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Prediction of massive transfusion in trauma patients in the surgical intensive care units (THAI-SICU study)
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作者 Osaree Akaraborworn Onuma Chaiwat +8 位作者 Sunisa Chatmongkolchart Chanatthee Kitsiripant Kaweesak Chittawatanarat Sunthiti Morakul Thammasak Thawitsri Petch Wacharasintg Sujaree Poopipatpab Waraporn Chau-In Chaiyapruk Kusumaphanyo 《中华创伤杂志:英文版》 CAS CSCD 2019年第4期219-222,共4页
Purpose: After damage control surgery, trauma patients are transferred to intensive care units to restore the physiology. During this period, massive transfusion might be required for ongoing bleeding and coagulopathy... Purpose: After damage control surgery, trauma patients are transferred to intensive care units to restore the physiology. During this period, massive transfusion might be required for ongoing bleeding and coagulopathy. This research aimed to identify predictors of massive blood transfusion in the surgical intensive care units (SICUs). Methods: This is an analysis of the THAI-SICU study which was a prospective cohort that was done in the 9-university-based SICUs in Thailand. The study included only patients admitted due to trauma mechanisms. Massive transfusion was defined as received >10 units of packed red blood cells on the first day of admission. Patient characteristics and physiologic data were analyzed to identify the potential factors. A multivariable regression was then performed to identify the significant model. Results: Three hundred and seventy patients were enrolled. Sixteen patients (5%) received massive transfusion in the SICUs. The factors that significantly predicted massive transfusion were an initial sequential organ failure assessment (SOFA)>9 (risk difference (RD) 0.13, 95% confidence interval (CI): 0.03—0.22, p = 0.01);intra-operative blood loss > 4900 mL (RD 0.33, 95% CI: 0.04—0.62, p = 0.02) and intra-operative blood transfusion > 10 units (RD 0.45, 95% Cl: 0.06 to 0.84, p = 0.02). The probability to have massive transfusion was 0.976 in patients who had these 3 factors. Conclusion: Massive blood transfusion in the SICUs occurred in 5%. An initial SOFA >9, intra-operative blood loss >4900 mL, and intra-operative blood transfusion >10 units were the significant factors to predict massive transfusion in the SICUs. 展开更多
关键词 MASSIVE TRANSFUSION MASSIVE BLEEDING SURGICAL INTENSIVE care Multiple TRAUMA
基于平行因子分解的大规模MIMO盲信道估计 预览
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作者 赵凌霄 赵家乐 +1 位作者 张建康 穆晓敏 《电讯技术》 北大核心 2019年第2期199-204,共6页
针对单小区大规模多输入多输出(Multiple-Input Multiple-Output,MIMO)系统上行链路,提出了一种基于平行因子(Parallel Factor,PARAFAC)模型的信道估计方法。在基站端,将接收信号构造成PARAFAC模型,利用大规模MIMO系统中信道的渐近正交... 针对单小区大规模多输入多输出(Multiple-Input Multiple-Output,MIMO)系统上行链路,提出了一种基于平行因子(Parallel Factor,PARAFAC)模型的信道估计方法。在基站端,将接收信号构造成PARAFAC模型,利用大规模MIMO系统中信道的渐近正交的性质,提出了一种基于约束二线性迭代最小二乘算法(Constrained Blinear Alternating Least Squares,CBALS),从而实现了盲信道估计。理论分析及仿真结果表明,所提方法与传统最小二乘方法相比,不仅提高了频带利用率而且具有更高的估计精度;与已有的二线性交替最小二乘方法(BALS)相比,所提算法有更快的收敛速度。 展开更多
关键词 大规模MIMO 盲信道估计 平行因子分解 约束交替最小二乘
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Reviving the stalled shock by jittering jets in core collapse supernovae: jets from the standing accretion shock instability
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作者 Noam Soker 《天文和天体物理学研究:英文版》 SCIE CAS CSCD 2019年第7期53-58,共6页
