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Resolute支架在糖尿病患者复杂冠脉病变的应用
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作者 陈练 《中国医学前沿杂志(电子版)》 2012年第2期71-73,共3页
1病例资料 患者,男,54岁,汉族,河南省人,已婚。于2011年9月7日18:00入院,当日采集病史,患者本人陈述病史,可靠。主诉:阵发性心前区不适3月余。现病史:患者于2011年6月开始出现心前区不适症状,自觉与工作劳累有关,症状发作时无胸闷、胸... 1病例资料 患者,男,54岁,汉族,河南省人,已婚。于2011年9月7日18:00入院,当日采集病史,患者本人陈述病史,可靠。主诉:阵发性心前区不适3月余。现病史:患者于2011年6月开始出现心前区不适症状,自觉与工作劳累有关,症状发作时无胸闷、胸痛、心悸、乏力等不适,一般持续时间不超过5秒钟症状可自行缓解。患者平时长距离快步行走、爬楼时无明显症状,一般活动可。后就诊于当地医院行冠状动脉CT提示:前降支狭窄约50%。 展开更多
关键词 冠脉病变 resolute 对角支 糖尿病患者 支架 前降支
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澳大利亚Resolute矿山公司购买Xstrata黄金地产
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《中国有色冶金》 CAS 2004年第2期54-54,共1页
关键词 澳大利亚resolute矿山公司 黄金 地产 Xstrata公司
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Resolute Forest Products公司位于美国田纳西州Calhoun工厂的新卫生用纸生产线投产
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作者 陈京环 《造纸信息》 2017年第6期76-76,共1页
Resolute Forest Products公司近日宣布,成功启动其位于美国田纳西州Calhoun工厂的新卫生纸机,并已正式生产出第一个生活用纸母卷。
关键词 造纸业 行业信息 企业动态 resolute FOREST Products公司
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加拿大Resolute林产品公司转产生活用纸
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作者 王英斌 《造纸信息》 2017年第7期81-81,共1页
总部位于蒙特利尔的Resolute林产品公司(Resolute Forest Products)近日决定将调整其新闻纸生产业务。Resolute林产品公司是一家全球领先的林产品公司。其主要业务包括新闻纸、特种纸、商品浆与木制品等多种产品,是世界最大的新闻纸... 总部位于蒙特利尔的Resolute林产品公司(Resolute Forest Products)近日决定将调整其新闻纸生产业务。Resolute林产品公司是一家全球领先的林产品公司。其主要业务包括新闻纸、特种纸、商品浆与木制品等多种产品,是世界最大的新闻纸生产商。 展开更多
关键词 行业信息 造纸工业 resolute林产品公司 新闻纸
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Attempt to Resolute Chiral Clusters by Optically Active Hydrazide
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作者 Yu Hua ZHANG Wei Qiang ZHANG +4 位作者 Yu Gang CHEN Zhi CHEN Xin Yi ZHU Huan Wang JING Yuan Qi YIN 《Chinese Chemical Letters》 SCIE CAS CSCD 2001年第1期69-70,共2页
A new kind of hydrazone (I) diastereoisomers was prepared with enantiomeric hydazide (II) and chiral cluster (III), which was characterized by HMBC. Unfortunately, the mixture could not be separated into pure diastere... A new kind of hydrazone (I) diastereoisomers was prepared with enantiomeric hydazide (II) and chiral cluster (III), which was characterized by HMBC. Unfortunately, the mixture could not be separated into pure diastereoisomer. This could be a direction to separate the racemic chiral clusters. 展开更多
关键词 Chiral clusters optically active hydrazone chiral resolution DIASTEREOISOMER HMBC.
