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Automatic velocity picking based on optimal key points tracking algorithm
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作者 Yong-Hao Wang Wen-Kai Lu +3 位作者 Song-Bai Jin Yang Li Yu-Xuan Li Xiao-Feng Gu 《Petroleum Science》 SCIE EI CAS CSCD 2024年第2期903-917,共15页
Picking velocities from semblances manually is laborious and necessitates experience. Although various methods for automatic velocity picking have been developed, there remains a challenge in efficiently incorporating... Picking velocities from semblances manually is laborious and necessitates experience. Although various methods for automatic velocity picking have been developed, there remains a challenge in efficiently incorporating information from nearby gathers to ensure picked velocity aligns with seismic horizons while also improving picking accuracy. The conventional method of velocity picking from a semblance volume is computationally demanding, highlighting a need for a more efficient strategy. In this study, we introduce a novel method for automatic velocity picking based on multi-object tracking. This dynamic tracking process across different semblance panels can integrate information from nearby gathers effectively while maintaining computational efficiency. First, we employ accelerated density clustering on the velocity spectrum to discern cluster centers without the requirement for prior knowledge regarding the number of clusters. These cluster centers embody the maximum likelihood velocities of the main subsurface structures. Second, our proposed method tracks key points within the semblance volume. Kalman filter is adopted to adjust the tracking process, followed by interpolation on these tracked points to construct the final velocity model. Our synthetic data example demonstrates that our proposed algorithm can effectively rectify the picking errors of the clustering algorithm. We further compare the performances of the clustering method(CM), the proposed tracking method(TM), and the variational method(VM) on a field dataset from the Gulf of Mexico. The results attest that our method offers superior accuracy than CM, achieves comparable accuracy with VM, and benefits from a reduced computational cost. 展开更多
关键词 Velocity picking Multi-object tracking Density clustering Kalman filter
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Manual Order Picking Route Optimization in Distribution Warehouse of Chain Furniture Retail Enterprise
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作者 Yongzhen Zeng Junkun Wang +1 位作者 Ching-Kuei Kao King-Zoo Tang 《American Journal of Operations Research》 2024年第3期105-136,共32页
Due to the effects of the COVID-19 pandemic and the rise of online shopping, the offline sales of IKEA Fuzhou have been declining since 2020. Because the cost of distribution warehouse is a major expense for offline c... Due to the effects of the COVID-19 pandemic and the rise of online shopping, the offline sales of IKEA Fuzhou have been declining since 2020. Because the cost of distribution warehouse is a major expense for offline chain furniture retailers, and the picking process is a key activity in distribution warehouse operations. To reduce the cost of distribution warehouse and alleviate the survival pressure of the offline chain furniture retailers, this paper focuses on optimizing the picking route of the IKEA Fuzhou distribution warehouse. It starts by creating a two-dimensional coordinate system for the storage location of the distribution warehouse using the traditional S-type picking strategy to calculate the distance and time of the sorting route. Then, the problem of optimizing the picking route is then transformed into the travelling salesman problem (TSP), and picking route optimization model is developed using a genetic algorithm to analyze the sorting efficiency and picking route optimization. Results show that the order-picking route using the genetic algorithm strategy is significantly better than the traditional S-type picking strategy, which can improve overall sorting efficiency and operations, reduce costs, and increase efficiency. Thus, this establishes an implementation process for the order-picking path based on genetic algorithm optimization to improve overall sorting efficiency and operations, reduce costs, increase efficiency, and alleviate the survival pressure of pandemic-affected enterprises. 展开更多
关键词 S-Shaped picking Strategy picking Route Traveling Salesman Problem Genetic Algorithm
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Basic Research on the Burden of Dropping off and Picking up Children: Differences by Employment Type and Gender in the Tokyo Metropolitan Area
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作者 Jun Morio Koshi Isono +1 位作者 Masahiko Kikuchi Tetsuo Morita 《Journal of Transportation Technologies》 2024年第3期445-461,共17页
