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Bridging element-free Galerkin and pluri-Gaussian simulation for geological uncertainty estimation in an ensemble smoother data assimilation framework

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Petroleum Science 2024年第3期21卷 1683-1698页

作者： bogdan Sebacher Remus Hanea Department of Applied informatics Military Technical Academy “Ferdinand I” Equinor

The facies distribution of a reservoir is one of the biggest concerns for geologists, geophysicists, reservoir modelers, and reservoir engineers due to its high importance in the setting of any reliable decisionmaking/optimization of field development planning. The approach for parameterizing the facies distribution as a random variable comes naturally through using the probability fields. Since the prior probability fields of facies come either from a seismic inversion or from other sources of geologic information, they are not conditioned to the data observed from the cores extracted from the wells. This paper presents a regularized element-free Galerkin(R-EFG) method for conditioning facies probability fields to facies observation. The conditioned probability fields respect all the conditions of the probability theory(i.e. all the values are between 0 and 1, and the sum of all fields is a uniform field of 1). This property achieves by an optimization procedure under equality and inequality constraints with the gradient projection method. The conditioned probability fields are further used as the input in the adaptive pluri-Gaussian simulation(APS) methodology and coupled with the ensemble smoother with multiple data assimilation(ES-MDA) for estimation and uncertainty quantification of the facies distribution. The history-matching of the facies models shows a good estimation and uncertainty quantification of facies distribution, a good data match and prediction capabilities.

关键词： Element free Galerkin (EFG) Adaptive pluri-Gaussian simulation (APS) Facies distribution estimation Ensemble smoother with multiple data assimilation (ESMDA)

Competitive effect, but not competitive response, varies along a climatic gradient depending on tree species identity

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Forest Ecosystems 2024年第2期11卷 142-151页

作者： Teresa Valor Lluís Coll David i.Forrester Hans Pretzsch Miren del Río Kamil Bielak bogdan Brzeziecki Franz Binder Torben Hilmers Zuzana Sitková Roberto Tognetti Aitor Ameztegui Department of Agricultural and Forest Sciences and Engineering(DCEFA) University of LleidaAv.Alcalde Rovira Roure 191E25198 LleidaSpain Joint Research Unit CTFC-AGROTECNiO-CERCA Ctra.Sant LlorençKm.225280SolsonaSpain Swiss Federal institute of Forest Snow and Landscape Research WSLZürcherstrasse 1118903BirmensdorfSwitzerland CSiRO Land and Water GPO Box 1700CanberraACT2601Australia Chair of Forest Growth and Yield Science School of Life Sciences WeihenstephanTechnical University of MunichHans-Carl-Von-Carlowitz-Platz 285354FreisingGermany Forest Research Center INIA-CSICCtra.A Coruña Km 7.528040MadridSpain iuFOR Sustainable Forest Management Research InstituteUniversity of Valladolid&INIASpain Department of Silviculture Institute of Forest SciencesWarsaw University of Life SciencesNowoursynowska 159/3402776WarsawPoland Bavarian State institute of Forestry(LWF) Hans-Carl-von-Carlowitz-Platz 1D-85354FreisingGermany National Forest Centre Forest Research InstituteT.G.Masaryka 2296001ZvolenSlovakia Faculty of Agricultural Environmental and Food SciencesFree University of Bozen-Bolzano Piazza Università1 I-39100Bolzano

Background: Understanding the role of species identity in interactions among individuals is crucial for assessing the productivity and stability of mixed forests over time. However, there is limited knowledge concerning the variation in competitive effect and response of different species along climatic gradients. in this study, we investigated the importance of climate, tree size, and competition on the growth of three tree species: spruce(Picea abies), fir(Abies alba), and beech(Fagus sylvatica), and examined their competitive response and effect along a climatic gradient.Methods: We selected 39 plots distributed across the European mountains with records of the position and growth of 5,759 individuals. For each target species, models relating tree growth to tree size, climate and competition were proposed. Competition was modelled using a neighbourhood competition index that considered the effects of inter-and intraspecific competition on target trees. Competitive responses and effects were related to climate.Likelihood methods and information theory were used to select the best model.Results: Our findings revealed that competition had a greater impact on target species growth than tree size or climate. Climate did influence the competitive effects of neighbouring species, but it did not affect the target species? response to competition. The strength of competitive effects varied along the gradient, contingent on the identity of the interacting species. When the target species exhibited an intermediate competitive effect relative to neighbouring species, both higher inter-than intraspecific competitive effects and competition reduction occurred along the gradient. Notably, species competitive effects were most pronounced when the target species' growth was at its peak and weakest when growing conditions were far from their maximum.Conclusions: Climate modulates the effects of competition from neighbouring trees on the target tree and not the susceptibility of the target tree to competition. The modelling appr

