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Sensitivity of P300 auditory event-related potentials for assessing cognitive impairment in elderly type 2 diabetic patients 被引量:2
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作者 Hong Yang Junhong She Xianfu Lu Rihong Peng 《Neural Regeneration Research》 SCIE CAS CSCD 2008年第8期894-898,共5页
BACKGROUND:In previous studies, cognitive function in elderly type 2 diabetic patients was evaluated by psychometric tests. These studies have confirmed that P300 event-related potential is an objective way of assess... BACKGROUND:In previous studies, cognitive function in elderly type 2 diabetic patients was evaluated by psychometric tests. These studies have confirmed that P300 event-related potential is an objective way of assessing cognitive function. OBJECTIVE: To analyze the objectivity of P300 for assessment of cognitive function in elderly type 2 diabetic patients. DESIGN, TIME AND SETTING: This case-control experiment was performed at the Department of Endocrinology of the Fourth Affiliated Hospital, Guangxi Medical University from January 2004 to December 2006. PARTICIPANTS: Seventy-two patients (38 males and 34 females) with type 2 diabetes mellitus were enrolled in this study. The patients were divided according to those with diabetes alone (diabetes alone group) (n=38) and those with diabetes and cerebral ischemia (diabetes and cerebral ischemia group) (n=34). A further 31 healthy individuals (16 males and 15 females), who received health examinations over the same period, were included as normal controls (normal control group). METHODS: All subjects were assessed by Mini-Mental State Examination (MMSE). Abnormalities in cognitive functions were identified by analyzing the auditory P300 event-related potentials. MAIN OUTCOME MEASURES: Auditory event-related potentials and MMSE scores. Multiple linear regression analysis was conducted using the "enter method" with the 72 elderly patients with type 2 diabetes mellitus. P3 latency, P3 amplitude and N2 latency served as dependent variables. Age, sex, education, course of the disease, glycosylated hemoglobin, and ischemic brain damage were used as independent variables. RESULTS: No significant difference in scores of MMSE was detected between the diabetes alone and normal control groups (P 〉 0.05). MMSE score was significantly lower in the diabetes and cerebral ischemia group (P 〈 0.01) than in the normal control group. N2 and P3 latencies of auditory event-related potential were significantly longer, and P3 amplitude was significantly lower in the diabetes alone and diabetes and cerebral ischemia groups (P 〈 0.01) than in the normal control group. N2 and P3 latencies were significantly longer in the diabetes and cerebral ischemia group than in the diabetes alone group (P 〈 0.01), but amplitude was not significantly