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Hemophagocytic lymphohistiocytosis with jaundice as first manifestation:A case report
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作者 Dan-Dan Wang sheng wu +1 位作者 Bing-Bing Kong Lin-Lin Song 《World Journal of Clinical Cases》 SCIE 2023年第34期8212-8218,共7页
BACKGROUND Hemophagocytic lymphohistiocytosis(HLH)is a rare but life-threatening condition.It is an immune-mediated disease that has a wide range of causes,elicits a hyperinflammatory response,and results in multiple ... BACKGROUND Hemophagocytic lymphohistiocytosis(HLH)is a rare but life-threatening condition.It is an immune-mediated disease that has a wide range of causes,elicits a hyperinflammatory response,and results in multiple organ damage.Clinical presentations vary,and in some cases,jaundice occurs as the first symptom.CASE SUMMARY We report the case of a 71-year-old female patient who presented with jaundice.She was admitted to our hospital because of the occurrence of“jaundice for half a month”,and upon examination,obstructive jaundice with choledocholithiasis and gallstones was suggested.Cholecystectomy and choledocholithotomy were performed.However,the jaundice did not improve after surgery.We found splenomegaly,cytopenia,hypertriglyceridemia,hypofibrinogenemia,and elevated ferritin.Bone marrow biopsy revealed hemophagocytosis.Later,cardiac arrest occurred when she returned 3 wk after the surgery.We considered that HLH was triggered by septic shock.The patient’s condition deteriorated rapidly,with multiple organ dysfunction and severe gastrointestinal bleeding.Corticosteroid therapy and symptomatic treatment failed to save her life.CONCLUSION Jaundice rarely presents as the first symptom in HLH patients.The HLH in this case was triggered by septic shock with jaundice as the first symptom.Clinicians should try hard to reduce missed diagnoses and misdiagnoses. 展开更多
关键词 Hemophagocytic lymphohistiocytosis JAUNDICE Common bile duct stones Bile duct obstruction Septic shock Case report
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大学生线上自主学习现状分析及能力培育策略研究 被引量:6
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作者 徐超毅 王向前 +1 位作者 盛武 牟勇 《宿州学院学报》 2021年第11期66-70,共5页
大学生线上自主学习能力是衡量新时代下大学生综合能力和素质的重要标准。为提高大学生的综合能力和素质,激发大学生的创新意识和创造能力,对大学生线上自主学习存在的问题和能力培育策略进行研究。通过设计问卷对5所高校的大学生进行... 大学生线上自主学习能力是衡量新时代下大学生综合能力和素质的重要标准。为提高大学生的综合能力和素质,激发大学生的创新意识和创造能力,对大学生线上自主学习存在的问题和能力培育策略进行研究。通过设计问卷对5所高校的大学生进行抽样调查,从学习者、教育者、线上平台和学习环境等方面进行探讨,分析目前大学生线上自主学习存在的主要问题,并有针对性地提出了解决问题的措施。相关措施的提出为科学培育大学生线上自主学习能力提供了一种思路和方向。 展开更多
关键词 大学生 线上 自主学习 能力培育
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基于CiteSpace的煤炭产能知识图谱构建与分析 被引量:2
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作者 盛武 张宁 《沈阳师范大学学报(自然科学版)》 CAS 2019年第5期434-439,共6页
随着供给侧改革的提出,煤炭产能问题逐渐成为国内能源经济领域研究的焦点问题之一。以CNKI为数据源,借助CiteSpace构建煤炭产能研究知识图谱,分析国内学术界关于煤炭产能的研究现状、研究热点、存在的问题及未来研究趋势。结果表明:目... 随着供给侧改革的提出,煤炭产能问题逐渐成为国内能源经济领域研究的焦点问题之一。以CNKI为数据源,借助CiteSpace构建煤炭产能研究知识图谱,分析国内学术界关于煤炭产能的研究现状、研究热点、存在的问题及未来研究趋势。结果表明:目前国内学术界关于煤炭产能年发文量较少,缺乏核心及以上高质量研究文献;研究人员基数较大,但高产作者比较匮乏,尚未形成跨学科、跨院校的作者合作关系;研究机构类型丰富,但机构间合作交流强度较弱,且地域分布不均衡现象较为突出;"供给侧改革""煤炭产能""转型升级"等是该领域研究的热点问题;近2年国内关于煤炭产能的研究有滞后倾向,未出现具有较高影响力的最新研究前沿。 展开更多
关键词 煤炭产能 知识图谱 供给侧 产能过剩 转型升级
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Deep Reinforcement Learning Based Joint Edge Resource Management in Maritime Network 被引量:11
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作者 Fangmin Xu Fan Yang +1 位作者 Chenglin Zhao sheng wu 《China Communications》 SCIE CSCD 2020年第5期211-222,共12页
Due to the rapid development of the maritime networks, there has been a growing demand for computation-intensive applications which have various energy consumption, transmission bandwidth and computing latency require... Due to the rapid development of the maritime networks, there has been a growing demand for computation-intensive applications which have various energy consumption, transmission bandwidth and computing latency requirements. Mobile edge computing(MEC) can efficiently minimize computational latency by offloading computation tasks by the terrestrial access network. In this work, we introduce a space-air-ground-sea integrated network architecture with edge and cloud computing components to provide flexible hybrid computing service for maritime service. In the integrated network, satellites and unmanned aerial vehicles(UAVs) provide the users with edge computing services and network access. Based on the architecture, the joint communication and computation resource allocation problem is modelled as a complex decision process, and a deep reinforcement learning based solution is designed to solve the complex optimization problem. Finally, numerical results verify that the proposed approach can improve the communication and computing efficiency greatly. 展开更多
