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Spatiotemporal Evolution and Linkage Analysis of Mutton Price in Xinjiang
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作者 Yulin YANG jian xu Lean YU 《Journal of Systems Science and Information》 CSCD 2024年第5期667-689,共23页
The mutton industry plays a pivotal role in the animal husbandry industry of Xinjiang Uygur Autonomous Region.To better monitor the volatility movement and risk warning of mutton price,the fluctuation characteristics ... The mutton industry plays a pivotal role in the animal husbandry industry of Xinjiang Uygur Autonomous Region.To better monitor the volatility movement and risk warning of mutton price,the fluctuation characteristics of mutton prices and the future trend of prices are analyzed systematically.On the one hand,the Hodrick Prescott(HP)filter method is used to analyze the long-term trends and cyclical characteristics of mutton prices in Xinjiang and explored the spatial evolution characteristics of mutton price fluctuations in various regions of Xinjiang.On the other hand,the Threshold Auto-Regressive(TAR)model is used to analyze the linkage relationship between mutton prices and the prices of other livestock products.The empirical results show that 1)the overall volatility of mutton price in Xinjiang is high,showing a trend of rising first,then falling and then rising from the temporal perspective.2)At the regional level,the price in the south is higher than that of the north,showing a decreasing trend from south to north on the whole from the spatial viewpoint.3)From the linkage relationship perspective,mutton and beef are complementary in the short term,but they are substitutes each other in the long term.This paper explores the characteristics of mutton price fluctuations in Xinjiang from the single time series of mutton prices and the linkage with other livestock products,which provides a reliable basis for the monitoring and risk warning of mutton price fluctuation. 展开更多
关键词 mutton price fluctuation spatiotemporal volution linkage analysis Hodrick Prescott filtering method threshold autoregressive model
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不同预时效挤压态Mg−Gd−Y−Zn−Zr合金的再结晶行为和强化机制 被引量:1
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作者 徐健 郑杰 +5 位作者 刘莞尔 黄有旺 闫钊鸣 张治民 王强 薛勇 《Transactions of Nonferrous Metals Society of China》 SCIE EI CAS CSCD 2024年第2期480-503,共24页
通过控制预时效时间制备3种不同状态的试样,研究不同预时效状态对挤压态Mg−9.5Gd−4Y−2.2Zn−0.5Zr(质量分数,%)合金的动态再结晶行为(DRX)和性能的影响。结果表明,欠时效挤压(UAE)样品的细晶体积分数为17.4%,而峰时效挤压(PAE)和过时效挤... 通过控制预时效时间制备3种不同状态的试样,研究不同预时效状态对挤压态Mg−9.5Gd−4Y−2.2Zn−0.5Zr(质量分数,%)合金的动态再结晶行为(DRX)和性能的影响。结果表明,欠时效挤压(UAE)样品的细晶体积分数为17.4%,而峰时效挤压(PAE)和过时效挤压(OAE)样品的细晶体积分数分别达到89.7%和50.4%。在晶粒内部和晶界处分布的致密、细小的β颗粒相通过粒子激发形核机制显著提高了形核位点和位错密度。然而,致密针状γ'相抑制位错滑移,延迟DRX形核。PEA和OAE样品中细小晶粒的差异归因于原始颗粒相的数量和尺寸的不同,而其拉伸性能的差异归因于不同的显微组织。由于晶界强化和析出强化机制的贡献更大,PAE样品具有更优异的拉伸性能。 展开更多
关键词 Mg−Gd−Y−Zn−Zr合金 预时效处理 再结晶行为 强化机制 粒子刺激形核
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钻柱腐蚀疲劳寿命评价和影响因素分析 被引量:1
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作者 苏堪华 刘德平 +4 位作者 简旭 孙政 万立夫 卓云 余星颖 《钻探工程》 2024年第1期15-22,共8页
油气钻井过程中钻柱受力复杂,容易发生断裂情况,根据现场情况评价钻柱腐蚀疲劳寿命可以为钻柱安全使用提供依据。从现场实用角度,通过轴向力、循环应力和疲劳极限的计算,对比了基于疲劳系数、寿命百分数和旋转计数的钻柱疲劳评价方法,... 油气钻井过程中钻柱受力复杂,容易发生断裂情况,根据现场情况评价钻柱腐蚀疲劳寿命可以为钻柱安全使用提供依据。从现场实用角度,通过轴向力、循环应力和疲劳极限的计算,对比了基于疲劳系数、寿命百分数和旋转计数的钻柱疲劳评价方法,并考虑了腐蚀的影响。分析结果表明,当在严重狗腿度的井段钻进时,弯曲应力和屈曲增加将加快钻柱疲劳失效;当对应的机械钻速降低、转速增加时,钻柱的剩余使用寿命将进一步降低;当发生较严重的腐蚀时,钻柱剩余使用寿命将迅速降低。在高抗拉井段和狗腿度变化大的井段的钻柱应定期倒换使用,以保障现场钻具安全规范使用。 展开更多
关键词 钻柱 疲劳 腐蚀 屈曲 寿命评价 油气钻井
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Conversion therapy of a giant hepatocellular carcinoma with portal vein thrombus and inferior vena cava thrombus:A case report and review of literature 被引量:1
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作者 Wen-Jie Song jian xu +5 位作者 Ye Nie Wei-Min Li jian-Ping Li Li Yang Meng-Qi Wei Kai-Shan Tao 《World Journal of Clinical Cases》 SCIE 2024年第16期2847-2855,共9页