关键词： Competition coefficient Competition reduction interspecific competition intraspecific competition Mixing effects Mixed species forest Neighbourhood models Plant-plant interactions

Comparison of stem volume estimates from terrestrial point clouds for mature Douglas-fir(Pseudotsuga menziessi(Mirb.)Franco)

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information Processing in Agriculture 2023年第3期10卷 334-346页

作者： Rong Fang bogdan M.Strimbu Forest Engineering Resourcesand Management DepartmentOregon State UniversityCorvallisOR 97333 ORUSA

As a complement to traditional estimates of stem dimensions from numerical models,terrestrial light detection and ranging(Lidar)provides direct stem diameter and volume values using cylindrical models constructed from point clouds.This study used two approaches to estimate total stem volume using Lidar and compared them with two empirical equations,one used by the Forest inventory Analysis in the Pacific Northwest(FiA-PNW)and one based on a taper equation.We fitted point clouds of 10 Douglas-fir with three sets of cylinder models that are distinguished by their segment length(i.e.0.5 m,1 m,and 2 m),then developed three taper equations based on the point-cloud-based diameter estimated previously.We estimated the total stem volume of the tree with eight models:six-point cloudbased(i.***.three taper and three cylinders)and two empirical.Finally,we used simulations to extrapolate the volume estimations of various methods for different diameters at breast height(DBH)classes.We found that all the point-cloud-based taper equations were similar in their performance(R2¼0:94,RMSE=4.6 cm)and produced mean volume estimates greater than mean estimates of the existing models.The cylinder models produced 11–16%greater mean volume estimates than the FiA-PNW estimate,with the 0.5 m segment length producing the greatest values,followed by the 1 m and 2 m segment length.The simulated data suggested that the mean volume estimates of a given DBH class are different when using different computation methods.ANOVA revealed a combined effect of the computation methods and the DBH class on the mean volume estimates.We conclude that the point-cloud-based taper equations,after being symmetrically calibrated,would be consistent with the regional stem volume estimates,whereas the cylinder models would be better in estimating individual stem volume.When constructing Lidar-based cylinder models in future applications,cylinder segment length would need to be adjusted to the length and DBH of the stem,as well as to the objectives of the research.

关键词： Lidar Cylinder models Cylinder segment length Taper equations Forest inventory and analysis

Production of Fibres from Lunar Soil:Feasibility,Applicability and Future Perspectives

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Advanced Fiber Materials 2022年第5期4卷 923-937页

作者： Ze‑Shi Guo Dan Xing Xiong‑Yu Xi Xiu Yue Cun‑Guang Liang Bin Hao Qingbin Zheng Sergey i.Gutnikov bogdan i.Lazoryak Peng‑Cheng Ma Laboratory of Environmental Science and Technology The Xinjiang Technical Institute of Physics and ChemistryKey Laboratory of Functional Materials and Devices for Special EnvironmentsChinese Academy of SciencesUrumqi 830011China Center of Materials Science and Optoelectronics Engineering University of Chinese Academy of SciencesBeijing 100049China School of Science and Engineering The Chinese University of Hong KongShenzhen 518172China Chemistry Department Lomonosov Moscow State University119991 MoscowRussia

The construction of a lunar base is considered to be an important step towards deep-space exploration by humanity,and will rely on the utilisation of in situ lunar resources.in this paper,we discuss the current knowledge on the feasibility of converting lunar soil to high-performance fibres that can be used for the construction of a lunar base.This fibre would be combined with further portions of lunar soil to generate fibre-reinforced composites,which is utilized as multi-functional materials for lunar base construction.We discuss and analyse the latest findings regarding the composition of lunar soil simulants and their fibrisation properties,and techniques for fibre spinning and system integration.Finally,we suggest how the achievements made so far could be applied to the construction of a lunar base.