different. N2 and P3 latencies were negatively correlated with MMSE score in elderly type 2 diabetic patients (r=–0.421, –0.604; both P 〈 0.01). P3 amplitude was positively related to the score of MMSE (r =0.517; P 〈 0.01). P3 latency was positively associated with age, course of disease, glycosylated hemoglobin and ischemic brain damage in elderly type 2 diabetic patients (t=2.186 to 3.490; all P 〈 0.05). P3 amplitude was negatively correlated with age, course of disease and glycosylated hemoglobin (t=–2.220, –2.491, and –2.024, respectively; all P 〈 0.05). N2 latency was positively correlated with age, course of disease and ischemic brain damage (t=2.946, 2.511, and 2.331, respectively; P 〈 0.05). CONCLUSION: The course of disease, glycosylated hemoglobin and ischemic brain damage are key influential factors for cognitive impairment in elderly type 2 diabetic patients. The P300 event-related potential is a sensitive index for objective assessment of cognitive impairment in elderly diabetic patients. 展开更多
关键词 ELDERLY type 2 diabetes mellitus cognitive impairment aevent-related potential P300
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Auditory P300 as an Indicator in Effectiveness of Robot-Assisted Lower Limb Rehabilitation Training among Hemiplegic Patients after Ischemic Stroke 被引量:3
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作者 Yaning Zhao Zhengwei Hao Jianmin Li 《Open Journal of Therapy and Rehabilitation》 2014年第2期76-85,共10页
Background: Robot-assisted lower limb rehabilitation training in early stage could improve the limb function among hemiplegic patients caused by ischemic stroke. P300 potential changes have importantly clinical value ... Background: Robot-assisted lower limb rehabilitation training in early stage could improve the limb function among hemiplegic patients caused by ischemic stroke. P300 potential changes have importantly clinical value for evaluating the improvement in nerve function during the training as one of the objective targets. Methods: Sixty hemiplegic patients after stroke were randomly divided into a Lokomat group (30 cases) and a control group (30 cases). The Lokomat group received Lokomat rehabilitation while the control group only received traditional rehabilitation. The gait parameters and the balance ability were evaluated by the K421GAITRite analysis system and the Berg Balance Scale (BBS);ERP components including N100, N200, P200 and P300 potential were evaluated by a muscle electric inducing potentiometer. Results: There were no significant differences in BBS and gait parameters (P > 0.05), as well as in amplitude and incubation periods (IP) (P > 0.05) between the two groups before training. After 8 weeks treatment, the total (48.88 ± 3.68), static (26.40 ± 3.14) and dynamic (22.64 ± 3.68) balance scores improved significantly;the pace (59.22 ± 