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The path to carbon neutral shipping:A comparative analysis of low carbon technologies
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作者 Zhengang Zhou Zhicheng Wu +8 位作者 Chang Liu Lingyu Shao You Zhang Weijie Liu Haitao Shen Dongwei Yao Haidong Fan Chenghang Zheng Xiang Gao 《Journal of Environmental Sciences》 2026年第1期606-616,共11页
Ship operations are crucial to global trade,and their decarbonization is essential to mitigate climate change.This study evaluates the economic viability of existing and emerging decarbonization technologies in mariti... Ship operations are crucial to global trade,and their decarbonization is essential to mitigate climate change.This study evaluates the economic viability of existing and emerging decarbonization technologies in maritime shipping using the levelized cost of energy methodology.It includes a detailed comparative analysis based on essential criteria and sensitivity assessments to highlight the economic impacts of technological advancements.Key factors influencing total costs include fuel costs,carbon pricing,and energy demands for carbon capture.The findings reveal that methanol is more cost-effective than heavy fuel oil(HFO)when priced below 3000 CNY/t,assuming HFO costs 4400 CNY/t.Additionally,methanol with post-combustion carbon capture is less expensive than pre-combustion carbon capture.When carbon prices rise above 480 CNY/t,carbon capture technologies prove more economical than purchasing carbon emission allowances for HFO and liquefied natural gas.Enhanc-ing the use of exhaust gas waste heat is recommended for cost savings.Post-combustion carbon capture also shows greater efficiency,requiring about 1.1 GJ/t less energy than pre-combustion methods,leading to lower overall costs.Future research should focus on market mechanisms to stabilize fuel prices and develop less energy-intensive carbon capture technologies.This study offers critical insights into effective decarbonization strategies for advancing global maritime trade in the present and future. 展开更多
关键词 SHIP low carbon ASSESSMENT Alternative fuel Carbon capture
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Data Processing Solutions on Low Signal-to-noise Data in Loess Plateau Area:A Case Study in Ordos Basin,China
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作者 GAO Rongtao CHENG Yun +1 位作者 TANG Ziqi LIU Zhao 《CT理论与应用研究(中英文)》 2026年第1期154-162,共9页
While the Ordos Basin is recognized for its substantial hydrocarbon exploration prospects,its rugged loess tableland terrain has rendered seismic exploration exceptionally challenging[1-3].Persistent obstacles such as... While the Ordos Basin is recognized for its substantial hydrocarbon exploration prospects,its rugged loess tableland terrain has rendered seismic exploration exceptionally challenging[1-3].Persistent obstacles such as complex 3D survey planning,low signal-tonoise ratio raw data,inadequate near-surface velocity modeling,and imaging inaccuracy have long hindered the advancement of seismic exploration across this region.Through a problem-solving approach rooted in geological target analysis,this research systematically investigates the behavioral patterns of nodal seismometer-based high-density seismic acquisition in loess plateau.Tailored advancements in waveform enhancement and depth velocity modelling methodologies have been engineered.Field validations confirm that the optimized workflow demonstrates marked improvements in amplitude preservation and imaging resolution,offering novel insights for future reservoir characterization endeavors. 展开更多
关键词 loess plateau ACQUISITION low signal to noise ratio data processing depth modeling
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Clinical Investigation into the Functional Rehabilitation of Patients with Chronic Low Back Pain Utilizing Core Stability Training Combined with Conventional Rehabilitation
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作者 Fei LI Jinlun WU 《Medicinal Plant》 2026年第1期40-42,45,共4页
