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Transcriptional and signaling regulation in neural crest stem cell-derived melanocyte development: do all roads lead to Mitf? 被引量:33
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作者 Ling Hou William J Pavan 《Cell Research》 SCIE CAS CSCD 2008年第12期1163-1176,共14页
Human neurocristopathies include a number of syndromes, tumors, and dysmorphologies of neural crest (NC) stem cell derivatives. In recent years, many white spotting genes have been associated with hypopigmentary dis... Human neurocristopathies include a number of syndromes, tumors, and dysmorphologies of neural crest (NC) stem cell derivatives. In recent years, many white spotting genes have been associated with hypopigmentary disorders and deafness in neurocristopathies resulting from NC stem cell-derived melanocyte deficiency during development. These include PAX3, SOX10, MITF, SNAI2, EDNRB, EDN3, KIT, and KITL. Recent studies have revealed surprising new insights into a central role of MITF in the complex network of interacting genes in melanocyte development. In this perspective, we provide an overview of some of the current findings and explore complex functional roles of these genes during NC stem cell-derived melanocyte development. 展开更多
关键词 neurocristopathy Waardenburg syndrome white spotting mice pigment cells differentiation
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传真天气图的计算机接收识别技术 被引量:5
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作者 孟祥武 李文芳 +1 位作者 孙吉清 廖木星 《中国航海》 CSCD 北大核心 2000年第1期16-21,共6页
本文研究讨论了利用计算机接收识别传真天气图的理论和方法 ,包括 :传真天气图的计算机接收、信号转换、图像的二值化、细化、矢量化以及等压线的识别与提取的理论和方法。该技术在实际应用中 。
关键词 传真天气图 二值化 矢量化 计算机 接收识别技术
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数字微阵列点样喷头试验研究 被引量:5
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作者 房汝建 侯丽雅 章维一 《中国机械工程》 EI CAS CSCD 北大核心 2005年第1期46-50,共5页
利用压电陶瓷驱动器产生的低频微振动,实现了连续微流体的均匀离散和喷射。在试验所用的低频范围内(1~10Hz),点样系统能够对每个驱动脉冲作出响应,具有数字可控性。通过疏水化处理技术消除微喷嘴的“流挂”现象,实现了微喷射量可控。... 利用压电陶瓷驱动器产生的低频微振动,实现了连续微流体的均匀离散和喷射。在试验所用的低频范围内(1~10Hz),点样系统能够对每个驱动脉冲作出响应,具有数字可控性。通过疏水化处理技术消除微喷嘴的“流挂”现象,实现了微喷射量可控。微振动可以有效地消除微小颗粒可能对微喷嘴造成的堵塞,提高了点样喷头工作的可靠性。驱动频率对液滴直径有显著的影响。可以通过改变频率高低和微喷嘴内径大小实现皮升(pL)级点样喷射。 展开更多
关键词 点样 微阵列 微喷嘴 离散化 微喷射
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TextFormer: A Query-based End-to-end Text Spotter with Mixed Supervision
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作者 Yukun Zhai Xiaoqiang Zhang +3 位作者 Xiameng Qin Sanyuan Zhao Xingping Dong Jianbing Shen 《Machine Intelligence Research》 EI CSCD 2024年第4期704-717,共14页
End-to-end text spotting is a vital computer vision task that aims to integrate scene text detection and recognition into a unified framework.Typical methods heavily rely on region-of-interest(Rol)operations to extrac... End-to-end text spotting is a vital computer vision task that aims to integrate scene text detection and recognition into a unified framework.Typical methods heavily rely on region-of-interest(Rol)operations to extract local features and complex post-processing steps to produce final predictions.To address these limitations,we propose TextFormer,a query-based end-to-end text spotter with a transformer architecture.Specifically,using query embedding per text instance,TextFormer builds upon an image encoder and a text decoder to learn a joint semantic understanding for multitask modeling.It allows for mutual training and optimization of classification,segmentation and recognition branches,resulting in deeper feature sharing without sacrificing flexibility or simplicity.Additionally,we design an adaptive global aggregation(AGG)module to transfer global features into sequential features for reading arbitrarilyshaped texts,which overcomes the suboptimization problem of Rol operations.Furthermore,potential corpus information is utilized from weak annotations to full labels through mixed supervision,further improving text detection and end-to-end text spotting results.Extensive experiments on various bilingual(i.e.,English and Chinese)benchmarks demonstrate the superiority of our method.Especially on the TDA-ReCTS dataset,TextFormer surpasses the state-of-the-art method in terms of 1-NED by 13.2%. 展开更多
关键词 End-to-end text spotting arbitrarily-shaped texts transformer mixed supervision multitask modeling.