There is a need to reduce the burden of child drop-off and pick-up for child-rearing generations, but most studies on the actual situation in Japan are based on survey results. In this study, we analyzed differences i... There is a need to reduce the burden of child drop-off and pick-up for child-rearing generations, but most studies on the actual situation in Japan are based on survey results. In this study, we analyzed differences in child drop-off and pick-up by employment type and gender, utilizing the “Metropolitan Area Person Trip Survey,” which is a statistical data set. The study targeted households in which both spouses were between 30 and 49 years old, had children under the age of 6, and included the following three groups. 1) Dual-income Group 1 (both spouses employed/on contract/temporary);2) Dual-income Group 2 (husband employed/on contract/temporary, wife part-time);3) Full-time housewife group (husband employed, wife unemployed). The analysis revealed that a) wives are almost always responsible for dropping off and picking up their children;b) husbands drop off and pick up their children less frequently in dual-income households;and c) households with children raising within 10 to 30 km of Tokyo Station have longer commuting times and need to reduce the burden of dropping off and picking up their children. 展开更多
关键词 Drop-Off and pick-Up Employment Type GENDER Dual-Income Households Tokyo Metropolitan Area
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Niemann-Pick C1蛋白在埃博拉病毒感染中的作用及其靶向药物研究进展
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作者 吴海燕 陈国江 《中国药理学与毒理学杂志》 CAS 北大核心 2024年第2期153-160,共8页
埃博拉病毒属丝状病毒科,具有高传染性,能引起人类和灵长类动物出现严重出血热等症状,病死率高达90%。Niemann-Pick C1(NPC1)蛋白是埃博拉病毒感染过程中表达于宿主细胞内体膜上的一个重要受体,其与埃博拉病毒被组织蛋白酶裂解的糖蛋白(... 埃博拉病毒属丝状病毒科,具有高传染性,能引起人类和灵长类动物出现严重出血热等症状,病死率高达90%。Niemann-Pick C1(NPC1)蛋白是埃博拉病毒感染过程中表达于宿主细胞内体膜上的一个重要受体,其与埃博拉病毒被组织蛋白酶裂解的糖蛋白(GP)的相互作用是病毒感染宿主的关键环节,介导病毒囊膜与内体膜的融合,进而将病毒基因组释放到宿主细胞。近年来,将NPC1蛋白作为广谱抗丝状病毒药物靶点研发的小分子抑制剂、单克隆抗体和基因治疗药物均有突破性进展。本文介绍了NPC1的结构及其在埃博拉病毒感染中的作用,并对靶向NPC1的小分子抑制剂、单克隆抗体药物和基因治疗药物的研究现状进行总结。 展开更多
关键词 埃博拉病毒 Niemann-pick C1蛋白 小分子抑制剂 抗体 基因治疗
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COMPRESSIBLE VIRTUAL WINDOW ALGORITHM IN PICKING PROCESS CONTROL OF AUTOMATED SORTING SYSTEM 被引量:15
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作者 WU Yaohua ZHANG Yigong WU Yingying 《Chinese Journal of Mechanical Engineering》 SCIE EI CAS CSCD 2008年第3期41-45,共5页
Compared to fixed virtual window algorithm (FVWA), the dynamic virtual window algorithm (DVWA) determines the length of each virtual container according to the sizes of goods of each order, which saves space of vi... Compared to fixed virtual window algorithm (FVWA), the dynamic virtual window algorithm (DVWA) determines the length of each virtual container according to the sizes of goods of each order, which saves space of virtual containers and improves the picking efficiency. However, the interval of consecutive goods caused by dispensers on conveyor can not be eliminated by DVWA, which limits a further improvement of picking efficiency. In order to solve this problem, a compressible virtual window algorithm (CVWA) is presented. It not only inherits the merit of DVWA but also compresses the length of virtual containers without congestion of order accumulation by advancing the beginning time of order picking and reasonably coordinating the pace of order accumulation. The simulation result proves that the picking efficiency of automated sorting system is greatly improved by CVWA. 展开更多
关键词 Virtual window algorithm Dynamics COMPRESSIBILITY picking efficiency
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Multiple People Picking Assignment and Routing Optimization Based on Genetic Algorithm
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作者 孙慧 《科技视界》 2014年第1期26-27,57,共3页
In order to improve the picking efficiency,reduce the picking time,this paper take artificial picking operation of a certain distribution center which has double-area warehouse as the studying object.Discuss the picki... In order to improve the picking efficiency,reduce the picking time,this paper take artificial picking operation of a certain distribution center which has double-area warehouse as the studying object.Discuss the picking task allocation and routing problems.Establish the TSP model of order-picking system.Create a heuristic algorithm bases on the Genetic Algorithm(GA)which help to solve the task allocating problem and to get the associated order-picking routes.And achieve the simulation experiment with the Visual 6.0C++platform to prove the rationality of the model and the effectiveness of the arithmetic. 展开更多
关键词 拣选效率 采收期 遗传算法 计算方法
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ORDER-PICKING OPTIMIZATION FOR AUTOMATED PICKING SYSTEM WITH PARALLEL DISPENSERS 被引量:7
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作者 WU Yaohua ZHANG Yigong 《Chinese Journal of Mechanical Engineering》 SCIE EI CAS CSCD 2008年第6期25-29,共5页