[Objectives]To investigate the clinical efficacy of core stability training combined with conventional rehabilitation in the functional recovery of patients suffering from chronic low back pain.[Methods]A randomized c... [Objectives]To investigate the clinical efficacy of core stability training combined with conventional rehabilitation in the functional recovery of patients suffering from chronic low back pain.[Methods]A randomized controlled trial design was employed in this study.Ninety patients with chronic low back pain were recruited and randomly assigned to either a control group(n=45),which received conventional rehabilitation,or an experimental group(n=45),which received conventional rehabilitation combined with core stability training.Both groups underwent treatment for 6 weeks.Assessments were conducted using the visual analogue scale(VAS),Oswestry disability index(ODI),and finger-to-floor test prior to treatment,6 weeks following treatment,and during the follow-up period,respectively.[Results]Prior to treatment,no statistically significant differences were observed between the two patient groups in terms of general information and various baseline measurements(P>0.05).Following 6 weeks of treatment and throughout the follow-up period,both groups demonstrated significant improvements in VAS scores,ODI scores,and lumbar anteflexion range of motion compared to baseline measurements(P<0.05).Notably,the magnitude of improvement in the experimental group exceeded that of the control group,with this inter-group difference reaching statistical significance(P<0.05).No serious adverse reactions were reported during the treatment process.[Conclusions]Core stability training combined with conventional rehabilitation can significantly enhance the alleviation of pain and functional impairments in patients suffering from chronic low back pain.This approach holds valuable implications for the optimization of rehabilitation treatment protocols. 展开更多
关键词 Chronic low back pain Core stability training Functional impairment PAIN
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Case studies of ion focusing in the downstream region of a modeled low Earth orbit spacecraft
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作者 Nizam Ahmad Hideyuki Usui +4 位作者 Yohei Miyake Slamet Supriadi Hanif Fakhrurroja Hilman Syaeful Alam Harry Bangkit 《Earth and Planetary Physics》 2026年第1期136-143,共8页
The effect of plasma and charged particle interaction with spacecraft in a low Earth orbit(LEO)environment leads to ion focusing and the formation of an ion void in the downstream region as a result of charging.Simula... The effect of plasma and charged particle interaction with spacecraft in a low Earth orbit(LEO)environment leads to ion focusing and the formation of an ion void in the downstream region as a result of charging.Simulations and investigations using a fixed potential imposed on the spacecraft showed the nonsignificance of geophysical parameter changes to ion focusing.Variation of the temperature ratio(T_(r))contributed only to local ion focusing and manifested as two-ion streamers dispersed at the upper and lower edges of the spacecraft-the outermost layers of the satellite structure at the top and bottom,respectively.A simulation involving changing the ambient plasma density(N_(p))also showed the formation of local ion focusing,in which ions were more concentrated as the density increased.Furthermore,auroral electron density(N_(ae))variation had no clear impact on ion focusing,as indicated by static two-ion structures in the wake field.However,variation of the object potential(ϕ)strongly affected ion focusing formation,leading to distortion of the initial ion void region behind the spacecraft.The formation of ion focusing in this study was subject to the electric field produced by the object potential and the ambipolar electric field resulting from plasma expansion in the downstream region. 展开更多
关键词 ion focusing spacecraft potential low Earth orbit environment
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含Low-E复合真空玻璃结构对建筑能耗的影响
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作者 程海强 王永帅 +3 位作者 佟恒冲 周飞翔 李志浩 毕一凡 《建筑节能(中英文)》 2026年第1期13-18,40,共7页
