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A Collaborative Broadcast Content Recording System Using Distributed Personal Video Recorders
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作者 Eunsam Kim Choonhwa Lee 《Computers, Materials & Continua》 2025年第2期2555-2581,共27页
Personal video recorders (PVRs) have altered the way users consume television (TV) content by allowing users to record programs and watch them at their convenience, overcoming the constraints of live broadcasting. How... Personal video recorders (PVRs) have altered the way users consume television (TV) content by allowing users to record programs and watch them at their convenience, overcoming the constraints of live broadcasting. However, standalone PVRs are limited by their individual storage capacities, restricting the number of programs they can store. While online catch-up TV services such as Hulu and Netflix mitigate this limitation by offering on-demand access to broadcast programs shortly after their initial broadcast, they require substantial storage and network resources, leading to significant infrastructural costs for service providers. To address these challenges, we propose a collaborative TV content recording system that leverages distributed PVRs, combining their storage into a virtual shared pool without additional costs. Our system aims to support all concurrent playback requests without service interruption while ensuring program availability comparable to that of local devices. The main contributions of our proposed system are fourfold. First, by sharing storage and upload bandwidth among PVRs, our system significantly expands the overall recording capacity and enables simultaneous recording of multiple programs without the physical constraints of standalone devices. Second, by utilizing erasure coding efficiently, our system reduces the storage space required for each program, allowing more programs to be recorded compared to traditional replication. Third, we propose an adaptive redundancy scheme to control the degree of redundancy of each program based on its evolving playback demand, ensuring high-quality playback by providing sufficient bandwidth for popular programs. Finally, we introduce a contribution-based incentive policy that encourages PVRs to actively participate by contributing resources, while discouraging excessive consumption of the combined storage pool. Through extensive experiments, we demonstrate the effectiveness of our proposed collaborative TV program recording system in terms of storage efficiency and performance. 展开更多
关键词 Collaborative recording TV content personal video recorder erasure coding REPLICATION
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An Effective Method to Determine the Distribution Boundary of Cobalt-Rich Fe-Mn Crusts on a Guyot: Synchronous Application of Sub-bottom Profiling and Deep-Sea Video Recording 被引量:3
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作者 HeGaowen LiangDonghong +4 位作者 SongChengbin SunXiaoming WuShuigen ZhouJianping ZhangXuehua 《Journal of China University of Geosciences》 SCIE CSCD 2005年第2期178-182,共5页
Determining the upper boundary of the cobalt-rich crust distribution of a guyot is important for estimating the mineral resources available, however, it has also long been an unsolved question. Correlations between th... Determining the upper boundary of the cobalt-rich crust distribution of a guyot is important for estimating the mineral resources available, however, it has also long been an unsolved question. Correlations between the sub-bottom structures, revealed by sub-bottom profiling, and crust distribution can be revealed for the first time by the synchronous application of sub-bottom profiling and deep-sea video recording. The lower boundary of the sediment corresponds with the upper boundary of the crust. By analysis of these two kinds of data, the lower boundary of the sediment can be determined; therefore, the upper boundary of the crust distribution can be deduced. According to this method of analysis, the upper boundary of water depth of crust distribution of a seamount in the western Pacific is about 1 560 m. 展开更多
关键词 sub-bottom profiling deep-sea video recording guyot cobalt-rich ferromanganese crust distribution boundary
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Patient interest in video recording of colonoscopy:A survey
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作者 Meghana Raghavendra Douglas K Rex 《World Journal of Gastroenterology》 SCIE CAS CSCD 2010年第4期458-461,共4页
AIM:To find if patients are interested in obtaining a video recording of their colonoscopy procedure.METHODS:We conducted a survey of outpatients presenting for colonoscopy regarding their interest in obtaining a vide... AIM:To find if patients are interested in obtaining a video recording of their colonoscopy procedure.METHODS:We conducted a survey of outpatients presenting for colonoscopy regarding their interest in obtaining a video recording of their colonoscopy.RESULTS:Two hundred and forty-eight patients(mean age 57.9 years;57% male) were surveyed.Two hundred and one patients(81%) were interested in obtaining a video recording.No significant predictors of patients' interest in the video recording were identified.After reading a brief educational paragraph explaining missed lesions during colonoscopy,135 patients(54%) were more interested in having a video recording,and none were less interested.One hundred and fifty-six patients(63%) were willing to pay for a video recording.In multivariable analyses,younger age was predictive of willingness to pay for a video recording.Prior history of colorectal cancer and a family history of colorectal cancer were predictive of willingness to pay a greater amount.CONCLUSION:Patients undergoing colonoscopy expressed substantial interest in obtaining a videorecording of their procedure.Awareness of missing lesions during colonoscopy increased interest in having a videorecording. 展开更多
关键词 COLONOSCOPY video recording SURVEY
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Should Audio and Video Recordings for Public Safety in a Ride-Sharing Vehicle Be Allowed?