Based on the characteristics of parallel dispensers in automated picking system, an order-picking optimization problem is presented. Firstly, the working principle of parallel dispensers is introduced, which implies t... Based on the characteristics of parallel dispensers in automated picking system, an order-picking optimization problem is presented. Firstly, the working principle of parallel dispensers is introduced, which implies the time cost of picking each order is influenced by the order-picking sequence. So the order-picking optimization problem can be classified as a dynamic traveling salesman problem (TSP). Then a mathematical model of the problem is established and an improved max-min ant system (MMAS) is adopted to solve the model. The improvement includes two aspects. One is that the initial assignment of ants depends on a probabilistic formula instead of a random deployment; the other is that the heuristic factor is expressed by the extra picking time of each order instead of the total. At last, an actual simulation is made on an automated picking system with parallel dispensers. The simulation results proved the optimization value and the validity of improvement on MMAS. 展开更多
关键词 Automated picking system Parallel dispensers Max-min ant system
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Fluid-based Slotting Optimization for Automated Order Picking System with Multiple Dispenser Types 被引量:5
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作者 LIU Peng WU Yaohua +1 位作者 ZHOU Chen XU Na 《Chinese Journal of Mechanical Engineering》 SCIE EI CAS CSCD 2011年第4期529-538,共10页
Slotting strategy heavily influences the throughput and operational cost of automated order picking system with multiple dispenser types, which is called the complex automated order picking system (CAOPS). Existing ... Slotting strategy heavily influences the throughput and operational cost of automated order picking system with multiple dispenser types, which is called the complex automated order picking system (CAOPS). Existing research either focuses on one aspect of the slotting optimization problem or only considers one part of CAOPS, such as the Low-volume Dispensers, to develop corresponding slotting strategies. In order to provide a comprehensive and systemic approach, a fluid-based slotting strategy is proposed in this paper. The configuration of CAOPS is presented with specific reference to its fast-picking and restocking subsystems. Based on extended fluid model, a nonlinear mathematical programming model is developed to determine the optimal volume allotted to each stock keeping unit (SKU) in a certain mode by minimize the restocking cost of that mode. Conclusion from the allocation model is specified for the storage modules of high-volume dispensers and low-volume dispensers. Optimal allocation of storage resources in the fast-picking area of CAOPS is then discussed with the aim of identifying the optimal space of each picking mode. The SKU assignment problem referring to the total restocking cost of CAOPS is analyzed and a greedy heuristic with low time complexity is developed according to the characteristics of CAOPS. Real life application from the tobacco industry is presented in order to exemplify the proposed slotting strategy and assess the effectiveness of the developed methodology. Entry-item-quantity (EIQ) based experiential solutions and proposed-model-based near-optimal solutions are compared. The comparison results show that the proposed strategy generates a savings of over 18% referring to the total restocking cost over one-year period. The strategy proposed in this paper, which can handle the multiple dispenser types, provides a practical quantitative slotting method for CAOPS and can help picking-system-designers make slotting decisions efficiently and effectively. 展开更多
关键词 SLOTTING complex automated order picking system restocking cost DISPENSER
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Taboo Search Algorithm for Item Assignment in Synchronized Zone Automated Order Picking System 被引量:2
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作者 WU Yingying WU Yaohua 《Chinese Journal of Mechanical Engineering》 SCIE EI CAS CSCD 2014年第4期860-866,共7页
The idle time which is part of the order fulfillment time is decided by the number of items in the zone; therefore the item assignment method affects the picking efficiency. Whereas previous studies only focus on the ... The idle time which is part of the order fulfillment time is decided by the number of items in the zone; therefore the item assignment method affects the picking efficiency. Whereas previous studies only focus on the balance of number of kinds of items between different zones but not the number of items and the idle time in each zone. In this paper, an idle factor is proposed to measure the idle time exactly. The idle factor is proven to obey the same vary trend with the idle time, so the object of this problem can be simplified from minimizing idle time to minimizing idle factor. Based on this, the model of item assignment problem in synchronized zone automated order picking system is built. The model is a form of relaxation of parallel machine scheduling problem which had