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Seismicity of the San Francisco Volcanic Field of Northern Arizona
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作者 David S. Brumbaugh 《Journal of Earth Science and Engineering》 2012年第12期722-728,共7页
Seismicity in northern Arizona is concentrated in a northwest-southeast trending belt that stretches from the Utah border south to the edge of the Colorado Plateau. Located within this NASB (Northern Arizona Seismic ... Seismicity in northern Arizona is concentrated in a northwest-southeast trending belt that stretches from the Utah border south to the edge of the Colorado Plateau. Located within this NASB (Northern Arizona Seismic Belt) is the San Francisco volcanic field, classified by the United States Geological Survey as potentially active. The last volcanic event in the field was located at Sunset Crater and occurred less than 1,000 years ago. Eruption intervals in the volcanic field are of the same order of length of time. Seismic monitoring of the volcanic field area has improved greatly since 1985 with the establishment of new network seismic stations. This has allowed for a lowered threshold of detection of seismic events and improved location capabilities. As an example of the result of this improved ability to locate smaller tremors, two swarms have been identified in the field, the 2009 Halloween swarm near Sunset Crater volcano and the 2011 swarm near Flagstaff, the largest urban community in northern Arizona. 展开更多
关键词 MONITORING SEISMICITY VOLCANISM Sunset Crater San Francisco volcanic field.
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Longitudinal Evaluation of Hemiplegic Ankle Rehabilitation Efficacy by Wearable Inertial Sensor Systems with an Assortment of Machine Learning Algorithms
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作者 Robert LeMoyne Timothy Mastroianni 《Journal of Biomedical Science and Engineering》 2023年第9期121-131,共11页
With the amalgamation of wearable systems equipped with inertial sensors, such as a gyroscope, and machine learning a therapy regimen can be objectively quantified, and then the initial phase and final phase of a one ... With the amalgamation of wearable systems equipped with inertial sensors, such as a gyroscope, and machine learning a therapy regimen can be objectively quantified, and then the initial phase and final phase of a one year therapy regimen can be distinguished through machine learning. In the context of rehabilitation of a hemiplegic ankle, a longitudinal therapy regimen incorporating stretching and then a series of repetitions for raising and lowering the foot of the hemiplegic ankle can be applied over the course of a year. Using a smartphone equipped with an application to function as a wearable and wireless gyroscope platform mounted to the dorsum of the foot by an armband, the initial phase and final phase of a one year longitudinally applied therapy regimen can be objectively quantified and recorded for subsequent machine learning. Considerable classification accuracy is attained to distinguish between the initial phase and final phase by a support vector machine for a one year longitudinally applied hemiplegic ankle therapy regimen based on the gyroscope signal data obtained by a smartphone functioning as a wearable and wireless inertial sensor system. . 展开更多
关键词 Smartphone GYROSCOPE Machine Learning HEMIPARESIS Rehabilitation ANKLE Longitudinal Evaluation
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美国国家公园管理及遗迹保护探析 被引量:1
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作者 郝俊卿 《陕西地质》 2013年第1期76-79,共4页
如何借鉴国外国家公园建设的有益经验和教训,推动地质公园健康发展是我国地质公园建设当中面对的重要问题之一。在实地考察美国典型国家公园建设基础上,对美国国家公园的发展历程、规划管理和遗迹保护进行了分析,据此指出了我国国家地... 如何借鉴国外国家公园建设的有益经验和教训,推动地质公园健康发展是我国地质公园建设当中面对的重要问题之一。在实地考察美国典型国家公园建设基础上,对美国国家公园的发展历程、规划管理和遗迹保护进行了分析,据此指出了我国国家地质公园建设今后发展应在坚持保护性开发基础上,逐步完善公园规划设计的统一性和持久性,注重地质遗迹保护的制度严格性和体验开放性,以期为我国地质公园建设提供借鉴。 展开更多
关键词 地质公园 遗迹保护 公园管理 美国国家公园
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中国新近纪犀科化石的演化与气候环境变迁
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作者 邓涛 W.Downs 《地质学报》 EI CAS CSCD 北大核心 2002年第2期198-198,共1页
中国新近纪的犀科化石有广泛的分布,但以往的研究大多侧重于犀科化石的系统分类,较少涉及到这一重要类别的生态意义。本文试图发现这些犀科化石与环境的密切关系,为恢复这一时期陆地生态系统的演变过程提供新的依据。研究的材料包括中... 中国新近纪的犀科化石有广泛的分布,但以往的研究大多侧重于犀科化石的系统分类,较少涉及到这一重要类别的生态意义。本文试图发现这些犀科化石与环境的密切关系,为恢复这一时期陆地生态系统的演变过程提供新的依据。研究的材料包括中国从早中新世早期直到晚上新世晚期已知的全部犀科化石记录,共2亚科4族25个种。依据新近纪哺乳动物群单位(NMU)标定每个时期犀科的分异度、新记录和绝灭种。中国新近纪犀科化石的分异度变化显著,可划分为5个阶段,包括中中新世和晚中新世2个高分异期以及早中新世、晚中新世初期和上新世3个低分异期。 早中新世(NMU1~5)犀科的分异度非常低,占统治地位的是矮脚犀类。 展开更多