针对含Low-E膜层不同结构的复合真空玻璃,利用Window软件对玻璃中间部位进行热工模拟计算,然后采用Therm软件计算得到70系列断桥铝外窗整窗的热工参数。针对我国5个气候区,对小型酒店建筑采用DeST软件模拟量化不同气候区下复合真空玻璃... 针对含Low-E膜层不同结构的复合真空玻璃,利用Window软件对玻璃中间部位进行热工模拟计算,然后采用Therm软件计算得到70系列断桥铝外窗整窗的热工参数。针对我国5个气候区,对小型酒店建筑采用DeST软件模拟量化不同气候区下复合真空玻璃结构对建筑能耗的影响规律。模拟结果表明:复合真空玻璃结构对玻璃中部及整窗的传热系数和太阳得热系数均有较大影响,Low-E膜位于真空层内的室内侧或室外侧时,玻璃中部及整窗的传热系数相同且最小;随着Low-E膜辐射率的增加及光热比的降低,玻璃中部及整窗的太阳得热系数及传热系数均逐渐增加;当Low-E膜朝向室内时,太阳得热系数较其朝向室外有大幅降低;整体来看,复合真空玻璃的传热系数明显低于双中空玻璃,节能优势明显;较高的太阳得热系数有利于降低热负荷,但会增加冷负荷,为降低建筑总能耗,针对太阳得热系数应结合当地气候特点对复合真空玻璃结构进行具体设计。 展开更多
关键词 复合真空玻璃 low-E膜 热工模拟 建筑能耗
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高性能可钢化三银Low-E玻璃的膜系设计与制备工艺研究
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作者 田永刚 彭枢强 +4 位作者 续芯如 诸葛 勤美 耿立宏 彭响方 《玻璃》 2026年第1期50-58,共9页
三银Low-E玻璃因具有优异的光学选择性和节能潜力而成为研究热点,但其复杂的膜系结构往往导致热稳定性不足,难以承受后续的热处理加工,限制了其在安全玻璃领域的应用。为此,研究设计并制备了一种具有多层复合膜系的高性能可热处理加工三... 三银Low-E玻璃因具有优异的光学选择性和节能潜力而成为研究热点,但其复杂的膜系结构往往导致热稳定性不足,难以承受后续的热处理加工,限制了其在安全玻璃领域的应用。为此,研究设计并制备了一种具有多层复合膜系的高性能可热处理加工三银Low-E玻璃。通过引入氧化锌锡(ZnSnO)吸收层与多层复合保护结构,并优化真空磁控溅射工艺参数,系统研究了膜层结构对玻璃光学性能、颜色表现、热工性能及后续热处理加工适应性的影响。结果表明,所制备的玻璃样品在可见光透过率高于62%的同时,辐射率低至0.017,且颜色均匀性优异(ΔE_(ab)^(*)≤1.5)。经钢化处理后,其制成的中空玻璃冬季传热系数(K值)低至1.33 W/(m^(2)·K),遮阳系数(SC)仅为0.326,光热比(LSG)可达2.1以上,为三银Low-E玻璃在近零能耗建筑中的大规模工程化应用提供了可靠的技术路径。 展开更多
关键词 三银低辐射玻璃 真空磁控溅射 膜系设计
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Dipole-dipole interactions in electrolyte to facilitate Li-ion desolvation for low-temperature Li-ion batteries 被引量:1
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作者 Changlin Liu Zongjun Li +3 位作者 Lili Jiang Hao Zhu Fengchao Wang Lizhi Sheng 《Journal of Energy Chemistry》 2025年第5期678-686,共9页
Lithium-ion batteries are widely recognized as prime candidates for energy storage devices.Ethylene carbonate(EC)has become a critical component in conventional commercial electrolytes due to its exceptional film-form... Lithium-ion batteries are widely recognized as prime candidates for energy storage devices.Ethylene carbonate(EC)has become a critical component in conventional commercial electrolytes due to its exceptional film-forming properties and high dielectric constant.However,the elevated freezing point,high viscosity,and strong solvation energy of EC significantly hinder the transport rate of Li^(+)and the desolvation process at low temperatures.This leads to substantial capacity loss and even lithium plating on graphite anodes.Herein,we have developed an efficient electrolyte system specifically designed for lowtemperature conditions,which consists of 1.0 M lithium bis(fluorosulfonyl)imide(LiFSI)in isoxazole(IZ)with fluorobenzene(FB)as an uncoordinated solvent and fluoroethylene carbonate(FEC)as a filmforming co-solvent.This system effectively lowers the desolvation energy of Li^(+)through dipole-dipole interactions.The weak solvation capability allows more anions to enter the solvation sheath,promoting the formation of contact ion pairs(CIPs)and aggregates(AGGs)that enhance the transport rate of Li^(+)while maintaining high ionic conductivity across a broad temperature range.Moreover,the formation of inorganic-dominant interfacial phases on the graphite anode,induced by fluoroethylene carbonate,significantly enhances the kinetics of Li^(+)transport.At a low temperature of-20℃,this electrolyte system achieves an impressive reversible capacity of 200.9 mAh g^(-1)in graphite half-cell,which is nearly three times that observed with conventional EC-based electrolytes,demonstrating excellent stability throughout its operation. 展开更多
关键词 Lithium-ion batteries low-temperature electrolytes ISOXAZOLE Dipole-dipole interactions low desolvation energy
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Low Temperature Sintering of ZnAl_(2)O_(4) Ceramics with CuO-TiO_(2)-Nb_(2)O_(5) Composite Oxide Sintering Aid
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作者 YANG Yan ZHANG Faqiang +3 位作者 MA Mingsheng WANG Yongzhe OUYANG Qi LIU Zhifu 《无机材料学报》 北大核心 2025年第6期711-718,I0009-I0011,共11页
