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基于MacBERT和R-Drop的地质命名实体识别 被引量:1
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作者 刘昕 徐洪珍 +1 位作者 刘爱华 邓德军 《郑州大学学报(工学版)》 CAS 北大核心 2024年第3期89-95,共7页
地质命名实体识别中常用的基于BERT预训练模型的深度学习方法是基于字的方法,没有利用词信息,且神经网络中的Dropout机制会导致训练阶段和推理阶段之间存在不一致性。针对该问题,提出了一种基于MacBERT和R-Drop的地质命名实体识别模型M... 地质命名实体识别中常用的基于BERT预训练模型的深度学习方法是基于字的方法,没有利用词信息,且神经网络中的Dropout机制会导致训练阶段和推理阶段之间存在不一致性。针对该问题,提出了一种基于MacBERT和R-Drop的地质命名实体识别模型MBCR。首先,通过MacBERT学习文本特征表示,充分利用字词信息;其次,运用BiGRU编码上下文特征,有效提取完整的语义信息;最后,采用CRF获取标签间的依赖关系,生成最优标签序列。此外,在训练过程中引入R-Drop,进一步提升模型的泛化能力。结果表明:与BiLSTM-CRF、BERTBiLSTM-CRF等模型相比,所提MBCR模型在NERdata数据集上的F1值提高了2.08百分点~4.62百分点,在Boson数据集上的F1值提高了1.26百分点~17.54百分点。 展开更多
关键词 命名实体识别 地质 MacBERT BiGRU R-drop
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基于drop-off ddPCR方法检测急性髓系白血病C-KIT基因N822位点突变及其临床应用
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作者 李婷 金晔 +7 位作者 袁倩 姚冬明 向鹤麟 肖高飞 于迪 冷加燕 林江 钱军 《江苏大学学报(医学版)》 CAS 2024年第2期151-155,160,共6页
目的:建立急性髓系白血病(acute myeloid leukemia, AML)患者C-KIT基因N822位点突变的drop-off微滴式数字PCR(droplet digital PCR,ddPCR)定量检测方法,并评价其临床应用价值。方法:针对C-KIT基因第17外显子设计一对引物及探针,优化drop... 目的:建立急性髓系白血病(acute myeloid leukemia, AML)患者C-KIT基因N822位点突变的drop-off微滴式数字PCR(droplet digital PCR,ddPCR)定量检测方法,并评价其临床应用价值。方法:针对C-KIT基因第17外显子设计一对引物及探针,优化drop-off ddPCR反应条件及体系,评价该方法的特异性、灵敏度、重复性,使用所建立的方法对140例已行Sanger测序的AML初诊患者骨髓标本进行检测,并用二代测序(next generation sequencing, NGS)验证结果;用drop-off ddPCR对3例阳性患者化疗后C-KIT突变频率进行动态监测。结果:drop-off ddPCR检测C-KIT基因N822位点突变的最适退火温度为54℃,空白检测限为1.62拷贝数/μL,最低检测下限为10.12拷贝数/μL,线性良好。140例AML初诊患者样本中Sanger测序检出2例阳性(1.4%),而ddPCR共检出突变7例(5.0%),突变频率为0.29%~7.41%;进一步应用常规NGS方法对ddPCR阳性样本进行验证,共检出阳性3例(2.1%),等位基因频率为1.26%~8.00%。动态监测3例阳性患者C-KIT突变频率,结果显示治疗达完全缓解时C-KIT突变频率明显下降甚至降低至0。结论:本研究建立了检测C-KIT基因N822位点突变的drop-off ddPCR技术,具有良好的方法学检测性能,其灵敏度高于Sanger测序和NGS,有望用于阳性患者缓解后的可检测残留疾病监测及治疗指导。 展开更多
关键词 drop-off微滴式数字PCR C-KIT基因 基因突变 微小残留病 急性髓系白血病 预后
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A data-driven model of drop size prediction based on artificial neural networks using small-scale data sets 被引量:1
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作者 Bo Wang Han Zhou +3 位作者 Shan Jing Qiang Zheng Wenjie Lan Shaowei Li 《Chinese Journal of Chemical Engineering》 SCIE EI CAS CSCD 2024年第2期71-83,共13页
An artificial neural network(ANN)method is introduced to predict drop size in two kinds of pulsed columns with small-scale data sets.After training,the deviation between calculate and experimental results are 3.8%and ... An artificial neural network(ANN)method is introduced to predict drop size in two kinds of pulsed columns with small-scale data sets.After training,the deviation between calculate and experimental results are 3.8%and 9.3%,respectively.Through ANN model,the influence of interfacial tension and pulsation intensity on the droplet diameter has been developed.Droplet size gradually increases with the increase of interfacial tension,and decreases with the increase of pulse intensity.It can be seen that the accuracy of ANN model in predicting droplet size outside the training set range is reach the same level as the accuracy of correlation obtained based on experiments within this range.For two kinds of columns,the drop size prediction deviations of ANN model are 9.6%and 18.5%and the deviations in correlations are 11%and 15%. 展开更多
关键词 Artificial neural network drop size Solvent extraction Pulsed column Two-phase flow HYDRODYNAMICS
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Buckling Properties of Water-Drop-Shaped Pressure Hulls with Various Shape Indices Under Hydrostatic External Pressure
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作者 DING Xiao-de ZHANG Jian +2 位作者 WANG Fang JIAO Hui-feng WANG Ming-lu 《China Ocean Engineering》 SCIE EI CSCD 2024年第1期1-17,共17页