I present a scenario by which an accretion flow with alternating angular momentum on to a newly born neutron star in a core collapse supernova(CCSN) efficiently amplifies magnetic fields and by that launches jets.The ... I present a scenario by which an accretion flow with alternating angular momentum on to a newly born neutron star in a core collapse supernova(CCSN) efficiently amplifies magnetic fields and by that launches jets.The accretion flow of a collapsing core on to the newly born neutron star suffers spiral standing accretion shock instability(SASI).This instability leads to a stochastically variable angular momentum of the accreted gas,which in turn forms an accretion flow with alternating directions of the angular momentum,and hence alternating shear,at any given time.I study the shear in this alternating-shear sub-Keplerian inflow in published simulations,and present a new comparison with Keplerian accretion disks.From that comparison I argue that it might be as efficient as Keplerian accretion disks in amplifying magnetic fields by a dynamo.I suggest that although the average specific angular momentum of the accretion flow is small,namely,sub-Keplerian,this alternating-shear accretion flow can launch jets with varying directions,namely,jittering jets.Neutrino heating is an important ingredient in further energizing the jets.The jittering jets locally revive the stalled accretion shock in the momentarily polar directions,and by that they explode the star.I repeat again my call for a paradigm shift from a neutrino-driven explosion of CCSNe to a jet-driven explosion mechanism that is aided by neutrino heating. 展开更多
关键词 STARS jets-supernovae general-stars MASSIVE
Endoscopic management of massive rectal bleeding from a Dieulafoy's lesion: Case report 预览
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作者 Mario Rene Pineda-De Paz Massiel Madelin Rosario-Morel +2 位作者 Jose Guadalupe Lopez-Fuentes Luis Ariel Waller-Gonzalez Rodrigo Soto-Solis 《世界胃肠内镜杂志:英文版(电子版)》 2019年第7期438-442,共5页
BACKGROUND Rectal Dieulafoy's lesions (DLs) are very rare;however, they can be life threatening when presented with massive hemorrhage. CASE SUMMARY A 44-year-old female with medical history of chronic renal failu... BACKGROUND Rectal Dieulafoy's lesions (DLs) are very rare;however, they can be life threatening when presented with massive hemorrhage. CASE SUMMARY A 44-year-old female with medical history of chronic renal failure who was on renal replacement therapy presented with lower gastrointestinal hemorrhage. Physical examination revealed signs of hypovolemic shock and massive rectal bleeding. Complete blood count revealed abrupt decrease in hematocrit. After hemodynamic stabilization, an urgent colonoscopy was performed. A rectal DL was diagnosed, and it was successfully treated with two hemoclips. There were no signs of recurrent bleeding at thirty days of follow-up. CONCLUSION Rectal DLs represent an unusual cause of lower gastrointestinal bleeding. Massive hemorrhage can increase the morbidity and mortality of these patients. Endoscopic management continues to be the reference standard in the diagnosis and therapy of these lesions. Thermal, mechanical (hemoclip or band ligation), or combination therapy (adrenaline injection combined with thermal or mechanical therapy) should be considered the first choice for treatment. 展开更多
关键词 Dieulafoy's LESION Endoscopic HEMOSTASIS MASSIVE RECTAL BLEEDING Case report
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Probe Selection for Over-the-Air Test in 5G Base Stations with Massive Multiple-Input Multiple-Output 预览
