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黄河流域史前音乐考古与中华音乐文明的起源

中国音乐 2024年第2期 5-15页

作者：方建军天津音乐学院中央音乐学院

根据目前黄河流域的史前音乐考古发现,在距今约8000年的新石器时代早期,中华音乐文明在中原地区起源,在距今约5000年的新石器时代晚期,中华音乐文明已经形成,并在黄河流域呈多点分布。史前时期的中华音乐文明应是多地区、多民族的共同... 详细信息

根据目前黄河流域的史前音乐考古发现,在距今约8000年的新石器时代早期,中华音乐文明在中原地区起源,在距今约5000年的新石器时代晚期,中华音乐文明已经形成,并在黄河流域呈多点分布。史前时期的中华音乐文明应是多地区、多民族的共同创造。史前音乐所体现的仪式性因素,本身就包含着礼的义涵。史前墓葬资料所呈现的社会分化现象显示,音乐物质产品的拥有者应是都邑或聚落中心的首领或执掌特殊权力的人物,乐器成为他们身份地位的象征。乐与礼的结合是史前音乐文明的重要标志,礼乐内涵应是史前音乐文明起源和形成的判断标准,音乐文明业已成为中华文明起源与形成的重要组成部分和主要精神标识。

关键词：黄河流域史前音乐考古中华音乐文明起源

Role of ammonium sulfate in sulfurization flotation of azurite:Inhibiting the formation of copper sulfide colloid and its mechanism

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International Journal of Mining Science and Technology 2022年第3期32卷 575-584页

作者： Jinpeng Cai Chao Su Yinyu Ma Xingcai Yu Rong Peng Jiangli Li Xiaolin Zhang jianjun fang Peilun Shen Dianwen Liu State Key Laboratory of Complex Nonferrous Metal Resources Clean Utilization Yunnan Key Laboratory of Green Separation and Enrichment of Strategic Metal ResourcesFaculty of Land Resources EngineeringKunming University of Science and TechnologyKunming 650093China Shandong Gold Group Co. LtdJinan 250014China Yunnan Posphate Group Co. LtdKunming 650600China

In this study,the role of(NH_(4))_(2)SO_(4)during the sulfurization of azurite and its response to flotation were investigated.The flotation results showed that adding(NH_(4))_(2)SO_(4)prior to sulfurization decreased the formation of colloid in flotation pulp,and the floatability of the suppressed azurite caused by excess sodium sulfide was restored.After adding(NH_(4))_(2)SO_(4)prior to sulfurization,the formation of Cu(NH_(3))_(n) ^(2+)intermediate products changed the path of the sulfurization reaction,which slowed the direct impact of HSon the azurite surface.The nucleation rate was reduced,and the growth of copper sulfide crystal was improved.Covellite(syn,CuS)with larger crystal grains was formed on the azurite surface,thereby enhancing the mechanical stability of copper sulfide products onto the mineral surface.Therefore,the generated copper sulfide colloid significantly reduced,ultimately promoting the effective adsorption of xanthate on the azurite surface.

关键词： Azurite Sulfurization flotation Ammonium sulfate Colloid Inhibition Crystal growth

Output Tracking Control of a Hydrogen-air PEM Fuel Cell

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IEEE/CAA Journal of Automatica Sinica 2017年第2期4卷 273-279页

作者： Shiwen Tong jianjun fang Yinong Zhang College of Automation Beijing Union UniversityBeijing 100101China

Hydrogen-air proton exchange membrane(PEM)fuel cell is a promising clean energy. However, the stack output tracking control is still a challenging problem due to the soft characteristic of the stack. Both over-and less-control will cause the stack flooding or oxygen lacking which dramatically decreases the life of stacks. Traditional control methods rely on the accurate model of the fuel cell system, which is a high-order nonlinear system, and involve a complex controller design process. This paper combines the data-based fuzzy cluster modeling technology with the sliding mode control and the integral actions. The sliding mode controller tracks the dynamic changes of the fuel cell system and the integral controller eliminates the steady-state errors. Simulation results demonstrate good performance of the proposed control method.