关键词 maritime network edge computing computation offload computation latency reinforcement learning deep learning
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Low-Complexity Joint Channel Estimation and Symbol Detection for OFDMA Systems 被引量:4
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作者 Rui Xin Zuyao Ni +2 位作者 sheng wu Linling Kuang Chunxiao Jiang 《China Communications》 SCIE CSCD 2019年第7期49-60,共12页
In this paper,we propose a joint channel estimation and symbol detection(JCESD)algorithm relying on message-passing algorithms(MPA)for orthogonal frequency division multiple access(OFDMA)systems.The channel estimation... In this paper,we propose a joint channel estimation and symbol detection(JCESD)algorithm relying on message-passing algorithms(MPA)for orthogonal frequency division multiple access(OFDMA)systems.The channel estimation and symbol detection leverage the framework of expectation propagation(EP)and belief propagation(BP)with the aid of Gaussian approximation,respectively.Furthermore,to reduce the computation complexity involved in channel estimation,the matrix inversion is transformed into a series of diagonal matrix inversions through the Sherman-Morrison formula.Simulation experiments show that the proposed algorithm can reduce the pilot overhead by about 50%,compared with the traditional linear minimum mean square error(LMMSE)algorithm,and can approach to the bit error rate(BER)performance bound of perfectly known channel state information within 0.1 dB. 展开更多
关键词 JOINT channel estimation and SYMBOL detection MESSAGE PASSING OFDMA
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Weak harmonic signal detection method in chaotic interference based on extended Kalman filter 被引量:6
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作者 Chengye Lu sheng wu +1 位作者 Chunxiao Jiang Jinfeng Hu 《Digital Communications and Networks》 SCIE 2019年第1期51-55,共5页
The traditional methods of weak harmonic signal detection under strong chaotic interference often suffer from high computational complexity and poor performance. In this paper, an Extended Kalman Filter (EKF) based de... The traditional methods of weak harmonic signal detection under strong chaotic interference often suffer from high computational complexity and poor performance. In this paper, an Extended Kalman Filter (EKF) based detection method is proposed for the detection of weak harmonic signal. The EKF method avoids matrix inversion by iterating measurement equation and state equation, which simultaneously improves the robustness and reduces the complexity. Compared with the existing detection methods, the proposed method has the following advantages: 1) it has better performance than the neural network method;2) it has similar performance with the optimal filtering method, but with lower computational complexity;3) it is more robust compared with the optimal filtering method. 展开更多
关键词 Extended KALMAN filter STRONG CHAOTIC INTERFERENCE WEAK HARMONIC signal
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Effective genome editing and identification of a regiospecific gallic acid 4-O-glycosyltransferase in pomegranate(Punica granatum L.) 被引量:8
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作者 Lijing Chang sheng wu Li Tian 《Horticulture Research》 SCIE 2019年第1期206-220,共15页