4.67), stride length (19.04 ± 2.24), feet wide (98.02 ± 7.97) and walking velocity (84.86 ± 9.88) and IP of N200 and P300 shortened obviously and P300 amplitude increased significantly in robot group (P < 0.05). Conclusion: This demonstrated that robot-assisted lower limb rehabilitation training in early stage could improve the limb function among hemiplegic patients caused by ischemic stroke. P300 may be considered as an indicator of neurological function improvement and effective robot-assisted lower limb rehabilitation training. 展开更多
关键词 Lokomat Lower LIMB Gait Training Rehabilitation Robot Cerebral INFaRCTION HEMIPLEGIC P300
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上瘾之品 MERCEDES-BENZ C300 AVANTGARDE ESTATE
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《世界汽车》 2011年第3期62-67,共6页
曾在一次聚会中,我摆出"低调做人"的观点,却遭到朋友反对。是的,在这个宣扬个性的时代,人们不需要自我压抑,高调是一种生活品位。在西方国家,汽车生活是有内涵的,商用、休旅等不同的场合,人们会开着不同功能的车型,人们注重品位和高... 曾在一次聚会中,我摆出"低调做人"的观点,却遭到朋友反对。是的,在这个宣扬个性的时代,人们不需要自我压抑,高调是一种生活品位。在西方国家,汽车生活是有内涵的,商用、休旅等不同的场合,人们会开着不同功能的车型,人们注重品位和高质量的生活。 展开更多
关键词 C300 生活品位 西方国家 商用
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颜值与品质俱佳!——光阳全新CT300 ABS版全网首测
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作者 《摩托车信息》 2019年第8期40-47,共8页
在2019北京国际摩托车展览会上,光阳摩托一口气推出了多款重磅车型,吸引了众多摩迷驻足观看,现场展示的CT300 ABS版(以下简称CT300)更是吸引了无数摩迷的眼球。CT300版是CT250(暂无ABS版)的后续升级车型,CT250是光阳在年初推出的国内首... 在2019北京国际摩托车展览会上,光阳摩托一口气推出了多款重磅车型,吸引了众多摩迷驻足观看,现场展示的CT300 ABS版(以下简称CT300)更是吸引了无数摩迷的眼球。CT300版是CT250(暂无ABS版)的后续升级车型,CT250是光阳在年初推出的国内首款250mL级别的平脚踏板车,20280元的售价,超高的性价比,加上光阳的口碑,CT250上市后立即成为了同级车型的有力竞争对手,市场硝烟弥漫。那么,作为后续升级车型的CT300又会有哪些方面的亮点呢? 展开更多
关键词 CT300 aBS 双活塞
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光阳全新赛艇CT300 ABS城市摩旅版及多款新品发布
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作者 《摩托车信息》 2019年第6期26-29,共4页
5月11日,在北京举行的2019北京国际摩托车展览会上,光阳摩托(KYMCO)以'您的出行无与伦比'为主题参加了本次展会,并在展会上举行了盛大的新品发布会,一口气推出了两款电摩及5款国Ⅳ踏板摩托,可谓大气势,大阵仗。本次发布会,光阳... 5月11日,在北京举行的2019北京国际摩托车展览会上,光阳摩托(KYMCO)以'您的出行无与伦比'为主题参加了本次展会,并在展会上举行了盛大的新品发布会,一口气推出了两款电摩及5款国Ⅳ踏板摩托,可谓大气势,大阵仗。本次发布会,光阳推出的五款国Ⅳ摩托新品分别为:全新赛艇CT300ABS版城市摩旅车、赛艇S400ABS国Ⅳ版以及赛艇250ABS版。 展开更多
关键词 纪念版 CT300 aBS aBS
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Fujitsu DYNA MO 1300 AI
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《电子测试》 2001年第2期54-54,共1页
这款产品运用了设置简便、普及率高的IDE接口,而且在性能表现方面,也都维持在一定的水准之上,可以说是一款取得了价格与性能之间平衡点的优良产品。
关键词 Fujitsu/300aI IDE接口 MO机 磁光盘
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Arcam AVR-300 AV功率放大器
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《音响世界》 2004年第8期4-4,共1页
关键词 arcam公司 aVR-300 aV功率放大器 功能
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姜黄素通过抑制乙酰转移酶P300表达促进HeLa细胞凋亡 被引量:1
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作者 赵行宇 丁思源 +1 位作者 何奇 张巍 《中国病理生理杂志》 CAS CSCD 北大核心 2024年第7期1197-1204,共8页
