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Channel puncturing based low-complexity belief propagation detection for multi-user MIMO systems

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The Journal of China Universities of Posts and Telecommunications 2020年第6期27卷 8-16页

作者： Cai xingwei ji Wei qiu Ling Liang Xiaowen Key Laboratory of Wireless-Optical Communications Chinese Academy of SciencesSchool of Information Science and TechnologyUniversity of Science and Technology of ChinaHefei 230026China

A low complexity punctured belief propagation(BP)detection utilizing channel puncturing for multi-user multiple-input multiple-output(MU-MIMO)systems is proposed in this *** paper constructs a cycle-free fator graph by puncturing certain non-zero entries in a transformed channel matrix,and proposes an adjusted BP algorithm with a more exact a posteriori message updating *** proposed algorithm converges rapidly in several iterations due to the cycle-free structure in the factor ***,puncturing brings distorted noise and thus leads to performance *** tackle this issue,this article further designs a layered detection with the help of maximum likelihood detector(MLD).Simulations demonstrate that the proposed detection algorithm achieves the identical performance to MLD with much lower complexity.

关键词： MU-MIMO rich scattering wireless environment BP layered detection algorithm

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城市地下综合管廊日常维护费测算研究

价值工程 2024年第26期43卷 23-26页

作者：邱国荣陈集鹏珠海市香洲区政府投资项目审核中心珠海519000 广州市国际工程咨询有限公司广州510600

随着已建成运营或正在(规划)建设的管廊数量不断增加,范围不断扩大,各地在处理管廊日常维护费时面临较大压力,如何合理测算日常维护费并划分管线单位分摊比例,成为亟待解决的重要问题。本文将以某城市综合管廊为例,根据2023年底两部委... 详细信息

随着已建成运营或正在(规划)建设的管廊数量不断增加,范围不断扩大,各地在处理管廊日常维护费时面临较大压力,如何合理测算日常维护费并划分管线单位分摊比例,成为亟待解决的重要问题。本文将以某城市综合管廊为例,根据2023年底两部委联合印发的《关于做好城市地下综合管廊收费有关工作的通知》精神,采用“按舱分摊”“平均分摊”模型测算管廊案例各类管线日常维护费的分摊比例,分析分摊模型的适用范围,为其他城市的管廊日常维护费分摊提供参考。

关键词：城市地下综合管廊日常维护费测算研究

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凡纳滨对虾盐碱水养殖池塘沉积物-水界面氮元素交换通量的研究

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水生生物学报 2024年第7期48卷 1183-1192页

作者：杜彦秋吴文广张子军吴桃冯旭张继红上海海洋大学水产与生命学院上海201306 中国水产科学研究院黄海水产研究所青岛海洋科学与技术试点国家实验室海洋渔业科学与食物产出过程功能实验室青岛266071 鄂尔多斯市农牧技术推广中心鄂尔多斯017000

为探究凡纳滨对虾(Litopenaeus vannamei)盐碱水养殖池塘沉积物-水界面中氮元素的转化规律,于2019年5—7月测定了山东省滨州市3个不同盐度(28、45和55)的池塘上覆水和沉积物间隙水中各种形态氮的含量。利用Fick第一定律估算了池塘沉积物... 详细信息

