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新型相位调制格式技术能够有效地减少光传输损伤,是光传输系统中的重要技术。从理论上分析了光MDPSK（M进制差分相移键控）的调制解调原理,构建了通用的调制解调结构,并首次推导出MDPSK的通式和解调公式,最后以基于CSRZ（载波抑制归零,占空比为67%）码的DQPSK（差分正交相移键控）、8DPSK（3阶差分相移键控）和16DPSK（4阶差分相移键控）为例,用MATLAB软件仿真得到了其调制后的频谱图和解调后的眼图。仿真结果表明,随着级数的增加,MDPSK调制格式的频谱宽度会逐渐变窄,且解调后的眼图也令人满意。

提出了一种支持服务质量（QoS）的改进JET（MJET）协议,并且提出了一种MJET突发包交换包格式、偏移时间的设置算法和节点控制算法,给出了用光混合突发交换（OCBS）实现此协议的仿真结果.

Copyright of Nonferrous Metals (Extractive Metallurgy) is the property of Beijing Research Institute of Mining & Metallurgy Technology Group and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Journal of Railway Science & Engineering is the property of Journal of Railway Science & Engineering Editorial Office and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Transactions of the Chinese Society of Agricultural Engineering is the property of Chinese Society of Agricultural Engineering and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Bulletin of the Chinese Ceramic Society is the property of Bulletin of the Chinese Ceramic Society Editorial Office and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

With the continuous expansion of the scale of bulk power grid, the operating characteristics of new power system has become more and more complex. Accurately identifying the weak links in the power grid is of great practical significance for improving the monitoring ability of the system and ensuring its reliable operation. Therefore, an identification strategy of weak links for power grid is proposed based on random matrix theory. The strategy uses the measured data in power grid operation to construct a random matrix and uses the weak links judgment index based on the random matrix theory to design the judgment method of weak nodes and weak branches. This method is analyzed from the perspective of data correlation, without considering the complex network structure and operation mechanism of the actual power grid, so there is no complex modeling process. To verify the feasibility of the method, an example simulation is established through the IEEE 39 node system and compared with the traditional methods. The results show that the proposed identification strategy has a good effect on identifying weak nodes and branches, and the accuracy is improved compared with the traditional methods. [ABSTRACT FROM AUTHOR]

Copyright of Journal of Ordnance Equipment Engineering is the property of Chongqing University of Technology and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of University Chemistry is the property of Peking University, College of Chemistry & Molecular Engineering and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Chinese Journal of Tissue Engineering Research / Zhongguo Zuzhi Gongcheng Yanjiu is the property of Chinese Journal of Tissue Engineering Research and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Feed Industry is the property of Liaoning Provincial Institute of Agricultural Mechanization and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Tunnel Construction / Suidao Jianshe (Zhong-Yingwen Ban) is the property of Tunnel Construction Editorial Office and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Chinese Journal of Inorganic Analytical Chemistry / Zhongguo Wuji Fenxi Huaxue is the property of Beijing Research Institute of Mining & Metallurgy Technology Group and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Journal of Agricultural Science & Technology (1008-0864) is the property of Journal of Agricultural Science & Technology and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Chinese Journal of Applied Mechanics is the property of Chinese Journal of Applied Mechanics Editorial Office and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Acta Agriculturae Zhejiangensis is the property of Acta Agriculturae Zhejiangensis Editorial Office and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Economic Science / Jingji Kexue is the property of Economic Science Editorial Office and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

目的　探讨管型吻合器改良腹壁通道法在腹腔镜膀胱全切-回肠膀胱术中的应用效果。方法　选取膀 胱全切-回肠膀胱术患者29例, 均使用改良腹壁通道法联合管型吻合器, 统计手术时间、出血量, 术后随访, 观察造 口旁疝的发生情况及其他远期并发症。结果 29 例手术均顺利完成。手术时间 3~9 min, 平均 4 min。出血量 2~8 mL, 平均 5 mL。围手术期无死亡病例, 1例肥胖并糖尿病患者出现造口感染。术后随访 9~34个月, 平均 17个 月, 无造口脱垂, 无造口狭窄, 2例患者出现造口旁疝, 1例为肥胖伴糖尿病并术后感染患者, 术后11个月出现造口旁 疝, 联合普外科进行手术治疗。1例为高龄并长期咳嗽患者, 术后 14个月 CT提示造口旁疝, 普外科会诊后建议观 察, 暂不需手术治疗。结论 腹腔镜膀胱全切-回肠膀胱术中应用管型吻合器改良腹壁通道法效果较好, 手术时间 短, 造口旁疝发生率低。 [ABSTRACT FROM AUTHOR]