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作者 Xiang Zhang Shangbin Qiao +1 位作者 Mugen Peng Yong Li 《中国通信:英文版》 SCIE CSCD 2019年第7期1-12,共12页
In 5G systems, massive multiple-input multiple-output (MIMO) has been adopted in base stations (BSs) to improve spectral efficiency and coverage. The traditional conductive performance test techniques are challenging ... In 5G systems, massive multiple-input multiple-output (MIMO) has been adopted in base stations (BSs) to improve spectral efficiency and coverage. The traditional conductive performance test techniques are challenging due to the unaffordable cost and high complexity when testing a large number of antennas. To solve this problem, the over-the-air (OTA) test has been presented, in which probe selection is the key to reduce the number of channel emulators and probes. In this paper, a novel artificial bee colony (ABC) algorithm is introduced to enhance the efficiency and accuracy of probe selection procedure. A sectoring- based multi-probe anechoic chamber (MPAC) is built to evaluate the throughput performance of massive MIMO equipped in 5G BS. In addition, link level simulation is carried out to evaluate the proposal’s performance gain under the commercial network assumptions, where the average throughput of three velocity is given with different SNR region. The results suggest that OTA chamber and multi-probe wall are available not only for 5G BSs, but also for user equipments (UEs) with end-to-end communication. 展开更多
关键词 anechoic chamber MASSIVE MIMO base stations over-the-air TEST PROBE SELECTION performance evaluation
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肺巨大炎性肌纤维母细胞瘤一例并文献复习
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作者 龙源 潘频华 +2 位作者 李园园 胡成平 李慧 《中国呼吸与危重监护杂志》 CAS CSCD 北大核心 2019年第3期254-258,共5页
目的分析肺巨大炎性肌纤维母细胞瘤(IMT)的临床症状、病理特征、诊断与鉴别诊断、治疗及预后,以提高该疾病的诊治水平。方法回顾性分析中南大学湘雅医院呼吸内科诊治的1例肺巨大IMT患者的临床资料,并通过知网、万方医学网和PubMed数据... 目的分析肺巨大炎性肌纤维母细胞瘤(IMT)的临床症状、病理特征、诊断与鉴别诊断、治疗及预后,以提高该疾病的诊治水平。方法回顾性分析中南大学湘雅医院呼吸内科诊治的1例肺巨大IMT患者的临床资料,并通过知网、万方医学网和PubMed数据库检索文献得到的病例报道的临床资料进行分析。结果患者为中年男性,以咳嗽、呼吸困难、消瘦为主要临床症状,影像学以一侧胸腔巨大占位为特点。经多次肺穿刺活检证实为肺巨大IMT。在数据库中共检索到8篇文献,其中英文文献6篇,中文文献2篇,加上本例,共9例患者。9例肺巨大IMT中,男4例,女5例,发病年龄1.5~75岁,平均年龄是28岁。临床症状无特异性,影像学均以一侧胸腔巨大占位为特点。1例发生全身远处转移(骨、肾上腺、淋巴结),1例发生术后远处转移(脑)。结论肺巨大IMT临床及影像学无特征性表现,明确诊断依赖于病理切片和免疫组织分析,临床上要和其他胸腔巨大肿瘤相鉴别。目前治疗方法首选手术切除。多数肺巨大IMT经手术完整切除预后较好。肺IMT的大小可能影响疾病预后。 展开更多
关键词 巨大 炎性肌纤维母细胞瘤 炎性假瘤
海量异构航行情报资料管理机制研究
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作者 荣晓慧 《民航学报》 2019年第3期66-67,113共3页
航行情报服务是保证现代民用航空安全运行的一个重要方面,航行情报搜集不全面、更新不及时等因素都会影响航空公司的运行安全。针对航空公司目前在管理航行资料时存在的问题,本文研究海量异构航行情报资料管理机制,统一管理世界范围内... 航行情报服务是保证现代民用航空安全运行的一个重要方面,航行情报搜集不全面、更新不及时等因素都会影响航空公司的运行安全。针对航空公司目前在管理航行资料时存在的问题,本文研究海量异构航行情报资料管理机制,统一管理世界范围内的航行情报信息,为航空公司航行情报人员提供一个完善的管理情报的工作平台,让航行资料的收集、处理和处理结果推送等工作形成一个闭环,有效地提升航空公司运行控制的管理能力和管理水平。 展开更多
关键词 海量 异构 航行情报资料管理 资料管理模型
Accretion onto Charged Black Holes in Einstein and Massive Theories of Gravity
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作者 Abdul Jawad Shahid Chaudhary 《理论物理通讯:英文版》 SCIE CAS CSCD 2019年第6期702-710,共9页