been proven to be NP-complete. To solve the model, a taboo search algorithm is proposed. The main idea of the algorithm is minimizing the greatest idle factor of zones with the 2-exchange algorithm. Finally, the simulation which applies the data collected from a tobacco distribution center is conducted to evaluate the performance of the algorithm. The result verifies the model and shows the algorithm can do a steady work to reduce idle time and the idle time can be reduced by 45.63% on average. This research proposed an approach to measure the idle time in synchronized zone automated order picking system. The approach can improve the picking efficiency significantly and can be seen as theoretical basis when optimizing the synchronized automated order picking systems. 展开更多
关键词 taboo search algorithm synchronized zone order picking idle time idle factor
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Comparative experimental analysis on various picking types under dedicated and random storage assignments for automated storage and retrieval systems 被引量:1
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作者 王坤 HE Fang +2 位作者 张光远 JIANG Shan GONG Di 《Journal of Chongqing University》 CAS 2018年第3期101-118,共18页
Product storage policy, single picking volume and picking routing are the three factors of vital importance that affect the efficiency of a crane to pick goods in automated storage and retrieval systems(AS/RS). Compar... Product storage policy, single picking volume and picking routing are the three factors of vital importance that affect the efficiency of a crane to pick goods in automated storage and retrieval systems(AS/RS). Comparative experiments on picking efficiency were conducted targeting picking operation with order of 1 to 20. Based on dedicated and random storage policies, 4 picking methods of patching-based, S-type, return-type and optimized-type routes were used and compared in the experiments. The results show that either the dedicated policy or the random policy was applied, crane worked most efficiently with optimizedtype route, followed by S-type path, patching-based path, and return-type path. When the number of orders in a single picking is larger(more than 5), the random storage policy is preferable to the dedicated policy. 展开更多
关键词 dedicated storage policy random storage policy patching-based picking S-type picking return-type picking optimized-type picking
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Active Source Seismic Identification and Automatic Picking of the P-wave First Arrival Using a Convolutional Neural Network 被引量:3
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作者 XU Zhen WANG Tao +4 位作者 XU Shanhui WANG Baoshan FENG Xuping SHI Jing YANG Minghan 《Earthquake Research in China》 CSCD 2019年第2期288-304,共17页
In seismic data processing,picking of the P-wave first arrivals takes up plenty of time and labor,and its accuracy plays a key role in imaging seismic structures.Based on the convolution neural network(CNN),we propose... In seismic data processing,picking of the P-wave first arrivals takes up plenty of time and labor,and its accuracy plays a key role in imaging seismic structures.Based on the convolution neural network(CNN),we propose a new method to pick up the P-wave first arrivals automatically.Emitted from MINI28 vibroseis in the Jingdezhen seismic experiment,the vertical component of seismic waveforms recorded by EPS 32-bit portable seismometers are used for manually picking up the first arrivals(a total of 7242).Based on these arrivals,we establish the training and testing sets,including 25,290 event samples and 710,616 noise samples(length of each sample:2 s).After 3,000 steps of training,we obtain a convergent CNN model,which can automatically classify seismic events and noise samples with high accuracy(>99%).With the trained CNN model,we scan continuous seismic records and take the maximum output(probability of a seismic event)as the P-wave first arrival time.Compared with STA/LTA(short time average/long time average),our method shows higher precision and stronger anti-noise ability,especially with the low SNR seismic data.This CNN method is of great significance for promoting the intellectualization of seismic data processing,improving the resolution of seismic imaging,and promoting the joint inversion of active and passive sources. 展开更多
关键词 CNN Active source SEISMIC identification FIRST ARRIVAL picking ANTI-NOISE ability
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Locating Famous Tea’s Picking Point Based on Shi-Tomasi Algorithm 被引量:1
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作者 Lei Zhang Lang Zou +2 位作者 Chuanyu Wu Jianneng Chen Heping Chen 《Computers, Materials & Continua》 SCIE EI 2021年第10期1109-1122,共14页
