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A Guide to Cheek Augmentation: Single-Point Deep Injection of Hyaluronic Acid Filler at Midface in Close Proximity to Medial Suborbicularis Oculi Fat (SOOF) Area 被引量:1
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作者 Chung-Pin Liang Haw-Yueh Thong 《Journal of Cosmetics, Dermatological Sciences and Applications》 2016年第1期1-8,共8页
Loss of volume in midface can result in an aged, wasted appearance. Osseous and fat atrophy with aging may further contribute to the loss of soft tissue support and midface ptosis. In the aging of periorbital area and... Loss of volume in midface can result in an aged, wasted appearance. Osseous and fat atrophy with aging may further contribute to the loss of soft tissue support and midface ptosis. In the aging of periorbital area and midface, fat atrophy occurs mostly in the suborbicularis oculi fat (SOOF) area. The authors proposed that injection of hyaluronic acid (HA) filler to support the SOOF area could counteract the aging sign due to fat atrophy, restore volume loss and achieve a more youthful appearance. The authors described the treatment of 10 female patients who received CHAP<sup></sup><sup>&reg</sup>-particle hyaluronic acid (CHAP<sup>&reg</sup>-HA) injections for cheek augmentation, using single-point deep injection technique at midface in close proximity to SOOF area. Such approach provides satisfactory cheek augmentation results without significant complications. The authors discussed a rationale for their choice of dermal filler and provided an injection technique for restoring volume in the midface region with CHAP<sup>&reg</sup>-HA. Such technique is relatively quick to perform, have little down time, and result in a high rate of patient satisfaction. 展开更多
关键词 Midface Lift Cheek Augmentation Fat Compartment Suborbicularis Oculi Fat (SOOF) single-point deep injection Hyaluronic Acid (HA) Filler CHAP®-Hyaluronic Acid (Crosslinked Hyaluronic Acid Platform CHAP®-HA) Hyadermis®
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Coot Optimization with Deep Learning-Based False Data Injection Attack Recognition
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作者 T.Satyanarayana Murthy P.Udayakumar +2 位作者 Fayadh Alenezi E.Laxmi Lydia Mohamad Khairi Ishak 《Computer Systems Science & Engineering》 SCIE EI 2023年第7期255-271,共17页
The recent developments in smart cities pose major security issues for the Internet of Things(IoT)devices.These security issues directly result from inappropriate security management protocols and their implementation... The recent developments in smart cities pose major security issues for the Internet of Things(IoT)devices.These security issues directly result from inappropriate security management protocols and their implementation by IoT gadget developers.Cyber-attackers take advantage of such gadgets’vulnerabilities through various attacks such as injection and Distributed Denial of Service(DDoS)attacks.In this background,Intrusion Detection(ID)is the only way to identify the attacks and mitigate their damage.The recent advancements in Machine Learning(ML)and Deep Learning(DL)models are useful in effectively classifying cyber-attacks.The current research paper introduces a new Coot Optimization Algorithm with a Deep Learning-based False Data Injection Attack Recognition(COADL-FDIAR)model for the IoT environment.The presented COADL-FDIAR technique aims to identify false data injection attacks in