The accretion process is being investigated onto some important black holes such as Born-Infeld-AdS black hole, non-linear charged black hole solution in AdS space-time and Einstein-Yang-Mills massive gravity in the p... The accretion process is being investigated onto some important black holes such as Born-Infeld-AdS black hole, non-linear charged black hole solution in AdS space-time and Einstein-Yang-Mills massive gravity in the presence of Born-Infeld nonlinear electrodynamics. We find out the relations of radial velocity, energy density and change of mass for mention black holes and analyze their behavior graphically for different values of equation of state parameters ω.We also examine the relations for critical speed for these black holes. It is observed that for different state parameters different fluids exhibit different evolutions in black holes backgrounds. The energy density of some fluids is negative or positive near the black hole while other fluids become cause to increase or decrease in black hole mass. 展开更多
关键词 ACCRETION black holes EINSTEIN GRAVITY MASSIVE GRAVITY
Hybrid and Full-Digital Beamforming in mmWave Massive MIMO Systems:A Comparison Considering Low-Resolution ADCs 预览
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作者 Wence Zhang Xiaoxuan Xia +1 位作者 Yinkai Fu Xu Bao 《中国通信:英文版》 SCIE CSCD 2019年第6期91-102,共12页
In a millimeter-wave(mmWave)Massive multiple-input multiple-output(MIMO)systems,full-digital beamforming(i.e.,connecting each antenna with a specific radio-frequency(RF)chain)becomes inefficient due to the hardware co... In a millimeter-wave(mmWave)Massive multiple-input multiple-output(MIMO)systems,full-digital beamforming(i.e.,connecting each antenna with a specific radio-frequency(RF)chain)becomes inefficient due to the hardware cost and power consumption.Therefore,hybrid analog and digital transceiver where the number of RF chains are much smaller than that of the antennas has drawn great research interest.In this work,we investigate the use of low-resolution analog-to-digital converters(ADCs)in the uplink of multi-user hybrid and full-digital mmWave Massive MIMO systems.To be specific,we compare the performance of full-digital minimum mean square error(MMSE)and hybrid MMSE beamforming in both sum rates and energy efficiency.Accurate approximations of sum rates and energy efficiency are provided for both schemes,which captures the dominant factors.The analytical results show that full-digital beamforming outperforms hybrid beamforming in terms of sum rates and requires only a small portion(γ)of antennas used by hybrid beamforming to achieve the same sum rates.We given sufficient condition for full-digital beamforming to outperform hybrid beamforming in terms of energy efficiency.Moreover,an algorithm is proposed to search for the optimal ADC resolution bits.Numerical results demonstrate the correctness of the analysis. 展开更多
关键词 HYBRID MASSIVE MIMO mmWave MMSE low-resolution ADCS
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User Assisted Cooperative Relaying in Beamspace Massive MIMO NOMA Based Systems for Millimeter Wave Communications 预览
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作者 Jaipreet Kaur Maninder Lal Singh 《中国通信:英文版》 SCIE CSCD 2019年第6期103-113,共11页
A novel scheme‘user assisted cooperative relaying in beamspace massive multiple input multiple output(M-MIMO)non-orthogonal multiple access(NOMA)system’has been proposed to improve coverage area,spectrum and energy ... A novel scheme‘user assisted cooperative relaying in beamspace massive multiple input multiple output(M-MIMO)non-orthogonal multiple access(NOMA)system’has been proposed to improve coverage area,spectrum and energy efficiency for millimeter wave(mmWave)communications.A downlink system for M users,where base station(BS)is equipped with beamforming lens antenna structure having NRF radio frequency(RF)chains,has been considered.A dynamic cluster