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Throughput analysis for relay-aided interference channel in cognitive radio networks

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High Technology Letters 2011年第4期17卷 344-349页

作者： Lou Jia luo tao Yue Guangxin School of Information and Communication Engineering Beijing University of Posts and Telecommunications Beijing 100876 P.R. China

This paper considers a two-user Gaussian interference channel aided by a single relay. Two source-destination pairs and the relay share a single common chaunel, and the relay assists both sources in communicating the messages to their respective destinations. This paper mainly focuses on the ＂amplify-and-forward＂（AF） relaying strategy for relay, and derives upper bound and lower bound on achievable sum rate accordingly. Next, the application of the above model in cognitive radio （CR） networks is considered. The schemes that can ensure the coexistence of the secondary user with the primary user are proposed, in the sense that there is no rate degradation for the primary user due to sharing of the channel. Further, the throughput of the secondary user in different communication scenarios is investigated.

关键词： interference channel relay achievable sum rate cognitive radio(CR) throughput

普通铅对LA-ICP-MS磷灰石U-Pb定年结果的影响及校正方法

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岩矿测试 2025年第1期44卷 51-62页

作者：罗涛王瀚林朱松柏卿丽媛胡兆初中国地质大学(武汉)地质过程与矿产资源国家重点实验室湖北武汉430074 中国石油塔里木油田公司克拉采油气管理区新疆库尔勒841000

磷灰石是火成岩、变质岩和沉积岩中广泛分布的含铀矿物,开展磷灰石U-Pb年代学研究对揭示岩浆演化过程、示踪溯源等方面具有重要意义。激光剥蚀电感耦合等离子体质谱法(LA-ICP-MS)是开展磷灰石U-Pb年龄微区分析的重要手段之一。当前,基... 详细信息

磷灰石是火成岩、变质岩和沉积岩中广泛分布的含铀矿物,开展磷灰石U-Pb年代学研究对揭示岩浆演化过程、示踪溯源等方面具有重要意义。激光剥蚀电感耦合等离子体质谱法(LA-ICP-MS)是开展磷灰石U-Pb年龄微区分析的重要手段之一。当前,基体匹配磷灰石U-Pb定年矿物标样缺乏和标样中不可避免的普通铅是制约LA-ICP-MS高精度磷灰石U-Pb年龄分析的主要瓶颈。本文对比研究了标样中普通铅对LA-ICP-MS磷灰石U-Pb定年结果的影响,采用含普通铅的磷灰石MAD作外标直接开展U-Pb年龄校正,获得的被测样品年龄会产生显著的系统偏差(最大约6%);采用207Pb法或Tera-Wasserburg图解法先校正标样中普通铅,再利用校正后的数据进行元素分馏和仪器漂移校正则可获得准确的磷灰石U-Pb年龄,与推荐值偏差在2%以内。另一方面,为消除标样中普通铅对分析结果的影响,本文还采用水蒸气辅助激光剥蚀方法,实现以NIST612玻璃作为外标准确分析磷灰石U-Pb年龄,解决了磷灰石U-Pb定年微区分析高质量标样缺乏的难题。本研究通过对标样中普通铅进行预校正或采用非基体匹配分析,建立了高精度LA-ICP-MS磷灰石U-Pb定年新方法,将促进磷灰石U-Pb年代学在地球科学研究中的应用。

关键词：激光剥蚀电感耦合等离子体质谱法磷灰石 U-Pb定年普通铅校正非基体匹配分析

Phytic Acid Contents of Wheat Flours from Different Mill Streams

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Agricultural Sciences in China 2010年第11期9卷 1684-1688页

作者： WU Peng ZHAO tao TIAN Ji-chun State Key Laboratory of Crop Biology Shandong Agricultural University Tai ＇an 271018 P.R.China College of Food Science and Engineering Shandong Agricultural University Tai＇an 271018 P.R.China College of Horticulture Science and Engineering Shandong Agricultural University Tai ＇an 271018 P.R. China

The phytic acid contents of eight fractions of wheat flours from different mill streams and those in wheat brans, which were separated by different sieves into various sizes, were determined and analyzed. A rapid method for phytic acid assay by adding thioglycolic acid （mercapto acetic acid） with 2,2-bipyridine was used, with an acidic iron-Ⅲ-solution of known iron content. The amount ofphytate was indicated by the decrease in iron in the supernatant. Significant differences were observed in phytic acid content among different milling streams and different cultivars （P〈0.05）. On an average, coarse bran had the highest phytic acid content （53.85 mg g^-1）, and the shorts had 28.48 mg g^-1. The B5 break flour had a higher phytic acid content （4.8 mg g^-1） than the B7 （2.75 mg g^-1） and B8 （2.03 mg g^-1） reduction flours. Lower values were found in the B3, B6 and B7 flours （1.07, 0.79, and 0.76 mg g^-1, respectively）. The phytic acid contents of bran decreased with smaller bran sizes, ranging from 54 to 5.09 mg g^-1.