Pomegranate(Punica granatum L.)trees are woody perennials that bear colorful and nutritious fruits rich in phenolic metabolites,e.g.,hydrolyzable tannins(HTs)and flavonoids.We here report genome editing and gene disco... Pomegranate(Punica granatum L.)trees are woody perennials that bear colorful and nutritious fruits rich in phenolic metabolites,e.g.,hydrolyzable tannins(HTs)and flavonoids.We here report genome editing and gene discovery in pomegranate hairy roots using Clustered Regularly Interspaced Short Palindromic Repeats(CRISPR)/CRISPR-associated protein 9(Cas9)(CRISPR/Cas9),coupled with transcriptome and biochemical analyses.Single guide RNAs(sgRNAs)were designed to target two UDP-dependent glycosyltransferases(UGTs),PgUGT84A23 and PgUGT84A24,which possess overlapping activities inβ-glucogallin(a galloylglucose ester;biosynthetic precursor of HTs)biosynthesis.A unique accumulation of gallic acid 3-O-and 4-O-glucosides(galloylglucose ethers)was observed in the PgUGT84A23 and PgUGT84A24 dual CRISPR/Cas9-edited lines(i.e.,ugt84a23 ugt84a24)but not the control(empty vector)or PgUGT84A23/PgUGT84A24 single edited lines(ugt84a23 or ugt84a24).Transcriptome and real-time qPCR analyses identified 11 UGTs with increased expression in the ugt84a23 ugt84a24 hairy roots compared to the controls.Of the 11 candidate UGTs,only PgUGT72BD1 used gallic acid as substrate and produced a regiospecific product gallic acid 4-O-glucoside.This work demonstrates that the CRISPR/Cas9 method can facilitate functional genomics studies in pomegranate and shows promise for capitalizing on the metabolic potential of pomegranate for germplasm improvement. 展开更多
关键词 ROOTS specific PHENOLIC
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A PSO Based Multi-Domain Virtual Network Embedding Approach 被引量:3
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作者 Yongjing Ni Guoyan Huang +3 位作者 sheng wu Chenxi Li Peiying Zhang Haipeng Yao 《China Communications》 SCIE CSCD 2019年第4期105-119,共15页
This paper proposed a multi-domain virtual network embedding algorithm based on multi-controller SDN architecture. The local controller first selects candidate substrate nodes for each virtual node in the domain. Then... This paper proposed a multi-domain virtual network embedding algorithm based on multi-controller SDN architecture. The local controller first selects candidate substrate nodes for each virtual node in the domain. Then the global controller abstracts substrate network topology based on the candidate nodes and boundary nodes of each domain, and applies Particle Swarm Optimization Algorithm on it to divide virtual network requests. Each local controller then embeds the virtual nodes of the divided single-domain virtual network requests in the domain, and cooperates with other local controllers to embed the inter-domain virtual links. Simulation experimental results show that the proposed algorithm has good performance in reducing embedding cost with good stability and scalability. 展开更多
关键词 MULTI-DOMAIN VIRTUAL NETWORK embedding CANDIDATE node particle SWARM optimization algorithm VIRTUAL NETWORK REQUEST division
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Klebsiella pneumoniae infection secondary to spontaneous renal rupture that presents only as fever:A case report 被引量:3
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作者 Chen-Guang Zhang Min Duan +5 位作者 Xiang-Yang Zhang Yan Wang sheng wu Li-Li Feng Lin-Lin Song Xu-Yan Chen 《World Journal of Clinical Cases》 SCIE 2021年第11期2602-2610,共9页
BACKGROUND Spontaneous renal rupture is a rare disease in the clinic.The causes of spontaneous renal rupture include extrarenal factors,intrarenal factors,and idiopathic factors.Reports on infection secondary to spont... BACKGROUND Spontaneous renal rupture is a rare disease in the clinic.The causes of spontaneous renal rupture include extrarenal factors,intrarenal factors,and idiopathic factors.Reports on infection secondary to spontaneous renal rupture and the complications of spontaneous renal rupture are scarce.Furthermore,there are few patients with spontaneous renal rupture who present only with fever.CASE SUMMARY We present the case of a 52-year-old female patient who was admitted to our hospital.She presented only with fever,and the cause of the disease was unclear.She underwent a contrast-enhanced computed tomography(CT)scan,which showed that the left renal capsule had a crescent-shaped,low-density shadow;the perirenal fat was blurred,and exudation was visible with no sign of calculi,malignancies,instrumentation,or trauma.Under ultrasound guidance,a pigtail catheter was inserted into the hematoma,and fluid was drained and used for the bacterial test,which proved the presence of Klebsiella pneumoniae.Two months later,abdominal CT showed that the hematoma was absorbed,so the drainage tube was removed.The abdominal CT was normal after 4 mo.CONCLUSION Spontaneous renal rupture due to intrarenal factors causes a higher proportion of shock and is more likely to cause anemia. 展开更多