The water-drop-shaped pressure hull has a good streamline,which has good application prospect in the underwater observatory.Therefore,this study conducted analytical,experimental and numerical investigation of the buc... The water-drop-shaped pressure hull has a good streamline,which has good application prospect in the underwater observatory.Therefore,this study conducted analytical,experimental and numerical investigation of the buckling properties of water-drop-shaped pressure hulls under hydrostatic pressure.A water-drop experiment was conducted to design water-drop-shaped pressure hulls with various shape indices.The critical loads for the water-drop-shaped pressure hulls were resolved by using Mushtari’s formula.Several numerical simulations including linear buckling analysis and nonlinear buckling analysis including eigenmode imperfections were performed.The results indicated that the critical loads resolved by Mushtari's formula were in good agreement with the linear buckling loads from the numerical simulations.This formula can be extended to estimate the buckling capacity of water-drop-shaped pressure hulls.In addition,three groups of pressure hulls were fabricated by using stereolithography,a rapid prototyping technique.Subsequently,three groups of the pressure hulls were subjected to ultrasonic measurements,optical scanning,hydrostatic testing and numerical analysis.The experimental results were consistent with the numerical results.The results indicate that the sharp end of the water-drop-shaped pressure hulls exhibited instability compared with the blunt end.This paper provides a new solution to the limitations of experimental studies on the water-drop-shaped pressure hulls as well as a new configuration and evaluation method for underwater observatories. 展开更多
关键词 BUCKLING pressure hull water drop underwater observatory
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Evaluation of frictional pressure drop correlations for air-water and air-oil two-phase flow in pipeline-riser system
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作者 Nai-Liang Li Bin Chen 《Petroleum Science》 SCIE EI CAS CSCD 2024年第2期1305-1319,共15页
Accurate prediction of the frictional pressure drop is important for the design and operation of subsea oil and gas transporting system considering the length of the pipeline. The applicability of the correlations to ... Accurate prediction of the frictional pressure drop is important for the design and operation of subsea oil and gas transporting system considering the length of the pipeline. The applicability of the correlations to pipeline-riser flow needs evaluation since the flow condition in pipeline-riser is quite different from the original data where they were derived from. In the present study, a comprehensive evaluation of 24prevailing correlation in predicting frictional pressure drop is carried out based on experimentally measured data of air-water and air-oil two-phase flows in pipeline-riser. Experiments are performed in a system having different configuration of pipeline-riser with the inclination of the downcomer varied from-2°to-5°to investigated the effect of the elbow on the frictional pressure drop in the riser. The inlet gas velocity ranges from 0.03 to 6.2 m/s, and liquid velocity varies from 0.02 to 1.3 m/s. A total of885 experimental data points including 782 on air-water flows and 103 on air-oil flows are obtained and used to access the prediction ability of the correlations. Comparison of the predicted results with the measured data indicate that a majority of the investigated correlations under-predict the pressure drop on severe slugging. The result of this study highlights the requirement of new method considering the effect of pipe layout on the frictional pressure drop. 展开更多
关键词 Frictional pressure drop Pipeline-riser Gas-liquid two-phase flow Severe slugging CORRELATION
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A combined computational/experimental study of anode-concerned voltage drop in aqueous primary Mg-air batteries
