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Time-sequential color code division multiplexing holographic display with metasurface 被引量:17
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作者 Xin Li Qinmiao Chen +4 位作者 Xue Zhang Ruizhe Zhao Shumin Xiao Yongtian Wang Lingling Huang 《Opto-Electronic Advances》 SCIE EI CAS CSCD 2023年第8期8-16,共9页
Color metasurface holograms are powerful and versatile platforms for modulating the amplitude,phase,polarization,and other properties of light at multiple operating wavelengths.However,the current color metasurface ho... Color metasurface holograms are powerful and versatile platforms for modulating the amplitude,phase,polarization,and other properties of light at multiple operating wavelengths.However,the current color metasurface holography can only realize static manipulation.In this study,we propose and demonstrate a multiplexing metasurface technique combined with multiwavelength code-division multiplexing(CDM)to realize dynamic manipulation.Multicolor code references are utilized to record information within a single metasurface and increase the information capacity and security for anticracks.A total of 48 monochrome images consisting of pure color characters and multilevel color video frames were reconstructed in dual polarization channels of the birefringent metasurface to exhibit high information density,and a video was displayed via sequential illumination of the corresponding code patterns to verify the ability of dynamic manipulation.Our approach demonstrates significant application potential in optical data storage,optical encryption,multiwavelengthversatile diffractive optical elements,and stimulated emission depletion microscopy. 展开更多
关键词 metasurface color holography dynamic display code division multiplexing
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Maximum two-dimensional (u×v,4,1,3)-OOCs 被引量:2
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作者 HUANG Yue-mei CHANG Yan-xun 《Applied Mathematics(A Journal of Chinese Universities)》 SCIE CSCD 2013年第3期279-289,共11页
Let Ф(u ×v, k, Aa, Ac) be the largest possible number of codewords among all two- dimensional (u ×v, k, λa, λc) optical orthogonal codes. A 2-D (u× v, k, λa, λ)-OOC with Ф(u× v, k, λ... Let Ф(u ×v, k, Aa, Ac) be the largest possible number of codewords among all two- dimensional (u ×v, k, λa, λc) optical orthogonal codes. A 2-D (u× v, k, λa, λ)-OOC with Ф(u× v, k, λa, λc) codewords is said to be maximum. In this paper, the number of codewords of a maximum 2-D (u × v, 4, 1, 3)-OOC has been determined. 展开更多
关键词 MAXIMUM two-dimensional optical orthogonal code orbit.
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Full color ghost imaging by using both time and code division multiplexing technologies
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作者 Le Wang Hui Guo Shengmei Zhao 《Chinese Physics B》 SCIE EI CAS CSCD 2022年第11期316-323,共8页
We propose a new full color ghost imaging scheme using both time and code division multiplexing technologies.In the scheme,the speckle patterns of three colors(red,green and blue)are modulated with different time slot... We propose a new full color ghost imaging scheme using both time and code division multiplexing technologies.In the scheme,the speckle patterns of three colors(red,green and blue)are modulated with different time slots and codes.The light intensity is sampled by one bucket detector.Then based on the modulated time slots and codes,we can effectively and simultaneously extract three detection component signals corresponding to three color components of objects from the sampling signal of the bucket detector.Finally,three component images resulting from the three component detection signals can be synthesized into a full color image.The experimental results verify the feasibility of our scheme under the limit of the number of time slots and codes.Moreover,our scheme reduces the number of bucket detectors and can realize high quality imaging even in a noisy environment. 展开更多
关键词 ghost imaging time division multiplexing code division multiplexing full color imaging
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New Quantum Color Codes Based on Hyperbolic Geometry
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作者 Avaz Naghipour Duc Manh Nguyen 《Journal of Quantum Computing》 2022年第2期113-120,共8页
In this paper,hyperbolic geometry is used to constructing new quantum color codes.We use hyperbolic tessellations and hyperbolic polygons to obtain them by pairing the edges on compact surfaces.These codes have minimu... In this paper,hyperbolic geometry is used to constructing new quantum color codes.We use hyperbolic tessellations and hyperbolic polygons to obtain them by pairing the edges on compact surfaces.These codes have minimum distance of at least 4 and the encoding rate near to 1,which are not mentioned in other literature.Finally,a comparison table with quantum codes recently proposed by the authors is provided. 展开更多
