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Non-state Investment Picking Up
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作者 Ru Qing 《China's Foreign Trade》 2000年第11期28-28,共1页
关键词 In Non-state Investment picking up
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A regression approach for seismic first-break picking
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作者 Huan Yuan San-Yi Yuan +2 位作者 Jie Wu Wen-Jing Sang Yu-He Zhao 《Petroleum Science》 SCIE EI CAS CSCD 2024年第3期1584-1596,共13页
The picking efficiency of seismic first breaks(FBs)has been greatly accelerated by deep learning(DL)technology.However,the picking accuracy and efficiency of DL methods still face huge challenges in low signal-to-nois... The picking efficiency of seismic first breaks(FBs)has been greatly accelerated by deep learning(DL)technology.However,the picking accuracy and efficiency of DL methods still face huge challenges in low signal-to-noise ratio(SNR)situations.To address this issue,we propose a regression approach to pick FBs based on bidirectional long short-term memory(Bi LSTM)neural network by learning the implicit Eikonal equation of 3D inhomogeneous media with rugged topography in the target region.We employ a regressive model that represents the relationships among the elevation of shots,offset and the elevation of receivers with their seismic traveltime to predict the unknown FBs,from common-shot gathers with sparsely distributed traces.Different from image segmentation methods which automatically extract image features and classify FBs from seismic data,the proposed method can learn the inner relationship between field geometry and FBs.In addition,the predicted results by the regressive model are continuous values of FBs rather than the discrete ones of the binary distribution.The picking results of synthetic data shows that the proposed method has low dependence on label data,and can obtain reliable and similar predicted results using two types of label data with large differences.The picking results of9380 shots for 3D seismic data generated by vibroseis indicate that the proposed method can still accurately predict FBs in low SNR data.The subsequent stacked profiles further illustrate the reliability and effectiveness of the proposed method.The results of model data and field seismic data demonstrate that the proposed regression method is a robust first-break picker with high potential for field application. 展开更多
关键词 First-break picking Low signal-to-noiseratio Regression BiLSTM TRAVELTIME Geometry Noisy seismic data
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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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First-Arrival Picking Method for Active Source Data with Ocean Bottom Seismometers Based on Spatial Waveform Variation Characteristics
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作者 LIU Hongwei XING Lei +3 位作者 ZHU Henghua ZHANG Jin ZHANG Jing LIU Huaishan 《Journal of Ocean University of China》 SCIE CAS CSCD 2024年第4期970-980,共11页
The precision and reliability of first-arrival picking are crucial for determining the accuracy of geological structure inversion using active source ocean bottom seismometer(OBS)refraction data.Traditional methods fo... The precision and reliability of first-arrival picking are crucial for determining the accuracy of geological structure inversion using active source ocean bottom seismometer(OBS)refraction data.Traditional methods for first-arrival picking based on sample points are characterized by theoretical errors,especially in low-sampling-frequency OBS data because the travel time of seismic waves is not an integer multiple of the sampling interval.In this paper,a first-arrival picking method that utilizes the spatial waveform variation characteristics of active source OBS data is presented.First,the distribution law of theoretical error is examined;adjacent traces exhibit variation characteristics in their waveforms.Second,a label cross-correlation superposition method for extracting highfrequency signals is presented to enhance the first-arrival picking precision.Results from synthetic and field data verify that the proposed approach is robust,successfully overcomes the limitations of low sampling frequency,and achieves precise outcomes that are comparable with those of high-sampling-frequency data. 展开更多
关键词 first-arrival picking spatial waveform variation label cross-correlation superposition method
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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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Pick-up strategies for and electrical characterization of ZnO nanowires with a SEM-based nanomanipulator 被引量:1
