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Prevention of Gastrointestinal Pathologies: Comparative Study of the Microbial Flora of the Sanitary Surfaces of the Toilets of Students and Staff of the Félix Houphouët-Boigny University
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作者 N’gbesso Jean-Paul N’gbesso Beudje Félicité +3 位作者 Okoubo Née A. Nicaise N’guessan Mambey Serge Juili Landry A. Arra Allou Aime Constantin Ahoua 《Open Journal of Medical Microbiology》 2020年第3期129-138,共10页
<div style="text-align:justify;"> <span style="line-height:1.5;"><span style="font-family:Verdana;"><span style="font-family:Verdana;">Pathologies transm... <div style="text-align:justify;"> <span style="line-height:1.5;"><span style="font-family:Verdana;"><span style="font-family:Verdana;">Pathologies transmissible by hand such as gastrointestinal pathologies constitute a real public health problem, especially in sub-Saharan Africa where hygienic conditions are precarious. This study took place at Félix Houphou</span><span style="white-space:nowrap;font-family:Verdana;">&#235;</span><span style="font-family:Verdana;"></span></span><span style="font-family:Verdana;">t-Boigny</span></span><span "="" style="line-height:1.5;"><span style="font-family:Verdana;"> University from April to August 2018. The samples were taken from toilet surfaces such as doorknobs, tap heads, flush push buttons and seats WC. A total of three hundred and sixty-eight (368) samples were obtained, including 170 from the staff toilets and 198 from the student toilets. The results revealed the presence of total coliforms, </span><i><span style="font-family:Verdana;">Escherichia</span></i><span style="font-family:Verdana;"> spp and </span><i><span style="font-family:Verdana;">Salmonella</span></i><span style="font-family:Verdana;"><span style="font-family:Verdana;"> spp. The surfaces of student toilets were the most contaminated surfaces. The presence of entero-bacteria on the contact surfaces of the toilets of the Félix Houphou</span><span style="white-space:nowrap;font-family:Verdana;">&#235;</span><span style="font-family:Verdana;"></span></span><span style="font-family:Verdana;">t-Boigny university represents a health risk for the university population.</span></span> </div> 展开更多
关键词 Communicable Diseases Hand HYGIENE ENTEROBACTERIACEAE TOILET UNIVERSITY
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基于实测载荷谱下的某电驱动桥桥壳结构强度及寿命分析 被引量:1
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作者 姜良兴 倪大成 +2 位作者 姚超 黄庆 卿鑫慧 《机械强度》 北大核心 2025年第2期10-18,共9页
准确地预估产品的疲劳寿命对于电动汽车关键零部件的结构强度设计以及可靠性设计具有重要作用。以实测强化路道路的载荷谱为出发点,提出了实测载荷谱数据处理与分析的方法,基于Miner准则,得出了车辆在空载、半载以及满载下的载荷数据,... 准确地预估产品的疲劳寿命对于电动汽车关键零部件的结构强度设计以及可靠性设计具有重要作用。以实测强化路道路的载荷谱为出发点,提出了实测载荷谱数据处理与分析的方法,基于Miner准则,得出了车辆在空载、半载以及满载下的载荷数据,通过时域频域处理、损伤等效处理等,得到了可供振动仿真分析以及室内台架试验的关键数据;设计开发了一款平行轴式电驱动桥,针对桥壳等关键部件开展了静力学分析和模态分析,得出了桥壳不会因为路面激励而产生扭转和弯曲现象的结论;基于nCode DesignLife仿真分析软件得出了桥壳疲劳寿命与损伤值分布,通过桥壳耐久试验验证了仿真分析的准确性;基于实测的强化路道路载荷谱,在整车振动试验台上开展了15000 km的强化路室内整车振动试验。试验表明,该电驱动桥产品整体寿命及可靠性满足设计要求,同时验证了分析方法的可靠性。 展开更多
关键词 商用车 电驱动桥 道路载荷谱 疲劳寿命 疲劳分析