To address the difficulty of locating the picking point of a tea sprout during the intelligent automatic picking of famous tea,this study proposes a method to obtain information on the picking point on the basis of th... To address the difficulty of locating the picking point of a tea sprout during the intelligent automatic picking of famous tea,this study proposes a method to obtain information on the picking point on the basis of the ShiTomasi algorithm.This method can rapidly identify a tea sprout’s picking point and obtain its coordinates.Images of tea sprouts in a tea garden were collected,and the G-B component of tea sprouts was segmented using the Otsu algorithm.The region of interest was set with the lowest point of its contour as the center.The characteristics of tea buds and branches in the area were extracted,and the Otsu algorithm was used for a second segmentation of tea sprout images.The tea buds were segmented using the improved Zhang algorithm.The branch feature binary image was used to refine the skeleton,and the Shi-Tomasi algorithm was used to detect the corners of the skeleton and calculate and mark the picking points of the shoots.Sixty sets of samples were tested.The test identified 1,042 effective shoots for tender buds,and 887 picking points were marked,with a success rate of 85.12%,thereby verifying the effectiveness of the method and providing a theoretical reference for the visual positioning of the automatic picking of famous tea. 展开更多
关键词 Famous tea picking location Zhang algorithm Shi-Tomasi algorithm
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SegNet-based first-break picking via seismic waveform classification directly from shot gathers with sparsely distributed traces 被引量:1
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作者 San-Yi Yuan Yue Zhao +2 位作者 Tao Xie Jie Qi Shang-Xu Wang 《Petroleum Science》 SCIE CAS CSCD 2022年第1期162-179,共18页
Manually picking regularly and densely distributed first breaks(FBs)are critical for shallow velocitymodel building in seismic data processing.However,it is time consuming.We employ the fullyconvolutional Seg Net to a... Manually picking regularly and densely distributed first breaks(FBs)are critical for shallow velocitymodel building in seismic data processing.However,it is time consuming.We employ the fullyconvolutional Seg Net to address this issue and present a fast automatic seismic waveform classification method to pick densely-sampled FBs directly from common-shot gathers with sparsely distributed traces.Through feeding a large number of representative shot gathers with missing traces and the corresponding binary labels segmented by manually interpreted fully-sampled FBs,we can obtain a welltrained Seg Net model.When any unseen gather including the one with irregular trace spacing is inputted,the Seg Net can output the probability distribution of different categories for waveform classification.Then FBs can be picked by locating the boundaries between one class on post-FBs data and the other on pre-FBs background.Two land datasets with each over 2000 shots are adopted to illustrate that one well-trained 25-layer Seg Net can favorably classify waveform and further pick fully-sampled FBs verified by the manually-derived ones,even when the proportion of randomly missing traces reaches50%,21 traces are missing consecutively,or traces are missing regularly. 展开更多
关键词 First-break picking Deep learning Irregular seismic data Waveform classification
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Applying the Method for Solving Traveling Salesman Problem Based on Backtracking Algorithm to Order Picking 被引量:1
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作者 Jie Zhu Ying Huang Lijuan Xu 《Open Journal of Optimization》 2016年第2期84-89,共6页
In the distribution center, the way of order picking personnel to pick goods has two kinds: single picking and batch picking. Based on the way of the single picking and assumed warehouse model, in order to reduce the ... In the distribution center, the way of order picking personnel to pick goods has two kinds: single picking and batch picking. Based on the way of the single picking and assumed warehouse model, in order to reduce the walking path of order picking, the order picking problem is transformed into the traveling salesman problem in this paper. Based on backtracking algorithm, the order picking path gets optimized. Finally verifing the optimization method under the environment of VC++6.0, order picking path in the warehouse model get optimized, and compared with the traditional order picking walking paths. The results show that in small and medium-sized warehouse, the optimization method proposed in this paper can reduce order picking walking path and improve the work efficiency as well as reduce the time cost. 展开更多
关键词 Single picking Path Optimization Traveling Salesman Problem Backtracking Algorithm
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Application of Machine Learning Methods in Arrival Time Picking of P Waves from Reservoir Earthquakes 被引量:1
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作者 HU Jiupeng YU Ziye +3 位作者 KUANG Wenhuan WANG Weitao RUAN Xiang DAI Shigui 《Earthquake Research in China》 CSCD 2020年第3期343-357,共15页