关键词 中新世 中国 犀科化石 气候环境变迁
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基于轨迹重构的城市路网OD估计方法 被引量:1
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作者 黎文皓 季彦婕 +3 位作者 戚心怡 卜卿 郑岳标 张凡 《东南大学学报(自然科学版)》 EI CAS CSCD 北大核心 2021年第6期1084-1093,共10页
为了提高城市路网OD估计精度,提出了一种基于自动车辆识别数据的宏微观OD估计框架.该框架将微观层的个体路径选择行为和宏观层的随机用户均衡(SUE)分配相结合,微观层通过粒子滤波器的重要性采样过程更新状态空间概率曲线来实现车辆轨迹... 为了提高城市路网OD估计精度,提出了一种基于自动车辆识别数据的宏微观OD估计框架.该框架将微观层的个体路径选择行为和宏观层的随机用户均衡(SUE)分配相结合,微观层通过粒子滤波器的重要性采样过程更新状态空间概率曲线来实现车辆轨迹重构,从而构建宏观层路径流约束;宏观层建立上层为广义最小二乘、下层为路径流修正的Logit随机用户均衡分配的OD估计双层规划模型.该方法在基于Sioux-Falls网络的VISSIM仿真模型上实现,通过VISSIM设置虚拟检测器来模拟现实环境中的自动车辆识别系统.结果显示,所提方法在各OD对估计中的平均绝对误差(MAE)均值为106.2辆/h,总需求百分比偏差(TDPD)均值为9.54%,相比较于非轨迹方法(MAE均值720.05辆/h,TDPD均值41.54%)有明显优势,在检测器覆盖率大于60%的条件下可以得到较为可靠的OD估计结果. 展开更多
关键词 自动车辆识别 轨迹重构 粒子滤波 双层规划 OD估计
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Evolution of Chinese Neogene Rhinocerotidae and Its Response to Climatic Variations 被引量:10
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作者 W.DOWNS 《Acta Geologica Sinica(English Edition)》 SCIE CAS CSCD 2002年第2期139-145,共7页
Chinese Neogene Rhinocerotidae has quite a complete record and its temporalrange is the Early Miocene to Late Pliocene. The samples include 25 species in 4 tribes of 2subfamilies. They are used as a foundation for the... Chinese Neogene Rhinocerotidae has quite a complete record and its temporalrange is the Early Miocene to Late Pliocene. The samples include 25 species in 4 tribes of 2subfamilies. They are used as a foundation for the study of the evolution of the family and itsrelation to climatic changes. Taxonomic diversity, new records and extinctions are estimated foreach Chinese Neogene mammal faunal unit (NMU). The diversity of Chinese Rhinocerotidae variesnoticeably throughout the Neogene and is recognized within five stages: the Middle Miocene and LateMiocene are stages of high diversity and the Early Miocene, early Late Miocene and Pliocene arestages of low diversity. Rhinocerotid diversity and morphology are closely related to environmentalfactors and particularly sensitive to changes in ambient temperature and humidity. Theinterpretation of climatic variation reflected in the evolution of Rhinocerotidae correspondsprecisely with the conclusions drawn from other workers and provides new evidence for research onthe Neogene terrestrial ecosystem in China. 展开更多
关键词 RHINOCEROTIDAE NEOGENE CLIMATE China
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Microbiome and pancreatic cancer: A comprehensive topic review of literature 被引量:8
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作者 Natalie Ertz-Archambault Paul Keim Daniel Von Hoff 《World Journal of Gastroenterology》 SCIE CAS 2017年第10期1899-1908,共10页
To review microbiome alterations associated with pancreatic cancer, its potential utility in diagnostics, risk assessment, and influence on disease outcomes.METHODSA comprehensive literature review was conducted by al... To review microbiome alterations associated with pancreatic cancer, its potential utility in diagnostics, risk assessment, and influence on disease outcomes.METHODSA comprehensive literature review was conducted by all-inclusive topic review from PubMed, MEDLINE, and Web of Science. The last search was performed in October 2016.RESULTSDiverse microbiome alterations exist among several body sites including oral, gut, and pancreatic tissue, in patients with pancreatic cancer compared to healthy populations.CONCLUSIONPilot study successes in non-invasive screening strategies warrant further investigation for future translational application in early diagnostics and to learn modifiable risk factors relevant to disease prevention. Pre-clinical investigations exist in other tumor types that suggest microbiome manipulation provides opportunity to favorably transform cancer response to existing treatment protocols and improve survival. 展开更多
关键词 Pancreatic Cancer Human microbiome Biomarkers CANCER Cancer screening tests Treatment effectiveness
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Physiological responses of artificial moss biocrusts to dehydration-rehydration process and heat stress on the Loess Plateau, China 被引量:8
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作者 BU Chongfeng WANG Chun +2 位作者 YANG Yongsheng ZHANG Li Matthew A BOWKER 《Journal of Arid Land》 SCIE CSCD 2017年第3期419-431,共13页
