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Techno-economic feasibility assessment of a diesel exhaust heat recovery system to preheat mine intake air in remote cold climate regions

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International Journal of Mining Science and Technology 2020年第4期30卷 517-523页

作者： Marco Antonio Rodrigues de brito Durjoy baidya Seyed Ali Ghoreishi-Madiseh Norman b.Keevil Institute of Mining Engineering The University of British ColumbiaVancouverBC V6T 1Z4Canada

Underground mines in Arctic and Subarctic regions require the preheating of mine intake air during *** cold fresh air of those remote areas can be as severe as40℃ and commonly needs to be heated to around+3℃.This extensive amount of heating is usually provided by employing large-size air heaters,fueled by diesel,propane,natural gas,or heavy oil,leading to high energy costs and large carbon *** the same time,the thermal energy content of a diesel generator sets(gen-sets)exhaust is known to be one-third of the total heating value of its combusted *** heat recovery from diesel gen-sets is a growing technology that seeks to mitigate the energy costs by capturing and redirecting this commonly rejected exhaust heat to other applications such as space heating or pre-heating of the mine intake *** present study investigated the possibility of employing a simple system based on off-theshelf heat exchanger technology,which can recover the waste heat from the exhaust of the power generation units(diesel gen-sets)in an off-grid,cold,remote mine in Canada for heating of the mine intake *** from a real mine was used for the analysis along with environmental data of three different location-scenarios with distinct *** developing a thermodynamic model,the heat savings were calculated,and an economic feasibility evaluation was *** proposed system was found highly viable with annual savings of up to C$6.7 million and capable enough to provide an average of around 75%of the heating demand for mine intake air,leading to a payback period of about eleven months or less for all *** of seasonal thermal energy storage has also been recommended to mitigate the mismatch between supply and demand,mainly in summertime,possibly allowing the system to eliminate fuel costs for intake air heating.

关键词： Exhaust heat recovery Mine energy management Mine heating Alternative energy Intake air heating

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Molecular and Physiological Analysis of Growth-Limiting Drought Stress in brachypodium distachyon Leaves

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Molecular Plant 2013年第2期6卷 311-322页

作者： Wim verelst Edoardo bertolini Stefanie De bodt Klaas vandepoele Marlies Demeulenaere Mario Enrico pè Dirk Inzé Department of Plant Systems biology vie Technologiepark 927 9052 Gent Belgium Department of Plant biotechnology and bioinformatics Ghent University Technologiepark 927 9052 Gent Belgium Present address: Rijk Zwaan Zaadteelt en Zaadhandel b.v. Eerste Kruisweg 9 4793 RS Fijnaart The Netherlands Scuola Superiore Sant'Anna Piazza Martiri della Liberta 33 56127 Pisa Italy

The drought-tolerant grass brachypodium distachyon is an emerging model species for temperate grasses and cereal crops. To explore the usefulness of this species for drought studies, a reproducible in vivo drought assay was developed. Spontaneous soil drying led to a 45% reduction in leaf size, and this was mostly due to a decrease in cell expansion, whereas cell division remained largely unaffected by drought. To investigate the molecular basis of the observed leaf growth reduction, the third brachypodium leaf was dissected in three zones, namely proliferation, expan- sion, and mature zones, and subjected to transcriptome analysis, based on a whole-genome tiling array. This approach allowed us to highlight that transcriptome profiles of different developmental leaf zones respond differently to drought. Several genes and functional processes involved in drought tolerance were identified. The transcriptome data suggest an increased energy availability in the proliferation zones, along with an up-regulation of sterol synthesis that may influ-ence membrane fluidity. This information may be used to improve the tolerance of temperate cereals to drought, which is undoubtedly one of the major environmental challenges faced by agriculture today and in the near future.

关键词： brachypodium drought stress plant growth leaf.