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基于多分支HRNet的图像篡改检测与定位模型 被引量:1
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作者 曾桢 谭平 《现代电子技术》 北大核心 2025年第3期35-42,共8页
传统的篡改方法如拷贝粘贴和拼接已演变为利用深度学习生成的高质量伪造图像,这些篡改技术在图像纹理和细节上留下难以察觉的痕迹,如高频噪声模式的异常、颜色分布的微妙变化,以及边缘区域的不自然过渡。这些痕迹分布在不同分辨率层次... 传统的篡改方法如拷贝粘贴和拼接已演变为利用深度学习生成的高质量伪造图像,这些篡改技术在图像纹理和细节上留下难以察觉的痕迹,如高频噪声模式的异常、颜色分布的微妙变化,以及边缘区域的不自然过渡。这些痕迹分布在不同分辨率层次和空间位置,增加了检测的难度。现有模型在整合多尺度和多位置特征时存在不足,难以有效捕捉局部细微纹理变化。针对这一问题,文中提出一种基于多分支HRNet的图像篡改检测与定位模型。该模型通过集成纹理增强模块,增强对图像篡改细节特征的捕获能力。同时,结合Spatial Weighting与Cross Resolution Weighting策略优化特征融合,并使用新的损失函数W_Arcloss,显著提升了模型在复杂篡改检测任务中的性能。在CASIA、Columbia、COVERAGE和NIST16等数据集上,该模型的检测准确度相较于PSCC⁃Net、HIFI⁃Net模型分别平均提升了6.5%与0.8%,并且泛化能力得到提升。这些结果证明了模型在处理多种篡改类型时的有效性和鲁棒性,为图像篡改检测与定位领域提供了新的研究视角和技术手段。 展开更多
关键词 图像篡改检测 深度学习 多分支HRNet 纹理增强模块 Spatial Weighting Cross Resolution Weighting W_Arcloss
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Fast-zoom and high-resolution sparse compound-eye camera based on dual-end collaborative optimization 被引量:1
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作者 Yi Zheng Hao-Ran Zhang +5 位作者 Xiao-Wei Li You-Ran Zhao Zhao-Song Li Ye-Hao Hou Chao Liu Qiong-Hua Wang 《Opto-Electronic Advances》 2025年第6期4-15,共12页
Due to the limitations of spatial bandwidth product and data transmission bandwidth,the field of view,resolution,and imaging speed constrain each other in an optical imaging system.Here,a fast-zoom and high-resolution... Due to the limitations of spatial bandwidth product and data transmission bandwidth,the field of view,resolution,and imaging speed constrain each other in an optical imaging system.Here,a fast-zoom and high-resolution sparse compound-eye camera(CEC)based on dual-end collaborative optimization is proposed,which provides a cost-effective way to break through the trade-off among the field of view,resolution,and imaging speed.In the optical end,a sparse CEC based on liquid lenses is designed,which can realize large-field-of-view imaging in real time,and fast zooming within 5 ms.In the computational end,a disturbed degradation model driven super-resolution network(DDMDSR-Net)is proposed to deal with complex image degradation issues in actual imaging situations,achieving high-robustness and high-fidelity resolution enhancement.Based on the proposed dual-end collaborative optimization framework,the angular resolution of the CEC can be enhanced from 71.6"to 26.0",which provides a solution to realize high-resolution imaging for array camera dispensing with high optical hardware complexity and data transmission bandwidth.Experiments verify the advantages of the CEC based on dual-end collaborative optimization in high-fidelity reconstruction of real scene images,kilometer-level long-distance detection,and dynamic imaging and precise recognition of targets of interest. 展开更多
关键词 compound-eye camera ZOOM high resolution collaborative optimization
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Advanced vat photopolymerization 3D printing of silicone rubber with high precision and superior stability 被引量:1
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作者 Zhongying Ji Bingang Xu +5 位作者 Zhiyong Su Xiaochen Wang Yang Lyu Sen Liu Tao Wu Xiaolong Wang 《International Journal of Extreme Manufacturing》 2025年第2期630-639,共10页
Silicone rubber(SR)is a versatile material widely used across various advanced functional applications,such as soft actuators and robots,flexible electronics,and medical devices.However,most SR molding methods rely on... Silicone rubber(SR)is a versatile material widely used across various advanced functional applications,such as soft actuators and robots,flexible electronics,and medical devices.However,most SR molding methods rely on traditional thermal processing or direct ink writing three-dimensional(3D)printing.These methods are not conducive to manufacturing complex structures and present challenges such as time inefficiency,poor accuracy,and the necessity of multiple steps,significantly limiting SR applications.In this study,we developed an SR-based ink suitable for vat photopolymerization 3D printing using a multi-thiol monomer.This ink enables the one-step fabrication of complex architectures with high printing resolution at the micrometer scale,providing excellent mechanical strength and superior chemical stability.Specifically,the optimized 3D printing SR-20 exhibits a tensile stress of 1.96 MPa,an elongation at break of 487.9%,and an elastic modulus of 225.4 kPa.Additionally,the 3D-printed SR samples can withstand various solvents(acetone,toluene,and tetrahydrofuran)and endure temperatures ranging from-50℃ to 180℃,demonstrating superior stability.As a emonstration of the application,we successfully fabricated a series of SR-based soft pneumatic actuators and grippers in a single step with this technology,allowing for free assembly for the first time.This ultraviolet-curable SR,with high printing resolution and exceptional stability performance,has significant potential to enhance the capabilities of 3D printing for applications in soft actuators,robotics,flexible electronics,and medical devices. 展开更多