Ex-situ cultivation of biological soil crusts (biocrusts) is a promising technology to produce materials that can induce the recovery of biocrusts in the field for the purposes of preventing soil erosion and improvi... Ex-situ cultivation of biological soil crusts (biocrusts) is a promising technology to produce materials that can induce the recovery of biocrusts in the field for the purposes of preventing soil erosion and improving hydrological function in degraded ecosystems. However, the ability of artificially cultivated biocrusts to survive under adverse field conditions, including drought and heat stresses, is still relatively unknown. Mosses can bolster biocrust resistance to the stresses (e.g., drought and heat) and the resistance may be introduced prior to field cultivation. In this study, we subjected the well-developed artificial moss biocrusts (dominant species of Didjmodon vinealis (Brid.) Zand.) that we cultivated in the phytotron to a dehydration-rehydration experiment and also a heat stress experiment and measured the activities of protective enzymes (including peroxidase (POD), superoxide dismutase (SOD), and catalase (CAT)) and the contents of osmoregulatory substances (including soluble proteins and soluble sugars) and malondialdehyde (MDA, an indicator of oxidative stress) in the stem and leaf fragments of mosses. The results showed that, during the dehydration process, the activities of protective enzymes and the contents of osmoregulatory substances and MDA gradually increased with increasing duration of drought stress (over 13 days). During the rehydration process, values of these parameters decreased rapidly after 1 d of rehydration. The values then showed a gradual decrease for 5 days, approaching to the control levels. Under heat stress (45℃), the activities of protective enzymes and the content of soluble proteins increased rapidly within 2 h of heat exposure and then decreased gradually with increasing duration of heat exposure. In contrast, the contents of soluble sugars and MDA always increased gradually with increasing duration of heat exposure. This study indicates that artificial moss biocrusts possess a strong drought resistance and this resistance can be enhanced after a gradual dehydration treatment. This study also indicates that artificial moss biocrusts can only resist short-term heat stress (not long-term heat stress). These findings suggest that short-term heat stress or prolonged drought stress could be used to elevate the resistance of artificial moss biocrusts to adverse conditions prior to field reintroduction. 展开更多
关键词 dehydration-rehydration heat stress Didymodon vinealis (Brid.) Zand. RESISTANCE Loess Plateau
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Biomechanics of ankle giving way:A case report of accidental ankle giving way during the drop landing test 被引量:3
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作者 Yumeng Li Jupil Ko +2 位作者 Shuqi Zhang Cathleen N.Brown Kathy J.Simpson 《Journal of Sport and Health Science》 SCIE 2019年第5期494-502,共9页
Background:Several case studies observed that the lateral ankle sprain resulted from a sudden increase in ankle inversion accompanied by internal rotation.However,without sufficient ankle kinetics and muscle activity ... Background:Several case studies observed that the lateral ankle sprain resulted from a sudden increase in ankle inversion accompanied by internal rotation.However,without sufficient ankle kinetics and muscle activity information in the literature,the detailed mechanism of ankle sprain is still unrevealed.The purpose of our case report is to present 2 accidental ankle giving way incidents for participants with chronic ankle instability(CAI)and compare to their normal trials with data of kinematics,kinetics,and electromyography(EMG).Case description:Two young female participants accidentally experienced the ankle giving way when landing on a 25°lateral-tilted force plate.3 D kinematics,kinetics,and muscle activity were recorded for the lower extremity.Qualitative comparisons were made between the giving way trials and normal trials for joint angles,angular velocities,moments,centers of pressure and EMG linear envelopes.Results:One participant’s giving way trial displayed increased ankle inversion and internal rotation angles in the pre-landing phase and at initial contact compared to her normal trials.Another participant’s giving way trial exhibited greater hip abduction angles and delayed activation of the peroneus longus muscle in the pre-landing phase versus her normal trials.Conclusion:A vulnerable ankle position(i.e.,more inverted and internally rotated),and a late activation of peroneus activity in the pre-landing phase could result in the ankle giving way or even sprains.A neutral ankle position and early activation of ankle evertors before landing may be helpful in preventing ankle sprains. 展开更多