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Developing a multi-label tinyML machine learning model for an active and optimized greenhouse microclimate control from multivariate sensed data

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Artificial Intelligence in Agriculture 2022年第1期6卷 129-137页

作者： Ilham Ihoume Rachid Tadili Nora Arbaoui Mohamed benchrifa Ahmed Idrissi Mohamed Daoudi Solar Energy and Environment Laboratory Mohammed V University in RabatFaculty of SciencesB.P 1014RabatMorocco

In the uncertainties within which the worldwide food security lies nowadays,the agricultural industry is raising a crucial need for being equipped with the state-of-the-art technologies for a more efficient,climate-resilient and sustainable *** traditional production methods have to be revisited,and opportunities should be given for the innovative solutions henceforth brought by big data analytics,cloud computing and internet of things(IoT).In this context,we develop an optimized tinyML-oriented model for an active machine learningbased greenhouse microclimate management to be integrated in an on-field *** design an experimental strawberry greenhouse from which we collect multivariate climate data through installed *** obtained values'combinations are labeled according to a five-action multi-label control strategy,then used to prepare a machine learning-ready *** dataset is used to train and five-fold cross-validate 90 Multi-Layer Perceptrons(MLPs)with varied hyperparameters to select the most performant–yet optimized–model instance for the addressed *** multi-label control approach enables designing highly scalable models with reduced computational complexity,comprising only n control neurons instead of(1+∑n k=1Cn k)neurons(usually generated from a classic single-label approach from n input variables).Our final selected model incorporates 2 hidden layers with 7 and 8 neurons respectively and 151 parameters;it scored a mean accuracy of 97%during the cross-validation phase,then 96%on our supplementary test *** model enables an intelligent and autonomous greenhouse management with the less required *** can be efficiently deployed in microcontrollers within real world operating conditions.

关键词： Agricultural greenhouse Microclimate control Machine learning Optimization TinyML

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Geomechanical analysis of an oil field:Numerical study of wellbore stability and reservoir subsidence

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Petroleum Research 2023年第3期8卷 350-359页

作者： Saeed Shad Parvin Kolahkaj Davood Zivar Department of Chemical and Petroleum Engineering Sharif University of TechnologyTehranIran PanTerra Geoconsultants b.v LeiderdorpNetherlands

Geomechanics as the knowledge of rock deformation and stability is an indispensable part of all field development *** geomechanical analyses leads to a safer and more efficient operation otherwise different kinds of instability and distortion might *** this study,the geomechanical behavior of Ilam and Sarvak formations of an oil field in southwest of Iran was *** research objectives can be summarized as wellbore stability evaluation and predicting the value of reservoir subsidence due to pressure drop as a result of reservoir fluid *** fulfill these,a set of petrophysical logs run in the exploration well of this green field were ***,using empirical correlations and statistical methods,required data for evaluating wellbore stability during drilling,specifying safe mud window to discover reservoir breakdown pressure,predicting the possibility of wellbore collapse in field lifetime,and assessing reservoir subsidence were *** results revealed that the average subsidence value as the consequence of production within 21 years is 0.275 ft Which is not *** terms of wellbore stability,it was concluded that all horizontal and vertical wells remain stable during this time *** to conclude,field development is not associated with alarming incidents from geomechanical aspect.

关键词： Dynamic geomechanical properties Subsidence Formation compaction Wellbore stability Stress streonet

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Evaluation of sample scale effect on geomechanical tests

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Petroleum Research 2022年第4期7卷 527-535页

作者： Maryam Kashfi Saeed Shad Davood Zivar Department of Chemical and Petroleum Engineering Sharif University of TechnologyTehranIran PanTerra Geoconsultants b.v LeiderdorpNetherlands

The size of the rock specimen affects the stress concentrates in the vicinity of the top/bottom of the rock specimen during the evaluation of the geomechanical parameters in the laboratory,which causes un-reliable ***,the appropriate size for geomechanical evaluation is not well understood yet because of limitations in the sampling and *** this study,a series of numerical simulations using a finite element package was conducted to investigate the effect of sample aspect ratio,fluid saturation,and porosity,on the mechanical behavior of the rock under elastic and poroelastic *** addition,two concepts,stress/strain homogeneity index(SHI)and representative elementary volume(REv),were developed to find out the appropriate sample *** results show that the presence of stiff platens,which are dissimilar to the specimen material,causes significant stress concentration in the two ends of the *** concentration of stress in the specimen reduces when the aspect ratio *** optimum aspect ratio(length-to-diameter equal to 3)was observed by SHI analysis which after that the changes in stress concentration are *** REv size analysis confirms the obtained optimum aspect ratio by SHI *** saturated specimens show a lower magnitude of stress than applied stress because of the presence of pore pressure,which can carry a portion of the *** higher void ratio results in lower strength of the *** study could be beneficial for the better design of geomechanical tests to have reliable results.

