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BAT评分联合CTA点征对幕上自发性脑出血患者早期血肿扩大的预测价值研究 被引量:1
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作者 李娜 姬泽强 +2 位作者 文心瑜 吴蕾 赵性泉 《中国卒中杂志》 2023年第7期780-786,共7页
目的研究BAT评分联合CTA点征对幕上自发性脑出血患者早期血肿扩大的预测价值。方法回顾性分析2021年9月—2022年4月连续于首都医科大学附属北京天坛医院急诊就诊且发病至一站式CT检查时间在6 h内的幕上自发性脑出血患者的资料,根据发病... 目的研究BAT评分联合CTA点征对幕上自发性脑出血患者早期血肿扩大的预测价值。方法回顾性分析2021年9月—2022年4月连续于首都医科大学附属北京天坛医院急诊就诊且发病至一站式CT检查时间在6 h内的幕上自发性脑出血患者的资料,根据发病后24~48 h复查头颅CT与基线CT的血肿体积对比,分为血肿扩大组和非血肿扩大组。比较两组患者的基本临床资料、CTA点征及非增强CT(non-contrast computed tomography sign,NCCT)特点(低密度征、混合征等)影像资料、BAT评分(blend sign,any hypodensity,timing of NCCT score,BAT)。采用单因素分析和多因素logistic回归分析血肿扩大的危险因素,并绘制ROC曲线分析BAT评分、CTA点征及两者结合对自发性脑出血患者早期血肿扩大的预测价值。结果共纳入97例患者,血肿扩大组28例,非血肿扩大组69例。血肿扩大组患者CTA点征,NCCT低密度征、混合征的发生率均高于非血肿扩大组,BAT评分中位数和BAT评分≥3分的患者比例均高于非血肿扩大组,发病至基线影像时间短于非血肿扩大组,基线出血体积和基线随机血糖水平高于非血肿扩大组,上述差异均有统计学意义。多因素logistic回归分析结果显示,CTA点征阳性(OR 31.828,95%CI 5.350~189.337,P<0.01)、BAT评分≥3分(OR 71.976,95%CI 5.391~960.899,P<0.01)、基线出血体积(OR 1.029,95%CI 1.003~1.055,P=0.03)和基线随机血糖(OR 1.355,95%CI 1.070~1.714,P=0.01)可独立预测血肿扩大。ROC曲线分析显示,基线出血体积预测血肿扩大的AUC为0.762,BAT评分≥3分预测血肿扩大的AUC为0.716,CTA点征阳性预测血肿扩大的AUC为0.756,BAT评分≥3分联合CTA点征阳性预测血肿扩大的AUC为0.833。De Long检验提示两者联合预测效力优于单独预测效力(P<0.05)。结论幕上自发性脑出血患者发病6 h内,BAT评分≥3分及CTA点征阳性都可有效预测血肿扩大,两者联合预测的效力更佳。 展开更多
关键词 自发性脑出血 bat评分 点征 计算机断层扫描血管造影 计算机断层扫描 血肿扩大
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Technique for Multi-Pass Turning Optimization Based on Gaussian Quantum-Behaved Bat Algorithm
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作者 Shutong Xie Zongbao He Xingwang Huang 《Computer Modeling in Engineering & Sciences》 SCIE EI 2023年第8期1575-1602,共28页
The multi-pass turning operation is one of the most commonly used machining methods in manufacturing field.The main objective of this operation is to minimize the unit production cost.This paper proposes a Gaussian qu... The multi-pass turning operation is one of the most commonly used machining methods in manufacturing field.The main objective of this operation is to minimize the unit production cost.This paper proposes a Gaussian quantum-behaved bat algorithm(GQBA)to solve the problem of multi-pass turning operation.The proposed algorithm mainly includes the following two improvements.The first improvement is to incorporate the current optimal positions of quantum bats and the global best position into the stochastic attractor to facilitate population diversification.The second improvement is to use a Gaussian distribution instead of the uniform distribution to update the positions of the quantum-behaved bats,thus performing a more accurate search and avoiding premature convergence.The performance of the presented GQBA is demonstrated through numerical benchmark functions and amulti-pass turning operation problem.Thirteen classical benchmark functions are utilized in the comparison experiments,and the experimental results for accuracy and convergence speed demonstrate that,in most cases,the GQBA can provide a better search capability than other algorithms.Furthermore,GQBA is applied to an optimization problem formulti-pass turning,which is designed tominimize the production cost while considering many practical machining constraints in the machining process.The experimental results indicate that the GQBA outperforms other comparison algorithms in terms of cost reduction,which proves the effectiveness of the GQBA. 展开更多
