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Diagnosis and management of benign recurrent intrahepatic cholestasis and psychosocial stressors in an adolescent:A case report
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作者 Ya-Xin Xu Xiao-Xuan Niu +2 位作者 Bei-Li Xu Yuan Ji Qun-Yan Yao 《World Journal of Clinical Cases》 SCIE 2024年第20期4427-4433,共7页
BACKGROUND Benign recurrent intrahepatic cholestasis(BRIC)is a rare autosomal recessive disorder,characterized by episodes of intense pruritus,elevated serum levels of alkaline phosphatase and bilirubin,and near-norma... BACKGROUND Benign recurrent intrahepatic cholestasis(BRIC)is a rare autosomal recessive disorder,characterized by episodes of intense pruritus,elevated serum levels of alkaline phosphatase and bilirubin,and near-normal-glutamyl transferase.These episodes may persist for weeks to months before spontaneously resolving,with patients typically remaining asymptomatic between occurrences.Diagnosis entails the evaluation of clinical symptoms and targeted genetic testing.Although BRIC is recognized as a benign genetic disorder,the triggers,particularly psychosocial factors,remain poorly understood.CASE SUMMARY An 18-year-old Chinese man presented with recurrent jaundice and pruritus after a cold,which was exacerbated by self-medication involving vitamin B and paracetamol.Clinical and laboratory evaluations revealed elevated levels of bilirubin and liver enzymes,in the absence of viral or autoimmune liver disease.Imaging excluded biliary and pancreatic abnormalities,and liver biopsy demonstrated centrilobular cholestasis,culminating in a BRIC diagnosis confirmed by the identification of a novel ATP8B1 gene mutation.Psychological assessment of the patient unveiled stress attributable to academic and familial pressures,regarded as potential triggers for BRIC.Initial relief was observed with ursodeoxycholic acid and cetirizine,followed by an adjustment of the treatment regimen in response to elevated liver enzymes.The patient's condition significantly improved following a stress-related episode,thanks to a comprehensive management approach that included psychosocial support and medical treatment.CONCLUSION Our research highlights genetic and psychosocial influences on BRIC,emphasizing integrated diagnostic and management strategies. 展开更多
关键词 Benign recurrent intrahepatic cholestasis Genetic testing Psychosocial factors ATP8B1 gene mutation cholestasis JAUNDICE PRURITUS Case report
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Extrahepatic cholestasis associated with paracoccidioidomycosis:Challenges in the differential diagnosis of biliopancreatic neoplasia
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作者 Jose Sebastiao dos Santos Vitor de Moura Arrais +9 位作者 William Jose Rosseto Ferreira Ricardo Ribeiro Correa Filho Mariangela Ottoboni Brunaldi Rafael Kemp Ajith Kumar Sankanrakutty Jorge Elias Junior Fernando Bellissimo-Rodrigues Roberto Martinez Edson Zangiacomi Martinez Jose Celso Ardengh 《World Journal of Gastrointestinal Oncology》 SCIE 2024年第6期2531-2540,共10页
