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China Ocean Engineering 2020年第5期34卷 631-640页

作者： YAN zhe-ping WU Yi liu Yi-bo REN Hong-liang DU Xue College of Automation Harbin Engineering UniversityHarbin 150000China Department of Biomedical Engineering National University of Singapore119007Singapore Systems Engineering Research Institute Beijing 100094China

A consensus algorithm proposed in the paper is applied to tackle remarkable problems of unmeasurable velocities,the environmental disturbances, and the limited communication environment for the multiple unmanned underwater vehicles(multi-UUVs). Firstly, for a complex nonlinear and coupled model of the unmanned underwater vehicle(UUV), a technique of feedback linearization is developed to transform the nonlinear UUV model into a secondorder integral UUV model. Secondly, to address the problem of the unavailable velocity information and environmental disturbances for the multi-UUVs system, we design a distributed extended state observer(DESO) to estimate the unmeasurable velocities and environmental disturbances using the relative position information. Finally,we propose a protocol based on the estimation information from the DESO and demonstrate that the multi-UUVs system with the switching directed topologies under the protocol can reach consensus asymptotically. The theoretical result proposed in the literature is verified by one numerical example.

关键词： multiple unmanned underwater vehicles feedback linearization distributed extended state observe switching directed topologies

End-to-end verifiable electronic voting scheme of blockchain based on random linear block code

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High Technology Letters 2020年第1期26卷 25-33页

作者： liu Ting Cui zhe Pu Hongquan Peng Xingyi Chengdu Institute of Computer Applications Chinese Academy of SciencesChengdu 610041P.R.China School of Computer and Control Engineering University of Chinese Academy of SciencesBeijing 100049P.R.China Guangxi Key Laboratory of Hybrid Computation and IC Design Analysis Nanning 530006P.R.China

Blockchain is an emerging decentralized technology of electronic *** current main consensus protocols are not flexible enough to manage the distributed blockchain nodes to achieve high efficiency of *** practical implementation,the consensus based on random linear block code(RLBC)is proposed and applied to blockchain voting *** with achieving the record correctness and consistency among all nodes,the consensus method indicates the active and inactive consensus *** ability can assist the management of consensus nodes and restrain the generating of chain *** achieve end-to-end verifiability,cast-or-audit and randomized partial checking(RPC)are used in the proposed *** voter can verify the high probability of correctness in ballot encryption and *** experiments illustrate that the efficiency of proposed consensus is suitable for *** proposed electronic voting scheme is adapted to practical implementation of voting.

关键词： random linear block code(RLBC) electronic voting(e-voting) blockchain consensus end-to-end verifiable

索氏与超声法提取PM_(2.5)中多环芳烃的比较

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环境卫生学杂志 2015年第2期5卷 160-164页

作者：常君瑞李娜徐春雨刘喆吴亚西中国疾病预防控制中心环境与健康相关产品安全所

目的比较索氏提取法与超声提取法对颗粒物中苯并[b]荧蒽、苯并[k]荧蒽、苯并[a]芘、二苯并[a,h]蒽、茚并[1,2,3-c,d]芘、苯并[g,h,i]苝的提取效果。方法对加标的空白滤膜以及采样滤膜用索氏提取法及超声提取法进行处理、用高效液相色谱... 详细信息

目的比较索氏提取法与超声提取法对颗粒物中苯并[b]荧蒽、苯并[k]荧蒽、苯并[a]芘、二苯并[a,h]蒽、茚并[1,2,3-c,d]芘、苯并[g,h,i]苝的提取效果。方法对加标的空白滤膜以及采样滤膜用索氏提取法及超声提取法进行处理、用高效液相色谱—荧光检测器测定,计算两种样品前处理方法的相对标准偏差(RSD)及加标回收率并进行比较。结果索氏提取法与超声提取法的相对标准偏差分别为3.6%、2.9%。索氏提取法和超声提取法对空白滤膜的加标回收率分别为91.7%和90.3%,对6种物质回收率的标准差分别为18.5%、2.8%,索氏提取法与超声提取法对采样滤膜的加标回收率分别为89.0%、83.3%,回收率的标准差分别为1.7%、3.1%。在实际样品测定的比较中,两种样品前处理方法取得了相近的结果。结论索氏提取法处理步骤多,影响结果的因素较多;超声提取法操作简便,操作过程对结果的影响较小,结果比较稳定。超声提取法是一种比较实用、快速的样品前处理方法。