关键词 color codes compact surfaces hyperbolic geometry tessellations
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A color image encryption scheme based on a 2D coupled chaotic system and diagonal scrambling algorithm
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作者 苏静明 方士辉 +1 位作者 洪炎 温言 《Chinese Physics B》 SCIE EI CAS CSCD 2024年第7期233-243,共11页
A novel color image encryption scheme is developed to enhance the security of encryption without increasing the complexity. Firstly, the plain color image is decomposed into three grayscale plain images, which are con... A novel color image encryption scheme is developed to enhance the security of encryption without increasing the complexity. Firstly, the plain color image is decomposed into three grayscale plain images, which are converted into the frequency domain coefficient matrices(FDCM) with discrete cosine transform(DCT) operation. After that, a twodimensional(2D) coupled chaotic system is developed and used to generate one group of embedded matrices and another group of encryption matrices, respectively. The embedded matrices are integrated with the FDCM to fulfill the frequency domain encryption, and then the inverse DCT processing is implemented to recover the spatial domain signal. Eventually,under the function of the encryption matrices and the proposed diagonal scrambling algorithm, the final color ciphertext is obtained. The experimental results show that the proposed method can not only ensure efficient encryption but also satisfy various sizes of image encryption. Besides, it has better performance than other similar techniques in statistical feature analysis, such as key space, key sensitivity, anti-differential attack, information entropy, noise attack, etc. 展开更多
关键词 color image encryption discrete cosine transform two-dimensional(2D)coupled chaotic system diagonal scrambling
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New Approach for 3D Shape Measurement Based on Color-Coded Fringe and Neural Network
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作者 QIN Da-hui, SHI Yu-sheng, WANG Cong-jun , LI Zhong-wei (State Key Laboratory of Material Processing and Die & Mould Technology, Huazhong University of Science and Technology, Wuhan 430074, China) 《Computer Aided Drafting,Design and Manufacturing》 2008年第2期50-56,共7页
A new 3D surface contouring and ranging system based on digital fringe projection and phase shifting technique is presented. Using the phase-shift technique, points cloud with high spatial resolution and limited accur... A new 3D surface contouring and ranging system based on digital fringe projection and phase shifting technique is presented. Using the phase-shift technique, points cloud with high spatial resolution and limited accuracy can be generated. Stereo-pair images obtained from two cameras can be used to compute 3D world coordinates of a point using traditional active triangulation approach, yet the camera calibration is crucial. Neural network is a well-known approach to approximate a nonlinear system without an explicit physical model, in this work it is used to train the stereo vision application system to calculating 3D world coordinates such that the camera calibration can be bypassed. The training set for neural network consists of a variety of stereo-pair images and the corresponding 3D world coordinates. The picture elements correspondence problem is solved by using projected color-coded fringes with different orientations. Color imbalance is completely eliminated by the new color-coded method. Once the high accuracy correspondence of 2D images with 3D points is acquired, high precision 3D points cloud can be recognized by the well trained net. The obvious advantage of this approach is that high spatial resolution can be obtained by the phase-shifting technique and high accuracy 3D object point coordinates are achieved by the well trained net which is independent of the camera model works for any type of camera. Some experiments verified the performance of the method. 展开更多
关键词 3D shape measurement color-coded fringe neural network correspondence problem color imbalance
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Color Image Segmentation Based on HSI Model 被引量:6
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作者 章毓晋 《High Technology Letters》 EI CAS 1998年第1期30-33,共4页