关键词： Lunar soil Lunar fibre in-situ resource utilization Construction of lunar base

Pulmonary complications of portal hypertension:The overlooked decompensation

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World Journal of Clinical Cases 2022年第17期10卷 5531-5540页

作者： Rares Craciun Tudor Mocan bogdan Procopet Andrada Nemes Cristian Tefas Mihaela Sparchez Lavinia-Patricia Mocan Zeno Sparchez 3^(rd)Medical Clinic Department of Internal Medicine"Iuliu Hatieganu"University of Medicine and PharmacyCluj-Napoca 400162Romania Gastroenterology Clinic "Prof.Dr.O.Fodor"Regional Institute of Gastroenterology and HepatologyCluj-Napoca 400162Romania intensiv Care Unit i Cluj County Emergency HosptialCluj-Napoca 400006Romania 2^(nd)Paediatric Clinic "Iuliu Hatieganu"University of Medicine and PharmacyCluj-Napoca 400126Please enter the state or provinceRomania Department of Histology "Iuliu Hatieganu"University of Medicine and PharmacyCluj-Napoca 400349Romania

The systemic nature of cirrhosis and portal hypertension has long been recognized,and the amount of data characterizing the interplay between each system is becoming ever so complex.Lung involvement was among the first described associated entities in cirrhosis,with reports dating back to the late nineteenth century.However,it appears that throughout the years,interest in the pulmonary complications of portal hypertension has generally faded,especially in contrast to other decompensating events,as expertise in this field has primarily been concentrated in highly experienced tertiary care facilities and liver transplantation centers.Despite affecting up to 10%-15%of patients with advanced liver disease and having a proven prognostic impact,hepato-pulmonary syndrome,porto-pulmonary hypertension,and hepatic hydrothorax are frequently misdiagnosed,mistreated,or misinterpreted.This lack of precision might adversely impact patient care,referral to expert centers,and,ultimately,liver disease-related mortality and successful transplantation odds.The present minireview aims to increase awareness of the pulmonary complications of chronic liver disease by providing a brief overview of each of the three entities.The paper focuses on the essential theoretical aspects,addressing the most critical knowledge gaps on the one hand and,on the other hand,critically discussing one key issue for each complication.

关键词： Hepato-pulmonary syndrome Porto-pulmonary hypertension Hepatic hydrothorax Cirrhosis Portal hypertension Advanced liver disease

Geomechanical monitoring of rock's massive in zones of breaks

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中国有色金属学会会刊：英文版 2005年第S1期15卷 275-278页

作者： M. A. Zhuravkov S. i. bogdan M. A. Kovaleva Belarus State University Minsk 220050 BelarusBelarus State University Minsk 220050 BelarusBelarus State University Minsk 220050 Belarus

For safe development of underground space and especially in areas of geological infringements it is necessary to creat effective system of tracking, forecasting and management for deforming processes in such areas-system of geomechanical monitoring. Besides it is necessary to study and imagine the internal mechanism of deforming processes in such special zones. in the paper some basic aspects of creation of geomechanical monitoring systems for realization of supervision, study and modelling of deforming processes, for modelling and study of the stress-strain state of massif in areas of large-scale underground mining works in view of a block-hierarchical structure of rock’s massive (presence of geological infringements) are considered. in particular such important tasks, as research of deforming processes in areas of geological infringements with the help of GPS-technologies and use of the received results for the modeling; construction of models adequately describing a condition of rock’s massive in area of geological infringement. Some results of researches on study of cavities influence on occurrence of an area of limiting conditions in region of geological infringement and possible shift along infringement are submitted.

关键词： geological infringement shift displacement stress-strain state

Deep Learning-Based Model for Detection of Brinjal Weed in the Era of Precision Agriculture

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Computers, Materials & Continua 2023年第10期77卷 1281-1301页

作者： Jigna Patel Anand Ruparelia Sudeep Tanwar Fayez Alqahtani Amr Tolba Ravi Sharma Maria Simona Raboaca bogdan Constantin Neagu Department of Computer Science and Engineering Institute of TechnologyNirma UniversityAhmedabad382481India Software Engineering Department College of Computer and Information SciencesKing Saud UniversityRiyadh12372Saudi Arabia Computer Science Department Community CollegeKing Saud UniversityRiyadh11437Saudi Arabia Centre for inter-Disciplinary Research and innovation University of Petroleum and Energy StudiesDehradun248001India Doctoral School University Politehnica of BucharestBucharest060042Romania National Research and Development institute for Cryogenic and isotopic Technologies-iCSi Rm ValceaRamnicu Valcea240050Romania Power Engineering Department Gheorghe Asachi Technical University of IasiIasi700050Romania