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作者 Wen Xu Min Deng +5 位作者 Darya Snihirova Linqian Wang Yulong Wu Sviatlana V.Lamaka Mikhail L.Zheludkevich Daniel Hoche 《Journal of Magnesium and Alloys》 SCIE EI CAS CSCD 2024年第5期1854-1866,共13页
The voltage drop appearing at Mg anode-electrolyte interface is a critical issue for the battery power and energy density of aqueous primary Mg-air batteries.The respective voltage loss is typically assigned to the de... The voltage drop appearing at Mg anode-electrolyte interface is a critical issue for the battery power and energy density of aqueous primary Mg-air batteries.The respective voltage loss is typically assigned to the deposits layer forming on the anode surface during discharge.In this work,we experimentally and computationally investigate the critical factors affecting the voltage drop at Mg anode towards a deeper understanding of the contribution of deposit and its growth.A two-dimensional(2D)mathematical model is proposed to compute the voltage drop of Mg-0.15Ca wt.%alloy(Mg-0.15Ca)by means of a semi-empirical formulas and experiments-based modification model,considering the effect of discharge current density,the negative difference effect(NDE)and surface deposits layer itself.This model is utilized to simulate the discharge potential of the anode at predefined experimental current densities.The computed voltage drop(half-cell voltage)is in good agreement with the experimental value.The applicability of the mathematical model is successfully validated on the second material(namely high-purity Mg). 展开更多
关键词 Aqueous Mg-air battery Voltage drop NDE Charge transfer Deposits-related resistances
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Ladder Time Stepwise Inertia Coordinated Control Method of Multiple Wind Farms to Suppress System Frequency Secondary Drop
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作者 He Li Xianchao Liu +1 位作者 Jidong Li Yuchen Qiu 《Energy Engineering》 EI 2024年第8期2293-2311,共19页
Currently,both regulated and deregulated power trading exist in China’s power system,which has caused imbalanced funds in the electricity market.In this paper,a simulation analysis of the electricity market with wind... Currently,both regulated and deregulated power trading exist in China’s power system,which has caused imbalanced funds in the electricity market.In this paper,a simulation analysis of the electricity market with wind energy resources is conducted,and the calculation methods of unbalanced funds are investigated systematically.In detail,the calculation formulas of unbalanced funds are illustrated based on their definition,and a two-track electricity market clearing model is established.Firstly,the concept of the dual-track system is explained,and the specific calculation formulas of various types of unbalanced funds are provided.Next,considering the renewable energy consumption,the market clearing model based on DC power flow is constructed and solved;by combining fitting methods of mid-and long-term curves,the unbalanced funds are calculated based on clearing results and formulas. 展开更多
关键词 Wind power stepwise inertial frequency control secondary drop
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Efficacy of recombinant human epidermal growth factor plus sodium hyaluronate eye drops in diabetic dry eye post-cataract surgery
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作者 Jun-Ling Li Jin Zhao +2 位作者 Zhen-Feng Guo Chang Xiao Xuan Liu 《World Journal of Diabetes》 SCIE 2024年第6期1234-1241,共8页