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作者 Mei Liu Lingdi Kong +5 位作者 Weilin Su Aristide Djoulde Kai Cheng Jinbo Chen Jinjun Rao Zhiming Wang 《Nanotechnology and Precision Engineering》 CAS CSCD 2023年第1期26-31,共6页
Because of their unique mechanical and electrical properties,zinc oxide(ZnO)nanowires are used widely in microscopic and nanoscopic devices and structures,but characterizing them remains challenging.In this paper,two ... Because of their unique mechanical and electrical properties,zinc oxide(ZnO)nanowires are used widely in microscopic and nanoscopic devices and structures,but characterizing them remains challenging.In this paper,two pick-up strategies are proposed for characterizing the electrical properties of ZnO nanowires using SEM equipped with a nanomanipulator.To pick up nanowires efficiently,direct sampling is compared with electrification fusing,and experiments show that direct sampling is more stable while electrification fusing is more efficient.ZnO nanowires have cut-off properties,and good Schottky contact with the tungsten probes was established.In piezoelectric experiments,the maximum piezoelectric voltage generated by an individual ZnO nanowire was 0.07 V,and its impedance decreased with increasing input signal frequency until it became stable.This work offers a technical reference for the pick-up and construction of nanomaterials and nanogeneration technology. 展开更多
关键词 ZnO nanowires nanomanipulator picking up strategy piezoelectric properties electrical characterization
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Picking up the Pieces
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作者 HUANG WEI 《Beijing Review》 2008年第23期11-11,共1页
Despite hardship and suffering,many quake survivors remain generous and optimistic Liu Jing’s hometown,Xiangxi Village in Anxian County,Sichuan Province,was a picturesque place, in an area known to many as the back g... Despite hardship and suffering,many quake survivors remain generous and optimistic Liu Jing’s hometown,Xiangxi Village in Anxian County,Sichuan Province,was a picturesque place, in an area known to many as the back garden of the industrial city Mianyang, until May 12. Since then it has become better 展开更多
关键词 picking up the Pieces
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Real Estate Industry Picking Up
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《China City Planning Review》 1992年第3期28-28,共1页
The real estate industry in China ispicking up rapidly after a couple of years’economic adjustment.According to thenewest statistics, indices like constructionarea by housing development companies,area of commerciali... The real estate industry in China ispicking up rapidly after a couple of years’economic adjustment.According to thenewest statistics, indices like constructionarea by housing development companies,area of commercialized housing soldout, floor area of commercialized residentialbuilding sold out,aggregate sales of com-mercialized housing,as well as the percen- 展开更多
关键词 Real Estate Industry picking up
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Pregnancy outcomes following supplementation of single dose GnRH agonist to sustain the luteal phase in antagonist fresh embryo transfer cycles:A multicentric prospective cohort study
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作者 Tatapudi S V Parvathi Devi Alka Gahlot +3 位作者 Sangita Sharma Manisha Choudhary Ravikant Soni Meeta Sharma 《Asian pacific Journal of Reproduction》 2023年第4期162-169,共8页
Objective:To determine whether a single dose of gonadotropin-releasing hormone(GnRH)agonist administered subcutaneously in addition to the regular progesterone supplementation could provide a better luteal support in ... Objective:To determine whether a single dose of gonadotropin-releasing hormone(GnRH)agonist administered subcutaneously in addition to the regular progesterone supplementation could provide a better luteal support in antagonist protocol fresh embryo transfer cycles.Methods:This prospective,multicentric,cohort study included total 140 women,70 in each group.Controlled ovarian stimulation was carried out as per fixed GnRH antagonist protocol.The trigger was given with hCG.In vitro fertilization/intracytoplasmic sperm injection(IVF/ICSI)was performed and day-3 embryos were transferred.Patients were divided into groups 1 and 2 based on computer generated randomization sheet.Six days following oocyte retrieval,group 1 received 0.2 mg decapeptyl subcutaneously in addition to regular progesterone support while group 2 received progesterone only.Luteal support was given for 14 days to both groups;if pregnancy was confirmed luteal support was continued till 12 