关键词： Fuel cell fuzzy cluster modeling integral compensation sliding mode control

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清华简《乐风》曲谱解译

人民音乐 2024年第1期 63-66页

作者：方建军郑州大学天津音乐学院中央音乐学院

《清华大学藏战国竹简》第十三辑,刊布有《五音图》和《乐风》两种音乐文献①,具有重要的音乐史料价值。笔者曾对这两篇简文试做初步探索②,认为《乐风》当为一首歌曲作品的名称,其中第一部分内容包含五正声和个别偏音,可能是歌唱和伴... 详细信息

《清华大学藏战国竹简》第十三辑,刊布有《五音图》和《乐风》两种音乐文献①,具有重要的音乐史料价值。笔者曾对这两篇简文试做初步探索②,认为《乐风》当为一首歌曲作品的名称,其中第一部分内容包含五正声和个别偏音,可能是歌唱和伴奏通用的乐谱,也是目前所见最早的宫商字谱,并推测《乐风》的唱词,应是类似于《诗经》的四言诗。第二部分内容可能是琴的演奏提示和说明。今就《乐风》的宫商字谱再做进一步解析,并将其试译为今谱,以就教于读者。

关键词：四言诗《诗经》音乐史料歌曲作品音乐文献清华简

Design of a Networked Tracking Control System With a Data-based Approach

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IEEE/CAA Journal of Automatica Sinica 2019年第5期6卷 1261-1267页

作者： Shiwen Tong Dianwei Qian Xiaoyu Yan jianjun fang Wei Liu the College of Robotics Beijing Union UniversityBeijing 100101and also with Beijing Key Laboratory of Information Service EngineeringBeijing Union UniversityBeijing 100101China the School of Computer and Control Engineering North China Electric Power UniversityBeijing 102206China the Graduate School Beijing Union UniversityBeijing 100101China the College of Urban Rail Transit and Logistics Beijing Union UniversityBeijing 100101China

Tracking control is a very challenging problem in the networked control system(NCS), especially for the process with blurred mechanism and where only input-output data are available. This paper has proposed a data-based design approach for the networked tracking control system(NTCS). The method utilizes the input-output data of the controlled process to establish a predictive model with the help of fuzzy cluster modelling(FCM)technology. Then, the deduced error and error change in the future are treated as inputs of a fuzzy sliding mode controller(FSMC) to obtain a string of future control actions. These candidate control actions in the controller side are delivered to the plant side. Thus, the network induced time delays are compensated by selecting appropriate control action. Simulation outputs prove the validity of the proposed method.

关键词： Delay compensation fuzzy cluster modeling (FCM) fuzzy sliding mode control (FSMC) networked tracking control(NTC)

Control strategy for wayside supercapacitor energy storage system in railway transit network

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Journal of Modern Power Systems and Clean Energy 2014年第2期2卷 181-190页

作者： Zongyu GAO jianjun fang Yinong ZHANG Di SUN College of Automation of Beijing Union University Beijing 100101China School of Electrical Engineering Beijing Jiaotong UniversityBeijing 100044China

This paper discusses the control strategy for energy management in railway transit network with wayside(substation)supercapacitor(SC)energy storage system(ESS).Firstly,the structure of the wayside energy storage system is introduced.Secondly,the model of energy storage system is built and the control strategy is described.Thirdly,in order to estimate the required energy storage system,a useful method is proposed to predict the instantaneous regenerative energy magnitude which is delivered to each substation.Finally,the ESS configuration for each substation is determined.A simplified mathematical model of the whole metro network is established and the main features of the control strategy are developed.Numerical simulations show the efficacy of suggested control strategy and the energy saving obtained for railway transit network.