BACKGROUND The prognosis of hepatocellular carcinoma(HCC)combined with portal and hepatic vein cancerous thrombosis is poor,for unresectable patients the combination of targeted therapy and immune therapy was the firs... BACKGROUND The prognosis of hepatocellular carcinoma(HCC)combined with portal and hepatic vein cancerous thrombosis is poor,for unresectable patients the combination of targeted therapy and immune therapy was the first-line recommended treatment for advanced HCC,with a median survival time of only about 2.7-6 months.In this case report,we present the case of a patient with portal and hepatic vein cancerous thrombosis who achieved pathologic complete response after conversion therapy.CASE SUMMARY In our center,a patient with giant HCC combined with portal vein tumor thrombus and hepatic vein tumor thrombus was treated with transcatheter arterial chemoembolization(TACE),radiotherapy,targeted therapy and immunotherapy,and was continuously given icaritin soft capsules for oral regulation.After 7 months of conversion therapy,the patient's tumor shrank and the tumor thrombus subsided significantly.The pathology of surgical resection was in complete remission,and there was no progression in the postoperative follow-up for 7 months,which provided a basis for the future strategy of combined conversion therapy.CONCLUSION In this case,atezolizumab,bevacizumab,icaritin soft capsules combined with radiotherapy and TACE had a good effect.For patients with hepatocellular carcinoma combined with hepatic vein/inferior vena cava tumor thrombus,adopting a high-intensity,multimodal proactive strategy under the guidance of multidisciplinary team(MDT)is an important attempt to break through the current treatment dilemma. 展开更多
关键词 Hepatocellular carcinoma ICARITIN Conversion DOWNSTAGING Portal vein thrombus Case report
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铁山坡高含硫气藏安全快速钻井技术优化与应用
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作者 贺立勤 王军 +6 位作者 简旭 王雅萱 李晓刚 万夫磊 王华平 唐一元 邓开建 《钻采工艺》 CAS 北大核心 2024年第3期49-57,共9页
针对铁山坡气藏硫化氢含量高(最高达222.30 g/m^(3))、嘉五以上地层倾角大(最大倾角25°)、须家河组研磨性强、嘉陵江组高压盐水侵、飞仙关组地层压力系数低等难题,开展了套管柱、井口装置、钻具抗硫材质优选,优化了铁山坡区块的井... 针对铁山坡气藏硫化氢含量高(最高达222.30 g/m^(3))、嘉五以上地层倾角大(最大倾角25°)、须家河组研磨性强、嘉陵江组高压盐水侵、飞仙关组地层压力系数低等难题,开展了套管柱、井口装置、钻具抗硫材质优选,优化了铁山坡区块的井身结构,优选了高陡构造防斜提速工具,形成了铁山坡高含硫气藏安全快速钻井技术。现场应用效果表明,优选的抗硫钻具、套管柱、井口装置满足了高含硫气藏安全高效开发的要求;四开井身结构有效解决了上部地层井漏、垮塌、盐水侵的问题,降低了飞仙关高含硫层段的井控风险;优选了垂钻工具、钻头和旋导工具,铁山坡气田平均机械钻速由1.85 m/h提速到3.61 m/h,铁山坡6口井平均钻井周期缩短了16.11%。该研究成果为后续川东北高含硫气藏的安全快速钻井提供了技术支撑。 展开更多
关键词 铁山坡 高含硫化氢气藏 抗硫材质 防斜提速 溢漏同存
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光照、氮素对杂交水稻干物质积累、分配和产量形成的影响
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作者 潘胜才 陈余波 +2 位作者 简叙 卢沙沙 秦建权 《作物研究》 2024年第1期1-9,15,共10页
为了提高西南喀斯特山区的水稻产量,以Y两优900和宜香优2115为材料,采用裂区试验设计,设置花后遮光为主区因素(自然光照和遮光40%),氮肥为副区因素(90、180、270 kg/hm^(2)),研究光照、氮素及其互作对杂交水稻干物质积累、转运和产量形... 为了提高西南喀斯特山区的水稻产量,以Y两优900和宜香优2115为材料,采用裂区试验设计,设置花后遮光为主区因素(自然光照和遮光40%),氮肥为副区因素(90、180、270 kg/hm^(2)),研究光照、氮素及其互作对杂交水稻干物质积累、转运和产量形成的影响。结果表明:同一氮肥水平下,花后遮光40%可显著提高干物质转运量、转运率和贡献率,但也显著降低了花后干物质量、总干物质量、收获指数和结实率,最终导致水稻实际产量显著降低27.0%~31.3%。相同光照条件下,增施氮肥可显著提高有效穗数、单位面积总颖花数、干物质积累与转运量、收获指数和产量。在弱光条件下,增施氮肥能提高干物质转运量、转运率、贡献率和总颖花数,并且总干物质量、收获指数和结实率随着施氮量增多而提高,从而降低了花后弱光造成的产量损失。因此,在西南寡照区,适当增加氮肥的施用,扩大前期的群体和干物质积累量,能有效地补偿后期弱光造成的产量损失。 展开更多
关键词 水稻 光照 干物质积累 产量
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Cloud Top Pressure Retrieval Using Polarized and Oxygen A-band Measurements from GF5 and PARASOL Satellites
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作者 Lesi WEI Huazhe SHANG +6 位作者 jian xu Chong SHI Gegen TANA Kefu CHAO Shanhu BAO Liangfu CHEN Husi LETU 《Advances in Atmospheric Sciences》 SCIE CAS CSCD 2024年第4期680-700,共21页
Cloud top pressure(CTP)is one of the critical cloud properties that significantly affects the radiative effect of clouds.Multi-angle polarized sensors can employ polarized bands(490 nm)or O_(2)A-bands(763 and 765 nm)t... Cloud top pressure(CTP)is one of the critical cloud properties that significantly affects the radiative effect of clouds.Multi-angle polarized sensors can employ polarized bands(490 nm)or O_(2)A-bands(763 and 765 nm)to retrieve the CTP.However,the CTP retrieved by the two methods shows inconsistent results in certain cases,and large uncertainties in low and thin cloud retrievals,which may lead to challenges