关键词 Chronic ANKLE instability EMG Kinematics Kinetics Lateral anlde SPRAIN
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Basic science and clinical use of eccentric contractions:History and uncertainties 被引量:2
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作者 Kiisa C.Nishikawa Stan L.Lindstedt Paul C.LaStayo 《Journal of Sport and Health Science》 SCIE 2018年第3期265-274,共10页
The peculiar attributes of muscles that are stretched when active have been noted for nearly a century.Understandably,the focus of muscle physiology has been primarily on shortening and isometric contractions,as eloqu... The peculiar attributes of muscles that are stretched when active have been noted for nearly a century.Understandably,the focus of muscle physiology has been primarily on shortening and isometric contractions,as eloquently revealed by A.V.Hill and subsequently by his students.When the sliding filament theory was introduced by A.F.Huxley and H.E.Huxley,it was a relatively simple task to link Hill's mechanical observations to the actions of the cross bridges during these shortening and isometric contractions.In contrast,lengthening or eccentric contractions have remained somewhat enigmatic.Dismissed as necessarily causing muscle damage,eccentric contractions have been much more difficult to fit into the cross-bridge theory.The relatively recent discovery of the giant elastic sarcomeric filament titin has thrust a previously missing element into any discussion of muscle function,in particular during active stretch.Indeed,the unexpected contribution of giant elastic proteins to muscle contractile function is highlighted by recent discoveries that twitchin-actin interactions are responsible for the"catch"property of invertebrate muscle.In this review,we examine several current theories that have been proposed to account for the properties of muscle during eccentric contraction.We ask how well each of these explains existing data and how an elastic filament can be incorporated into the sliding filament model.Finally,we review the increasing body of evidence for the benefits of including eccentric contractions into a program of muscle rehabilitation and strengthening. 展开更多
关键词 EXERCISE Force enhancement MUSCLE MECHANICS Rehabilitation Titin/connectin
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Wearable and wireless accelerometer systems for monitoring Parkinson’s disease patients—A perspective review 被引量:3
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作者 Robert LeMoyne 《Advances in Parkinson's Disease》 2013年第4期113-115,共3页
Parkinson’s disease is a growing medical concern as societies, such as the United States of America, become progressively aged. Therapy strategies exist for the amelioration of Parkinson’s disease symptoms, and the ... Parkinson’s disease is a growing medical concern as societies, such as the United States of America, become progressively aged. Therapy strategies exist for the amelioration of Parkinson’s disease symptoms, and the quantification of attributes, such as hand tremor, can provide valuable feedback. Wearable and wireless accelerometer systems for monitoring Parkinson’s disease patients have been progressively advanced over the course of the past half-decade. In particular, wireless accelerometer nodes and smartphones, such as the iPhone, hold promise for optimizing therapy strategy by providing convenient quantified feedback. This perspective review addresses the current advances in wearable and wireless accelerometer systems for monitoring Parkinson’s disease patients and forecasts for the near future. 展开更多
关键词 Parkinson’s DISEASE WIRELESS ACCELEROMETER Parkinson’s DISEASE TREMOR Quantification WEARABLE Device
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U.S. national parks accessibility and visitation 被引量:2
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作者 SHEN Xing-ju HUANG Rui-hong ZHANG Jin-shan 《Journal of Mountain Science》 SCIE CSCD 2019年第12期2894-2906,共13页