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《ChinAfrica》 2018年第7期12-13,共2页
关键词 video recordings Public Safety
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Video recording of neonatal resuscitation:A feasibility study to inform widespread adoption
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作者 Sandesh Shivananda Jennifer Twiss +4 位作者 Enas el-Gouhary Salhabel-Helou Connie Williams Prashanth Murthy Gautham Suresh 《World Journal of Clinical Pediatrics》 2017年第1期69-80,共12页
AIM To determine the feasibility of introducing video recording(VR) of neonatal resuscitation(NR) in a perinatal centre.METHODS This was a prospective cohort quality improvement study on preterm infants and their care... AIM To determine the feasibility of introducing video recording(VR) of neonatal resuscitation(NR) in a perinatal centre.METHODS This was a prospective cohort quality improvement study on preterm infants and their caregivers.Based on evidence and experience of other centers using VR intervention,a contextually relevant implementation and evaluation strategy was designed in the planning phase.The components of intervention were pre-resuscitation team huddle,VR of NR and video debriefing(VD),all occurringon the same day.Various domains of feasibility and sustainability as well as feasibility criteria were predefined.Data for analysis was collected using quantitative and qualitative methods.RESULTS Seventy-one caregivers participated in VD of 14 NRs facilitated by six trained instructors.Ninety-one percent of caregivers perceived enhanced learning and patient safety and,48 issues were identified related to policy,caregiver roles,and latent safety threats.Ninety percent of caregivers expressed their willingness to participate in VD activity and supported the idea of integrating it into a resuscitation team routine.Eighty-three percent and 50% of instructors expressed satisfaction with video review software and quality of audio VR.No issues about maintenance of infant or caregivers' confidentiality and erasure of videos were reported.Criteria for feasibility were met(refusal rate of < 10%,VR performed on > 50% of occasions,and < 20% caregivers' perceiving a negative impact on team performance).Necessary adaptations to enhance sustainability were identified.CONCLUSION VR of NR as a standard of care quality assurance activity to enhance caregivers' learning and create opportunities that improve patient safety is feasible.Despite its complexity with inherent challenges in implementation,the intervention was acceptable,implementable,and potentially sustainable with adaptations. 展开更多