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关键词识别的基本技术和研究进展 被引量:2
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作者 陈凯江 欧嘉致 +1 位作者 黄萱菁 吴立德 《计算机科学》 CSCD 北大核心 2002年第2期115-119,97,共6页
Keyword Spotting (KWS) or Keyword Recognition is to recognize a set of given keywords in continuous,spontaneous speech.It is a very active branch of Speech Recognition.It differs from Continuous Speech Recognition (CS... Keyword Spotting (KWS) or Keyword Recognition is to recognize a set of given keywords in continuous,spontaneous speech.It is a very active branch of Speech Recognition.It differs from Continuous Speech Recognition (CSR) in terms of research focus,implementation techniques and application background.So they are often regarded as two different issues.This paper gives an overview of basic techniques and advances in recent years,including how to combine the traits of Mandarin. 展开更多
关键词 语音识别 关键词识别 信息处理 多媒体 计算机
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HarkMan──A Vocabulary-Independent Keyword Spotter for Spontaneous Chinese Speech
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作者 郑方 徐明星 +3 位作者 牟晓隆 武健 吴文虎 方棣棠 《Journal of Computer Science & Technology》 SCIE EI CSCD 1999年第1期18-26,共9页
in this paper a novel technique adopted in HarkMan is introduced. HarkMan is a keyword-spotter designed to automatically spot the given words of a vocabulary-independent task in unconstrained Chinese telephone speech.... in this paper a novel technique adopted in HarkMan is introduced. HarkMan is a keyword-spotter designed to automatically spot the given words of a vocabulary-independent task in unconstrained Chinese telephone speech. The speak- ing manner and the number of keywords are not limited. This paper focuses on the novel technique which addresses acoustic modeling, keyword spotting network, search strategies, robustness, and rejection. The underlying technologies used in HarkMan given in this paper are useful not only for keyword spotting but also for continuous speech recognition. The system has achieved a figure-of-merit value over 90%. 展开更多
关键词 keyword spotting keyword spotter vocabulary independent acoustic modeling continuous speech recognition
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Characterization of a novel missense mutation on murine Pax3 through ENU mutagenesis 被引量:2
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作者 Yue Xiao Lingling Zhang +5 位作者 Kuanjun He Xiang Gao Lun Yang Lin He Gang Ma Xizhi Guo 《Journal of Genetics and Genomics》 SCIE CAS CSCD 2011年第8期333-339,共7页
N-ethyl-N-nitrosourea (ENU) mutagenesis has led to the elucidation of several regulator genes for melanocyte and skin development. Here we characterized a mutant from ENU mutagenesis with similar phenotype as that o... N-ethyl-N-nitrosourea (ENU) mutagenesis has led to the elucidation of several regulator genes for melanocyte and skin development. Here we characterized a mutant from ENU mutagenesis with similar phenotype as that of Splotch mutant, including exencephaly, spina bifida and abnormal limbs in homozygotes as well as white belly spotting and occasionally loop-tail in heterozygotes. This novel mutant was named as SpxG. Through genome-wide linkage analysis in backcross progenies with microsatellite markers, the SpxG was confined to a region between DIMIT415 and DIMIT7 on chromosome 1, where notable Pax3 gene was located. Direct sequencing revealed that SpxG carried a nucleotide A894G missense transition in exon 6 of Pax3 gene that resulted in Asn to Asp substitution at amino acid 269 within the highly-conserved homeodomain (HD) DNA recognition module, which was the first point mutation found in this domain in mice. This N269D mutation impaired the transactivation capacity of Pax3 protein, but exerted no effect on Pax3 protein translation. The characterization of the new mutation expanded our understanding the transactivation and DNA-binding structure of Pax3 protein. 展开更多
