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1.5μm Self-Aligned Spotsize Converter Integrated DFB Fabricated by Selective Area Grown MOVPE
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作者 邱伟彬 董杰 +1 位作者 王圩 周帆 《Journal of Semiconductors》 EI CAS CSCD 北大核心 2002年第7期681-684,共4页
High performance 1 57μm spotsize converter monolithically integrated DFB is fabricated by the technique of self aligned selective area growth.The upper optical confinement layer and the butt coupled tapered thickn... High performance 1 57μm spotsize converter monolithically integrated DFB is fabricated by the technique of self aligned selective area growth.The upper optical confinement layer and the butt coupled tapered thickness waveguide are regrown simultaneously,which not only offeres the separated optimization of the active region and the integrated spotsize converter,but also reduces the difficulty of the butt joint selective regrowth.The threshold current is as low as 4 4mA.The output power at 49mA is 10 1mW.The side mode suppression ratio (SMSR) is 33 2dB.The vertical and horizontal far field divergence angles are as small as 9° and 15° respectively,the 1dB misalignment tolerance are 3 6μm and 3 4μm. 展开更多
关键词 spotsize converter self aligned butt joint selective area growth
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基于Self-Attention-BiLSTM网络的西瓜种苗叶片氮磷钾含量高光谱检测方法
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作者 徐胜勇 刘政义 +3 位作者 黄远 曾雨 别之龙 董万静 《农业机械学报》 EI CAS CSCD 北大核心 2024年第8期243-252,共10页
元素含量无损检测技术可以为植物生长发育的环境精准调控提供关键实时数据。以西瓜苗为例,提出了一种基于图谱特征融合的氮磷钾含量深度学习检测方法。首先,使用高光谱仪拍摄西瓜苗叶片的高光谱图像,使用连续流动化学分析仪测定叶片的3... 元素含量无损检测技术可以为植物生长发育的环境精准调控提供关键实时数据。以西瓜苗为例,提出了一种基于图谱特征融合的氮磷钾含量深度学习检测方法。首先,使用高光谱仪拍摄西瓜苗叶片的高光谱图像,使用连续流动化学分析仪测定叶片的3种元素含量。然后,采用基线偏移校正(BOC)叠加高斯平滑滤波(GF)的光谱预处理方法和随机森林算法(RF)建立预测模型,基于竞争性自适应重加权采样(CARS)和连续投影算法(SPA)2种算法初步筛选出特征波长,再综合考虑波长数和建模精度设计了一种最优波长评价方法,将波长数进一步减少到3~4个。最后,提取使用U-Net网络分割的彩色图像颜色和纹理特征,和光谱反射率特征一起作为输入,基于自注意力机制-双向长短时记忆(Self-Attention-BiLSTM)网络构建了3种元素含量的预测模型。实验结果表明,氮磷钾含量预测的R2分别为0.961、0.954、0.958,RMSE分别为0.294%、0.262%、0.196%,实现了很好的建模效果。使用该模型对另2个品种西瓜进行测试,R2超过0.899、RMSE小于0.498%,表明该模型具有很好的泛化性。该高光谱建模方法使用少量波长光谱即实现了高精度检测,在精度和效率上达成了很好的平衡,为后续便携式高光谱检测装备开发奠定了理论基础。 展开更多
关键词 西瓜苗叶片 元素含量 无损检测 自注意力机制 双向长短时记忆网络 高光谱
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Self-Healable and Stretchable PAAc/XG/Bi_(2)Se_(0.3)Te_(2.7) Hybrid Hydrogel Thermoelectric Materials
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作者 Jinmeng Li Tian Xu +7 位作者 Zheng Ma Wang Li Yongxin Qian Yang Tao Yinchao Wei Qinghui Jiang Yubo Luo Junyou Yang 《Energy & Environmental Materials》 SCIE EI CAS CSCD 2024年第2期180-186,共7页
Thermoelectric power generators have attracted increasing interest in recent years owing to their great potential in wearable electronics power supply.It is noted that thermoelectric power generators are easy to damag... Thermoelectric power generators have attracted increasing interest in recent years owing to their great potential in wearable electronics power supply.It is noted that thermoelectric power generators are easy to damage in the dynamic service process,resulting in the formation of microcracks and performance degradation.Herein,we prepare a new hybrid hydrogel thermoelectric material PAAc/XG/Bi_(2)Se_(0.3)Te_(2.7)by an in situ polymerization method,which shows a high stretchable and self-healable performance,as well as a good thermoelectric performance.For the sample with Bi_(2)Se_(0.3)Te_(2.7)content of 1.5 wt%(i.e.,PAAc/XG/Bi2Se0.3Te27(1.5 wt%)),which has a room temperature Seebeck coefficient of-0.45 mV K^(-1),and exhibits an open-circuit voltage of-17.91 mV and output power of 38.1 nW at a temperature difference of 40 K.After being completely cut off,the hybrid thermoelectric hydrogel automatically recovers its electrical characteristics within a response time of 2.0 s,and the healed hydrogel remains more than 99%of its initial power output.Such stretchable and self-healable hybrid hydrogel thermoelectric materials show promising potential for application in dynamic service conditions,such as wearable electronics. 展开更多
关键词 bismuth telluride self healing thermoelectric material
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Enhanced performance of a solar cell based on a layer-by-layer self-assembled luminescence down-shifting layer of core–shell quantum dots 被引量:1