关键词：索氏提取法超声提取法多环芳烃 PM2.5 比较

空气污染物暴露相关出行行为调查方法一致性研究

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中华预防医学杂志 2018年第6期52卷 608-614页

作者：李娜刘喆李韵谱李宁王秦吴亚西杨一兵徐春雨徐东群中国疾病预防控制中心环境与健康相关产品安全所北京100021 南京市江宁区疾病预防控制中心

目的为提高空气污染暴露评估的准确性,开展出行信息调查,比较日志记录与全球定位系统（GPS）法调查人群出行信息的一致性,探讨造成两种方法调查结果不一致的原因.方法于2015年7—9月及11—12月,以南京市江宁区33名退休人群作为研究对... 详细信息

目的为提高空气污染暴露评估的准确性,开展出行信息调查,比较日志记录与全球定位系统（GPS）法调查人群出行信息的一致性,探讨造成两种方法调查结果不一致的原因.方法于2015年7—9月及11—12月,以南京市江宁区33名退休人群作为研究对象,同时采用日志法及GPS法进行为期5 d的出行行为调查.使用Google Earth进行GPS数据的提取和展示,计算数据的完整性,并依据时间和位置与日志记录进行匹配分析,计算两种方法一致率;采用χ^2检验分析不同行程特征对方法漏报、误报率的影响.结果两种方法共监测到1087条出行记录（GPS法912条,日志法909条）,其中7.3％（79/1087）的行程仅被GPS记录,11.8％（128/1087）的行程仅被日志法记录.而在两种方法同时监测到的行程记录（880/1087）中,86.7％（763/880）匹配,13.3％（117/880）不匹配;对匹配的行程单独分析发现,日志法记录的行程持续时间大于GPS法（P〈0.001）,差值中位数（四分位数间距）为2.0（6.0）min,与GPS法相比,日志法高估了25.0％的行程持续时间;日志法和GPS法的行程准确率分别为84.8％（903/1065）和86.9％（925/1065）,两种方法均倾向于漏报误报持续时间≤5 min的行程,其中日志法对≤5 min的行程漏报误报率（21.7％）远高于〉30 min行程（3.2％）的漏报误报率.不同交通方式的出行监测准确率差异存在统计学意义（P〈0.05）,日志法对机动车出行监测准确率最低（69.3％,133/192）,而GPS法对骑车（91.9％,136/148）和机动车（89.6％,172/192）出行监测的准确性均较高.造成日志法漏报、误报的主要原因为忘记记录、主观上不愿意报告和没有将采用不同交通方式的行程分别记录;而造成GPS法漏报、误报的主要原因为未携带GPS设备、GPS信号质量不良和因搜索信号造成的时间延迟.结论日志法及GPS法总体上具有较好的一致性,但均存在一定的漏报和误报等问题,将两种方法结合使用将有助于提高监测结果的准确性.

关键词：环境暴露空气污染时间-活动模式 GPS

外源水杨酸对低温胁迫下玉米幼苗生长及生理特性的影响

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江苏农业学报 2018年第4期34卷 726-734页

作者：孙玉珺秦东玲伊凡宫磊刘哲吕金莹杨慧张平徐密林张倩杨德光东北农业大学农学院黑龙江哈尔滨150030

为探究外源水杨酸(SA)对低温胁迫下玉米幼苗生长及生理特性的影响,以抗冷玉米自交系Kr701和冷敏感玉米自交系黑8834为材料,采用外源叶面喷施5个不同质量浓度(0 mg/L、25 mg/L、50 mg/L、100 mg/L和150 mg/L)SA的方法,分析了低温胁迫下... 详细信息

为探究外源水杨酸(SA)对低温胁迫下玉米幼苗生长及生理特性的影响,以抗冷玉米自交系Kr701和冷敏感玉米自交系黑8834为材料,采用外源叶面喷施5个不同质量浓度(0 mg/L、25 mg/L、50 mg/L、100 mg/L和150 mg/L)SA的方法,分析了低温胁迫下玉米幼苗的农艺性状(株高、根长、地上部干质量及地下部干质量)和生理生化指标(相对含水量、相对电导率、净光合速率、丙二醛含量、超氧化物歧化酶和过氧化物酶活性)的变化。结果表明,喷施低浓度SA能有效减轻低温对玉米幼苗生长的抑制程度。在50 mg/L处理时效果最显著,主要表现在幼苗地上部干质量、地下部干质量、相对含水量、净光合速率、超氧化物歧化酶和过氧化物酶活性的增加;相对电导率、MDA含量的降低;在低温胁迫下,与低温对照比较,50 mg/L水杨酸处理的玉米自交系Kr701和黑8834株高分别增加17.3%、18.3%,相对含水量分别提高58.1%、66.3%,过氧化物酶活性分别增加35.7%、54.4%,相对电导率分别下降51.2%、58.6%。

