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有载分接开关防连调方式
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作者 霍锦强 《电力系统自动化》 EI CSCD 北大核心 1999年第13期53-53,共1页
近年来变电站已广泛使用有载调压变压器,有效地提高了电压质量。但由于各种原因,有载分接开关在运行中会出现连调故障,严重影响了运行安全,尤其在无人值班变电站,远方遥调对有载分接开关可靠性要求更高。由于连调故障的出现,给运... 近年来变电站已广泛使用有载调压变压器,有效地提高了电压质量。但由于各种原因,有载分接开关在运行中会出现连调故障,严重影响了运行安全,尤其在无人值班变电站,远方遥调对有载分接开关可靠性要求更高。由于连调故障的出现,给运行人员造成了很大的心理压力,严重影... 展开更多
关键词 有载分接开关 连调故障 有载调压变压器 变电站
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SYXZ型调压机构连调档位故障处理办法
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作者 王学诚 《电力安全技术》 2002年第4期36-36,共1页
关键词 有载调压变压器 SYXZ型 调压机构 连调档位 故障处理
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陕西凤翔方言两字组的连调模式 被引量:5
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作者 王军虎 《方言》 CSSCI 北大核心 2010年第3期250-254,共5页
凤翔方言的两字组可以分为后字非轻声两字组和后字轻声两字组两种,这两种连字组的连调模式不同。凤翔方言的轻声并不短而轻,其调值由前字的调类决定。凤翔方言的轻声能使前字变调。
关键词 凤翔方言 连调模式 轻声
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语流中苏州话连调的声学模式
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作者 凌锋 《语言研究集刊》 CSSCI 2014年第1期179-188,318,共12页
文章研究利用声学实验的方法,调查了苏州话连调在语流中的声学模式。结果显示,在语流中苏州话连调随着音节数的增加并没有如前人描写的那样汇聚到一个低调的位置,而是在一个音高偏中间的位置。我们认为这个位置其实是苏州话连调中弱化... 文章研究利用声学实验的方法,调查了苏州话连调在语流中的声学模式。结果显示,在语流中苏州话连调随着音节数的增加并没有如前人描写的那样汇聚到一个低调的位置,而是在一个音高偏中间的位置。我们认为这个位置其实是苏州话连调中弱化音节本身的内在音高目标,而单念时连调汇聚到低调位置其实是陈述句语调音高下倾的结果。 展开更多
关键词 连调 苏州方言 音高目标 弱化音节
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安庆方言入声EGG实验研究 被引量:4
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作者 唐志强 《南京师范大学文学院学报》 CSSCI 2016年第2期146-156,共11页
基于EGG信号,文章从时长、发声类型、代际差异及连调变异四方面实验研究安庆方言入声单、双字调,归纳出安庆方言入声变调三种类型:零型、Ⅰ型、Ⅱ型。主要结论:1)安庆方言有五个单字调:阴平、阳平、上声、去声、入声;入声调值有代际差异... 基于EGG信号,文章从时长、发声类型、代际差异及连调变异四方面实验研究安庆方言入声单、双字调,归纳出安庆方言入声变调三种类型:零型、Ⅰ型、Ⅱ型。主要结论:1)安庆方言有五个单字调:阴平、阳平、上声、去声、入声;入声调值有代际差异。2)安庆方言入声均为正常嗓音。3)安庆方言入声单、双字调已完全舒化。4)安庆方言入声仍在继续演化,有归入其他调类的可能。 展开更多
关键词 安庆方言入声 时长 发声类型 代际差异 连调变异 变调类型
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印尼华裔留学生汉语普通话双音节上上连读调偏误实验研究 被引量:16
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作者 王功平 《暨南大学华文学院学报》 2004年第4期9-20,共12页
本文通过将印尼华裔留学生和中国人的普通话双音节上上连读调发音进行对比实验,指出印尼留学生发普通话双音节上上连读调时所存在的主要偏误在于:1.调域偏小;2.最大音高值偏低;3.音节发音时长偏长,且前后字时长比例不当。并进而分析了... 本文通过将印尼华裔留学生和中国人的普通话双音节上上连读调发音进行对比实验,指出印尼留学生发普通话双音节上上连读调时所存在的主要偏误在于:1.调域偏小;2.最大音高值偏低;3.音节发音时长偏长,且前后字时长比例不当。并进而分析了产生这些偏误的主要原因,提出了相应的纠正措施。 展开更多
关键词 印尼华裔留学生 上上连调 偏误
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山西壶关南部方言两字组连读变调
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作者 李晰 《山西师大学报(社会科学版)》 2019年第3期106-112,共7页
壶关南部方言有8个单字调,64种两字组排列,93种连调式。在93种连调式中,45种有变调,48种没有变调。45种有变调的连调式,连同48种没有变调的连调式,合并成18种连调式。从变调的位置看,壶关南部方言属前后均变型连读变调;从变调的结果看,... 壶关南部方言有8个单字调,64种两字组排列,93种连调式。在93种连调式中,45种有变调,48种没有变调。45种有变调的连调式,连同48种没有变调的连调式,合并成18种连调式。从变调的位置看,壶关南部方言属前后均变型连读变调;从变调的结果看,壶关南部方言属调值循环型连读变调;从参加变调的单字调看,壶关南部方言属全部变调型连读变调。壶关南部方言的连读变调与语法结构有一定的关系,大致是谓词性结构不变调,名词性结构变调。壶关南部方言古去声字今读阴去、阳去,阴去有读同阳去的现象,但不多见。但在连调式中,阴阳去有明显的合并趋势,方向是阴去合并到同阳去。壶关南部方言的阴去将来可能会在连读变调的影响下变同阳去,形成只有一个去声的局面。 展开更多
关键词 壶关南部方言 两字组 连调
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Continuous extrusion and rolling forming velocity of copper strip 被引量:10
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作者 运新兵 游伟 +2 位作者 赵颖 李冰 樊志新 《Transactions of Nonferrous Metals Society of China》 SCIE EI CAS CSCD 2013年第4期1108-1113,共6页
A new copper strip production technology combined with continuous extrusion and rolling technology was proposed. The roll velocity must first be matched with the continuous extrusion velocity to achieve continuous ext... A new copper strip production technology combined with continuous extrusion and rolling technology was proposed. The roll velocity must first be matched with the continuous extrusion velocity to achieve continuous extrusion and roll forming. The bite condition of continuous extrusion was determined, and the compatibility equation between the roll velocity and parameters such as the extrusion wheel velocity, reduction, and strip size was established through mechanical by plastic theoretical calculations. The finite element model of continuous extrusion and rolling was then established by using the TLJ400 continuous extrusion machine with a roll diameter of 200 mm. The relationship between the continuous extrusion and rolling velocities was determined through numerical simulations by software DEFORM-3D, and the accuracy of compatibility equation of velocity was verified. 展开更多