he objective of the research is to develop a fast procedure for segmenting typical videophone images. In this paper, a new approach to color image segmentation based on HSI(Hue, Saturation, Intensity) color model is r... he objective of the research is to develop a fast procedure for segmenting typical videophone images. In this paper, a new approach to color image segmentation based on HSI(Hue, Saturation, Intensity) color model is reported. It is in contrast to the conventional approaches by using the three components of HSI color model in succession. This strategy makes the segmentation procedure much fast and effective. Experimental results with typical “headandshoulders” real images taken from videophone sequences show that the new appproach can fulfill the application requirements. 展开更多
关键词 Modelbased CODING HSI color MODEL color transformation IMAGE SEGMENTATION
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Multiple bit upsets mitigation in memory by using improved hamming codes and parity codes 被引量:1
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作者 祝名 肖立伊 田欢 《Journal of Harbin Institute of Technology(New Series)》 EI CAS 2010年第5期726-730,共5页
This paper combines improved Hamming codes and parity codes to assure the reliability of memory in presence of multiple bit upsets with low cost overhead.The redundancy bits of improved Hamming codes will be appended ... This paper combines improved Hamming codes and parity codes to assure the reliability of memory in presence of multiple bit upsets with low cost overhead.The redundancy bits of improved Hamming codes will be appended at the end of data bits,which eliminates the overhead of interspersing the redundancy bits at the encoder and decoder.The reliability of memory is further enhanced by the layout architecture of redundancy bits and data bits.The proposed scheme has been implemented in Verilog and synthesized using the Synopsys tools.The results reveal that the proposed method has about 19% less area penalties and 13% less power consumption comparing with the current two-dimensional error codes,and its latency of encoder and decoder is 63% less than that of Hamming codes. 展开更多
关键词 MEMORY multiple bit upsets improved hamming codes two-dimensional error codes
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Color compensation for multi-view video coding based on diversity of cameras 被引量:1
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作者 Jun-yan HUO Yi-lin CHANG +1 位作者 Hai-tao YANG Shuai WAN 《Journal of Zhejiang University-Science A(Applied Physics & Engineering)》 SCIE EI CAS CSCD 2008年第12期1631-1637,共7页
A novel color compensation method for multi-view video coding (MVC) is proposed, which efficiently exploits the inter-view dependencies between views with the existence of color mismatch caused by the diversity of cam... A novel color compensation method for multi-view video coding (MVC) is proposed, which efficiently exploits the inter-view dependencies between views with the existence of color mismatch caused by the diversity of cameras. A color compensation model is developed in RGB channels and then extended to YCbCr channels for practical use. A modified inter-view reference picture is constructed based on the color compensation model, which is more similar to the coding picture than the original inter-view reference picture. Moreover, the color compensation factors can be derived in both encoder and decoder, therefore no additional data need to be transmitted to the decoder. The experimental results show that the proposed method improves the coding efficiency of MVC and maintains good subjective quality. 展开更多
关键词 Multi-view video coding (MVC) H.264/AVC color compensation Diversity of cameras
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A New Pseudo-color Transform for Fibre Masses Inspection of Industrial Images 被引量:2
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作者 LU Xiang-Ju DING Ming-Xiao WANG Yun-Kuan 《自动化学报》 EI CSCD 北大核心 2009年第3期233-238,共6页
关键词 CFS 自动化系统 模糊控制 计算机
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A reordered first fit algorithm based novel storage scheme for parallel turbo decoder
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作者 张乐 贺翔 +1 位作者 徐友云 罗汉文 《Journal of Shanghai University(English Edition)》 CAS 2007年第4期380-384,共5页
In this paper we discuss a novel storage scheme for simultaneous memory access in parallel turbo decoder. The new scheme employs vertex coloring in graph theory. Compared to a similar method that also uses unnatural o... In this paper we discuss a novel storage scheme for simultaneous memory access in parallel turbo decoder. The new scheme employs vertex coloring in graph theory. Compared to a similar method that also uses unnatural order in storage, our scheme requires 25 more memory blocks but allows a simpler configuration for variable sizes of code lengths that can be implemented on-chip. Experiment shows that for a moderate to high decoding throughput (40-100 Mbps), the hardware cost is still affordable for 3GPP's (3rd generation partnership project) interleaver. 展开更多
关键词 turbo codes parallel turbo decoding INTERLEAVER vertex coloring reordered first fit algorithm (RFFA) fieldprogrammable gate array (FPGA).