BACKGROUND Dry eye syndrome(DES)after diabetic cataract surgery can seriously affect the patient’s quality of life.Therefore,effective alleviation of symptoms in patients with this disease has important clinical sign... BACKGROUND Dry eye syndrome(DES)after diabetic cataract surgery can seriously affect the patient’s quality of life.Therefore,effective alleviation of symptoms in patients with this disease has important clinical significance.AIM To explore the clinical effect of recombinant human epidermal growth factor(rhEGF)plus sodium hyaluronate(SH)eye drops on DES after cataract surgery in patients with diabetes.METHODS We retrospectively evaluated 82 patients with diabetes who experienced DES after cataract surgery at Tianjin Beichen Hospital,Affiliated Hospital of Nankai University between April 2021 and April 2023.They were classified into an observation group(42 cases,rhEGF+SH eye drops)and a control group(40 cases,SH eye drops alone),depending on the different treatment schemes.The therapeutic efficacy,dry eye symptom score,tear film breakup time(TFBUT),basic tear secretion score[assessed using Schirmer I test(SIt)],corneal fluorescein staining(FL)score,tear inflammatory markers,adverse reactions during treat-ment,and treatment satisfaction were compared between the two groups.RESULTS Therapeutic efficacy was higher in the observation group compared with the control group.Both groups showed improved TFBUT and dry eye,as well as improved SIt and FL scores after treatment,with a more pronounced improvement in the observation group.Although no marked differences in adverse reactions were observed between the two groups,treatment satisfaction was higher in the observation group.CONCLUSION rhEGF+SH eye drops rendered clinical benefits to patients by effectively ameliorating dry eye and visual impairment with favorable efficacy,fewer adverse reactions,and high safety levels.Thus,this treatment should be promoted in clinical practice. 展开更多
关键词 Recombinant human epidermal growth factor Sodium hyaluronate eye drops Diabetic patients Dry eye syndrome after cataract surgery Therapeutic efficacy
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Flow Rate Measurement of Gravity Infusion Set and Functional Evaluation of Drop Counter: A Pilot Study
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作者 Rina Sakai Shuichi Tanaka +3 位作者 Kaya Murakami Tomomi Mizuhashi Kazuhiro Yoshida Masanobu Ujihira 《Journal of Biomedical Science and Engineering》 2024年第7期129-135,共7页
Developing a novel drop counter by introducing the Internet of Things concept has been vigorously conducted in recent years. Understanding the newly introduced drop counter’s flow rate control accuracy and flow rate ... Developing a novel drop counter by introducing the Internet of Things concept has been vigorously conducted in recent years. Understanding the newly introduced drop counter’s flow rate control accuracy and flow rate count feature is essential for improving safety in infusion management. This study aimed to verify if the new drop counters could secure accurate flow rate and drip count by conducting actual flow rate measurements using gravimetry and functional evaluation. A drop counter was attached to each drip chamber of the infusion set, and an IV drip was conducted at the 100 ml/h flow rate. The weight of discharged physiological saline was measured to plot trumpet curves. Next, three different types of drop counters were evaluated to determine if they maintained drip count accuracy according to the changes in their position angles. The flow rate errors in all conditions indicated trumpet-like curves, exhibiting an overall error range within ±10% in all observation windows. Although every drop counter successfully detected and measured dripping, it was challenging in some counters to detect dripping when the drip chamber was tilted. In comparing adult and pediatric IV sets, the adult IV set was found to be less likely to detect dripping in the angled position. No significant differences in results were confirmed between high and low flow rates, suggesting that the drop count function would not be affected by the flow rate in the ranges of typical infusion practices. Doppler sensors have a wide range of measurements and high sensitivity;the dripping was detected successfully even when the drip chamber was tilted, probably due to the advantages of these sensors. In contrast, miscounts occurred in those equipped with infrared sensors, which could not detect light intensity changes in tilted positions. Understanding the tendencies in flow rate errors in infusion can be valuable information for infusion management. 展开更多