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作者 Ni Liu Shu-Xin Li +1 位作者 Ying-Chun Ye Yan-Li Yao 《Chinese Physics B》 SCIE EI CAS CSCD 2018年第12期461-465,共5页
In this paper, core–shell quantum dots(QDs) with two polar surface functional groups(ZnSe/ZnS–COOH QDs and ZnSe/ZnS–NH_2 QDs) are synthesized in an aqueous phase. Photoluminescence(PL) and absorption spectra clearl... In this paper, core–shell quantum dots(QDs) with two polar surface functional groups(ZnSe/ZnS–COOH QDs and ZnSe/ZnS–NH_2 QDs) are synthesized in an aqueous phase. Photoluminescence(PL) and absorption spectra clearly indicate luminescence down-shifting(LDS) properties. On the basis of QDs, surface functional group multilayer LDS films(MLDSs) are fabricated through an electrostatic layer-by-layer(LBL) self-assembly method. The PL intensity increases linearly with the number of bilayers, showing a regular and uniform film growth. When the M-LDS is placed on the surface of a Si-based solar cell as an optical conversion layer for the first time, the external quantum efficiency(EQE) and shortcircuit current density(Jsc) notably increases for the LDS process. The EQE response improves in a wavelength region extending from the UV region to the blue region, and its maximum increase reaches more than 15% between 350 nm and 460 nm. 展开更多
关键词 two-surface functional group LBL self-assembly LDS
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RepBoTNet-CESA:An Alzheimer’s Disease Computer Aided Diagnosis Method Using Structural Reparameterization BoTNet and Cubic Embedding Self Attention
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作者 Xiabin Zhang Zhongyi Hu +1 位作者 Lei Xiao Hui Huang 《Computers, Materials & Continua》 SCIE EI 2024年第5期2879-2905,共27页
Various deep learning models have been proposed for the accurate assisted diagnosis of early-stage Alzheimer’s disease(AD).Most studies predominantly employ Convolutional Neural Networks(CNNs),which focus solely on l... Various deep learning models have been proposed for the accurate assisted diagnosis of early-stage Alzheimer’s disease(AD).Most studies predominantly employ Convolutional Neural Networks(CNNs),which focus solely on local features,thus encountering difficulties in handling global features.In contrast to natural images,Structural Magnetic Resonance Imaging(sMRI)images exhibit a higher number of channel dimensions.However,during the Position Embedding stage ofMulti Head Self Attention(MHSA),the coded information related to the channel dimension is disregarded.To tackle these issues,we propose theRepBoTNet-CESA network,an advanced AD-aided diagnostic model that is capable of learning local and global features simultaneously.It combines the advantages of CNN networks in capturing local information and Transformer networks in integrating global information,reducing computational costs while achieving excellent classification performance.Moreover,it uses the Cubic Embedding Self Attention(CESA)proposed in this paper to incorporate the channel code information,enhancing the classification performance within the Transformer structure.Finally,the RepBoTNet-CESA performs well in various AD-aided diagnosis tasks,with an accuracy of 96.58%,precision of 97.26%,and recall of 96.23%in the AD/NC task;an accuracy of 92.75%,precision of 92.84%,and recall of 93.18%in the EMCI/NC task;and an accuracy of 80.97%,precision of 83.86%,and recall of 80.91%in the AD/EMCI/LMCI/NC task.This demonstrates that RepBoTNet-CESA delivers outstanding outcomes in various AD-aided diagnostic tasks.Furthermore,our study has shown that MHSA exhibits superior performance compared to conventional attention mechanisms in enhancing ResNet performance.Besides,the Deeper RepBoTNet-CESA network fails to make further progress in AD-aided diagnostic tasks. 展开更多
关键词 Alzheimer CNN structural reparameterization multi head self attention computer aided diagnosis
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Unified Description of the Three Stable Particles in Self-Action Allows Determination of Their Relative Masses
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作者 Yair Goldin Halfon 《Journal of High Energy Physics, Gravitation and Cosmology》 CAS 2024年第1期185-196,共12页