关键词 3D printing silicone rubber high printing resolution pneumatic actuator
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CMOS direct conversion X-ray detector coupled with fluorinated liquid 被引量:1
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作者 Shi-Hua Liu Chao-Song Gao +5 位作者 Xin Zhang Xiang-Ming Sun Meng Wu Zhi-Hui Han Tong Wan Yong-Shuai Ge 《Nuclear Science and Techniques》 2025年第1期59-68,共10页
X-ray detectors show potential applications in medical imaging,materials science,and nuclear energy.To achieve high detection efficiency and spatial resolution,many conventional semiconductor materials,such as amorpho... X-ray detectors show potential applications in medical imaging,materials science,and nuclear energy.To achieve high detection efficiency and spatial resolution,many conventional semiconductor materials,such as amorphous selenium,cadmium telluride zinc,and perovskites,have been utilized in direct conversion X-ray detectors.However,these semiconductor materials are susceptible to temperature-induced performance degradation,crystallization,delamination,uneven lattice growth,radiation damage,and high dark current.This study explores a new approach by coupling an FC40 electronic fluorinated liquid with a specialized high-resolution and high-readout-speed complementary metal-oxide-semiconductor(CMOS)pixel array,specifically the Topmetal II−chip,to fabricate a direct conversion X-ray detector.The fluorinated liquid FC40(molecular formula:C_(21)F_(48)N_(2))is an electronic medium that is minimally affected by temperature and displays no issues with uniform conductivity.It exhibits a low dark current and minimal radiation damage and enables customizable thickness in X-ray absorption.This addresses the limitations inherent in conventional semiconductor-based detectors.In this study,simple X-ray detector imaging tests were conducted,demonstrating the excellent coupling capability between FC40 electronic fluorinated liquid and CMOS chips by the X-ray detector.A spatial resolution of 4.0 lp/mm was measured using a striped line par card,and a relatively clear image of a cockroach was displayed in the digital radiography imaging results.Preliminary test results indicated the feasibility of fabricating an X-ray detector by combining FC40 electronic fluorinated liquid and CMOS chips.Owing to the absence of issues related to chip-material coupling,a high spatial resolution could be achieved by reducing the chip pixel size.This method presents a new avenue for studies on novel liquid-based direct conversion X-ray detectors. 展开更多
关键词 FC40 electronic fluorinated liquid CMOS pixel chip X-ray detector Spatial resolution
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Pro-resolving lipid mediator reduces amyloid-β42–induced gene expression in human monocyte–derived microglia
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作者 Ying Wang Xiang Zhang +6 位作者 Henrik Biverstål Nicolas GBazan Shuai Tan Nailin Li Makiko Ohshima Marianne Schultzberg Xiaofei Li 《Neural Regeneration Research》 SCIE CAS 2025年第3期873-886,共14页
Specialized pro-resolving lipid mediators including maresin 1 mediate resolution but the levels of these are reduced in Alzheimer's disease brain, suggesting that they constitute a novel target for the treatment o... Specialized pro-resolving lipid mediators including maresin 1 mediate resolution but the levels of these are reduced in Alzheimer's disease brain, suggesting that they constitute a novel target for the treatment of Alzheimer's disease to prevent/stop inflammation and combat disease pathology. Therefore, it is important to clarify whether they counteract the expression of genes and proteins induced by amyloid-β. With this objective, we analyzed the relevance of human monocyte–derived microglia for in vitro modeling of neuroinflammation and its resolution in the context of Alzheimer's disease and investigated the pro-resolving bioactivity of maresin 1 on amyloid-β42–induced Alzheimer's disease–like inflammation. Analysis of RNA-sequencing data and secreted proteins in supernatants from the monocyte-derived microglia showed that the monocyte-derived microglia resembled Alzheimer's disease–like neuroinflammation in human brain microglia after incubation with amyloid-β42. Maresin 1 restored homeostasis by down-regulating inflammatory pathway related gene expression induced by amyloid-β42 in monocyte-derived microglia, protection of maresin 1 against the effects of amyloid-β42 is mediated by a re-balancing of inflammatory transcriptional networks in which modulation of gene transcription in the nuclear factor-kappa B pathway plays a major part. We pinpointed molecular targets that are associated with both neuroinflammation in Alzheimer's disease and therapeutic targets by maresin 1. In conclusion, monocyte-derived microglia represent a relevant in vitro microglial model for studies on Alzheimer's disease-like inflammation and drug response for individual patients. Maresin 1 ameliorates amyloid-β42–induced changes in several genes of importance in Alzheimer's disease, highlighting its potential as a therapeutic target for Alzheimer's disease. 展开更多