关键词 SPONTANEOUS Renal rupture Klebsiella pneumoniae FEVER INFECTION Case report
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Impact of the green credit policy on external financing,economic growth and energy consumption of the manufacturing industry 被引量:3
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作者 sheng wu Liangpeng wu Xianglian Zhao 《Chinese Journal of Population,Resources and Environment》 2022年第1期59-68,共10页
China attempts to achieve energy conservation,emission reduction and environmental protection through the implementation of the green credit policy,but its implementation impact is still controversial.An important con... China attempts to achieve energy conservation,emission reduction and environmental protection through the implementation of the green credit policy,but its implementation impact is still controversial.An important content of the green credit policy is to require banking and financial institutions to tighten the credit exposure of industries of‘high pollution and high energy consumption’and industries with overcapacity,so as to use economic leverage to curb their blind expansion and reduce energy consumption by controlling external financing.This paper examined the impact and the lingering effects of the green credit policy on external financing,economic growth and energy consumption in the manufacturing industry,which was most influenced by the green credit policy,from 2003 to 2016 by using the DID method.Furthermore,this paper estimated the dynamic endogenous relationships among external financing,economic growth and energy consumption with two-step system GMM model to investigate the influential path of the green credit policy.The results showed that:the green credit policy had a significant negative impact on the external financing of manufacturing industry,but its negative impact on the economic growth and energy consumption of manufacturing industry was not statistically significant,and the effect of the green credit policy had a dynamic feature of weakening with time.Additionally,in the manufacturing industry,there was a bilateral causal relationship between the energy consumption and economic growth of the control group industry and the processing group industry.There was a bilateral causal relationship between the economic growth and external financing of the control group industries in the manufacturing industry.There was a unilateral causal relationship between the economic growth and external financing of the processing group industries in the manufacturing industry,while the external causality existed between the control group industries and the processing group industries in the manufacturing industry.The causal relationship between the financing and energy consumption was not statistically significant.At present,the transmission path of the green credit policy is that the green credit policy controls external financing,then affects economic growth and ultimately inhibits energy consumption,but the effectiveness of the path is not statistically significant.The conclusion of this paper provides policy reference and scientific basis for the adjustment and improvement of green credit. 展开更多
关键词 Green credit Energy consumption DIFFERENCE-IN-DIFFERENCES Manufacturing industry
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Topology Based Reliable Virtual Network Embedding from a QoE Perspective 被引量:2
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作者 Peiying Zhang sheng wu +2 位作者 Miao Wang Haipeng Yao Yunjie Liu 《China Communications》 SCIE CSCD 2018年第10期38-50,共13页