The Dirac equation γ<sub>μ</sub>(δ<sub>μ</sub>-eA<sub>μ</sub>)Ψ=mc<sup>2</sup>Ψ describes the bound states of the electron under the action of external potentials... The Dirac equation γ<sub>μ</sub>(δ<sub>μ</sub>-eA<sub>μ</sub>)Ψ=mc<sup>2</sup>Ψ describes the bound states of the electron under the action of external potentials, A<sub>μ</sub>. We assumed that the fundamental form of the Dirac equation γ<sub>μ</sub>(δ<sub>μ</sub>-S<sub>μ</sub>)Ψ=0 should describe the stable particles (the electron, the proton and the dark-matter-particle (dmp)) bound to themselves under the action of their own potentials S<sub>μ</sub>. The new equation reveals that self energy is consequence of self action, it also reveals that the spin angular momentum is consequence of the dynamic structure of the stable particles. The quantitative results are the determination of their relative masses as well as the determination of the electromagnetic coupling constant. 展开更多
关键词 Electron in self Action Electron-Dark-Matter Particle Mass Ratio Analytic Description Dark-Matter-Particle
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Adaptive Surrogate Model Based Optimization (ASMBO) for Unknown Groundwater Contaminant Source Characterizations Using Self-Organizing Maps 被引量:2
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作者 Shahrbanoo Hazrati-Yadkoori Bithin Datta 《Journal of Water Resource and Protection》 2017年第2期193-214,共22页
Characterization of unknown groundwater contaminant sources in terms of location, magnitude and duration of source activity is a complex problem. In this study, to increase the efficiency and accuracy of source charac... Characterization of unknown groundwater contaminant sources in terms of location, magnitude and duration of source activity is a complex problem. In this study, to increase the efficiency and accuracy of source characterization an alternative methodology to the methodologies proposed earlier is developed. This methodology, Adaptive Surrogate Modeling Based Optimization (ASMBO) uses the capabilities of Self Organizing Map (SOM) algorithm to design the surrogate models and adaptive surrogate models for source characterization. The most important advantage of this methodology is its direct utilization for groundwater contaminant characterization without the necessity of utilizing a linked simulation optimization model. The validation of the SOM based surrogate models and SOM based adaptive surrogate models demonstrates that the quantity and quality of initial sample sizes have crucial role on the accuracy of solutions as the designed monitoring locations. The performance evaluation results of the proposed methodology are obtained using error free and erroneous concentration measurement data. These results demonstrate that the developed methodology could approximate groundwater flow and transport simulation models, and substitute the optimization model for characterization of unknown groundwater contaminant sources in terms of location, magnitude and duration of source activity. 展开更多
关键词 self-ORGANIZING Map Surrogate MODELS ADAPTIVE Surrogate MODELS GROUNDWATER Contamination Source Identification
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Huge brown tumor of the rib in an unlocatable hyperparathyroidism patient with “self-recovered” serum calcium and parathyroid hormone: A case report 被引量:1
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作者 Wen-Da Wang Ning Zhang +1 位作者 Qiang Qu Xiao-Dong He 《World Journal of Clinical Cases》 SCIE 2019年第24期4321-4326,共6页
BACKGROUND The brown tumor is a kind of complication of hyperparathyroidism(HPT). The ultimate therapy usually is the resolution of HPT. We herein report an unlocatable HPT patient who received resection of a huge bro... BACKGROUND The brown tumor is a kind of complication of hyperparathyroidism(HPT). The ultimate therapy usually is the resolution of HPT. We herein report an unlocatable HPT patient who received resection of a huge brown tumor of the rib, and experienced "self-recovery" of serum calcium and parathyroid hormone.CASE SUMMARY A 34-year-old female patient who suffered from a gradually increasing mass of the left chest wall since 2007 came to our hospital for treatment. The patient had a history of serum Ca and parathyroid hormone(PTH) increasing since June 2015 and received zoledronic acid treatment for 17 mo. When she came to our hospital in November 2017 after discontinuing medical treatment for 3 mo, the serum Ca and PTH levels were within normal ranges. The patient had no imaging abnormalities of parathyroid ultrasound or 99 m Tc-methoxyisobutyl isonitrile.Enhanced computed tomography revealed a local soft tissue