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Resource scheduling scheme with QoS support in two-hop relay-enhanced OFDMA systems

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The Journal of China Universities of Posts and Telecommunications 2010年第4期17卷 26-30页

作者： liu wei ,ji Hong,LI Ting School of Information and Telecommunication Engineering,Beijing University of Posts and Telecommunications,Beijing 100876,China School of Information and Telecommunication Engineering Beijing University of Posts and Telecommunications Beijing 100876 China

As the system performance is obviously improved by introducing the concept of relay into the traditional orthogonal frequency division multiple access （OFDMA） systems, resource scheduling in relay-enhanced OFDMA systems is worthy of being studied carefully. To solve the optimization problem of achieving the maximum throughput while satisfying the quality of service （QoS） and guaranteeing the fairness of users, a novel resource scheduling scheme with QoS support for the downlink of two-hop relay-enhanced OFDMA systems is proposed. The proposed scheme, which is considered both in the first time sub-slot between direct link users and relay stations, and the second time sub-slot among relay link users, takes QoS support into consideration, as well as the system throughput and the fairness for users. Simulation results show that the proposed scheme has good performance in maximizing system throughput and guaranteeing the performance in the service delay and the data loss rate.

关键词： relay OFDMA QoS resource scheduling

2,2′-二硫代二苯甲酸、2,2′-二羧苯基硫醚及氮杂环配体的锌和钴配合物的合成、晶体结构与性质（英文）

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无机化学学报 2017年第4期33卷 705-712页

作者：刘继伟东北石油大学化学化工学院黑龙江省石油与天然气重点实验室大庆163318

使用2,2′-二硫代二苯甲酸和1H-咪唑[4,5-f][1,10]菲咯啉(ip)、硝酸锌在水热条件下发生的原位反应合成了1个锌配合物,即[Zn(C_(14)H_8O_4S)(ip)(H_2O)](1)(C_(14)H_8O_4S=2,2′-二羧苯基硫醚);然后又利用2,2′-二硫代二苯甲酸和咪唑(im)、硝酸钴在水溶液中合成了1个钴配合物,即{[Co(C_(14)H_8O_4S_2)(im)_2]·H_2O}n(2)(C_(14)H_8O_4S_2=2,2′-二硫代二苯甲酸根),并对它们分别进行了元素分析、红外光谱、热稳定性、荧光光谱、X射线粉末衍射和X射线单晶衍射的表征。结果表明:配合物1由2,2′-二羧苯基硫醚配体连接形成了一个双核的化合物,且锌原子是五配位的三角双锥结构。配合物2由二硫代二苯甲酸配体桥联形成了一个一维链状结构,且钴原子是六配位的八面体结构。

关键词： 2,2′-二硫代二苯甲酸 2,2′-二羧苯基硫醚原位反应晶体结构

Enhancement-Mode InAlAs/InGaAs/InP High Electron Mobility Transistor with Strained InAlAs Barrier Layer

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Chinese Physics Letters 2000年第8期17卷 619-620页

作者： AO jin-Ping ZENG Qing-Ming ZHAO Yong-Lin LI Xian-jie liu wei-ji liu Shi-Yong LIANG Chun-guang Hebei Semiconductor Research Institute Shijiazhuang 050051 National Integrated Optoelectronics Laboratory Jilin UniversityChangchun 130023

The relatively low Schottky barrier height on In_(0.52)Al_(0.48)As lattice-matched to InP has hampered the achievement of enhancement-mode InA1As/InGaAs/InP high electron mobility transistors(E-HEMTs).By introducing lattice mismatched strained aluminum-rich In_(0.45) Al_(0.55)As as the Schottky contact material to enhance the barrier height,we have developed InP-based InAlAs/InGaAs/InP E-HEMT with threshold voltage of about 150 m V.A maximum extrinsic transconductance of 660mS/mm and output conductance of 15mS/mm are measured for 1μm-gate length devices at room *** devices also show excellent radio-frequency performance with cutoff frequency of 50 GHz and maximum oscillation frequency of 54 GHz.