关键词 video recording NEONATAL RESUSCITATION Delivery room Feasibility PERINATAL centre
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Wireless capsule video endoscopy:Three years of experience 被引量:7
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作者 Rami Eliakim 《World Journal of Gastroenterology》 SCIE CAS CSCD 2004年第9期1238-1239,共2页
AIM:To review and summerize the current literatue regarding M2A wireless capsule endoscopy. METHODS:Peer reviewed publications regarding the use of capsule endoscopy as well as our personal experience were reviewed. R... AIM:To review and summerize the current literatue regarding M2A wireless capsule endoscopy. METHODS:Peer reviewed publications regarding the use of capsule endoscopy as well as our personal experience were reviewed. RESULTS:Review of the literature dearly showed that capsule endoscopy was superior to enteroscopy,small bowel follow through and computerized tomography in patients with obscure gastrointestinal bleeding,iron deficiency anemia, or suspected Crohn's disease.It was very sensitive for the diagnosis of small bowel tumors and for survailance of small bowel pathology in patients with Gardner syndrome or familial adenomatous polyposis syndrome.Its role in celiac disease and in patients with known Crohn's disease was currently being investigated. CONCLUSION:Capsule video endoscopy is a superior and more sensitive diagnostic tool than barium follow through, enteroscopy and entero-CT in establishing the diagnosis of many small bowel pathologies. 展开更多
关键词 Crohn Disease Digestive System ENDOSCOPY Gastrointestinal Diseases Humans TELEMETRY video recording
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Recording the direct surgeon’s view with an operating microscopic view improves microscopic ophthalmic surgery training
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作者 Masayuki Akimoto Kosei Tomita +1 位作者 Miyo Yoshida Yuki Hama 《International Journal of Ophthalmology(English edition)》 SCIE CAS 2023年第9期1555-1558,共4页
