The influence range of the FHS movement on the abutment pressure ahead of the working face,behind the working face,and along the working face is 10 times,25 times,and 17 times the mining thickness,respectively.According to the actual geological parameters,the dynamic change range of the coal seam abutment pressure was determined by drawing an additional stress curve and by determining the threshold value.These research results are of great significance to the partition optimization of the roadway support design of deep,thick coal seams. 展开更多
关键词 Abutment pressure far-field hard stratum Kerr elastic foundation model dynamic change mechanical model influence range
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Analysis on Change Characteristics of Diurnal Temperature Range in Benxi County from 1958 to 2010
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作者 Wang Fuchun Song Jifeng 《Meteorological and Environmental Research》 CAS 2014年第9期1-4,共4页
Based on annual mean maximum and minimum temperatures,diurnal temperature range,precipitation,sunshine,total cloud cover and water barometric pressure data in Benxi County from 1958 to 2010,using statistical analysis,... Based on annual mean maximum and minimum temperatures,diurnal temperature range,precipitation,sunshine,total cloud cover and water barometric pressure data in Benxi County from 1958 to 2010,using statistical analysis,the results show that the annual and seasonal diurnal temperature ranges present significant decreasing tendencies,and the reducing tendency is the most remarkable in winter. Autumn reducing tendency is stronger than that in spring,and it is the weakest in summer. Annual and seasonal average temperatures,average maximum and minimum temperatures all present the remarkable rising trends. Rising trend of the minimum temperature is more significant than that of the maximum temperature. The monthly mean diurnal temperature range also presents reducing tendency,and the most reducing scope appear in January and February. Annual and season diurnal temperature range changes are related to