关键词 bat algorithm quantum behavior gaussian distribution numerical optimization multi-pass turning
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Improved Bat Algorithm with Deep Learning-Based Biomedical ECG Signal Classification Model
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作者 Marwa Obayya Nadhem NEMRI +5 位作者 Lubna A.Alharbi Mohamed K.Nour Mrim M.Alnfiai Mohammed Abdullah Al-Hagery Nermin M.Salem Mesfer Al Duhayyim 《Computers, Materials & Continua》 SCIE EI 2023年第2期3151-3166,共16页
With new developments experienced in Internet of Things(IoT),wearable,and sensing technology,the value of healthcare services has enhanced.This evolution has brought significant changes from conventional medicine-base... With new developments experienced in Internet of Things(IoT),wearable,and sensing technology,the value of healthcare services has enhanced.This evolution has brought significant changes from conventional medicine-based healthcare to real-time observation-based healthcare.Biomedical Electrocardiogram(ECG)signals are generally utilized in examination and diagnosis of Cardiovascular Diseases(CVDs)since it is quick and non-invasive in nature.Due to increasing number of patients in recent years,the classifier efficiency gets reduced due to high variances observed in ECG signal patterns obtained from patients.In such scenario computer-assisted automated diagnostic tools are important for classification of ECG signals.The current study devises an Improved Bat Algorithm with Deep Learning Based Biomedical ECGSignal Classification(IBADL-BECGC)approach.To accomplish this,the proposed IBADL-BECGC model initially pre-processes the input signals.Besides,IBADL-BECGC model applies NasNet model to derive the features from test ECG signals.In addition,Improved Bat Algorithm(IBA)is employed to optimally fine-tune the hyperparameters related to NasNet approach.Finally,Extreme Learning Machine(ELM)classification algorithm is executed to perform ECG classification method.The presented IBADL-BECGC model was experimentally validated utilizing benchmark dataset.The comparison study outcomes established the improved performance of IBADL-BECGC model over other existing methodologies since the former achieved a maximum accuracy of 97.49%. 展开更多
关键词 Data science ECG signals improved bat algorithm deep learning biomedical data data classification machine learning
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高血压脑出血患者短期预后的影响因素及BAT评分的预测效果
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作者 陈宏尊 陈颖虎 《国际神经病学神经外科学杂志》 2023年第3期16-20,共5页
目的 分析高血压脑出血患者短期预后的影响因素及非增强CT 5分预测法(BAT)评分的预测效果。方法 2016年1月—2020年12月在中国人民解放军南部战区海军第二医院治疗的618例高血压脑出血患者,将其中术后28 d内死亡的62例患者设为死亡组,其... 目的 分析高血压脑出血患者短期预后的影响因素及非增强CT 5分预测法(BAT)评分的预测效果。方法 2016年1月—2020年12月在中国人民解放军南部战区海军第二医院治疗的618例高血压脑出血患者,将其中术后28 d内死亡的62例患者设为死亡组,其余556例存活的患者设为存活组。分析高血压脑出血患者术后28 d内死亡的影响因素,并采用受试者操作特征(ROC)曲线分析BAT评分对高血压脑出血患者术后28 d内死亡的预测价值。结果 术前24 h格拉斯哥昏迷量表(GCS)评分<6分、BAT评分≥4分、首次CT距发病时间短、合并术后24 h并发症为高血压脑出血患者术后28 d内死亡的影响因素(P<0.05)。ROC曲线分析显示,BAT评分预测高血压脑出血患者术后28 d内死亡的ROC曲线下面积(AUC)为0.892(P<0.01),95%CI为0.789~0.932,最佳截断值为4分,敏感度为88.29%,特异度为81.43%。结论 术前24 h GCS评分、BAT评分、首次CT距发病时间、术后24 h并发症为高血压脑出血患者术后28 d内死亡的影响因素,且BAT评分对患者预后有较佳的预测价值。 展开更多