关键词：玉米低温胁迫水杨酸生长生理特性

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强迫障碍与惊恐障碍注意功能的对照研究

临床精神医学杂志 2013年第2期23卷 79-81页

作者：吴东辉胡赤怡林雄标刘哲宁深圳市精神卫生中心老年精神科 518020 深圳市心理健康实验室长沙中南工业大学湘雅二院精神卫生

目的:探讨强迫障碍患者与惊恐障碍患者注意功能的特征。方法:采用倒行掩蔽测验(BMT)和连续操作测验(CPT)分别对强迫障碍患者、惊恐障碍患者和健康对照者3组各38例评估其注意的激活度、选择性注意和维持注意功能,以Maudsley强迫障碍症状... 详细信息

目的:探讨强迫障碍患者与惊恐障碍患者注意功能的特征。方法:采用倒行掩蔽测验(BMT)和连续操作测验(CPT)分别对强迫障碍患者、惊恐障碍患者和健康对照者3组各38例评估其注意的激活度、选择性注意和维持注意功能,以Maudsley强迫障碍症状问卷和Yale-Brown强迫量表对强迫患者评定其强迫症状严重程度。结果:掩蔽时间分别为30ms和50ms时,强迫障碍患者组的BMT正确数显著低于正常对照组(P均<0.05);无掩蔽时,两组BMT正确数差异无统计学意义;不同情境下,两组CPT正确数之间的差异无统计学意义。惊恐障碍患者在不同掩蔽的BMT正确数、不同情境下的CPT正确数与对照组相比,均无明显差异。掩蔽时间为30ms和50ms,强迫障碍患者组的BMT正确数[(5.6±2.5)和(9.2±4.1)]显著低于惊恐障碍组[(7.6±4.2)和(12.1±4.3)],(P均<0.05);而无掩蔽时,两组BMT正确数以及3种情境下的CPT正确数差异无统计学意义。强迫障碍患者的BMT正确数与Maudsley强迫障碍状问卷、Yale-Brown强迫行为和强迫思维量表的得分无显著相关性。结论:强迫障碍患者可能存在明显的选择性注意受损,而惊恐患者的注意功能无明显受损。

关键词：强迫障碍惊恐障碍倒行掩蔽测验连续操作测验

深度处理生物活性炭对微量污染物的吸附及解吸与颗粒活性炭滤料的更换周期

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净水技术 2021年第5期40卷 64-68页

作者：吴声达刘哲陈朝湘陈妙玲吴婉华广州市自来水有限公司广东广州510000

华南某O3-BAC工艺大型水厂GAC使用1年后碘吸附值下降39%,使用5年后下降92%。以炭柱试验装置模拟该水厂,试验中投加苯酚、铊等污染物。结果表明:不同年份活性炭对微量酚类有机污染源处理能力较高;新炭对重金属铊的去除率较一年炭和五年炭... 详细信息

华南某O3-BAC工艺大型水厂GAC使用1年后碘吸附值下降39%,使用5年后下降92%。以炭柱试验装置模拟该水厂,试验中投加苯酚、铊等污染物。结果表明:不同年份活性炭对微量酚类有机污染源处理能力较高;新炭对重金属铊的去除率较一年炭和五年炭差,十年炭去除率最低。不同pH的进水对不同年份炭滤料进行动态解吸试验,污染物析出量可忽略。结合炭滤料性能指标,建议6~8年可计划分段更换活性炭滤料及垫层。

关键词：颗粒活性炭生物活性炭吸附解吸更换周期微量污染物

Phloroglucinol derivative compound 21 attenuates cuprizoneinduced multiple sclerosis mice through promoting remyelination and inhibiting neuroinflammation

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Science China(Life Sciences) 2020年第6期63卷 905-914页