BACKGROUND Paracoccidioidomycosis(PCM)may involve the hepatic pedicle and peripan creatic lymph nodes,cause damage to the bile duct and manifest,exceptionally,in combination with extrahepatic cholestasis(EHC),making i... BACKGROUND Paracoccidioidomycosis(PCM)may involve the hepatic pedicle and peripan creatic lymph nodes,cause damage to the bile duct and manifest,exceptionally,in combination with extrahepatic cholestasis(EHC),making investigation and treatment challenging.AIM To investigate the management of patients with visceral PCM admitted with EHC.METHODS All patients diagnosed with PCM treated in a public,tertiary teaching hospital between 1982 and 2020 were retrospectively evaluated.Those also identified with EHC were allocated to two groups according to the treatment approach for the purpose of comparing clinical,laboratory,and imaging findings,resources used for etiological diagnosis,treatment results,and prognosis.Statistical analyses were performed using the linear mixed-effects model(random and fixed effects),which was adjusted using the PROC MIXED procedure of the SAS®9.0 software,and Fisher’s exact test.RESULTS Of 1645 patients diagnosed with PCM,40(2.4%)had EHC.Of these,20(50.0%)lived in the rural area and 29(72.5%)were men,with a mean age of 27.1 years(3-65 years).Jaundice as first symptom and weight loss of at least 10 kg were observed in 16 patients(40.0%),and a mass in the head of the pancreas was observed in 8(20.0%).The etiological diagnosis was made by tissue collection during surgery in 4 cases(10.0%)and by endoscopic methods in 3 cases(7.5%).Twenty-seven patients(67.5%)received drug treatment alone(Group 1),whereas 13(32.5%)underwent endoscopic and/or surgical procedures in combination with drug treatment(Group 2).EHC was significantly reduced in both groups(40.7% in Group 1,with a mean time of 3 months;and 38.4% in Group 2,with a mean time of 7.5 months),with no statistically significant difference between them.EHC recurrence rates,associated mainly with treatment nonadherence,were similar in both groups:37% in Group 1 and 15.4% in Group 2.The mortality rate was 18.5% in Group 1 and 23% in Group 2,with survival estimates of 71.3% and 72.5%,respectively,with no statistically significant difference.CONCLUSION Although PCM-related EHC is rare,it needs to be included in the differential diagnosis of malignancies,as timely treatment can prevent hepatic and extrahepatic sequelae. 展开更多
关键词 cholestasis JAUNDICE Obstructive BLASTOMYCOSIS Paracoccidioides Diagnosis Treatment
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Expression and clinical significance of short-chain fatty acids in patients with intrahepatic cholestasis of pregnancy