关键词 copper strip continuous extrusion and rolling bite condition compatibility equation of velocity
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Scheduling method for single-arm cluster tools of wafer fabrications with residency and continuous reentrancy 被引量:2
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作者 周炳海 王翥 陈佳 《Journal of Southeast University(English Edition)》 EI CAS 2013年第2期187-193,共7页
In order to enhance the utilization of single-ann cluster tools and optimize the scheduling problems of dynamic reaching wafers with residency time and continuous reentrancy constraints, a structural heuristic schedul... In order to enhance the utilization of single-ann cluster tools and optimize the scheduling problems of dynamic reaching wafers with residency time and continuous reentrancy constraints, a structural heuristic scheduling algorithm is presented. A nonlinear programming scheduling model is built on the basis of bounding the scheduling problem domain. A feasible path search scheduling method of single-arm robotic operations is put forward with the objective of minimal makespan. Finally, simulation experiments are designed to analyze the scheduling algorithms. Results indicate that the proposed algorithm is feasible and valid to solve the scheduling problems of multiple wafer types and single-ann clusters with the conflicts and deadlocks generated by residency time and continuous reentrancy constraints. 展开更多
关键词 cluster tools SCHEDULING residency time continuous reentrancy
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江淮官话洪巢片的入声变异
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作者 唐志强 《安庆师范大学学报(社会科学版)》 2021年第6期50-55,共6页
基于EGG信号,采用实验语音学技术,研究江淮官话洪巢片入声单、双字调,归纳出入声连读变调有零、Ⅰ、Ⅱ三种类型。根据入声连读变调及单字调系统,揭示了江淮官话洪巢片入声发展的三个阶段:阶段一(南京)→阶段二(扬州、芜湖)→阶段三(盐... 基于EGG信号,采用实验语音学技术,研究江淮官话洪巢片入声单、双字调,归纳出入声连读变调有零、Ⅰ、Ⅱ三种类型。根据入声连读变调及单字调系统,揭示了江淮官话洪巢片入声发展的三个阶段:阶段一(南京)→阶段二(扬州、芜湖)→阶段三(盐城、合肥)。依据各阶段入声连调变异调值推衍出入声演变路径,并指出洪巢片入声变异同时沿袭音区调整及改变曲拱两条途径。 展开更多
关键词 江淮官话洪巢片 入声 变调类型 连读变调 连调变异
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Investigation and Analysis of Continuous Cropping of Flue-cured Tobacco in Henan Province
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作者 陈继峰 蔡凯旋 +4 位作者 孙会 赵松辉 刘洪源 石礼森 郑亚楠 《Agricultural Science & Technology》 CAS 2016年第8期1808-1812,1888,共6页
The continuous cropping of flue-cured tobacco in the major producing areas of Henan Province by designing questionnaire, fieldwork, enquiry and phone calls, mails, and other forms, the data were obtained then classifi... The continuous cropping of flue-cured tobacco in the major producing areas of Henan Province by designing questionnaire, fieldwork, enquiry and phone calls, mails, and other forms, the data were obtained then classified and analyzed. The results showed that the main planting areas of flue-cured tobacco were in Nanyang, Xuchang, Luoyang, Sanmenxia, Pingdingshan, and Luohe where were the major producing areas of succession cropping of flue-cured tobacco with percentage of 20%-40% for three years and over three years, and a few places up to 50%. Morbidity was common with wide distribution, and the main diseases were black shank, viral disease, and black rot. It proved that tobacco was not suitable for continuous cropping. Both of tobacco disease and pest rate and mortality significantly increased by more than 40% under continuous cropping for three years and over three years, and the yield and quality of flue-cured tobacco also decreased after continuous cropping. For many places, the tobacco yield started to decrease in the second year of continuous cropping, and after three-year cropping, the yield decreased in the range of 9%-24%. Continuous cropping for a long time would make a serious decline in the quality of tobacco, resulting in non-economic benefits. Therefore, in order to reduce the occurrence of diseases and economic loss in tobacco production, it is recommended to avoid continuous cropping, or to adopt appropriate measures to control tobacco continuous cropping obstacles in the unavoidable case. 展开更多