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综放工作面末采深孔预注浆加固技术研究
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作者 胡黎明 王春 《煤炭与化工》 2025年第4期36-40,共5页
针对综放工作面末采期间围岩破碎、撤架通道维护困难、高分子化学浆存在安全隐患等问题,设计了末采区域无机材料深孔预注浆加固方案,在顺槽内施工130 m深孔,选择速凝早强和超细高强两种无机注浆材料,采用“0~30~130 m”分段注浆工艺,分... 针对综放工作面末采期间围岩破碎、撤架通道维护困难、高分子化学浆存在安全隐患等问题,设计了末采区域无机材料深孔预注浆加固方案,在顺槽内施工130 m深孔,选择速凝早强和超细高强两种无机注浆材料,采用“0~30~130 m”分段注浆工艺,分别进行端头加固和全长加固。工业性试验结果表明:分段注浆工艺和两种材料保证了有效注浆量,单孔最大注浆量12.6 t,注浆终止压力14 MPa,漏浆极少,工作面进入预注浆加固区域后,片帮、冒顶架次占比为3.8%,远小于未注浆条件下的56%,撤架通道维护良好,工作面安全撤架,无机材料预注浆成本仅为高分子化学浆的38.7%。 展开更多
关键词 末采 撤架通道 分段注浆 无机注浆材料 无机材料预注浆
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考虑强地下水渗流影响的地热开采综合评估
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作者 金涛 杨乐 +3 位作者 温凯 郭攀 杨金才 刘冠男 《能源与环保》 2025年第2期165-174,共10页
在常规的U型管地热开采工程中,采热管跨越地下水渗流地层,其采热效率会受到不同程度的影响。宁夏平原青铜峡库区地热储层地下水充沛,因施工、采热、基建等因素导致地下水渗流现象普遍且复杂,地热储层孔隙率有着复杂的时空非线性演化特... 在常规的U型管地热开采工程中,采热管跨越地下水渗流地层,其采热效率会受到不同程度的影响。宁夏平原青铜峡库区地热储层地下水充沛,因施工、采热、基建等因素导致地下水渗流现象普遍且复杂,地热储层孔隙率有着复杂的时空非线性演化特性。为此,提出了地应力、热传导效应及地下水压力耦合效应下的U型管地热开采模型,并采用有限元方法求解强地下水渗流特性下地热开采效率、地热储层温度及地下水压力的时空演化规律。结果表明,数值模型计算结果与实地地热开采数据吻合较好;不同地下水渗流方向对地热开采的影响显著,由下至上的地下水渗流方向对地热开采最有利;不同地热储层孔隙率对地热开采也有着较为明显的影响。对于地下水由地下向地表渗流的工况来说,更大的地热储层孔隙率有着较好的采热效率;而对于其他地下水渗流方向,更小的地热储层孔隙率更有益于地热开采。研究成果将为宁夏平原强地下水渗流背景下的地热开采提供重要的理论参考依据。 展开更多
关键词 地热储层 地下水渗流 孔隙率 多场耦合 数值模拟
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老龄化背景下防跌倒可穿戴产品的开发现状与前景
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作者 黄鑫鑫 杨淋晖 赵林 《服装学报》 北大核心 2025年第5期424-430,共7页
对2013—2023年跌倒监测技术的演变及防跌倒可穿戴产品的产业化进展进行了回顾与分析。通过梳理国内外相关文献,运用Citespace可视化软件,揭示跌倒预防领域的研究热点和发展趋势。在此基础上,总结跌倒监测技术的发展历程,并分析当前市... 对2013—2023年跌倒监测技术的演变及防跌倒可穿戴产品的产业化进展进行了回顾与分析。通过梳理国内外相关文献,运用Citespace可视化软件,揭示跌倒预防领域的研究热点和发展趋势。在此基础上,总结跌倒监测技术的发展历程,并分析当前市场上典型的防跌倒产品,提出老年人防跌倒可穿戴产品未来可围绕人工智能的个性化风险预测与管理、多传感器融合与智能环境协同、柔性材料与微型化技术提升佩戴舒适性、智能化康复训练与远程医疗支持4个方面进行开发,顺应市场和老年群体的需求。 展开更多
关键词 老龄化 Citespace软件 跌倒监测 可穿戴 产品设计
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Convergence of diabetic ketoacidosis, acute pancreatitis, and malaria: A case report
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作者 Koffi Isidore Kouame Paterne Michael N'kan Mobio +7 位作者 Judith Kouesseu Bouh Jean Kouassi Konan Theodore Klinnan Coulibaly Cyrille Wallamitien Toure Lauraine Armande Assoh Diebi Jose Ndjassipli Homawoo Kouakou Bable Essuy Koffi Paul Yapo Yapo 《World Journal of Clinical Cases》 2025年第23期101-105,共5页
BACKGROUND Type 1 diabetes is an autoimmune disease leading to insulin deficiency,and it is mainly diagnosed in young adults.One of the major acute complications of type 1 diabetes is diabetic ketoacidosis(DKA),which ... BACKGROUND Type 1 diabetes is an autoimmune disease leading to insulin deficiency,and it is mainly diagnosed in young adults.One of the major acute complications of type 1 diabetes is diabetic ketoacidosis(DKA),which is a metabolic emergency that can be triggered by stress,infection,or poor blood glucose control.The association of DKA with conditions such as acute pancreatitis and malaria is rare and therefore represents a major diagnostic and therapeutic challenge.CASE SUMMARY A 20-year-old female was admitted