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Nighttime Construction Noise Disturbance Compensation in Beijing:Taking the Tongzhou New Campus Project of Renmin University of China as an Example
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作者 feng zhou 《Journal of World Architecture》 2023年第6期82-88,共7页
By examining a specific case of compensating for nighttime construction noise in Beijing’s construction projects,we explored how the costs of mitigating construction noise disturbance could be fairly distributed amon... By examining a specific case of compensating for nighttime construction noise in Beijing’s construction projects,we explored how the costs of mitigating construction noise disturbance could be fairly distributed among multiple construction projects near residential areas.In this process,the local government played a crucial coordinating role.According to regulations,construction units must include the costs of preventing and controlling construction noise pollution in the project cost.The construction contract should clearly specify the construction unit’s responsibility for noise pollution prevention and control.After signing the contract,the construction unit should promptly undertake relevant measures to minimize disturbances caused by nighttime construction,aiming to reduce the adverse impacts on the community and ensure the smooth progress of the construction project. 展开更多
关键词 Construction noise disturbance compensation Construction management Noise Civil disturbances
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Collaborative positioning for swarms:A brief survey of vision,LiDAR and wireless sensors based methods
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作者 Zeyu Li Changhui Jiang +3 位作者 Xiaobo Gu Ying Xu feng zhou Jianhui Cui 《Defence Technology(防务技术)》 SCIE EI CAS CSCD 2024年第3期475-493,共19页
As positioning sensors,edge computation power,and communication technologies continue to develop,a moving agent can now sense its surroundings and communicate with other agents.By receiving spatial information from bo... As positioning sensors,edge computation power,and communication technologies continue to develop,a moving agent can now sense its surroundings and communicate with other agents.By receiving spatial information from both its environment and other agents,an agent can use various methods and sensor types to localize itself.With its high flexibility and robustness,collaborative positioning has become a widely used method in both military and civilian applications.This paper introduces the basic fundamental concepts and applications of collaborative positioning,and reviews recent progress in the field based on camera,LiDAR(Light Detection and Ranging),wireless sensor,and their integration.The paper compares the current methods with respect to their sensor type,summarizes their main paradigms,and analyzes their evaluation experiments.Finally,the paper discusses the main challenges and open issues that require further research. 展开更多
关键词 Collaborative positioning VISION LIDAR Wireless sensors Sensor fusion
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Electron-distribution control via Pt/NC and MoC/NC dual junction:Boosted hydrogen electro-oxidation and theoretical study
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作者 feng zhou Xiaofeng Ke +8 位作者 Yihuang Chen Mei Zhao Yun Yang Youqing Dong Chao Zou Xi’an Chen Huile Jin Lijie Zhang Shun Wang 《Journal of Energy Chemistry》 SCIE EI CAS CSCD 2024年第1期513-520,I0011,共9页