mass of 96 mm × 113 mm with bone erosion of the left 8 th rib, and the mass presented irregular enhancement with an unclear boundary between the mass and spleen. The mass was thought to likely be caused by HPT, but a malignancy could not be ruled out.Resection of the mass was performed, and the pathology proved that the mass was a brown tumor. A diagnosis of unlocatable HPT was considered. Since the serum Ca and PTH levels were both normal pre-and post-operation, the patient did not receive exploratory surgery for HPT, and received regular follow-up.CONCLUSION The huge brown tumor of the rib and "self-recovered" serum PTH and Ca levels are relatively rare in HPT patients. An exploratory operation may be deferred for these patients, and long-term follow-up should be performed. 展开更多
关键词 Brown tumor HYPERPARATHYROIDISM Unlocatable self-recovered RESECTION Case report
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Safety and efficacy of Kaffes intraductal self-expanding metal stents in the management of post-liver transplant anastomotic strictures
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作者 Chee Lim Jonathan Ng +4 位作者 Babak Sarraf Rhys Vaughan Marios Efthymiou Leonardo Zorron Cheng Tao Pu Sujievvan Chandran 《World Journal of Transplantation》 2024年第2期88-98,共11页
BACKGROUND Endoscopic management is the first-line therapy for post-liver-transplant anas-tomotic strictures.Although the optimal duration of treatment with plastic stents has been reported to be 8-12 months,data on s... BACKGROUND Endoscopic management is the first-line therapy for post-liver-transplant anas-tomotic strictures.Although the optimal duration of treatment with plastic stents has been reported to be 8-12 months,data on safety and duration for metal stents in this setting is scarce.Due to limited access to endoscopic retrograde cholan-giopancreatography(ERCP)during the coronavirus disease 2019 pandemic in our centre,there was a change in practice towards increased usage and length-of-stay of the Kaffes biliary intraductal self-expanding stent in patients with suitable anatomy.This was mainly due to the theoretical benefit of Kaffes stents allowing for longer indwelling periods compared to the traditional plastic stents.METHODS Adult liver transplant recipients aged 18 years and above who underwent ERCP were retrospectively identified during a 10-year period through a database query.Unplanned admissions post-Kaffes stent insertion were identified manually through electronic and scanned medical records.The main outcome was the incidence of complications when stents were left indwelling for 3 months vs 6 months.Stent efficacy was calculated via rates of stricture recurrence between patients that had stenting courses for≤120 d or>120 d.RESULTS During the study period,a total of 66 ERCPs with Kaffes insertion were performed in 54 patients throughout their stenting course.In 33 ERCPs,the stent was removed or exchanged on a 3-month interval.No pancreatitis,perfor-ations or deaths occurred.Minor post-ERCP complications were similar between the 3-month(abdominal pain and intraductal migration)and 6-month(abdominal pain,septic shower and embedded stent)groups-6.1%vs 9.1%respectively,P=0.40.All strictures resolved at the end of the stenting course,but the stenting course was variable from 3 to 22 months.The recurrence rate for stenting courses lasting for up to 120 d was 71.4%and 21.4%for stenting courses of 121 d or over(P=0.03).There were 28 patients that were treated with a single ERCP with Kaffes,21 with removal after 120 d and 7 within 120 d.There was a significant improvement in stricture recurrence when the Kaffes was removed after 120 d when a single ERCP was used for the entire stenting course(71.0%vs 10.0%,P=0.01).CONCLUSION Utilising a single Kaffes intraductal fully-covered metal stent for at least 4 months is safe and efficacious for the management of post-transplant anastomotic strictures. 展开更多
关键词 Liver transplantation CHOLANGIOPANCREATOGRAPHY Endoscopic retrograde CONSTRICTION PATHOLOGIC self expandable metallic stents Bile duct diseases CHOLESTASIS
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Study on the Cultivation of the Mycardium and Myocardium Self-disciplining Cell Mass of Mouse Embryonic Bodies with their Own Feeder Layer
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作者 LIU Yan ZHANG Gui-xue CAO Yun-kao 《Journal of Northeast Agricultural University(English Edition)》 CAS 2003年第2期131-136,共6页