sunshine,mean minimum temperature,mean maximum temperature,precipitation,total cloud cover and water barometric pressure,but various essential factors are different in each season. Annual mean temperature,annual mean minimum temperature,annual mean maximum temperature and annual diurnal temperature range all have sudden changes,but the age is inconsistent. 展开更多
关键词 Diurnal temperature range Change characteristics influence factor China
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桩-浆联合模式下土遗址裂隙注浆加固机制
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作者 崔凯 于翔鹏 +2 位作者 吴国鹏 许鹏飞 葛诚瑞 《岩土力学》 EI CAS CSCD 北大核心 2024年第S01期607-618,共12页
桩-浆联合修复土遗址裂隙加固效果显著,加固机制复杂尚待明晰。基于固体传热、非饱和渗透理论,结合生石灰非等温水化进程和桩-浆-土的动态变化关系,建立了该过程中水-热-力耦合的三维扩散模型并进行求解,通过现场注浆试验过程的实时监... 桩-浆联合修复土遗址裂隙加固效果显著,加固机制复杂尚待明晰。基于固体传热、非饱和渗透理论,结合生石灰非等温水化进程和桩-浆-土的动态变化关系,建立了该过程中水-热-力耦合的三维扩散模型并进行求解,通过现场注浆试验过程的实时监测结果与有限元模拟结果的比对以揭示其加固机制。结果一致表明:石灰桩和浆液中生石灰都在极短时间内达到较高的反应程度,60 min时反应程度分别达到87%和76%;裂隙周边夯土中各物理场均呈现出以浆液和石灰桩为中心,距离裂隙越远数值越低的分布规律;浆液和石灰桩中80%的水分和69%的水化热被有效用于加固过程;归一化处理后得到该过程中温度、水分、膨胀压力作用的有效影响范围分别为裂隙宽度的2.4倍、0.7倍和1.4倍。该研究为桩-浆联合修复土遗址裂隙新方法提供了理论支持。 展开更多
关键词 土遗址 桩-浆联合 水化反应 加固机制 有效影响范围
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用折线法确定避雷针保护范围的防雷漏洞与改进
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作者 郑江 林苗 《现代建筑电气》 2024年第5期1-6,52,共7页
用现行折线法确定避雷针高度为h的保护范围,由于没有考虑h的有效保护范围的影响,单支h及两支等高h之间的保护范围均存在防雷漏洞。分析了这些防雷漏洞,并对折线法进行了改进:设h=30 m时h在0.5h高度处的有效保护半径为r_(h/2)=15 m,h的... 用现行折线法确定避雷针高度为h的保护范围,由于没有考虑h的有效保护范围的影响,单支h及两支等高h之间的保护范围均存在防雷漏洞。分析了这些防雷漏洞,并对折线法进行了改进:设h=30 m时h在0.5h高度处的有效保护半径为r_(h/2)=15 m,h的圆锥体及圆台体保护范围的地面有效保护半径分别为r_(01)=30 m,r_(02)=45 m,推导出当h>30 m时,h对圆锥体的保护角α′及h在任意高度处的保护半径r_(x)的计算公式;取D<2r_(01)或D<2r_(02)限制两支等高h的针间距离,按h_(0)=r_(01)或h_(0)=r_(02)为半径的圆弧确定两支等高h的针间保护范围。改进后随着h的增高,α′减小,r_(h/2)、r_(01)、r_(02)保持不变,单支h的保护范围被拉高变窄,单支h及两支等高h之间的保护范围均在h的有效保护范围之内,有效堵住了折线法的防雷漏洞。 展开更多
关键词 避雷针 保护角 高度影响系数 折线法 保护范围 雷闪距离
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盾构法施工近距离下穿既有隧道变形影响分析 被引量:1
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作者 秦欣 王江锋 《水利与建筑工程学报》 2024年第2期7-11,共5页