Copyright of Atomic Energy Science & Technology is the property of Editorial Board of Atomic Energy Science & Technology and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Urban Architecture & Development is the property of Omniscient Pte. Ltd. and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

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Copyright of Feed Industry is the property of Liaoning Provincial Institute of Agricultural Mechanization and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Acta Materiae Compositae Sinica is the property of Acta Materiea Compositae Sinica Editorial Department and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Railway Construction Technology is the property of Railway Construction Technology Editorial Office and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Chinese Journal of Applied Chemistry is the property of Chinese Journal of Applied Chemistry and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Objective To evaluate the relationship between plasma heat shock protein 90α (HSP90α) levels and treatment response after four weeks and long-term prognosis after transarterial chemoembolization (TACE) of hepatocellular carcinoma (HCC). Methods The clinical data of HCC patients who underwent TACE in the Department of Interventional Radiology, Cancer Hospital of Chinese Academy of Medical Sciences from August 2017 to December 2018 were retrospectively collected. Chi-square tests were used to analyze the relationship between plasma HSP90α level and clinicopathological features before TACE treatment. Univariate and multivariate logistic regression analysis was used to analyze the influencing factors of TACE treatment response. Univariate and multivariate Cox regression analysis was used to analyze the influencing factors of progression-free survival (PFS) after TACE treatment. Results The expression level of plasma HSP90α in 96 patients before TACE treatment was (99.70 ± 66.61) ng/ml. Compared with the low HSP90α group ( n=66), the high HSP90α group ( n=30) had larger tumors, higher alpha-fetoprotein enrichment, more positive vascular invasions, and more advanced Barcelona Clinic Liver Cancer (BCLC) stages (all P<0.05). After four weeks of TACE treatment, 41 patients in the response group and 55 patients in the non-response group were evaluated. The difference of HSP90α expression levels between the response group and the non-response group before and after TACE treatment was (-32.20±22.79) ng/ml and (7.20±51.94) ng/ml, respectively, and the difference was statistically significant ( P<0.001). Multivariate logistic regression analysis showed that Child-Pugh classification ( OR=0.186, P=0.046), vascular invasion ( OR=0.132, P=0.025), and the percentage reduction of plasma HSP90α after TACE treatment (percentage reduction 25%-50%: OR=5.061, P=0.013; percentage reduction >50%: OR= 86.831, P<0.001) were independent influencing factors for the response to TACE treatment in HCC. The median PFS of the 96 patients was 8.7 months. Multivariate Cox regression analysis showed that BCLC stage (stage B: HR=2.804, P=0.008; stage C: HR=4.628, P<0.001) and the percentage reduction of plasma HSP90α after TACE treatment (percentage reduction 25%-50%: HR=0.569, P=0.051; percentage reduction >50%: HR=0.198, P<0.001) were independent influence factors for the PFS in these HCC patients after TACE treatment. [ABSTRACT FROM AUTHOR]

The banana vibration screen is widely used in the mineral processing operation process. The design of its key components affects the service life of the whole machine. Based on static analysis using ANSYS Workbench and fatigue life simulation calculation using Fatigue Tool, and the life cloud diagram of the banana screen structure components is obtained. This determines the weak link of the banana screen structure components, providing a theoretical basis for optimizing the design. [ABSTRACT FROM AUTHOR]

Copyright of Gold (1001-1277) is the property of Gold Magazine Editorial Office and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Light Industry Machinery is the property of Light Industry Machinery Editorial Office and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

The underreamed anchor is widely used in geotechnical engineering because of its advantages of large tensile capacity and high support efficiency. And the grouting length and the type of casing tube for free anchor length will affect the stress and deformation characteristics of anchor. Therefore, field experiments of underreamed anchor under different working conditions were carried out, including fixed anchor length grouting + PE corrugated tube (design scheme), full-length grouting + PE casing tube (common scheme in actual construction), fixed anchor length grouting + HDPE casing tube, full-length grouting + HDPE casing tube. The load-displacement (Q-s) curve, load-elastic displacement (Q-se) curve, load-plastic displacement (Q-sp ) curve, elongation ratio of free section and stiffness coefficient of cable under different working conditions were compared and analyzed. The test results show that compared with PE corrugated tube anchor, HDPE casing tube anchor could protect and isolate the free anchor length and ensure the deformation performance of the free anchor length under the same grouting length. When the same casing tube is used, the increase of grouting length will lead to the decrease of free anchor length elongation value, but will increase the stiffness coefficient of the underreamed anchor. On the basis of the experimental study, it is suggested that the scheme of free anchor length grouting + HDPE casing tube or full-length grouting + HDPE casing tube should be adopted in the field construction of anchor cable, so as to ensure that the stress and deformation performance of underreamed anchor meet the design expectation. [ABSTRACT FROM AUTHOR]