Myocardium tissue of Kunming mouse embryonic bodies was cultured with the feeder layer of their embryonic fibroblasts in TCM199.The results indicate that some piece of myocardium tissue can be cultured in the feeder l... Myocardium tissue of Kunming mouse embryonic bodies was cultured with the feeder layer of their embryonic fibroblasts in TCM199.The results indicate that some piece of myocardium tissue can be cultured in the feeder layer;Their contracting frequency changed with the temperature and the morphology changed with the time;It was not all pieces of tissue with the same appearance that could contract,even though some of them grow well. 展开更多
关键词 MYOCARDIUM feeder layer mouse self-disciplining
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Synthesis of Crown Ether-tethered b-Cyclodextrin and Fabrication of Its Self-assembled Monolayer on Gold Surface
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作者 Yu LIU Shi Zhao KANG Chun Hua DIAO 《Chinese Chemical Letters》 SCIE CAS CSCD 2001年第10期891-892,共2页
A novel b-cyclodextrin derivative 6 bearing a crown ether moiety has been synthesized by a convenient method in 9.4% yield. Its self-assembled monolayer (SAM) was fabricated on the gold surface, which was characteriz... A novel b-cyclodextrin derivative 6 bearing a crown ether moiety has been synthesized by a convenient method in 9.4% yield. Its self-assembled monolayer (SAM) was fabricated on the gold surface, which was characterized by using surface-enhanced Raman spectra. 展开更多
关键词 Cyclodextrin derivative crown ether self-assembled monolayer.
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惠特曼诗歌“One's-Self I Sing”译法之我见
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作者 李红梅 《承德民族师专学报》 2003年第4期85-88,共4页
通过对惠特曼诗的两种译文的比较和评论,希望能够更加充分地体现原诗的"自由与民主"主题和"有节奏、无韵律"的风格,使用更简短、准确的措辞,尾韵和排比的方法,使新的译文更加准确、生动、流畅、自然。
关键词 英诗新译 民主 大众 人本身 现代人
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Survey on the Amount of Physical Activity and Self-Esteem of School Age Students in A Town in Japan
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作者 Ayako Ohgino Yumiko Nakamura Kahara Yukie 《Health》 2022年第1期46-56,共11页
This study aimed to clarify the amount of physical activity, lifestyle, and self-esteem of elementary school students living in Aomori Prefecture Japan. The subjects were ninety-one elementary school students in the 4... This study aimed to clarify the amount of physical activity, lifestyle, and self-esteem of elementary school students living in Aomori Prefecture Japan. The subjects were ninety-one elementary school students in the 4th to 6th grades who live in A town. The subjects were asked to fill out a questionnaire about lifestyles and self-esteem and to wear the lifestyle-related recorder Life Coder GS<span style="white-space:nowrap;"><span style="white-space:nowrap;"><sup>&#174;</sup></span></span> (Suzuken, Japan) for a total of four days, two weekdays and two holidays. The results showed the amount of exercise such as the number of steps taken was significantly higher on weekdays than on holidays. There was no difference by gender or classification of obesity. In addition, when they go to school on foot, the number of steps and fast walking time was significantly higher than when using the bus. Screen times of holidays were significantly longer than those of weekdays. The number of steps on holidays was negatively correlated with screen time, and positively correlated with the factor of “self-assertion/self-determination” of self-esteem scale. Health promotion is needed so that the entire community, including family and friends, can develop daily physical activities. 展开更多
关键词 Physical Activity Children EXERCISE self-ESTEEM
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ConvNeXt网络及Stacked BiLSTM-Self-Attention在轴承剩余寿命预测中的应用
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作者 张印文 王琳霖 +1 位作者 薛文科 梁文婕 《机电工程》 CAS 北大核心 2024年第11期1977-1985,1994,共10页
在滚动轴承剩余使用寿命预测方面,采用传统方法时存在鲁棒性差、精度低等各种问题。近些年来深度学习的发展为解决这些问题提供了新的思路。为了进一步提高对轴承寿命的预测精度,提出了一种基于ConvNeXt网络、堆叠双向长短时记忆网络(SB... 在滚动轴承剩余使用寿命预测方面,采用传统方法时存在鲁棒性差、精度低等各种问题。近些年来深度学习的发展为解决这些问题提供了新的思路。为了进一步提高对轴承寿命的预测精度,提出了一种基于ConvNeXt网络、堆叠双向长短时记忆网络(SBiLSTM)和自注意力机制(Self-Attention)的滚动轴承寿命预测方法。首先,采用连续小波变换(CWT)构造了振动信号的时频图,以更好地捕捉信号的时域和频域特征;然后,将得到的时频图输入到构建的ConvNeXt网络中,通过卷积、池化和层归一化等操作,对时频图的关键特征进行了提取;最后,将提取后的特征输入到SBiLSTM-Self-Attention模块中,进一步提取了时序信息和特征权重分配数据,利用PHM2012挑战数据集进行了验证,通过实验分析了该方法的均方根误差(RMSE)和平均绝对误差(MAE)。研究结果表明:相较于现有技术方法,该方法的平均RMSE为0.031;与其他三种方法,即卷积神经网络(CNN)、深度残差双向门控循环单元(DRN-BiGRU)和深度卷积自注意力双向门控循环单元(DCNN-Self-Attention-BiGRU)相比,其平均RMSE值分别下降了79%、74%和55%,MAE值分别下降了78%、73%和53%,说明该方法在滚动轴承剩余寿命预测中有较好的性能。 展开更多