关键词 高血压脑出血 生存状况 危险因素 非增强CT 5分预测法评分 预测
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Bat 26 Microsatellite Instability in Oral Cavity Cancers in Senegal
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作者 Mame Diarra Samb Fatimata Mbaye +2 位作者 Mouhamadou Makhtar Ndiaye Silly Toure Mbacke Sembene 《Journal of Cancer Therapy》 CAS 2023年第1期25-37,共13页
Oral cavity cancers are part of head and neck cancers. They have become frequent in the world in general and Senegal in particular. This study evaluates microsatellite instability tumors in oral cavity cancers in Sene... Oral cavity cancers are part of head and neck cancers. They have become frequent in the world in general and Senegal in particular. This study evaluates microsatellite instability tumors in oral cavity cancers in Senegal. Forty cancerous tissues, 20 healthy tissues, and 12 blood tissues were included in this study. These tissues were collected from each patient during the biopsy after obtaining consent. DNA extraction, Polymerase Chain Reaction (PCR) and sequencing were carried out to obtain sequences. Mutation surveyor, Bioedit and Dnasp software were used to perform our analyses. High instability was found in 57.5% of patients with cancer. Moreover, 90% of the patients had the same motif on healthy and cancerous tissue. Furthermore, 26.12%, 20.72%, and 11.71% polymorphic sites were found in cancerous, healthy and blood tissue respectively. Thus, a similarity between cancerous and healthy tissues seems to exist. This implies that instability of the Bat 26 microsatellite could occur early in the occurrence of oral cavity cancers. 展开更多
关键词 CANCER Oral Cavity Microsatellite Instability bat 26 Senegal
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The Human Eye Pupil Detection System Using BAT Optimized Deep Learning Architecture
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作者 S.Navaneethan P.Siva Satya Sreedhar +1 位作者 S.Padmakala C.Senthilkumar 《Computer Systems Science & Engineering》 SCIE EI 2023年第7期125-135,共11页
The pupil recognition method is helpful in many real-time systems,including ophthalmology testing devices,wheelchair assistance,and so on.The pupil detection system is a very difficult process in a wide range of datas... The pupil recognition method is helpful in many real-time systems,including ophthalmology testing devices,wheelchair assistance,and so on.The pupil detection system is a very difficult process in a wide range of datasets due to problems caused by varying pupil size,occlusion of eyelids,and eyelashes.Deep Convolutional Neural Networks(DCNN)are being used in pupil recognition systems and have shown promising results in terms of accuracy.To improve accuracy and cope with larger datasets,this research work proposes BOC(BAT Optimized CNN)-IrisNet,which consists of optimizing input weights and hidden layers of DCNN using the evolutionary BAT algorithm to efficiently find the human eye pupil region.The proposed method is based on very deep architecture and many tricks from recently developed popular CNNs.Experiment results show that the