为了解盾构法施工近距离下穿对既有隧道影响,依托于实际工程,通过midasGTSNX三维有限元软件仿真模拟新建隧道穿越既有隧道的施工过程,分析既有隧道和土层的变形规律、采用“上小下大”的注浆模式研究注浆压力以及管片环宽对地层变形的... 为了解盾构法施工近距离下穿对既有隧道影响,依托于实际工程,通过midasGTSNX三维有限元软件仿真模拟新建隧道穿越既有隧道的施工过程,分析既有隧道和土层的变形规律、采用“上小下大”的注浆模式研究注浆压力以及管片环宽对地层变形的影响。研究结果表明:当盾构机开挖掌子面不断靠近既有隧道时,施工对既有隧道的影响不断增大,在下穿时影响最大,此区间的隧道沉降值最大,是穿越过程中最危险的地方,在背离后隧道沉降值逐渐减小;地层随注浆压力的增大,施工造成的周围地层变形减少,在地层沉降没有稳定之前,根据地面的沉降情况,可进行二次注浆;环宽设置值的过大或过小都会增大地表沉降值,选取管片环宽时,要综合具体工程条件、施工成本和施工技术等方面考虑。盾构法施工下穿时,上下重叠区间内既有隧道的变形量最大,需提前做出安全施工的预案,确保施工安全。 展开更多
关键词 近距离下穿 既有隧道 变形影响分析 数值模拟 加固措施
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福建地震台网地震定位精度评估
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作者 杨源鸿 林彬华 +4 位作者 李军 陈惠芳 丁炳火 陈辉 林玮瑾 《大地测量与地球动力学》 CSCD 北大核心 2024年第10期1095-1100,共6页
以2018~2022年福建地震台网记录的1 063次M≥2.5地震事件为研究对象,利用地震计、强震仪、烈度计三类台站的观测数据,通过计算不同震级对三类传感器观测范围的理论估计值,采用地震定位精度标准方法对1 063次地震进行定位精度评估,按区域... 以2018~2022年福建地震台网记录的1 063次M≥2.5地震事件为研究对象,利用地震计、强震仪、烈度计三类台站的观测数据,通过计算不同震级对三类传感器观测范围的理论估计值,采用地震定位精度标准方法对1 063次地震进行定位精度评估,按区域(福建、台湾海峡及台湾地区)划分并对比测震台网和三网融合的定位精度。结果表明,三网融合后Ⅰ类精度的地震数量由1.51%提升至3.01%,Ⅱ类精度由5.83%提升至25.31%,Ⅲ类精度由16.27%提升至63.78%,Ⅳ类精度由76.39%降低为7.90%,三网融合对福建地震台网的地震定位精度有较大改善,福建、台湾海峡及台湾地区3个不同区域地震的定位精度有不同程度的提升。本文研究结果可为三网融合在地震速报及编目中的地震定位策略应用提供重要参考与评判依据。 展开更多
关键词 定位精度 预警台网 烈度计 震级 波场影响范围
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图书情报学理论方法跨学科影响力成因要素研究
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作者 张海 石晶 孔晔晗 《情报理论与实践》 CSSCI 北大核心 2024年第4期67-74,共8页
[目的/意义]在新文科和跨学科融合发展的时代背景下,厘清图书情报学理论方法跨学科影响力及形成机制,对于构建信息资源管理学科的学术体系,促进跨学科融合发展,切实提升信息资源管理学科的学术话语权具有重要的理论意义和实践意义。[方... [目的/意义]在新文科和跨学科融合发展的时代背景下,厘清图书情报学理论方法跨学科影响力及形成机制,对于构建信息资源管理学科的学术体系,促进跨学科融合发展,切实提升信息资源管理学科的学术话语权具有重要的理论意义和实践意义。[方法/过程]选取了28名非图书情报学科领域科研人员进行深度访谈和焦点访谈,借鉴扎根理论研究范式对原始访谈数据进行编码分析,构建了图书情报学理论方法跨学科影响力成因要素研究模型。[结果/结论]研究结果显示,图书情报学理论方法在跨学科领域的影响力可以划分为:显性影响、隐性影响、导向影响和潜在影响4个维度。此外还发现,主体因素、学科因素、社会环境和学术媒介是影响图书情报学理论方法跨学科影响力的重要因素。在此基础上,文章提出了图书情报学科需要以国家战略为导向,完善图书情报学科的理论体系和方法体系,扩大学术交流等切实提升图书情报学科学术影响力的对策与建议。 展开更多
关键词 图书情报学 跨学科影响力 扎根理论 隐性影响 学科交叉
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厦门海域文昌鱼资源时空分布和保护 被引量:1
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作者 陈甘霖 王鑫煌 +2 位作者 吴昊 黄昆 缪有庆 《应用海洋学学报》 CAS CSCD 北大核心 2024年第4期659-667,共9页