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作者 Shuai-Jun Ren Jia-Ting Feng +3 位作者 Ting Xiang Cai-Lian Liao Yu-Ping Zhou Rong-Rong Xuan 《World Journal of Hepatology》 2024年第4期601-611,共11页
BACKGROUND Intrahepatic cholestasis of pregnancy(ICP)is a pregnancy-specific liver condition that typically arises in the middle and late stages of pregnancy.Short-chain fatty acids(SCFAs),prominent metabolites of the... BACKGROUND Intrahepatic cholestasis of pregnancy(ICP)is a pregnancy-specific liver condition that typically arises in the middle and late stages of pregnancy.Short-chain fatty acids(SCFAs),prominent metabolites of the gut microbiota,have significant connections with various pregnancy complications,and some SCFAs hold potential for treating such complications.However,the metabolic profile of SCFAs in patients with ICP remains unclear.AIM To investigate the metabolic profiles and differences in SCFAs present in the maternal and cord blood of patients with ICP and determine the clinical significance of these findings.METHODS Maternal serum and cord blood samples were collected from both patients with ICP(ICP group)and normal pregnant women(NP group).Targeted metabolomics was used to assess the SCFA levels in these samples.RESULTS Significant differences in maternal SCFAs were observed between the ICP and NP groups.Most SCFAs exhibited a consistent declining trend in cord blood samples from the ICP group,mirroring the pattern seen in maternal serum.Correlation analysis revealed a positive correlation between maternal serum SCFAs and cord blood SCFAs[r(Pearson)=0.88,P=7.93e-95].In both maternal serum and cord blood,acetic and caproic acids were identified as key metabolites contributing to the differences in SCFAs between the two groups(variable importance for the projection>1).Receiver operating characteristic analysis demonstrated that multiple SCFAs in maternal blood have excellent diagnostic capabilities for ICP,with caproic acid exhibiting the highest diagnostic efficacy(area under the curve=0.97).CONCLUSION Compared with the NP group,significant alterations were observed in the SCFAs of maternal serum and cord blood in the ICP group,although they displayed distinct patterns of change.Furthermore,the SCFA levels in maternal serum and cord blood were significantly positively correlated.Notably,certain maternal serum SCFAs,specifically caproic and acetic acids,demonstrated excellent diagnostic efficiency for ICP. 展开更多
关键词 Intrahepatic cholestasis of pregnancy Short-chain fatty acids Maternal serum Cord blood Caproic acid
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TC4-DT钛合金切削加工参数研究
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作者 殷志碗 郝宇 +2 位作者 陈伟伦 王东伟 苏楠 《江苏建筑职业技术学院学报》 2024年第1期59-63,93,共6页
针对YG8和TiAlN涂层硬质合金两种刀具,通过单因素车削、低速铣削及正交高速铣削加工试验,探究刀具切削工艺参数对TC4-DT钛合金加工件表面粗糙度、表层硬度的影响规律。实验结果表明:钛合金的表面粗糙度随着切削三要素发生变化,切削速度... 针对YG8和TiAlN涂层硬质合金两种刀具,通过单因素车削、低速铣削及正交高速铣削加工试验,探究刀具切削工艺参数对TC4-DT钛合金加工件表面粗糙度、表层硬度的影响规律。实验结果表明:钛合金的表面粗糙度随着切削三要素发生变化,切削速度越高,粗糙度越低;进给量越大,粗糙度越大;但随切削深度波动变化。使用TiAlN涂层硬质合金立铣刀进行加工得到的平均表面粗糙度小于YG8硬质合金立铣刀,且加工表面硬度变化更小,更适合用于TC4-DT的铣削加工。 展开更多