the IoT environment.To accomplish this,the COADL-FDIAR model initially preprocesses the input data and selects the features with the help of the Chi-square test.To detect and classify false data injection attacks,the Stacked Long Short-Term Memory(SLSTM)model is exploited in this study.Finally,the COA algorithm effectively adjusts the SLTSM model’s hyperparameters effectively and accomplishes a superior recognition efficiency.The proposed COADL-FDIAR model was experimentally validated using a standard dataset,and the outcomes were scrutinized under distinct aspects.The comparative analysis results assured the superior performance of the proposed COADL-FDIAR model over other recent approaches with a maximum accuracy of 98.84%. 展开更多
关键词 False data injection attack security internet of things deep learning coot optimization algorithm
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Injections Attacks Efficient and Secure Techniques Based on Bidirectional Long Short Time Memory Model
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作者 Abdulgbar A.R.Farea Gehad Abdullah Amran +4 位作者 Ebraheem Farea Amerah Alabrah Ahmed A.Abdulraheem Muhammad Mursil Mohammed A.A.Al-qaness 《Computers, Materials & Continua》 SCIE EI 2023年第9期3605-3622,共18页
E-commerce,online ticketing,online banking,and other web-based applications that handle sensitive data,such as passwords,payment information,and financial information,are widely used.Various web developers may have va... E-commerce,online ticketing,online banking,and other web-based applications that handle sensitive data,such as passwords,payment information,and financial information,are widely used.Various web developers may have varying levels of understanding when it comes to securing an online application.Structured Query language SQL injection and cross-site scripting are the two vulnerabilities defined by the OpenWeb Application Security Project(OWASP)for its 2017 Top Ten List Cross Site Scripting(XSS).An attacker can exploit these two flaws and launch malicious web-based actions as a result of these flaws.Many published articles focused on these attacks’binary classification.This article described a novel deep-learning approach for detecting SQL injection and XSS attacks.The datasets for SQL injection and XSS payloads are combined into a single dataset.The dataset is labeledmanually into three labels,each representing a kind of attack.This work implements some pre-processing algorithms,including Porter stemming,one-hot encoding,and the word-embedding method to convert a word’s text into a vector.Our model used bidirectional long short-term memory(BiLSTM)to extract features automatically,train,and test the payload dataset.The payloads were classified into three types by BiLSTM:XSS,SQL injection attacks,and normal.The outcomes demonstrated excellent performance in classifying payloads into XSS attacks,injection attacks,and non-malicious payloads.BiLSTM’s high performance was demonstrated by its accuracy of 99.26%. 展开更多
关键词 Web security SQL injection XSS deep learning RNN LSTM BiLSTM
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Use of High-Resolution Ultrasound (HRU) in the Assessment of Deep Injections of CHAP-Hyaluronic Acid (CHAP-HA) Fillers for Midface Lift 被引量:1
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作者 Hsiao-Tung Lee Haw-Yueh Thong 《Journal of Cosmetics, Dermatological Sciences and Applications》 2018年第3期126-132,共7页