关键词 Alzheimer's disease amyloid-β maresin MICROGLIA MONOCYTE NEUROINFLAMMATION resolution RNA-sequencing specialized pro-resolving lipid mediator
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A high-resolution lithospheric magnetic field model of China and surroundings by using CHAMP,Swarm,CSES-1,and MSS-1 satellite magnetic measurements and aeromagnetic anomaly data 被引量:1
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作者 Pan Zhang JinSong Du +5 位作者 Liang Yin Qing Yan JiaXuan Zhang HouPu Li Keke Zhang Chao Chen 《Earth and Planetary Physics》 2025年第3期686-696,共11页
The CUG_CLMFM3D series comprises high-resolution three-dimensional lithospheric magnetic field models for China and its surroundings.The first version,CUG_CLMFM3Dv1,is a spherical cap harmonic model integrating the WD... The CUG_CLMFM3D series comprises high-resolution three-dimensional lithospheric magnetic field models for China and its surroundings.The first version,CUG_CLMFM3Dv1,is a spherical cap harmonic model integrating the WDMAMv2(World Digital Magnetic Anomaly Map version 2)global magnetic anomaly grid and nearly a decade of CHAMP(Challenging Minisatellite Payload for Geophysical Research and Application)satellite vector data.It achieves a~5.7 km resolution but has limitations:the WDMAMv2 grid lacks high-resolution data in the southern Xinjiang and Tibet regions,which leads to missing small-to medium-scale anomalies,and unfiltered CHAMP data introduce low-frequency conflicts with global spherical harmonic models.Above the altitude of 150 km,correlations with global models drop below 0.9.The second version,CUG_CLMFM3Dv2,addresses these issues by incorporating 5-km-resolution aeromagnetic data and rigorously processed satellite data from CHAMP,Swarm,CSES-1(China Seismo-Electromagnetic Satellite 1),and MSS-1(Macao Science Satellite 1).The comparison analysis shows that the CUG_CLMFM3Dv2 captures finer high-frequency details and more stable long-wavelength signals,offering improved magnetic anomaly maps for further geological and geophysical studies. 展开更多
关键词 Macao Science Satellite 1 China Seismo-Electromagnetic Satellite 1 revised spherical cap harmonic analysis high resolution lithospheric magnetic field China and surroundings
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Unbiased test of the hyperon CP violation in terms of detector resolution at STCF
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作者 Ming Xu Liang Liu +2 位作者 Yupeng Pei Xiaorong Zhou Yingchun Zhu 《中国科学技术大学学报》 北大核心 2025年第4期41-47,40,I0002,共9页
The study of the charge conjugation and parity(CP)violation of hyperon is the precision frontier for probing possible new CP violation sources beyond the standard model(SM).With the large number of quantum entangled h... The study of the charge conjugation and parity(CP)violation of hyperon is the precision frontier for probing possible new CP violation sources beyond the standard model(SM).With the large number of quantum entangled hyperonantihyperon pairs to be produced at Super Tau-Charm Facility(STCF),the CP asymmetry of hyperon is expected to be tested with a statistical sensitivity of 10^(−4) or even better.To cope with the statistical precision,the systematic effects from various aspects are critical and need to be studied in detail.In this paper,the sensitivity effects on the CP violation parameters associated with the detector resolution,including those of the position and momentum,are studied and discussed in detail.The results provide valuable guidance for the design of STCF detector. 展开更多
关键词 BESIII experiment STCF hyperon CP violation detector resolution unbiased test
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Infrared-NeRF:a low resolution thermal infrared light field 3D reconstruction method based on NeRF
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作者 HUANG Yi-Fan WANG Rui +2 位作者 DENG Li-Ming LI Jia-Jia LI Xi-Cai 《红外与毫米波学报》 北大核心 2025年第4期605-616,共12页