目的:探讨姜黄素(Cur)通过下调HeLa细胞腺病毒E1A相关300 kD蛋白(P300)调控HeLa细胞的活力及凋亡。方法:将对数生长期的HeLa细胞分别采用20、40、60和80μmol/L Cur处理,并以未处理组细胞作为对照,用CCK-8法检测细胞活力;选取20和40μmo... 目的:探讨姜黄素(Cur)通过下调HeLa细胞腺病毒E1A相关300 kD蛋白(P300)调控HeLa细胞的活力及凋亡。方法:将对数生长期的HeLa细胞分别采用20、40、60和80μmol/L Cur处理,并以未处理组细胞作为对照,用CCK-8法检测细胞活力;选取20和40μmol/L Cur处理细胞,以流式细胞术检测细胞凋亡,RT-qPCR、Western blot法检测E6基因的mRNA和蛋白表达及凋亡相关蛋白、P300和组蛋白的表达;构建沉默质粒shE6和阴性对照质粒shNC转染HeLa细胞,设置shNC,shNC+Cur(40μmol/L),shE6以及shE6+Cur(40μmol/L)四组,以CCK-8、流式细胞术以及Western blot法分别检测细胞活力、凋亡以及凋亡相关蛋白的表达;构建沉默质粒siP300和阴性对照质粒siNC转染HeLa细胞,RT-PCR、Western blot法分别检测P300的mRNA和蛋白表达、E6的蛋白表达。结果:与未处理组相比,用不同浓度Cur处理HeLa细胞后能显著抑制其活力并可使早期凋亡率增高(P<0.05);Cur处理HeLa细胞后,E6的mRNA及蛋白表达均下调,而敲减E6与未敲减E6的Cur处理组相比,敲减组的早期凋亡率以及促凋亡相关蛋白表达均低于未敲减组(P<0.05);敲减P300后,HeLa细胞中E6蛋白表达降低;而单以Cur处理HeLa细胞后,P300及相关组蛋白表达均下调(P<0.01)。结论:Cur抑制HPV18阳性宫颈癌细胞的活力并促进其凋亡,机制可能与其下调P300而抑制E6蛋白乙酰化有关。 展开更多
关键词 姜黄素 乙酰化 HELa细胞 P300
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A-485通过抑制P300/CBP诱导的H3K18ac/H3K27ac减轻糖尿病肾小管细胞脂质沉积
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作者 孟丽 朱艳 +5 位作者 杨琰 吴婷 任韫卓 杜林珊 曾士洁 杜春阳 《临床与实验病理学杂志》 CAS 北大核心 2024年第5期509-514,共6页
目的观察A-485对糖尿病小鼠肾小管损伤的保护作用及机制。方法将18只雄性C57BL/6J小鼠随机分为对照组、糖尿病肾病(diabetic kidney disease,DKD)组和A-485治疗组。DKD小鼠模型构建采用高脂饲料饲喂8周联合腹腔注射链脲佐菌素5天的方法... 目的观察A-485对糖尿病小鼠肾小管损伤的保护作用及机制。方法将18只雄性C57BL/6J小鼠随机分为对照组、糖尿病肾病(diabetic kidney disease,DKD)组和A-485治疗组。DKD小鼠模型构建采用高脂饲料饲喂8周联合腹腔注射链脲佐菌素5天的方法。随后,A-485治疗组隔日给予1次A-485(10 mg/kg)腹腔注射,共4周。治疗结束后,检测小鼠肾功能、P300酶活性及脂质沉积情况;Western blot法检测SREBP-1、FASN、ACC、ChREBP、P300、CBP、H3K18ac和H3K27ac蛋白的表达水平。结果与对照小鼠相比,DKD小鼠FBG(2.52倍)、BUN(2.89倍)、Scr(2.13倍)及UAE(4.21倍)显著升高(P<0.01);A-485干预能够降低BUN(0.511倍)、Scr(0.636倍)及UAE(0.574倍)的水平(P<0.01)。电镜及油红O染色结果显示,A-485干预抑制糖尿病小鼠肾小管细胞内脂滴形成及SREBP-1(0.544倍)、FASN(0.449倍)、ACC(0.306倍)、ChREBP(0.317倍)蛋白高表达(P<0.01)。同时,A-485干预下调P300酶活性(0.546倍),抑制H3K18ac(0.337倍)和H3K27ac(0.308倍)的表达(P<0.01)。结论A-485能够明显改善糖尿病小鼠肾组织脂代谢紊乱,该作用可能是通过抑制P300诱导的H3K18ac和H3K27ac实现的。 展开更多
关键词 糖尿病肾病 P300/CBP a-485 脂质沉积 乙酰化
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Blockade of CD300A enhances the ability of human NK cells to lyse hematologic malignancies 被引量:1
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作者 Shuangcheng Li Tianci Wang +6 位作者 Xinghui Xiao Xiaodong Zheng Haoyu Sun Rui Sun Hongdi Ma Zhigang Tian Xiaohu Zheng 《Cancer Biology & Medicine》 SCIE CAS CSCD 2024年第4期331-346,共16页
Objective: The human cluster of differentiation(CD)300A, a type-I transmembrane protein with immunoreceptor tyrosine-based inhibitory motifs, was investigated as a potential immune checkpoint for human natural killer(... Objective: The human cluster of differentiation(CD)300A, a type-I transmembrane protein with immunoreceptor tyrosine-based inhibitory motifs, was investigated as a potential immune checkpoint for human natural killer(NK) cells targeting hematologic malignancies(HMs).Methods: We implemented a stimulation system involving the CD300A ligand, phosphatidylserine(PS), exposed to the outer surface of malignant cells. Additionally, we