AIM:To establish a recording system with a direct view of the surgeon to supplement video recording under an operating microscope,which lacks information on the movement and position of the surgeon’s hands,and to fac... AIM:To establish a recording system with a direct view of the surgeon to supplement video recording under an operating microscope,which lacks information on the movement and position of the surgeon’s hands,and to facilitate the reproduction of a skilled surgeon’s technique by a surgeon in training.METHODS:A small camera was attached to the operating microscope with a custom adapter.Microscopic surgeon’s view and direct surgeon’s view through this new camera were recorded in the surgical recording system.Both movies were synchronized and analyzed how do surgeons handle the instruments.RESULTS:A small camera attached to the operating microscope allowed the surgeon’s hands motion to be recorded without interfering with the surgeon’s movements.Different surgeons used different methods to manipulate the ultrasound handpiece and the irrigation/aspiration device.Even in the simple paracentesis procedure,different surgeons used different methods.Surgeons-in-training were able to identify and improve their weaknesses by watching synchronized movies of their hand motions and microscopic view.CONCLUSION:Simultaneous recording the surgical field out of the operating microscopic view by a small camera set on the microscope is comprehensive and improves surgeons-in-training understanding and learning surgeries. 展开更多
关键词 operating microscopic view direct surgeon’s view video recording microscopic surgery training
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PBL结合病例视频录制教学方法在普通外科住院医师规范化培训中的应用效果
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作者 赵云波 王新 +2 位作者 王毅 岳彩芳 任翊华 《浙江医学教育》 2025年第4期229-233,239,共6页
目的探讨基于问题学习(problem-based learning,PBL)结合病例视频录制教学方法在普通外科住院医师规范化培训(简称住培)中的应用效果。方法选取2022年9月—2023年9月在佳木斯大学附属第一医院普通外科进行住院医师规范化培训的80名学员... 目的探讨基于问题学习(problem-based learning,PBL)结合病例视频录制教学方法在普通外科住院医师规范化培训(简称住培)中的应用效果。方法选取2022年9月—2023年9月在佳木斯大学附属第一医院普通外科进行住院医师规范化培训的80名学员为研究对象,采用随机数字表法将其分为试验组和对照组,每组均为40名学员。试验组40名学员再分为5个小组,每个小组8名学员,采用PBL结合病例视频录制教学方法;对照组40名学员采用传统讲授式教学方法。住培教学结束后,采用理论知识、基本技能考核和教学满意度问卷调查方法进行教学效果评价。结果试验组学员理论知识和基本技能考核成绩均明显高于对照组学员,其差异均具有统计学意义(均P<0.001);教学满意度问卷调查结果显示,试验组学员在提高学习兴趣,激发自主学习能力,提高文献查阅能力,增强知识理解和掌握能力,提高发现、分析和解决临床问题能力,提高临床思维能力,提高医患沟通能力,激发关爱病人的医学人文素养等方面的评价结果均优于对照组学员,其差异均具有统计学意义(均P<0.01)。结论PBL结合病例视频录制教学方法应用于普通外科住培教学中,能够有效提高学员的理论知识水平、各项临床核心胜任力和综合素养,教学效果显著,可以适度推广应用。 展开更多