ZnAl_(2)O_(4) and ZnAl_(2)O_(4)-based ceramics have attracted much attention from researchers due to their good microwave dielectric,thermal and mechanical properties.In this work,the influence of 5%(in mass)CuO-TiO_(... ZnAl_(2)O_(4) and ZnAl_(2)O_(4)-based ceramics have attracted much attention from researchers due to their good microwave dielectric,thermal and mechanical properties.In this work,the influence of 5%(in mass)CuO-TiO_(2)-Nb_(2)O_(5)(CTN)ternary composite oxide additives with different composition ratios on sintering behavior and properties of ZnAl_(2)O_(4) microwave dielectric ceramics was investigated.When the molar fraction ranges of Cu,Ti and Nb elements in 5%CTN additives are 0.625-0.875,0-0.250 and 0.125-0.625,respectively,sintering temperature of ZnAl_(2)O_(4) ceramics can be reduced from above 1400℃to below 1000℃.The sintering additives CN(Cu:Nb=1:1,molar ratio)and CTN(Cu:Ti:Nb=4:1:3,molar ratio)can reduce sintering temperature of ZnAl_(2)O_(4) ceramics to 975 and 1000℃,respectively,while maintaining good dielectric properties(dielectric constantε_(r)=11.36,quality factor Q׃=8245 GHz andε_(r)=9.52,Q׃=22249 GHz)and flexural strengths(200 and 161 MPa),which are expected to be applied in preparation of low temperature co-fired ceramic(LTCC)materials with copper electrodes.Low-temperature sintering of the ZnAl_(2)O_(4)+CTN system is characterized as activated sintering.Nanometer-level amorphous interfacial films containing Cu,Ti,and Nb elements are observed at the grain boundaries,which may provide fast diffusion pathways for mass transportation during the sintering process.Valence changes of Ti and Cu ions,along with changes of oxygen vacancies,are confirmed,which provides a potential mechanism for reduced sintering temperature of ZnAl_(2)O_(4) ceramics.In addition,a series of reactions occurring at the grain boundaries can activate these boundaries and further promote the sintering densification process.These results suggest a promising way to design a novel LTCC material with excellent properties based on the low temperature sintering of ceramics with the sintering aid of CuO-TiO_(2)-Nb_(2)O_(5) composite oxide. 展开更多
关键词 ZnAl_(2)O_(4) CuO-TiO_(2)-Nb_(2)O_(5) low-temperature sintering microwave dielectric ceramic low temperature co-fired ceramic
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Effect of multidimensional nursing on low anterior resection syndrome after sphincter preservation surgery for low rectal cancer
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作者 Zheng Ruan Qun Ye Ran Yang 《World Journal of Gastrointestinal Surgery》 2025年第10期322-330,共9页
BACKGROUND According to the Global Cancer Statistics Report,the incidence of colorectal cancer ranks third and the mortality rate ranks second worldwide among malignant tumors.AIM To explore the effects of Nursing Out... BACKGROUND According to the Global Cancer Statistics Report,the incidence of colorectal cancer ranks third and the mortality rate ranks second worldwide among malignant tumors.AIM To explore the effects of Nursing Outcomes Classification(NOC)-based multidimensional nursing on self-efficacy and symptom relief in patients with low anterior resection syndrome(LARS)following sphincter-preserving surgery.METHODS This observational study enrolled 120 patients with LARS after sphincterpreserving surgery for low rectal cancer admitted to our hospital between January 2022 and December 2024.The patients were randomly divided into a control group(n=60)that received routine nursing intervention or an observation group(n=60)that received multidimensional nursing intervention.Before and after the intervention,the Chinese version of the Self-Management Efficacy Scale for Cancer Patients(SUPPH),the LARS scoring scale,and the European Organization for Research and Treatment of Cancer Quality of Life Core Scale(EORTC QLQC30)were used to evaluate the self-efficacy,symptom relief,and quality of life of the two patient groups,and the nursing satisfaction was compared between the groups.RESULTS After the intervention,both groups showed increased scores for each item on the SUPPH and EORTC QLQ-C30 scales compared with those before the intervention,whereas the LARS score showed a decreasing trend.Compared with the control group,the scores for each item of the SUPPH and EORTC QLQ-C30 scales in the observation group were significantly higher after the intervention,while the LARS score was significantly lower(all P<0.05).Nursing satisfaction was significantly higher in the observation group than in the control group(83.33%vs 95.00%,P<0.05).CONCLUSION Multidimensional NOC-based nursing improves self-efficacy,symptoms,quality of life,and satisfaction in patients with LARS.However,further research is needed to assess its long-term and comparative effectiveness. 展开更多