Accessibility is a factor affecting national park visitation.However,the effect of accessibility on national park visitation is not fully understood.This paper examines the relationship between U.S.national park visit... Accessibility is a factor affecting national park visitation.However,the effect of accessibility on national park visitation is not fully understood.This paper examines the relationship between U.S.national park visitation and accessibility.First,the global and local accessibility indexes of each park unit are computed based on an accessibility model that takes into account the surrounding population and its proximity to the park unit.Integrated in the model is a distance decay coefficient that is derived from U.S.national park visitor surveys and therefore pertinent to the case of study.Then correlation analysis is performed between park visitation and accessibility based on park types,regions,and visitation types.Results show that total visitation is positively related to accessibility in National Memorials,Military Parks and Battlefield Parks/Sites but negatively related to accessibility in national parks and national monuments.However,recreational overnight stay visits are commonly negatively correlated to accessibility for almost all park types.Moreover,local accessibility index displays enhanced correlation coefficients with improved significance levels in many categories of analysis.Results suggest that historical/cultural national parks which often show positive correlations tend to attract more local visitors,but nature-based parks which mainly show negative correlations tend to attract more distant visitors. 展开更多
关键词 U.S.National Park ACCESSIBILITY VISITATION Distance decay GIS
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The Future Common Ancestry of All Present-Day Humans 被引量:3
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作者 Philip M. Service 《Natural Science》 2021年第4期117-132,共16页
At some future time, each person alive today will be either an ancestor of everyone or an ancestor of no one. If the global population were unstructured by geography, race, religion and other factors, the time to futu... At some future time, each person alive today will be either an ancestor of everyone or an ancestor of no one. If the global population were unstructured by geography, race, religion and other factors, the time to future common ancestry for present-day humans would be between 33 and 66 generations, or about 1000 - 2000 years. In a structured population, migration and intermarriage are the necessary conditions for global common ancestry. Simulation of random and hierarchical migration models, shows that time to future global ancestry is generally less than triple, and often less than twice, that required for an unstructured population. The models suggest that someone alive today will become a common ancestor of the entire world population by about 5000 CE, or sooner;and that all current humans who are destined to become global common ancestors will be so by about 8000 CE, or sooner. At which time, everybody then alive will have the exact same genealogical ancestors from the present day. 展开更多
关键词 GENEALOGY Common Ancestry Human Population Structure Random Migration Hierarchical Migration
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Natural regeneration responses to thinning and burning treatments in ponderosa pine forests and implications for restoration 被引量:1
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作者 Tzeidle N.Wasserman Amy E.M.Waltz +2 位作者 John Paul Roccaforte Judith D.Springer Joseph E.Crouse 《Journal of Forestry Research》 SCIE CAS CSCD 2022年第3期741-753,共13页
Understanding naturally occurring pine regeneration dynamics in response to thinning and burning treatments is necessary not only to measure the longevity of the restoration or fuels treatment,but also to assess how w... Understanding naturally occurring pine regeneration dynamics in response to thinning and burning treatments is necessary not only to measure the longevity of the restoration or fuels treatment,but also to assess how well regeneration meets forest sustainability guidelines and whether natural regeneration is sufficient for maintaining a sustainable forest structure and composition.A synthesis review was carried out on the effects of mechanical