of users is formed within a beam and the intermediate users(in that cluster)between beam source and destination(user)act as relaying stations.By the use of successive interference cancellation(SIC)technique of NOMA within a cluster,the relaying stations relay the symbols with improved power to the destination.For maximizing achievable sum rate,transmit precoding and dynamic power allocation for both intra and inter beam power optimization are implemented.Simulations for performance evaluation are carried out to validate that the proposed system outperforms the conventional beamspace M-MIMO NOMA system for mmWave communications in terms of spectrum and energy efficiency. 展开更多
关键词 cooperative RELAYING system(CRS) millimeter wave(mmWave) MASSIVE MULTIPLE input MULTIPLE output(M-MIMO) non-orthogonal MULTIPLE access(NOMA) power allocation sum rate
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重症脑梗死优化诊治方案及流程建议草案
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作者 吴思缈 吴波 +11 位作者 郭富强 张世洪 郝子龙 杨东东 李小刚 吴碧华 王淳 段劲峰 凌天金 张浩 刘鸣 《华西医学》 2019年第10期1096-1108,共13页
重症/大面积脑梗死治疗难、预后差,定义不统一且针对性研究相对滞后。该草案推荐了相关定义标准和诊断流程,特别强调对重症/大面积脑梗死需重点关注恶性脑水肿预防和早期预测;加强监测意识和生命体征,及预防管理肺部感染等并发症;提出... 重症/大面积脑梗死治疗难、预后差,定义不统一且针对性研究相对滞后。该草案推荐了相关定义标准和诊断流程,特别强调对重症/大面积脑梗死需重点关注恶性脑水肿预防和早期预测;加强监测意识和生命体征,及预防管理肺部感染等并发症;提出了在重症患者中使用脑梗死特异性疗法(如静脉溶栓、血管内介入、抗血小板和抗凝治疗)的特殊建议;指出脑水肿和颅高压内外科治疗和早期康复在重症/大面积脑梗死患者的个体化应用需要更多研究。 展开更多
关键词 脑梗死 重症 大面积 诊治 流程
面向5G的高阶MIMO技术理论研究与应用分析
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作者 张庆 肖荣军 +2 位作者 施碧雄 金花 郭华 《江苏通信》 2019年第5期18-21,27共5页
随着移动通信技术的发展,新一代移动通信系统中需要更高的数据传输带宽、更快的传输速率,Massive MIMO凭借其高频谱利用率成为新一代移动通信系统中无线信号发射和接收的核心技术。本文介绍了MIMO的工作原理以及新一代移动通信系统MIMO... 随着移动通信技术的发展,新一代移动通信系统中需要更高的数据传输带宽、更快的传输速率,Massive MIMO凭借其高频谱利用率成为新一代移动通信系统中无线信号发射和接收的核心技术。本文介绍了MIMO的工作原理以及新一代移动通信系统MIMO优化算法,为MIMO技术及应用提供系统解决方案。 展开更多
关键词 MASSIVE MIMO 新一代移动通信 256QAM AFC
Save Biodiversity:A New Challenge for the World 预览
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作者 CAROLINA GARCIA 《今日中国:英文版》 2019年第11期14-15,共2页
IN 2020,the world community will meet in Beijing to discuss how to correct an almost irreversible problem–biodiversity loss at the Convention on Biological Diversity.Over the past half century,there has been a massiv... IN 2020,the world community will meet in Beijing to discuss how to correct an almost irreversible problem–biodiversity loss at the Convention on Biological Diversity.Over the past half century,there has been a massive decrease in the size of species populations worldwide.At the Beijing conference,China could play a decisive role in securing the planet’s future. 展开更多
关键词 PLANET IRREVERSIBLE MASSIVE
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Massive MIMO信号检测算法与仿真 预览
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作者 袁子蓝 《电子制作》 2019年第16期6-9,19共5页
为了应对当前蓬勃的通信网络需求和日益复杂的通信网络设计挑战,新型的通信技术层出不穷,其中Massive MIMO信号检测算法广泛应用到现代移动通信系统。本文以Massive MIMO信号检测算法为研究对象,通过对常见的信号检测算法的原理分析和... 为了应对当前蓬勃的通信网络需求和日益复杂的通信网络设计挑战,新型的通信技术层出不穷,其中Massive MIMO信号检测算法广泛应用到现代移动通信系统。本文以Massive MIMO信号检测算法为研究对象,通过对常见的信号检测算法的原理分析和公式推导,进而通过matlab实验仿真来比较各种算法的性能。本文通过对信号检测算法分析研究和仿真比较,对于理解相关算法研究提供奠定基础,为今后的工作提供一定帮助。 展开更多
关键词 MASSIVE MIMO 信号检测算法 MATLAB仿真
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Angular domain precoding-based PAPR reduction for massive MIMO systems
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作者 Ting LIU Luyao NI +1 位作者 Shi JIN Xiaohu YOU 《中国科学:信息科学(英文版)》 SCIE EI CSCD 2019年第10期220-222,共3页