utilized CD300A overexpression, a CD300A blocking system, and a xenotransplantation model to evaluate the impact of CD300A on NK cell efficacy against HMs in in vitro and in vivo settings. Furthermore, we explored the association between CD300A and HM progression in patients.Results: Our findings indicated that PS hampers the function of NK cells. Increased CD300A expression inhibited HM lysis by NK cells. CD300A overexpression shortened the survival of HM-xenografted mice by impairing transplanted NK cells. Blocking PS–CD300A signals with antibodies significantly amplified the expression of lysis function-related proteins and effector cytokines in NK cells, thereby augmenting the ability to lyse HMs. Clinically, heightened CD300A expression correlated with shorter survival and an “exhausted” phenotype of intratumoral NK cells in patients with HMs or solid tumors.Conclusions: These results propose CD300A as a potential target for invigorating NK cell-based treatments against HMs. 展开更多
关键词 NK cell CD300a PHOSPHaTIDYLSERINE immune checkpoint hematologic malignancy
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基于Modbus的GCAN PLC与S7-300通讯系统
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作者 张子航 张秀珩 李岩 《工业控制计算机》 2024年第8期46-48,共3页
使用带有4G网络模块的GCAN PLC与S7-300 PLC进行通讯,实现往复式压缩机的物联网连接。针对S7-300 PLC的CP340通讯模块无法实现Modbus通讯的问题,运用TIA Portal和Open PCS软件编程。采用RS-485根据Modbus RTU的通讯格式,使CP340通讯模... 使用带有4G网络模块的GCAN PLC与S7-300 PLC进行通讯,实现往复式压缩机的物联网连接。针对S7-300 PLC的CP340通讯模块无法实现Modbus通讯的问题,运用TIA Portal和Open PCS软件编程。采用RS-485根据Modbus RTU的通讯格式,使CP340通讯模块实现CRC校验,完成了S7-300 PLC和GCAN PLC的Modbus RTU通讯系统。经过通讯测试,系统运行稳定且CRC校验无误,能实时对压缩机仪表数据进行传输。 展开更多
关键词 S7-300 PLC CP340 GCaN PLC MODBUS
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Image Segmentation-P300 Selector: A Brain–Computer Interface System for Target Selection
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作者 Hang Sun Changsheng Li He Zhang 《Computers, Materials & Continua》 SCIE EI 2024年第5期2505-2522,共18页
Brain–computer interface (BCI) systems, such as the P300 speller, enable patients to express intentions withoutnecessitating extensive training.However, the complexity of operational instructions and the slow pace of... Brain–computer interface (BCI) systems, such as the P300 speller, enable patients to express intentions withoutnecessitating extensive training.However, the complexity of operational instructions and the slow pace of characterspelling pose challenges for some patients. In this paper, an image segmentation P300 selector based on YOLOv7-mask and DeepSORT is proposed. The proposed system utilizes a camera to capture real-world objects forclassification and tracking. By applying predefined stimulation rules and object-specificmasks, the proposed systemtriggers stimuli associated with the objects displayed on the screen, inducing the generation of P300 