关键词 Gravity Infusion Set drop Counter IV Fluids Flow Rate Trumpet Curves
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Prevalence and Factors Associated with Dry Eyes Syndrome in Glaucomatous Patients on Anti-Glaucoma Eye Drops Followed up at the Garoua Regional Hospital-Northern Cameroon
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作者 Josiane Mare Njoya Dodo Balkissou +3 位作者 Bimingo Noelle Bra’ Eyatcha Viola Dohvoma Yannick Bilong Godefroy Koki 《Open Journal of Ophthalmology》 2024年第3期350-360,共11页
Background: Dry eye and glaucoma are two common pathologies in the elderly, and are very often associated. This association suggests a link between them and between their treatments. Our purpose for this study is to d... Background: Dry eye and glaucoma are two common pathologies in the elderly, and are very often associated. This association suggests a link between them and between their treatments. Our purpose for this study is to determine the prevalence of dry eye in our glaucoma patients treated with eye drops and deduce the factors associated with it. Patients and Methods: We conducted a cross-sectional, analytical study from October 2022 to September 2023 in the ophthalmology department of Garoua Regional Hospital in glaucoma patients aged over 15 years able to answer the Ocular Surface Disease Index (OSDI) questionnaires and treated with antiglaucoma eye drops for more than 3 months. These patients underwent a complete ophthalmological examination and a tear film break-up time test. Results: A total of 73 patients (146 eyes) were examined. The average age of the patients was 47.2 ± 16.5 years, with a male predominance of 54.8%. The prevalence of dry eye syndrome in our patients according to the OSDI score was 56.2% (95% CI) (44.8;67.6). The prevalence of dry eye syndrome on clinical examination of the BUT in the right eye was 83.7% (95% CI) (75.1;92.1) and 79.4% (70.2;88.7) in the left eye. The duration of antiglaucoma treatment was the factor associated with dry eye syndrome (p < 0.05) in glaucoma patients in our setting. Conclusion: Dry Eye Syndrome is common in glaucoma patients on drops in our setting. Treatment duration of more than 1 year seems to be associated with dry eyes. 展开更多
关键词 Dry Eyes GLAUCOMA Conservative Eye drops Médications Garoua-Cameroon
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The Effect of Ginkgo Biloba Leaf Dropping Pill Combined with Butylphthalide Capsule on Cognitive Dysfunction in Patients after Acute Ischemic Stroke and Its Impact on Serum Cytokines
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作者 Yaojie Cai Yuping He +1 位作者 Gang Yang Yan Chen 《Journal of Biosciences and Medicines》 2024年第7期252-262,共11页
Objective: To investigate the therapeutic effect of Ginkgo biloba extract dropping pills combined with butylphthalide capsules on cognitive dysfunction in patients after acute ischemic stroke (AIS) and its impact on s... Objective: To investigate the therapeutic effect of Ginkgo biloba extract dropping pills combined with butylphthalide capsules on cognitive dysfunction in patients after acute ischemic stroke (AIS) and its impact on serum cytokines CRP, IL-6, and Hcy. Methods: This study selected 76 patients with cognitive dysfunction after ischemic stroke who were hospitalized at Zhuji People’s Hospital from January 2023 to January 2024. The