关键词 TC4-dt钛合金 切削加工 表面粗糙度 正交试验
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Oligo(dT)亲和层析介质的载量比较和机制分析
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作者 谭远志 张鹏程 +3 位作者 孙艳娜 张其磊 姚善泾 林东强 《高校化学工程学报》 EI CAS CSCD 北大核心 2024年第2期243-252,共10页
针对Oligo(d T)亲和层析介质的吸附性能,以poly(A)为模型分子,考察了4种Oligo(d T)亲和层析介质的静态吸附平衡、吸附动力学和动态结合载量(DBC),探讨了载量影响相关机制。结果表明,4种介质的合适吸附条件均为0.6 mol·L-1Na Cl、p ... 针对Oligo(d T)亲和层析介质的吸附性能,以poly(A)为模型分子,考察了4种Oligo(d T)亲和层析介质的静态吸附平衡、吸附动力学和动态结合载量(DBC),探讨了载量影响相关机制。结果表明,4种介质的合适吸附条件均为0.6 mol·L-1Na Cl、p H=6~7;Monomix d T20静态吸附容量最大,且poly(A)能扩散至介质微球深层孔内,而Poros Oligo(d T)25、Praesto Jetted (d T)25和Nano Gel d T20等3种介质中poly(A)均主要为表层吸附、静态吸附容量稍低;对于DBC,Nano Gel d T20和Monomix d T20的10%穿透的DBC较高,而Poros Oligo (d T)25和Praesto Jetted (d T)25相对略低。经分析,影响载量的主要因素包含基质种类、微球孔径、配基密度、间隔臂和配基长度等。对于基质种类,聚苯乙烯基质可能孔道结构较为特别。对于微球孔径,应针对不同大小的m RNA分子定制不同孔径的微球,以平衡传质阻力与可及吸附表面积之间的矛盾,从而增大DBC。 展开更多
关键词 亲和层析 m RNA 寡脱氧胸腺苷酸 载量 生物分离
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Liver stiffness in pregnant women with intrahepatic cholestasis of pregnancy:A case control study
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作者 Juliane Nees Franziska J Ammon +2 位作者 Johannes Mueller Herbert Fluhr Sebastian Mueller 《World Journal of Hepatology》 2023年第7期904-913,共10页
BACKGROUND Intrahepatic cholestasis of pregnancy(ICP)is a rare but severe complication for both the mother and the unborn child.The diagnosis is primarily based on elevated serum levels of bile acids.In a large ICP co... BACKGROUND Intrahepatic cholestasis of pregnancy(ICP)is a rare but severe complication for both the mother and the unborn child.The diagnosis is primarily based on elevated serum levels of bile acids.In a large ICP cohort,we here study in detail liver stiffness(LS)using transient elastography(TE),now widely used to noninvasively screen for liver cirrhosis within minutes.AIM To specifically explore LS in a large cohort of women with ICP compared to a control group with uncomplicated pregnancy.METHODS LS and hepatic steatosis marker controlled attenuation parameter(CAP)were measured in 100 pregnant women with ICP using TE(Fibroscan,Echosens,Paris,France)between 2010 and 2020.In 17 cases,LS could be measured postpartum.450 women before and 38 women after delivery with uncomplicated pregnancy served as control group.Routine laboratory,levels of bile acids and apoptosis marker caspase-cleaved cytokeratin 18 fragment(M30)were also measured.RESULTS Women with ICP had significantly elevated transaminases but normal gammaglutamyl transferase(GGT).Mean LS was significantly increased at 7.3±3.0 kPa compared to the control group at 6.2±2.3 kPa(P<0.0001).Postpartum LS decreased significantly in both groups but was still higher in ICP(5.8±1.7 kPa vs 4.2±0.9 kPa,P<0.0001),respectively.In ICP,LS was highly significantly