为探究凡纳滨对虾(Litopenaeus vannamei)盐碱水养殖池塘沉积物-水界面中氮元素的转化规律,于2019年5—7月测定了山东省滨州市3个不同盐度(28、45和55)的池塘上覆水和沉积物间隙水中各种形态氮的含量。利用Fick第一定律估算了池塘沉积物-水界面氮元素交换通量,分析了环境因素与交换通量的相关性。结果表明:(1)总体来讲,DIN、DON、TN由沉积物向水体扩散,即沉积物为DIN、DON和TN的源;NO_(3)^(-)-由水体向沉积物扩散,沉积物为NO_(3)^(-)的汇。在养殖期间,盐度28、45和55组,DIN总交换通量分别为1.69、23.07和19.36 mg/m^(2),DON总交换通量分别为36.60、27.90和19.98 mg/m^(2),TN总交换通量分别为38.09、43.66和32.56 mg/m^(2)。(2)从季节变化来看,DIN、DON、TN在养殖初期(5月)的交换通量显著高于养殖末期(7月);从盐度组来看,在5月,盐度28、45和55组,DIN平均交换通量分别为2.08、6.37和12.47 mg/(m^(2)·d),7月分别为-0.48、0.06和1.47 mg/(m^(2)·d),盐度55组显著大于其他两组(P<0.05);DON交换通量5月分别为13.91、5.32和6.79 mg/(m^(2)·d),盐度28组显著大于其他两组(P<0.05),7月分别为5.82、10.94和5 mg/(m^(2)·d),盐度45组显著大于其他两组(P<0.05);5月TN平均交换通量分别为15.9、8.79和19.16 mg/(m^(2)·d),盐度45组显著小于其他两组(P<0.05),7月分别为5.31、9.1和3.28 mg/(m^(2)·d),盐度45组显著大于盐度55组(P<0.05)。(3)冗余分析结果显示,盐度与NO_(2)^(-)-N、NO_(3)^(-)-N、NH_(4)^(+)-N交换通量显著正相关;有机质与NH_(4)^(+)、TN通量显著正相关;温度与NH_(4)^(+)交换通量显著负相关;含水率、孔隙度与NO_(3)^(-)-N、DON交换通量显著正相关。综上所述,沉积物是氮的潜在污染源,此污染潜力在养殖末期显著小于养殖初期;高盐度组有利于释放DIN,中低盐度组有利于释放DON。研究结果将有助于认识盐碱水养殖池塘的氮交换通量,为该种养殖模式的科学管理提供数据支撑。

关键词：盐碱水池塘沉积物-水界面氮凡纳滨对虾

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Inguinal and subinguinal micro-varicocelectomy, the optimal surgical management of varicocele： a meta-analysis

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Asian Journal of Andrology 2015年第1期17卷 74-80,I0008页

作者： Jun Wang Shu-jie Xia Zhi-Hong Liu Le Tao ji-Fu Ge Chen-Min Xu jian-xin qiu Department of Urology Shanghai First People's Hospital Medical College of Shanghai Jiao Tong University Shanghai China.

Conventional meta-analyses have shown inconsistent results for the efficacy of various treatments of varicoceles. Therefore, we performed a multiple-treatment meta-analysis to assess the effectiveness and safety of 10 methods of varicocelectomy and embolization/sclerotherapy. We systematically reviewed 35 randomized controlled trials and observational studies, from 1966 to August 5, 2013, which compared any of the following treatments for varococeles： laparoscopic, retroperitoneal, open inguinal and subinguinal varicocelectomy, microsurgical subinguinal and inguinal varicocelectomy, percutaneous venous embolization, Tauber antegrade sclerotherapy, retrograde sclerotherapy and expectant therapy （no treatment）. Inguinal and subinguinal microsurgery, open inguinal, laparoscopic varicocelectomy showed a significant advantage over expectant therapy in terms of pregnancy rates （odds ratio （OR）： 3.48, 2.68, 2.92 and 2.90, respectively）. Compared with retroperitoneal open surgery, inguinal microsurgery showed an improvement of sperm density （mean difference （MD）： 10.60, 95% confidence interval （Cl）： 1.92-19.60） and sperm motility （MD： 9.09, 95% Cl. 4.88-13.30）. Subinguinal and inguinal microsurgery outperformed retroperitoneal open surgery in terms of recurrence （OR： 0.05, 0.06 respectively）. Tauber antegrade sclerotherapy and subinguinal microsurgery were associated with the lowest risk of hydrocele formation. The odds of overall complication, compared with retroperitoneal open varicocelectomy, were lowest for inguinal microsurgery （OR = 0.07, 95% Ch 0.02-0.19）, followed by subinguinal microsurgery （OR = 0.09, 95% CI. 0.02-0.19）. Inguinal and subinguinal micro-varicocelectomy had the highest pregnancy rates, significant increases in sperm parameters, with low odds of complication. These results warrant additional properly conducted randomized controlled clinical studies with larger sample sizes.