patients were divided into two groups. The control group was treated with butylphthalide capsules, while the combination group received Ginkgo biloba extract dropping pills in addition to the treatment given to the control group. The neurological function, cognitive function, activities of daily living, and levels of serum cytokines CRP, IL-6, and Hcy were compared between the two groups after 1 month and 3 months of treatment. Results: The NIHSS scores, MMSE scores, ADL scores, and levels of CRP, IL-6, and Hcy in both groups showed statistically significant differences compared to before treatment (P Conclusion: The combination of Ginkgo biloba extract dropping pills and butylphthalide capsules has a better therapeutic effect on cognitive dysfunction in patients after ischemic stroke. It can improve the neurological function and cognitive function of patients, enhance their ability to perform daily activities, and reduce inflammatory responses. 展开更多
关键词 Acute Ischemic Stroke Ginkgo Biloba Leaf drop Pills Butylphthalein Cognitive Impairment
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Temperature Drop of Molten Metals in Open Channels
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作者 Miguel A. Barron-Meza Joan Reyes-Miranda 《World Journal of Engineering and Technology》 2024年第3期493-500,共8页
The temperature drop of molten metal flowing in open channels is numerically determined. Rectangular, trapezoidal and triangular geometries are considered. The overall heat transfer coefficients for the bottom, side w... The temperature drop of molten metal flowing in open channels is numerically determined. Rectangular, trapezoidal and triangular geometries are considered. The overall heat transfer coefficients for the bottom, side walls and free surface of the channel have been taken from the literature. For each geometry, the volumetric flow rate, mean residence time and temperature drop as a function of the channel inclination angle were determined. The rectangular and trapezoidal geometries present the smallest temperature drops, while the triangular geometry presents the greatest temperature drop. The factors that most affect this drop are the value of the free surface area of the channel, and the average residence time of the molten metal in the channel. 展开更多
关键词 Free Surface Heat Transfer Molten Metal Open Channel Geometry Residence Time Temperature drop
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Improvement of Temperature Drop Model Parameters for 4200mm/3500mm Rolling of Baosteel Medium and Thick Plate
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作者 Kong Peng 《Frontiers of Metallurgical Industry》 2024年第1期27-30,共4页
Based on the temperature situation during the rolling process of 4200 mm/3500 mm medium and thick plates at Baosteel,this article analyzes the influencing factors of temperature changes during the rolling process from... Based on the temperature situation during the rolling process of 4200 mm/3500 mm medium and thick plates at Baosteel,this article analyzes the influencing factors of temperature changes during the rolling process from the perspective of heat transfer theory and the temperature change law during the rolling process.The temperature loss during the four rolling processes is tracked on site,and the temperature drop model parameters during the rolling process of 4200mm/3500mm medium and thick plates at Baosteel are quantitatively provided.It is applied to actual rolling production and has achieved good results. 展开更多
关键词 medium thickness plate rolling process temperature drop
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Basic Research on the Burden of Dropping off and Picking up Children: Differences by Employment Type and Gender in the Tokyo Metropolitan Area
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作者 Jun Morio Koshi Isono +1 位作者 Masahiko Kikuchi Tetsuo Morita 《Journal of Transportation Technologies》 2024年第3期445-461,共17页