关键词 low rectal cancer SURGERY low anterior resection syndrome Multidimensional nursing SELF-EFFICACY SYMPTOMS
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Low-Altitude Aerial Information Network:Challenges and Solutions
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作者 Niu Zhisheng Wei Zhang Cao Lei 《China Communications》 2025年第9期I0002-I0004,共3页
Low-altitude economy opens up a completely new aerial space for economic growth by enabling brand new services such as fast logistics delivery,timely emergency rescue,and wide-area,high-definition environmental monito... Low-altitude economy opens up a completely new aerial space for economic growth by enabling brand new services such as fast logistics delivery,timely emergency rescue,and wide-area,high-definition environmental monitoring.This new space has many distinct features and therefore faces many new challenges compared with ground-and high-altitude-based information infrastructures.As a result,the rapid and mass development of unmanned aerial vehicles(UAVs)in low-altitude space will inevitably necessitate research on providing ultra-reliable,low-latency,high-capacity. 展开更多
关键词 unmanned aerial vehicles low latency challenges economic growth solutions unmanned aerial vehicles uavs ultra reliable low altitude economy
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Low cycle fatigue behavior and cyclic deformation mechanism of 2195 Al-Li alloy at low temperatures
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作者 Zijie Meng Cunsheng Zhang +4 位作者 Yingzhi Li Zhenyu Liu Zinan Cheng Liang Chen Guoqun Zhao 《Journal of Materials Science & Technology》 2025年第32期274-292,共19页
The low cycle fatigue(LCF)behaviors and cyclic deformation mechanisms of 2195 Al-Li alloy were inves-tigated under low temperatures(-20℃and-80℃)and different strain amplitudes(0.6%,0.7%,0.8%,and 1.0%).The LCF stress... The low cycle fatigue(LCF)behaviors and cyclic deformation mechanisms of 2195 Al-Li alloy were inves-tigated under low temperatures(-20℃and-80℃)and different strain amplitudes(0.6%,0.7%,0.8%,and 1.0%).The LCF stress responses under conditions of-20℃&0.6%and-80℃&0.6%exhibited initial cyclic hardening followed by cyclic softening.In contrast,the alloy under other LCF conditions displayed continuous cyclic softening.Notably,the alloy demonstrated reduced LCF life under conditions of-80℃and various strain amplitudes.The fatigue life model based on the total strain energy was developed and proven to be more accurate in predicting fatigue life under diverse LCF conditions.Furthermore,the combined kinematic/isotropic hardening constitutive model exhibited excellent performance in simulat-ing hysteresis loops of the alloy,with corresponding calibration errors all below 14%.Additionally,fatigue fracture surfaces under various LCF conditions consistently exhibited prominent cleavage fracture char-acteristics,and the final fracture zone at-80℃showed increased surface roughness.Finally,the cyclic softening mechanisms were found to be dependent on LCF conditions.The debonding of the interface be-tween the T1 phases and the Al matrix was identified as the primary cyclic softening mechanism under conditions of-20℃&0.6%and-80℃&0.6%.Moreover,the cyclic softening effect under-80℃&1.0%was closely associated with localized shearing of T1 phases.Under-20℃&1.0%,a more pronounced cyclic softening behavior was observed,which was primarily attributed to the continuous shearing of T1 phases. 展开更多
关键词 2195 Al-Li alloy low temperature low cycle fatigue behavior Hysteresis loop simulation Fatigue life prediction Cyclic deformation mechanism
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Right ventricular myocardial infarction due to low-voltage electric shock:a case report
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作者 Nalan Kozaci İhsan Danış +2 位作者 Ali Kemal Erenler Tayfun Anıl Demir Mustafa Avci 《Journal of Geriatric Cardiology》 2025年第12期995-997,共3页