This article proposes a three-dimensional light field reconstruction method based on neural radiation field(NeRF)called Infrared NeRF for low resolution thermal infrared scenes.Based on the characteristics of the low ... This article proposes a three-dimensional light field reconstruction method based on neural radiation field(NeRF)called Infrared NeRF for low resolution thermal infrared scenes.Based on the characteristics of the low resolution thermal infrared imaging,various optimizations have been carried out to improve the speed and accuracy of thermal infrared 3D reconstruction.Firstly,inspired by Boltzmann's law of thermal radiation,distance is incorporated into the NeRF model for the first time,resulting in a nonlinear propagation of a single ray and a more accurate description of the physical property that infrared radiation intensity decreases with increasing distance.Secondly,in terms of improving inference speed,based on the phenomenon of high and low frequency distribution of foreground and background in infrared images,a multi ray non-uniform light synthesis strategy is proposed to make the model pay more attention to foreground objects in the scene,reduce the distribution of light in the background,and significantly reduce training time without reducing accuracy.In addition,compared to visible light scenes,infrared images only have a single channel,so fewer network parameters are required.Experiments using the same training data and data filtering method showed that,compared to the original NeRF,the improved network achieved an average improvement of 13.8%and 4.62%in PSNR and SSIM,respectively,while an average decreases of 46%in LPIPS.And thanks to the optimization of network layers and data filtering methods,training only takes about 25%of the original method's time to achieve convergence.Finally,for scenes with weak backgrounds,this article improves the inference speed of the model by 4-6 times compared to the original NeRF by limiting the query interval of the model. 展开更多
关键词 neural radiation field 3D reconstruction thermal infrared NeRF foreground segmentation low resolution
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Do Higher Horizontal Resolution Models Perform Better?
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作者 Shoji KUSUNOKI 《Advances in Atmospheric Sciences》 2026年第1期259-262,共4页
Climate model prediction has been improved by enhancing model resolution as well as the implementation of sophisticated physical parameterization and refinement of data assimilation systems[section 6.1 in Wang et al.(... Climate model prediction has been improved by enhancing model resolution as well as the implementation of sophisticated physical parameterization and refinement of data assimilation systems[section 6.1 in Wang et al.(2025)].In relation to seasonal forecasting and climate projection in the East Asian summer monsoon season,proper simulation of the seasonal migration of rain bands by models is a challenging and limiting factor[section 7.1 in Wang et al.(2025)]. 展开更多
关键词 enhancing model resolution refinement data assimilation systems section climate model climate projection higher horizontal resolution seasonal forecasting simulation seasonal migration rain bands model resolution
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Modeling and resolution analysis of microcylinder-assisted microscopy in reflection and transmission modes
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作者 Felix Rosenthal Tobias Pahl +4 位作者 Lucie Hüser Michael Diehl Tim Eckhardt Sebastian Hagemeier Peter Lehmann 《Advanced Photonics Nexus》 2025年第4期22-33,共12页
Microsphere and microcylinder-assisted microscopy(MAM)has grown steadily over the last decade and is still an intensively studied optical far-field imaging technique that promises to overcome the fundamental lateral r... Microsphere and microcylinder-assisted microscopy(MAM)has grown steadily over the last decade and is still an intensively studied optical far-field imaging technique that promises to overcome the fundamental lateral resolution limit of microscopy.However,the physical effects leading to resolution enhancement are still frequently debated.In addition,various configurations of MAM operating in transmission mode as well as reflection mode are examined,and the results are sometimes generalized.We present a rigorous simulation model of MAM and introduce a way to quantify the resolution enhancement.The lateral resolution is compared for microscope arrangements in reflection and transmission modes.Furthermore,we discuss different physical effects with respect to their contribution to resolution enhancement.The results indicate that the effects impacting the resolution in MAM strongly depend on the arrangement of the microscope and the measurement object.As a highlight,we outline that evanescent waves in combination with whispering gallery modes also improve the imaging capabilities,enabling super-resolution under certain circumstances.This result is contrary to the conclusions drawn from previous studies,where phase objects have been analyzed,and thus further emphasizes the complexity of the physical mechanisms underlying MAM. 展开更多