Copyright of Chinese Journal of Immunology is the property of Medical Periodical Society of Jilin and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Machine Tool & Hydraulics is the property of Guangzhou Mechanical Engineering Research Institute (GMERI) and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Journal of Remote Sensing is the property of Editorial Office of Journal of Remote Sensing & Science Publishing Co. and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Journal of Remote Sensing is the property of Editorial Office of Journal of Remote Sensing & Science Publishing Co. and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Journal of Remote Sensing is the property of Editorial Office of Journal of Remote Sensing & Science Publishing Co. and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

目的 分析优化溶栓流程对轻型急性缺血性卒中患者院内延误及预后的影响。 方法 回顾性收集秦皇岛市第一医院2015年7月-2017年6月行静脉溶栓治疗的轻型缺血性卒中患者 资料。按照流程优化时间前后，分为优化组和对照组。比较两组入院到溶栓时间（door to needle time， DNT）、溶栓后7 d NIHSS评分和溶栓后3个月mRS评分。 结果 共纳入57例轻型缺血性卒中患者，平均年龄61.7±5.4岁，男性44例（77.2%）。其中对照组 24例，优化组33例。两组患者一般资料比较差异无统计学意义。与对照组比较，优化组DNT缩短 （68.7±19.1 vs 88.8±23.1 mi n，P =0.001），DNT≤60 min的患者比例更高（42.4% vs 12.5%，P =0.015）； 溶栓治疗后3个月mRS评分更低[0（0～0.5）vs 0.5（0～2），P =0.017]，良好预后（mRS评分≤1分）患者 比例更高（87.9% vs 62.5%，P =0.024）。 结论 优化溶栓流程可以缩短轻型急性缺血性卒中患者的DNT，提高DNT≤60 mi n达标率，改善患者 3个月预后。 Abstract: Objective To investigate the effect of optimized thrombolysis treatment workflow on door to needle time (DNT) and prognosis in acute mild ischemic stroke patients with intravenous thrombolysis. Methods Data of mild ischemic stroke patients receiving intravenous thrombolysis from July 2015 to June 2017 in the First Qinhuangdao Hospital were retrospectively collected. According to whether thrombolysis treatment workflow was optimized or not, all patients were divided into the optimization group and the control group. Door to needle time (DNT), NIHSS score at 7 days and mRS score at 3 months after thrombolysis of two groups were compared. Results A total of 57 mild ischemic stroke patients were included, with a mean age of 61.7±5.4 years old and 44 males (77.2%). There were 33 patients in optimization group and 24 patients in control group. The general information had no statistical difference between the two groups. DNT was shorter (68.7±19.1 vs 88.8±23.1 min, P =0.001), the percentage of patients with DNT ≤60 min was higher (42.4% vs 12.5%, P =0.015), the mRS score at 3 months was lower [0 (0-0.5) vs 0.5 (0- 2), P =0.017], and the rate of patients with mRS score ≤1 at 3 months was higher (87.9% vs 62.5%, P =0.024) in optimization group, compared with that in control group. Conclusions The optimized thrombolysis treatment workflow can shorten DNT, improve the rate of DNT ≤60 min, and improve 90-day prognosis in patients with acute mild ischemic stroke.

Copyright of Mechanical & Electronic Control Engineering is the property of Omniscient Pte. Ltd. and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

In order to study the condensing heat transfer performance of the spiral tube of heat exchanger, the numerical simulation of the spiral tube of R22 refrigerant with spiral diameter was 300 mm, pitch was 19. 52 mm and pipe diameter was 9. 52 mm was carried out by using the VOF model, and the flow field distribution characteristics of the spiral tube of heat exchanger were analyzed. The influence of fluid velocity and saturation temperature on heat transfer performance of spiral tube was studied. The influence of different parameters on the heat transfer performance of the spiral tube was studied experimentally and the accuracy of the numerical simulation was verified. The experimental results show that the relative errors between the simulated and experimental data of the condensation heat transfer coefficient at different flow rates are 3% ~ 11%, and the relative errors between the simulated and experimental data of the condensation heat transfer coefficient at different saturation temperatures are 3% ~ 8%, indicating that the numerical simulation method and results are reasonable. The research results provide a certain references for the design optimization of spiral tube heat exchanger and the energy saving loss of air conditioning water heater. [ABSTRACT FROM AUTHOR]

Copyright of Journal of Vibration, Measurement & Diagnosis is the property of Nanjing Hangkong Daxue and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)