Severe injuries due to electricity are rare,but when they occur,they may cause life-threatening conditions.In order to define the severity of electrical injuries,the most widely used classification is voltage power.In... Severe injuries due to electricity are rare,but when they occur,they may cause life-threatening conditions.In order to define the severity of electrical injuries,the most widely used classification is voltage power.Injuries are mainly classified into two categories as low voltage electrical injuries(LVEI)(<1000 V)and high voltage electrical injuries(>1000 V).Fatal injuries have been reported mostly after high-voltage electric shock.Low-voltage electricity current rarely causes severe trauma and complications. 展开更多
关键词 low voltage electrical injuries lvei high voltage electrical injuries voltage power right ventricular myocardial infarction low voltage electric shock classification electrical injuries severe electrical injuries define severity electrical injuriesthe
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A 5mW 1.8V Low Over-Sampling Ratio ΣΔ Modulator with 81dB Dynamic Range 被引量:2
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作者 徐栋麟 赵晖 +2 位作者 王照钢 任俊彦 闵昊 《Journal of Semiconductors》 EI CAS CSCD 北大核心 2004年第1期12-18,共7页
This work demonstrates that the ΣΔ modulator with a low oversampling ratio is a viable option for the high-resolution digitization in a low-voltage environment.Low power dissipation is achieved by designing a low-OS... This work demonstrates that the ΣΔ modulator with a low oversampling ratio is a viable option for the high-resolution digitization in a low-voltage environment.Low power dissipation is achieved by designing a low-OSR modulator based on differential cascade architecture,while large signal swing maintained to achieve a high dynamic range in the low-voltage environment.Operating from a voltage supply of 1.8V,the sixth-order cascade modulator at a sampling frequency of 4-MHz with an OSR of 24 achieves a dynamic range of 81dB for a 80-kHz test signal,while dissipating only 5mW. 展开更多
关键词 ∑△ modulator low over sampling ratio low power low voltage
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Automatic diagnosis of keratitis from low-quality slit-lamp images using feature vector quantization and self-attention mechanisms
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作者 JIANG Jiewei XIN Yu +3 位作者 DING Ke ZHU Mingmin CHEN Yi LI Zhongwen 《Optoelectronics Letters》 2025年第10期612-618,共7页
This paper proposes a novel method for the automatic diagnosis of keratitis using feature vector quantization and self-attention mechanisms(ADK_FVQSAM).First,high-level features are extracted using the DenseNet121 bac... This paper proposes a novel method for the automatic diagnosis of keratitis using feature vector quantization and self-attention mechanisms(ADK_FVQSAM).First,high-level features are extracted using the DenseNet121 backbone network,followed by adaptive average pooling to scale the features to a fixed length.Subsequently,product quantization with residuals(PQR)is applied to convert continuous feature vectors into discrete features representations,preserving essential information insensitive to image quality variations.The quantized and original features are concatenated and fed into a self-attention mechanism to capture keratitis-related features.Finally,these enhanced features are classified through a fully connected layer.Experiments on clinical low-quality(LQ)images show that ADK_FVQSAM achieves accuracies of 87.7%,81.9%,and 89.3% for keratitis,other corneal abnormalities,and normal corneas,respectively.Compared to DenseNet121,Swin transformer,and InceptionResNet,ADK_FVQSAM improves average accuracy by 3.1%,11.3%,and 15.3%,respectively.These results demonstrate that ADK_FVQSAM significantly enhances the recognition performance of keratitis based on LQ slit-lamp images,offering a practical approach for clinical application. 展开更多
关键词 KERATITIS low quality images adaptive average pooling densenet backbone networkfollowed self attention mechanism feature vector quantization diagnosis keratitis automatic diagnosis