BOC-IrisNet proposal can efficiently model iris microstructures and provides a stable discriminating iris representation that is lightweight,easy to implement,and of cutting-edge accuracy.Finally,the region-based black box method for determining pupil center coordinates was introduced.The proposed architecture was tested using various IRIS databases,including the CASIA(Chinese academy of the scientific research institute of automation)Iris V4 dataset,which has 99.5%sensitivity and 99.75%accuracy,and the IIT(Indian Institute of Technology)Delhi dataset,which has 99.35%specificity and MMU(Multimedia University)99.45%accuracy,which is higher than the existing architectures. 展开更多
关键词 bat algorithm IRIS datasets DCNN pupil detection black box method
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Neighborhood Search Based Improved Bat Algorithm for Web Service Composition
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作者 Fadl Dahan 《Computer Systems Science & Engineering》 SCIE EI 2023年第5期1343-1356,共14页
Web services are provided as reusable software components in the services-oriented architecture.More complicated composite services can be combined from these components to satisfy the user requirements represented as... Web services are provided as reusable software components in the services-oriented architecture.More complicated composite services can be combined from these components to satisfy the user requirements represented as a workflow with specified Quality of Service(QoS)limitations.The workflow consists of tasks where many services can be considered for each task.Searching for optimal services combination and optimizing the overall QoS limitations is a Non-deterministic Polynomial(NP)-hard problem.This work focuses on the Web Service Composition(WSC)problem and proposes a new service composition algorithm based on the micro-bats behavior while hunting the prey.The proposed algorithm determines the optimal combination of the web services to satisfy the complex user needs.It also addresses the Bat Algorithm(BA)shortcomings,such as the tradeoff among exploration and exploitation searching mechanisms,local optima,and convergence rate.The proposed enhancement includes a developed cooperative and adaptive population initialization mechanism.An elitist mechanism is utilized to address the BA convergence rate.The tradeoff between exploration and exploitation is handled through a neighborhood search mechanism.Several benchmark datasets are selected to evaluate the proposed bat algorithm’s performance.The simulation results are estimated using the average fitness value,the standard deviation of the fitness value,and an average of the execution time and compared with four bat-inspired algorithms.It is observed from the simulation results that introduced enhancement obtains significant results. 展开更多
关键词 Cloud computing web service composition bat algorithm serviceoriented architecture
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Hybridizing Artificial Bee Colony with Bat Algorithm for Web Service Composition
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作者 Tariq Ahamed Ahanger Fadl Dahan Usman Tariq 《Computer Systems Science & Engineering》 SCIE EI 2023年第8期2429-2445,共17页