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用VISUAL FOXPRO生成CODE 39条形码位图文件
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作者 王集成 《计算机与数字工程》 2004年第5期12-16,共5页
本文应用CODE39条形码技术,解决了实际工作中输入学生的学号、准考证号以及身份证号等数字问题。将上述这些信息以CODE39条形码方式打印在学生证或准考证上,通过激光条形码阅读器准确快速读出这些信息进行处理,避免重复性输入,提高了工... 本文应用CODE39条形码技术,解决了实际工作中输入学生的学号、准考证号以及身份证号等数字问题。将上述这些信息以CODE39条形码方式打印在学生证或准考证上,通过激光条形码阅读器准确快速读出这些信息进行处理,避免重复性输入,提高了工作效率,降低了误码率发生。由于学号、准考证号以及身份证号存在数字、英文字母,所以,我在实际工作中选用CODE39条形码。 展开更多
关键词 code39 起始码 资料码 校验码 终止码 WINDOWS位图 颜色表图像数据区
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Edge Coloring of Graphs with Applications in Coding Theory
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作者 Ghaffar Raeisi Mohammad Gholami 《China Communications》 SCIE CSCD 2021年第1期181-195,共15页
In this paper,a new type of edge coloring of graphs together with an algorithm for such an edge coloring is presented to construct some columnweight three low-density parity-check(LDPC)codes whose Tanner graphs are fr... In this paper,a new type of edge coloring of graphs together with an algorithm for such an edge coloring is presented to construct some columnweight three low-density parity-check(LDPC)codes whose Tanner graphs are free of 4-cycles.This kind of edge coloring is applied on some well-known classes of graphs such as complete graphs and complete bipartite graphs to generate some column-weight 3 LDPC codes having flexibility in terms of code length and rate.Interestingly,the constructed(3;k)-regular codes with regularities k=4;5;:::;22 have lengths n=12;20;26,35;48;57;70;88;104;117;140;155;176;204;228;247;280;301;330;having minimum block length compared to the best known similar codes in the literature.In addition to linear complexity of generating such parity-check matrices,they can be considered as the base matrices of some quasi-cyclic(QC)LDPC codes with maximum achievable girth 18,which inherit the low-complexity encoder implementations of QC-LDPC codes.Simulation results show that the QC-LDPC codes with large girth lifted from the constructed base matrices have good performances and outperform random codes,progressive edge growth LDPC codes,some finite fields and group rings based QC-LDPC codes and also have a close competition to the standard IEEE 802.16e(WiMAX)code. 展开更多
关键词 low-density parity-check code edge coloring Quasi-cyclic LDPC code GIRTH AWGN channel
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CODING-ORIENTED MULTI-VIEW VIDEO COLOR CORRECTION
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作者 Shao Feng Jiang Gangyi +1 位作者 Yu Mei Chen Xiexiong 《Journal of Electronics(China)》 2008年第6期721-727,共7页
Color inconsistency between views is an important problem to be solved in multi-view video applications, such as free viewpoint television and other three-dimensional video systems. In this paper, by combining with mu... Color inconsistency between views is an important problem to be solved in multi-view video applications, such as free viewpoint television and other three-dimensional video systems. In this paper, by combining with multi-view video coding, a coding-oriented multi-view video color correction method is proposed. We first separate foreground and background in first Group Of Pictures (GOP) by using SKIP coding mode. Then by transferring means and standard deviations in backgrounds, color correction is performed for each frame in GOP, and multi-view video coding is performed and used to renew the backgrounds. Experimental results ances in color correction and multi-view video show the proposed method can obtain better performcoding. 展开更多