thinning and prescribed burn treatments on natural pine regeneration response in frequent-fire ponderosa pine forests across the western United States.The focus was on site-specific variability in pine regeneration dynamics,temporal trends in regeneration presence and abundance,and response to treatment as described in the current literature using 29 studies that met our evidence-based review protocols.Data showed that the effects of thinning and burning treatments on regeneration depended on time since treatment.Mechanical thinning,prescribed burning,and thinning plus burn treatments all increased seedling density,but there was high variability among sites and studies.There were mixed results in the short-term(<10 years)with both increasing and decreasing regeneration,and a general increase in regeneration 11−20 years post-treatment.Some long-term studies(>20 years)concluded that stands can return to pre-treatment densities in terms of total trees per hectare and forest floor duff levels when there are no maintenance treatments applied.Several studies showed the average ponderosa pine seedling presence,survival and growth found in today’s forests to be at a high density;this combined with missed fire cycles could contribute to future fire risk and reduce the efficacy of maintaining fuel reduction goals. 展开更多
关键词 REGENERATION Ponderosa pine Frequent-fire TREATMENTS THINNING BURNING
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全球化视野下的中国旅游研究 被引量:1
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作者 Alan A.Lew 杨昀(译) 《旅游学刊》 CSSCI 2014年第1期3-6,共4页
20世纪70年代中期,我以本科交换生的身份来到香港学习,那是我第一次到中国。然而,当时我能到的距离中国大陆最近的地方就是香港新界的罗湖火车站。直到1984年,完成了新加坡的博士论文调研后,我本打算回美国,后终下定决心要到中国走一遭。
关键词 中国大陆 旅游研究 全球化视野 旅游发展 外视角 20世纪70年代 认知 国内
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Implementation of a Smartphone as a Wearable and Wireless Accelerometer and Gyroscope Platform for Ascertaining Deep Brain Stimulation Treatment Efficacy of Parkinson’s Disease through Machine Learning Classification 被引量:4
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作者 Robert LeMoyne Timothy Mastroianni +3 位作者 Cyrus McCandless Christopher Currivan Donald Whiting Nestor Tomycz 《Advances in Parkinson's Disease》 2018年第2期19-30,共12页
Parkinson’s disease manifests in movement disorder symptoms, such as hand tremor. There exists an assortment of therapy interventions. In particular deep brain stimulation offers considerable efficacy for the treatme... Parkinson’s disease manifests in movement disorder symptoms, such as hand tremor. There exists an assortment of therapy interventions. In particular deep brain stimulation offers considerable efficacy for the treatment of Parkinson’s disease. However, a considerable challenge is the convergence toward an optimal configuration of tuning parameters. Quantified feedback from a wearable and wireless system consisting of an accelerometer and gyroscope can be enabled through a novel software application on a smartphone. The smartphone with its internal accelerometer and gyroscope can record the quantified attributes of Parkinson’s disease and tremor through mounting the smartphone about the dorsum of the hand. The recorded data can be then wirelessly transmitted as an email attachment to an Internet derived resource for subsequent post-processing. The inertial sensor data can be consolidated into a feature set for machine learning classification. A multilayer perceptron neural network has been successfully applied to attain considerable classification accuracy between deep brain stimulation “On” and “Off” scenarios for a subject with Parkinson’s disease. The findings establish the foundation for the broad objective of applying wearable and wireless systems for the development of closed-loop optimization of deep brain stimulation parameters in the context of cloud computing with machine learning classification. 展开更多
关键词 Parkinson’s Disease Deep Brain Stimulation WEARABLE and WIRELESS Systems SMARTPHONE Machine Learning WIRELESS ACCELEROMETER WIRELESS GYROSCOPE Hand Tremor
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Multi-Feature Fusion-Guided Multiscale Bidirectional Attention Networks for Logistics Pallet Segmentation 被引量:1
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作者 Weiwei Cai Yaping Song +2 位作者 Huan Duan Zhenwei Xia Zhanguo Wei 《Computer Modeling in Engineering & Sciences》 SCIE EI 2022年第6期1539-1555,共17页