Dear editor,Massive multiple-input multiple-output (MIMO)is a key technology of the fifth generation wireless communication systems (1, 2)Angle division multiple access (ADMA)[3] is one of the multiple access technolo... Dear editor,Massive multiple-input multiple-output (MIMO)is a key technology of the fifth generation wireless communication systems (1, 2)Angle division multiple access (ADMA)[3] is one of the multiple access technologies to explore the spatial degrees of freedom. It is based on the channel characteristic of each user in the angle domain, thereby the dimension of channel matrix is reduced due to the sparse distribution of users [4]. 展开更多
关键词 Angular DOMAIN precoding-based PAPR reduction for MASSIVE MIMO systems DOMAIN
Strength of massive to moderately jointed hard rock masses 预览
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作者 R.P.Bewick P.K.Kaiser F.Amann 《岩石力学与岩土工程学报:英文版》 CSCD 2019年第3期562-575,共14页
The Hoek-Brown (HB) failure criterion and the geological strength index (GSI) were developed for the estimation of rock mass strength in jointed and blocky ground where rock mass failure is dominated by sliding along ... The Hoek-Brown (HB) failure criterion and the geological strength index (GSI) were developed for the estimation of rock mass strength in jointed and blocky ground where rock mass failure is dominated by sliding along open joints and rotation of rock blocks. In massive, veined and moderately jointed rock in which rock blocks cannot form without failure of intact rock, the approach to obtain HB parameters must be modified. Typical situations when these modifications are required include the design of pillars, excavation and cavern stability, strainburst potential assessment, and tunnel support in deep underground conditions (around σ1/σci > 0.15, where σ1 is the major principal compressive stress and σci is the unconfined compressive strength of the homogeneous rock) in hard brittle rocks with GSI ≥ 65. In this article, the strength of massive to moderately jointed hard rock masses is investigated, and an approach is presented to estimate the rock mass strength envelope using laboratory data from uniaxial and triaxial compressive strength tests without reliance on the HB-GSI equations. The data from tests on specimens obtained from massive to moderately jointed heterogeneous (veined) rock masses are used to obtain the rock and rock mass strengths at confining stress ranges that are relevant for deep tunnelling and mining;and a methodology is presented for this purpose from laboratory data alone. By directly obtaining the equivalent HB rock mass strength envelope for massive to moderately jointed rock from laboratory tests, the HB-GSI rock mass strength estimation approach is complemented for conditions where the GSIequations are not applicable. Guidance is also provided on how to apply the proposed approach when laboratory test data are not or not yet available. 展开更多
关键词 BRITTLE ROCK Uniaxial compressive strength(UCS) Geological STRENGTH index(GSI) MASSIVE to moderately jointed ROCK MASSES
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广义赋形在5G天线设计中的应用 预览
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作者 丁文 刘木林 吴中林 《电信技术》 2019年第1期39-44,47共7页
5G无线网络一方面大量部署以Massive MIMO为代表的有源天线,另一方面无源基站天线通过多频带集成、FDD/TDD混合、扇区劈裂、增强MIMO等方式,保障基础覆盖,增加容量,改善用户体验。可以预见,这种由多元化基站天线组成的异构网络将比历史... 5G无线网络一方面大量部署以Massive MIMO为代表的有源天线,另一方面无源基站天线通过多频带集成、FDD/TDD混合、扇区劈裂、增强MIMO等方式,保障基础覆盖,增加容量,改善用户体验。可以预见,这种由多元化基站天线组成的异构网络将比历史上任何时期都要复杂,而且将长期存在。广义赋形技术不仅用于Massive MIM0和赋形天线的设计优化,在复杂异构天馈系统优化方面同样发挥着关键作用。文中从器件、阵列优化和MIMO部署三个维度对5G基站天线广义赋形技术进行介绍,展示该技术在5G通信中巨大的应用前景。 展开更多