In the network virtualization environments, one of the most challenges is how to map the virtual networks(VNs) onto a shared substrate network managed by an infrastructure provider(In P), which is termed as virtual ne... In the network virtualization environments, one of the most challenges is how to map the virtual networks(VNs) onto a shared substrate network managed by an infrastructure provider(In P), which is termed as virtual network embedding problem. Prior studies on this issue only emphasize on maximizing the revenue or minimizing the energy consumption while ignoring the reliability requirements of end-users. In our work, we incorporate the reliability probability into the virtual network embedding process with an aim to improve the Qo S/Qo E of end users from a new perspective. We devised two novel reliable virtual network embedding algorithms called RRW-Max Match and RDCC-VNE based on RW-Max Match and DCC-VNE, respectively. Extensive simulations demonstrated that the efficiency of our proposed algorithms is better than those of two primitive algorithms in terms of the reliability demands, the acceptance ratio of virtual networks and the long-term average revenue. 展开更多
关键词 虚拟网络 嵌入问题 拓扑学 可靠性要求 供应商管理 可靠性概率 基础结构 最终用户
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In-situ SiN combined with etch-stop barrier structure for high-frequency AlGaN/GaN HEMT 被引量:1
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作者 宓珉瀚 武盛 +6 位作者 杨凌 何云龙 侯斌 张濛 郭立新 马晓华 郝跃 《Chinese Physics B》 SCIE EI CAS CSCD 2020年第4期430-433,共4页
The etch-stop structure including the in-situ SiN and AlGaN/GaN barrier is proposed for high frequency applications.The etch-stop process is realized by placing an in-situ SiN layer on the top of the thin AlGaN barrie... The etch-stop structure including the in-situ SiN and AlGaN/GaN barrier is proposed for high frequency applications.The etch-stop process is realized by placing an in-situ SiN layer on the top of the thin AlGaN barrier.F-based etching can be self-terminated after removing SiN,leaving the AlGaN barrier in the gate region.With this in-situ SiN and thin barrier etch-stop structure,the short channel effect can be suppressed,meanwhile achieving highly precisely controlled and low damage etching process.The device shows a maximum drain current of 1022 mA/mm,a peak transconductance of 459 mS/mm,and a maximum oscillation frequency(fmax)of 248 GHz. 展开更多
关键词 AlGaN/GaN IN-SITU SIN etch-stop barrier
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Efficient Recovery of Structured Sparse Signals via Approximate Message Passing with Structured Spike and Slab Prior 被引量:1
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作者 Xiangming Meng sheng wu +2 位作者 Michael Riis ANDersen Jiang Zhu Zuyao Ni 《China Communications》 SCIE CSCD 2018年第6期1-17,共17页
Due to limited volume, weight and power consumption, micro-satellite has to reduce data transmission and storage capacity by image compression when performs earth observation missions. However, the quality of images m... Due to limited volume, weight and power consumption, micro-satellite has to reduce data transmission and storage capacity by image compression when performs earth observation missions. However, the quality of images may be unsatisfied. This paper considers the problem of recovering sparse signals by exploiting their unknown sparsity pattern. To model structured sparsity, the prior correlation of the support is encoded by imposing a transformed Gaussian process on the spike and slab probabilities. Then, an efficient approximate message-passing algorithm with structured spike and slab prior is derived for posterior inference, which, combined with a fast direct method, reduces the computational complexity significantly. Further, a unified scheme is developed to learn the hyperparameters using expectation maximization(EM) and Bethe free energy optimization. Simulation results on both synthetic and real data demonstrate the superiority of the proposed algorithm. 展开更多
关键词 结构化 平板 信号 消息 GAUSSIAN 计算复杂性 期望最大化
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Speech Enhancement Based on Approximate Message Passing 被引量:1
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作者 Chao Li Ting Jiang sheng wu 《China Communications》 SCIE CSCD 2020年第8期187-198,共12页