关键词 滚动轴承 剩余寿命预测 ConvNeXt网络 堆叠双向长短时记忆网络 自注意力机制 深度学习 连续小波变换
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Perception of One's Own and Another's Behaviors Related to Morality Does Self-accuracy Matter?
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作者 Hanna Brycz 《Psychology Research》 2011年第6期422-443,共22页
关键词 以德治国 人的行为 精度 TRAP 观察者 评估 负荷
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Consistency of intensity ratio between spectral lines with similar self-absorption characteristics during ungated laser induced breakdown spectroscopy measurements
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作者 Jung-Hwan IN Youngmin MOON +1 位作者 Jang-Hee CHOI Sungho JEONG 《Plasma Science and Technology》 SCIE EI CAS CSCD 2019年第3期77-83,共7页
This work reports that the intensity ratio of spectral lines having similar self-absorption characteristics during laser induced breakdown spectroscopy(LIBS) analysis can become nearly constant over a wide range of ir... This work reports that the intensity ratio of spectral lines having similar self-absorption characteristics during laser induced breakdown spectroscopy(LIBS) analysis can become nearly constant over a wide range of irradiation conditions if the intensities are integrated over a sufficiently long time. It is shown that the plasma temperature and intensity ratio of these spectral lines have temporal similarity. The spectral lines with similar self-absorption properties may be selected to improve the accuracy and consistency of LIBS analysis results under an environment with fluctuating measurement conditions. 展开更多
关键词 laser induced BREAKDown spectroscopy INTENSITY ratio self-ABSORPTION CHARACTERISTICS CIGS solar cell
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Influence of self-heating on the millimeter-wave and terahertz performance of MBE grown silicon IMPATT diodes
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作者 S.J.Mukhopadhyay Prajukta Mukherjee +1 位作者 Aritra Acharyya Monojit Mitra 《Journal of Semiconductors》 EI CAS CSCD 2020年第3期13-22,共10页
The influence of self-heating on the millimeter-wave(mm-wave)and terahertz(THz)performance of double-drift region(DDR)impact avalanche transit time(IMPATT)sources based on silicon(Si)has been investigated in this pape... The influence of self-heating on the millimeter-wave(mm-wave)and terahertz(THz)performance of double-drift region(DDR)impact avalanche transit time(IMPATT)sources based on silicon(Si)has been investigated in this paper.The dependences of static and large-signal parameters on junction temperature are estimated using a non-sinusoidal voltage excited(NSVE)large-signal simulation technique developed by the authors,which is based on the quantum-corrected drift-diffusion(QCDD)model.Linear variations of static parameters and non-linear variations of large-signal parameters with temperature have been observed.Analytical expressions representing the temperature dependences of static and large-signal parameters of the diodes are developed using linear and 2nd degree polynomial curve fitting techniques,which will be highly useful for optimizing the thermal design of the oscillators.Finally,the simulated results are found to be in close agreement with the experimentally measured data. 展开更多
关键词 IMPATT oscillators linear temperature coefficient self-HEATING thermal runway quadratic temperature coefficient
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Self-Encoded Multiple Access Multiuser Convolutional Codes in Uplink and Downlink Cellular Systems
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作者 Jong Hak JUNG Won Mee JANG Lim NGUYEN 《International Journal of Communications, Network and System Sciences》 2009年第4期249-257,共9页