关键词： Geomechanics Stress concentration Stress/strain homogeneity index Representative elementary volume(REv) Poroelastic Scale dependency

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Genome-wide transcriptome analysis reveals molecular pathways involved in leafy head formation of Chinese cabbage(brassica rapa)

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Horticulture Research 2019年第1期6卷 95-107页

作者： XiaoXue Sun Ram Kumar basnet Zhichun Yan Johan bucher Chengcheng Cai Jianjun Zhao Guusje bonnema Key Laboratory of vegetable Germplasm Innovation and Utilization of Hebei Collaborative Innovation Center of Vegetable Industry in HebeiDepartment of HorticultureHebei Agricultural UniversityBaoding 071001China Plant breeding Wageningen University and ResearchWageningen 6708PBThe Netherlands Quantitative genetics department Rijk Zwaan Breeding B.V.Eerste Kruisweg 9Fijnaart 4793 RSThe Netherlands

Chinese cabbage plants go through seedling and rosette stages before forming their leafy *** cabbage plants resemble pak-choi plants at their seedling stage,but in their rosette stage the leaves of Chinese cabbage differentiate,as they increase in size with shorter *** order to understand the molecular pathways that play a role in leafy head formation,transcript abundance of young emerging leaves was profiled during development of two Chinese cabbage genotypes and a single pak-choi *** two Chinese cabbages differed in many aspects,among others earliness,leaf size and shape,leaf numbers,and leafy head ***-wide transcriptome analysis clearly separated the seedling stages of all three genotypes together with the later stages from pak-choi,from the later developmental stages of both Chinese cabbages(rosette,folding,and heading).Weighted correlation network analysis and hierarchical clustering using Euclidean distances resulted in gene clusters with transcript abundance patterns distinguishing the two Chinese cabbages from *** clusters included genes with transcript abundance affected by both genotype and developmental stage,whereas two clusters showed only genotype *** included a genotype by developmental stage cluster highly enriched with the MapMan category photosynthesis,with high expression during rosette and folding in Chinese cabbages and low expression in the heading inner leaves that are not exposed to *** other clusters contained many genes in the MapMan categories Cell,showing again differences between pak-choi and both Chinese *** discuss how this relates to the differences in leaf blade growth between Chinese cabbage and pak-choi,especially at the rosette ***,comparison of the transcriptome between leaves of two very different Chinese cabbages with pak-choi during plant development allowed the identification of specific gene categories associated with leafy head formation.

关键词： seedling heading analysis

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Weibull Statistics Strength Investigation of Synthetic Link Chains Made from Ultra-Strong Polyethylene Fibers

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Materials Sciences and Applications 2016年第5期7卷 238-246页

作者： Roel Marissen Dietrich Wienke René Homminga Rigo bosman Kjell Magne veka Anna Huguet DSM Dyneema b.v. Geleen Netherlands Load Solutions A/S R?dal/Bergen Norway Industrias Murtra S.A. Granollers/Barcelona Spain

Chains are typically used for tension load transfer. They are very flexible and allow easy length adjustment by hooking at the links. Steel is the traditional material for chains. Recently, synthetic link chains made from ultra-strong polyethylene fibers, branded as Dyneema®, are commercially available. These chains offer a highly improved strength to weight ratio. So far, one type of such chains is available, and it has a Working Load Limit of 100 kN. 50 of such chains, containing 6 links were tested to fracture. The strength of each chain and the location of the failed link were documented during testing for later interpretation. Weibull statistics was applied in order to extrapolate towards the allowable load for very low failure risks (high reliability). Two approaches were used. One extrapolation was based on all results;the other was applied after recognition that the end links failed under a slight negative influence by the connection to the testing equipment. Thus, in fact two populations are mixed, the chains with failing end links and the chains with failing central links. So considering the population without the failing end links is more representative for pure chain behavior without clamping effects. The results from this latter consideration showed a higher Weibull exponent, thus a more realistic extrapolation behavior. both methods indicate that the reliability at the working load limit of 100 kN is very good.