The scarcity,high cost and susceptibility to CO of Platinum severely restrict its application in alkaline hydrogen oxidation reaction(HOR).Hybridizing Pt with other transition metals provides an effective strategy to ... The scarcity,high cost and susceptibility to CO of Platinum severely restrict its application in alkaline hydrogen oxidation reaction(HOR).Hybridizing Pt with other transition metals provides an effective strategy to modulate its catalytic HOR performance,but at the cost of mass activity due to the coverage of modifiers on Pt surface.Herein,we constructed dual junctions'Pt/nitrogen-doped carbon(Pt/NC)andδ-MoC/NC to modify electronic structure of Pt via interfacial electron transfer to acquire Pt-MoC@NC catalyst with electron-deficient Pt nanoparticles,simultaneously endowing it with high mass activity and durability of alkaline HOR.Moreover,the unique structure of Pt-MoC@NC endows Pt with a high COtolerance at 1,000 ppm CO/H_(2),a quality that commercial Pt-C catalyst lacks.The theoretical calculations not only confirm the diffusion of electrons from Pt/NC to Mo C/NC could occur,but also demonstrate the negative shift of Pt d-band center for the optimized binding energies of*H,*OH and CO. 展开更多
关键词 Hydrogen oxidation reaction Dual junctions CO-tolerance PLATINUM
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Spatial Distribution Feature Extraction Network for Open Set Recognition of Electromagnetic Signal
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作者 Hui Zhang Huaji zhou +1 位作者 Li Wang feng zhou 《Computer Modeling in Engineering & Sciences》 SCIE EI 2024年第4期279-296,共18页
This paper proposes a novel open set recognition method,the Spatial Distribution Feature Extraction Network(SDFEN),to address the problem of electromagnetic signal recognition in an open environment.The spatial distri... This paper proposes a novel open set recognition method,the Spatial Distribution Feature Extraction Network(SDFEN),to address the problem of electromagnetic signal recognition in an open environment.The spatial distribution feature extraction layer in SDFEN replaces convolutional output neural networks with the spatial distribution features that focus more on inter-sample information by incorporating class center vectors.The designed hybrid loss function considers both intra-class distance and inter-class distance,thereby enhancing the similarity among samples of the same class and increasing the dissimilarity between samples of different classes during training.Consequently,this method allows unknown classes to occupy a larger space in the feature space.This reduces the possibility of overlap with known class samples and makes the boundaries between known and unknown samples more distinct.Additionally,the feature comparator threshold can be used to reject unknown samples.For signal open set recognition,seven methods,including the proposed method,are applied to two kinds of electromagnetic signal data:modulation signal and real-world emitter.The experimental results demonstrate that the proposed method outperforms the other six methods overall in a simulated open environment.Specifically,compared to the state-of-the-art Openmax method,the novel method achieves up to 8.87%and 5.25%higher micro-F-measures,respectively. 展开更多
关键词 Electromagnetic signal recognition deep learning feature extraction open set recognition