关键词： Supercapacitor(SC) Energy storage system(ESS) Regeneration failure Control strategy Railway transit network

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光储直柔在整县光伏开发中的应用分析

建筑节能（中英文） 2024年第1期52卷 120-123页

作者：房建军国华能源投资有限公司北京102211

整县屋顶分布式光伏开发试点过程中面临着光伏项目并网困难、就地消纳能力不足等技术难题。介绍光储直柔新型电力系统技术,分析在整县光伏推进工作中采用光、储、直、柔等技术解决以上两个难题面临的机遇与挑战,并给出相应的建议。分析... 详细信息

整县屋顶分布式光伏开发试点过程中面临着光伏项目并网困难、就地消纳能力不足等技术难题。介绍光储直柔新型电力系统技术,分析在整县光伏推进工作中采用光、储、直、柔等技术解决以上两个难题面临的机遇与挑战,并给出相应的建议。分析山西芮城县东夭村国内首个农村“光储直柔”低压直流系统在新能源消纳、安全性和可靠性等方面的优势和经济效益。分析国家能源集团BIPV中心采用“光储直柔”技术,利用建筑的立面和屋顶实现较大规模的光伏装机量,实现光伏发电就地消纳和柔性供用能。推广光储直柔技术是解决整县分布式光伏大规模开发中并网难和就地消纳不足等技术难点的有效途径之一。

关键词：光储直柔整县光伏就地消纳应用分析

Growth of covellite crystal onto azurite surface during sulfurization and its response to flotation behavior

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International Journal of Mining Science and Technology 2021年第6期31卷 1003-1012页

作者： Jinpeng Cai Peilun Shen Dianwen Liu Xiaolin Zhang jianjun fang Chao Su Xingcai Yu Jiangli Li Han Wang State Key Laboratory of Complex Nonferrous Metal Resources Clean Utilization Faculty of Land Resources EngineeringKunming University of Science and TechnologyKunming 650093China

In this work,the growth of copper sulfide crystal onto azurite surfaces during sulfurization and its response to flotation are investigated.Filed emission scanning electron microscopy-energy dispersive X-ray spectroscopy(FESEM) and X-ray diffraction(XRD) studies confirmed that the sulfurization of azurite is not limited to the mineral surface,but rather penetrates into the bulk to form covellite crystal(synCuS),creating favorable conditions for the stable adsorption of xanthate and greatly promoting the azurite flotation.Additionally,as demonstrated by X-ray photoelectron spectroscopy(XPS) and time of flight secondary ion mass spectrometry(TOF-SIMS) analyses,a redox reaction occurred during this process,and Cu(Ⅱ) onto the mineral surface was reduced to Cu(Ⅰ).Correspondingly,reduced S^(2-) was oxidized to(S_(2))^(2-),(S_n)^(-2),and even to deeper oxidation state S~0,(S_(x)O_(y))^(n-) and SO_(4)^(2-).Excess sodium sulfide strengthens copper sulfide to form onto the azurite surface,and provides enough raw material for crystal copper sulfide to grow,resulting in the formation of "flake-like" covellite with a better crystallinity.However,the floatability of azurite decreased dramatically under this condition,because the generated massive colloidal copper sulfide in flotation pulp deteriorates the flotation environment,resulting in a decreased effective adsorption of collector onto azurite surfaces.

关键词： Azurite Sulfurization floatation Covellite crystal Growth Colloid

基于PVsyst的屋顶光伏电气系统优化设计

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绿色建筑 2024年第1期16卷 52-57,68页

作者：杜军房建军国家能源集团绿色能源与建筑研究中心北京102211

随着光伏技术的飞速发展,光伏发电已进入平价上网阶段。为了达到光伏发电效益最大化,需要对光伏发电电气系统进行优化设计。以北京地区混凝土屋顶分布式光伏发电项目为例,通过对光伏组件最佳角度的设置、安装间距的调整以及系统容配比... 详细信息

随着光伏技术的飞速发展,光伏发电已进入平价上网阶段。为了达到光伏发电效益最大化,需要对光伏发电电气系统进行优化设计。以北京地区混凝土屋顶分布式光伏发电项目为例,通过对光伏组件最佳角度的设置、安装间距的调整以及系统容配比的选择,利用光伏设计软件PVsyst设计光伏电气系统并进行方案对比分析,得出最佳的优化设计方案,为后续光伏系统设计提供参考和借鉴。

关键词： PVsyst 屋顶光伏电气系统优化设计