correlated with levels of bile acids and M30 but not transaminases.No correlation was seen with GGT that even increased significantly after delivery in the ICP group.Bile acids were mostly correlated with the liver apoptosis marker M30,LS and levels of alanine aminotransferase,aspartate aminotransferase,and bilirubin.In multivariate analysis,LS remained the sole parameter that was independently associated with elevated bile acids.CONCLUSION In conclusion,LS is significantly elevated in ICP which is most likely due to toxic bile acid accumulation and hepatocyte apoptosis.In association with conventional laboratory markers,LS provides additional non-invasive information to rapidly identify women at risk for ICP. 展开更多
关键词 Intrahepatic cholestasis of pregnancy Transient elastography Bile acids Liver stiffness High risk pregnancy
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PKGIα通路抑制剂DT-3对胃癌细胞增殖和迁移的影响
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作者 张秀芬 潘理会 李春辉 《河北医学》 CAS 2024年第4期555-560,共6页
目的:探讨PKGIα信号通路特异性抑制剂DT-3对胃癌细胞增殖和迁移的影响。方法:利用生物信息学分析,基于GEO、TCGA、HPA、Kaplan-Meier plotter数据库和GEPIA在线分析网站对PKGI在组织中的表达进行差异分析并探讨PKGI和PKGIα在胃癌患者... 目的:探讨PKGIα信号通路特异性抑制剂DT-3对胃癌细胞增殖和迁移的影响。方法:利用生物信息学分析,基于GEO、TCGA、HPA、Kaplan-Meier plotter数据库和GEPIA在线分析网站对PKGI在组织中的表达进行差异分析并探讨PKGI和PKGIα在胃癌患者中的预后情况。采用CCK-8、克隆形成实验检测DT-3对细胞增殖的影响,划痕愈合实验观察DT-3对细胞迁移的影响;Western blot-ting法验证PKGIα的蛋白表达和相关性分析。结果:胃腺癌组织中PKGI mRNA表达增高,在42种胃癌细胞株里有27种能检测到PKGI mRNA的表达,高表达PKGIαmRNA的胃癌组织更具肿瘤侵袭性;免疫组织化学(IHC)结果展示PKGI蛋白表达情况,12例胃癌组织中观察到6例存在中、高强度的细胞质染色阳性反应;PKGI和CDH1的表达呈负相关(r=-0.74,P<0.05);生存分析显示PKGI和PKGIαmRNA高表达对胃腺癌患者的总生存期(OS)有统计学意义(HR>1,logrank P<0.05)。实验结果表明PKGIα蛋白在人胃癌细胞株AGS中的表达增加;DT-3抑制细胞增殖迁移(P<0.05),使NF-κB磷酸化p65表达降低,且PKGI和NF-κB p-p65的表达呈极强正相关(r=0.957,P<0.05)。结论:通过抑制PKGIα信号通路,可以有效抑制胃癌细胞增殖迁移。 展开更多
关键词 PKGIα通路 dt-3 NF-κB p-p65 生物信息学分析 胃癌细胞AGS
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Effect of polyene phosphatidylcholine/ursodeoxycholic acid/ademetionine on pregnancy outcomes in intrahepatic cholestasis
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作者 Xiao-Rui Dong Qian-Qian Chen +3 位作者 Meng-Ling Xue Ling Wang Qin Wu Teng-Fei Luo 《World Journal of Clinical Cases》 SCIE 2023年第27期6431-6439,共9页
BACKGROUND Intrahepatic cholestasis of pregnancy(ICP)is a liver disorder that occurs in pregnant women and can lead to a range of adverse pregnancy outcomes.The condition is typically marked by pruritus(itching)and el... BACKGROUND Intrahepatic cholestasis of pregnancy(ICP)is a liver disorder that occurs in pregnant women and can lead to a range of adverse pregnancy outcomes.The condition is typically marked by pruritus(itching)and elevated levels of liver enzymes and bile acids.The standard treatment for ICP has generally been ursodeoxycholic acid and ademetionine 1,4-butanedisulfonate,but the efficacy of this approach remains less than optimal.Recently,polyene phosphatidylcholine has emerged as a promising new therapeutic