in subsequent applications.This study proposes a synergistic algorithm that considers both O_(2)A-bands and polarized bands using a random forest(RF)model.LiDAR CTP data are used as the true values and the polarized and non-polarized measurements are concatenated to train the RF model to determine CTP.Additionally,through analysis,we proposed that the polarized signal becomes saturated as the cloud optical thickness(COT)increases,necessitating a particular treatment for cases where COT<10 to improve the algorithm's stability.The synergistic method was then applied to the directional polarized camera(DPC)and Polarized and Directionality of the Earth’s Reflectance(POLDER)measurements for evaluation,and the resulting retrieval accuracy of the POLDER-based measurements(RMSEPOLDER=205.176 hPa,RMSEDPC=171.141 hPa,R^(2)POLDER=0.636,R^(2)DPC=0.663,respectively)were higher than that of the MODIS and POLDER Rayleigh pressure measurements.The synergistic algorithm also showed good performance with the application of DPC data.This algorithm is expected to provide data support for atmosphere-related fields as an atmospheric remote sensing algorithm within the Cloud Application for Remote Sensing,Atmospheric Radiation,and Updating Energy(CARE)platform. 展开更多
关键词 atmospheric remote sensing cloud top pressure multi-angle polarized O_(2)A-band GF-5/DPC PARASOL/POLDER-3
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Comparing the efficacy and safety of low,medium,and high dosages of selexipag for treating pulmonary hypertension:A systematic review and meta-analysis
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作者 Shang Wang Yi Yan +8 位作者 jian Zhang Ping Yuan Ci-Jun Luo Hong-Ling Qiu Hui-Ting Li jian xu Lan Wang Tian-Lan Li Rong jiang 《Animal Models and Experimental Medicine》 CAS CSCD 2024年第1期56-70,共15页
Background:The maintenance dosage of selexipag is categorized as low,medium or high.In order to assess the efficacy and safety of different dosages of selexipag for the risk stratification of pulmonary arterial hypert... Background:The maintenance dosage of selexipag is categorized as low,medium or high.In order to assess the efficacy and safety of different dosages of selexipag for the risk stratification of pulmonary arterial hypertension(PAH),we performed a sys-tematic review and meta-analysis.Methods:Studies assessing PAH risk stratification indices,such as the World Health Organization functional class(WHO-FC),six-minute walk distance(6MWD),N-terminal pro-B-type natriuretic peptide(NT-proBNP)level,right atrial pressure(RAP),cardiac index(CI)and mixed venous oxygen saturation(SvO2),were included.Results:Thirteen studies were included.Selexipag led to improvements in the 6MWD(MD:24.20 m,95%CI:10.74-37.67),NT-proBNP(SMD:-0.41,95%CI:-0.79-0.04),CI(MD:0.47 L/min/m^(2),95%CI:0.17-0.77)and WHO-FC(OR:0.564,95%CI:0.457-0.697).Subgroup analysis demonstrated that all three dosages improved the 6MWD.A moderate dosage led to improvements in the CI(MD:0.30 L/min/m^(2),95%CI:0.15-0.46)and WHO-FC(OR:0.589,95%CI:0.376-0.922).Within 6 months of treatment,only the WHO-FC and CI were significantly improved(OR:0.614,95%CI:0.380-0.993;MD:0.30 L/min/m^(2),95%CI:0.16-0.45,respectively).More than 6 months of treatment significantly improved the 6MWD,WHO-FC and NT-proBNP(MD:40.87 m,95%CI:10.97-70.77;OR:0.557,95%CI:0.440-0.705;SMD:-0.61,95%CI:-1.17-0.05,respectively).Conclusions:Low,medium,and high dosages of selexipag all exhibited good effects.When treatment lasted for more than 6 months,selexipag exerted obvious effects,even in the low-dosage group.This finding is important for guiding individualized treatments. 展开更多
关键词 individualized treatments META-ANALYSIS prostacyclin receptor agonist risk stratification systematic review
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Enhancing Log Anomaly Detection with Semantic Embedding and Integrated Neural Network Innovations
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作者 Zhanyang xu Zhe Wang +2 位作者 jian xu Hongyan Shi Hong Zhao 《Computers, Materials & Continua》 SCIE EI 2024年第9期3991-4015,共25页