文昌鱼是研究动物进化的珍贵海洋生物,具有重要的科学研究价值。厦门海域文昌鱼曾经是捕捞的经济鱼种,1991年成立了厦门文昌鱼自然保护区。本文通过回顾不同时期厦门海域文昌鱼资源及其分布情况,得出厦门海域文昌鱼资源整体呈下降趋势,... 文昌鱼是研究动物进化的珍贵海洋生物,具有重要的科学研究价值。厦门海域文昌鱼曾经是捕捞的经济鱼种,1991年成立了厦门文昌鱼自然保护区。本文通过回顾不同时期厦门海域文昌鱼资源及其分布情况,得出厦门海域文昌鱼资源整体呈下降趋势,其中刘五店海域文昌鱼资源时空分布变化较大,前埔海域和南线—十八线海域文昌鱼资源时空分布相对稳定,小嶝岛海域仅有零星分布。不同的历史时期,围填工程、海砂开采、海水养殖和过度捕捞等海洋开发利用活动,影响着厦门海域文昌鱼资源及其分布变化。本文从文昌鱼种群恢复、生境修复等角度出发,总结和浅析现有文昌鱼增殖放流、底质环境修复的理论和实践研究等工作,建议以文昌鱼资源量和栖息面积等为核心指标,构建文昌鱼种群恢复和生境修复的评估指标体系。未来可在扩大调查范围、研究文昌鱼不同生活史阶段环境需求的基础上,建立科学有效的评估体系,开展更为全面和系统的保护和修复工作。 展开更多
关键词 海洋生物学 文昌鱼 分布范围 资源 影响因素 保护 厦门
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磁场对短程硝化微生物群落结构和酶活性的影响
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作者 赵校宇 张凤军 +2 位作者 孙绍钧 孙绍芳 王嘉斌 《济南大学学报(自然科学版)》 CAS 北大核心 2024年第3期295-299,共5页
为了探明磁感应强度对短程硝化系统的影响机制,构建磁性序批式活性污泥法反应器,对比磁感应强度对短程硝化过程氮转化的影响规律,并通过高通量测序等分子生物学手段研究磁场对微生物群落结构和酶活性的影响。结果表明:磁场对短程硝化过... 为了探明磁感应强度对短程硝化系统的影响机制,构建磁性序批式活性污泥法反应器,对比磁感应强度对短程硝化过程氮转化的影响规律,并通过高通量测序等分子生物学手段研究磁场对微生物群落结构和酶活性的影响。结果表明:磁场对短程硝化过程有显著影响,在磁感应强度为10、15 mT的磁场作用下,氨氮去除率低于无磁场对照组的;在磁感应强度为5、10 mT的磁场作用下,所构建反应器的亚硝态氮累积率高于无磁场对照组的;磁场对所构建反应器中微生物群落结构和酶基因相对含量产生影响,当磁感应强度为5 mT时,OLB8菌群、亚硝酸盐氧化酶的相对丰度减小,氨单加氧酶和羟胺脱氢酶的相对丰度增大,亚硝态氮累积效果更优。 展开更多
关键词 磁场 短程硝化 微生物群落 酶活性 影响机制
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基于ABAQUS的气动潜孔锤球齿碎岩及布齿优化
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作者 杨秋明 周兢 +2 位作者 王瑜 夏柏如 吴浩 《钻探工程》 2024年第1期40-50,共11页
为提高坚硬地层大直径潜孔锤的破岩效率与使用寿命,运用ABAQUS软件建立了球齿碎岩仿真模型,对比分析?18 mm球齿在不同钻进参数下冲击切削碎岩过程中的破碎比功、侵入深度、破碎范围与应力影响范围等曲线,优选钻进参数和布齿。分析结果表... 为提高坚硬地层大直径潜孔锤的破岩效率与使用寿命,运用ABAQUS软件建立了球齿碎岩仿真模型,对比分析?18 mm球齿在不同钻进参数下冲击切削碎岩过程中的破碎比功、侵入深度、破碎范围与应力影响范围等曲线,优选钻进参数和布齿。分析结果表明:当钻压为1.2 kN、冲击功为30 J时,对岩石的破碎效率较高,球齿入岩的位移可达0.67 mm,并对岩石进行应力界限划分,得出应力影响范围为43.4 mm;通过双齿冲击切削模拟确定了较为优秀的圈距与间距:圈距取47.4 mm,间距取43.4~51.4 mm;考虑到球齿的磨损,利用圈距与间距对?711 mm大直径潜孔锤进行了优化布齿。 展开更多
关键词 气动潜孔锤 球齿 钻进参数 布齿 应力影响范围 坚硬地层 岩石破碎 ABAQUS
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同牌号油品不同密度差值范围对油品调和影响的探讨
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作者 于林华 曾勇昭 +2 位作者 韦金广 陈先银 黄嵩 《石油库与加油站》 2024年第1期23-26,M0003,M0004,共6页