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Average Secrecy Capacity of the Reconfigurable Intelligent Surface-Assisted Integrated Satellite Unmanned Aerial Vehicle Relay Networks
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作者 Ping Li Kefeng Guo +2 位作者 feng zhou XuelingWang Yuzhen Huang 《Computer Modeling in Engineering & Sciences》 SCIE EI 2024年第2期1849-1864,共16页
Integrated satellite unmanned aerial vehicle relay networks(ISUAVRNs)have become a prominent topic in recent years.This paper investigates the average secrecy capacity(ASC)for reconfigurable intelligent surface(RIS)-e... Integrated satellite unmanned aerial vehicle relay networks(ISUAVRNs)have become a prominent topic in recent years.This paper investigates the average secrecy capacity(ASC)for reconfigurable intelligent surface(RIS)-enabled ISUAVRNs.Especially,an eve is considered to intercept the legitimate information from the considered secrecy system.Besides,we get detailed expressions for the ASC of the regarded secrecy system with the aid of the reconfigurable intelligent.Furthermore,to gain insightful results of the major parameters on the ASC in high signalto-noise ratio regime,the approximate investigations are further gotten,which give an efficient method to value the secrecy analysis.At last,some representative computer results are obtained to prove the theoretical findings. 展开更多
关键词 Integrated satellite unmanned aerial vehicle relay networks reconfigurable intelligent surface average secrecy capacity(ASC) asymptotic ASC
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Multi-systemic melioidosis in a patient with type 2 diabetes in nonendemic areas:A case report and review of literature
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作者 Huan-Yu Ni Ying Zhang +1 位作者 Dong-Hai Huang feng zhou 《World Journal of Clinical Cases》 SCIE 2024年第9期1669-1676,共8页
BACKGROUND Melioidosis,an infectious disease caused by Burkholderia pseudomallei(B.pseudomallei),occurs endemically in Southeast Asia and Northern Australia and is a serious opportunistic infection associated with a h... BACKGROUND Melioidosis,an infectious disease caused by Burkholderia pseudomallei(B.pseudomallei),occurs endemically in Southeast Asia and Northern Australia and is a serious opportunistic infection associated with a high mortality rate.CASE SUMMARY A 58-year-old woman presented with scattered erythema on the skin of her limbs,followed by fever and seizures.B.pseudomallei was isolated successively from the patient’s urine,blood,and pus.Magnetic resonance imaging showed abscess formation involving the right forehead and the right frontal region.Subsequently,abscess resection and drainage were performed.The patient showed no signs of relapse after 4 months of follow-up visits post-treatment.CONCLUSION We present here a unique case of multi-systemic melioidosis that occurs in nonendemic regions in a patient who had no recent travel history.Hence,it is critical to enhance awareness of melioidosis in non-endemic regions. 展开更多
关键词 MELIOIDOSIS Burkholderia pseudomallei ENDEMIC DIABETES Case report
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257份高粱种质资源农艺性状的遗传多样性 被引量:2
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作者 高旭 冯周 +5 位作者 丁延庆 徐建霞 曹宁 程斌 汪灿 张立异 《西南农业学报》 CSCD 北大核心 2023年第1期1-10,共10页