关键词： meta-analysis varicocele varicocelectomy

紫花地丁活性成分、药理作用及其在畜禽生产方面的应用前景

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中国兽药杂志 2024年第5期58卷 89-94页

作者：丘跃济李美娣吉艺宽广东梅州职业技术学院梅州市中兽药工程技术研究中心广东梅州514011

紫花地丁作为我国传统的药食同源的多年生草本植物,主治目赤肿痛、疔疮肿毒、乳房炎、毒蛇咬伤的疾病,内含丰富的黄酮苷类、香豆素类化合物,具有抗炎抗菌,抗病毒等多种药理活性。本文主要就近年来国内外对紫花地丁的物质基础及应用于畜... 详细信息

紫花地丁作为我国传统的药食同源的多年生草本植物,主治目赤肿痛、疔疮肿毒、乳房炎、毒蛇咬伤的疾病,内含丰富的黄酮苷类、香豆素类化合物,具有抗炎抗菌,抗病毒等多种药理活性。本文主要就近年来国内外对紫花地丁的物质基础及应用于畜禽生产上的研究成果进行综述,为下一步提取紫花地丁有效成分以及用于家禽养殖创新用药的试验研究、开发和利用提供参考依据。

关键词：紫花地丁生物学活性畜禽生产兽用中药

The synthetic strategies of hierarchical TS-1 zeolites for the oxidative desulfurization reactions

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Chinese Journal of Chemical Engineering 2020年第9期28卷 2227-2234页

作者： Guoju Yang ji Han Yue Liu Ziyi qiu Xiaoxin Chen State Key Laboratory of Inorganic Synthesis and Preparative Chemistry College of ChemistryJilin UniversityChangchun 130012China International Center of Future Science Jilm UniversityChangchun 130012China Department of Chemistry and Catalysis Research Center Technische Universitat MunchenLichtenbergstrasse 485747 GarchingGermany

With the increasingly stringent standards for limiting sulfide content in liquid fuels,oxidative desulfurization(ODS)has become a promising ultra-deep desulfurization process in fuel ***-1 zeolites show great potential as catalysts for ODS reactions,due to its remarkable oxidation activity at low temperatures and ***,the inherent microporous structure of conventional TS-1 zeolites restricts the mass transportation and renders the active sites in the microporous space of TS-1 zeolites inaccessible for bulky aromatic organosulfur *** of hierarchical TS-1 zeolites by incorporating meso-/macropores into microporous TS-1 zeolites is an effective strategy to improve mass *** recent years,abundant efforts have been dedicated to developing synthetic strategies of hierarchical TS-1 zeolite,thereby improving its catalytic performance in the ODS *** mini-review addresses the synthetic methods of hierarchical TS-1 catalysts and their catalytic performance in the ODS *** addition,some current problems and prospects of synthesis routes for constructing hierarchical TS-1 catalysts have also been *** expect this mini-review to shed light on the more efficient preparation strategies of hierarchical TS-1 zeolites for the ODS process.

关键词： Zeolites TS-1 Synthesis Hierarchical ODS

Effects of Dissimilar Alumina Particulates on Microstructure and Properties of Cold-Sprayed Alumina/A380 Composite Coatings

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Acta Metallurgica Sinica(English Letters) 2019年第12期32卷 1449-1458页

作者： Xiang qiu Naeem ul Haq Tariq Lu Qi Jun-Rong Tang xin-Yu Cui Hao Du ji-Qiang Wang Tian-Ying Xiong Institute of Metal Research Chinese Academy of SciencesShenyang 110016China School of Materials Science and Engineering University of Science and Technology of ChinaShenyang 110016China University of Chinese Academy of Sciences No.19(A)Yuquan RoadShijingshan DistrictBeijing 100049China Department of Metallurgy and Materials Engineering Institute of Engineering and Applied SciencesNiloreIslamabadPakistan

In this study,alumina/A380 composite coatings were fabricated by cold *** influence of alumina particulates,morphology(spherical and irregular)and content on the deposition behavior of the coatings(including surface roughness,surface residual stress,cross-sectional microstructure and microhardness)was *** revealed that the spherical alumina mainly shows micro-tamping effect during deposition,which result in remarkable low surface roughness and porosity of the *** addition,very low deposition efficiency and good interfacial bonding between the coating and the substrate were *** irregular alumina particles,the embedding of ceramic particulates in the coating was dominant during deposition process,resulting in high retention in the final ***,it showed limited influence on porosity,surface roughness and interfacial bonding of the *** coatings containing irregular alumina particulates exhibited much higher microhardness than those containing spherical alumina due to the higher load-bearing capacity of deposited alumina.