signals in thepatient’s brain. Its video processing mechanism enables the system to identify the target the patient is focusing oneven if the object is partially obscured, overlapped, moving, or changing in number. The system alters the target’scolor display, thereby conveying the patient’s intentions to caregivers. The data analysis revealed that the selfrecognitionaccuracy of the subjects using this method was between 92% and 100%, and the cross-subject P300recognition precision was 81.9%–92.1%. This means that simple instructions such as “Do not worry, just focuson what you desire” effectively discerned the patient’s intentions using the Image Segmentation-P300 selector. Thisapproach provides cost-effective support and allows patients with communication difficulties to easily express theirneeds. 展开更多
关键词 Brain-computer interface deep learning ELECTROENCEPHaLOGRaM P300 YOLOv7-mask
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IL-17 induces NSCLC cell migration and invasion by elevating MMP19 gene transcription and expression through the interaction of p300-dependent STAT3-K631 acetylation and its Y705-phosphorylation
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作者 WEN GE YA LI +7 位作者 YUTING RUAN NINGXIA WU PEI MA TONGPENG XU YONGQIAN SHU YINGWEI WANG WEN QIU CHENHUI ZHAO 《Oncology Research》 SCIE 2024年第4期625-641,共17页
The cancer cell metastasis is a major death reason for patients with non-small cell lung cancer(NSCLC).Although researchers have disclosed that interleukin 17(IL-17)can increase matrix metalloproteinases(MMPs)inductio... The cancer cell metastasis is a major death reason for patients with non-small cell lung cancer(NSCLC).Although researchers have disclosed that interleukin 17(IL-17)can increase matrix metalloproteinases(MMPs)induction causing NSCLC cell metastasis,the underlying mechanism remains unclear.In the study,we found that IL-17 receptor A(IL-17RA),p300,p-STAT3,Ack-STAT3,and MMP19 were up-regulated both in NSCLC tissues and NSCLC cells stimulated with IL-17.p300,STAT3 and MMP19 overexpression or knockdown could raise or reduce IL-17-induced p-STAT3,Ack-STAT3 and MMP19 level as well as the cell migration and invasion.Mechanism investigation revealed that STAT3 and p300 bound to the same region(−544 to−389 nt)of MMP19 promoter,and p300 could acetylate STAT3-K631 elevating STAT3 transcriptional activity,p-STAT3 or MMP19 expression and the cell mobility exposed to IL-17.Meanwhile,p300-mediated STAT3-K631 acetylation and its Y705-phosphorylation could interact,synergistically facilitating MMP19 gene transcription and enhancing cell migration and invasion.Besides,the animal experiments exhibited that the nude mice inoculated with NSCLC cells by silencing p300,STAT3 or MMP19 gene plus IL-17 treatment,the nodule number,and MMP19,Ack-STAT3,or p-STAT3 production in the lung metastatic nodules were all alleviated.Collectively,these outcomes uncover that IL-17-triggered NSCLC metastasis involves up-regulating MMP19 expression via the interaction of STAT3-K631 acetylation by p300 and its Y705-phosphorylation,which provides a new mechanistic insight and potential strategy for NSCLC metastasis and therapy. 展开更多