【目的】探明来自中国的257份高粱种质资源产量相关性状的遗传多样性,为贵州酒用高粱种质资源创新与新品种选育提供理论依据。【方法】对257份高粱种质资源的15个数值型性状和3个描述型性状进行相关性分析、主成分分析和聚类分析,评估... 【目的】探明来自中国的257份高粱种质资源产量相关性状的遗传多样性,为贵州酒用高粱种质资源创新与新品种选育提供理论依据。【方法】对257份高粱种质资源的15个数值型性状和3个描述型性状进行相关性分析、主成分分析和聚类分析,评估其遗传变异情况。【结果】在15个数值型农艺性状中,平均变异系数为19.83%,平均遗传多样性指数为2.04,变异系数以最长一级枝梗最大(33.16%),长宽比最小(9.4%);遗传多样性指数以株高最大(2.09),最长一级支梗最小(1.94)。在3个描述型性状中,籽粒颜色遗传多样性指数最高(1.69),其次是穗形(1.53),穗型最低(1.30)。相关性分析表明,15个数值性状之间存在不同程度的相关性,其中,粒长、粒宽均与长宽比呈极显著正相关(P<0.01),相关系数分别为0.91和0.86,穗长与最长一级支梗数和叶鞘长呈极显著正相关(P<0.01),相关系数分别为0.88和0.81。主成分分析表明,15个数值型农艺性状可分为5个主成分,累积贡献率为82.40%。聚类分析表明,257份高粱种质资源划分为3个类群,类群Ⅰ中的高粱资源具有较大的千粒重,类群Ⅱ中的高粱穗型多为中散型,且株高较矮,类群Ⅲ中的种质主要表现为植株较高。【结论】257份高粱种质资源在18个农艺性状上均表现出丰富的遗传多样性,一些株型相关性状(株高、茎节数、茎粗、叶鞘长、穗柄长、一级枝梗、最长一级枝梗、旗叶长)和籽粒相关性状(千粒重、粒长、粒宽和长宽比)之间呈显著关联性,聚类的3个类群具有一定的区域特性。结合贵州高粱株高较高和千粒重较低的特点,第Ⅰ和第Ⅱ类群的部分种质(郎糯1号、泸州红2号、高08、板江高粱-GX、赤水红粱1号、赤水红粱2号、370、黔高7号、433、茅红糯2号、黔高6号、黔高4号、黔高2号、黔高3号、地丁、睁眼三、7103、371、永123、NMG等)可作为贵州酒用高粱遗传改良的育种亲本。 展开更多
关键词 高粱 遗传多样性 农艺性状 种质资源
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渗透率测井评价:现状及发展方向 被引量:1
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作者 李宁 王克文 +3 位作者 武宏亮 冯周 刘鹏 李雨生 《石油科学通报》 CAS 2023年第4期432-444,共13页
渗透率是十分重要而又难以准确计算的储层参数之一。目前渗透率测井评价主要依据4类方法,即:基于孔渗关系的渗透率评价、基于核磁共振测井的渗透率评价、基于斯通利波测量的渗透率评价以及基于大数据和人工智能的渗透率评价。通过对上... 渗透率是十分重要而又难以准确计算的储层参数之一。目前渗透率测井评价主要依据4类方法,即:基于孔渗关系的渗透率评价、基于核磁共振测井的渗透率评价、基于斯通利波测量的渗透率评价以及基于大数据和人工智能的渗透率评价。通过对上述方法适用性的分析发现,井筒斯通利波与储层孔隙空间流体的流动性密切相关,在储层渗透率评价中具有明显优势。但目前渗透率测井评价面临艰巨挑战,其原因包括3个方面,即:确定渗透率参数本身的理论、实验难度,评价对象复杂性的日益增大和尚未形成能用于井下连续测量渗透率的装备。本文指出,推进斯通利波渗透率评价理论、方法和技术研究,构建新的以斯通利波测量为核心的渗透率评价技术体系是新一代测井技术发展的方向。 展开更多
关键词 渗透率 孔隙度 斯通利波 核磁共振测井 大数据
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饱和度方程一般形式的理论内涵及应用实践
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作者 李宁 王克文 +2 位作者 武宏亮 冯周 田瀚 《中国石油大学学报(自然科学版)》 EI CAS CSCD 北大核心 2023年第5期38-44,共7页
首次将电阻增大率-含油(气)饱和度方程一般形式的不同截短方式形成的矩阵视为一种“周期表”。通过研究纯砂岩、泥质砂岩及典型火山岩、碳酸盐岩储层饱和度方程在矩阵中的分布发现特定的周期变化规律,即当储层导电呈并联模式时其饱和度... 首次将电阻增大率-含油(气)饱和度方程一般形式的不同截短方式形成的矩阵视为一种“周期表”。通过研究纯砂岩、泥质砂岩及典型火山岩、碳酸盐岩储层饱和度方程在矩阵中的分布发现特定的周期变化规律,即当储层导电呈并联模式时其饱和度模型最优截短方式沿周期表的横向作规律性变化;当储层导电呈串联模式时其饱和度模型最优截短方式沿周期表的纵向作规律性变化;当储层导电呈串并联混合模式时其饱和度模型最优截短方式沿周期表的对角线方向作规律性变化。这一周期表可以用来预测不同储层饱和度方程最优截短形式,尤其是对复杂储层饱和度模型的准确确定意义重大,现已在各类复杂储层评价中实际应用。本文中仅以电性受多种因素影响的缝洞型碳酸盐岩和天然气水合物这两类典型储层饱和度模型的确定为例予以说明。 展开更多
关键词 饱和度模型 通解方程 影响因素 截短形式 周期表
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吴翰香教授治疗自身免疫性溶血性贫血的经验
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作者 陆颖佳 邱仲川 +6 位作者 赵琳 黄中迪 胡晓莹 朱小勤 瞿玮颖 封舟 陈珮 《西部中医药》 2023年第1期33-35,共3页
通过1则验案探讨吴翰香教授治疗自身免疫性溶血性贫血(autoimmune hemolytic anemia,AIHA)的临床经验,吴翰香教授认为AIHA患者血不华色、胆色增多,是由内因、外因导致气血败坏而成,根据临床特征分为阳黄证、虚黄证、阴毒证、阳微证、瘀... 通过1则验案探讨吴翰香教授治疗自身免疫性溶血性贫血(autoimmune hemolytic anemia,AIHA)的临床经验,吴翰香教授认为AIHA患者血不华色、胆色增多,是由内因、外因导致气血败坏而成,根据临床特征分为阳黄证、虚黄证、阴毒证、阳微证、瘀黄证,以补益泄利为基本治法,并随症加减,虽不能脱体,但可以改善黄疸、血虚之证。 展开更多
关键词 自身免疫性溶血性贫血 名医经验 吴翰香
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基于Super-GBS的高粱株高和节间数QTL定位
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作者 徐建霞 丁延庆 +5 位作者 冯周 曹宁 程斌 高旭 邹桂花 张立异 《生物技术通报》 CAS CSCD 北大核心 2023年第7期185-194,共10页
株高及相关性状是影响高粱株型和产量的关键因素,定位影响这些性状的主效QTL,为高粱的分子遗传改良提供依据。以美国高粱品种BTx623和贵州酒用高粱品种红缨子杂交构建的包含205个家系的重组自交系(RIL)群体为材料,在5个环境条件下调查... 株高及相关性状是影响高粱株型和产量的关键因素,定位影响这些性状的主效QTL,为高粱的分子遗传改良提供依据。以美国高粱品种BTx623和贵州酒用高粱品种红缨子杂交构建的包含205个家系的重组自交系(RIL)群体为材料,在5个环境条件下调查株高和节间数。利用Super-GBS技术进行基因分型,建立SNP标记遗传图谱,采用完备区间作图法(ICIM)开展QTL定位。结果表明,在第1、3、4、8、9染色体上一共检测到18个QTL,其中,与株高和节间数相关的QTL分别为7和11个。有10个主效QTL在多个环境中或2个性状中被重复检测到,其中q PH9.1与已知的株高基因Dw1一致,而q PH1.2、qPH3.2、qIN3.2以及q IN8.1所在区间内包含了4个与影响水稻株高或节间伸长的基因同源。 展开更多
关键词 高粱 株高 节间数 QTL定位 候选基因
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Viabahn VBX球囊扩张式覆膜支架的初步应用体会
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作者 李佳俊 朱杰昌 +4 位作者 范海伦 冯舟 胡凡果 张益伟 戴向晨 《中国血管外科杂志(电子版)》 2023年第1期33-37,共5页