关键词 基于问题学习 视频录制 住院医师规范化培训 教学方法 效果评价
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利用监控录像估算宏观烈度和强地面运动参数——以2025年西藏定日M6.8地震为例
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作者 郑怡 杨小林 马海超 《震灾防御技术》 北大核心 2025年第1期24-31,共8页
2025年1月7日西藏定日县发生了M6.8破坏性地震,震区中的一些监控录像清晰地拍摄到了震害及地震动过程。为了挖掘这些视频所记录的宏观烈度和强地面运动参数等信息,本研究尝试采用数字视频和音频分析等方法,对其中7个监控录像进行了诊断... 2025年1月7日西藏定日县发生了M6.8破坏性地震,震区中的一些监控录像清晰地拍摄到了震害及地震动过程。为了挖掘这些视频所记录的宏观烈度和强地面运动参数等信息,本研究尝试采用数字视频和音频分析等方法,对其中7个监控录像进行了诊断。结果表明:(1)6个超市所在地的宏观烈度值约为Ⅴ~Ⅶ度;(2)某民用住宅处的强地面运动持续时间约为20~25 s,并在第7 s时达到峰值;(3)利用建筑金属构件和器皿的响动声,可以间接表征当地强地面运动的主过程。该研究不仅能补充定日地震的宏观烈度和强震动记录,而且能为数智时代下的宏观烈度调查和强震动视觉测量等提供参考。 展开更多
关键词 定日M6.8地震 监控录像 音频记录 宏观烈度 强地面运动参数
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竞争交配条件下公鹅繁殖行为与亲权效率关系
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作者 张佳玥 任晓芳 +2 位作者 郝泓润 宋金婷 刘胜军 《家畜生态学报》 北大核心 2025年第8期61-65,共5页
试验旨在研究公鹅在竞争交配条件下的繁殖行为(攻击、求偶、爬跨和交尾行为)对其亲权效率(PE)的影响。选择同批次12月龄、体重相近的72只籽鹅(公鹅12只,母鹅60只)。试验包括4个平行试验组,每组随机分配3只公鹅15只母鹅(公母比例1∶5)。... 试验旨在研究公鹅在竞争交配条件下的繁殖行为(攻击、求偶、爬跨和交尾行为)对其亲权效率(PE)的影响。选择同批次12月龄、体重相近的72只籽鹅(公鹅12只,母鹅60只)。试验包括4个平行试验组,每组随机分配3只公鹅15只母鹅(公母比例1∶5)。在公鹅背部用不同颜色加以标记,在试验鹅舍四周架设录像设备,利用视频记录系统记录公鹅攻击行为、求偶行为、爬跨行为和交配行为,共计15 d。根据四种繁殖行为记录确定每天各个繁殖行为的频率。然后每组种鹅各孵化100枚种蛋,入孵16 d后提取后代DNA,利用亲子鉴定技术确定每只公鹅后代的数量,并计算公鹅个体的PE,分析公鹅个体繁殖行为对其亲权效率的影响。结果表明:公鹅的攻击行为频率和交尾行为频率对PE有较大影响。攻击频率(斗性)与交尾频率、PE存在很强的正相关。选择斗性强的公鹅可以提高竞争交配条件下公鹅的PE。 展开更多
关键词 籽鹅 繁殖行为 视频记录系统 亲权效率
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一种视频记录回放和图像复显系统设计
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作者 刘静 王飞 《广东造船》 2025年第2期44-46,43,共4页
提出一种基于硬件采集方式视频记录回放系统总体设计方案,详述了设计方案、硬件和软件构架,以简单、可靠的电路,实现显示终端显示画面信号的全部记录、存储和回放,并对于远距离屏幕复显提供了一种电路简单可靠、可借鉴的设计方法。
关键词 视频 记录 回放
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论体育赛事画面的著作权法保护
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作者 林鸿 熊清莲 《体育科学研究》 2025年第6期61-68,共8页
现行法律体系对体育赛事画面保护存在缺位,导致相关法律争议频发。为此,研究采用类型化分析方法,以独创性判定为逻辑起点,将体育赛事画面区分为实时直播、延时转播与赛后录播三种类型,系统探究其在著作权法中的差异化保护路径,并据此构... 现行法律体系对体育赛事画面保护存在缺位,导致相关法律争议频发。为此,研究采用类型化分析方法,以独创性判定为逻辑起点,将体育赛事画面区分为实时直播、延时转播与赛后录播三种类型,系统探究其在著作权法中的差异化保护路径,并据此构建法律适用框架。结果表明:具有独创性的实时直播、延时转播与赛后录播画面应作为视听作品受著作权保护;缺乏独创性的直播画面仅能作为录像制品受邻接权保护,但现行邻接权制度无法有效规制实时盗播行为。为弥补此漏洞,建议未来立法将广播权纳入录像制品的权利范畴,以完善体育赛事画面的法律保护体系。 展开更多
关键词 体育赛事画面 录像制品 广播权 著作权保护
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重复性供述排除规则的理论反思与优化
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作者 周好峰 《山西省政法管理干部学院学报》 2025年第3期68-72,共5页