关键词 Flue-cured tobacco Continuous cropping YIELD QUALITY Diseases and pests INVESTIGATION Henan province
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赣语樟树方言两字组中的轻声
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作者 习晨 《文山学院学报》 2019年第5期83-86,共4页
通过收集樟树方言里轻声的语料,并对樟树方言的轻声进行分类,可以发现樟树方言中轻声情况比较复杂,兼有自主和非自主变轻声、调值和调类轻声。另外,两字组中的轻声有其出现的语法和语义条件:如大多数偏正式、并列式后字,词缀,动词后的... 通过收集樟树方言里轻声的语料,并对樟树方言的轻声进行分类,可以发现樟树方言中轻声情况比较复杂,兼有自主和非自主变轻声、调值和调类轻声。另外,两字组中的轻声有其出现的语法和语义条件:如大多数偏正式、并列式后字,词缀,动词后的趋向动词等都念轻声。与北京话轻声相同,樟树方言两字组中的轻声也能区分字形相同的词或词组的语法性质和意义。 展开更多
关键词 轻声 连读变调 连调模式
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Concatenated Trellis Coding and CPM for DS/SSMA Communications in Rayleigh Fading Channel
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作者 仰枫帆 梁树雄 毕光国 《Journal of Southeast University(English Edition)》 EI CAS 1999年第1期9-16,共8页
In this paper, direct sequence spread spectrum multiple access (DS/SSMA) communication system employing serially concatenated trellis coded modulation (TCM) and continuous phase modulation (CPM) over flat Rayleigh fa... In this paper, direct sequence spread spectrum multiple access (DS/SSMA) communication system employing serially concatenated trellis coded modulation (TCM) and continuous phase modulation (CPM) over flat Rayleigh fading channel are presented. The performance of this concatenated TCM/CPM DS/SSMA system is exploited by the theoretical analysis and numerical simulations. The results demonstrate that significant improvements in error probability of this DS/SSMA system over the system with single TCM or CPM of different modulation indices can be achieved under the same conditions. 展开更多
关键词 concatenated TCM/CPM direct sequence spread spectrum multiple access Rayleigh fading channel
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A Novel Digital Transceiver for CT0 Standard 被引量:1
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作者 陈殿玉 许长喜 +7 位作者 陈浩琼 李振 郭秀丽 惠志强 施鹏 王跃 吴岳 熊绍珍 《Journal of Semiconductors》 EI CAS CSCD 北大核心 2007年第6期833-841,共9页
This paper introduces a novel digital transceiver for the cordless telephone zero (CT0) standard,which uses a digital modulation and demodulation technique to handle the signal instead of the traditional analog meth... This paper introduces a novel digital transceiver for the cordless telephone zero (CT0) standard,which uses a digital modulation and demodulation technique to handle the signal instead of the traditional analog meth-od. In the transmitter,a fractional-N phase locked loop (PLL) is utilized to realize the continuous phase frequency shift key (CPFSK) modulation,and a 2 Ts raised cosine (2RC) shaping technique is used to reduce the occupied bandwidth. In the receiver,a novel digital method is proposed to demodulate the 2RC CPFSK signal. This chip is fabricated using an SMIC 0.35μm mixed signal CMOS process with a die size of 2mm × 2mm. With an external low noise amplifier (LNA),the sensitivity of the chip is better than -103dBm. 展开更多
关键词 RF transceiver fractional-N PLL CPFSK MODULATOR DEMODULATOR
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The Extension of Continuous Measure
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作者 彭祖赠 孙韫玉 《Chinese Quarterly Journal of Mathematics》 CSCD 1992年第3期88-94,共7页