Reservoir earthquake characteristics such as small magnitude and large quantity may result in low monitoring efficiency when using traditional methods.However,methods based on deep learning can discriminate the seismi... Reservoir earthquake characteristics such as small magnitude and large quantity may result in low monitoring efficiency when using traditional methods.However,methods based on deep learning can discriminate the seismic phases of small earthquakes in a reservoir and ensure rapid processing of arrival time picking.The present study establishes a deep learning network model combining a convolutional neural network(CNN) and recurrent neural network(RNN).The neural network training uses the waveforms of 60 000 small earthquakes within a magnitude range of 0.8-1.2 recorded by 73 stations near the Dagangshan Reservoir in Sichuan Province as well as the data of the manually picked P-wave arrival time.The neural network automatically picks the P-wave arrival time,providing a strong constraint for small earthquake positioning.The model is shown to achieve an accuracy rate of 90.7 % in picking P waves of microseisms in the reservoir area,with a recall rate reaching 92.6% and an error rate lower than 2%.The results indicate that the relevant network structure has high accuracy for picking the P-wave arrival times of small earthquakes,thus providing new technical measures for subsequent microseismic monitoring in the reservoir area. 展开更多
关键词 Deep Learning Phase pick Reservoir Microseismic
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USTC-Pickers:a Unified Set of seismic phase pickers Transfer learned for China 被引量:5
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作者 Jun Zhu Zefeng Li Lihua Fang 《Earthquake Science》 2023年第2期95-112,共18页
Current popular deep learning seismic phase pickers like PhaseNet and EQTransformer suffer from performance drop in China.To mitigate this problem,we build a unified set of customized seismic phase pickers for differe... Current popular deep learning seismic phase pickers like PhaseNet and EQTransformer suffer from performance drop in China.To mitigate this problem,we build a unified set of customized seismic phase pickers for different levels of use in China.We first train a base picker with the recently released DiTing dataset using the same U-Net architecture as PhaseNet.This base picker significantly outperforms the original PhaseNet and is generally suitable for entire China.Then,using different subsets of the DiTing data,we fine-tune the base picker to better adapt to different regions.In total,we provide 5 pickers for major tectonic blocks in China,33 pickers for provincial-level administrative regions,and 2 special pickers for the Capital area and the China Seismic Experimental Site.These pickers show improved performance in respective regions which they are customized for.They can be either directly integrated into national or regional seismic network operation or used as base models for further refinement for specific datasets.We anticipate that this picker set will facilitate earthquake monitoring in China. 展开更多
关键词 phase picking transfer learning model customization
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Motion Planning System for Bin Picking Using 3-D Point Cloud 被引量:1
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作者 Masatoshi Hikizu Shu Mikami Hiroaki Seki 《Intelligent Control and Automation》 2016年第3期73-83,共12页
In this paper, we propose a motion planning system for bin picking using 3-D point cloud. The situation that the objects are put miscellaneously like the inside in a house is assumed. In the home, the equipment which ... In this paper, we propose a motion planning system for bin picking using 3-D point cloud. The situation that the objects are put miscellaneously like the inside in a house is assumed. In the home, the equipment which makes an object stand in line doesn’t exist. Therefore the motion planning system which considered a collision problem becomes important. In this paper, Information on the objects is measured by a laser range finder (LRF). The information is used as 3-D point cloud, and the objects are recognized by model-base. We propose search method of a grasping point for two-fingered robotic hand, and propose search method of a path to approach the grasping point without colliding with other objects. 展开更多
关键词 3-D Point Cloud Bin picking ICP Algorithm Motion Planning
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Intelligent Control Mechanism of Part Picking Operations of Automated Warehouse
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作者 Chwen-Tzeng Su 《厦门大学学报(自然科学版)》 CAS CSCD 北大核心 2002年第S1期109-110,共2页