目的探讨Viabahn VBX球囊扩张式覆膜支架的短期临床应用结果。方法收集2022年6~10月在天津医科大学总医院行VBX支架植入术的27例患者临床资料,对释放成功率、技术成功率、术后30 d临床成功率等治疗结果进行回顾性分析。结果共植入29枚VB... 目的探讨Viabahn VBX球囊扩张式覆膜支架的短期临床应用结果。方法收集2022年6~10月在天津医科大学总医院行VBX支架植入术的27例患者临床资料,对释放成功率、技术成功率、术后30 d临床成功率等治疗结果进行回顾性分析。结果共植入29枚VBX支架,包括治疗狭窄闭塞性病变23处,扩张性病变6处。VBX支架治疗狭窄闭塞病变的器械释放成功率、技术成功率和30 d临床成功率均为100%,治疗扩张性病变的器械释放成功率和30 d临床成功率为100%,技术成功率83.3%。1例肾动脉瘤患者出现内漏,其余患者无狭窄、内漏出现,未发生器械或手术相关的严重不良事件。结论VBX支架应用于既需充分扩张又可能破裂出血造成生命危险的病变部位以及解剖条件适宜的扩张性病变作为主支架以及桥接支架时,均能显示出较好的近期结果。 展开更多
关键词 腔内治疗 动脉瘤 动脉硬化闭塞症 支架移植物
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基于KNN分类算法的微生物白云岩岩相测井综合识别——以四川盆地GM地区灯四段为例
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作者 李昌 王鑫 +1 位作者 冯周 宋连腾 《海相油气地质》 CSCD 北大核心 2023年第4期433-440,共8页
微生物碳酸盐岩的岩-电关系复杂,目前常规测井与电成像测井结合是最有效且精度最高的识别手段。针对人工智能测井岩相识别方法存在的不同维度的测井数据融合难、取心资料有限而训练样本数量不充足的问题,提出基于适应小样本的机器学习... 微生物碳酸盐岩的岩-电关系复杂,目前常规测井与电成像测井结合是最有效且精度最高的识别手段。针对人工智能测井岩相识别方法存在的不同维度的测井数据融合难、取心资料有限而训练样本数量不充足的问题,提出基于适应小样本的机器学习法——K邻近分类算法(KNN),对常规测井与电成像测井分别训练和识别,再将识别结果融合的技术方法。首先,基于岩心资料分别建立岩相分类方案和岩石构造特征分类方案,建立岩心训练样本参数库;然后,基于KNN方法,应用常规测井识别的岩相类型,应用电成像测井识别岩石构造特征类型;最后,根据专家经验对2种识别结果进行融合,获得细分类的岩相类型。以四川盆地GM地区灯影组四段为例,应用上述方法分别识别6种岩相类型和7种岩石构造特征类型,在此基础上根据专家经验融合,最终识别9种细分类的岩相类型。该方法总体识别符合率在85%以上,有效支撑了GM地区灯四段沉积微相的精细研究,推动了该区的勘探和开发工作。该方法发挥了常规测井和电成像测井的优势,能够实现高效率、高精度的岩相测井识别,可推广应用。 展开更多
关键词 微生物碳酸盐岩 KNN算法 常规测井 电成像测井 特征参数 岩相识别
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A Thermoregulatory Flexible Phase Change Nonwoven for All‑Season High‑Efficiency Wearable Thermal Management 被引量:1
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作者 Hanqing Liu feng zhou +9 位作者 Xiaoyu Shi Keyan Sun Yan Kou Pratteek Das Yangeng Li Xinyu Zhang Srikanth Mateti Ying Chen Zhong‑Shuai Wu Quan Shi 《Nano-Micro Letters》 SCIE EI CAS CSCD 2023年第2期259-270,共12页
Phase change materials have a key role for wearable thermal management,but suffer from poor water vapor permeability,low enthalpy value and weak shape stability caused by liquid phase leakage and intrinsic rigidity of... Phase change materials have a key role for wearable thermal management,but suffer from poor water vapor permeability,low enthalpy value and weak shape stability caused by liquid phase leakage and intrinsic rigidity of solid–liquid phase change materials.Herein,we report for the first time a versatile strategy for designed assembly of high-enthalpy flexible phase change nonwovens(GB-PCN)by wet-spinning hybrid grapheneboron nitride(GB)fiber and subsequent impregnating paraffins(e.g.,eicosane,octadecane).As a result,our GB-PCN exhibited an unprecedented enthalpy value of 206.0 J g^(−1),excellent thermal reliability and anti-leakage capacity,superb thermal cycling ability of 97.6%after 1000 cycles,and ultrahigh water vapor permeability(close to the cotton),outperforming the reported PCM films and fibers to date.Notably,the wearable thermal management systems based on GB-PCN for both clothing and face mask were demonstrated,which can maintain the human body at a comfortable temperature range for a significantly long time.Therefore,our results demonstrate huge potential of GB-PCN for human-wearable passive thermal management in real scenarios. 展开更多
关键词 Phase change materials GRAPHENE Boron nitride NONWOVEN Wearable thermal management
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Recent advances and key opportunities on in-plane micro-supercapacitors:From functional microdevices to smart integrated microsystems
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作者 Jieqiong Qin Hongtao Zhang +4 位作者 Zhi Yang Xiao Wang Pratteek Das feng zhou Zhong-Shuai Wu 《Journal of Energy Chemistry》 SCIE EI CAS CSCD 2023年第6期410-431,I0010,共23页