In the smart logistics industry,unmanned forklifts that intelligently identify logistics pallets can improve work efficiency in warehousing and transportation and are better than traditional manual forklifts driven by... In the smart logistics industry,unmanned forklifts that intelligently identify logistics pallets can improve work efficiency in warehousing and transportation and are better than traditional manual forklifts driven by humans.Therefore,they play a critical role in smart warehousing,and semantics segmentation is an effective method to realize the intelligent identification of logistics pallets.However,most current recognition algorithms are ineffective due to the diverse types of pallets,their complex shapes,frequent blockades in production environments,and changing lighting conditions.This paper proposes a novel multi-feature fusion-guided multiscale bidirectional attention(MFMBA)neural network for logistics pallet segmentation.To better predict the foreground category(the pallet)and the background category(the cargo)of a pallet image,our approach extracts three types of features(grayscale,texture,and Hue,Saturation,Value features)and fuses them.The multiscale architecture deals with the problem that the size and shape of the pallet may appear different in the image in the actual,complex environment,which usually makes feature extraction difficult.Our study proposes a multiscale architecture that can extract additional semantic features.Also,since a traditional attention mechanism only assigns attention rights from a single direction,we designed a bidirectional attention mechanism that assigns cross-attention weights to each feature from two directions,horizontally and vertically,significantly improving segmentation.Finally,comparative experimental results show that the precision of the proposed algorithm is 0.53%–8.77%better than that of other methods we compared. 展开更多
关键词 Logistics pallet segmentation image segmentation multi-feature fusion multiscale network bidirectional attention mechanism HSV neural networks deep learning
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Use of clinical movement screening tests to predict injury in sport 被引量:1
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作者 Nicole J Chimera Meghan Warren 《World Journal of Orthopedics》 2016年第4期202-217,共16页
Clinical movement screening tests are gaining popularity as a means to determine injury risk and to implement training programs to prevent sport injury. While these screens are being used readily in the clinical field... Clinical movement screening tests are gaining popularity as a means to determine injury risk and to implement training programs to prevent sport injury. While these screens are being used readily in the clinical field, it is only recently that some of these have started to gain attention from a research perspective. This limits applicability and poses questions to the validity, and in some cases the reliability, of the clinical movement tests as they relate to injury prediction, intervention, and prevention. This editorial will review the following clinical movement screening tests: Functional Movement Screen?, Star Excursion Balance Test, Y Balance Test, Drop Jump Screening Test, Landing Error Scoring System, and the Tuck Jump Analysis in regards to test administration, reliability, validity, factors that affect test performance, intervention programs, and usefulness for injury prediction. It is important to review the aforementioned factors for each of these clinical screening tests as this may help clinicians interpret the current body of literature. While each of these screening tests were developed by clinicians based on what appears to be clinical practice, this paper brings to light that this is a need for collaboration between clinicians and researchers to ensure validity of clinically meaningful tests so that they are used appropriately in future clinical practice. Further, this editorial may help to identify where the research is lacking and, thus, drive future research questions in regards to applicability and appropriateness of clinical movement screening tools. 展开更多
关键词 Functional MOVEMENT Screen Y BALANCE TEST Star EXCURSION BALANCE TEST TUCK JUMP analysis
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Calcite twinning strain variations across the Proterozoic Grenville orogen and Keweenaw-Kapuskasing inverted foreland,USA and Canada 被引量:1