This paper studies the part picking operations of a ut omated warehouse. It assumed the demand of picking orders of automated warehouse are dynamic generated. Once the picking orders of certain period of time are kn o... This paper studies the part picking operations of a ut omated warehouse. It assumed the demand of picking orders of automated warehouse are dynamic generated. Once the picking orders of certain period of time are kn own, it is necessary to decide an efficient order picking sequence and routing t o minimize the total travel distance to complete those orders. Assumed there are n i items to be picked in order O i. Each item in the picking ord er is located in different locations in the warehouse. Since it is possible the same items appear in the different picking orders, it will reduce the picking di stance if these orders can be batched and picked in one path. However, there are several constraints for the order batching and order picking operations. These constraint are (1) the crane of the automated warehouse has the carrying capacit y of C, and (2) for the management convenience, it is assumed that one picki ng order must be completed in one path. Because of the complexity of problem, it is inefficient to solve the problem by analytical approach. Although the heuristic method can significantly reduce of the computation time, the quality of the solution is always unacceptable. It is the intention of this paper to integrate the advantages of neural network and simulated annealing technique to develop the control mechanism for the planning of order picking operations of automated warehouse. A systematic computational simulation is conducted to evaluate the proposed method. The results show the pr oposed method can generate superior solution in most cased. 展开更多
关键词 order picking order batching neural network mod el simulated annealing
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P wave onset time picking with the B-spline biorthogonal wavelet
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作者 滕云田 王喜珍 +2 位作者 王晓美 马洁美 许建华 《Acta Seismologica Sinica(English Edition)》 CSCD 2006年第3期350-355,共6页
The seismic wave consists of many seismic phases, which contain rich geophysical information from the hypocenter, medium of seismic wave passing through and so on. It is very important to detect and pick these seismic... The seismic wave consists of many seismic phases, which contain rich geophysical information from the hypocenter, medium of seismic wave passing through and so on. It is very important to detect and pick these seismic phases for understanding the mechanism of earthquake, the Earth structure and property of seismic waves. In order to reduce or avoid the loss resulted from the earthquake, one of the important goals of seismic event detecting is to obtain its related information before and after it occurs. Because of the particularity of P wave and S wave the seismic event detecting focuses on distinguishing P and S waves and picking their onset time, it has been becoming one of the research hotspots for many geophysicists to pick the P and S wave arrival accurately and effectively. 展开更多
关键词 biorthogonal wavelet characteristic function the onset time picking
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Enhancing manual P-phase arrival detection and automatic onset time picking in a noisy microseismic data in underground mines 被引量:4
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作者 Mborah Charles Ge Maochen 《International Journal of Mining Science and Technology》 EI CSCD 2018年第4期683-691,共9页
Accurate detection and picking of the P-phase onset time in noisy microseismic data from underground mines remains a big challenge. Reliable P-phase onset time picking is necessary for accurate source location needed ... Accurate detection and picking of the P-phase onset time in noisy microseismic data from underground mines remains a big challenge. Reliable P-phase onset time picking is necessary for accurate source location needed for planning and rescue operations in the event of failures. In this paper, a new technique based on the discrete stationary wavelet transform(DSWT) and higher order statistics is proposed for processing noisy data from underground mines. The objectives of this method are to(i) improve manual detection and picking of P-phase onset; and(ii) provide an automatic means of detecting and picking P-phase onset time accurately. The DSWT is first used to filter the signal over several scales. The manual P-phase onset detection and picking are then obtained by computing the signal energy across selected scales with frequency bands that capture the signal of interest. The automatic P-phase onset, on the other hand, is achieved by using skewness-and kurtosis-based criterion applied to selected scales in a time-frequency domain. The method was tested using synthetic and field data from an underground limestone mine. Results were compared with results obtained by using the short-term to long-term average(STA/LTA) ratio and that by Reference Ge et al.(2009). The results show that the method provides a more reliable estimate of the P-phase onset arrival than the STA/LTA method when the signal to noise ratio is very low. Also, the results obtained from the field data matched accurately with the results from Reference Ge et al.(2009). 展开更多
关键词 时间频率 顺序统计 石灰石矿 数据获得 信号 偏斜度 参考书 STA
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