The overgrowth of weeds growing along with the primary crop in the fields reduces crop production.Conventional solutions like hand weeding are labor-intensive,costly,and time-consuming;farmers have used herbicides.The application of herbicide is effective but causes environmental and health concerns.Hence,Precision Agriculture(PA)suggests the variable spraying of herbicides so that herbicide chemicals do not affect the primary plants.Motivated by the gap above,we proposed a Deep Learning(DL)based model for detecting Eggplant(Brinjal)weed in this paper.The key objective of this study is to detect plant and non-plant(weed)parts from crop images.With the help of object detection,the precise location of weeds from images can be achieved.The dataset is collected manually from a private farm in Gandhinagar,Gujarat,india.The combined approach of classification and object detection is applied in the proposed model.The Convolutional Neural Network(CNN)model is used to classify weed and non-weed images;further DL models are applied for object detection.We have compared DL models based on accuracy,memory usage,and intersection over Union(ioU).ResNet-18,YOLOv3,CenterNet,and Faster RCNN are used in the proposed *** outperforms all other models in terms of accuracy,i.e.,88%.Compared to other models,YOLOv3 is the least memory-intensive,utilizing 4.78 GB to evaluate the data.

关键词： Precision Agriculture Deep Learning brinjal weed detection ResNet-18 YOLOv3 CenterNet Faster RCNN

improvement of PCR reaction conditions for site-directed mutagenesis of big plasmids

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Journal of Zhejiang University-Science B(Biomedicine & Biotechnology) 2012年第4期13卷 244-247页

作者： bogdan MUNTEANU Mario BRAUN Kajohn BOONROD RLP AgroScience GmbH AlPlanta-Institute for Plant ResearchBreitenweg 71D-67435 NeustadtGermany

QuickChange mutagenesis is the method of choice for site-directed mutagenesis(SDM) of target se-quences in a plasmid.it can be applied successfully to small plasmids(up to 10 kb).However,this method cannot efficiently mutate bigger plasmids.Using KOD Hot Start polymerase in combination with high performance liquid chromatography(HPLC) purified primers,we were able to achieve SDM in big plasmids(up to 16 kb) involving not only a single base change but also multiple base changes.Moreover,only six polymerase chain reaction(PCR) cycles and 0.5 μl of polymerase(instead of 18 PCR cycles and 1.0 μl of enzyme in the standard protocol) were sufficient for the reaction.

关键词：指导地点的 mutagenesis (SDM ) 变异 Plasmid

Deep Feature Extraction and Feature Fusion for Bi-Temporal Satellite image Classification

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Computers, Materials & Continua 2021年第1期66卷 373-388页

作者： Anju Asokan bogdan Patrut Dana Danciulescu D.Jude Hemanth Department of ECE Karunya Institute of Technology and SciencesCoimbatoreIndia Department of Computer Science Alexandru Ioan Cuza University of la?ila?iRomania Department of Computer Science University of CraiovoCraiovoRomania

Multispectral images contain a large amount of spatial and spectral data which are effective in identifying change areas.Deep feature extraction is important for multispectral image classification and is evolving as an interesting research area in change detection.However,many deep learning framework based approaches do not consider both spatial and textural details into account.in order to handle this issue,a Convolutional Neural Network(CNN)based multi-feature extraction and fusion is introduced which considers both spatial and textural features.This method uses CNN to extract the spatio-spectral features from individual channels and fuse them with the textural features.Then the fused image is classified into change and unchanged regions.The presence of mixed pixels in the bitemporal satellite images affect the classification accuracy due to the misclassification errors.The proposed method was compared with six state-of-theart change detection methods and analyzed.The main highlight of this method is that by taking into account the spatio-spectral and textural information in the input channels,the mixed pixel problem is solved.Experiments indicate the effectiveness of this method and demonstrate that it possesses low misclassification errors,higher overall accuracy and kappa coefficient.

关键词： Remote sensing convolutional neural network deep learning multispectral bitemporal change detection