关键词： phytic acid wheat mill streams bran flour

Organic matter occurrence and pore-forming mechanisms in lacustrine shales in China

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Petroleum Science 2022年第4期19卷 1460-1472页

作者： Li-chun Kuang Lian-Hua Hou Song-tao Wu Jing-Wei Cui Hua Tian Li-Jun Zhang Zhong-Ying Zhao Xia luo Xiao-Hua Jiang Science and Technology R&D Department CNPCBeijing100000China Research Institute of Petroleum Exploration and Development CNPCBeijing100083China National Energy Tight Oil and Gas R&D Center Beijing100083China Key Laboratory of Oil and Gas Reservoirs CNPCBeijing100083China

The evolution of pore structure in shales is affected by both the thermal evolution of organic matter(OM)and by inorganic diagenesis,resulting in a wide variety of pore *** paper examines the OM distribution in lacustrine shales and its influence on pore structure,and describes the process of porosity *** principal findings are:(i)Three distribution patterns of OM in lacustrine shales are distinguished;laminated continuous distribution,clumped distribution,and stellate scattered *** differences in total organic carbon(TOC)content,free hydrocarbon content(S_(1)),and OM porosity among these distribution patterns are discussed.(ii)Porosity is negatively correlated with TOC and plagioclase content and positively correlated with quartz,dolomite,and clay mineral content.(iii)Pore evolution in lacustrine shales is characterized by a sequence of decreasing-increasing-decreasing porosity,followed by continuously increasing porosity until a relatively stable condition is reached.(iv)A new model for evaluating porosity in lacustrine shales is *** this model,the organic and inorganic porosity of shales in the Permian Lucaogou Formation are calculated to be 2.5%-5%and 1%-6.3%,respectively,which correlate closely with measured *** findings may provide a scientific basis and technical support for the sweet spotting in lacustrine shales in China.

关键词： Shale oil Unconventional oil and gas Organic matter Pore evolution Log interpretation model

Megacrysts in the Cenozoic basalt of the Tuoyun Basin,Southwest Tianshan

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Science China Earth Sciences 2007年第1期50卷 55-66页

作者： LÜ YongJun luo ZhaoHua REN ZhongBao LIANG tao State Key Laboratory of Geological Processes and Mineral Resources China University of GeosciencesBeijing 100083China

Abundant megacrysts of clinopyroxene, amphibole, anorthoclase, and phlogopite are found together with deep-seated xenoliths in the Cenozoic basalt of the Tuoyun Basin, Southwest Tianshan. The megacrysts are mainly in the cone sheet formed at the early stage of the volcanic activity. Clinopyroxene megacrysts are located in the lower part of the profile, with amphibole and phlogopite megacrysts in the middle part and anorthoclase megacrysts in the upper part. The crystal integrity, absence of deformation fabric and their relation to the host basalt suggest that they were crystallized from the host magma and quickly transported to the surface. The mineralogical studies imply that the clinopyroxene megacrysts are of Al-augite with higher Al2O3 (>9%). Amphibole megacrysts are kaersutite rich in TiO2 (>4.5%). Sulfide inclusions such as pyrrhotite occur in some clinopyroxene and amphibole megacrysts. Thermodynamic calculations reveal that pyroxene megacrysts formed under the temperature of 1185.85–1199.85°C and the pressure between 1.53 and 1.64 GPa comparable to the crust-mantle boundary and amphibole megacrysts crystallized under the pressure of around 0.85 GPa, temperature about 1000°C comparable to the depth of 30 km. Anorthoclase megacrysts crystallized under the pressure between 0.8–1 GPa, temperature about 900°C. The absence of Ti-rich inclusions such as rutile can be considered as an evidence of quick magma ascending. The P-T conditions estimated via pyroxene megacrysts and phenocrysts compose a P-T path with a steep slope. It can be considered as another evidence of quick magma ascending. However, the estimated temperatures for amphibole megacrysts are markedly lower than those for pyroxene megacrysts given the same pressure. It probably shows that the amphiboles have crystallized at the vanguard of magma and under the volatile-rich condition. Thus, we can conclude that the Cenozoic basalts are produced in an extensional tectonic setting and the processes governin

关键词： Tuoyun Basin megacryst clinopyroxene amphibole anorthoclase alkaline basalt Tianshan.

Hierarchical clustering driven by cognitive features

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Science China(Information Sciences) 2014年第1期57卷 111-124页

作者： LI chunZhong XU ZongBen QIAO Chen luo tao Institute of Statistics and Applied Mathematics Anhui University of Finance and Economics Institute for Information and System Science Xi'an Jiaotong University

For data sets of arbitrary shapes and densities,the existing clusterings have much space to be improved to obtain better *** this paper,clustering is considered as a cognitive problem,and cognitive features are of vital importance to *** combination with psychological experiment,we propose three cognitive features of clustering and model them as a flexible similarity *** a new clustering framework is put forward to integrate the cognitive features by employing the similarity *** two attractive advantages are its low complexity and fitness for various types of data sets,such as data sets of diferent shapes and *** synthetic and real data sets are employed to exhibit the superiority of the new clustering algorithm.