High-resolution ultrasound (HRU) imaging is a useful tool to study hyaluronic acid (HA) filler injection in the face. It is noninvasive, quick, well-tolerated, and can provide in vivo and dynamic information. The form... High-resolution ultrasound (HRU) imaging is a useful tool to study hyaluronic acid (HA) filler injection in the face. It is noninvasive, quick, well-tolerated, and can provide in vivo and dynamic information. The formations of pools or pearls in HA fillers could be observed real time during injection. The plane of injection could be determined accurately, and there were no specimen manipulation artifacts. It was observed that HA gel fillers with differing production technologies showed distinct spread and distribution patterns in the periocular tissues on HRU examination. The authors used HRU to assess deep injections of CHAP-Hyaluronic Acid (CHAP-HA) fillers for midface lift. 10 patients who underwent bilateral midface deep injections using CHAP-HA filler were examined with HRU before and immediately after treatment, and in 2 weeks and one month later. The CHAP-HA appeared as hypoechoic densities within the preperiosteal plane in HRU. CHAP-HA adopted variable morphology within the tissue depending on individual tissue densities and the compliance of the tissues in the plane of injection. CHAP-HA was unidentifiable with surrounding tissue after one month in 13 of the 20 injection sites. HRU allows in vivo study of CHAP-HA injection behavior and could be a tool for further studies of HA-tissue reactions. 展开更多
关键词 CHAP-Hyaluronic Acid (CHAP-HA) FILLER High-Resolution Ultrasound (HRU) MIDFACE Lift deep injectionS Preperiosteal FILLER injectionS
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The accurate location of the injection- induced microearthquakes in German Continental Deep Drilling Program 被引量:1
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作者 TU Yi-min(涂毅敏) +1 位作者 CHEN Yun-tai(陈运泰) 《Acta Seismologica Sinica(English Edition)》 CSCD 2002年第6期616-627,共12页
From August 21, 2000 to October 20, 2000,a fluid injection-induced seismicity experiment has been carried out in the KTB (German Continental Deep Drilling Program). The KTB seismic network recorded more than 2 700 eve... From August 21, 2000 to October 20, 2000,a fluid injection-induced seismicity experiment has been carried out in the KTB (German Continental Deep Drilling Program). The KTB seismic network recorded more than 2 700 events. Among them 237 events were of high signal-to-noise ratio, and were processed and accurately located. When the events were located, non KTB events were weeded out by Wadatis method. The standard deviation, mean and median were obtained by Jackknife's technique, and finally the events were accurately located by Gei-gers method so that the mean error is about 0.1 km. No earthquakes with focal depth greater than 9.3 km, which is nearly at the bottom of the hole, were detected. One of the explanation is that at such depths the stress levels may not close to the rocks frictional strength so that failure could not be induced by the relatively small perturbation in pore pressure. Or at these depths there may be no permeable, well-oriented faults. This depth may be in close proximity to the bottom of the hole to the brittle-ductile transition, even in this relatively stable interior of the in-teraplate. This phenomenon is explained by the experimental results and geothermal data from the superdeep bore-hole. 展开更多