to the emergency room for abdominal pelvic pain,fever,asthenia,polyuria,and polydipsia with a progressive deterioration of her state of consciousness.At admission,she was in a mild coma(Glasgow score:9),had a fever of 38.5°C,and had hyperglycemia(6 g/dL).The tests revealed severe DKA,hypertriglyceridemia,hyperamylasemia,and hyperlipasemia as well as malaria parasite density.The computed tomography scan confirmed acute stage E pancreatitis.The diagnosis was that of inaugural ketoacidosis of type 1 diabetes unbalanced by pancreatitis and malaria.Treatment included insulin therapy,rehydration,and antimalarial and analgesic treatment.After 10 days,the outcome was favorable with a normalization of the blood sugar,and an endocrine follow-up was recommend.CONCLUSION Rapid and multidisciplinary management of DKA,pancreatitis,and malaria led to a favorable and stable prognosis. 展开更多
关键词 Type 1 diabetes Diabetic ketoacidosis Acute pancreatitis MALARIA HYPERTRIGLYCERIDEMIA Case report
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Copula Method and Neural Networks for X-Band Polarimetric Radar Rainfall Retrieval in West Africa
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作者 Sahouarizié Adama Ouattara Eric-Pascal Zahiri +2 位作者 Kadjo Augustin Koffi Modeste Kacou Abé Delfin Ochou 《Journal of Environmental & Earth Sciences》 2025年第4期27-54,共28页
In the context of climate change,countries in West Africa are faced with recurrent flooding with catastrophic consequences,that makes it imperative to have access to rainfall information on fine spatial and temporal s... In the context of climate change,countries in West Africa are faced with recurrent flooding with catastrophic consequences,that makes it imperative to have access to rainfall information on fine spatial and temporal scales for better monitoring and prediction of these phenomena,as could be provided by weather radars.Based on an extensive archive of data from the X-band polarimetric radar and rain gauges observations gathered during the intensive AMMA campaigns in 2006–2007 and the Megha-Tropiques satellite measurement validation programme in 2010 in West Africa,we(i)simulated jointly realistic data for polarimetric radar variables and rain intensity using copula,and(ii)assessed rain rate estimation methods based on neural network(NN)inversion techniques and non-linearly calibrated parametric algorithms.The assessment of rainfall rate retrieval by these estimators is carried out using the part of the observations database not employed for calibration steps.The multiparametric algorithms R(ZH,K_(DP))and R(Z_(DR),K_(DP))perform better than R(ZH,Z_(DR))and R(ZH,Z_(DR),K_(DP)),especially since they are calibrated using copulas with upper tail dependencies,with KGE ranging in 0.68–0.75 and 0.79–0.82,respectively versus ranges of 0.40–0.64 and 0.20–0.51,for the two latter estimators.The neural network-based estimators RNN(Z_(DR),K_(DP))and RNN(ZH,K_(DP)),show KGE score characteristics comparable to those obtained from the best parametric relations,specifically optimized for the synthetic