关键词： temperature. Schottky HEMTs

Combined en bloc liver/pancreas transplantation in two different patients

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World Journal of Gastroenterology 2009年第20期15卷 2552-2555页

作者： Zhi-Shui Chen Fan-Ying Meng Xiao-Ping Chen Dun-Gui liu Lai wei ji-Pin jiang Dun-Feng Du wei-jie Zhang Chang-Sheng Ming Nian-Qiao Gong Institute of Organ Transplantation Tongji Hospital Tongji Medical College Huazhong University of Science and Technology Wuhan 430030 Hubci Province China

Combined en bloc liver/pancreas transplantation （CLPT） was used primarily in the treal^nent of otherwise non- resectable upper abdominal malignancy. In fact, a more appropriate indication is in patients with liver disease and insulin-dependent diabetes mellitus （IDDM）. Here, we report on two successful cases of CLPT at our hospital. One was a patient with non-resectable advanced liver cancer. The recipient survived for 23 mo and finally died of recurrent tumor. The other was a patient with severe biliary complication after orthotopic liver transplantation and preoperative IDDM. We performed CLPT with a modified surgical technique of preserving the native pancreas. He is currently liver-disease- and insulin-free more than 27 mo post-transplant. Based on our experience in two cases of abdominal cluster transplantation, we describe the technical details of CLPT and a modification of the surgical procedure.

关键词： Transplantation Liver Pancreas Diabetes mellitus Liver cancer

Field Effect Transistor with Self-Organized In_(0.15)Ga_(0.85)As/GaAs Quantum Wires as a Channel Grown on (553)B GaAs Substrates

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Chinese Physics Letters 2001年第8期18卷 1147-1149页

作者： LI Xian-jie YAN Fa-Wang ZHANG Wen-Jun ZHANG Rong-Gui liu wei-ji AO jin-Ping ZENG Qing-Ming liu Shi-Yong LIANG Chun-Guang Hebei Semiconductor Research Institute Shijiazhuang 050051 Department of Electronic Engineering Jilin UniversityChangchun 130023 Department of Electrical and Electronic Engineering Tokushima UniversityTokushima 770-8506Japan

A functional field effect transistor with self-organized In_(0.15)Ga_(0.85)As/GaAs quantum wires(QWRs)as a channel was achieved by molecular beam epitaxy on a(553)B GaAs *** the three-dimensional image of atom force microscopy and the polarization of the photoluminance peaks reveal that the channel of the device is a self-organized QWR *** device with a gate-length of 2μm and a source-drain spacing of 5μm performed a good enhancement-mode characteristic and a maximum transconductance of 65 mS/mm was obtained at the gate voltage of 1.0 V by the geometric gate-width at room *** saturated drain current is as high as 5.6 *** device exhibited a much larger current capacity due to the high density of the self-organized QWRs in its channel *** addition,the effective gate width was discussed in comparison with the geometric gate width of the device,from which a larger maximum transconductance of 130 mS/mm could be estimated.

关键词： drain channel polarization

不同锻造比对2A50铝合金组织和性能的影响

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轻合金加工技术 2014年第11期42卷 54-58页

作者：刘记伟东北轻合金有限责任公司黑龙江哈尔滨150060

影响铝合金自由锻件组织和性能的因素很多,铸锭质量、锻造变形程度和热处理工艺影响最大。通过对2A50铝合金不同锻造工艺对性能产生的影响进行研究,采用不同的锻造方案(镦粗、多方锻、拔长等)和不同的锻造比生产的锻件进行性能分析,阐... 详细信息

影响铝合金自由锻件组织和性能的因素很多,铸锭质量、锻造变形程度和热处理工艺影响最大。通过对2A50铝合金不同锻造工艺对性能产生的影响进行研究,采用不同的锻造方案(镦粗、多方锻、拔长等)和不同的锻造比生产的锻件进行性能分析,阐明了自由锻造工艺对锻件性能的影响。