The popularization of portable,implantable and wearable microelectronics has greatly stimulated the rapid development of high-power planar micro-supercapacitors(PMSCs).Particularly,the introduction of new functionalit... The popularization of portable,implantable and wearable microelectronics has greatly stimulated the rapid development of high-power planar micro-supercapacitors(PMSCs).Particularly,the introduction of new functionalities(e.g.,high voltage,flexibility,stretchability,self-healing,electrochromism and photo/thermal response)to PMSCs is essential for building multifunctional PMSCs and their smart selfpowered integrated microsystems.In this review,we summarized the latest advances in PMSCs from various functional microdevices to their smart integrated microsystems.Primarily,the functionalities of PMSCs are characterized by three major factors to emphasize their electrochemical behavior and unique scope of application.These include but are not limited to high-voltage outputs(realized through asymmetric configuration,novel electrolyte and modular integration),mechanical resilience that includes various feats of flexibility or stretchability,and response to stimuli(self-healing,electrochromic,photo-responsive,or thermal-responsive properties).Furthermore,three representative integrated microsystems including energy harvester-PMSC,PMSC-energy consumption,and all-in-one selfpowered microsystems are elaborately overviewed to understand the emerging intelligent interaction models.Finally,the key perspectives,challenges and opportunities of PMSCs for powering smart microelectronics are proposed in brief. 展开更多
关键词 Micro-supercapacitors IN-PLANE Functionalization Integrated microsystem Energy storage
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Epipelagic mesozooplankton communities in the northeastern Indian Ocean off Myanmar during the winter monsoon
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作者 Ping Du Dingyong Zeng +11 位作者 Feilong Lin Sanda Naing Zhibing Jiang Jingjing Zhang Di Tian Qinghe Liu Yuanli Zhu Soe Moe Lwin Wenqi Ye Chenggang Liu Lu Shou feng zhou 《Acta Oceanologica Sinica》 SCIE CAS CSCD 2023年第6期57-69,共13页
The northern Andaman Sea off Myanmar is one of the relatively high productive regions in the Indian Ocean.The abundance,biomass and species composition of mesozooplankton and their relationships with environmental var... The northern Andaman Sea off Myanmar is one of the relatively high productive regions in the Indian Ocean.The abundance,biomass and species composition of mesozooplankton and their relationships with environmental variables in the epipelagic zone(~200 m)were studied for the first time during the Sino-Myanmar joint cruise(February 2020).The mean abundance and biomass of mesozooplankton were(1916.7±1192.9)ind./m3and(17.8±7.9)mg/m3,respectively.A total of 213 species(taxa)were identified from all samples.The omnivorous Cyclopoida Oncaea venusta and Oithona spp.were the top two dominant taxa.Three mesozooplankton communities were determined via cluster analysis:the open ocean in the Andaman Sea and the Bay of Bengal(Group A),the transition zone across the Preparis Channel(Group B),and nearshore water off the Ayeyarwady Delta and along the Tanintharyi Coast(Group C).Variation partitioning analysis revealed that the interaction of physical and biological factors explained 98.8%of mesozooplankton community