System logs,serving as a pivotal data source for performance monitoring and anomaly detection,play an indispensable role in assuring service stability and reliability.Despite this,the majority of existing log-based an... System logs,serving as a pivotal data source for performance monitoring and anomaly detection,play an indispensable role in assuring service stability and reliability.Despite this,the majority of existing log-based anomaly detection methodologies predominantly depend on the sequence or quantity attributes of logs,utilizing solely a single Recurrent Neural Network(RNN)and its variant sequence models for detection.These approaches have not thoroughly exploited the semantic information embedded in logs,exhibit limited adaptability to novel logs,and a single model struggles to fully unearth the potential features within the log sequence.Addressing these challenges,this article proposes a hybrid architecture based on amultiscale convolutional neural network,efficient channel attention and mogrifier gated recurrent unit networks(LogCEM),which amalgamates multiple neural network technologies.Capitalizing on the superior performance of robustly optimized BERT approach(RoBERTa)in the realm of natural language processing,we employ RoBERTa to extract the original word vectors from each word in the log template.In conjunction with the enhanced Smooth Inverse Frequency(SIF)algorithm,we generate more precise log sentence vectors,thereby achieving an in-depth representation of log semantics.Subsequently,these log vector sequences are fed into a hybrid neural network,which fuses 1D Multi-Scale Convolutional Neural Network(MSCNN),Efficient Channel Attention Mechanism(ECA),and Mogrifier Gated Recurrent Unit(GRU).This amalgamation enables themodel to concurrently capture the local and global dependencies of the log sequence and autonomously learn the significance of different log sequences,thereby markedly enhancing the efficacy of log anomaly detection.To validate the effectiveness of the LogCEM model,we conducted evaluations on two authoritative open-source datasets.The experimental results demonstrate that LogCEM not only exhibits excellent accuracy and robustness,but also outperforms the current mainstream log anomaly detection methods. 展开更多
关键词 Deep learning log analysis anomaly detection natural language processing
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Left bundle branch area pacing combined with implantable cardioverter-defibrillator treatment for heart failure after myocardial infarction
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作者 Bing-Chen GUO jian xu +4 位作者 Yan-Zong LIU Guo-Qing DU Bo YU Shu-Feng LI Wen-Juan DU 《Journal of Geriatric Cardiology》 SCIE CAS CSCD 2024年第5期577-582,共6页
Left bundle branch area pacing(LBBAP)has emerged as a new physiological pacing mode.Previous studies have confirmed the feasibility and efficacy of LBBAP for cardiac resynchronization therapy(CRT)in heart failure(HF)p... Left bundle branch area pacing(LBBAP)has emerged as a new physiological pacing mode.Previous studies have confirmed the feasibility and efficacy of LBBAP for cardiac resynchronization therapy(CRT)in heart failure(HF)patients with left bundle branch block(LBBB)and a narrower QRS duration(QRSd)to have a higher percentage of super responders,and lower pacing thresholds than biventricular pacing(BiVP). 展开更多
关键词 PACING branch BUNDLE
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Uterine epithelioid trophoblastic tumor with the main manifestation of increased human chorionic gonadotropin:A case report
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作者 Li-Na Huang Xi Deng jian xu 《World Journal of Clinical Cases》 SCIE 2024年第16期2876-2880,共5页