关键词 microsphere-assisted microscopy resolution enhancement resolution limit electromagnetic modeling SUPER-RESOLUTION whispering gallery mode
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Very Low Earth Orbit Satellites Promise Greater Resolution...and Less Privacy
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作者 Chris Palmer 《Engineering》 2025年第3期6-8,共3页
In February 2025,a startup satellite manufacturer,Albedo(Broomfield,CO,USA)is expected to launch its first satellite,Clarity-1,into orbit aboard SpaceX’s Transporter-13,a Falcon 9 rideshare mission[1].Like many imagi... In February 2025,a startup satellite manufacturer,Albedo(Broomfield,CO,USA)is expected to launch its first satellite,Clarity-1,into orbit aboard SpaceX’s Transporter-13,a Falcon 9 rideshare mission[1].Like many imaging satellites,Clarity-1’s mis-sion will be to take high-resolution aerial photos for clients in var-ious economic sectors including agriculture,insurance,energy,mapping,utilities,and defense.What makes this satellite unique is both its industry-leading 10 cm spatial resolution and its extre-mely low orbit of 200 km,far closer to Earth than the 450 km or higher orbits of most of its peers with similar missions. 展开更多
关键词 imaging satellitesclarity s spatial resolution high resolution imaging satellites low earth orbit aerial photos
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Adjusting the significance of daily climate responses in tree-ring proxies
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作者 Max C.A.Torbenson James H.Stagge +2 位作者 Feng Chen Emanuele Ziaco Jan Esper 《Journal of Forestry Research》 2025年第1期259-274,共16页
Correlating tree-ring parameters with daily resolved climate data is becoming increasingly common for understanding the complex relationships between tree growth and the surrounding environment.However,with an increas... Correlating tree-ring parameters with daily resolved climate data is becoming increasingly common for understanding the complex relationships between tree growth and the surrounding environment.However,with an increased number of calculated correlations,there is an inherent risk of spurious significance.In this study,we present an analysis using synthetic weather and tree-ring data mimicking the statistical properties of ten real-world sites across Europe to quantify the extent to which numerous comparisons may inflate maximum correlations.Comparisons of different tree-ring proxies,considering varying overlapping period lengths and seasons,revealed 95th percentile correlation differences reaching 0.25 by chance.Using synthetic tree-ring chronologies with an assigned non-signal(r=0.00),spurious correlations can reach statistical significance in over 60%of tests.Correlation inflation is greater when:(1)the climate-proxy relationship is weaker;(2)comparison periods are shorter;and(3)the length of seasonal windows is longer.Autocorrelation in the proxy records does not appear to have a major effect.These findings indicate that caution should be exercised when computing high numbers of correlations with limited observations.We provide tables listing correlation inflations for precipitation-and temperature-sensitive tree-ring chronologies that can inform interpretations of significance. 展开更多
关键词 DENDROCLIMATOLOGY Signal-noise Daily resolution SIGNIFICANCE Uncertainty
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Absorption compensation via structure tensor regularization multichannel inversion
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作者 Liang Bing Zhao Dong-feng +4 位作者 Xia Lian-jun Tang Guo-song Luo Zhen Guan Wen-hua Wang Xue-jing 《Applied Geophysics》 2025年第3期635-646,892,893,共14页
Absorption compensation is a process involving the exponential amplification of reflection amplitudes.This process amplifies the seismic signal and noise,thereby substantially reducing the signal-tonoise ratio of seis... Absorption compensation is a process involving the exponential amplification of reflection amplitudes.This process amplifies the seismic signal and noise,thereby substantially reducing the signal-tonoise ratio of seismic data.Therefore,this paper proposes a multichannel inversion absorption compensation method based on structure tensor regularization.First,the structure tensor is utilized to extract the spatial inclination of seismic signals,and the spatial prediction filter is designed along the inclination direction.The spatial prediction filter is then introduced into the regularization condition of multichannel inversion absorption compensation,and the absorption compensation is realized under the framework of multichannel inversion theory.The spatial predictability of seismic signals is also introduced into the objective function of absorption compensation inversion.Thus,the inversion system can effectively suppress the noise amplification effect during absorption compensation and improve the recovery accuracy of high-frequency signals.Synthetic and field data tests are conducted to demonstrate the accuracy and effectiveness of the proposed method. 展开更多