In the Internet of Things(IoT),the users have complex needs,and the Web Service Composition(WSC)was introduced to address these needs.The WSC’s main objective is to search for the optimal combination of web services ... In the Internet of Things(IoT),the users have complex needs,and the Web Service Composition(WSC)was introduced to address these needs.The WSC’s main objective is to search for the optimal combination of web services in response to the user needs and the level of Quality of Services(QoS)constraints.The challenge of this problem is the huge number of web services that achieve similar functionality with different levels of QoS constraints.In this paper,we introduce an extension of our previous works on the Artificial Bee Colony(ABC)and Bat Algorithm(BA).A new hybrid algorithm was proposed between the ABC and BA to achieve a better tradeoff between local exploitation and global search.The bat agent is used to improve the solution of exhausted bees after a threshold(limits),and also an Elitist Strategy(ES)is added to BA to increase the convergence rate.The performance and convergence behavior of the proposed hybrid algorithm was tested using extensive comparative experiments with current state-ofthe-art nature-inspired algorithms on 12 benchmark datasets using three evaluation criteria(average fitness values,best fitness values,and execution time)that were measured for 30 different runs.These datasets are created from real-world datasets and artificially to form different scale sizes of WSC datasets.The results show that the proposed algorithm enhances the search performance and convergence rate on finding the near-optimal web services combination compared to competitors.TheWilcoxon signed-rank significant test is usedwhere the proposed algorithm results significantly differ fromother algorithms on 100%of datasets. 展开更多
关键词 Internet of things artificial bee colony bat algorithm elitist strategy web service composition
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Hybrid Deep Learning-Improved BAT Optimization Algorithm for Soil Classification Using Hyperspectral Features
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作者 S.Prasanna Bharathi S.Srinivasan +1 位作者 G.Chamundeeswari B.Ramesh 《Computer Systems Science & Engineering》 SCIE EI 2023年第4期579-594,共16页
Now a days,Remote Sensing(RS)techniques are used for earth observation and for detection of soil types with high accuracy and better reliability.This technique provides perspective view of spatial resolution and aids ... Now a days,Remote Sensing(RS)techniques are used for earth observation and for detection of soil types with high accuracy and better reliability.This technique provides perspective view of spatial resolution and aids in instantaneous measurement of soil’s minerals and its characteristics.There are a few challenges that is present in soil classification using image enhancement such as,locating and plotting soil boundaries,slopes,hazardous areas,drainage condition,land use,vegetation etc.There are some traditional approaches which involves few drawbacks such as,manual involvement which results in inaccuracy due to human interference,time consuming,inconsistent prediction etc.To