重复性供述排除规则在非法证据排除领域发挥着不可替代的作用。但是不可回避的问题是,由于该规则设定的非法诱因较为单一,加之两个例外不排除的宽泛适用、重复性供述的排除缺乏有效的过滤机制、侦查机关排除重复性供述动力不足等原因使... 重复性供述排除规则在非法证据排除领域发挥着不可替代的作用。但是不可回避的问题是,由于该规则设定的非法诱因较为单一,加之两个例外不排除的宽泛适用、重复性供述的排除缺乏有效的过滤机制、侦查机关排除重复性供述动力不足等原因使得司法实践中重复性供述排除的效果并不理想。为提高该规则的规制功效,建议拓宽重复性供述排除的诱因范围,将以刑讯逼供之外的非法方法取得的重复性供述也纳入排除的考量空间,当取证主体采取其他非法方法取证与采取刑讯逼供方法取证,给被追诉人造成的痛苦程度相当时,亦应排除。重复性供述的有效排除还依赖公检法三机关的过滤与审查,为从源头上尽量阻断痛苦程度相当的重复性供述流入后续诉讼流程,立法还需发力,一方面完善侦查机关排除重复供述的奖惩措施,另一方面完善侦查讯问的同步录音录像制度,以此促使侦查机关规范取证。 展开更多
关键词 重复性供述 排除规则 刑讯逼供 录音录像 非法证据排除
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数字技术对摄像录制画质的提升作用
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作者 史寒松 《信息与电脑》 2025年第6期147-149,共3页
随着数字技术的迅猛发展,摄像录制的画质得到了显著提升,文章对此进行了研究。从传统模拟影像到如今的数字影像技术,分辨率、动态范围、色彩深度、图像处理和帧率等方面的技术进步,大大改善了画面质量。尤其是4K和8K视频技术的应用,使... 随着数字技术的迅猛发展,摄像录制的画质得到了显著提升,文章对此进行了研究。从传统模拟影像到如今的数字影像技术,分辨率、动态范围、色彩深度、图像处理和帧率等方面的技术进步,大大改善了画面质量。尤其是4K和8K视频技术的应用,使得影像的细节呈现更为精细。人工智能(Artificial Intelligence,AI)和深度学习等智能技术的引入,进一步提升了摄像设备的自动化处理能力。现代数码相机、智能手机和便携式摄像设备,都通过数字技术的加持,使得影像创作变得更加便捷和高效。 展开更多
关键词 数字技术 摄像录制 画质提升
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电梯检验无线音像记录系统的实时视频采集方法
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作者 刘泽斌 《现代制造技术与装备》 2025年第9期136-139,共4页
电梯检验无线音像记录系统的实时视频采集方法是融合多点位高清视频获取、低时延无线传输、智能化数据处理与安全存储的技术体系。分析电梯检验无线音像记录现状,研究实时视频采集需求,提出实时视频采集在采集模块、传输模块、数据处理... 电梯检验无线音像记录系统的实时视频采集方法是融合多点位高清视频获取、低时延无线传输、智能化数据处理与安全存储的技术体系。分析电梯检验无线音像记录现状,研究实时视频采集需求,提出实时视频采集在采集模块、传输模块、数据处理模块与存储模块的整体实现方法,旨在构建复杂井道环境的多点位同步、低延迟和高稳定性的检验影像采集体系。 展开更多
关键词 电梯检验 音像记录系统 实时视频采集
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钻芯检测信息化管理系统的开发与应用
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作者 王小威 《工程质量》 2025年第9期48-52,74,共6页
论文系统介绍了钻芯检测信息化管理系统的开发构思,详细从系统架构、角色权限设计、云平台设计以及移动端设计等方面阐述系统设计的思想。系统利用视频监控技术、网络通讯技术、二维码技术、移动客户端等现代化技术实现钻芯检测的现场... 论文系统介绍了钻芯检测信息化管理系统的开发构思,详细从系统架构、角色权限设计、云平台设计以及移动端设计等方面阐述系统设计的思想。系统利用视频监控技术、网络通讯技术、二维码技术、移动客户端等现代化技术实现钻芯检测的现场编录、检测数据及监控视频数据的实时传输、混凝土芯样的盲样管理以及检测快报和检测报告的自动化出具等功能,减轻了钻芯外业工作和钻芯内业工作的劳动强度,提高检测报告出具的时效性和可靠性。 展开更多
关键词 钻芯检测 视频监控 云平台 现场编录 二维码 报告自动生成
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浅地层剖面测量和海底摄像联合应用确定平顶海山富钴结壳分布界线 被引量:39
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作者 何高文 梁东红 +3 位作者 宋成兵 吴水根 周建平 张学华 《地球科学(中国地质大学学报)》 EI CAS CSCD 北大核心 2005年第4期509-512,共4页