copula-based dataset.However,the neural network-based estimators were shown to be more robust when applied to a specific rainfall event.More specifically,neural network-based estimators trained on synthetic data are sensitive to the copulas’ability to capture the dependence between the variables of interest over the entire distribution of joint values.This leads to a near-cancellation of sensitivity to variability in the raindrop size distribution,as shown the coefficients of correlation near 1,especially for RNN(Z_(DR),K_(DP)),and for less extent RNN(Z_(H),K_(DP)). 展开更多
关键词 Quantitative Precipitation Estimation COPULAS Polarimetric Radar Data Multiparametric Algorithms Artificial Neural Network Non-Linear Fitting
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强地下水渗流下岩层裂隙粗糙程度的地热开采耦合预测
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作者 韩冬 温凯 +3 位作者 叶大羽 杨乐 郭攀 杨金才 《能源与节能》 2025年第1期15-21,共7页
在地热开采过程中,若采热管跨越存在地下水渗流的热岩层,将会对管道传热及热能提取产生显著的影响。作为地下水渗流的主要通道,岩石裂隙的特性演化将显著影响水渗流的行为,继而影响采热管内流体的温度及热开采效率。然而,目前已发表的... 在地热开采过程中,若采热管跨越存在地下水渗流的热岩层,将会对管道传热及热能提取产生显著的影响。作为地下水渗流的主要通道,岩石裂隙的特性演化将显著影响水渗流的行为,继而影响采热管内流体的温度及热开采效率。然而,目前已发表的研究很少能综合探究岩石裂隙粗糙程度对地热开采的影响。因此,提出了一种针对跨越渗流岩层的全耦合地热开采模型,能够综合探究干热岩应力、地下水渗流效应、裂隙粗糙程度及管道传热效应,并提出了定量表征裂隙粗糙程度的参数h/a。结果表明:不同h/a对地层温度及管道流体温度影响显著;当h/a由0.15增加至0.30时,渗流地层水压最多减少了16.7%,地层温度最多降低了3.7℃。 展开更多
关键词 地热开采 地下水渗流 裂隙行为 裂隙粗糙度 数值模拟
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Leveraging farm heterogeneity to enhance living incomes:A gender-sensitive typology of cocoa farming systems in Côte d’Ivoire
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作者 Franziska OLLENDORF Claudia CORAL +2 位作者 Constant Yves ADOU YAO Stefan SIEBER Katharina LÖHR 《Regional Sustainability》 2025年第4期41-60,共20页
About 44%of the world’s cocoa is produced in one single country,Côte d’Ivoire.Providing this important raw material,most Ivorian cocoa farmers live in severe poverty,which,despite a multitude of sector interven... About 44%of the world’s cocoa is produced in one single country,Côte d’Ivoire.Providing this important raw material,most Ivorian cocoa farmers live in severe poverty,which,despite a multitude of sector interventions,is still widespread,affecting social and environmental sustainability in cocoa production.In this context,cocoa farmers are still often treated as a homogeneous group of small-scale producers(mainly males),resulting in interventions being conceptualized as one-size-fits-all approaches and failing to deliver support schemes that take farmers’specific conditions appropriately into account.Applying a broader typology approach that combines farm characteristics with farmers’characteristics,this study aims to delineate Ivorian cocoa farmers and their farms into specific types in order to improve advice for targeted sustainability interventions and living income(LI)potentials.Principal component analysis and hierarchical clustering analysis of a household dataset collected in 2022 in five cocoa-growing regions of Côte d’Ivoire were chosen to identify types of male-headed farms.To assure gender sensitive analysis,a female-headed farm type