关键词 White spotting Neural tube defect ENU PAX3 TRANSACTIVATION
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有棱丝瓜点状斑纹性状主基因+多基因遗传分析
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作者 朱德宁 吴宇军 +1 位作者 曹翠文 李莲芳 《江西农业学报》 CAS 2023年第6期54-61,共8页
以2个有点、1个无点类型有棱丝瓜为材料,分别构建了2个六世代遗传群体(群体RL、群体LD),应用植物数量性状主基因+多基因混合遗传模型对有棱丝瓜点状斑纹性状进行了遗传分析。有棱丝瓜点状斑纹性状最佳模型是E1(MX2-ADI-ADI)模型,即符合... 以2个有点、1个无点类型有棱丝瓜为材料,分别构建了2个六世代遗传群体(群体RL、群体LD),应用植物数量性状主基因+多基因混合遗传模型对有棱丝瓜点状斑纹性状进行了遗传分析。有棱丝瓜点状斑纹性状最佳模型是E1(MX2-ADI-ADI)模型,即符合主基因加性-显性-上位性+多基因加性-显性-上位性遗传效应。遗传分析显示,F2群体的主基因遗传率较高,为99.3%,多基因遗传率为0,表明有棱丝瓜点状斑纹性状以主基因控制为主。另外,第1、第2对主基因的加性效应值分别为-0.75、-0.75,显性效应值分别0.24、0.75。加性-加性互作效应值为1.75,显性-显性互作效应值为0.27,加性-显性互作效应值为-0.75,显性-加性互作效应值为0.76,表明第1主基因以加性效应为主,显性效应为辅,且加性为负向效应;第2主基因加性效应与显性效应相当,且分别为负向效应、正向效应。有棱丝瓜点状斑纹性状受环境的影响相对较小,点状斑纹性状的基因型与环境互作效应不大。因此,点状斑纹可作为创新大肉类型有棱丝瓜外观品质性状早期选择的指标。 展开更多
关键词 有棱丝瓜 点状斑纹 数量性状 主基因+多基因 遗传分析
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基于深度可分离卷积神经网络的关键词识别系统 被引量:4
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作者 王帅 彭意兵 何顶新 《微电子学与计算机》 北大核心 2019年第9期103-108,共6页
关键词识别系统是智能语音交互系统的重要组成部分.本文使用Google语音命令数据集,探索使用传统卷积神经网络和深度可分离卷积神经网络在关键词识别任务中的应用,对两种卷积神经网络模型从识别率、计算量、内存消耗进行对比,并提出适用... 关键词识别系统是智能语音交互系统的重要组成部分.本文使用Google语音命令数据集,探索使用传统卷积神经网络和深度可分离卷积神经网络在关键词识别任务中的应用,对两种卷积神经网络模型从识别率、计算量、内存消耗进行对比,并提出适用于受限设备的低资源、较高识别率的网络模型.实验结果显示无论传统卷积神经网络还是深度可分离卷积神经网络在关键词识别任务中的表现都优于传统的的隐马尔科夫模型和全连接深度学习模型,而深度可分离卷积神经网络进一步优于传统卷积神经网络. 展开更多
关键词 关键词识别 卷积神经网络 深度可分离卷积神经网络 受限设备
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Chinese Calligraphy Word Spotting Using Elastic HOG Feature and Derivative Dynamic Time Warping 被引量:1
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作者 Yong Xia Zhi-Bo Yang Kuan-Quan Wang 《Journal of Harbin Institute of Technology(New Series)》 EI CAS 2014年第2期21-27,共7页
Chinese calligraphy is a very special style of handwriting and direct character recognition is very difficult. Content-based keyword spotting is more feasible than recognition-based retrieval for calligraphy document.... Chinese calligraphy is a very special style of handwriting and direct character recognition is very difficult. Content-based keyword spotting is more feasible than recognition-based retrieval for calligraphy document. In this paper,we propose a novel Elastic Histogram of Oriented Gradient( EHOG) descriptor for calligraphy word spotting. The presented feature is a modification of Histogram of Oriented Gradient( HOG), widely used in human detection. In our approach,the input word image is partitioned into non-uniform rectangular cells according to the calligraphy character pixel intensity,and then in each cell a histogram of orientation is accumulated dynamically. Moreover,we adopt Derivative Dynamic Time Warping( DDTW) for image feature matching,which achieves good performance in gesture recognition. Experiments demonstrate a very significant improvement when comparing our proposed feature with previously developed ones,and also show DDTW produces superior alignments between two calligraphy character feature series than DTW. 展开更多