BACKGROUND Epithelioid trophoblastic tumor(ETT)is an extremely rare malignant gestational trophoblastic neoplasm commonly presenting with abnormal vaginal bleeding,abdominal pain,and increased human chorionic gonadotr... BACKGROUND Epithelioid trophoblastic tumor(ETT)is an extremely rare malignant gestational trophoblastic neoplasm commonly presenting with abnormal vaginal bleeding,abdominal pain,and increased human chorionic gonadotropin(hCG).This study reported a case of uterine ETT with the main manifestation being increased hCG.CASE SUMMARY A 39-year-old female was referred to the Ningbo Maternal and Child Hospital of China in December 2022,complaining of increased hCG levels for 1 month.Magnetic resonance imaging revealed gestational trophoblastic tumor,and hysteroscopic electrotomy and curettage of intrauterine hyperplasia were performed.The patient was diagnosed with uterine ETT through postoperative pathological examination and immunohistochemical results.Total laparoscopic hysterectomy and bilateral salpingectomy were performed,and hCG levels returned to normal.The patient was without recurrence during the postoperative 3-month follow-up.CONCLUSION This study reported a case of uterine ETT with the main manifestation being increased hCG,highlighting that ETT should be considered in the presence of abnormal hCG.A total laparoscopic hysterectomy is recommended. 展开更多
关键词 Uterine epithelioid trophoblastic tumor Gestational trophoblastic neoplasm Diagnosis Human chorionic gonadotropin Case report
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Giant vascular malformations invading the skull:A case report
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作者 Ming-Chen Xie Fu-xu Wang jian xu 《World Journal of Clinical Cases》 SCIE 2024年第16期2869-2875,共7页
BACKGROUND Vascular malformations(VMs)arise as a result of errors in the process of angiogenesis and are usually present at birth,but may not become apparent until after birth.However,giant VMs of the head and face ar... BACKGROUND Vascular malformations(VMs)arise as a result of errors in the process of angiogenesis and are usually present at birth,but may not become apparent until after birth.However,giant VMs of the head and face are uncommon,with few reported cases,and the prognosis for their surgical intervention is unclear.CASE SUMMARY A 12-year-old girl was admitted to the hospital with findings of an enlarged right temporal scalp.After admission,computed tomography(CT)angiography of cerebral ateries showed a right occlusal gap and a right temporal artery venous malformation.Furthermore,cerebral angiography showed a right temporal lobe VM with multiple vessels supplying blood.The patient underwent surgery to remove the malformed vessels and the eroded skull.Two hours after the surgery,the patient's right pupil was dilated,and an urgent CT scan of the skull showed a right subdural haematoma under the incision,which was urgently removed by a second operation.After surgery,we gave continuous antibiotic anti-infection treatment,and the patient recovered well and was discharged two weeks later.CONCLUSION Surgical removal of giant haemangiomas is risky and adequate preoperative(including interventional embolisation)and intraoperative preparations should be made. 展开更多
关键词 Giant vascular malformation Early intervention Surgical intervention Interventional embolization Case report
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基于有限元法的含腐蚀缺陷钻杆剩余抗拉强度分析 被引量:1
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作者 万立夫 刘德平 +4 位作者 苏堪华 简旭 李猛 卓云 李昊 《重庆科技学院学报(自然科学版)》 CAS 2023年第5期1-7,共7页
基于有限元法研究含腐蚀缺陷钻杆的剩余抗拉强度问题,分别讨论轴向腐蚀长度、环向腐蚀长度、腐蚀深度、腐蚀半径等因素对钻杆剩余抗拉强度的影响。研究结果表明:对于均匀腐蚀缺陷钻杆,其剩余抗拉强度受腐蚀深度的影响最大,受环向腐蚀长... 基于有限元法研究含腐蚀缺陷钻杆的剩余抗拉强度问题,分别讨论轴向腐蚀长度、环向腐蚀长度、腐蚀深度、腐蚀半径等因素对钻杆剩余抗拉强度的影响。研究结果表明:对于均匀腐蚀缺陷钻杆,其剩余抗拉强度受腐蚀深度的影响最大,受环向腐蚀长度的影响次之,受轴向腐蚀长度的影响最小;对于点腐蚀缺陷钻杆,其剩余抗拉强度受腐蚀深度的影响最大,且随着腐蚀半径的增大而增大。与该有限元法相比,依据现行石油行业标准计算所得的钻杆剩余抗拉强度较大,按此强度设计的钻杆存在一定安全风险,因此,设计中应充分考虑不同腐蚀形态的影响。 展开更多
关键词 有限元分析 腐蚀缺陷 钻杆 剩余抗拉强度
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Effects of time-delayed vibration absorber on bandwidth of beam for low broadband vibration suppression 被引量:3
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作者 Xiuting SUN Yipeng QU +1 位作者 Feng WANG jian xu 《Applied Mathematics and Mechanics(English Edition)》 SCIE EI CSCD 2023年第10期1629-1650,共22页