关键词： Cold spray Alumina particles Microstructure Micro-tamping effect Embedding effect

Cu含量对电弧熔丝增材制造Al-Cu合金高温组织与性能的影响

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兵器材料科学与工程 2024年第4期47卷 92-97页

作者：邱相儒王帅及红娟韩志远明珠北京航天长征飞行器研究所北京100076 中国兵器科学研究院宁波分院浙江宁波315103

为研究Cu含量对电弧熔丝增材制造Al-Cu合金堆积体高温组织与性能的影响,对Al-Cu合金堆积进行200℃保温30 min处理,通过金相、SEM、EDS及拉伸试验,分析其显微组织和力学性能。结果表明:高温下随Cu的质量分数由5%增至6.3%,Al-Cu合金堆积... 详细信息

为研究Cu含量对电弧熔丝增材制造Al-Cu合金堆积体高温组织与性能的影响,对Al-Cu合金堆积进行200℃保温30 min处理,通过金相、SEM、EDS及拉伸试验,分析其显微组织和力学性能。结果表明:高温下随Cu的质量分数由5%增至6.3%,Al-Cu合金堆积体晶粒尺寸无变化,未固溶θ相的数量增多、尺寸增大;晶粒内部平衡θ相的数量先增多后稳定变化;Al-Cu合金堆积体高温力学性能先升后降,Cu的质量分数为5.65%的Al-Cu合金堆积体具有最优的力学性能,抗拉强度为355 MPa,屈服强度为345 MPa,伸长率为6.5%。

关键词：电弧增材制造 Al-Cu合金高温组织和性能

铁铜基粉末冶金材料制动工况下的摩擦磨损性能

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粉末冶金技术 2024年第4期42卷 354-360页

作者：马玲徐岩杜建华韩明邱倩张楠纪箴北京科技大学材料科学与工程学院北京100083 北京理工大学机械与车辆学院北京100081 中国兵器科学研究院北京100089 宿州学院化学化工系宿州234000 中国北方车辆研究所北京100072

采用MM3000型摩擦磨损试验机,在7种连续制动工况下分别测试铁铜基粉末冶金摩擦材料的摩擦性能和耐热性能,利用扫描电镜和能谱仪分析研究两种转速(等效半径线速度)下摩擦材料的磨损机理。结果表明:在线速度为19.40 m·s^(-1)时,随着面压... 详细信息

采用MM3000型摩擦磨损试验机,在7种连续制动工况下分别测试铁铜基粉末冶金摩擦材料的摩擦性能和耐热性能,利用扫描电镜和能谱仪分析研究两种转速(等效半径线速度)下摩擦材料的磨损机理。结果表明:在线速度为19.40 m·s^(-1)时,随着面压增加,摩擦材料的动摩擦系数略有降低。在0.44 MPa面压下,动摩擦系数为0.267~0.312;在0.80 MPa面压下,动摩擦系数为0.258~0.308。在线速度19.40 m·s^(-1)、面压0.44 MPa、单位面积制动能量268 J·cm^(-2)的连续制动工况条件下,动摩擦系数波动较大,在其他工况条件下,动摩擦系数波动较小。随着制动能量的增加,7种连续制动工况下平均动摩擦系数在0.300~0.334之间,动摩擦系数均在0.250以上,无明显衰退现象,表明铁铜基粉末冶金摩擦材料具有较好的耐热性能。在线速度为19.40 m·s^(-1)工况下,铁铜基摩擦材料的摩擦磨损机理主要为磨料磨损及氧化磨损;在线速度为30.00 m·s^(-1)工况下,铁铜基摩擦材料的摩擦磨损机理主要为疲劳磨损及氧化磨损。

关键词：铁铜基粉末冶金摩擦材料连续制动工况摩擦性能耐热性能磨损机理