关键词 NSCLC cell migration and invasion IL-17 P300 STaT3 MMP19 acetylation and phosphorylation
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沪深300指数的市场风险预测——基于GARCH模型
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作者 吴婷 《生产力研究》 2024年第6期128-132,共5页
随着金融全球化和自由化程度不断加深,金融市场在得以发展的同时也面临着日益剧烈的市场风险。文章基于2010年1月4日至2024年3月20日沪深300指数日收盘历史数据,运用GARCH模型分别在90%、95%和99%的置信水平下预测沪深300指数市场风险... 随着金融全球化和自由化程度不断加深,金融市场在得以发展的同时也面临着日益剧烈的市场风险。文章基于2010年1月4日至2024年3月20日沪深300指数日收盘历史数据,运用GARCH模型分别在90%、95%和99%的置信水平下预测沪深300指数市场风险。研究显示:(1)GARCH(1,1)正态分布模型在90%、95%、99%置信水平下的失败天数和LR值均未通过检验;(2)GARCH(1,1)-t分布模型在90%置信水平下的失败天数和LR检验值均通过了检验,在95%置信水平下的LR值通过检验,在99%的置信水平下失败天数为0,低估了沪深300指数收益率损失的风险;(3)综合来看,GARCH(1,1)-t分布模型能够更有效地预测沪深股市的市场风险。 展开更多
关键词 GaRCH模型 沪深300指数 市场风险 VaR
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缩短AOD炉冶炼300系不锈钢周期的探讨
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作者 孙如意 卢征统 +2 位作者 姬建民 肖壮 陶冶 《铁合金》 CAS 2024年第1期36-38,共3页
对影响AOD炉冶炼300系不锈钢周期的因素进行了探讨,并针对各影响因素提出了相应的缩短冶炼周期的措施。缩短AOD炉冶炼周期是降本增效的途径之一,影响AOD炉冶炼300系不锈钢周期的主要因素包括热值不足,加入冷料过多、生产协调性欠缺,设... 对影响AOD炉冶炼300系不锈钢周期的因素进行了探讨,并针对各影响因素提出了相应的缩短冶炼周期的措施。缩短AOD炉冶炼周期是降本增效的途径之一,影响AOD炉冶炼300系不锈钢周期的主要因素包括热值不足,加入冷料过多、生产协调性欠缺,设备方面的除尘系统、余热锅炉、下料系统。提出了增加母液供应、原料采购选择、高镍铁水生产要求三个提高入炉原料热值的措施,提升配气人员技术水平、操作制度、现场管理三个生产协调问题解决办法以及除尘系统、余热锅炉系统、下料管改造等三个设备改造方法。期望通过提出的九项解决措施缩短AOD炉冶炼周期,助力钢厂降本增效。 展开更多
关键词 aOD 300 系不锈钢 冶炼周期 降本增效
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贵阳机场APOS300型自动气象站数据异常的分析与研究
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作者 郑迎宾 《传感器技术与应用》 2024年第5期725-733,共9页
文章以贵阳机场APOS300型自动气象站某日数据出现异常情况为例,从现象描述、排查处理过程等方面进行了详细的论述,并根据本场自动气象观测系统的工作机制,详细地分析了异常情况产生的原因。最后,对现有自动气象观测系统外场设备接入的... 文章以贵阳机场APOS300型自动气象站某日数据出现异常情况为例,从现象描述、排查处理过程等方面进行了详细的论述,并根据本场自动气象观测系统的工作机制,详细地分析了异常情况产生的原因。最后,对现有自动气象观测系统外场设备接入的通信模式、防雷、传输质量提升提出了改进的思路和方法。This article takes the APOS300 automatic weather station at Guiyang Airport as an example of an abnormal data situation on a certain day and provides a detailed discussion on the phenomenon description, troubleshooting process, and other aspects. Based on the working mechanism of the automatic weather observation system in this field, the reasons for the abnormal situation are analyzed in detail. Finally, improvement ideas and methods for the communication mode, lightning protection and transmission quality improvement of the access to the existing field equipment of the automatic meteorological observation system are proposed. 展开更多
关键词 自动气象站aPOS300 数据异常 RS-485通信 防雷 上下拉电阻
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APM300型轨道车辆车体碰撞时能量变化研究