通过实验室模拟试验和石油库油罐混调试验,分别对汽油和柴油的不同密度差值范围的油品混调时呈现的分层现象进行了试验和分析,结果表明:随着密度差值范围的增大,油品的相溶区域在不断收缩变窄,相溶区域内的密度差幅度也在增大,密度分布... 通过实验室模拟试验和石油库油罐混调试验,分别对汽油和柴油的不同密度差值范围的油品混调时呈现的分层现象进行了试验和分析,结果表明:随着密度差值范围的增大,油品的相溶区域在不断收缩变窄,相溶区域内的密度差幅度也在增大,密度分布分层现象也越来越严重。汽油组的硫含量和辛烷值指标数据以及柴油组的硫含量和闪点指标数据都是同步随着油品混合状态进行分布。为此,建议成品油销售企业制定调和方案时:油品密度差值范围在0~2kg/m^(3)时,大部分的混合区域能呈现混溶状态,可进行调和;密度差值范围在2~4kg/m^(3)时,相溶区域逐渐缩减,分层趋势逐渐显现,可进行调和,但需将管控等级设为中风险级,应做好调和后的取样监测工作;密度差值范围大于4kg/m^(3)后,相溶区域集中在油品交界区域内,已呈现明显的分层现象,管控等级为高风险级,不建议进行调和。 展开更多
关键词 汽油 柴油 密度 差值 范围 调和 影响 探讨
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深厚杂填土地基挤密桩加固效果试验研究
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作者 宋斌 李朋朋 王鹏宇 《工程勘察》 2024年第5期40-43,共4页
在深厚杂填土场地地基处理时,挤密桩由于较好的适用性和经济性而得到广泛应用。但是,在挤密桩的加固效果计算上尚有诸多不足。在夯扩挤密桩试验研究中,通过设置观测标点,研究在以粉土、砂质粉土、黏土及碎石素填土为主的深厚杂填土场地... 在深厚杂填土场地地基处理时,挤密桩由于较好的适用性和经济性而得到广泛应用。但是,在挤密桩的加固效果计算上尚有诸多不足。在夯扩挤密桩试验研究中,通过设置观测标点,研究在以粉土、砂质粉土、黏土及碎石素填土为主的深厚杂填土场地夯扩挤密桩地基处理的效果,判断夯扩挤密桩挤密影响范围,并采用干密度试验比照分析,对定位点测量的结果进行验证。通过综合分析得到挤密桩较精确的地基加固范围,并分析竖直方向加固效果的变化,为类似工程设计提供参考。 展开更多
关键词 杂填土 夯扩挤密桩 挤密影响范围 挤密效应
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7日龄住院早产儿甲状腺功能影响因素及参考值范围探讨
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作者 祁娇 何玺玉 《中国当代儿科杂志》 CAS CSCD 北大核心 2024年第6期625-630,共6页
目的 探讨7日龄早产儿甲状腺功能的影响因素及其参考值范围,以避免临床上不必要的复查和干预。方法 回顾性分析2020年1月—2023年1月住院的685例早产儿资料。依据胎龄和出生体重分为高危组(胎龄<34周或体重<2 000 g;n=228)与低危... 目的 探讨7日龄早产儿甲状腺功能的影响因素及其参考值范围,以避免临床上不必要的复查和干预。方法 回顾性分析2020年1月—2023年1月住院的685例早产儿资料。依据胎龄和出生体重分为高危组(胎龄<34周或体重<2 000 g;n=228)与低危组(胎龄≥34周且出生体重≥2 000 g;n=457)。分析甲状腺功能的影响因素,并计算其95%参考值范围。结果 多元线性回归分析显示,胎龄、出生体重、出生季节、性别、辅助生殖等为甲状腺功能的影响因素(P<0.05)。高危组早产儿的游离三碘甲状腺原氨酸(free triiodothyronine,FT3)、游离甲状腺素(free thyroxine,FT4)、总三碘甲状腺原氨酸(total triiodothyronine,TT3)、总甲状腺素(total thyroxine,TT4)、促甲状腺激素(thyroid stimulating hormone,TSH)参考值范围分别为2.79~5.40 pmol/L、8.80~25.64 pmol/L、0.80~2.15 nmol/L、50.06~165.09 nmol/L、0.80~18.57μIU/mL,低危组的分别为3.08~5.93 pmol/L、11.17~26.24pmol/L、1.02~2.27 nmol/L、62.90~168.95 nmol/L、0.69~13.70μIU/mL。FT3、FT4、TT3、TT4与胎龄呈正相关(P<0.05);FT3、FT4、TT3、TT4与出生体重呈正相关(P<0.05),TSH与出生体重呈负相关(P<0.05)。结论 7日龄早产儿甲状腺功能受胎龄、出生体重等因素影响;7日龄早产儿甲状腺功能参考值范围应基于胎龄及出生体重建立。 展开更多
关键词 甲状腺功能 影响因素 参考值范围 胎龄 早产儿
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