关键词 scientific deep drilling fluid-injection induced seismicity earthquake location Jackknife method brittle-ductile transition
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Possible link between long-term and short-term water injections and earthquakes in salt mine and shale gas site in Changning,south Sichuan Basin, China 被引量:28
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作者 XingLin Lei ZhiWei Wang JinRong Su 《Earth and Planetary Physics》 CSCD 2019年第6期510-525,共16页
Late at night on 17 June 2019,a magnitude 6.0 earthquake struck Shuanghe Town and its surrounding area in Changning County,Sichuan,China,becoming the largest earthquake recorded within the southern Sichuan Basin.A ser... Late at night on 17 June 2019,a magnitude 6.0 earthquake struck Shuanghe Town and its surrounding area in Changning County,Sichuan,China,becoming the largest earthquake recorded within the southern Sichuan Basin.A series of earthquakes with magnitudes up to 5.6 occurred during a short period after the mainshock,and we thus refer to these earthquakes as the Changning M6 earthquake sequence(or swarm).The mainshock was located very close to a salt mine,into which for^3 decades fresh water had been extensively injected through several wells at a depth of 2.7–3 km.It was also near(within^15 km)the epicenter of the 18 December 2018 M5.7 Xingwen earthquake,which is thought to have been induced by shale gas hydraulic fracturing(HF),prompting questions about the possible involvement of industrial activities in the M6 sequence.Following previous studies,this paper focuses on the relationship between injection and seismicity in the Shuanghe salt field and its adjacent Shangluo shale gas block.Except for a period of serious water loss after the start of cross-well injection in 2005–2006,the frequency of earthquakes shows a slightly increasing tendency.Overall,there is a good correlation between the event rate in the Shuanghe area and the loss of injected water.More than 400 M≥3 earthquakes,including 40 M≥4 and 5 M≥5 events,had been observed by the end of August 2019.Meanwhile,in the Shangluo area,seismicity has increased during drilling and HF operations(mostly in vertical wells)since about 2009,and dramatically since the end of 2014,coincident with the start of systematic HF in the area.The event rate shows a progressively increasing background with some fluctuations,paralleling the increase in HF operations.More than 700 M≥3 earthquakes,including 10 M≥4 and 3 M≥5 in spatially and temporally clustered seismic events,are correlated closely with active fracturing platforms.Well-resolved centroid moment tensor results for M≥4 earthquakes were shown to occur at very shallow depths around shale formations with active HF,in agreement with some of the clusters,which occurred within the coverage area of temporary or new permanent monitoring stations and thus have been precisely located.After the Xingwen M5.7 earthquake,seismic activity in the salt well area increased significantly.The Xingwen earthquake may have created a unidirectional rupture to the NNW,with an end point close to the NW-trending fault of the Shuanghe earthquake.Thus,a fault in the Changning anticline might have terminated the fault rupture of the Xingwen earthquake,possibly giving the Xingwen earthquake a role in promoting the Changning M6 event. 展开更多
关键词 Changning EARTHQUAKE injection-induced EARTHQUAKE deep WELL injection hydraulic FRACTURING salt WELL mine SHALE gas