agent for ICP due to its potential hepatoprotective effects.AIM To evaluate the effect of polyene phosphatidylcholine/ursodeoxycholic acid/ademetionine 1,4-butanedisulfonate on bile acid levels,liver enzyme indices,and pregnancy outcomes in patients with ICP.METHODS From June 2020 to June 2021,600 patients with ICP who were diagnosed and treated at our hospital were recruited and assigned at a ratio of 1:1 via randomnumber table method to receive either ursodeoxycholic acid/ademetionine 1,4-butanedisulfonate(control group,n=300)or polyene phosphatidylcholine/ursodeoxycholic acid/ademetionine 1,4-butanedisulfonate(combined group,n=300).Outcome measures included bile acids levels,liver enzyme indices,and pregnancy outcomes.RESULTS Prior to treatment,no significant differences were observed between the two groups(P>0.05).Post-treatment,patients in both groups had significantly lower pruritus scores,but the triple-drug combination group had lower scores than the dual-drug combination group(P<0.05).The bile acid levels decreased significantly in both groups,but the decrease was more significant in the triple-drug group(P<0.05).The triple-drug group also exhibited a greater reduction in the levels of certain liver enzymes and a lower incidence of adverse pregnancy outcomes compared to the dual-drug group(P<0.05).CONCLUSION Polyene phosphatidylcholine/ursodeoxycholic acid/ademetionine 1,4-butanedisulfonate effectively relieves pruritus and reduces bile acid levels and liver enzyme indices in patients with ICP,providing a positive impact on pregnancy outcome and a high safety profile.Further clinical trials are required prior to clinical application. 展开更多
关键词 Ademetionine 1 4-butanedisulfonate Bile acids Intrahepatic cholestasis of pregnancy Liver enzyme indices Polyene phosphatidylcholine Pregnancy outcome Ursodeoxycholic acid
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基于DT‒SVM优化算法的人体姿态特征提取与识别研究 被引量:1
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作者 丁晓慧 周磊 《太原师范学院学报(自然科学版)》 2024年第1期39-44,52,共7页
为确定人体运动行为在空间环境中的表现情况,实现对姿态特征的准确定义,针对基于DT‒SVM优化算法的人体姿态特征提取与识别方法展开研究.利用DT‒SVM优化算法,推荐必要的姿态特征节点,确定人体运动行为所处空间平面.实施对姿态特征的梯度... 为确定人体运动行为在空间环境中的表现情况,实现对姿态特征的准确定义,针对基于DT‒SVM优化算法的人体姿态特征提取与识别方法展开研究.利用DT‒SVM优化算法,推荐必要的姿态特征节点,确定人体运动行为所处空间平面.实施对姿态特征的梯度化处理,根据获取到的轮廓节点,计算夹角向量的具体数值,从而求解姿态特征提取与识别的数学表达式,完成基于DT‒SVM优化算法的人体姿态特征提取与识别方法的设计.实验结果表明,上述方法的应用,可同时在X轴、Y轴、Z轴三个方向上,控制人体运动行为,使其偏向角数值均不超过12°,符合精准定义人体姿态特征的实际应用需求. 展开更多
关键词 dt‒SVM优化算法 人体姿态 特征提取 特征识别 梯度化处理 轮廓节点 夹角向量 运动行为
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TC4-DT合金中片状α相的高精度定量分析方法
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作者 牛冬阳 孙前江 +2 位作者 傅德曹 邬攀易 杨柔萍 《中国有色金属学报》 EI CAS CSCD 北大核心 2024年第8期2684-2696,共13页