关键词 5G天线 MASSIVE MIMO 基站天线设计 广义赋形技术
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微波消融联合肝动脉插管化疗栓塞术治疗巨块型肝癌的中期临床研究
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作者 鲍淼 袁洪胜 《中国临床研究》 CAS 2019年第10期1353-1356,1360共5页
目的探讨微波消融联合肝动脉插管化疗栓塞术(TACE)在巨块型肝癌中的应用价值。方法选取2014年10月至2016年8月收治的巨块型肝癌患者102例进行回顾性研究,采取TACE治疗的51例为对照组,采取TACE联合微波消融术治疗的51例为研究组。比较两... 目的探讨微波消融联合肝动脉插管化疗栓塞术(TACE)在巨块型肝癌中的应用价值。方法选取2014年10月至2016年8月收治的巨块型肝癌患者102例进行回顾性研究,采取TACE治疗的51例为对照组,采取TACE联合微波消融术治疗的51例为研究组。比较两组临床疗效、治疗前后血清癌胚抗原(CEA)、甲胎蛋白(AFP)水平、肝功能指标[天冬氨酸氨基转移酶(AST)、丙氨酸氨基转移酶(ALT)、总胆红素(TBIL)]水平。随访12~24个月,比较两组复发率,以直接计算法计算和比较两组12、18、24个月生存率。结果研究组肿瘤控制率(90.20%)高于对照组(74.51%,P<0.05)。两组治疗后血清AFP、CEA和AST、ATL、TBIL水平较治疗前降低,且研究组低于对照组(P均<0.01)。随访期间研究组失访1例,对照组失访2例,治疗后12个月研究组肝癌复发率(600%)与对照组(1633%)间无统计学差异(P>0.05);治疗后18个月及24个月研究组复发率(11.11%、19.51%)均低于对照组(29.29%、54.84%,P<0.05,P<0.01)。生存率直接计算法结果,治疗后12个月研究组生存率(90.00%)与对照组(83.67%)无统计学差异(P>0.05),治疗后18个月、24个月研究组生存率(86.00%、82.00%)高于对照组(69.39%、63.27%,P均<0.05)。结论采取TACE联合微波消融术治疗巨块型肝癌,可有效提高肿瘤控制率,降低血清肿瘤标志物水平,改善患者肝功能,提高生存率,降低复发风险。 展开更多
关键词 微波消融 肝动脉插管化疗栓塞术 肝癌 巨块型 肝功能 癌胚抗原 甲胎蛋白 复发率 生存率
16TR基站系统应用场景和产品形态的思考 预览 被引量:1
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作者 孙善球 刘旭 孙全有 《电信技术》 2019年第1期72-74,共3页
基于5G无线网建设面临的工程问题和挑战,研究5G网络组网的基站系统选型方案,提出“16TR是城区(高容量)主流配置,8TR是郊区和农村(中低容量)主流配置,64TR和32TR是超高容量的增强配置”。进一步从场景化工程需求、网络建设成本、性能可... 基于5G无线网建设面临的工程问题和挑战,研究5G网络组网的基站系统选型方案,提出“16TR是城区(高容量)主流配置,8TR是郊区和农村(中低容量)主流配置,64TR和32TR是超高容量的增强配置”。进一步从场景化工程需求、网络建设成本、性能可测试可评估等方面综合分析,发现16TR基站系统采用RRU和天线分离的方案相比A A U方案更具优势,是5G天线的重要发展方向,也是天线产业为5G无线网提供的高性价比解决方案。 展开更多
关键词 MASSIVE MIMO AAU 16TR RRU和天线分离
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Hybrid Precoding for mmWave Massive MIMO Systems with Different Antenna Arrays 预览
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作者 Qingfeng Ding Yuqian Deng +1 位作者 Xinpeng Gao Mengxia Liu 《中国通信:英文版》 SCIE CSCD 2019年第10期45-55,共11页
In this paper, the performance of hybrid precoding is investigated for mmWave massive MIMO systems with different antenna arrays. The hybrid precoding with partially connected architecture (PCA) is adopted. The spectr... In this paper, the performance of hybrid precoding is investigated for mmWave massive MIMO systems with different antenna arrays. The hybrid precoding with partially connected architecture (PCA) is adopted. The spectral efficiency (SE) and received energy efficiency (EE) are investigated by considering four types of antenna arrays, including uniform linear array (ULA), uniform rectangular planar array (URPA), uniform hexagonal planar array (UHPA), and uniform circular planar array (UCPA), respectively. We focus on analysis at the antenna response vector and utilize the idea of orthogonal matching pursuit algorithm to seek the optimal hybrid precoder. Furthermore, the trade-off of precoding architectures is studied between SE and received EE. Simulation results show that if the uniform planar array antenna is more concentrated, the SE and receive EE will be higher. Considering SE and received EE, the performance of planar arrays outperform linear array. There exist different optimal radio-frequency chain numbers to maximize the SE for planar array and linear array. In addition, the PCA can achieve relatively higher received EE while the SE is close to the fully connected architecture and the full digital architecture. 展开更多
关键词 MASSIVE MIMO mmWave HYBRID PRECODING array ANTENNA SPECTRAL efficiency
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