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Potential assessment of CO_(2)geological storage based on injection scenario simulation:A case study in eastern Junggar Basin 被引量:3
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作者 Xin Ma Dong-guang Wen +6 位作者 Guo-dong Yang Xu-feng Li Yu-jie Diao Hai-hai Dong Wei Cao Shu-guo Yin Yan-mei Zhang 《Journal of Groundwater Science and Engineering》 2021年第4期279-291,共13页
Carbon Capture and Storage(CCS)is one of the effective means to deal with global warming,and saline aquifer storage is considered to be the most promising storage method.Junggar Basin,located in the northern part of X... Carbon Capture and Storage(CCS)is one of the effective means to deal with global warming,and saline aquifer storage is considered to be the most promising storage method.Junggar Basin,located in the northern part of Xinjiang and with a large distribution area of saline aquifer,is an effective carbon storage site.Based on well logging data and 2D seismic data,a 3D heterogeneous geological model of the Cretaceous Donggou Formation reservoir near D7 well was constructed,and dynamic simulations under two scenarios of single-well injection and multi-well injection were carried out to explore the storage potential and CO2 storage mechanism of deep saline aquifer with real geological conditions in this study.The results show that within 100 km^(2)of the saline aquifer of Donggou Formation in the vicinity of D7 well,the theoretical static CO_(2)storage is 71.967×106 tons(P50)①,and the maximum dynamic CO_(2)storage is 145.295×106 tons(Case2).The heterogeneity of saline aquifer has a great influence on the spatial distribution of CO_(2)in the reservoir.The multi-well injection scenario is conducive to the efficient utilization of reservoir space and safer for storage.Based on the results from theoretical static calculation and the dynamic simulation,the effective coefficient of CO_(2)storage in deep saline aquifer in the eastern part of Xinjiang is recommended to be 4.9%.This study can be applied to the engineering practice of CO_(2)sequestration in the deep saline aquifer in Xinjiang. 展开更多
关键词 CO_(2)geological storage deep saline aquifer Potential assessment injection scenarios Numerical simulation Junggar Basin
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Optimal Hybrid Deep Learning Enabled Attack Detection and Classificationin IoT Environment
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作者 Fahad F.Alruwaili 《Computers, Materials & Continua》 SCIE EI 2023年第4期99-115,共17页
The Internet of Things (IoT) paradigm enables end users to accessnetworking services amongst diverse kinds of electronic devices. IoT securitymechanism is a technology that concentrates on safeguarding the devicesand ... The Internet of Things (IoT) paradigm enables end users to accessnetworking services amongst diverse kinds of electronic devices. IoT securitymechanism is a technology that concentrates on safeguarding the devicesand networks connected in the IoT environment. In recent years, False DataInjection Attacks (FDIAs) have gained considerable interest in the IoT environment.Cybercriminals compromise the devices connected to the networkand inject the data. Such attacks on the IoT environment can result in a considerableloss and interrupt normal activities among the IoT network devices.The FDI attacks have been effectively overcome so far by conventional threatdetection techniques. The current research article develops a Hybrid DeepLearning to