was created artificially.The specific characteristics of the identified types were captured using descriptive analysis.Descriptive statistics and non-parametric tests were then applied to examine the relationships between these farm types and various outcomes.Additionally,a binary logistic model was used to estimate the probability of these links in relation to variables relevant for achieving a LI.Finally,Spearman non-parametric correlation was used to identify eventual differences in the strength of relationships between key variables per farm type.Three different types of male-headed farms are identified:type 1(the most productive and diversified farms with larger size),type 2(middle-sized farms with strong focus on cash crops),and type 3(small-sized farms with a good level of diversification for self-consumption).The artificially created type 4 represents female-headed farms with the smallest size.On average,none of these farm types achieves a LI.However,type 1 shows the smallest LI gap,while type 4 is by far the worst.Our analyses reveal underlying socio-economic factors systematically disadvantaging female-headed cocoa farms,most notably limited access to land and other material assets.The key contribution of this study lies in the empirical identification of the different characteristics of farms in a given farming system,thereby identifying the need for targeted support interventions.Type-specific recommendations are made,showing pathways to provide tailored programs to farmers of different types in order to reduce their LI gaps. 展开更多
关键词 Living income Farm type Cocoa farmers Cash crops
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Distribution and human health risk assessment of cadmium,arsenic,mercury,lead,and iron in settling particles from the transboundary estuary in three rivers of Cote d’Ivoire,West Africa
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作者 Dehoule N’Guessan Fulgence Kouassi Assy Eudes Yapi +2 位作者 N’Guessan Louis Berenger Kouassi Koffi Marcellin Yao Aoua Sougo Coulibaly 《Acta Geochimica》 2025年第5期1040-1058,共19页
Pollution of transboundary rivers can result from anthropogenic activities in their watersheds.In this study,sediment traps were deployed to determine the fluxes,concentrations,and health risks associated with arsenic... Pollution of transboundary rivers can result from anthropogenic activities in their watersheds.In this study,sediment traps were deployed to determine the fluxes,concentrations,and health risks associated with arsenic,cadmium,mercury,lead,and iron in the estuaries of three transboundary rivers(Comoé,Bia,and Tanoé)in West Africa.Thus,the analysis of metal-associated sedimentation particle samples collected in rainy,flood,and dry seasons was required.Sediment traps were used to calculate the metal fluxes associated with sedimentation particles towards the Atlantic Ocean.Finally,the carcinogenic and non-carcinogenic risks of ingestion and dermal contact associated with sedimentation particles were assessed.The results showed that the total concentrations of trace metals in particulate