overcome these draw backs and to improve the predictive analysis of soil characteristics,we propose a Hybrid Deep Learning improved BAT optimization algorithm(HDIB)for soil classification using remote sensing hyperspectral features.In HDIB,we propose a spontaneous BAT optimization algorithm for feature extraction of both spectral-spatial features by choosing pure pixels from the Hyper Spectral(HS)image.Spectral-spatial vector as training illustrations is attained by merging spatial and spectral vector by means of priority stacking methodology.Then,a recurring Deep Learning(DL)Neural Network(NN)is used for classifying the HS images,considering the datasets of Pavia University,Salinas and Tamil Nadu Hill Scene,which in turn improves the reliability of classification.Finally,the performance of the proposed HDIB based soil classifier is compared and analyzed with existing methodologies like Single Layer Perceptron(SLP),Convolutional Neural Networks(CNN)and Deep Metric Learning(DML)and it shows an improved classification accuracy of 99.87%,98.34%and 99.9%for Tamil Nadu Hills dataset,Pavia University and Salinas scene datasets respectively. 展开更多
关键词 HDIB bat optimization algorithm recurrent deep learning neural network convolutional neural network single layer perceptron hyperspectral images deep metric learning
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Tasks Scheduling in Cloud Environment Using PSO-BATS with MLRHE
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作者 Anwar R Shaheen Sundar Santhosh Kumar 《Intelligent Automation & Soft Computing》 SCIE 2023年第3期2963-2978,共16页
Cloud computing plays a significant role in Information Technology(IT)industry to deliver scalable resources as a service.One of the most important factor to increase the performance of the cloud server is maximizing t... Cloud computing plays a significant role in Information Technology(IT)industry to deliver scalable resources as a service.One of the most important factor to increase the performance of the cloud server is maximizing the resource utilization in task scheduling.The main advantage of this scheduling is to max-imize the performance and minimize the time loss.Various researchers examined numerous scheduling methods to achieve Quality of Service(QoS)and to reduce execution time.However,it had disadvantages in terms of low throughput and high response time.Hence,this study aimed to schedule the task efficiently and to eliminate the faults in scheduling the tasks to the Virtual Machines(VMs).For this purpose,the research proposed novel Particle Swarm Optimization-Bandwidth Aware divisible Task(PSO-BATS)scheduling with Multi-Layered Regression Host Employment(MLRHE)to sort out the issues of task scheduling and ease the scheduling operation by load balancing.The proposed efficient sche-duling provides benefits to both cloud users and servers.The performance evalua-tion is undertaken with respect to cost,Performance Improvement Rate(PIR)and makespan which revealed the efficiency of the proposed method.Additionally,comparative analysis is undertaken which confirmed the performance of the intro-duced system than conventional system for scheduling tasks with highflexibility. 展开更多