Combat Sophisticated False Data Injection Attacks detection(HDL-FDIAD) for the IoT environment. The presented HDL-FDIAD modelmajorly recognizes the presence of FDI attacks in the IoT environment.The HDL-FDIAD model exploits the Equilibrium Optimizer-based FeatureSelection (EO-FS) technique to select the optimal subset of the features.Moreover, the Long Short Term Memory with Recurrent Neural Network(LSTM-RNN) model is also utilized for the purpose of classification. At last,the Bayesian Optimization (BO) algorithm is employed as a hyperparameteroptimizer in this study. To validate the enhanced performance of the HDLFDIADmodel, a wide range of simulations was conducted, and the resultswere investigated in detail. A comparative study was conducted between theproposed model and the existing models. The outcomes revealed that theproposed HDL-FDIAD model is superior to other models. 展开更多
关键词 False data injection attacks hyperparameter optimizer deep learning feature selection IOT SECURITY
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深沟球轴承塑料保持架的联合仿真优化
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作者 宁仲 李哲 +2 位作者 董胤喆 黄明 孙小波 《轴承》 北大核心 2024年第8期12-17,共6页
为改善深沟球轴承塑料保持架的注塑变形问题,以锁口端部收缩值为优化评价指标,采用模流分析对保持架浇口数量、加强筋形状以及玻纤含量进行优化选择,通过Minitab软件设计响应曲面试验并结合分类回归树(CART)模型获得注塑工艺参数的最优... 为改善深沟球轴承塑料保持架的注塑变形问题,以锁口端部收缩值为优化评价指标,采用模流分析对保持架浇口数量、加强筋形状以及玻纤含量进行优化选择,通过Minitab软件设计响应曲面试验并结合分类回归树(CART)模型获得注塑工艺参数的最优预测组合。结果表明,优化后锁口端部收缩值由2.461 mm降至1.092 mm,下降55.63%,保持架注塑变形问题得到明显改善。再基于Helius联合仿真对保持架的熔接痕强度进行分析,将模流分析结果映射到ANSYS并通过结构求解器进行运算,证明了优化后的深沟球轴承塑料保持架无失效风险,熔接痕处强度满足要求。 展开更多
关键词 滚动轴承 深沟球轴承 保持架 注塑 有限元分析
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水泥分解炉SNCR脱硝系统的深度强化学习多目标优化控制研究
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作者 刘定平 吴泽豪 《中国电机工程学报》 EI CSCD 北大核心 2024年第12期4815-4825,I0017,共12页
选择性非催化还原(selective non-catalytic reduction,SNCR)脱硝过程的工艺参数优化可以有效减少水泥分解炉NO_(x)排放和脱硝运行成本。以某水泥分解炉为研究对象,建立基于LightGBM的NO_(x)浓度预测模型,以脱硝成本和NO_(x)浓度最小化... 选择性非催化还原(selective non-catalytic reduction,SNCR)脱硝过程的工艺参数优化可以有效减少水泥分解炉NO_(x)排放和脱硝运行成本。以某水泥分解炉为研究对象,建立基于LightGBM的NO_(x)浓度预测模型,以脱硝成本和NO_(x)浓度最小化为优化目标,采用深度确定性策略梯度(deep deterministic policy gradient,DDPG)算法对水泥分解炉掺烧污泥协同SNCR脱硝过程的相关工艺参数进行优化控制建模。结果表明,NO_(x)浓度预测模型均方根误差(root mean squared error,RMSE)为6.8,平均绝对百分比误差(mean absolute percentage error,MAPE)为3.48%;采用DDPG算法可以对相关工艺参数进行优化,喷氨量和污泥掺烧量分别为427.87 L/h和9.78 t/h时,NO_(x)排放浓度为225.99 mg/(Nm^(3)),脱硝运行成本为1 747.8元/h。该优化结果与其他优化算法结果和常规工况对比,NO_(x)排放浓度和脱硝运行成本均呈现不同程度下降;对模型进行仿真及效果验证可知,所建立模型能输出合理的喷氨量和污泥掺烧量组合,减少SNCR出口NO_(x)浓度波动,有效降低NO_(x)排放浓度和脱硝成本,可实现对SNCR脱硝系统的多目标优化控制。该结果可为基于智能算法的水泥分解炉SNCR脱硝的多目标优化控制设计提供一定参考。 展开更多
关键词 喷氨 污泥掺烧 选择性非催化还原优化控制 LightGBM 强化学习 深度确定性策略梯度
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超深层断控碳酸盐岩油藏地质力学建模及其在开发中的应用
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作者 蔡振忠 张辉 +5 位作者 徐珂 尹国庆 王志民 王海应 钱子维 张禹 《石油实验地质》 CAS CSCD 北大核心 2024年第4期868-879,共12页
为提高超深断控碳酸盐岩油藏的开发效益,通过开展大尺寸岩样力学实验,揭示高角度—近直立断裂面变形与连通机理;基于高压注水提采的力学与流动耦合原理,通过地质力学建模,明确了断控碳酸盐岩油藏现今地应力场和断裂活动性分布规律;发现... 为提高超深断控碳酸盐岩油藏的开发效益,通过开展大尺寸岩样力学实验,揭示高角度—近直立断裂面变形与连通机理;基于高压注水提采的力学与流动耦合原理,通过地质力学建模,明确了断控碳酸盐岩油藏现今地应力场和断裂活动性分布规律;发现不同方位的断裂活动性以及不同部位的缝洞体连通性有明显差异,进而分析了不同井眼轨迹的开发效果,提出了地质工程一体化工作方法,科学指导井眼轨迹设计和注水方案优化。结果表明:①走滑断裂变形中的大尺度破碎体和高角度裂缝系统是影响储层品质的关键因素,高压注水一方面能够激活先存裂缝,一方面还能在先存裂缝基础上发生延伸扩展,甚至可以产生新的裂缝,促进了断控缝洞体在纵横向上的互相连通;②高压注水过程中断裂体内部发生力学与流动之间的耦合变化,渗流环境得到改善,通过循环举升,从而提高油气采收率;③根据断裂体形态、产状以及断裂面动态剪切变形连通性,可优选定向井最佳井点和井眼轨迹,并优化注水方案;④塔里木盆地断控油藏试验区通过高压注水,采收率提高5个百分点,该方法为超深断控型油藏高效开发提供了较好的理论依据和技术支撑。 展开更多
关键词 超深层 断控碳酸盐岩油藏 缝洞体 地质力学 断裂活动性 井眼轨迹 注水开发 地质工程一体化