matter were higher than in the UCC(Upper Crust Continental),with the exception of lead.The highest fluxes of lead,mercury,iron and arsenic associated with sedimented particles were observed during flood periods in the estuary of the Comoé,Bia and Tanoérivers.Cadmium fluxes associated with sedimentation particles were highest in the rainy season in the Bia and Comoéestuaries and in the flood season in the Tanoéestuary.Pearson’s correlation analysis and the enrichment factor showed that the trace metals were derived from anthropogenic activities such as mining and farming.In addition,contamination indices showed that sediment particles in the estuaries of the three rivers were severely contaminated with mercury.However,the results of potential human health risks associated with trace metals show that there is no probability of exposure of the community to harmful and carcinogenic effects through ingestion and dermal absorption of sediment particles.It is essential to integrate the information from this study into policy-and decision-making processes for better management of transboundary river water resources in coastal countries,particularly the Côte d’Ivoire. 展开更多
关键词 Trace metals Settling particles Transboundary rivers Carcinogenic and non-carcinogenic risks ESTUARY West Africa
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Development of bubble point pressure and oil formation volume factor models using pressure-volume-temperature data
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作者 Grant Charles Mwakipunda Allou KoffiFranck Kouassi +3 位作者 Mbula Ngoy Nadege Melckzedeck Michael Mgimba Mbega Ramadhani Ngata Long Yu 《Journal of Rock Mechanics and Geotechnical Engineering》 2025年第11期7127-7146,共20页
The Pressure-Volume-Temperature(PVT)properties of crude oil are typically determined through laboratory analysis during the early phases of exploration and fielddevelopment.However,due to extensive data required,time-... The Pressure-Volume-Temperature(PVT)properties of crude oil are typically determined through laboratory analysis during the early phases of exploration and fielddevelopment.However,due to extensive data required,time-consuming nature,and high costs,laboratory methods are often not preferred.Machine learning,with its efficiencyand rapid convergence,has emerged as a promising alternative for PVT properties estimation.This study employs the modified particle swarm optimization-based group method of data handling(PSO-GMDH)to develop predictive models for estimating both the oil formation volume factor(OFVF)and bubble point pressure(P_(b)).Data from the Mpyo oil fieldin Uganda were used to create the models.The input parameters included solution gas-oil ratio(R_(s)),oil American Petroleum Institute gravity(API),specificgravity(SG),and reservoir temperature(T).The results demonstrated that PSO-GMDH outperformed backpropagation neural networks(BPNN)and radial basis function neural networks(RBFNN),achieving higher correlation coefficientsand lower prediction errors during training and testing.For OFVF prediction,PSO-GMDH yielded