weeks of gestation.The clinical pregnancy rate was the primary outcome.The implantation rate,miscarriage rate,live birth delivery rate,and multiple pregnancy rates were the secondary outcomes.Results:A total of 140 patients were analysed,70 in each group.Clinical pregnancy rates(47.1%vs.35.7%;P=0.17),implantation rates(23.4%vs.18.1%,P=0.24),live birth delivery rates(41.4%vs.27.1%,P=0.08),and multiple pregnancy rates(21.2%vs.16.0%,P=0.74)were higher in group 1 than in group 2.Group 1 had a lower miscarriage rate than group 2(5.7%vs.8.6%;P=0.75).However,these differences were not statistically significant between the two groups.Conclusions:Administration of a single dose of GnRH agonist in addition to regular natural micronized vaginal progesterone as luteal support in GnRH antagonist protocol cycles marginally improves implantation rates,clinical pregnancy rates,and live birth delivery rates.However,more studies with higher sample sizes are needed before any conclusive statements about GnRH agonist as luteal phase support can be made. 展开更多
关键词 GnRH agonist TRIPTORELIN IVF Ovum pick up Luteal phase support Antagonist protocol Cleavage stage Fresh embryo transfer Live birth delivery rate
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Landscape Design of Sightseeing and Picking Garden Transformed from Vegetable Producing Garden 被引量:1
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作者 孙明德 曹均 《Journal of Landscape Research》 2011年第5期4-7,共4页
In view of landscape design problems in the transition from vegetable producing garden to sightseeing and picking garden,definitions of both gardens were introduced and discriminated.It was proposed that landscapes in... In view of landscape design problems in the transition from vegetable producing garden to sightseeing and picking garden,definitions of both gardens were introduced and discriminated.It was proposed that landscapes in the vegetable sightseeing and picking garden included installations,open-field vegetable producing landscapes and overall environment landscapes.Landscape design concepts and principles of vegetable sightseeing and picking garden were analyzed,and it was stressed that its landscape design should take quality production of vegetables and fruits as the principal line,environment landscapes of the garden as the support,and experiencing production process as the feature,by following the principles of "integrity of garden design,characteristic vegetable varieties,proper crop rotation,ecological production process".Landscape contents of this garden were analyzed from 3 perspectives:landscape design within installations,major road,and overall appearance of the garden.Cangshang Vegetable Sightseeing and Picking Garden in Beiwu Township,Shunyi District,Beijing City was taken for an example to analyze its landscape construction inside and outside greenhouses as well as the optimization of the overall environment landscapes on the basis of introducing its landscape design concepts. 展开更多
关键词 VEGETABLE GARDEN SIGHTSEEING and picking LANDSCAPE DESIGN
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CREDIT-X1local:A reference dataset for machine learning seismology from ChinArray in Southwest China
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作者 Lu Li Weitao Wang +1 位作者 Ziye Yu Yini Chen 《Earthquake Science》 2024年第2期139-157,共19页
High-quality datasets are critical for the development of advanced machine-learning algorithms in seismology.Here,we present an earthquake dataset based on the ChinArray Phase I records(X1).ChinArray Phase I was deplo... High-quality datasets are critical for the development of advanced machine-learning algorithms in seismology.Here,we present an earthquake dataset based on the ChinArray Phase I records(X1).ChinArray Phase I was deployed in the southern north-south seismic zone(20°N-32°N,95°E-110°E)in 2011-2013 using 355 portable broadband seismic stations.CREDIT-X1local,the first release of the ChinArray Reference Earthquake Dataset for Innovative Techniques(CREDIT),includes comprehensive information for the 105,455 local events that occurred in the southern north-south seismic zone during array observation,incorporating them into a single HDF5 file.Original 100-Hz sampled three-component waveforms are organized by event for stations within epicenter distances of 1,000 km,and records of≥200 s are included for each waveform.Two types of phase labels are provided.The first includes manually picked labels for 5,999 events with magnitudes≥2.0,providing 66,507 Pg,42,310 Sg,12,823 Pn,and 546 Sn phases.The second contains automatically labeled phases for 105,442 events with magnitudes of−1.6 to 7.6.These phases were picked using a recurrent neural network phase picker and