关键词 Absorption compensation Structure tensor RESOLUTION Signal-to-noise ratio REGULARIZATION
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Underlying mechanism of the topographic factor scale effect in soil erosion equations
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作者 ZHANG Qianyi JIANG Jiale SU Qi 《Journal of Mountain Science》 2025年第7期2574-2585,共12页
The topographic factor(LS factor),derived from the multiplication of the slope length(L)and slope steepness(S)factors,is a vital parameter in soil erosion models.Generated from the digital elevation model(DEM),the LS ... The topographic factor(LS factor),derived from the multiplication of the slope length(L)and slope steepness(S)factors,is a vital parameter in soil erosion models.Generated from the digital elevation model(DEM),the LS factor always varies with the changing DEM resolution,i.e.,the LS factor scale effect.Previous studies have found the phenomenon of the LS factor scale effect,but the underlying causes of this phenomenon has not been well explored.Therefore,how the DEM resolution affects the LS factor and how the scale effect of the L and S factors influence the LS factor scale effect remains unclear.To address these problems,we collected 20 watersheds from the Guangdong Province with different topographic reliefs,and compared the corresponding L,S and LS factors at 10-m and 30-m resolution DEMs.Our results indicate that the S factor,heavily influenced by slope underestimation in coarse-resolution DEMs,makes a difference in the LS factor scale effect.In addition,the LS factor scale effect becomes less significant with increasing reliefs,suggesting the possibility of using 30-m DEM for LS calculation in rugged terrains.Our findings on the underlying mechanisms of the LS factor scale effect help to identify the uncertainty in the LS factor estimation,thereby enhancing the accuracy of soil erosion assessment,particularly in regions with different topographic characteristics and contribute to more effective soil conservation strategies and decision-making. 展开更多
关键词 Topographic factor Scale effect Soil erosion DEM RESOLUTION
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Gamma-ray spectral energy resolution calibration based on locally constrained regularization for scintillation detector response:methodology,numerical,and experimental analysis
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作者 Guo-Feng Yang Wen-Zheng Peng +3 位作者 Dong-Ming Liu Xiao-Long Wu Meng Chen Xiang-Jun Liu 《Nuclear Science and Techniques》 2025年第4期92-104,共13页
Energy resolution calibration is crucial for gamma-ray spectral analysis,as measured using a scintillation detector.A locally constrained regularization method was proposed to determine the resolution calibration para... Energy resolution calibration is crucial for gamma-ray spectral analysis,as measured using a scintillation detector.A locally constrained regularization method was proposed to determine the resolution calibration parameters.First,a Monte Carlo simulation model consistent with an actual measurement system was constructed to obtain the energy deposition distribution in the scintillation crystal.Subsequently,the regularization objective function is established based on weighted least squares and additional constraints.Additional constraints were designed using a special weighting scheme based on the incident gamma-ray energies.Subsequently,an intelligent algorithm was introduced to search for the optimal resolution calibration parameters by minimizing the objective function.The most appropriate regularization parameter was determined through mathematical experiments.When the regularization parameter was 30,the calibrated results exhibited the minimum RMSE.Simulations and test pit experiments were conducted to verify the performance of the proposed method.The simulation results demonstrate that the proposed algorithm can determine resolution calibration parameters more accurately than the traditional weighted least squares,and the test pit experimental results show that the R-squares between the calibrated and measured spectra are larger than 0.99.The accurate resolution calibration parameters determined by the proposed method lay the foundation for gamma-ray spectral processing and simulation benchmarking. 展开更多
关键词 Energy resolution REGULARIZATION Gaussian broadening Spectral analysis Scintillation detector
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