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Interactions of the Background State and Eddies in Shaping Aleutian Low Variations
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作者 Nan LIN Tuantuan ZHANG +3 位作者 Qiaoling REN Ho-Nam CHEUNG Chang-Hoi HO Song YANG 《Advances in Atmospheric Sciences》 2025年第8期1548-1565,共18页
The Aleutian Low(AL)is a dominant feature of the mean circulation in the North Pacific during the winter season.The background stationary wave,air-sea interaction,and transient eddies over the North Pacific exert dist... The Aleutian Low(AL)is a dominant feature of the mean circulation in the North Pacific during the winter season.The background stationary wave,air-sea interaction,and transient eddies over the North Pacific exert distinct impacts on the interannual variations of the AL intensity and position.In this study,we adopt the quasi-geostrophic geopotential tendency equation to investigate the roles of various physical processes in the maintenance and interannual variations of this system.The results show that absolute vorticity advection plays the most important role in the formation and maintenance of AL intensity,while high-frequency transient eddies contribute most to the meridional and zonal shifts of the AL.The high-frequency transient eddy vorticity forcing affects the AL through the barotropic energy conversion process,and,in turn,the AL enhances the high-frequency transient eddies through the baroclinic energy conversion process,forming a positive feedback.The associated high-frequency eddy kinetic energy anomalies exhibit an eastward movement toward the east coast of North America in the years of an intensified AL,which explains why a strengthened AL is often accompanied by an eastward movement.Furthermore,the energy conversion terms of high-frequency transient eddies are mostly located over the extratropical eastern North Pacific,leading to asymmetric features in the zonal movement of the AL. 展开更多
关键词 Aleutian low interannual variations interactions between eddies and the background flow
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What a pain in the back:etiology,diagnosis and future treatment directions for discogenic low back pain
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作者 Giselle Kaneda Lea Zila +7 位作者 Jacob T.Wechsler Karim Shafi Karandeep Cheema Hyun Bae Sang D。Kim Alexander Tuchman Debiao Li Dmitriy Sheyn 《Bone Research》 2025年第5期1083-1110,共28页
Chronic lower back pain(LBP)is the leading cause of disability worldwide.Due to its close relationship with intervertebral disc(IVD)degeneration(IVDD),research has historically focused more on understanding the mechan... Chronic lower back pain(LBP)is the leading cause of disability worldwide.Due to its close relationship with intervertebral disc(IVD)degeneration(IVDD),research has historically focused more on understanding the mechanism behind IVDD while clinical efforts prioritize pain management.More recently,there has been a shift toward understanding LBP as a distinct pathological entity.This review synthesizes current knowledge on discogenic LBP,combining known pathophysiology,molecular mechanisms,risk factors,diagnostic challenges,and available experimental models.IVDD is a complex,multifactorial process involving biochemical,mechanical,and inflammatory changes within the disc,leading to structural breakdown and potential discogenic pain.Key mechanisms include extracellular matrix degradation,upregulation of inflammatory mediators,immune cell infiltration,and aberrant nerve and vascular ingrowth.However,not all cases of IVDD result in LBP,highlighting the need for further investigation into the cellular,molecular,and biomechanical factors contributing to symptom development.Current diagnostic tools and experimental models for studying discogenic LBP remain limited,impeding the development of targeted treatments.Existing therapies primarily focus on symptom management rather than addressing underlying disease mechanisms. 展开更多
关键词 intervertebral disc degeneration molecular mechanisms risk factors diagnostic challenges experimental models PATHOPHYSIOLOGY chronic lower back pain lbp discogenic low back pain