To overcome the limitations of conventional speech enhancement methods, such as inaccurate voice activity detector(VAD) and noise estimation, a novel speech enhancement algorithm based on the approximate message passi... To overcome the limitations of conventional speech enhancement methods, such as inaccurate voice activity detector(VAD) and noise estimation, a novel speech enhancement algorithm based on the approximate message passing(AMP) is adopted. AMP exploits the difference between speech and noise sparsity to remove or mute the noise from the corrupted speech. The AMP algorithm is adopted to reconstruct the clean speech efficiently for speech enhancement. More specifically, the prior probability distribution of speech sparsity coefficient is characterized by Gaussian-model, and the hyper-parameters of the prior model are excellently learned by expectation maximization(EM) algorithm. We utilize the k-nearest neighbor(k-NN) algorithm to learn the sparsity with the fact that the speech coefficients between adjacent frames are correlated. In addition, computational simulations are used to validate the proposed algorithm, which achieves better speech enhancement performance than other four baseline methods-Wiener filtering, subspace pursuit(SP), distributed sparsity adaptive matching pursuit(DSAMP), and expectation-maximization Gaussian-model approximate message passing(EM-GAMP) under different compression ratios and a wide range of signal to noise ratios(SNRs). 展开更多
关键词 speech enhancement approximate message passing Gaussian model expectation maximization algorithm
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High performance InAlN/GaN high electron mobility transistors for low voltage applications 被引量:1
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作者 宓珉瀚 张濛 +6 位作者 武盛 杨凌 侯斌 周雨威 郭立新 马晓华 郝跃 《Chinese Physics B》 SCIE EI CAS CSCD 2020年第5期469-472,共4页
A high performance InAlN/GaN high electron mobility transistor(HEMT)at low voltage operation(6-10 V drain voltage)has been fabricated.An 8 nm InAlN barrier layer is adopted to generate large 2DEG density thus to reduc... A high performance InAlN/GaN high electron mobility transistor(HEMT)at low voltage operation(6-10 V drain voltage)has been fabricated.An 8 nm InAlN barrier layer is adopted to generate large 2DEG density thus to reduce sheet resistance.Highly scaled lateral dimension(1.2μm source-drain spacing)is to reduce access resistance.Both low sheet resistance of the InAlN/GaN structure and scaled lateral dimension contribute to an high extrinsic transconductance of 550 mS/mm and a large drain current of 2.3 A/mm with low on-resistance(Ron)of 0.9Ω·mm.Small signal measurement shows an fT/fmax of 131 GHz/196 GHz.Large signal measurement shows that the InAlN/GaN HEMT can yield 64.7%-52.7%(Vds=6-10 V)power added efficiency(PAE)associated with 1.6-2.4 W/mm output power density at 8 GHz.These results demonstrate that GaN-based HEMTs not only have advantages in the existing high voltage power and high frequency rf field,but also are attractive for low voltage mobile compatible rf applications. 展开更多
关键词 InAlN/GaN high electron mobility transistor(HEMT) low voltage
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Minimum Amount of Extracting Solvent of a Separation of Two Rare Earth Components 被引量:1
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作者 Fuxiang Cheng sheng wu +4 位作者 Yan Liu Songling Wang Bo Zhang Chunsheng Liao Chunhua Yan 《Advances in Materials Physics and Chemistry》 2014年第12期275-283,共9页
A significant development in the theory of countercurrent extraction will be presented in this article. New expressions of the term in countercurrent extraction process analysis, “Adjacent Stage Impurity Ratio” (ASI... A significant development in the theory of countercurrent extraction will be presented in this article. New expressions of the term in countercurrent extraction process analysis, “Adjacent Stage Impurity Ratio” (ASIR), are deduced. Furthermore, based on the term together with mass balance and extraction equilibrium, the conditions where a given countercurrent extraction separation operation can have minimum amounts of both extracting solvent and scrubbing agent solution can be estimated, and the equations of the two minimum amounts can be deduced. It was found that the equations for a two-component separation using a single aqueous or organic feed are exactly the same as they appeared in the theory initially established in 1970s. Unlike its earlier version, the present derivation does not involve feed-stage-composition hypothesis, and also has the advantage of dealing with a double-feed system where both aqueous and organic feeds are simultaneously employed whereas the earlier theory can only analyze a separation using a single aqueous or organic feed. 展开更多