The effects of time-delayed vibration absorber(TDVA) on the dynamic characteristics of a flexible beam are investigated. First, the vibration suppression effect of a single TDVA on a continuous beam is studied. The fi... The effects of time-delayed vibration absorber(TDVA) on the dynamic characteristics of a flexible beam are investigated. First, the vibration suppression effect of a single TDVA on a continuous beam is studied. The first optimization criterion is given,and the results show that the introduction of time-delayed feedback control(TDFC) is beneficial to improving the vibration suppression at the anti-resonance band. When a single TDVA is used, the anti-resonance is located at a specific frequency by the optimum design of TDFC parameters. Then, in order to obtain low-frequency and broad bands for vibration suppression, multiple TDVAs are uniformly distributed on a continuous beam,and the relationship between the dynamic responses and the TDFC parameters is investigated. The obtained relationship shows that the TDVA has a significant regulatory effect on the vibration behavior of the continuous beam. The effects of the number of TDVAs and the nonlinearity on the bandgap variation are discussed. As the multiple TDVAs are applied, according to the different requirements on the location and bandwidth of the effective vibration suppression band, the optimization criteria for the TDFC parameters are given, which provides guidance for the applications of TDVAs in practical projects such as bridge and aerospace. 展开更多
关键词 time-delayed vibration absorber(TDVA) time-delayed feedback control(TDFC) parameter design criterion broadband vibration suppression
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Three-dimensional isotropic microfabrication in glass using spatiotemporal focusing of high-repetition-rate femtosecond laser pulses 被引量:3
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作者 Yuanxin Tan Haotian Lv +10 位作者 jian xu Aodong Zhang Yunpeng Song jianping Yu Wei Chen Yuexin Wan Zhaoxiang Liu Zhaohui Liu Jia Qi Yangjian Cai Ya Cheng 《Opto-Electronic Advances》 SCIE EI CAS CSCD 2023年第10期18-29,共12页
To improve the processing efficiency and extend the tuning range of 3D isotropic fabrication,we apply the simultaneous spatiotemporal focusing(SSTF)technique to a high-repetition-rate femtosecond(fs)fiber laser system... To improve the processing efficiency and extend the tuning range of 3D isotropic fabrication,we apply the simultaneous spatiotemporal focusing(SSTF)technique to a high-repetition-rate femtosecond(fs)fiber laser system.In the SSTF scheme,we propose a pulse compensation scheme for the fiber laser with a narrow spectral bandwidth by building an extra-cavity pulse stretcher.We further demonstrate truly 3D isotropic microfabrication in photosensitive glass with a tunable resolution ranging from 8μm to 22μm using the SSTF of fs laser pulses.Moreover,we systematically investigate the influences of pulse energy,writing speed,processing depth,and spherical aberration on the fabrication resolution.As a proof-of-concept demonstration,the SSTF scheme was further employed for the fs laser-assisted etching of complicated glass microfluidic structures with 3D uniform sizes.The developed technique can be extended to many applications such as advanced photonics,3D biomimetic printing,micro-electromechanical systems,and lab-on-a-chips. 展开更多
关键词 simultaneous spatiotemporal focusing technique pulse compensation pulse stretcher 3D isotropic fabrication chemical etching
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Treatment of stellate ganglion block in diseases:Its role and application prospect 被引量:3
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作者 Jing-Jing Deng Cai-Ling Zhang +4 位作者 Dian-Wen Liu Tao Huang jian xu Qing-Yan Liu Yue-Nong Zhang 《World Journal of Clinical Cases》 SCIE 2023年第10期2160-2167,共8页