There is a need to reduce the burden of child drop-off and pick-up for child-rearing generations, but most studies on the actual situation in Japan are based on survey results. In this study, we analyzed differences i... There is a need to reduce the burden of child drop-off and pick-up for child-rearing generations, but most studies on the actual situation in Japan are based on survey results. In this study, we analyzed differences in child drop-off and pick-up by employment type and gender, utilizing the “Metropolitan Area Person Trip Survey,” which is a statistical data set. The study targeted households in which both spouses were between 30 and 49 years old, had children under the age of 6, and included the following three groups. 1) Dual-income Group 1 (both spouses employed/on contract/temporary);2) Dual-income Group 2 (husband employed/on contract/temporary, wife part-time);3) Full-time housewife group (husband employed, wife unemployed). The analysis revealed that a) wives are almost always responsible for dropping off and picking up their children;b) husbands drop off and pick up their children less frequently in dual-income households;and c) households with children raising within 10 to 30 km of Tokyo Station have longer commuting times and need to reduce the burden of dropping off and picking up their children. 展开更多
关键词 drop-Off and Pick-Up Employment Type GENDER Dual-Income Households Tokyo Metropolitan Area
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Clinical Observation of Recombinant Bovine Basic Fibroblast Growth Factor Eye Gel Combined with Tobramycin Dexamethasone Eye Drops in the Treatment of Dry Eye Syndrome in Patients after Cataract Surgery
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作者 Zhishun Mao Xiaoxue Mei 《Journal of Clinical and Nursing Research》 2024年第8期296-301,共6页
Objective:To evaluate the therapeutic effect of recombinant bovine basic fibroblast growth factor(rbFGF)eye gel combined with tobramycin-dexamethasone(TOB-Dex)eye drops on dry eye syndrome(DES)after cataract surgery.M... Objective:To evaluate the therapeutic effect of recombinant bovine basic fibroblast growth factor(rbFGF)eye gel combined with tobramycin-dexamethasone(TOB-Dex)eye drops on dry eye syndrome(DES)after cataract surgery.Methods:86 patients with DES after cataract surgery,admitted from November 2021 to November 2023,were randomly divided into groups.The observation group included 43 patients treated with rbFGF eye gel combined with TOB-Dex eye drops.The reference group included 43 patients treated with TOB-Dex eye drops alone.Multiple indicators,including total effective rate and clinical symptom scores,were compared between the two groups.Results:The total effective rate in the observation group was higher than in the reference group(P<0.05).Before treatment,there were no differences in clinical symptom scores,serum factors,or disease severity scores between the two groups(P>0.05).Three weeks after treatment,the observation group had lower clinical symptom scores,serum factors,and disease severity scores compared to the reference group(P<0.05).The adverse reaction rate in the observation group was lower than in the reference group(P<0.05).Conclusion:rbFGF eye gel combined with TOB-Dex eye drops can improve the clinical efficacy for patients with DES after cataract surgery,alleviate disease symptoms,reduce inflammatory responses,and have fewer adverse reactions. 展开更多
关键词 Recombinant bovine basic fibroblast growth factor eye gel Tobramycin-dexamethasone eye drops Cataract surgery Dry eye syndrome
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电磁脉冲攻击下片上配电网络IR Drop分析方法
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作者 刘强 张培然 《计算机辅助设计与图形学学报》 EI CSCD 北大核心 2024年第4期582-590,共9页