关键词： clustering direction consistent structural nearest neighborhood afecting field manifold

MODELING ON DYNAMIC PROCESS OF MEMBRANE FOULING DURING FINITE CROSSFLOW ULTRAFILTRATION IN CHARGED SYSTEM

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Journal of Hydrodynamics 2006年第2期18卷 206-210页

作者： luo Ming-Liang PU chun-sheng ZHAO Jian-qing College of Petroleum Engineering China University of Petroleum （East China） Dongying 257061 China College of Materials Science and Engineering South China University of Technology Guangzhou 510640 China

Flux decline during finite crossflow Ultrafiltration（UF） in charged system was investigated by perceiving membrane fouling as a dynamic process from non-equilibrium to equilibrium. Under the influence of the boundary condition at the initial section and cross flow, the equilibrium is first reached at the initial section of the crossflow filter and the front of the equilibrium region progresses with time toward the end of the filter. A mathematic model was developed to describe this dynamic process of membrane fouling in a charged system. With the model, the time-dependent flux and the time required to reach the steady state in a crossflow filtration can be easily determined. The fouling process under different conditions is simulated as illustrated with a demonstration of the newly developed model. The resulls of simulation show that there are jumps in the local flux at the front of the equilibrium region and the electrokinetic properties of charged UF system have a very substantial influence on the separation performance of membrane.

关键词： fouling dynamics flux decline,Ultrafiltration(UF) charged system modeling

Link Maintenance Scheme for OFDM-Based Cognitive Radio Ad Hoc Networks

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China Communications 2015年第10期12卷 42-51页

作者： LI Jingye luo tao LIU Xuelian YUE Guangxin Beijing Key Laboratory of Network System Architecture and Convergence Beijing University of Posts and Telecommunications

Transmission among the cognitive users(CUs)' is always interrupted by the primary users(PUs)' reclaim of the spectrum and the fading effect of wireless *** maintain reliable continuous communication among CUs,an efficient scheme for link maintenance in OFDM-based cognitive radio Ad Hoc networks is proposed in this *** the scheme,redundant sub-channels(RSC) are employed by CUs to tackle the outage problem caused by the PUs' reclaim of the spectrum and wireless fading effect in the ***,backup sub-channels(BSC) are arranged to help select sub-channels with better channel ***,to lower the overhead and improve the accuracy of the spectrum sensing,a partial sensing module is designed to enable the CUs to inherit and update the original idle spectrum list until it *** results show that the proposed scheme can realize higher throughput and lower sensing overhead with slight reduction of the forced termination probability(FTP) performance compared to the existing approaches.

关键词： cognitive radio link maintenance sensing overhead

Recombinant Apoptin Gene Retrovirus Induces Apoptosis in Human Breast Cancer Cells 435

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Chinese Journal of Cancer Research 2009年第3期21卷 194-201页

作者： chun-mei Yu Hai-tao Xu Jie Du Department of Breast Center Beijing Chuiyangliu Hospital Beijing 100022 China Department of Abdominal Surgery the Third Affiliated Hospital Harbin Medical University Harbin 150086 China Department of Biology Graduate School Chinese Academy of Sciences Beijing 100049 China

Objective： To construct recombinant Apoptin gene （vp3） retrovirus pLVP3 and to study its apoptosis inducing effect on human breast cancer cells 435 as well as to discuss its mechanism in vitro and in vivo. Methods： vp3 gene was cloned and recombinated into retrovirus vector pLP-LNCX-VP3 （pLVP3） at loxP site, which was transformed into package cell line PT67 and then into NIH3T3 cells for titer assay. The human breast cancer cell line 435 was infected with retrovirus pLVP3, and then MTT assay and Western blotting were adopted to detect cellular proliferation and Apoptin protein expression. Forty-eight hours after infection flow cytometry （FCM） was used for apoptosis detection and Surface Enhanced Laser Desorption Ionization-Time of Flight-Mass Spectrometry （SELDI-TOF-MS） was used for protein profile assay. Nude mice model of human breast cancer cells 435 was set up to observe the tumor inhibiting rates of pLVP3, and TUNEL assay was used to detect tumor apoptosis as well as real-time PCR for vp3 gene expression. Results： Recombinant plasmid pLVP3 was successfully constructed. Virus titer reached to 5×10^8 pfu/ml in the PT67 culture supernatant. Forty-eight hours after infection, cellular inhibition rate was 65.1% in MTT assay, higher than that in blank control （P〈0.05） and Apoptin protein expressed more in test group in Western blotting. FCM assay showed apoptotic peaks with a percentage of 15.42%. SELDI-TOF-MS findings suggested that two protein peaks, M_2544.1＋H and M_3712.4＋H, were statistically different between infection group and control group （P〈0.05）. The tumor inhibition rates in pLVP3 group were 65.52% and 68.23%, much higher than that of control group （t=4.06, P〈0.01）. TUNEL assay findings showed that positive yellow stains were seen in pLVP3 retrovirus group and 5-FU positive control group without difference （t1=1.05, t2=0.84, P〉0.05）. Conclusion： The experiment demonstrated that vp3 could induce apoptosis in tumor cells in vivo and in vitro, whic

关键词： Apoptin Retrovirus Gene therapy Breast cancer