In this paper we give a sufficient and necessary condition under which a continuous measure (whose values belong to, the extended half-line (0,+∞) defined on a class of sets closed under the formation of intersection... In this paper we give a sufficient and necessary condition under which a continuous measure (whose values belong to, the extended half-line (0,+∞) defined on a class of sets closed under the formation of intersection can be extended to a smallest monotone class containing this class, and we also give a condition under which there exists a unique extension. In addition, we give a method by means of which a continuous measure on a monotone class can be extended again. 展开更多
关键词 continuous measure complete partition basic continuous extension
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Berberine induces cell cycle arrest and apoptosis in human gastric carcinoma SNU-5 cell line 被引量:36
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作者 Jing-Pin Lin Jai-Sing Yang +2 位作者 Jau-Hong Lee Wen-Tsong Hsieh Jing-Gung Chung 《World Journal of Gastroenterology》 SCIE CAS CSCD 2006年第1期21-28,共8页
AIM: To investigate the relationship between the inhibited growth (cytotoxic activity) of berberine and apoptotic pathway with its molecular mechanism of action. METHODS: The in vitro cytotoxic techniques were com... AIM: To investigate the relationship between the inhibited growth (cytotoxic activity) of berberine and apoptotic pathway with its molecular mechanism of action. METHODS: The in vitro cytotoxic techniques were complemented by cell cycle analysis and determination of sub-G1 for apoptosis in human gastric carcinoma SNU-5 cells. Percentage of viable cells, cell cycle, and sub431 group (apoptosis) were examined and determined by the flow cytometric methods. The associated proteins for cell cycle arrest and apoptosis were examined by Western blotting. RESULTS: For SNU-5 cell line, the IC (50) was found to be 48 μmol/L of berberine. In SNU-5 cells treated with 25-200 μmol/L berberine, G2/M cell cycle arrest was observed which was associated with a marked increment of the expression of p53, Wee1 and CDk1 proteins and decreased cyclin B. A concentration-dependent decrease of cells in G0/G1 phase and an increase in G2/M phase were detected. In addition, apoptosis detected as sub-Go cell population in cell cycle measurement was proved in 25-200 μmol/L berberine-treated cells by monitoring the apoptotic pathway. Apoptosis was identified by sub-Go cell population, and upregulation of Bax, downregulation of Bcl-2, release of Ca^2+, decreased the mitochondrial membrane potential and then led to the release of mitochondrial cytochrome C into the cytoplasm and caused the activation of caspase-3, and finally led to the occurrence of apoptosis. CONCLUSION: Berberine induces p53 expression and leads to the decrease of the mitochondrial membrane potential, Cytochrome C release and activation of caspase-3 for the induction of apoptosis. 展开更多
关键词 BERBERINE Cell cycle APOPTOSIS Caspase-3 ROS MMP SNU-5 cells
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SERIALLY CONCATENATED CONTINUOUS PHASE MODULATION WITH REDUCED ITERATIVE DEMODULATION AND DETECTION 被引量:3
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作者 Sun Jinhua Li Jiandong Jin Lijun 《Journal of Electronics(China)》 2007年第1期16-22,共7页
A reduced state Soft Input Soft Output (SISO) a posteriori probability algorithm for Seri-ally Concatenated Continuous Phase Modulation (SCCPM) is proposed in this paper. Based on the Reduced State Sequence Detection ... A reduced state Soft Input Soft Output (SISO) a posteriori probability algorithm for Seri-ally Concatenated Continuous Phase Modulation (SCCPM) is proposed in this paper. Based on the Reduced State Sequence Detection (RSSD),it has more general form compared with other reduced state SISO algorithms. The proposed algorithm can greatly reduce the state number,thus leads to the computation complexity reduction. It also minimizes the degradation in Euclidean distance with decision feedback in the reduced state trellis. Analysis and simulation results show that the perform-ance degradation is little with proper reduction scheme. 展开更多