关键词 Theory of Countercurrent Extraction Minimum AMOUNT of EXTRACTING SOLVENT TWO-COMPONENT SEPARATION Adjacent Stage IMPURITY Ratio
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Numerical modeling of solute transport in deformable unsaturated layered soil
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作者 sheng wu Dong-sheng Jeng 《Water Science and Engineering》 EI CAS CSCD 2017年第3期184-196,共13页
The effect of soil stratification was studied through numerical investigation based on the coupled model of solute transport in deformable unsaturated soil. The theoretical model implied two-way coupled excess pore pr... The effect of soil stratification was studied through numerical investigation based on the coupled model of solute transport in deformable unsaturated soil. The theoretical model implied two-way coupled excess pore pressure and soil deformation based on Biot's consolidation theory as well as a one-way coupled volatile pollutant concentration field developed from the advection-diffusion theory. Embedded in the model, the degree of saturation, fluid compressibility, self-weight of the soil matrix, porosity variance, longitudinal dispersion, and linear sorption were computed. Based on simulation results of a proposed three-layer landfill model using the finite element method, the multi-layer effects are discussed with regard to the hydraulic conductivity, shear modulus, degree of saturation, molecular diffusion coefficient, and thickness of each layer. Generally speaking, contaminants spread faster in a stratified field with a soft and highly permeable top layer; soil parameters of the top layer are more critical than the lower layers but controlling soil thicknesses will alter the results. This numerical investigation showed noticeable impacts of stratified soil properties on solute migration results, demonstrating the importance of correctly modeling layered soil instead of simply assuming the averaged properties across the soil profile. 展开更多
关键词 SOLUTE transport LAYERED SOIL CONSOLIDATION UNSATURATED SOIL Deformable media
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High-frequency enhancement-mode millimeterwave AlGaN/GaN HEMT with an fT/fmax over 100 GHz/200 GHz
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作者 武盛 宓珉瀚 +3 位作者 马晓华 杨凌 侯斌 郝跃 《Chinese Physics B》 SCIE EI CAS CSCD 2021年第8期444-448,共5页
Ultra-thin barrier(UTB) 4-nm-Al Ga N/Ga N normally-off high electron mobility transistors(HEMTs) having a high current gain cut-off frequency( fT) are demonstrated by the stress-engineered compressive Si N trench tech... Ultra-thin barrier(UTB) 4-nm-Al Ga N/Ga N normally-off high electron mobility transistors(HEMTs) having a high current gain cut-off frequency( fT) are demonstrated by the stress-engineered compressive Si N trench technology.The compressive in-situ Si N guarantees the UTB-Al Ga N/Ga N heterostructure can operate a high electron density of1.27×1013 cm-2, a high uniform sheet resistance of 312.8 Ω/, but a negative threshold for the short-gate devices fabricated on it. With the lateral stress-engineering by full removing in-situ Si N in the 600-nm Si N trench, the short-gated(70 nm) devices obtain a threshold of 0.2 V, achieving the devices operating at enhancement-mode(E-mode). Meanwhile,the novel device also can operate a large current of 610 m A/mm and a high transconductance of 394 m S/mm for the Emode devices. Most of all, a high fT/fmax of 128 GHz/255 GHz is obtained, which is the highest value among the reported E-mode Al Ga N/Ga N HEMTs. Besides, being together with the 211 GHz/346 GHz of fT/fmax for the D-mode HEMTs fabricated on the same materials, this design of E/D-mode with the realization of fmax over 200 GHz in this work is the first one that can be used in Q-band mixed-signal application with further optimization. And the minimized processing difference between the E-and D-mode designs the addition of the Si N trench, will promise an enormous competitive advantage in the fabricating costs. 展开更多
