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Clustering-based adaptive low-power subframe configuration with load-aware offsetting in dense heterogeneous networks

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Digital Communications and Networks 2022年第5期8卷 843-852页

作者： Dinkisa A.Bulti Jyri Hämäläinen Beneyam B.Haile yihenew wondie School of Electrical and Computer Engineering Addis Ababa Institute of Technology(AAiT)Ethiopia Department of Communication and Networking Aalto UniversityFinland

Heterogeneous Networks(HetNets)and cell densification represent promising solutions for the surging data traffic demand in wireless *** dense HetNets,user traffic is steered toward the Low-Power Node(LPN)when possible to enhance the user throughput and system capacity by increasing the area spectral ***,because of the transmit power differences in different tiers of HetNets and irregular service demand,a load imbalance typically exists among different serving *** offload more traffic to LPNs and coordinate the Inter-Cell Interference(ICI),Third-Generation Partnership Project(3GPP)has facilitated the development of the Cell Range Expansion(CRE),enhanced Inter-Cell Interference Coordination(eICIC)and Further enhanced ICIC(FeICIC).In this paper,we develop a cell clustering-based load-aware offsetting and an adaptive Low-Power Subframe(LPS)*** solution allows the separation of User Association(UA)functions at the User Equipment(UE)and network server such that users can make a simple cell-selection decision similar to that in the maximum Received Signal Strength(max-RSS)based UA scheme,where the network server computes the load-aware offsetting and required LPS periods based on the load conditions of the *** proposed solution is evaluated using system-level simulations wherein the results correspond to performance changes in different service *** show that our method effectively solves the offloading and interference coordination problems in dense HetNets.

关键词： Heterogeneous networks(HetNets) 5G LTE-AUser association Interference coordination Load balancing Cell range expansion Almost blank subframe Further enhanced ICIC Low-power subframe

Effective Wireless Cooperative Scheme for Increasing Throughput with Low Outage Probability

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通讯和计算机（中英文版） 2014年第2期11卷 179-186页

作者： yihenew wondie Marye Hua-An Zhao Department of computer Science and Electrical Engineering Kumamoto University Kumamoto 860-8555 Japan

Cooperative communications is an emerging technique in wireless communication to ensure reliability in providing high data rate services. It provides diversity for devices that are incapable of harboring multiple antennae by emulating MIMO (multiple-input-multiple-output) system through virtual antenna array. Several wireless cooperative strategies already exist differing on the process performed at the relay. The common ones are AF (amplify-and-forward) and DF (decode-and-forward). Different strategies have varying throughput performance depending on the relaying complexity and degree of CSI usage. Therefore, cooperative scheme that implements CSI better to improve throughput while keeping outage probability and BER (bit error rate) low is worth looking for. In this paper, an approach using CSI with MRC (maximal ratio combing) at the destination is proposed to improve performance. The process at the relay is also simplified as it uses reduced estimation domain with high precision unlike previous estimation techniques. It will be shown that this new strategy attains better BER and outage performances compared to AF and DF. Simulation results also show that it has better throughput performance at low outage probability as well.

关键词：无线通信中断概率协作产量低多输入多输出天线阵列高数据速率最大比合并

基于SincNet与孪生LSTM网络的说话人确认方法研究

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基于SincNet与孪生LSTM网络的说话人确认方法研究

作者： yihenew Alemu Haile 哈尔滨工业大学

学位级别：硕士

说话人确认技术能够通过语音来判断其所属说话人的身份。目前,基于深度神经网络（deep neural networks,DNN）的方法可以取得较为理想的性能,但仍然存在一些亟待解决问题。具体而言,目前的方法在前端特征提取时解释性不强;同时,在提取... 详细信息

说话人确认技术能够通过语音来判断其所属说话人的身份。目前,基于深度神经网络（deep neural networks,DNN）的方法可以取得较为理想的性能,但仍然存在一些亟待解决问题。具体而言,目前的方法在前端特征提取时解释性不强;同时,在提取后端嵌入（embedding）特征时,对时序信息的考虑也不够充分。此外,还需要考虑梯度消失的问题。针对以上问题,本文的主要研究内容与创新工作如下:（1）提出一种基于SincNet与长短时记忆（long short-term memory,LSTM）相结合的神经网络架构,其能够提取具有更多解释性与时序信息的embedding特征。其中,前端采用SincNet网络,通过利用sinc函数来模拟获得滤波器的相应特性。后端则采用具有softmax损失的LSTM来模拟说话人声道产生声音的过程。同时,LSTM也可以通过保留反向传播中的误差残留,来有效缓解梯度消失的问题。此外,所提出的方法也可以以端到端的形式学习原始波形映射到embedding特征的映射过程。实验结果表明,所提出方法的性能优于基线系统。（2）提出一种基于SincNet与孪生（Siamese）LSTM结合的神经网络改进框架。在此框架中,为了避免相同与不同说话人之间的混淆,采用具有共享参数的孪生网络。孪生网络的对比损失（contrastive loss）函数能够将相同说话人的距离拉近、不同说话人的距离拉远。同时,孪生网络的对比损失函数能够直接计算一对样本之间的距离并进行对比。实验结果表明,相比于上一个方法以及其他基线方法,所提出的改进框架能够获得更好的性能。

关键词：说话人确认深度神经网络 SincNet 长短期记忆网络孪生网络

Effect of Soil and Water Conservation Measures on Selected Soil Physical and Chemical Properties and Barley （Hordeum spp.） Yield

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Journal of Environmental Science and Engineering 2011年第11期5卷 1483-1495页

作者： Tadele Amdemariam yihenew G. Selassie Mitiku Haile C. Yamoh Department of Natural Resources Management College of Agriculture and Natural Resources Debremarkos UniversityDebremarkos Ethiopia Department of Natural Resources Management College of Agriculture and Environmental Sciences Bahir Dar University BahirDar Ethiopia Department of Land Resource Management and Environmental Protection College of Dry Land Agriculture and NaturalResources Mekele University Mekele Ethiopia

A study was conducted in 2007/2008 at Absela locality, Banja Shikudad District of the Amhara National Regional State, Ethiopia to evaluate the effects of soil bunds stabilized with vetiver grass （IT. zizanioides） and tree lucerne （C. palmensis） on soil physical and chemical properties, bund height, inter-terrace slope and barley （Hordeum vulgare L.） yield. Data were analyzed using one-way analysis of variance （ANOVA） and mean values for the treatments were separated using Duncan＇s Multiple Range Test. Results indicated that the non-conserved fields had significantly （p 〈 0.05） lower organic carbon and was found to contain 66% less OM from the average of the conserved treatment. 9-year old sole soil bund, the 9-year old soil bund stabilized with tree lucerne, the 9-year old soil bund stabilized with vetiver, and the 6-year old soil bund stabilized with tree lucerne had 71.20, 68.56, 52.30, and 36.12%, respectively higher percent OM than the control treatment. The trend was similar for total nitrogen. The non-conserved treatment had a higher bulk density when compared to the conserved fields. Fields with soil bunds stabilized with vetiver grass had the highest bund height and the lowest inter-terrace slope than fields treated with the rest of remaining conservation measures. Barley grain yields were significantly （P 〈 0.05） greater in both the soil accumulation and loss zones of the conserved fields than the non-conserved （control） treatment. Practicing soil conservation measures and curtailing causes of land degradation could improve the soil physical and chemical properties thereby increase land productivity of the conserved land.

关键词： Organic carbon soil bund total N tree lucerne vetiver