关键词 Multi-view video color correction Multi-view video coding BACKGROUND
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Emergence of Plastidial Intergenic Spacers as Suitable DNA Barcodes for Arid Medicinal Plant <i>Rhazya stricta</i>
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作者 Samia A. Khan Mohammed N. Baeshen +1 位作者 Hassan A. Ramadan Nabih A. Baeshen 《American Journal of Plant Sciences》 2017年第8期1774-1789,共16页
The desert plant Rhazya stricta has anticancer and antimicrobial properties, and is widely used in indigenous medicines of Saudi Arabia. However, the therapeutic benefits rely on an accurate identification of this spe... The desert plant Rhazya stricta has anticancer and antimicrobial properties, and is widely used in indigenous medicines of Saudi Arabia. However, the therapeutic benefits rely on an accurate identification of this species. The authenticity of R. stricta and other medicinal plants and herbs procured from local markets can be questionable due to a lack of clear phenotypic traits. DNA barcoding is an emerging technology for rapid and accurate species identification. In this study, six candidate chloroplastid barcodes were investigated for the authentication of R. stricta. We compared the DNA sequences from fifty locally collected and five market samples of R. stricta with database sequences of R. stricta and seven closely related species. We found that the coding regions matK, rbcL, rpoB, and rpoC1 were highly similar among the taxa. By contrast, the intergenic spacers psbK-psbI and atpF-atpH were variable loci distinct for the medicinal plant R. stricta. psbK-psbI clearly discriminated R. stricta samples as an efficient single locus marker, whereas a two-locus marker combination comprising psbK-psbI + atpF-atpH was also promising according to results from the Basic Local Alignment Search Tool and a maximum likelihood gene tree generated using PHyML. Two-dimensional DNA barcodes (i.e., QR codes) for the psbK-psbI and psbK-psbI + atpF-atpH regions were created for the validation of fresh or dried R. stricta samples. 展开更多
关键词 Rhazya STRICTA Medicinal Plant DNA BARCODING matK rbcl rpoB rpoC1 atpF-atpH psbK-psbI two-dimensional DNA Barcode QR code
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Research on Recognition Technology of 2-Dimensional Barcode
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作者 Ronghong Chent Qingsong Zhu 《International Journal of Technology Management》 2013年第2期1-3,共3页
This paper briefly introduces the characteristics and structure of symbol QR two-dimensional code, a detailed analysis of the image processing method to identify QR code of the whole process, and the bilinear mapping ... This paper briefly introduces the characteristics and structure of symbol QR two-dimensional code, a detailed analysis of the image processing method to identify QR code of the whole process, and the bilinear mapping method is applied to image correction, the final steps of decoding are given. The actual test results show that, the design algorithm has theoretical and practical, this recognition system can correctly read QR code, and has high recognition rate and recognition speed, has practical value and application prospect. 展开更多
关键词 two-dimensional barcode quick response code Image Recognition Technology
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iFlow彩色血流编码成像技术在下肢动脉硬化闭塞症诊断中的应用价值 被引量:1
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作者 龙海灯 殷世武 +3 位作者 潘升权 项廷淼 宋均飞 王元 《实用医学杂志》 CAS 北大核心 2024年第18期2623-2628,共6页