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深沟球轴承喷油润滑搅油损失研究 被引量:1
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作者 胡帅 徐翔宇 +2 位作者 冯伟 宫武旗 桂鹏 《润滑与密封》 CAS CSCD 北大核心 2024年第1期1-8,共8页
为了揭示喷油润滑时深沟球轴承搅油损失随喷油润滑条件的变化,提高齿轮箱综合传动系统的性能,建立深沟球轴承喷油润滑下的数值计算模型,并用SKF模型进行验证。采用数值模拟和设计正交方案的方法研究喷油润滑时深沟球轴承内部流场运动状... 为了揭示喷油润滑时深沟球轴承搅油损失随喷油润滑条件的变化,提高齿轮箱综合传动系统的性能,建立深沟球轴承喷油润滑下的数值计算模型,并用SKF模型进行验证。采用数值模拟和设计正交方案的方法研究喷油润滑时深沟球轴承内部流场运动状态,以及在不同工况参数下深沟球轴承喷油润滑的搅油损失,并通过极差分析和方差分析确定各个因素对轴承搅油损失的影响程度。研究表明:在喷油润滑过程中,外圈表面润滑油体积分数随着润滑油的进入不断提高,并且逐渐趋于均匀稳定,而内圈表面润滑油体积分数则始终很低;喷嘴角度对轴承内部润滑和搅油功率损失影响很大,当喷嘴朝向外圈时,搅油力矩最小,但润滑性能较差,当喷嘴朝向内圈时,润滑性能最好,但搅油力矩稍大;各个因素对轴承搅油损失影响由大到小顺序为节圆直径、转速、喷油压力、喷嘴直径、温度。研究结果对探究深沟球轴承喷油润滑搅油机制和提升车辆传动效率提供了重要的设计和理论参考。 展开更多
关键词 深沟球轴承 搅油损失 喷油润滑 正交试验 数值模拟
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深层低渗凝析气藏气驱适应性研究
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作者 李中超 齐桂雪 +2 位作者 罗波波 许寻 陈华 《油气藏评价与开发》 CSCD 北大核心 2024年第3期324-332,F0002,共10页
针对深层低渗凝析气藏由衰竭开采转变为气驱开发过程中适应性不明确的问题,综合采用PVT(地层流体高压物性)分析仪、长岩心驱替物理模拟技术和数值模拟计算方法,开展了一系列评价研究。通过对比分析注CO_(2)、天然气(伴生气、CH_(4))、N_... 针对深层低渗凝析气藏由衰竭开采转变为气驱开发过程中适应性不明确的问题,综合采用PVT(地层流体高压物性)分析仪、长岩心驱替物理模拟技术和数值模拟计算方法,开展了一系列评价研究。通过对比分析注CO_(2)、天然气(伴生气、CH_(4))、N_(2)对凝析气体系高压物性影响与提高凝析油采出程度情况,明确了深层低渗凝析气藏气驱的适应性。实验结果表明:CO_(2)在凝析油中的溶解度和溶解气油比最大,具有较强降低凝析气藏饱和压力和露点压力的特点,提高凝析油采出程度的效果最佳。同时,采用长岩心物理模拟技术针对CO_(2)驱进行了注入时机、注入方式、注气速度优化研究,明确了在露点压力以上脉冲式注气效果更好,为注气开发技术政策及现场方案的实施提供数据支撑。 展开更多
关键词 凝析气藏 深层低渗 注气介质 气驱适应性 参数优化
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基于DL-BiGRU多特征融合的注塑件尺寸预测方法
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作者 钱庆杰 余军合 +2 位作者 战洪飞 王瑞 胡健 《浙江大学学报(工学版)》 EI CAS CSCD 北大核心 2024年第3期646-654,共9页
为了充分挖掘注塑成型过程中模腔内的高频时序特征和注塑成型机状态特征,提出基于双层双向门控循环单元网络(DL-BiGRU)的多特征融合注塑件尺寸预测方法.分析膜腔内传感器高频时序特征与注塑件尺寸间的关联性,采用DL-BiGRU网络从高频数... 为了充分挖掘注塑成型过程中模腔内的高频时序特征和注塑成型机状态特征,提出基于双层双向门控循环单元网络(DL-BiGRU)的多特征融合注塑件尺寸预测方法.分析膜腔内传感器高频时序特征与注塑件尺寸间的关联性,采用DL-BiGRU网络从高频数据中自动提取时序特征,表征注塑件成型过程状态变化特性.通过采样模腔内高频时序数据进行展成平铺,表征注塑成型的瞬时特征.融合时序特征、瞬时特征和成型机状态特征,构建端到端的深度学习多特征融合框架.将上述3种特征融合并联合训练,提升注塑件尺寸预测精度.在注塑成型数据集上进行模型验证,预测尺寸平均均方误差为4.7×10^(-4) mm^(2),最小误差波动为10^(-5) mm^(2)量级,模型具有较高的预测精度和稳定性. 展开更多
关键词 注塑成型 深度学习 双向门控循环单元网络(BiGRU) 多特征融合 尺寸预测
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微球调驱技术在深部堵塞特征油藏的应用研究
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作者 范敏杰 韩小龙 +2 位作者 闫剑锋 王鹏 杨雷 《石油化工应用》 CAS 2024年第5期65-69,共5页
随着油藏注水开发时间延长,水驱状况变差,含水率逐年上升,水驱效率下降,严重影响油藏的采收率。一般认为注水开发过程中会发生孔喉被注水冲刷变化、微裂缝开启等导致的注水突进,往往忽略深部堵塞对水驱的影响。针对油层深部堵塞缺乏研... 随着油藏注水开发时间延长,水驱状况变差,含水率逐年上升,水驱效率下降,严重影响油藏的采收率。一般认为注水开发过程中会发生孔喉被注水冲刷变化、微裂缝开启等导致的注水突进,往往忽略深部堵塞对水驱的影响。针对油层深部堵塞缺乏研究认识,治理过程中缺乏有效措施,影响此类油藏的开发效果。本文通过对典型的低渗透注水开发油藏分析深部堵塞特征,在此基础上开展微球调驱矿场试验。从效果来看,微球调驱技术与这种深部堵塞油藏适应性较好,通过微球吸水膨胀封堵深部水驱通道,表面活性剂疏通堵塞通道,有效改善水驱,取得了较好的控水稳油效果,为同类型油藏的稳产工作提供科学依据。 展开更多
关键词 注水开发 深部堵塞 微球调驱
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精密轴承用PEEK保持架结构及注塑工艺优化
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作者 董胤喆 宁仲 +2 位作者 李建星 孙小波 席博伦 《轴承》 北大核心 2024年第4期36-39,47,共5页
针对原PEEK保持架兜孔无锁口,采用侧向抽芯机构进行注塑加工时外圆精度低的问题,将保持架兜孔分成内外两部分且设计为球面,注塑模具采用单分型面注塑模结构。并对注塑工艺浇口结构和浇口数量进行优化,基于正交试验得到最优工艺参数为模... 针对原PEEK保持架兜孔无锁口,采用侧向抽芯机构进行注塑加工时外圆精度低的问题,将保持架兜孔分成内外两部分且设计为球面,注塑模具采用单分型面注塑模结构。并对注塑工艺浇口结构和浇口数量进行优化,基于正交试验得到最优工艺参数为模具温度180℃、熔体温度390℃、保压时间5 s和保压压力55 MPa。实际加工表明:外径面圆度不大于0.15 mm占86%;拉伸强度远高于65 MPa;200℃高温摩擦系数平均值为0.195,磨痕宽度平均值为0.9625 mm,磨损量平均值为0.1394 mm^(3);与相应公差等级套圈、球合套后,轴承旋转精度达到P4,振动值达到Z4。 展开更多
关键词 滚动轴承 深沟球轴承 保持架 工程塑料 注塑 翘曲 正交试验 模具设计
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深部煤系储层缝间干扰多裂缝同步扩展规律试验研究