关键词 Task scheduling virtual machines(VM) particle swarm optimization(PSO) bandwidth aware divisible task scheduling(batS) multi-layered regression
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BAT批处理程序在图片信息自动处理的辅助应用
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作者 曾柏琛 郭扬 《办公自动化》 2023年第15期62-64,36,共4页
文章介绍BAT批处理程序在图片信息自动处理的辅助应用。通过BAT批处理程序引入图片信息提取技术和自动化处理流程,可以实现图片信息自动分类、自动识别和自动存储等功能,从而减少人工干预和提高工作效率;同时,文章主要研究图片信息自动... 文章介绍BAT批处理程序在图片信息自动处理的辅助应用。通过BAT批处理程序引入图片信息提取技术和自动化处理流程,可以实现图片信息自动分类、自动识别和自动存储等功能,从而减少人工干预和提高工作效率;同时,文章主要研究图片信息自动处理在典型领域的应用场景,设置的场景为无人机输电线路巡检图片信息提取,在提高生产力和降低成本的同时,也为企业带来更快捷的服务和更好的用户体验。最后,指出其在办公自动化中的重要价值和应用前景。 展开更多
关键词 信息自动处理 bat批处理程序 办公自动化 典型领域
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A bat MERS-like coronavirus circulates in pangolins and utilizes human DPP4 and host proteases for cell entry
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作者 Jing Chen 《四川生理科学杂志》 2023年第3期545-545,共1页
It is unknown whether pangolins,the most trafficked mammals,play a role in the zoonotic transmission of bat coronaviruses.We report the circulation of a novel MERS-like coronavirus in Malayan pangolins,named Manis jav... It is unknown whether pangolins,the most trafficked mammals,play a role in the zoonotic transmission of bat coronaviruses.We report the circulation of a novel MERS-like coronavirus in Malayan pangolins,named Manis javanica HKU4-related coronavirus(MjHKU4r-CoV).Among 86 animals,four tested positive by pan-CoV PCR,and seven tested seropositive(11 and 12.8%). 展开更多
关键词 utilize bat CORONAVIRUS
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结内非霍奇金淋巴瘤微卫星位点BAT-26和BAT-25的分析
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作者 平波 孙孟红 +4 位作者 许越香 蔡崎 张太明 陆洪芬 施达仁 《中国癌症杂志》 CAS CSCD 2004年第1期24-27,共4页
目的 :通过微卫星位点BAT 2 6和BAT 2 5的分析 ,探讨结内非霍奇金淋巴瘤是否存在微卫星不稳定性。方法 :收集手术活检所得 51例结内非霍奇金淋巴瘤和 9例淋巴结反应性增生的冷冻标本 ,并分离基因组DNA ,通过PCR法扩增微卫星位点BAT 2 6... 目的 :通过微卫星位点BAT 2 6和BAT 2 5的分析 ,探讨结内非霍奇金淋巴瘤是否存在微卫星不稳定性。方法 :收集手术活检所得 51例结内非霍奇金淋巴瘤和 9例淋巴结反应性增生的冷冻标本 ,并分离基因组DNA ,通过PCR法扩增微卫星位点BAT 2 6和BAT 2 5,应用全自动DNA测序仪和GeneScan 3 .1软件进行片段分析 ,观察这两个位点重复序列长度的变化。以已知遗传性非息肉病性结直肠癌的高度微卫星不稳病例 10例为阳性对照。结果 :扩增成功的标本均未见BAT 2 6或BAT 2 5位点单碱基重复序列大小异常。结论 :采用结直肠肿瘤中高度敏感的微卫星稳定性检测位点BAT 2 6和BAT 2 5,未发现结内非霍奇金淋巴瘤存在高度微卫星不稳 。 展开更多
关键词 非霍奇金淋巴瘤 微卫星分析 bat-26 bat-25
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基于HS-Bat算法的电网负荷卸载协调分配系统设计 被引量:1
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作者 杨立超 李宏梅 +2 位作者 唐涛 张泽 许方杰 《自动化仪表》 CAS 2023年第5期74-77,82,共5页
多电网负荷联合分配后,系统中将产生较多的剩余负荷。为了实现剩余负荷的优化分配,设计了基于和声搜索-蝙蝠(HSBat)算法的电网负荷卸载协调分配系统。硬件设计调整了电网负荷卸载异步数据的接收装置,将时钟点位与异步数据调整为同步状态... 多电网负荷联合分配后,系统中将产生较多的剩余负荷。为了实现剩余负荷的优化分配,设计了基于和声搜索-蝙蝠(HSBat)算法的电网负荷卸载协调分配系统。硬件设计调整了电网负荷卸载异步数据的接收装置,将时钟点位与异步数据调整为同步状态,以提升电网负荷卸载分配精度。软件设计基于HS-Bat计算电网剩余负荷最大值,建立电网负荷分配模型。设定单电网联合分配与多电网联合分配的目标函数,划分整体与局部功率的约束条件,设计电网负荷卸载协调分配算法。以剩余负荷峰谷差和剩余艾伦方差为指标进行性能测试。测试结果表明:设计系统应用后,剩余负荷峰谷差和剩余艾伦方差低于1.4,电网负荷分配效果更好,提高了电网负荷协调分配后的系统稳定性。 展开更多
关键词 和声搜索-蝙蝠算法 电网负荷 协调分配 剩余负荷 时钟点位 局部功率 负荷峰谷 艾伦方差
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改进的Active Bat室内超声波定位方法 被引量:7
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作者 熊剑 周先赞 +1 位作者 郭杭 衷卫声 《探测与控制学报》 CSCD 北大核心 2017年第1期101-105,共5页