关键词： 2A50铝合金锻造比镦粗拔长

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鲁棒多模型自适应控制系统的稳定性

自动化学报 2015年第1期41卷 113-121页

作者：张维存刘冀伟胡广大北京科技大学自动化学院北京100083

研究含有不确定性的连续时间随机被控对象的鲁棒多模型自适应控制(Robust multiple model adaptive control,RMMAC)的闭环稳定性问题.通过采用基于模型输出误差指标的加权算法取代传统的基于卡尔曼滤波器和贝叶斯后验概率公式的加权算法... 详细信息

研究含有不确定性的连续时间随机被控对象的鲁棒多模型自适应控制(Robust multiple model adaptive control,RMMAC)的闭环稳定性问题.通过采用基于模型输出误差指标的加权算法取代传统的基于卡尔曼滤波器和贝叶斯后验概率公式的加权算法,在权值收敛的前提下,基于虚拟等价系统(Virtual equivalent system,VES)理论给出了此类鲁棒多模型自适应控制系统的闭环稳定性证明,并将结果推广到可以用多个线性系统系统模型进行逼近的一类非线性慢时变被控对象.

关键词：鲁棒多模型自适应控制稳定性虚拟等价系统加权

两个含3,3′-硫代二丙酸配体的锰和铜配合物的合成、晶体结构与性质（英文）

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无机化学学报 2018年第11期34卷 2081-2087页

作者：刘继伟关淑霞谷长生东北石油大学化学化工学院黑龙江省石油与天然气重点实验室大庆163318 广东海洋大学化学与环境学院应用化学系湛江524088

使用3,3′-硫代二丙酸、4,4′-联吡啶和硝酸锰在水热条件下反应合成了1个锰配合物,即{[Mn(DPA)(4,4′-bipy)]·H_2O}_n(1)(DPA=3,3′-硫代二丙酸,4,4′-bipy=4,4′-联吡啶);然后又利用3,3′-硫代二丙酸、1,3-双(4-吡啶基)丙烷和硝酸铜... 详细信息

使用3,3′-硫代二丙酸、4,4′-联吡啶和硝酸锰在水热条件下反应合成了1个锰配合物,即{[Mn(DPA)(4,4′-bipy)]·H_2O}_n(1)(DPA=3,3′-硫代二丙酸,4,4′-bipy=4,4′-联吡啶);然后又利用3,3′-硫代二丙酸、1,3-双(4-吡啶基)丙烷和硝酸铜在水热条件下反应合成了1个铜配合物,即{[Cu(DPA)(bpp)(H_2O)]·H_2O}_n(2)(DPA=3,3′-硫代二丙酸,bpp=1,3-双(4-吡啶基)丙烷)。并对它们分别进行了元素分析、红外光谱、热稳定性、X射线粉末衍射和X射线单晶衍射的表征。结果表明:配合物1和2分别由3,3′-硫代二丙酸配体和不同氮杂环分子以及金属离子构筑,形成了二维层状的结构。氢键和π-π作用进一步将二维结构拓展成三维超分子网络。

关键词： 3,3′-硫代二丙酸 1,3-双(4-吡啶基)丙烷 1,3-双(4-吡啶基)丙烷晶体结构

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基于融合模型的高精度倾角测量系统设计

传感技术学报 2016年第10期29卷 1619-1624页

作者：刘伟李杰王一焕中北大学电子测试技术重点实验室太原030051

针对现有倾角测量在宽范围内误差大的问题,提出了一种基于融合模型的高精度倾角测量系统设计方案,首先通过测量误差机理分析建立双MEMS加速度计的融合模型,再拟定标定方案确定模型相关参数,最后对硬、软件进行设计,可实现0-360°内角度... 详细信息

针对现有倾角测量在宽范围内误差大的问题,提出了一种基于融合模型的高精度倾角测量系统设计方案,首先通过测量误差机理分析建立双MEMS加速度计的融合模型,再拟定标定方案确定模型相关参数,最后对硬、软件进行设计,可实现0-360°内角度的高精度测量。经高精度转台对比实验验证,该设计系统具有功耗低、宽测量范围内精度高等优点,能够实现在宽范围（0-360°）的高精度测量,且测量精度达到±0.05°。

关键词： MEMS加速度计倾角测量融合模型系统标定