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作者 John P.Craddock Suzanne D.Craddock +2 位作者 Alex Konstantinou Andrew R.C.Kylander-Clark David H.Malone 《Geoscience Frontiers》 SCIE CAS CSCD 2017年第6期1357-1384,共28页
We report the calcite twinning strain results of a traverse across the Grenville orogen from Parry Sound,Ontario(NW)to Ft.Ann,New York(SE),including the younger,adjacent Ordovician Taconic allochthon.Fifty four carbon... We report the calcite twinning strain results of a traverse across the Grenville orogen from Parry Sound,Ontario(NW)to Ft.Ann,New York(SE),including the younger,adjacent Ordovician Taconic allochthon.Fifty four carbonates(marbles,calcite veins,Ordovician limestone)were collected resulting in 68 strain analyses on mechanically twinned calcite(n=2337 grains)across the Central Gneiss Belt(CGB;3 samples),the Central Metasedimentary Belt(CMB;27 samples),the Central Granulite Terrane(CGT;Adirondack's;13 samples)and the Ottawan Orogenic Lid(OOL;11 samples).Twinning strains in the greenschist-grade OOL marbles preserve N-S shortening and U-Pb titanite ages(~1150 Ma;n=4)document these marbles formed during the Shawinigan(1190-1140 Ma)part of the Grenville orogen.From northwest to southeast,the Ottawan(1095-1020 Ma)twinning strain is dominantly a layerparallel shortening fabric oriented N-S(Parry Sound),then becomes parallel to the Grenville thrust direction(NW-SE)across the CMB to the Adirondack Highlands where the sub-horizontal shortening strain becomes margin-parallel(SW-NE).Within the regional sample suite there are two areas studied in detail,the Bancroft shear zone(n=11)and a roadcut on the southeast side of the Adirondack Mountains(Ft.Ann,NY;n=8).Marbles from the Bancroft shear zone contain calcite grains with 2 sets of twin lamellae(e_1 and e_2).The better-developed e_1 sets(n=406)record a horizontal fabric oriented NW-SE whereas the younger e_2 lamellae(n=146)preserve a margin-parallel(SW-NE)horizontal fabric.Both the e_1 and e_2 strains record an overprint vertical shortening strain(NEV),perhaps related to extensional orogenic collapse.We also report an Ottawan orogen-aged granoblastic mylonite(1093 Ma,U-Pb zircon;1102 Ma Ar-Ar biotite)in the Keweenaw thrust hanging wall 500 km inboard of the Grenville front and interpret the relations of Grenville-Keweenaw far-field dynamics. 展开更多
关键词 OROGENIC BELTS Strain PROTEROZOIC
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Pairwise Shared Ancestry in Random-Mating Constant-Size Populations 被引量:2
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作者 Philip M. Service 《Natural Science》 2022年第5期193-202,共10页
In a panmictic population of constant size N, random pairs of individuals will have a most recent shared ancestor who lived slightly more than 0.5 log<sub>2</sub>N generations previously, on average. The p... In a panmictic population of constant size N, random pairs of individuals will have a most recent shared ancestor who lived slightly more than 0.5 log<sub>2</sub>N generations previously, on average. The probability that a random pair of individuals will share at least one ancestor who lived 0.5 log<sub>2</sub>N generations ago, or more recently, is about 50%. Those individuals, if they do share an ancestor from that generation, would be cousins of degree (0.5 log<sub>2</sub>N) - 1. Shared ancestry from progressively earlier generations increases rapidly until there is universal pairwise shared ancestry. At that point, every individual has one or more ancestors in common with every other individual in the population, although different pairs may share different ancestors. Those ancestors lived approximately 0.7 log<sub>2</sub>N generations in the past, or more recently. Qualitatively, the ancestries of random pairs have about 50% similarity for ancestors who lived about 0.9 log<sub>2</sub>N generations before the present. That is, about half of the ancestors from that generation belonging to one member of the pair are present also in the genealogy of the other member. Qualitative pairwise similarity increases to more than 99% for ancestors who lived about 1.4 log<sub>2</sub>N generations in the past. Similar results apply to a metric of quantitative pairwise genealogical overlap. 展开更多
关键词 Pairwise Shared Ancestry Genealogical Overlap Quantitative Ancestry Most Recent Common Ancestor Number of Cousins
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