平顶海山富钴结壳分布上界的确定对准确估算结壳资源量至关重要.长期以来,这一问题未能有效解决.通过浅地层剖面测量和海底摄像的首次联合应用,发现浅地层剖面测量揭示的海山浅部地层结构与海山结壳的分布具有明显的相关性,沉积物分布... 平顶海山富钴结壳分布上界的确定对准确估算结壳资源量至关重要.长期以来,这一问题未能有效解决.通过浅地层剖面测量和海底摄像的首次联合应用,发现浅地层剖面测量揭示的海山浅部地层结构与海山结壳的分布具有明显的相关性,沉积物分布的上界往往与结壳分布下界对应.通过对浅剖测量结果的分析,并对比海底摄像资料,可以确定沉积物分布的下界,进而推断结壳分布的上界,据此判断西太平洋某海山结壳分布的上界水深为1560m左右. 展开更多
关键词 浅地层剖面 海底摄像 平顶海山 富钴结壳 分布界线
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摄像反馈教学法在田径技术课上的应用 被引量:15
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作者 李双成 罗跃兵 +2 位作者 连佑群 王志强 洪元舟 《武汉体育学院学报》 CSSCI 北大核心 2001年第2期63-64,共2页
改革、创新教学方式、方法是每个教育工作者应努力研究、探索的课题。先拍摄学生练习时的技术动作 ,再通过电视录像当场放给练习者看 ,由他们自己判断自己的动作是否符合动作规范 ,从对比中发现错误动作或多余动作 ,在下一轮练习中加以... 改革、创新教学方式、方法是每个教育工作者应努力研究、探索的课题。先拍摄学生练习时的技术动作 ,再通过电视录像当场放给练习者看 ,由他们自己判断自己的动作是否符合动作规范 ,从对比中发现错误动作或多余动作 ,在下一轮练习中加以纠正 ,从而提高教学质量 ,缩短教学时数 ,使技术动作更规范化。 展开更多
关键词 田径 摄像 反馈 时空感 运动技术
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顶板浅部裂隙通道演化规律与分布特征 被引量:30
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作者 刘洪涛 马念杰 +2 位作者 李季 张卫伟 张世平 《煤炭学报》 EI CAS CSCD 北大核心 2012年第9期1451-1455,共5页
为得出顶板裂隙通道的演化过程和空间分布特征,以岩体力学和煤岩全应力-应变过程中瓦斯流动变化规律为理论基础,采用深部位移自动监测仪和裂隙通道巡回摄录仪,进行理论分析和现场测试研究,得出了瓦斯裂隙通道形成判据和分布特征。结果表... 为得出顶板裂隙通道的演化过程和空间分布特征,以岩体力学和煤岩全应力-应变过程中瓦斯流动变化规律为理论基础,采用深部位移自动监测仪和裂隙通道巡回摄录仪,进行理论分析和现场测试研究,得出了瓦斯裂隙通道形成判据和分布特征。结果表明:煤岩分层成为瓦斯裂隙通道边界需要满足其变形小于下分层或大于上分层,同时其稳定跨距大于顶板悬露距离,据此判别出试验矿区顶板浅部主干裂隙通道位于顶板上方1.5,5.0 m处;随工作面推进,顶板裂隙通道经历原生裂隙通道主导阶段、裂隙通道产生、扩张、成熟和闭合阶段的演化过程,重新压实区至工作面前方原岩应力区距离与工作面日推进速度的比值为裂隙通道的演化周期,试验矿区演化周期为11~14 d。 展开更多
关键词 裂隙通道 演化规律 分布特征 自动监测仪 巡回摄录仪 变形判据
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基于田间摄像的多参数水稻土深松扰动行为与效应研究 被引量:14
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作者 丁启朔 李杨 +3 位作者 BELAL Eisa Adam 梁磊 何瑞银 汪小旵 《农业机械学报》 EI CAS CSCD 北大核心 2019年第10期44-55,共12页
耕作机具的土壤扰动行为密切联系土壤失效机理与耕作效应,是优化耕作系统的重要依据。本研究通过土壤耕作原位综合测试平台开展单铲深松试验,从5个方位录制深松视频,同时配合使用微地貌测试、耕作阻力测试、EDEM仿真、深松扰动剖面土壤... 耕作机具的土壤扰动行为密切联系土壤失效机理与耕作效应,是优化耕作系统的重要依据。本研究通过土壤耕作原位综合测试平台开展单铲深松试验,从5个方位录制深松视频,同时配合使用微地貌测试、耕作阻力测试、EDEM仿真、深松扰动剖面土壤紧实度测试和深松理论检验,探究深松铲入土角α和耕深D对水稻土深松扰动过程、土壤失效机理及深松效应的影响。结果表明,摄像法提取的纵向碎土距离R、扰动宽度W及抬土高度H与α和D显著相关,可用于水稻土深松扰动行为的定量表述。摄像法显示水稻土难以脆性断裂,铲两侧发生非对称性土壤剪切失效。土壤沿曲柄攀升,抬土高度H随α增大,随D减小,表明深松铲的设计参数和作业参数同时影响抬土能力。R随对应耕深范围内铲的纵向水平长度L线性增加,W随α线性增加。地表平整度S和扰动宽度W均在耕深20 cm时最大。深松土壤扰动行为的EDEM仿真从微观层面再现了摄像法记录的非对称性失效、侧向挤压失效和深松新月形失效现象,表明该离散元模型用于解析水稻土深松力学的科学性。EDEM仿真进一步显示出应力集中区沿铲尖与铲柄破土刃周期性上下移动,同时也对铲下方底层土造成挤压。深松扰动剖面土壤紧实度等值线图验证了仿真过程中铲尖下方形成的土壤压实带,并直观展示出耕深30 cm时,犁底层土壤因侧向挤压流变形成的沟槽状紧实壁面。本文结合田间原位摄像法的多参数测试研究可为深松铲和耕作系统的优化提供依据。 展开更多
关键词 水稻土 深松过程 摄像法 耕后效应
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