目的研究iFlow彩色血流编码成像技术在下肢动脉硬化闭塞症(LEASO)诊断中的应用价值。方法选择2022年3月至2023年10月期间确诊的106例LEASO患者作为本研究的LEASO组,以一般资料与LEASO组匹配且无动脉病变的80例志愿者作为对照组。两组受... 目的研究iFlow彩色血流编码成像技术在下肢动脉硬化闭塞症(LEASO)诊断中的应用价值。方法选择2022年3月至2023年10月期间确诊的106例LEASO患者作为本研究的LEASO组,以一般资料与LEASO组匹配且无动脉病变的80例志愿者作为对照组。两组受试者均进行数字减影血管造影(DSA)并采用iFlow彩色血流编码成像技术检测股骨头区域和踝关节区域达峰时间(TTP)、计算踝关节区域与股骨头区域TTP的差值,测量踝肱指数(ABI)。结果两组研究对象年龄、性别、体质量指数、吸烟史、高血压病史、糖尿病史、冠心病史、股骨头区域TTP的比较,差异无统计学意义(P>0.05);LEASO组踝关节区域TTP及TTP差值均高于对照组,差异有统计学意义(P<0.05);LEASO组中不同Rutherford分类患者股骨头区域TTP的比较以及左侧病变患者与右侧病变患者股骨头区域TTP、踝关节区域TTP、TTP差值的比较,差异无统计学意义(P>0.05),Rutherford分类越高,踝关节区域TTP及TTP差值越低(P<0.05);经Pearson检验,LEASO患者的踝关节区域TTP、TTP差值与ABI呈负相关(P<0.05);经受试者工作特征(ROC)曲线分析,踝关节区域TTP、TTP差值对LEASO具有诊断效能;经Delong检验,TTP差值诊断的ROC曲线下面积高于踝关节区域TTP(P<0.05)。结论iFlow彩色血流编码成像技术测定踝关节区TTP及TTP差值是诊断LEASO的量化指标。 展开更多
关键词 下肢动脉硬化闭塞症 iFlow彩色血流编码成像技术 达峰时间 踝关节
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Diabetes Reflect Study: Redefining Fundamental Learning of SMBG through Educational Color Tools
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作者 Katsunori Suzuki Takaaki Sato Mariko Hatta 《International Journal of Clinical Medicine》 2015年第4期227-234,共8页
Aims: To investigate the effects of a newly developed color-coded educational glucose control instruction (COLOR), combined with a color-displayed glucose meter on changes in type-2 diabetes patient’s behavior and th... Aims: To investigate the effects of a newly developed color-coded educational glucose control instruction (COLOR), combined with a color-displayed glucose meter on changes in type-2 diabetes patient’s behavior and their HbA1c levels. Material and Methods: Patients using a COLOR-self-monitoring of blood glucose (SMBG) method were instructed to record daily blood glucose levels with red (high glucose ≥ 180 mg/dL) or blue (low glucose ≤ 70 mg/dL) colored circles on their SMBG notebooks according to the colors displayed on the glucose meter. Results: COLOR-SMBG showed an improved the actual behavior modification scores by 14% compared to Conventional group at 1-month follow-up 展开更多
关键词 color-coded EDUCATIONAL GLUCOSE Control Instruction Education SMBG Type 2 DIABETES
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基于轨迹颜色编码与知识蒸馏的电能质量扰动轻量化识别方法
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作者 王守相 赵宁 +4 位作者 王同勋 郭陆阳 魏孟迪 赵倩宇 冯丹丹 《电力自动化设备》 EI CSCD 北大核心 2024年第12期85-91,共7页
当前电能质量扰动识别中存在特征混叠导致电压信号特征难以提取的问题,且电能质量识别装置部署在变电站等场所,算力较低,难以运行复杂的识别模型。为此,提出了基于轨迹颜色编码与知识蒸馏的电能质量扰动轻量化识别方法。通过圆轨迹转换... 当前电能质量扰动识别中存在特征混叠导致电压信号特征难以提取的问题,且电能质量识别装置部署在变电站等场所,算力较低,难以运行复杂的识别模型。为此,提出了基于轨迹颜色编码与知识蒸馏的电能质量扰动轻量化识别方法。通过圆轨迹转换和颜色编码,将1维电压信号转化为特征明显的彩色圆轨迹特征图,解决了特征混叠问题。使用二进制映射将特征图像降维,实现特征轻量化。构建以ResNet18为教师模型和SqueezeNext为学生模型的知识蒸馏模型,使用教师模型训练生成的软标签指导学生模型的训练,进行2个模型之间的知识迁移,实现模型压缩。为了验证所提方法的有效性和实用性,在RaspberryPi-4B边缘设备上进行验证实验,结果表明所提方法能够有效解决特征混叠问题,且识别速度相对压缩前提高了82.84%,能够满足轻量化部署的需求。 展开更多
关键词 电能质量扰动 轻量化 颜色编码 模型压缩 知识蒸馏 边缘设备
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局部编织技术的编织原理与应用
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作者 范友红 李小辉 《毛纺科技》 CAS 北大核心 2024年第3期44-50,共7页
为了对局部编织的创新设计提供理论与技术支持,基于SDS-ONE APEX3岛精服装设计系统以纬平针为地组织设计局部编织花样色码,主要从编织与休止针数变化的角度介绍局部编织技术的编织原理,提出不加不减局部编织、减针局部编织与加针局部编... 为了对局部编织的创新设计提供理论与技术支持,基于SDS-ONE APEX3岛精服装设计系统以纬平针为地组织设计局部编织花样色码,主要从编织与休止针数变化的角度介绍局部编织技术的编织原理,提出不加不减局部编织、减针局部编织与加针局部编织的工艺设计方法,并在电脑横机上编织出织片小样,进一步阐述局部编织技术在二维平面的嵌花色块拼接、镂空肌理的孔眼效应、三维立体的凹凸造型以及结构轮廓成形编织方面的应用。通过对比分析花样色码与织片小样,指出局编加减针规则与先后顺序、吊目方式、色纱组合等因素对局编织片外观的影响,对局部编织技术在针织创意花型开发与成形编织方面的应用具有指导意义。 展开更多
关键词 局部编织 编织原理 花样色码 吊目 电脑横机
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