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作者 陈志杰 王开 +4 位作者 张小强 姜玉龙 丁一 侯建 王文伟 《矿业安全与环保》 CAS 北大核心 2024年第2期74-81,89,共9页
为研究深部煤系储层缝间干扰多裂缝同步扩展规律,采用自行研制的TCHFSM-I型大尺寸真三轴压裂渗流模拟装置,开展不同压裂孔间距、不同注液速率对多裂缝同步扩展规律的影响试验。通过观察和分析压裂过程中裂缝扩展形态、注液压力演化规律... 为研究深部煤系储层缝间干扰多裂缝同步扩展规律,采用自行研制的TCHFSM-I型大尺寸真三轴压裂渗流模拟装置,开展不同压裂孔间距、不同注液速率对多裂缝同步扩展规律的影响试验。通过观察和分析压裂过程中裂缝扩展形态、注液压力演化规律,以及声发射动态响应特征和注液流量演化特征,结果表明:压裂孔间距较小时,左右两侧裂缝扩展长度大于中部裂缝,随着压裂孔间距增大,左中右3条裂缝均衡扩展;增大注液速率可以使起裂压力增高,多裂缝长度增加,有效提高储层改造体积;增大压裂孔间距和注液速率,可以使左中右3个压裂孔的注液流量占比更均衡。 展开更多
关键词 深部煤系 多孔水力压裂 缝间应力干扰 压裂孔间距 注液速率 声发射特征 流量演化规律
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基于改进深度强化学习的注采调控模型研究
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作者 陈锐 张强 曾俊玮 《长春理工大学学报(自然科学版)》 2024年第3期77-83,共7页
提出一种基于改进深度强化学习的注采调控模型。首先,建立以最大化经济效益为目标函数的注采调控强化环境。其次,针对模型参数量大、网络内部协变量位移多等问题,提出一种改进双重深度Q网络的深度强化学习方法,应用批量归一化技术逐层... 提出一种基于改进深度强化学习的注采调控模型。首先,建立以最大化经济效益为目标函数的注采调控强化环境。其次,针对模型参数量大、网络内部协变量位移多等问题,提出一种改进双重深度Q网络的深度强化学习方法,应用批量归一化技术逐层归一化模型的输入数据,增强模型的泛化能力;再通过剪枝模块压缩模型体积,加速网络的训练过程,引入动态ε策略思想提高模型的鲁棒性和稳定性。最后,将所提模型同其他模型进行对比,实验结果表明,所提模型能获得更高、更稳定的平均累计奖励和更快的收敛速度和运行速度。 展开更多
关键词 注采调控 深度强化学习 剪枝 批量归一化 双重深度Q网络
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秸秆还田方式对土壤理化性质和玉米产量的影响
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作者 王治统 凌俊 +6 位作者 刘子熙 赵德强 李泽学 周顺利 袁兴茂 李霄鹤 温媛 《中国生态农业学报(中英文)》 CAS CSCD 北大核心 2024年第4期663-674,共12页
高强度集约化农业生产导致耕地质量下降、农田土壤退化,而秸秆还田是改善土壤环境、提高土壤有机质的重要途径。目前的秸秆还田方式主要针对表层土壤,忽略了对底土质量的改善效果。本研究设置了秸秆富集深层还田、秸秆覆盖还田、秸秆浅... 高强度集约化农业生产导致耕地质量下降、农田土壤退化,而秸秆还田是改善土壤环境、提高土壤有机质的重要途径。目前的秸秆还田方式主要针对表层土壤,忽略了对底土质量的改善效果。本研究设置了秸秆富集深层还田、秸秆覆盖还田、秸秆浅旋还田、秸秆深翻还田、秸秆不还田5种秸秆还田方式,以探究不同秸秆还田方式对不同土层土壤理化性质和玉米产量的影响,为高效利用秸秆资源、提高土壤质量和作物产量提供科学依据。本研究结果表明:秸秆覆盖还田提高了0~20 cm土层土壤含水量、有机碳含量、氮循环酶活性;深翻还田提高了表层土壤水分含量与磷循环酶活性;秸秆富集深层还田显著降低了20~40 cm土层土壤容重、增加了土壤含水量、有机碳含量、全氮含量、矿质氮含量以及胞外酶活性。与不还田相比,秸秆还田处理下玉米产量显著提高13.4%~21.0%。因此,秸秆还田是秸秆资源有效利用的重要方式,有利于改善农田土壤环境,提高土壤养分含量,减少化肥使用,促进作物增产,对农业可持续发展具有重要意义。秸秆富集深层还田对于改善底土质量,扩大土壤碳库,提高耕地质量和土地生产力具有重要作用,可以作为构建深厚肥沃耕层的有效措施。 展开更多
关键词 秸秆还田 土壤理化性质 玉米产量 土壤酶 秸秆富集深层还田
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深部热疗联合重组人血管内皮抑制素注射液及AP方案治疗晚期非小细胞肺癌的近期疗效观察
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作者 李超 肖敬 周红梅 《临床和实验医学杂志》 2024年第4期345-349,共5页
目的探讨深部热疗联合重组人血管内皮抑制素注射液及培美曲塞联合顺铂(AP方案)治疗晚期非小细胞肺癌(NSCLC)的近期疗效。方法回顾性分析2016年1月至2022年1月河北省第七人民医院收治的120例晚期NSCLC患者的相关资料,按照治疗方法不同将... 目的探讨深部热疗联合重组人血管内皮抑制素注射液及培美曲塞联合顺铂(AP方案)治疗晚期非小细胞肺癌(NSCLC)的近期疗效。方法回顾性分析2016年1月至2022年1月河北省第七人民医院收治的120例晚期NSCLC患者的相关资料,按照治疗方法不同将患者分为研究组(n=59)和对照组(n=61)。研究组患者采用深部热疗联合重组人血管内皮抑制素注射液及AP方案治疗,对照组患者采用重组人血管内皮抑制素注射液及AP方案。观察两组患者的近期疗效[客观反应率(ORR)、疾病控制率(DCR)],治疗前、治疗后3个月的血清肿瘤标志物[神经元特异性烯醇化酶(NSE)、糖类抗原125(CA125)、细胞角质素片段抗原(Cyfra21-1)及癌胚抗原(CEA)]水平、生活质量评分(KPS)评分]、血常规指标[红细胞计数(RBC)、白细胞计数(WBC)、血小板计数(PLT)]以及不良反应发生情况。结果研究组ORR、DCR分别为15.25%、57.63%,均高于对照组(3.28%、36.07%),差异均有统计学意义(P<0.05)。治疗3个月后,两组NSE、CA125、Cyfra21-1、CEA水平均低于治疗前,且研究组治疗后NSE、CA125、Cyfra21-1、CEA水平分别为(15.23±5.06)ng/mL、(50.16±5.12)U/mL、(6.52±2.03)ng/mL、(30.17±4.17)ng/mL,均低于对照组[(20.16±5.04)ng/mL、(80.24±5.22)U/mL、(10.25±3.09)ng/mL、(60.22±4.17)ng/mL],差异均有统计学意义(P<0.05)。研究组KPS改善率为77.97%,高于对照组(57.38%),差异有统计学意义(P<0.05)。治疗3个月后,两组RBC、WBC、PLT值均较治疗前降低,研究组RBC、WBC、PLT值分别为(3.61±0.12)×10^(12)、(3.98±1.07)×10^(9)、(210.23±30.16)×10^(9),均高于对照组[(3.50±0.11)×10^(12)、(3.12±1.03)×10^(9)、(198.24±20.17)×10^(9)],差异均有统计学意义(P<0.05)。研究组0~Ⅳ级胃肠道不适、肝损伤、肾损伤、贫血不良反应发生率与对照组比较,差异均有统计学意义(P<0.05),研究组各种不良反应的严重程度低于对照组。结论深部热疗联合重组人血管内皮抑制素注射液及AP方案可有效提高晚期NSCLC患者的近期疗效,降低肿瘤标志物水平,改善生活质量和血常规,减少不良反应发生,值得临床推广和应用。 展开更多
关键词 非小细胞肺癌 深部热疗 重组人血管内皮抑制素注射液 AP方案 近期疗效 不良反应
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