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作者 邵志威 钱名鑫 《智慧轨道交通》 2024年第5期20-26,51,共8页
为探究APM300型轨道车辆车体碰撞时能量变化的规律,文章建立碰撞理论模型,利用ANSYS软件,根据EN 15227:2020标准,同时参考国内外相关机车车辆耐碰撞设计规范及准则进行计算。分析AW0和AW2载荷下6辆车编组APM300型轨道车辆在5 km/h、8 k... 为探究APM300型轨道车辆车体碰撞时能量变化的规律,文章建立碰撞理论模型,利用ANSYS软件,根据EN 15227:2020标准,同时参考国内外相关机车车辆耐碰撞设计规范及准则进行计算。分析AW0和AW2载荷下6辆车编组APM300型轨道车辆在5 km/h、8 km/h、12 km/h、13 km/h、15 km/h碰撞速度下的能量分布。研究发现,在初始动能较低时,碰撞产生的能量主要被车钩吸收,随着初始动能的提高,车辆速度约在12 km/h以上时,头车车钩缓冲装置和中间车车钩缓冲装置吸能逐渐平稳,随着速度越高吸能占比逐渐降低,车体吸能所占的比例越来越高。车辆速度在15 km/h时,碰撞的能量变化仍满足EN 15227:2020标准的要求,但随着速度和载荷的增加,剩余动能所占比例越来越大,剩余动能过大而引起猛烈的冲击,导致乘客室内加速度过大,故APM300型轨道车辆极限碰撞速度建议设置为15 km/h。找到车体吸能与速度和载荷的变化规律,可以为车体结构刚度的设计以及车钩吸能缓冲器的选型提供理论依据,为车体结构工程师提供更多的理论数据。 展开更多
关键词 aPM300型轨道车辆 碰撞 能量变化 车体吸能 极限碰撞速度 车体研发
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Tata携手力积电,打造印度首座300mm晶圆厂
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《中国集成电路》 2024年第4期64-64,共1页
2月29日,力积电宣布将协助Tata Electronics公司于古吉拉特邦(Gujarat)多雷拉(Dholera)兴建全印度第一座300mm晶圆厂,预计在今年内动工,未来可望在当地创造超过2万个工作机会。据了解,Tata Electronics为印度最大企业Tata Sons集团旗下... 2月29日,力积电宣布将协助Tata Electronics公司于古吉拉特邦(Gujarat)多雷拉(Dholera)兴建全印度第一座300mm晶圆厂,预计在今年内动工,未来可望在当地创造超过2万个工作机会。据了解,Tata Electronics为印度最大企业Tata Sons集团旗下的全资子公司,Tata Electronics未来计划在多雷拉300mm晶圆厂生产电源管理、面板驱动芯片,以及微控制器、高速计算逻辑芯片,进军车用、计算与存储、无线通信及人工智能等终端应用市场。 展开更多
关键词 古吉拉特邦 电源管理 人工智能 终端应用 全资子公司 无线通信 300mm晶圆厂 逻辑芯片
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1300MPa级在线热处理钢轨使用性能研究 被引量:25
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作者 张银花 周清跃 +1 位作者 陈朝阳 刘丰收 《中国铁道科学》 EI CAS CSCD 北大核心 2008年第6期23-29,共7页
对铺设在北京、太原、上海和郑州铁路局的半径为300-500m曲线上的60kg·m^-1 PG4在线热处理钢轨的使用性能进行跟踪观测,研究提高重载小半径曲线钢轨的使用寿命。研究结果表明,60kg·m^-1PG4在线热处理钢轨硬度高、耐磨性能... 对铺设在北京、太原、上海和郑州铁路局的半径为300-500m曲线上的60kg·m^-1 PG4在线热处理钢轨的使用性能进行跟踪观测,研究提高重载小半径曲线钢轨的使用寿命。研究结果表明,60kg·m^-1PG4在线热处理钢轨硬度高、耐磨性能好;在使用初期,钢轨磨耗少,钢轨表面容易出现剥离掉块,此时如果采用液体润滑,会加剧钢轨表面的剥离掉块;钢轨的磨耗主要出现在曲线的圆缓或缓圆部位,当钢轨磨耗到一定程度后,侧磨加快,如果采用正确的固体润滑方法,可使钢轨的侧磨得到有效地控制,且钢轨不会出现严重的剥离掉块;PG4在线热处理钢轨的综合使用性能良好,耐磨性能比U75V热处理钢轨提高1倍以上,适合在钢轨磨耗严重的重载铁路小半径曲线上使用;对钢轨实施预防性打磨、设置适当的欠超高、采用1:20的轨底坡等改善轮轨匹配关系降低接触应力的措施,均对提高重载铁路曲线区段上钢轨的使用寿命具有重要的作用。 展开更多
关键词 1 300 MPa 在线热处理钢轨 小半径曲线 钢轨磨耗 跟踪观测
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首发抑郁症患者新异Oddball模式下P300波形特征研究 被引量:7
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作者 吕静 苗丹民 +1 位作者 贡京京 王家同 《中国临床心理学杂志》 CSSCI CSCD 2008年第3期230-233,共4页
目的:通过分析首发抑郁症患者在新异Oddball模式下诱发出的P300波形特征,探讨抑郁症患者的认知过程。方法:选取未治疗的青年抑郁症患者12名和正常对照16名,利用新异Oddball模式诱发并记录听觉事件相关电位P300和新异P300。结果:抑郁症... 目的:通过分析首发抑郁症患者在新异Oddball模式下诱发出的P300波形特征,探讨抑郁症患者的认知过程。方法:选取未治疗的青年抑郁症患者12名和正常对照16名,利用新异Oddball模式诱发并记录听觉事件相关电位P300和新异P300。结果:抑郁症组对靶刺激的反应时间(755±244ms)较正常组明显延长(386±114ms);与正常对照组相比,抑郁症组的顶区P3b(P<0.01)与额区P3a(P<0.05)波幅明显降低,额区N2波幅也显著降低(P<0.01);且患者的P3b潜伏期较正常组延迟(P<0.05)。结论:抑郁症患者额叶执行功能受损,集中注意及非随意注意能力下降,事件相关电位P300可为其临床诊断和生理机制提供依据。 展开更多
关键词 事件相关电位 抑郁症 P300 新异P300
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