作者： zhe Zhao Xiu-qi Bao Zihong Zhang Hui liu Dan Zhang State Key Laboratory of Bioactive Substrate and Function of Natural Medicine Institute of Materia MedicaChinese Academy of Medical Sciences and Peking Union Medical CollegeBeijing 100050China

Multiple sclerosis(MS) is a chronic autoimmune demyelinating disease in the central nervous system. The myelin loss is mainly caused by dysfunction of oligodendrocytes and inflammatory responses of microglia and astrocytes further aggravate the demyelination. Current therapies for MS focus on suppressing the overactivated immune response but cannot halt the disease progress, so effective drugs are urgently needed. Compound 21 is a phloroglucinol derivative that has been proved to have an outstanding anti-inflammatory effect. The purpose of the present study is to investigate whether this novel compound is effective in MS. The cuprizone-induced model was used in this study to mimic the pathological progress of MS. The results showed that Compound 21 significantly improved the neurological dysfunction and motor coordination impairment. Luxol Fast Blue staining and myelin basic protein immunostaining demonstrated that Compound 21 remarkably promoted remyelination. In addition,Compound 21 significantly promoted oligodendrocytes differentiation. Furthermore, we found that Compound 21 decreased microglia and astrocytes activities and the subsequent neuroinflammatory response, indicating that the anti-inflammatory effect of Compound 21 was also involved in its neuro-protection. All the data prove that Compound 21 exerts protective effect on MS through promoting remyelination and suppressing neuroinflammation, indicating that Compound 21 might be a potential drug candidate for MS treatment.

关键词： multiple sclerosis oligodendrocytes demyelination microglia astrocytes

Salient Object Detection Based on a Novel Combination Framework Using the Perceptual Matching and Subjective-Objective Mapping Technologies

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Journal of Beijing Institute of Technology 2023年第1期32卷 95-106页

作者： Jian Han Jialu Li Meng liu zhe Ren Zhimin Cao Xingbin liu School of Physics and Electronic Engineering Northeast Petroleum UniversityDaqing 163318China

The integrity and fineness characterization of non-connected regions and contours is a major challenge for existing salient object *** key to address is how to make full use of the subjective and objective structural information obtained in different ***,by simulating the human visual mechanism,this paper proposes a novel multi-decoder matching correction network and subjective structural ***,the loss pays different attentions to the foreground,boundary,and background of ground truth map in a top-down *** the perceived saliency is mapped to the corresponding objective structure of the prediction map,which is extracted in a bottom-up ***,multi-level salient features can be effectively detected with the loss as *** then,through the mapping of improved binary cross entropy loss,the differences between salient regions and objects are checked to pay attention to the error prone region to achieve excellent error ***,through tracking the identifying feature horizontally and vertically,the subjective and objective interaction is *** experiments on five benchmark datasets demonstrate that compared with 12 state-of-the-art methods,the algorithm has higher recall and precision,less error and strong robustness and generalization ability,and can predict complete and refined saliency maps.

关键词： salient object detection subjective-objective mapping perceptional separation and matching error sensitivity non-connected region detection

CO_(2)在栗子壳基碳材料上的吸附动力学及热力学研究

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应用化工 2023年第2期52卷 445-450页

作者：刘新辙陈娟张明阳户正雨贤帅飞唐明璇张晨晨山东建筑大学热能工程学院山东济南250101

由栗子壳制备栗子壳碳和栗子壳活性炭进行CO_(2)吸附,对实验数据进行动力学模型与热力学模型拟合,计算得到动力学及热力学参数,探讨栗子壳基碳材料对CO_(2)的吸附机理。结果表明,栗子壳碳和栗子壳活性炭对CO_(2)的吸附符合准一阶动力学... 详细信息

由栗子壳制备栗子壳碳和栗子壳活性炭进行CO_(2)吸附,对实验数据进行动力学模型与热力学模型拟合,计算得到动力学及热力学参数,探讨栗子壳基碳材料对CO_(2)的吸附机理。结果表明,栗子壳碳和栗子壳活性炭对CO_(2)的吸附符合准一阶动力学模型,298 K下吸附自由能(ΔG)、吸附热(ΔH)和吸附熵(ΔS)均小于0,表明该吸附过程是一个放热的混乱度降低的自发过程,吸附以物理吸附为主,吸附过程主要发生在外表面单分子层。

关键词：栗子壳基碳材料 CO_(2)吸附动力学热力学