Self-encoded spread spectrum eliminates the need for traditional pseudo noise (PN) code generators. In a self-encoded multiple access (SEMA) system, the number of users is not limited by the number of available sequen... Self-encoded spread spectrum eliminates the need for traditional pseudo noise (PN) code generators. In a self-encoded multiple access (SEMA) system, the number of users is not limited by the number of available sequences, unlike code division multiple access (CDMA) systems that employ PN codes such as m-, Gold or Kassami sequences. SEMA provides a convenient way of supporting multi-rate, multi-level grades of service in multimedia communications and prioritized heterogeneous networking systems. In this paper, we propose multiuser convolutional channel coding in SEMA that provides fewer cross-correlations among users and thereby reducing multiple access interference (MAI). We analyze SEMA multiuser convolutional coding in additive white Gaussian noise (AWGN) channels as well as fading channels. Our analysis includes downlink synchronous system as well as asynchronous system such as uplink mobile-to-base station communication. 展开更多
关键词 SPREAD SPECTRUM self-Encoded Multiple Access MULTIUSER Convolutional CODING MULTIUSER Detection
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Correlation Analysis between Self-Disclosure and Social Support in Patients with Breast Cancer
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作者 Yun Ding Liping Zhang +1 位作者 Huiying Qin Lijuan Zhang 《Advances in Breast Cancer Research》 CAS 2024年第4期59-68,共10页
Objective: Describe the status quo of self-disclosure and social support in breast cancer patients and analyze the correlation between them. Methods: General data questionnaire, distress disclosure Index scale and Chi... Objective: Describe the status quo of self-disclosure and social support in breast cancer patients and analyze the correlation between them. Methods: General data questionnaire, distress disclosure Index scale and Chinese version of medical social support scale were used to investigate the correlation between self-disclosure and social support in breast cancer patients by Pearson correlation analysis. Results: 1) The total self-disclosure score was (38.75 ± 9.18);the total score of social support was (70.57 ± 14.04) scores, including emotional information support dimension (28.39 ± 6.06) scores, practical support dimension (15.62 ± 3.31) scores, elastic support dimension (14.85 ± 3.23) scores, and emotional support dimension (11.70 ± 2.56) scores. 2) Self-disclosure was positively correlated with social support (r = 0.433, p Conclusion: Breast cancer patients had a moderate level of self-disclosure, and the higher the level of self-disclosure, the better the social support. It is suggested that improving the self-disclosure level of breast cancer patients can help them obtain more social support. 展开更多
关键词 Breast Cancer self-DISCLOSURE Social Support
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Evidence for self-organized criticality in unscheduled downtime data of equipment
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作者 Bo Li Feng Yang Daohan Zhou 《Journal of Systems Engineering and Electronics》 SCIE EI CSCD 2014年第6期1020-1026,共7页
How to reduce downtime and improve availability of the complex equipment is very important. Although the unscheduled downtime(USDT) issues of the equipment are very complex, the self-organized criticality(SOC) is ... How to reduce downtime and improve availability of the complex equipment is very important. Although the unscheduled downtime(USDT) issues of the equipment are very complex, the self-organized criticality(SOC) is the right theory to study complex systems evolution and opens up a new window to the investigation of disasters, such as the sudden failure of the equipment. Firstly,SOC theory and its validation method are introduced. Then an SOC validation method for USDT of the equipment is proposed based on the above theory. Case study is done on bottleneck equipment in a factory and corresponding data pre-process work is done. The rescaled-range(R/S) analysis method is used to calculate the Hurst exponent of USDT time-series data in order to determine the long-range correlation of USDT data on time scale;at the same time the spatial power-law characteristic of USDT time series data is studied. The result shows that the characteristics of SOC are revealed in USDT data of the equipment according to the criterion of SOC. In addition, based on the characteristics of SOC,the overall framework of the prediction method for major sudden failure of the equipment is proposed based on SOC. 展开更多
关键词 unscheduled downtime(USDT) self-organized criti-cality(SOC) rescaled-range analysis(R/S) Hurst exponent
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