关键词 Concatenated codes Continuous Phase Modulation (CPM) Soft Input Soft Output (SISO) Euclidean distance
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Continuous rotation north-finding algorithm based on constrained adaptive Kalman filter 被引量:2
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作者 GUO Fengzhi LI Xingfei LI Jingxian 《Journal of Measurement Science and Instrumentation》 CAS CSCD 2021年第2期133-145,共13页
As an orientation measurement system,north-finder has been playing a significant role in both military and civilian fields of orientation and control.In this paper,to deal with drawbacks in the conventional north-find... As an orientation measurement system,north-finder has been playing a significant role in both military and civilian fields of orientation and control.In this paper,to deal with drawbacks in the conventional north-finding systems,a dynamic strategy based on continuous rotation modulation to measure the rotational angular velocity of the earth is proposed.By modeling the dynamic error,optimizing the process constraint and estimating dynamic noise,a method combining delay compensation and hardware adjustment,and a constrained adaptive Kalman filter(CAKF)algorithm are designed for the north-finding strategy.According to simulation and experiments,the proposed algorithm can achieve the high-precision north-finding with robust and anti-noise performance. 展开更多
关键词 north-finding constrained adaptive Kalman filter(CAKF) continuous rotation modulation dynamic error tilted base
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Design of Demodulation System of Interferometric Sensor Based on Labview 被引量:3
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作者 XU Wei WANG Jin-hai +2 位作者 CHEN Cai-he ZHENG Yu ZHANG Cheng 《Semiconductor Photonics and Technology》 CAS 2008年第2期115-120,共6页
For the modified demodulation arithmetic of 3×3 coupler, the processing software built on the basis of Labview is able to demodulate asymmetric 3×3 coupler signal and do further spectrum analysis. It shows t... For the modified demodulation arithmetic of 3×3 coupler, the processing software built on the basis of Labview is able to demodulate asymmetric 3×3 coupler signal and do further spectrum analysis. It shows that the measured frequency ranges from 10 Hz to 1 000 Hz and phase range is covered by -10 rad^10 rad. The phase sensitivity is 0.5 V/rad. This system is proved to show high resolution and wide dynamic range. 展开更多
关键词 asymmetric 3×3 coupler phase demodulation LABVIEW software demodulation interferometric sensor
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Coordinated node scheduling for energy-conserving in large wireless sensor networks
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作者 石高涛 廖明宏 徐文旭 《Journal of Harbin Institute of Technology(New Series)》 EI CAS 2008年第4期558-563,共6页
Aiming at developing a node scheduling protocol for sensor networks with fewer active nodes,we propose a coordinated node scheduling protocol based on the presentation of a solution and its optimization to determine w... Aiming at developing a node scheduling protocol for sensor networks with fewer active nodes,we propose a coordinated node scheduling protocol based on the presentation of a solution and its optimization to determine whether a node is redundant.The proposed protocol can reduce the number of working nodes by turning off as many redundant nodes as possible without degrading the coverage and connectivity.The simulation result shows that our protocol outperforms the peer with respect to the working node number and dynamic coverage percentage. 展开更多
关键词 CONNECTIVITY COVERAGE node scheduling energy efficiency wireless sensor networks
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