针对网篮组织片状α相体积分数难以精确定量分析以及粘连α相难分离表征的问题,结合体视学原理,采用随机森林、遗传算法和改进遗传算法对TC4-DT合金网篮组织片状α相进行表征。首先,预处理采集网篮组织图像;然后,利用样本中片状α相和... 针对网篮组织片状α相体积分数难以精确定量分析以及粘连α相难分离表征的问题,结合体视学原理,采用随机森林、遗传算法和改进遗传算法对TC4-DT合金网篮组织片状α相进行表征。首先,预处理采集网篮组织图像;然后,利用样本中片状α相和β相特征对随机森林模型进行训练。考虑到传统遗传算法图像分割易陷入局部最优解以及收敛速度过快的问题,本文采用精英选择和轮盘赌结合的方法初始化种群,设计了两段式交叉概率和抛物线型变异概率优化遗传算法。最后,利用Java程序验证随机森林模型并自动定量分析片状α相的体积分数,结合实例定量分析片状α相的特征参数。结果表明:采用改进遗传算法运行时时间缩短60%,且图像处理效果也得到提升;随机森林模型不仅在训练样本中的分类准确率达到99.89%,而且在测试样本中的准确率也达到99.29%。这说明随机森林模型能精确地分离片状α相与β相且具有较好的泛化能力。 展开更多
关键词 TC4-dt合金 图像分割 随机森林 改进遗传算法 定量分析
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基于DTS的注水井吸水剖面解释方法
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作者 张玺亮 李昂 +3 位作者 吴杰 王利军 左凯 张志虎 《测井技术》 CAS 2024年第4期537-547,共11页
针对注水井分层注水量诊断技术难题,提出基于分布式光纤温度传感(Distributed Temperature Sensing,DTS)的注水井吸水剖面解释方法。建立考虑微量热效应的注水井温度剖面预测模型,模拟分析注水量、注水时间、储层导热系数等7个因素对温... 针对注水井分层注水量诊断技术难题,提出基于分布式光纤温度传感(Distributed Temperature Sensing,DTS)的注水井吸水剖面解释方法。建立考虑微量热效应的注水井温度剖面预测模型,模拟分析注水量、注水时间、储层导热系数等7个因素对温度剖面的影响规律。通过正交试验模拟分析,确定不同因素对注水井温度剖面的影响程度从强到弱分别为注入水温度、注水时间、注水量、井筒半径、储层导热系数、井筒倾斜角度、注水层渗透率,明确影响注水井温度剖面的主控因素为注入水温度、注水时间和注入量。采用模拟退火(Simulated Annealing,SA)算法建立注水井DTS数据反演模型,对一口注水井现场实测DTS数据进行反演,获得较为准确的吸水剖面,单层最大吸水量误差百分比14.25%,平均误差11.09%,验证该反演方法的可靠性。通过DTS数据反演可以实现注水井吸水剖面定量解释,为注水效果评价提供直接依据。 展开更多
关键词 吸水剖面 dtS 反演模型 注水井 SA算法 温度剖面敏感性
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基于dv/dt参数提取的变流器IGBT驱动自调节技术
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作者 李文鹏 周宇豪 +3 位作者 史志富 董鑫媛 张存凯 张若冰 《铁道机车车辆》 北大核心 2024年第3期97-104,共8页
绝缘栅双极晶体管(IGBT)作为轨道交通变流器关键部件,对其驱动的调节可以显著改善dv/dt、开关损耗等影响变流器运行的重要参数。为此提出了一种基于dv/dt参数提取的变流器IGBT驱动自调节技术。首先基于IGBT驱动等效电路建立数学模型,分... 绝缘栅双极晶体管(IGBT)作为轨道交通变流器关键部件,对其驱动的调节可以显著改善dv/dt、开关损耗等影响变流器运行的重要参数。为此提出了一种基于dv/dt参数提取的变流器IGBT驱动自调节技术。首先基于IGBT驱动等效电路建立数学模型,分析了dv/dt、门极电阻、开关损耗三者之间的数学关系。其次以dv/dt参数的限制为主要优化目标,开关损耗的平衡为约束条件,提出一种基于Bang-Bang控制的自调节控制策略从而实现门极电阻主动切换,并在双脉冲测试中整定控制策略重要参数。最后通过有无自调节技术对比试验测试,验证了本技术的有效性。 展开更多
关键词 绝缘栅双极晶体管(IGBT) dv/dt 驱动自调节 BANG-BANG控制
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输水隧洞液-气界面DTS监测方法
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作者 罗焰 任伟 《科技和产业》 2024年第19期270-277,共8页
输水隧洞的运营状态与其水情息息相关,确定隧洞内液-气界面高度是确保隧洞正常运行的重要前提。基于分布式温度传感(DTS)技术时空连续性、监测便捷性、高空分辨率等特点,提出一种基于DTS技术的输水隧洞液-气界面分布式监测方法及液面高... 输水隧洞的运营状态与其水情息息相关,确定隧洞内液-气界面高度是确保隧洞正常运行的重要前提。基于分布式温度传感(DTS)技术时空连续性、监测便捷性、高空分辨率等特点,提出一种基于DTS技术的输水隧洞液-气界面分布式监测方法及液面高度经验公式,并通过室内模型验证该方法的适用性,分析液面高度、光缆布设角度、加热功率、光缆类型对感测性能的影响。结果表明:DTS液-气界面分布式监测方法配合铜网内加热传感光缆效果最佳,当布设角度为45°、加热时间为2 min,且界面高度处于28 cm及以上时,可以准确反映隧洞内液-气界面高度。 展开更多
关键词 输水隧洞 分布式温度传感(dtS) 液-气界面 温度 分布式监测
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玉米新品种“登海 DT996”选育及栽培技术
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作者 杜德山 孔春英 凌娟 《农业知识》 2024年第5期41-42,共2页
玉米新品种“登海DT996”是枣庄市金苗农作物研究所在2015年以Z1302为母本、Z2159为父本杂交选育而成,夏播生育期为107天。该品种具有抗病抗倒、耐密耐涝、高产优质等特点,适宜山东省夏玉米区域种植利用。
关键词 玉米新品种 选育 登海dt996 栽培技术
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基于卡尔曼滤波的电机直驱系统DT自动化控制
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作者 袁苏楠 《防爆电机》 2024年第5期7-9,21,共4页