The stellate ganglion(SG),as a type of sympathetic ganglion,consists of the sixth and seventh cervical vertebrae and the first thoracic sympathetic ganglia.SG block(SGB)is a minimally invasive injection that aims to i... The stellate ganglion(SG),as a type of sympathetic ganglion,consists of the sixth and seventh cervical vertebrae and the first thoracic sympathetic ganglia.SG block(SGB)is a minimally invasive injection that aims to inject low-concentration local anesthetics to induce a broad sympathetic blocking effect near the SG.There have been no changes and progress in the clinical application of SGB since the 1830s due to several potential risks,including hematoma from blood vessel injury,hoarseness from recurrent laryngeal nerve injury,and cardiopulmonary arrest.The feasibility and safety of SGB have greatly improved since the appearance of ultrasound-guided SGB.In recent years,SGB has been widely applied in the field of non-anesthesiology sedation,with significant therapeutic effects on pain,immunological diseases,somnipathy,psychological disorders,arrhythmias,and endocrine diseases.The present study reviews the present application of SGB in clinical practice. 展开更多
关键词 ECHOCARDIOGRAPHY PAIN Immunological diseases Somnipathy Psychological disorders ARRHYTHMIAS Endocrine diseases
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Study on Real-Time Heart Rate Detection Based on Multi-People 被引量:2
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作者 Qiuyu Hu Wu Zeng +3 位作者 Yi Sheng jian xu Weihua Ou Ruochen Tan 《Computer Systems Science & Engineering》 SCIE EI 2023年第2期1397-1408,共12页
Heart rate is an important vital characteristic which indicates physical and mental health status.Typically heart rate measurement instruments require direct contact with the skin which is time-consuming and costly.Th... Heart rate is an important vital characteristic which indicates physical and mental health status.Typically heart rate measurement instruments require direct contact with the skin which is time-consuming and costly.Therefore,the study of non-contact heart rate measurement methods is of great importance.Based on the principles of photoelectric volumetric tracing,we use a computer device and camera to capture facial images,accurately detect face regions,and to detect multiple facial images using a multi-target tracking algorithm.Then after the regional segmentation of the facial image,the signal acquisition of the region of interest is further resolved.Finally,frequency detection of the collected Photo-plethysmography(PPG)and Electrocardiography(ECG)signals is completed with peak detection,Fourier analysis,and a Waveletfilter.The experimental results show that the subject’s heart rate can be detected quickly and accurately even when monitoring multiple facial targets simultaneously. 展开更多
关键词 Face recognition face analysis heart rate detection IPPG signal
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Screening effect of plasma flow on the resonant magnetic perturbation penetration in tokamaks based on two-fluid model
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作者 汤炜康 栾其斌 +5 位作者 孙宏恩 魏来 路爽爽 姜帅 徐健 王正汹 《Plasma Science and Technology》 SCIE EI CAS CSCD 2023年第4期23-32,共10页
Numerical simulation on the resonant magnetic perturbation penetration is carried out by the newly-updated initial value code MDC(MHD@Dalian Code).Based on a set of two-fluid fourfield equations,the bootstrap current,... Numerical simulation on the resonant magnetic perturbation penetration is carried out by the newly-updated initial value code MDC(MHD@Dalian Code).Based on a set of two-fluid fourfield equations,the bootstrap current,parallel,and perpendicular transport effects are included appropriately.Taking into account the bootstrap current,a mode penetration-like phenomenon is found,which is essentially different from the classical tearing mode model.To reveal the influence of the plasma flow on the mode penetration process,E×B drift flow and diamagnetic drift flow are separately applied to compare their effects.Numerical results show that a sufficiently large diamagnetic drift flow can drive a strong stabilizing effect on the neoclassical tearing mode.Furthermore,an oscillation phenomenon of island width is discovered.By analyzing it in depth,it is found that this oscillation phenomenon is due to the negative feedback regulation of pressure on the magnetic island.This physical mechanism is verified again by key parameter scanning. 展开更多
关键词 TOKAMAK TWO-FLUID NTM