电磁脉冲攻击对集成电路的安全具有很强的威胁性.为了有效地抵御电磁脉冲攻击,针对片上配电网络易受电磁脉冲影响的问题,提出了一种电磁脉冲攻击下片上配电网络IRdrop分布的分析方法.首先,在集成电路布局规划阶段,基于有限元仿真构建片... 电磁脉冲攻击对集成电路的安全具有很强的威胁性.为了有效地抵御电磁脉冲攻击,针对片上配电网络易受电磁脉冲影响的问题,提出了一种电磁脉冲攻击下片上配电网络IRdrop分布的分析方法.首先,在集成电路布局规划阶段,基于有限元仿真构建片上配电网络模型和电磁脉冲攻击模型,仿真获得电磁脉冲下配电网络上感应电流密度的分布并计算感应电流,然后将感应电流加载到配电网络模型上,使用IR分析工具分析IRdrop分布.基于TSMC180 nm工艺版图的IR drop分析结果显示,电磁脉冲攻击能够在电源和地网络中引入2.3 V以上的IR drop.与现有基于电流分布理论值的分析方法相比,该分析方法能够更准确地获取电磁脉冲下配电网络中的IR drop分布.该分析方法可用于指导改进配电网络的设计,提升抗电磁脉冲攻击能力.实验结果显示,增加一组供电端口后,电源和地网络中的最大IR drop分别降低了28%和24%. 展开更多
关键词 集成电路 片上配电网络 电磁脉冲攻击 电压降
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局部凸Hausdorff空间中的Drop定理和Drop性质 被引量:1
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作者 贺飞 刘德 +1 位作者 罗成 许成锋 《内蒙古大学学报(自然科学版)》 CAS CSCD 北大核心 2006年第3期251-257,共7页
证明了局部凸H ausdorff空间中的一个D rop定理,提出了局部凸H ausdorff空间中的-τdrop性质、拟-τdrop性质和局部D rop性质.并证明τ-序列紧凸集具有-τdrop性质,τ-可数紧凸集具有拟-τdrop性质以及局部序列紧凸集都具有局部D rop性质.
关键词 局部凸空间 drop定理 τ-drop性质 拟τ-drop性质 局部drop性质
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A-DROP评分对老年社区获得性肺炎临床结局的预测价值 被引量:5
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作者 陈冬梅 达·霹莉情 +2 位作者 杨倩 韩美荣 陈燕 《西部医学》 2023年第1期125-129,共5页
目的探讨A-DROP评分对老年社区获得性肺炎临床结局的预测价值。方法回顾性分析2019年1月~2020年12月本院呼吸与危重症医学科收治的老年社区获得性肺炎患者(CAP)临床资料,入院后24 h内完成血常规、生化等检测,并完成A-DROP、PSI、CURB-6... 目的探讨A-DROP评分对老年社区获得性肺炎临床结局的预测价值。方法回顾性分析2019年1月~2020年12月本院呼吸与危重症医学科收治的老年社区获得性肺炎患者(CAP)临床资料,入院后24 h内完成血常规、生化等检测,并完成A-DROP、PSI、CURB-65评分,根据28 d结局分为死亡及存活组,通过比较受试者工作特征曲线(ROC)分析A-DROP、PSI、CURB-65对患者28 d死亡率的预测效能。结果共纳入137例老年CAP患者,其中死亡组23例,存活组114例,A-DROP、PSI、CURB-65评分在死亡组中更高(P<0.0001);A-DROP、CURB-65、PSI危险分层预测老年CAP患者28 d死亡率的AUC值分别为0.759、0.732、0.755,A-DROP的截断值为极严重组,其敏感性为82.61%,特异性为65.79%;依据A-DROP进行危险分层,极严重组患者中位生存时间为22.638天(95%CI:20.096~25.180),极严重组患者死亡风险是中度组患者8.56倍(95%CI 3.3~22.21),是严重组患者的4.28倍(95%CI:1.32~13.9)。结论A-DROP评分系统对老年CAP患者死亡率具有一定预测价值,与PSI、CURB-65的预测效能相当。 展开更多
关键词 社区获得性肺炎 PSI CURB-65 A-drop 预后
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Drop-off微滴式数字PCR检测急性髓系白血病NRAS基因突变及其临床应用 被引量:1
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作者 向鹤麟 金晔 +6 位作者 袁倩 姚冬明 李婷 于迪 冷加燕 林江 钱军 《江苏大学学报(医学版)》 CAS 2023年第1期49-53,共5页
目的:建立检测急性髓系白血病(acute myeloid leukemia,AML)神经母细胞瘤RAS病毒癌基因同源物(NRAS)基因突变的drop-off微滴式数字PCR(droplet digital PCR,ddPCR)方法,并评价该方法的临床应用价值。方法:针对NRAS G12和G13突变位点设... 目的:建立检测急性髓系白血病(acute myeloid leukemia,AML)神经母细胞瘤RAS病毒癌基因同源物(NRAS)基因突变的drop-off微滴式数字PCR(droplet digital PCR,ddPCR)方法,并评价该方法的临床应用价值。方法:针对NRAS G12和G13突变位点设计特异性drop-off ddPCR引物和探针,建立最佳反应体系,并对该方法进行性能验证。应用该方法对140例临床样本进行初筛,其检测结果与Sanger测序进行比较,并用二代测序(next generation sequencing,NGS)进行验证。结果:建立drop-off ddPCR检测NRAS基因G12/G13突变的方法,灵敏度达0.158%,重复性、线性良好,其空白限为5.40拷贝数/μL,最低检测下限为15.84拷贝数/μL。在140例初诊AML患者中,drop-off ddPCR检出NRAS突变28例(20%),其突变负荷为0.26%~52.85%(中位2.14%);而Sanger测序仅检出7例(5%)阳性,为进一步验证,将21例Sanger测序结果阴性而drop-off ddPCR检测阳性的样本进行NRAS基因NGS,检出14例阳性,而另外7例NGS阴性的样本,其drop-off ddPCR检测突变频率为0.53%~1.50%(中位1.10%)。结论:建立了drop-off ddPCR技术检测AML患者中NRAS基因突变的方法,该方法灵敏度高,可用于对NRAS基因G12/G13突变进行定量检测,有望可用于AML患者预后判断和疾病监测。 展开更多
关键词 drop-off微滴式数字PCR NRAS基因 急性髓系白血病 基因突变 微小残留病灶 预后
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基于GRU-GCN-RDrop模型的交通速度预测 被引量:1
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作者 赵嘉雨 段亚茹 何立明 《计算机技术与发展》 2023年第4期120-125,139,共7页
准确并实时地预测交通速度是实现智能交通管控和建设智慧交通系统必不可少的一环,然而现有的预测方法无法准确地挖掘其潜在的时空相关性。为了进一步挖掘数据的时空特性以及提高预测精度,设计了基于门控循环神经网络(GRU),图卷积网络(G... 准确并实时地预测交通速度是实现智能交通管控和建设智慧交通系统必不可少的一环,然而现有的预测方法无法准确地挖掘其潜在的时空相关性。为了进一步挖掘数据的时空特性以及提高预测精度,设计了基于门控循环神经网络(GRU),图卷积网络(GCN)和正则化Dropout(R-Drop)结合的GRU-GCN-RDrop组合模型。GCN用于学习复杂的拓扑结构来捕获空间依赖性,GRU用于学习交通数据的动态变化来捕获时间依赖性。GCN和GRU相结合后使用R-Drop方法提高模型泛化能力。以SZ-taxi数据集为例进行预测分析,GRU-GCN-RDrop模型预测了未来在15分钟、30分钟、45分钟和60分钟的交通速度,并得出对应的均方根误差、平均绝对误差、精度、判定系数和解释方差。对比GCN、GRU单个模型,GRU-GCN-RDrop模型有效解决了误差的迅速累积问题。对比大多数现有基准模型,GRU-GCN-RDrop模型对于交通速度序列的特征提取及解释能力较为优秀。对比T-GCN模型和ST-AGTCN模型,GRU-GCN-RDrop模型泛化能力更强。由此说明了GRU-GCN-RDrop模型预测的交通速度时间序列具有较高的精度和稳定性。 展开更多
关键词 智慧交通系统 交通速度预测 图卷积网络 门控循环单元 正则化dropout
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