关键词 calligraphy word spotting Elastic HOG DDTW
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新型非接触式微液滴点样喷头的研制 被引量:3
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作者 赵启焱 尤晖 +1 位作者 郑敏捷 黄哲 《仪表技术》 2017年第9期26-29,共4页
微阵列芯片在基因检测等领域有着广泛的应用,制备微阵列芯片的的点样设备可分为接触式和非接触式两种,其中接触式点样需要频繁的清洗点样针头,非接触式点样设备则需要外界气泵或使用复杂的MEMS工艺制作。为了简化生物微阵列芯片制作过... 微阵列芯片在基因检测等领域有着广泛的应用,制备微阵列芯片的的点样设备可分为接触式和非接触式两种,其中接触式点样需要频繁的清洗点样针头,非接触式点样设备则需要外界气泵或使用复杂的MEMS工艺制作。为了简化生物微阵列芯片制作过程中繁琐的取样、点样、清洗工作和降低点样仪器的成本,研制了一种新型的储液式微液滴点样装置,具有无需清洗、成本低、制作简便的优点。该装置采用压电陶瓷双晶片作为动力驱动,通过双晶片在液体中的振动激发出水击波,传递至喷孔处使喷孔液面发生振动,从而激发出微液滴滴落。研制的储液式微液滴点样装置可以容纳1 mL的液体试剂,可得到体积为1 nL的微液滴,可重复上万次的点样而不需清洗。以储液式微液滴点样装置为基础,进一步制作了点样仪样机。根据实验测量,储液式微液滴点样装置所产生微液滴的直径为200μm,可以满足生物微阵列芯片的制备要求。 展开更多
关键词 微液滴 点样 压电陶瓷 生物芯片
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提升冲压模具型面研配质量及效率的方案分析 被引量:3
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作者 黄罴 唐雅 宾小林 《装备制造技术》 2017年第12期136-139,共4页
通过调查分析冲压模具在研配过程中所存在的问题,找出影响模具研配效率及质量的关键点,再针对这些关键点进行深入讨论分析,制定问题解决方案,通过实践验证解决方案的可行性,减少研配工作时间,提升模具制造质量及效率。
关键词 冲压模具 研配 红丹贴合率
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Diameter Measurements of the Upper Parts of Trees Using an Ultra-Telephoto Digital Photography System
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作者 Akira Shimizu Shigeki Yamada Yuichiro Arita 《Open Journal of Forestry》 2014年第4期316-326,共11页
We develop a new technique to measure the exact upper diameters of trees that is comparatively simple and inexpensive. We can measure the diameters of entire tree trunks efficiently and with high precision. The system... We develop a new technique to measure the exact upper diameters of trees that is comparatively simple and inexpensive. We can measure the diameters of entire tree trunks efficiently and with high precision. The system uses a digital camera with a ~15 - 30× telephoto lens to take a photograph that can be used for measuring the diameter of the upper part of a comparatively slender tree trunk. Since this method requires a measuring distance and the height of the target point in the image, a range finder capable of measuring angles was combined with the main digiscoping system. A range finder sensor uses a laser and makes a 360 degree angle of observation possible. The diameter of a target position of the objective tree can be obtained by measuring the digital image using image editing software and calculations from spreadsheet software. We focus on the Japanese cedar species in the southwestern part of Japan. Photographic measurements were obtained prior to thinning. The estimates that we obtained largely agree with the true measurements of all trees. With regard to the estimated accuracy of all measured trees, the maximum error ratio was 7.0% (1.45 cm), with a ~2% - 4% error for most of the estimated results. Although the absolute value of the estimation error was 1.87 cm (5.3%) at the maximum (9.87 m in height and 35.5 cm in diameter), an estimation accuracy of <1 cm was reproduced in almost all measurements except for the extreme hypertrophy portion by butt swelling. 展开更多
关键词 Digital Camera Image EDITING Software Magnifications spotting SCOPE TAPER Curve UPPER Diameter
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Semantic Model for Voice Controlled Telephone Dialing and Inquiry Systems
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作者 张建平 王作英 《Tsinghua Science and Technology》 EI CAS 2000年第2期217-221,共5页