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Research on resonant ring-modified photonic crystal line-defect slow-light waveguide
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作者 LIU Qianzhen MA Chengju LI Yan 《Optoelectronics Letters》 2025年第7期419-426,共8页
This paper presents a photonic crystal(PhC)line-defect slow-light waveguide modified by resonant rings.We introduce resonant rings into the line defect,constructing a slow-light waveguide with high normalized delay ba... This paper presents a photonic crystal(PhC)line-defect slow-light waveguide modified by resonant rings.We introduce resonant rings into the line defect,constructing a slow-light waveguide with high normalized delay bandwidth product(NDBP)and low group velocity dispersion(GVD).We simulate,analyze,and optimize the structural parameters of this slow-light waveguide using the finite difference time domain(FDTD)method,theoretically achieving a maximum group index of 3.7,maximum bandwidth of 15.6 nm,and maximum NDBP of 0.4416 for slow-light effect.The resonant ring-modified PhC slow-light waveguide designed in this paper exhibits GVD lower than the order of 10^(−20)s^(2)/m over a normalized frequency range from 0.3554 to 0.4175.This study is expected to provide theoretical references for the study of slow-light buffering devices based on PhCs with high NDBP values. 展开更多
关键词 finite difference time domain fdtd methodtheoretically line defect slow light waveguide normalized delay bandwidth product resonant rings low group velocity dispersion gvd we resonant ringswe maximum ndb photonic crystal
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Approach and Strategy of Constructing Low-carbon Communities 被引量:3
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作者 陈江美 李志英 《Meteorological and Environmental Research》 CAS 2010年第7期97-101,共5页
The developing focus of low-carbon society is constructing low-carbon cities which are based on the construction of low-carbon communities.The main ways of constructing low-carbon communities conclude low carbonizatio... The developing focus of low-carbon society is constructing low-carbon cities which are based on the construction of low-carbon communities.The main ways of constructing low-carbon communities conclude low carbonization of planning and designing,low carbonization of construction materials,low carbonization of community environment,low carbonization of energy system,low carbonization of energy use and low carbonization of life style.The basic strategies of constructing low-carbon communities contain enhancing propaganda and education,strengthening technical innovation,cultivating low-carbon culture,advocating public participation and consolidating leadership in organizations. 展开更多
关键词 low-carbon economy low-carbon city low-carbon community APPROACH STRATEGY China
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An overview on nonlinear porous flow in low permeability porous media 被引量:5
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作者 Yanzhang Huang Zhengming Yang +1 位作者 Ying He Xuewu Wang 《Theoretical & Applied Mechanics Letters》 CAS 2013年第2期1-8,共8页
This paper gives an overview on nonlinear porous flow in low permeability porous media, reveals the microscopic mechanisms of flows, and clarifies properties of porous flow fluids. It shows that, deviating from Darcy... This paper gives an overview on nonlinear porous flow in low permeability porous media, reveals the microscopic mechanisms of flows, and clarifies properties of porous flow fluids. It shows that, deviating from Darcy's linear law, the porous flow characteristics obey a nonlinear law in a low-permeability porous medium, and the viscosity of the porous flow fluid and the permeability values of water and oil are not constants. Based on these characters, a new porous flow model, which can better describe low permeability reservoir~ is established. This model can describe various patterns of porous flow, as Darcy's linear law does. All the parameters involved in the model, having definite physical meanings, can be obtained directly from the experiments. 展开更多
关键词 low permeability porous media nonlinear porous flow porous flow equation porous flowfluid
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