针对Active Bat室内超声波位方法中定位精度受环境温度、硬件延时误差、时间同步误差等的影响,提出了改进的Active Bat室内超声波定位方法。该方法在Active Bat室内超声波定位系统结构基础上设立一个参考节点,通过参考节点定位坐标与实... 针对Active Bat室内超声波位方法中定位精度受环境温度、硬件延时误差、时间同步误差等的影响,提出了改进的Active Bat室内超声波定位方法。该方法在Active Bat室内超声波定位系统结构基础上设立一个参考节点,通过参考节点定位坐标与实际位置坐标获取位置误差修正数,修正定位终端定位误差,以提高定位精度。室内环境下进行实验数据采集、解算、对比分析,实验验证表明,常规的Active Bat室内超声波定位定位平均误差为6.93cm;该方法定位平均误差为1.86cm。该方法可以有效提高室内定位精度,定位精度提高了接近73.16%。 展开更多
关键词 ACTIVE bat 超声波定位 误差修正
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IFCO BAT系统测试地基孔压及原位渗透系数理论及其应用 被引量:8
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作者 陈云敏 林政 Schellingerhout A J G 《岩石力学与工程学报》 EI CAS CSCD 北大核心 2005年第24期4440-4448,共9页
渗透系数是直接反映土体渗透性的参数,是土工计算分析中的关键参数,其值的准确求取有重要的工程实际意义。IFCO BAT系统是一套能快速、准确获取地基孔隙水压力和原位渗透系数的先进测试系统。据此,总结介绍IFCO BAT系统测试地基孔隙水... 渗透系数是直接反映土体渗透性的参数,是土工计算分析中的关键参数,其值的准确求取有重要的工程实际意义。IFCO BAT系统是一套能快速、准确获取地基孔隙水压力和原位渗透系数的先进测试系统。据此,总结介绍IFCO BAT系统测试地基孔隙水压力和原位渗透系数的理论,并介绍其在吹填土大型模型槽试验中的应用。实践证明:IFCO BAT系统的渗流分析理论及其渗透系数求取是正确的、合理的,并有很高的工程实用价值。 展开更多
关键词 基础工程 IFCO bat系统 现场测试 孔隙水压力 地基原位渗透系数 渗流分析理论 流阻
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用 BATS 模型模拟径流的个例研究 被引量:4
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作者 刘春蓁 程斌 +1 位作者 程兴无 章四龙 《水文》 CSCD 北大核心 1998年第1期8-13,共6页
为了解陆气间水热交换在径流形成中的作用,本文采用BATS模型模拟了淮河流域山区和平原在1991年汛期50天的暴雨洪水过程,计算了径流,土壤温度和感热,潜热通量,并用常规的汇流计算方法得到了流域出口断面的流量过程线。为... 为了解陆气间水热交换在径流形成中的作用,本文采用BATS模型模拟了淮河流域山区和平原在1991年汛期50天的暴雨洪水过程,计算了径流,土壤温度和感热,潜热通量,并用常规的汇流计算方法得到了流域出口断面的流量过程线。为了集总地考虑地形(山区及平原)对径流的影响,对径流表达式中的指数“n”进行了修正。计算结果表明:50天洪水总量计算误差较小,模拟洪水的洪峰流量与峰现时间与实况相近,径流值的模拟精度与土壤表层温度的模拟精度紧密相关。所有这些说明径流模拟精度的提高是改进陆面对大气的感热、潜热通量计算的一个重要方面。 展开更多
关键词 batS模型 陆气水热交换 径流模拟 河流
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MM5BATS对东亚夏季气候及其变化的模拟试验 被引量:6
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作者 汤剑平 赵鸣 +1 位作者 苏炳凯 赵得明 《高原气象》 CSCD 北大核心 2005年第1期28-37,共10页
将陆面过程模式BATS耦合到中尺度模式 MM5V3 中与另一区域气候模式 RegCM2 一起对1995-2000年夏季东亚的区域气候作了模拟试验, 并与实际资料作了比较。模拟试验结果表明: (1)两个模式均能较合理地模拟出6年夏季平均的环流、温度和海平... 将陆面过程模式BATS耦合到中尺度模式 MM5V3 中与另一区域气候模式 RegCM2 一起对1995-2000年夏季东亚的区域气候作了模拟试验, 并与实际资料作了比较。模拟试验结果表明: (1)两个模式均能较合理地模拟出6年夏季平均的环流、温度和海平面气压等的变化, MM5BATS的模拟结果要略优于RegCM2的结果; (2)MM5BATS模式较合理地模拟出了 6 年夏季平均的降水分布, 而RegCM2模式的模拟结果偏强; (3)MM5BATS模式较好地模拟出了 1997 年和 1998 年夏季环流场的变化, 对降水的模拟也比较合理。RegCM2对1997年和 1998 年降水的模拟基本上都偏强。模拟试验结果还表明, 在区域气候模拟中有必要采用更新的模式。 展开更多
关键词 MM5batS 区域气候模式 陆面过程
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陆面过程模式BATS中地气通量计算方案的一个改进试验 被引量:2
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作者 陈潜 赵鸣 +1 位作者 汤剑平 苏炳凯 《南京大学学报(自然科学版)》 CAS CSCD 北大核心 2004年第3期330-340,共11页
 在原有的陆面过程模式BATS中,对地表通量的计算基于简单的经验公式,这个计算是十分粗略的.而地气通量对各个气象要素的模拟都很重要,如动量通量会影响大气中的风速分布,热量通量会影响垂直方向上的温度分布而改变大气的层结稳定度,水...  在原有的陆面过程模式BATS中,对地表通量的计算基于简单的经验公式,这个计算是十分粗略的.而地气通量对各个气象要素的模拟都很重要,如动量通量会影响大气中的风速分布,热量通量会影响垂直方向上的温度分布而改变大气的层结稳定度,水汽通量则会改变空气中的水分含量和潜热,因而改进地气通量的计算精度是有必要的.为了提高地─气间通量计算的精度,在模式中增加稳定度的分类,将近地层稳定度分为5类,用中尺度气候模式RIEMS,分别对短期和中期模拟作了对比实验.经过比较和分析模拟结果,可以看出在增加稳定度的分类以后,模拟的各个气象要素场都较原来的有了改善. 展开更多
关键词 batS 稳定度 中尺度气候模式 地气通量 陆面过程模式
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我国互联网企业智库成果量化分析——以百度、阿里巴巴、腾讯(BAT)为例 被引量:5
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作者 丁炫凯 徐致远 《图书馆论坛》 CSSCI 北大核心 2016年第5期17-24,共8页
文章通过量化分析2011-2015年百度、阿里巴巴、腾讯(BAT)智库成果,展现我国互联网企业智库发展现状,分析我国互联网企业智库在资金、技术、体制、传播等方面的发展潜力,以及存在的问题,并对互联网企业智库发展提出建议。
关键词 互联网企业 智库 bat 百度 阿里巴巴 腾讯
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