A new scheme is presented to detect a large number ofKeywordsin voice controlled switchboard tasks. The new scheme is based on two stages. In the first stage, N best syllable candidates with their corresponding acous... A new scheme is presented to detect a large number ofKeywordsin voice controlled switchboard tasks. The new scheme is based on two stages. In the first stage, N best syllable candidates with their corresponding acoustic scores are generated by an acoustic recognizer. In the second stage, a semantic model based parser is applied to determine the optimum keywords by searching through the lattice of N best candidates. The experimental results show that when the spoken input deviates from the predefined syntactic constraints, the parser can also demonstrate high performance. For comparison purposes, the most common way to incorporate the syntactic knowledge of the task directly into the acoustic recognizer in the form of a finite state network is also investigated. Furthermore, to address the sparse data problems, out of domain data in the form of newspaper text are used to obtain a more robust combined semantic model. The experiments show that the combined semantic model can improve the keywords detection rate from 90.07% to 92.91% when 80 ungrammatical sentences which do not conform to the task grammar are used as testing material. 展开更多
关键词 Key words semantic model language model keywords spotting context free grammar N best candidates PERPLEXITY
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Utilization of Hot Spotting to Identify Community Needs and Coordinate Care for High-Cost Patients in Memphis, TN
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作者 Teresa Cutts Edward Rafalski +1 位作者 Cori Grant Razvan Marinescu 《Journal of Geographic Information System》 2014年第1期23-29,共7页
In 2006, Methodist Le Bonheur Healthcare (MLH) created the Congregational Health Network (CHN, TM pending) which works closely with clergy in the most under-served zip codes of the city to improve access to care and o... In 2006, Methodist Le Bonheur Healthcare (MLH) created the Congregational Health Network (CHN, TM pending) which works closely with clergy in the most under-served zip codes of the city to improve access to care and overall health status of the population. To best coordinate CHN resources around high-utilization and address the largest health needs in the community, MLH applied hot spotting and geographic information system (GIS) spatial analysis techniques. These techniques were coupled with the community health needs assessment process at MLH and qualitative, participatory research findings captured in collaboration with church and other community partners. The methodology, which we call “participatory hot spotting,” is based upon the Camden Model, which leverages hot spotting to assess and prioritize community need in the provision of charity care, but adds a participatory, qualitative layer. In this study, spatial analysis was employed to evaluate hospital-based inpatient and outpatient utilization and define costs of charity care for the health system by area of residence. Ten zip codes accounted for 56% of total system charity care costs. Among these, the largest zip code, as defined by a percentage of total charity costs, contributed 18% of the inpatient utilization and 17% of the cost. Further, this zip code (38109) contributed 69% of the inpatient and 76% of the outpatient charity care volume and accounted for 75% of inpatient and 76% of outpatient charity care costs for the system. These findings were combined with grassroots intelligence that enabled a partnership with clergy and community members and Cigna Healthcare to better coordinate care in a place-based population health management strategy. Presentations of the analytics have subsequently been made to HHS and the CDC, referred to by some as the “Memphis Model”. 展开更多