关键词 ultra-thin barrier(UTB) AlGaN/GaN in-situ SiN stress-engineering ENHANCEMENT-MODE mixed-signal applications
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BER Performance Analysis of Asynchronous NOMA with Arbitrary Phase Offset
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作者 Chang Liu sheng wu +1 位作者 Chunxiao Jiang Hongwen Yang 《China Communications》 SCIE CSCD 2022年第11期195-208,共14页
An asynchronous transmission scenario for non-orthogonal multiple access(NOMA)user signals with arbitrary phase offset is investigated in this paper.To improve the system performance in the user power-balanced conditi... An asynchronous transmission scenario for non-orthogonal multiple access(NOMA)user signals with arbitrary phase offset is investigated in this paper.To improve the system performance in the user power-balanced conditions,we adopt a synthetic detection method at the receiver,i.e.,the jointly optimal maximal likelihood detection aided triangular successive interference cancellation(JO ML-TSIC)method.Analytical bit error rate(BER)solutions are obtained for a two-user case with the optimal,intentional onehalf symbol period time delay implemented between the user signals.Furthermore,closed-form BER solutions for the case using the triangular successive interference cancellation(TSIC)detection method are also derived for comparisons.Numerical results show that the JO ML-TSIC receiver for the asynchronous system outperforms the TSIC receiver as well as the synchronous successive interference cancellation(SIC)receiver in all the conditions concerned.The results also show that the superiority of the JO ML-TSIC receiver is strengthened when the signals experience flat Rayleigh fading channels compared to the TSIC and the synchronous SIC receivers. 展开更多
关键词 non-orthogonal multiple access(NOMA) asynchronous transmission jointly optimal(JO)maximum likelihood(ML)detection successive interference cancellation(SIC) bit error rate(BER)
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Trap analysis of composite 2D-3D channel in AlGaN/GaN/graded-AlGaN:Si/GaN:C multi-heterostructure at different temperatures
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作者 胡晟 杨凌 +12 位作者 宓珉瀚 侯斌 刘晟 张濛 武玫 朱青 武盛 卢阳 祝杰杰 周小伟 吕玲 马晓华 郝跃 《Chinese Physics B》 SCIE EI CAS CSCD 2020年第8期451-456,共6页
The graded AlGaN:Si back barrier can form the majority of three-dimensional electron gases(3DEGs)at the GaN/graded AlGaN:Si heterostructure and create a composite two-dimensional(2D)-three-dimensional(3D)channel in Al... The graded AlGaN:Si back barrier can form the majority of three-dimensional electron gases(3DEGs)at the GaN/graded AlGaN:Si heterostructure and create a composite two-dimensional(2D)-three-dimensional(3D)channel in AlGaN/GaN/graded-AlGaN:Si/GaN:C heterostructure(DH:Si/C).Frequency-dependent capacitances and conductance are measured to investigate the characteristics of the multi-temperature trap states of in DH:Si/C and AlGaN/GaN/GaN:C heterostructure(SH:C).There are fast,medium,and slow trap states in DH:Si/C,while only medium trap states exist in SH:C.The time constant/trap density for medium trap state in SH:C heterostructure are(11μs-17.7μs)/(1.1×10^13 cm^-2·eV^-1-3.9×10^13 cm^-2·eV^-1)and(8.7μs-14.1μs)/(0.7×10^13 cm^-2·eV^-1-1.9×10^13 cm^-2·eV^-1)at 300 K and 500 K respectively.The time constant/trap density for fast,medium,and slow trap states in DH:Si/C heterostructure are(4.2μs-7.7μs)/(1.5×10^13 cm^-2·eV^-1-3.2×10^13 cm^-2·eV^-1),(6.8μs-11.8μs)/(0.8×10^13 cm^-2·eV^-1-2.8×10^13 cm^-2·eV^-1),(30.1μs-151μs)/(7.5×10^12 cm^-2·eV^-1-7.8×10^12 cm^-2·eV^-1)at 300 K and(3.5μs-6.5μs)/(0.9×10^13 cm^-2·eV^-1-1.8×10^13 cm^-2·eV^-1),(4.9μs-9.4μs)/(0.6×10^13 cm^-2·eV^-1-1.7×10^13 cm^-2·eV^-1),(20.6μs-61.9μs)/(3.2×10^12 cm^-2·eV^-1-3.5×10^12 cm^-2·eV^-1)at 500 K,respectively.The DH:Si/C structure can effectively reduce the density of medium trap states compared with SH:C structure. 展开更多
关键词 AlGaN/GaN HEMT multi-heterostructure composite 2D-3D channel multi-temperature trap states
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