a correlation coefficient(R)of 0.9979(training)and 0.9876(testing),with corresponding root mean square error(RMSE)values of 0.0021 and 0.0099,and mean absolute error(MAE)values of 0.00055 and 0.00256,respectively.For P_(b)prediction,R was 0.9994(training)and 0.9876(testing),with RMSE values of 6.08 and 8.26,and MAE values of 1.35 and 2.63.The study also revealed that R_(s)significantlyimpacts OFVF and P_(b)predictions compared to other input parameters.The models followed physical laws and remained stable,demonstrating that PSO-GMDH is a robust and efficientmethod for predicting OFVF and P_(b),offering a time and cost-effective alternative. 展开更多
关键词 Oil formation volume factor Bubble point pressure Pressure-volume-temperature(PVT) PROPERTIES Machine learning
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基于多分类器的无分割手写数字字符串识别算法 被引量:3
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作者 任晓奎 丁鑫 +1 位作者 陶志勇 何欣键 《计算机应用研究》 CSCD 北大核心 2020年第7期2222-2226,共5页
手写体数字字符串识别常用于邮件自动分拣、银行票据和财务报表的录入中,针对其分割识别算法复杂度较高、准确率较低的问题,提出一种多分类器下无分割手写数字字符串识别算法。该算法的核心是采用四个分类器实现粘连字符串的无分割识别... 手写体数字字符串识别常用于邮件自动分拣、银行票据和财务报表的录入中,针对其分割识别算法复杂度较高、准确率较低的问题,提出一种多分类器下无分割手写数字字符串识别算法。该算法的核心是采用四个分类器实现粘连字符串的无分割识别;将残差结构应用于Le Net-5网络,以增加网络深度,提高识别准确率,加快收敛速度;使用动态选择策略,以避免长度分类器误分类对识别结果的影响。实验结果表明,在NIST SD19一位数字和Synthetic数据集训练网络下,使用NIST SD19上长度为2、3、4、5、6的字符串验证网络,其识别准确率分别为99.3%、98.5%、98.1%、96.6%和97.2%。 展开更多
关键词 图像处理 手写数字字符串识别 多分类器 无分割 动态选择
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基于改进花朵授粉的K-均值聚类算法 被引量:2
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作者 陶志勇 刘晓芳 +1 位作者 刘影 王和章 《计算机应用研究》 CSCD 北大核心 2019年第11期3253-3257,共5页
针对K-means聚类算法依赖于初始值并易陷入局部最优值的问题,提出了一种基于改进花朵授粉的K-means聚类算法。该算法首先通过混沌映射的序列作为花朵种群的初值位置,保证花朵种群在搜索空间的多样性、确定性;然后在花朵授粉的后期搜索... 针对K-means聚类算法依赖于初始值并易陷入局部最优值的问题,提出了一种基于改进花朵授粉的K-means聚类算法。该算法首先通过混沌映射的序列作为花朵种群的初值位置,保证花朵种群在搜索空间的多样性、确定性;然后在花朵授粉的后期搜索阶段引入禁忌搜索算法以避免陷入局部最优解;最后将改进后的FPA算法用于优化K-means算法的初值。在五个聚类数据集上的实验结果表明,改进后算法的平均聚类准确率相比于花朵授粉聚类算法提高了12.2%,证明了该算法对于低维数据集具有更好的聚类效果。 展开更多
关键词 聚类 花朵授粉 混沌映射 禁忌搜索 K-MEANS
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融合密度峰值的高斯混合模型聚类算法 被引量:11
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作者 陶志勇 刘晓芳 王和章 《计算机应用》 CSCD 北大核心 2018年第12期3433-3437,3443,共6页
针对高斯混合模型(GMM)聚类算法对初始值敏感且容易陷入局部极小值的问题,利用密度峰值(DP)算法全局搜索能力强的优势,对GMM算法的初始聚类中心进行优化,提出了一种融合DP的GMM聚类算法(DPGMMC)。首先,基于DP算法寻找聚类中心,得到混合... 针对高斯混合模型(GMM)聚类算法对初始值敏感且容易陷入局部极小值的问题,利用密度峰值(DP)算法全局搜索能力强的优势,对GMM算法的初始聚类中心进行优化,提出了一种融合DP的GMM聚类算法(DPGMMC)。首先,基于DP算法寻找聚类中心,得到混合模型的初始参数;其次,采用最大期望(EM)算法迭代估计混合模型的参数;最后,根据贝叶斯后验概率准则实现数据点的聚类。在Iris数据集下,DP-GMMC聚类准确率可达到96. 67%,与传统GMM算法相比提高了33. 6个百分点,解决了对初始聚类中心依赖的问题。实验结果表明,DP-GMMC对低维数据集有较好的聚类效果。 展开更多
关键词 聚类 高斯混合模型 最大期望算法 密度峰值
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嵌入常识的混合注意力LSTM用于主题情感分析 被引量:2
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作者 任晓奎 郭娟 陶志勇 《计算机应用与软件》 北大核心 2019年第10期151-155,161,共6页
传统神经网络模型在捕捉上下文信息时,缺乏对于某一主题重要线索的准确分析能力。对此提出嵌入常识知识库的混合注意力长短时记忆网络(LSTM)主题情感分析模型。通过引入全局注意力和位置注意力机制来改进长短时记忆网络LSTM;将常识知识... 传统神经网络模型在捕捉上下文信息时,缺乏对于某一主题重要线索的准确分析能力。对此提出嵌入常识知识库的混合注意力长短时记忆网络(LSTM)主题情感分析模型。通过引入全局注意力和位置注意力机制来改进长短时记忆网络LSTM;将常识知识库嵌入到LSTM的情感分类训练中。该模型在推断特定主题的情感极性时明确地抓住了每个上下文词的重要性,使分类更加准确。实验结果表明,混合注意力模型与常识知识库的引入,提高了主题情感分析的分类效果。 展开更多