关键词 Hot spotting CHNA (Community HEALTH Needs Assessment) Congregational HEALTH Network (CHN) MEMPHIS Model HEALTH DISPARITIES
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BISIO蒸呢机蒸呢工艺研究及开发应用 被引量:2
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作者 杜元姝 王科林 +1 位作者 孟霞 张庆娟 《毛纺科技》 CAS 北大核心 2014年第10期32-35,共4页
文章分析讨论了蒸呢温度、蒸呢工作压力、蒸呢时间、包布张力、压辊压力和通汽方式对BISIO蒸呢机产品质量的影响程度。结果表明:蒸呢时间、包布张力、压辊压力和上机匹数对产品质量和风格影响显著,实际生产时应根据产品质量和风格合理... 文章分析讨论了蒸呢温度、蒸呢工作压力、蒸呢时间、包布张力、压辊压力和通汽方式对BISIO蒸呢机产品质量的影响程度。结果表明:蒸呢时间、包布张力、压辊压力和上机匹数对产品质量和风格影响显著,实际生产时应根据产品质量和风格合理选择蒸呢工作参数。通过研究BISIO蒸呢机蒸呢工艺,解决了高温高压蒸呢工艺产品手感板硬、内外层色差及边中色差较大等问题,开发出了一套适合不同光泽和风格的精纺毛织物蒸呢工艺参数。 展开更多
关键词 蒸呢机 蒸呢工艺 色差 毛织物
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Review of micro-expression spotting and recognition in video sequences 被引量:2
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作者 Hang PAN Lun XIE +3 位作者 Zhiliang WANG Bin LIU Minghao YANG Jianhua TAO 《Virtual Reality & Intelligent Hardware》 2021年第1期1-17,共17页
Facial micro-expressions are short and imperceptible expressions that involuntarily reveal the true emotions that a person may be attempting to suppress,hide,disguise,or conceal.Such expressions can reflect a person&#... Facial micro-expressions are short and imperceptible expressions that involuntarily reveal the true emotions that a person may be attempting to suppress,hide,disguise,or conceal.Such expressions can reflect a person's real emotions and have a wide range of application in public safety and clinical diagnosis.The analysis of facial micro-expressions in video sequences through computer vision is still relatively recent.In this research,a comprehensive review on the topic of spotting and recognition used in micro expression analysis databases and methods,is conducted,and advanced technologies in this area are summarized.In addition,we discuss challenges that remain unresolved alongside future work to be completed in the field of micro-expression analysis. 展开更多
关键词 Facial expression Micro-expression spotting Micro-expression recognition DATABASE REVIEW
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全站仪极坐标法测设物探网的一种新方法 被引量:1
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作者 张维宽 张永胜 孟红 《价值工程》 2012年第11期26-27,共2页
介绍了全站仪极坐标法布设、测定点位的基本原理以及工作方法,指明了传统测设物探网方法的不足,并对点位精度问题进行了探讨,提出了一种能够满足物探网精度要求,又能加快放样速度、节省人力、提高经济效益的新方法。
关键词 全站仪 极坐标法 测定点位 物探网 点位精度
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汽车覆盖件模具研合蓝油图研究 被引量:1
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作者 王健 赵子海 +2 位作者 王国峰 王礼昌 才亚东 《模具制造》 2021年第3期25-27,共3页
针对汽车覆盖件的模具研合蓝油图进行了研究,通过制定合理的模具研合蓝油图,可以有效缩短模具研合周期为原周期的2/3;对提升覆盖件零件质量、外观面品有较大提高。
关键词 蓝油图 研合率 汽车覆盖件 模具
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PCR产物溶剂的选择对杂交信号的影响
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作者 庄远红 《湖南师范大学自然科学学报》 EI CAS 北大核心 2006年第3期86-88,共3页
在基因芯片技术中,提高杂交信号有利于增加基因表达变化比值的可信度.通过研究不同溶剂来溶解PCR产物后,点样对杂交信号的影响,使基因芯片的技术环节得到优化.
关键词 基因芯片 PCR产物 点样
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