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Outsourced Privacy-Preserving kNN Classifier Model Based on Multi-Key Homomorphic Encryption
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作者 Chen Wang jian xu +2 位作者 Jiarun Li Yan Dong Nitin Naik 《Intelligent Automation & Soft Computing》 SCIE 2023年第8期1421-1436,共16页
Outsourcing the k-Nearest Neighbor(kNN)classifier to the cloud is useful,yet it will lead to serious privacy leakage due to sensitive outsourced data and models.In this paper,we design,implement and evaluate a new sys... Outsourcing the k-Nearest Neighbor(kNN)classifier to the cloud is useful,yet it will lead to serious privacy leakage due to sensitive outsourced data and models.In this paper,we design,implement and evaluate a new system employing an outsourced privacy-preserving kNN Classifier Model based on Multi-Key Homomorphic Encryption(kNNCM-MKHE).We firstly propose a security protocol based on Multi-key Brakerski-Gentry-Vaikuntanathan(BGV)for collaborative evaluation of the kNN classifier provided by multiple model owners.Analyze the operations of kNN and extract basic operations,such as addition,multiplication,and comparison.It supports the computation of encrypted data with different public keys.At the same time,we further design a new scheme that outsources evaluation works to a third-party evaluator who should not have access to the models and data.In the evaluation process,each model owner encrypts the model and uploads the encrypted models to the evaluator.After receiving encrypted the kNN classifier and the user’s inputs,the evaluator calculated the aggregated results.The evaluator will perform a secure computing protocol to aggregate the number of each class label.Then,it sends the class labels with their associated counts to the user.Each model owner and user encrypt the result together.No information will be disclosed to the evaluator.The experimental results show that our new system can securely allow multiple model owners to delegate the evaluation of kNN classifier. 展开更多
关键词 Outsourced privacy-preserving multi-key HE machine learning KNN
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Impact of angiotensin-converting enzyme inhibitors or angiotensin receptor blockers on the mortality in sepsis: A meta-analysis
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作者 Deng-Can Yang jian xu +1 位作者 Li jian Yi Yu 《World Journal of Clinical Cases》 SCIE 2023年第36期8498-8506,共9页
BACKGROUND The effect of angiotensin-converting enzyme inhibitors(ACEIs)or angiotensin receptor blockers(ARBs)on the mortality of patients with sepsis is not well characterized.AIM To elucidate the association between... BACKGROUND The effect of angiotensin-converting enzyme inhibitors(ACEIs)or angiotensin receptor blockers(ARBs)on the mortality of patients with sepsis is not well characterized.AIM To elucidate the association between prior ACEI or ARB exposure and mortality in sepsis.METHODS The PubMed,EMBASE,Web of Science,and Cochrane Library databases were searched for all studies of premorbid ACEI or ARB use and sepsis mortality until November 302019.Two reviewers independently assessed,selected,and ab-stracted data from studies reporting ACEIs or ARBs,sepsis,and mortality.The primary extracted data consisted of premorbid ACEI or ARB exposure,mortality,and general patient data.Two reviewers independently assessed the risk of bias and quality of evidence.RESULTS A total of six studies comprising 281238 patients with sepsis,including 49799 cases with premorbid ACEI or ARB exposure were eligible for analysis.Pre-morbid ACEIs or ARBs exposure decreased the 30-d mortality in patients with sepsis.Moreover,the use of ACEIs or ARBs was associated with approximately a 6%decreased risk of 30-d mortality.CONCLUSION The results of this systematic review suggest that ACEI or ARB exposure prior to sepsis may be associated with reduced mortality.Further high-quality cohort studies and molecular mechanism experiments are required to confirm our results. 展开更多
关键词 SEPSIS MORTALITY Angiotensin-converting enzyme inhibitors Angiotensin receptor blockers
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