spatial variation,and redundancy analysis revealed that column mean chlorophyll a concentration(CMCHLA)was the most important explanatory variable(43.1%).The abundance and biomass were significantly higher in Group C,the same as CMCHLA and column mean temperature(CMT)and in contrast to salinity,and CMT was the dominant factor.Significant taxon spatial variations were controlled by CMCHLA,salinity and temperature.This study suggested that mesozooplankton spatial variation was mainly regulated by physical processes through their effects on CMCHLA.The physical processes were simultaneously affected by heat loss differences,freshwater influx,eddies and depth. 展开更多
关键词 MESOZOOPLANKTON Myanmar epipelagic zone physical processes water column mean chlorophyll a
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动态场景下基于实例分割和三维重建的多物体单目SLAM
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作者 冯洲 续欣莹 +2 位作者 郑宇轩 程兰 李鹏越 《仪器仪表学报》 EI CAS CSCD 北大核心 2023年第8期51-62,共12页
针对大多数SLAM系统在动态环境下相机位姿估计不准确与环境语义信息利用不充分的问题,提出一种基于实例分割的关键帧检测和贝叶斯动态特征概率传播的动态物体检测算法,并对环境中存在的静态物体三维重建,以此构建一个动态环境下的多物... 针对大多数SLAM系统在动态环境下相机位姿估计不准确与环境语义信息利用不充分的问题,提出一种基于实例分割的关键帧检测和贝叶斯动态特征概率传播的动态物体检测算法,并对环境中存在的静态物体三维重建,以此构建一个动态环境下的多物体单目SLAM系统。该系统对关键帧输入图像进行实例分割与特征提取,获取潜在运动物体特征点集合与静态物体特征点集合;利用非运动物体特征点集合获取帧间位姿变换,普通帧利用贝叶斯对动静态特征点进行概率传播,利用静态特征点集实现对相机位姿的精准估计;在关键帧中对静态物体进行联合数据关联,数据充足后进行多物体三维重建,构建多物体语义地图,最终实现多物体单目SLAM。本文在TUM与Boon公开数据集上的实验结果表明,在动态场景下,相较于ORB-SLAM2算法,绝对位姿误差的均方根误差平均降低54.1%和58.2%。 展开更多
关键词 多物体单目SLAM 动态场景 实例分割 位姿估计 三维重建
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Intestinal barrier in inflammatory bowel disease:A bibliometric and knowledge-map analysis
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作者 feng zhou Nan-Zhen Wu +1 位作者 Yong Xie Xiao-Jiang zhou 《World Journal of Gastroenterology》 SCIE CAS 2023年第36期5254-5267,共14页
BACKGROUND Barrier surfaces composed of specialized epithelial cells separate the host body from the external environment,and are essential for maintaining proper intestinal physiologic and immune homeostasis.AIM To e... BACKGROUND Barrier surfaces composed of specialized epithelial cells separate the host body from the external environment,and are essential for maintaining proper intestinal physiologic and immune homeostasis.AIM To explore the development trends and research hotspots of intestinal barrier research in inflammatory bowel disease(IBD).METHODS The publications related to the intestinal barrier in IBD were obtained from the Web of Science Core Collection database.Bibliometric analysis and visualization were conducted using VOSviewer,CiteSpace and R software.RESULTS A total of 4482 articles published between 2002 and 2022 were identified.The United States is dominant in intestinal barrier research,whereas the University of Chicago is the most active institution.Jerrold from Harvard Medical School was the most productive authors with the most citations.The journals Inflammatory Bowel Disease and Gastroenterology have made significant contributions in this field.The keywords appearing at high frequency related to the intestinal barrier in IBD were detected,including nuclear factor kappa B,tumor necrosis factor-α,apoptosis,oxidative stress and probiotics.Among them,antioxidants,Akkermansia muciniphila,nanoparticles,short-chain fatty acids and extracellular vesicles have received growing interest in recent research.CONCLUSION The intestinal barrier field is developing rapidly with extensive cooperation.Targeting the gut microbiota and dietary metabolism to regulate the intestinal barrier has shown promising prospective applications and has generated broad interest.The importance of the intestinal barrier in IBD is gradually being fully recognized,providing a new therapeutic perspective for improving inflammation and prognosis. 展开更多