关键词： Fracture Stiching Fibers Reliability Dyneema® Minimum breaking Load Working Load Limit Extrapolation Populations Chain

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半自磨按比例放大及半自磨回路设计的计算机仿真技术

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有色冶金设计与研究 1998年第2期19卷 1-12页

作者： I.b.Klymowsky A.L.M.Rijkers 王莉萌 billiton Research b.v. Arnhem.Netherlands

本文叙述了直径为０．６９ｍ湿式半自磨机连续运转情况，并采用各种模型来预测按比例放大的半自磨机的性能特性。使用这种小型磨机一直是众多作者所争论的问题。然而由它所提供的试验数据的优点，已引起人们的关注，并按照这种试验思... 详细信息

本文叙述了直径为０．６９ｍ湿式半自磨机连续运转情况，并采用各种模型来预测按比例放大的半自磨机的性能特性。使用这种小型磨机一直是众多作者所争论的问题。然而由它所提供的试验数据的优点，已引起人们的关注，并按照这种试验思路继续研究。其优点是：所需的试料少；具有使用钻机获取岩芯来测试矿石易变性的能力；便于在不同操作条件下记录磨机内物料量的变化；容易倒空磨机内的物料。使用这种试验方法，每批试验仅需５００ｋｇ矿石。与大型半自磨机相比较，说明净比功耗的基本范围与产品粒度分布极为吻合。若用８０ｍｍ钢球和给矿粒度上限在８０～１２５ｍｍ范围内，必然会出现吻合的现象。大型半自磨机的所有特性，可由小型半自磨机模拟再现，并且容易测定，也可以比较用不同的模拟程序所做的预测。通过试验研究得出如下结论：只要知道钢球直径和试料的给矿粒度，则从小型自磨机的试验中获得的数据，可以准确用于半自磨回路的设计，即用常规公式，将计算结果直接按比例放大。模拟可以提高试验结果的价值，对许多选择性的试验非常有用。这种研究对以下２种情况更显示其优点：（１）可按比例放大建设因没有足够试料进行半工业试验的小选厂；（２）可按比例放大设计大型磨矿回路。

关键词：磨矿半自磨机计算机仿真磨矿机

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Selection Methodology of High-Cycle Fatigue Analysis Approach for Damage Estimation in Welded Structural Joints

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Journal of Marine Science and Application 2022年第4期21卷 116-133页

作者： Skirmantas Pargalgauskas Xiaoli Jiang Marcel Edelkamp Dingena Schott Department of Maritime and Transport Technology Delft University of TechnologyDelft 2628CDNetherlands In Summa Inovation b.v. Raamsdonksveer 4941VVNetherlands

The main purpose of this paper is to provide a summarized general guideline to aid decision making of choosing the type of fatigue analysis approach,best suited for modelling and evaluating high-cycle fatigue damage in welded structural *** describes how addition of stress concentration and stress direction information into fatigue assessment methodology affect simulated fatigue damage accumulation results and when it is beneficial or necessary to use a particular fatigue damage estimation *** focus is on stress-life curve based approaches,particularly when deciding between variants of nominal,hot-spot or multiaxial fatigue assessment approaches for evaluating fatigue damage within welded joint *** is illustrated through application of proposed methodology to choose and perform fatigue assessment for a non-conventional load-bearing tubular joint structure within a floating lemniscate crane upper arm,which has been observed of being prone to aggressive crack propagation within its *** within the structure is estimated using two non-optimal fatigue analysis approaches to verify applicability of proposed selection *** are then summarized through comparative assessment and findings are discussed based on what leads to result changes within each fatigue damage analysis approach.

关键词： Fatigue analysis Multiaxial fatigue Hot-spot fatigue Methodology Welded joints

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化学反应对流过半无限垂直多孔板的粘性耗散非定常磁流体流动的影响

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应用数学和力学 2011年第8期32卷 998-1010页

作者： J.A.饶 S.施崴阿赫奥斯曼尼阿大学数学系 b.v.拉朱技术学院数学系

分析了化学反应,对流过半无限竖直多孔板的、粘性耗散的、非定常的磁流体流动的影响.利用随时间变化的相似参数,将运动、能量、溶质的控制方程变换为常微分方程,并用有限单元法数值地求解所得到的常微分方程.用图形给出了不同参数对速... 详细信息

分析了化学反应,对流过半无限竖直多孔板的、粘性耗散的、非定常的磁流体流动的影响.利用随时间变化的相似参数,将运动、能量、溶质的控制方程变换为常微分方程,并用有限单元法数值地求解所得到的常微分方程.用图形给出了不同参数对速度、温度和浓度分布的影响,用表格给出了不同物理参数值时,表面摩擦力、Nusselt数和Sherwood数的数值.

关键词：磁流体动力学(MHD) 化学反应多孔介质粘性耗散有限元

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