为了提高电机直驱系统控制精度,对直驱的双模进行状态和参数的同步,并根据性能指数的限制对扩展态卡尔曼滤波器(SAKF)进行参数的调节,以达到最优的动态特性。研究结果表明:负荷扰动下能够精确地探测到载荷惯性变化,证明了卡尔曼滤波算... 为了提高电机直驱系统控制精度,对直驱的双模进行状态和参数的同步,并根据性能指数的限制对扩展态卡尔曼滤波器(SAKF)进行参数的调节,以达到最优的动态特性。研究结果表明:负荷扰动下能够精确地探测到载荷惯性变化,证明了卡尔曼滤波算法是行之有效的。速度正弦指令跟随精度分析,SAKF在惯性扰动下跟踪准确率比其它控制器要高。SAKF控制器可以有效地保证惯性参数的可变特性,改善系统稳健性和抗干扰能力。速度阶跃指令响应特性分析,负载下SAKF有效地抑制惯性扰动对DTPI的干扰,并保持了系统的设计特性。 展开更多
关键词 电机 直驱系统 dt自动化控制 参数同步方法
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基于DTS的岩溶洼地渗漏室内试验研究
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作者 郭法旺 彭浩 +1 位作者 毛鹏 朱宝强 《陕西水利》 2024年第1期129-132,共4页
岩溶洼地是修建水库的理想场所,但岩溶洼地多位于岩溶强发育区,存在岩溶渗漏难题。在各种渗漏监测方法中,分布式光纤温度传感技术(DTS)有着显著优势。通过分析两类光缆在相同渗漏条件下的温度表现规律、不同介质和加热功率下可加热型光... 岩溶洼地是修建水库的理想场所,但岩溶洼地多位于岩溶强发育区,存在岩溶渗漏难题。在各种渗漏监测方法中,分布式光纤温度传感技术(DTS)有着显著优势。通过分析两类光缆在相同渗漏条件下的温度表现规律、不同介质和加热功率下可加热型光缆的温度特征值、可加热型光缆的渗漏感知范围,验证将加热光缆沿PVC管螺旋缠绕工艺提高渗漏感知能力的效果。研究成果可为DTS在岩溶洼地渗漏监测的应用提供参考。 展开更多
关键词 分布式温度传感(dtS) 岩溶洼地库盆渗漏 模型试验 温度分布 感知能力
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玉米新品种登海DT1819的选育及栽培技术
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作者 李世伟 何涛 +6 位作者 邵鹏 葛松松 夏珍珍 胡艳萍 朱薇 朱文婷 王庆军 《农业科技通讯》 2024年第6期159-161,共3页
登海DT1819是枣庄登海德泰种业有限公司与枣庄市农业农机技术推广中心联合于2015年冬在海南育种基地以自选系Z1302为母本、Z1145为父本杂交选育的玉米新品种。2020-2023年3年平均产量690.5 kg/亩,2020年平均产量755.8 kg/亩。2023年通... 登海DT1819是枣庄登海德泰种业有限公司与枣庄市农业农机技术推广中心联合于2015年冬在海南育种基地以自选系Z1302为母本、Z1145为父本杂交选育的玉米新品种。2020-2023年3年平均产量690.5 kg/亩,2020年平均产量755.8 kg/亩。2023年通过山东省审定。本文作者介绍了该品种的亲本来源、选育经过、特征特性、产量表现及栽培关键技术等,为登海DT1819的推广提供技术参考。 展开更多
关键词 玉米 登海dt1819 选育 栽培技术
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EMS高级应用软件和DTS培训系统在电网运行与调度员培训中的应用
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作者 李祖强 吕长钦 卢非凡 《新潮电子》 2024年第3期28-30,共3页
本文主要介绍EMS高级应用软件和DTS培训系统在电网运行与调度员培训中的应用策略。EMS高级应用软件在电网运行中发挥重要作用,具有监测、控制、优化和安全管理等功能。DTS培训系统则满足调度员培训的需求,通过模拟和实践训练提升其应急... 本文主要介绍EMS高级应用软件和DTS培训系统在电网运行与调度员培训中的应用策略。EMS高级应用软件在电网运行中发挥重要作用,具有监测、控制、优化和安全管理等功能。DTS培训系统则满足调度员培训的需求,通过模拟和实践训练提升其应急处理和团队协作能力。在电网运行与调度员培训的应用策略中,安全管理、运行优化、紧急事件处理和团队协作是关键方面。 展开更多
关键词 EMS高级软件 dtS培训系统 电网运行 调度员
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微电网孤岛运行工况下DT模型自适应迁移方法
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作者 周亮 《电气传动》 2024年第9期50-55,共6页
微电网在孤岛运行工况变化情况下,会造成数字孪生(DT)模型迁移时无法准确匹配源域模型,从而导致迁移效率偏低等问题。为此,研究提出微电网孤岛运行工况变化场景下的数字孪生模型自适应迁移方法。通过分析微电网在孤岛运行工况下的运行特... 微电网在孤岛运行工况变化情况下,会造成数字孪生(DT)模型迁移时无法准确匹配源域模型,从而导致迁移效率偏低等问题。为此,研究提出微电网孤岛运行工况变化场景下的数字孪生模型自适应迁移方法。通过分析微电网在孤岛运行工况下的运行特点,建立数字孪生模型,利用微电网孤岛运行工况的时变性,匹配计算源域模型,并通过缩小不同微电网孤岛运行工况下的源域数据分布差异,实现数字孪生模型的自适应迁移。实验结果表明,电流负载、实际电流等部分特征数据迁移效果较好,且具有较高迁移效率,验证了所提迁移方法可以适应不同微电网孤岛运行工况,具有较好的实用性。 展开更多
关键词 微电网 孤岛运行 工况场景 变化状态 数字孪生模型 自适应迁移
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基于DT/AR技术的智能工厂信息系统设计
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作者 毕云星 《中国新通信》 2024年第3期31-33,共3页
现代智能工程中,信息系统具备一定复杂性和多样性。随着云计算以及物联网等技术的发展,我国提出智能制造2025规划,促进我国生产制造行业的智能化发展。在DT/AR技术的应用下,可以实现生产过程中的精确抓取、数据采集等,有效促进全生命周... 现代智能工程中,信息系统具备一定复杂性和多样性。随着云计算以及物联网等技术的发展,我国提出智能制造2025规划,促进我国生产制造行业的智能化发展。在DT/AR技术的应用下,可以实现生产过程中的精确抓取、数据采集等,有效促进全生命周期的智能生产,进而提升产品研发质量以及生产效率。 展开更多
关键词 dt/AR技术 智能工厂 信息系统设计
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