关键词 Intestinal barrier Inflammatory bowel disease BIBLIOMETRICS VISUALIZATION HOTSPOTS
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Observed characteristics of flow,water mass,and turbulent mixing in the Preparis Channel
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作者 Ruijie Ye feng zhou +7 位作者 Xiao Ma Dingyong Zeng Feilong Lin Hongliang Li Chenggang Liu Soe Moe Lwin Hlaing Swe Win Soe Pyae Aung 《Acta Oceanologica Sinica》 SCIE CAS CSCD 2023年第2期83-93,共11页
Preparis Channel is the very important exchange path of energy and materials between the northern Bay of Bengal and Andaman Sea(AS).A set of hydrographic measurements,a microstructure profiler,and a deep mooring were ... Preparis Channel is the very important exchange path of energy and materials between the northern Bay of Bengal and Andaman Sea(AS).A set of hydrographic measurements,a microstructure profiler,and a deep mooring were used to determine the characteristics of water masses,turbulent mixing,and flows in the Preparis Channel.The unprecedented short-term mooring data reveal that a deep current in the deep narrow passage(below 400 m)of the Preparis Channel flows toward the Bay of Bengal(BoB)with a mean along-stream velocity of 25.26 cm/s at depth of 540 m;above the deep current,there are a relatively weak current flows toward the AS with a mean along-stream velocity of 15.46 cm/s between 500 m and 520 m,and another weak current flows toward the BoB between 430 m and 500 m.Thus,a sandwiched vertical structure of deep currents(below 400 m)is present in the Preparis Channel.The volume transport below 400 m is 0.06 Sv(1 Sv=106 m^(3)/s)from the AS to the BoB.In the upper layer(shallower than 300 m),the sea water of the AS is relatively warmer and fresher than that in the BoB,indicating a strong exchange through the channel.Microstructure profiler observations reveal that the turbulent diffusivity in the upper layer of the Preparis Channel reaches O(10−4 m^(2)/s),one order larger than that in the interior of the BoB and over the continental slope of the northern AS.We speculate that energetic high-mode internal tides in the Preparis Channel contribute to elevated turbulent mixing.In addition,a local“hotspot”of turbidity is identified at the deep mooring site,at depth of about 100 m,which corresponds to the location of elevated turbulent mixing in the Preparis Channel. 展开更多
关键词 deep flow turbulent mixing water mass Preparis Channel
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α螺旋结构影响蛋白质稳定性的模拟研究
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作者 金承昊 冯宙 姜舟婷 《中国计量大学学报》 2023年第2期265-270,共6页
目的:研究蛋白质二级结构中α螺旋的比例对蛋白质三级结构的影响。方法:构建不同的蛋白质链模型,以α螺旋结构占比的不同对体系进行区分并采用分子动力学模拟的方法进行研究。结果:以不同比例α螺旋结构的蛋白质链作为样本,研究其结构... 目的:研究蛋白质二级结构中α螺旋的比例对蛋白质三级结构的影响。方法:构建不同的蛋白质链模型,以α螺旋结构占比的不同对体系进行区分并采用分子动力学模拟的方法进行研究。结果:以不同比例α螺旋结构的蛋白质链作为样本,研究其结构的稳定性以及体系的能量。结果表明,体系的键伸缩能和键弯曲能几乎不随蛋白质链中α螺旋结构比例的变化而变化,范德华能受α螺旋结构占比的影响较大,α螺旋占比大的蛋白质链其体系范德华能减小。同时我们发现在该温度(400 K)下,α螺旋结构占比低的蛋白质链中,容易发生α螺旋结构解旋现象,而α螺旋结构占比高的蛋白质链中,部分连接处的非α螺旋结构反而会转变成α螺旋结构。通过分析组成蛋白质链的氨基酸残基的均方根偏差和均方根涨落值可以发现蛋白质链中含α螺旋结构的比例越高,其结构稳定性越强,柔性减弱。结论:这些研究成果呈现α螺旋对蛋白质整体结构的影响,也为其结构转变的动力学行为研究提供理论依据。 展开更多
关键词 分子动力学模拟 蛋白质 结构稳定性 α螺旋结构
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