关键词 情感分析 常识知识 注意力机制 LSTM
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基于迁移学习的指静脉与指关节纹分数级融合的识别研究 被引量:1
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作者 陶志勇 冯媛 林森 《计算机应用与软件》 北大核心 2019年第12期162-168,183,共8页
针对手指静脉与手指关节纹的数据样本小且识别准确率易受各自固有属性限制以及非注册用户对系统识别准确率影响较大等问题,提出一种基于迁移学习的带拒绝识别阈值的手指静脉与手指关节纹共同决策同一主体的双模态分数级融合识别方法。... 针对手指静脉与手指关节纹的数据样本小且识别准确率易受各自固有属性限制以及非注册用户对系统识别准确率影响较大等问题,提出一种基于迁移学习的带拒绝识别阈值的手指静脉与手指关节纹共同决策同一主体的双模态分数级融合识别方法。对二者数据集进行数据扩充和图像尺寸调整;使用经ImageNet海量数据集训练后的Vgg19、Inceptionv3、Xception以及Resnet分别在二者数据集上进行参数调优;应用调优后的新模型进行分类识别,得到各自的匹配分数,再进行分数级融合,融合后的匹配分数与拒绝识别阈值比较,再进行最终的决策。该方法在公开数据集中识别准确率均可达99%,较各自单模态在各个网络中的识别准确率提高0.33%~15%不等。实验结果表明,采用迁移学习方法对指静脉与指关节纹进行分数级融合能够有效提高系统的识别准确率。 展开更多
关键词 手指静脉识别 手指关节纹识别 迁移学习 分数级融合
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健美操专项学生运动损伤情况调查 被引量:3
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作者 徐健 王洁 《武术研究》 2020年第9期137-139,共3页
竞技健美操运动员受伤部位多是腕、肩及腰部,损伤的主要原因是:技术、训练水平偏低,身体素质差,自我运动意识不强、动作不正确,缺乏自我保护能力;运动前不做准备活动或准备活动不充分,身体状态不佳,以及教学、竞赛工作组织不当。以北京... 竞技健美操运动员受伤部位多是腕、肩及腰部,损伤的主要原因是:技术、训练水平偏低,身体素质差,自我运动意识不强、动作不正确,缺乏自我保护能力;运动前不做准备活动或准备活动不充分,身体状态不佳,以及教学、竞赛工作组织不当。以北京体育大学体育艺术系健美操专项学生为研究对象,采用文献资料法、问卷调查法、数理统计法、逻辑分析法,就健美操专项学生运动损伤情况进行了调查,发现健美操专项学生运动损伤发生的机率随着学期、课程的不同而不同;运动损伤较多的部位是踝关节、膝关节、腕关节、颈部、腰部、大腿等;损伤性质多为拉伤、扭伤、挫伤、擦伤;损伤的原因主要是动作技术掌握不当、着装不当、准备活动不充分、注意力不集中等。从提高学生预防运动损伤的意识、正确着装、加强易伤部位的力量和伸展性练习等方面有针对性地提出建议。 展开更多
关键词 健美操专业 运动损伤 调查
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离子交换法分离纯化还原型谷胱甘肽的研究 被引量:3
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作者 崔秀云 邵千飞 《广州化工》 CAS 2018年第15期84-86,95,共4页
还原型谷胱甘肽是一种重要的生物活性化合物,广泛应用于食品、医药和化妆品等领域,具有重要的实际应用价值和产业前景。通过5种树脂(LX-18,732,SP,HD-8,XDA-1)对谷胱甘肽进行静态吸附研究,筛选出在酸性条件下具有较高吸附量的732阳离子... 还原型谷胱甘肽是一种重要的生物活性化合物,广泛应用于食品、医药和化妆品等领域,具有重要的实际应用价值和产业前景。通过5种树脂(LX-18,732,SP,HD-8,XDA-1)对谷胱甘肽进行静态吸附研究,筛选出在酸性条件下具有较高吸附量的732阳离子树脂。确定732树脂的动态吸附工艺:吸附流速为0.5 m L/min,最佳洗脱液为氯化钠溶液,且最佳洗脱浓度为2%,洗脱流速为0.8 m L/min,在最优条件下谷胱甘肽的回收率可以达到65.08%。 展开更多
关键词 还原型谷胱甘肽 离子交换树脂 分离纯化
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一种面向标识公共递归解析节点的数据安全加固策略 被引量:1
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作者 刘文军 陈晨 狄航 《信息通信技术与政策》 2023年第11期18-24,共7页
为解决工业互联网标识解析体系公共递归解析节点信息透明、缺乏隐私数据保护和身份权限管理等问题,提出了一种面向标识公共递归解析节点的数据安全加固策略。通过设计加密机制及细粒度权限查验机制,实现了标识解析二级节点的编码注册和... 为解决工业互联网标识解析体系公共递归解析节点信息透明、缺乏隐私数据保护和身份权限管理等问题,提出了一种面向标识公共递归解析节点的数据安全加固策略。通过设计加密机制及细粒度权限查验机制,实现了标识解析二级节点的编码注册和解析服务的安全加固,提高了标识解析数据共享的安全性,验证了该方案的有效性。 展开更多
关键词 工业互联网 标识解析 安全加固 二级节点
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二乙二醇二乙醚的合成工艺优化 被引量:1
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作者 崔秀云 邵千飞 +1 位作者 汪德林 田健 《科技视界》 2018年第17期224-226,共3页
以二乙二醇单乙醚、氯乙烷和碱为基本原料,四丁基溴化铵为催化剂,通过Williamson反应合成二乙二醇二乙醚。考察了碱的加入量、催化剂的用量和反应温度等因素对反应转化率的影响,确定了最佳反应条件:以100g二乙二醇单乙醚为基准,n(单乙醚... 以二乙二醇单乙醚、氯乙烷和碱为基本原料,四丁基溴化铵为催化剂,通过Williamson反应合成二乙二醇二乙醚。考察了碱的加入量、催化剂的用量和反应温度等因素对反应转化率的影响,确定了最佳反应条件:以100g二乙二醇单乙醚为基准,n(单乙醚):n(Na OH)=1:1.5,四丁基溴化铵为二乙二醇单乙醚质量的5%,温度为115℃,反应时间为3.0h,在此条件下二乙二醇二乙醚的转化率达到最好且原料利用率最高,该工艺具有毒性小、副产少、反应时间短、反应条件不苛刻、转化率高的优点。 展开更多
关键词 二乙二醇二乙醚 四丁基溴化铵 优化
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