screened using the corresponding travel time curves,resulting in 1,179,808 Pg,884,281 Sg,176,089 Pn,and 22,986 Sn phases.Additionally,first-motion polarities are included for 31,273 Pg phases.The event and station locations are provided,so that deep learning networks for both conventional phase picking and phase association can be trained and validated.The CREDIT-X1local dataset is the first million-scale dataset constructed from a dense seismic array,which is designed to support various multi-station deep-learning methods,high-precision focal mechanism inversion,and seismic tomography studies.Additionally,owing to the high seismicity in the southern north-south seismic zone in China,this dataset has great potential for future scientific discoveries. 展开更多
关键词 earthquake dataset machine learning Pg/Sg/Pn/Sn phase picking P-wave first-motion polarity
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含义丰富的Pick up
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作者 刘奉越 《中学文科(初中生学习与考试)》 2004年第4期32-32,共1页
在我们的课本中,有这么一个句子:Have you ever picked up a library book?在这里pick up意为“捡到”。在不同的语言环境里,pick up可表示不同的含义,本文就其用法和含义作一归纳。
关键词 “pick up 用法 词组 初中 英语
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Study on the Optimum Picking Time of Callicarpa kwangtungensis 被引量:1
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作者 孙刚 晏晨 +3 位作者 陈维 马四补 李春植 李开斌 《Agricultural Science & Technology》 CAS 2016年第9期2171-2173,2182,共4页
[Objective] This study was conducted to compare total contents of poliumoside and forsythoside B from Callicarpa kwangtungensis Chun in Qiandongnan Miao and Dong Autonomous Prefecture collected in different seasons, w... [Objective] This study was conducted to compare total contents of poliumoside and forsythoside B from Callicarpa kwangtungensis Chun in Qiandongnan Miao and Dong Autonomous Prefecture collected in different seasons, which could provide reference for its deep development and utilization. [Methods] Poliumoside and forsythoside B were measured according to the pharmacopoeia standard in the middle of each month in 2014, and the yield of C. kwangtungensis was simultaneously evaluated. All these results provided data reference for the determination of suitable picking time for C. kwangtungensis. [Results] The results showed the content of poliumoside and forsythoside B in C. kwangtungensis was the highest in November, and the content of the medicinal material in August was over eight times higher than the pharmacopoeia standard, besides at this month the yield was the highest during the year. Comprehensively, mid October is the optimum picking time for C. kwangtungensis in Taijiang. [Conclusion] Dynamic variations of content of poliumoside and forsythoside B in and yield of C. kwangtungensis were investigated, which would significantly benefit production of C. kwangtungensis in Qiandongnan Miao and Dong Autonomous Prefecture. 展开更多
关键词 Poliumoside Forsythoside B picking time
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你了解pick up的用法吗?
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作者 盘笋 《疯狂英语(初中天地)》 2002年第48期9-9,共1页
“pick up”在中学英语课本中出现早,使用频率高,而且它在不同的语言环境中的含义和用法存在着很大的差异。为帮助同学们比较全面地了解和使用这一短语,本文拟将它的基本含义和用法作一归纳,供读者朋友们参考。1.表示“拾起、捡起、拿... “pick up”在中学英语课本中出现早,使用频率高,而且它在不同的语言环境中的含义和用法存在着很大的差异。为帮助同学们比较全面地了解和使用这一短语,本文拟将它的基本含义和用法作一归纳,供读者朋友们参考。1.表示“拾起、捡起、拿起”的意思。如: The boy picked up a watch in the street andhanded it to the police. 那男孩在街上拾到一块手表,把它交给了警察。He picked up the telephone and talked to afriend over it for a long time. 展开更多
关键词 pick up
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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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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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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 statist!cs, is proposed for processing noisy data from underground mines. The objectives of this method are to (1) Improve manual detection and tPicking of P-phase onset; and (ii) provide an automatic means of detecting and picking P-phase onset me 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 me!hod 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 Manual P-phase detection Automatic onset picking Noisy microseismic data Kurtosis Skewness
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SegNet-based first-break picking via seismic waveform classification directly from shot gathers with sparsely distributed traces 被引量:3
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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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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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