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Soil Bulk Density Estimation Methods: A Review

Pedosphere 2018年第4期28卷 581-596页

作者： Ahmed Abed Gatea AL-SHAMMARY Abbas Z.KOUZANI Akif KAYNAK sui yang khoo Michael NORTON Will GATES School of Engineering Deakin University Soil Science and Water Resources Departments College of Agriculture University of Wasit Institute for Frontier Materials Deakin University

Measurement of soil bulk density is important for understanding the physical, chemical, and biological properties of soil. Accurate and rapid soil bulk density measurement techniques play a significant role in agricultural experimental research. This review is a comprehensive summary of existing measurement methods and evaluates their advantages, disadvantages, potential sources of error,and directions for future development. These techniques can be broadly categorised as direct and indirect methods. Direct methods include core, clod, and excavation sampling, whereas indirect methods include the radiation and regression approaches. The core method is most widely used, but it is time consuming and difficult to use for sampling multiple soil depths. The size of the coring cylinder used, operator experience, sampling depth, and in-situ soil moisture content significantly affect its accuracy. The clod method is suitable for use with heavy clay soils, and its accuracy is dependent on equipment calibration, drying time, and operator experience, but the process is complicated and time consuming. Excavation techniques are most commonly used to evaluate the bulk density of forest soils, but have major limitations as they cannot be used in soils with large pores and their measurement accuracy is strongly influenced by soil texture and the type of analysis selected. The indirect methods appear to have greater accuracy than direct approaches, but have higher costs, are more complex, and require greater operator experience. One such approach uses gamma radiation, and its accuracy is strongly influenced by soil depth. Regression methods are economical as they can make indirect measurements, but these depend on good, quality data of soil texture and organic matter content and geographical and climatic properties. Also, like most of the other approaches, its accuracy decreases with sampling depth.

关键词： measurement accuracy direct measurement methods gamma radiation indirect measurement methods regression methods sampling depth soil properties

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Power Quality Analysis in Microgrid: An Experimental Approach

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Journal of Power and Energy Engineering 2016年第4期4卷 17-34页

作者： Arangarajan Vinayagam KSV Swarna sui yang khoo Alex Stojcevski Faculty of Science Engineering and Built Environment Deakin University Geelong Australia Centre of Technology RMIT University Ho Chi Minh Vietnam

Microgrid (MG) integrated with Distributed Generation (DG) provides several benefits like reliable, secure, and high efficient of energy supply, while minimizing power loss, deferring expansion of power distribution infrastructures, and reduced carbon emission of energy supply etc. to the communities. Despite of the several benefits, there are several challenges existing due to the integration of different characteristics and technology of DG sources in MG network. Power Quality (PQ) issue is one of the main technical challenges in MG power system. In order to provide improved PQ of energy supply, it is necessary to analyse and quantify the PQ level in MG network. This paper investigates the detail of PQ impacts in a real MG network carried out through an experimental analysis. Voltage and frequency variations/deviations are analysed in both on-grid and off-grid mode of MG operation at varying generation and varying load conditions. Similarly unbalance voltage and current level in neutral are estimated at unbalanced PV generation and uneven load distribution in MG network. Also current and voltage THD are estimated at different PV power level. Finally the results obtained from the analysis are compared to that of Australian network standard level.

关键词： Microgrid Distributed Generation Power Quality Renewable Energy Total Harmonic Distortion

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Effects of the initiation position on the damage and fracture characteristics of linear-charge blasting in rock

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International Journal of Minerals,Metallurgy and Materials 2024年第3期31卷 443-451页

作者： Chenxi Ding Renshu yang Xiao Guo Zhe sui Chenglong Xiao Liyun yang School of Civil and Resource Engineering University of Science and Technology BeijingBeijing 100083China School of Mechanics and Civil Engineering China University of Mining and Technology(Beijing)Beijing 100083China School of Mathematics and Physics University of Science and Technology BeijingBeijing 100083China State Key Lab of Explosion Science and Technology Beijing Institute of TechnologyBeijing 100081China

To study the effects of the initiation position on the damage and fracture characteristics of linear-charge blasting, blasting model experiments were conducted in this study using computed tomography scanning and three-dimensional reconstruction methods. The fractal damage theory was used to quantify the crack distribution and damage degree of sandstone specimens after blasting. The results showed that regardless of an inverse or top initiation, due to compression deformation and sliding frictional resistance, the plugging medium of the borehole is effective. The energy of the explosive gas near the top of the borehole is consumed. This affects the effective crushing of rocks near the top of the borehole, where the extent of damage to Sections Ⅰ and Ⅱ is less than that of Sections Ⅲ and Ⅳ. In addition, the analysis revealed that under conditions of top initiation, the reflected tensile damage of the rock at the free face of the top of the borehole and the compression deformation of the plug and friction consume more blasting energy, resulting in lower blasting energy efficiency for top initiation. As a result, the overall damage degree of the specimens in the top-initiation group was significantly smaller than that in the inverse-initiation group. Under conditions of inverse initiation, the blasting energy efficiency is greater, causing the specimen to experience greater damage. Therefore, in the engineering practice of rock tunnel cut blasting, to utilize blasting energy effectively and enhance the effects of rock fragmentation, using the inverse-initiation method is recommended. In addition, in three-dimensional(3D) rock blasting, the bottom of the borehole has obvious end effects under the conditions of inverse initiation, and the crack distribution at the bottom of the borehole is trumpet-shaped. The occurrence of an end effect in the 3D linear-charge blasting model experiment is related to the initiation position and the blocking condition.

关键词： blasting linear charge initiation position computed tomography three-dimensional reconstruction damage

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PV Based Microgrid with Grid-Support Grid-Forming Inverter Control-(Simulation and Analysis)

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Smart Grid and Renewable Energy 2017年第1期8卷 1-30页

作者： Arangarajan Vinayagam K. S. V. Swarna sui yang khoo Aman Than Oo Alex Stojcevski Faculty of Science Engineering and Built Environment Deakin University Geelong Australia Centre of Technology RMIT University Ho Chi Minh City Vietnam

Microgrid (MG) is a small entity of electrical network which comprises of various Distributed Generation (DG) sources, storage devices, and group of loads in various classes. MG provides reliable and secure energy supply to the critical loads of communities while operating either in on-grid or off-grid mode. In this study, a coordinated power management control strategy for a typical low voltage (LV) MG network with integration of solar Photovoltaic (PV) and storage facility has been developed and analysed in Matlab-Simu-link software environment at various modes (on-grid, off-grid, and on-grid to off-grid transition) of MG operation. Solar PV and battery power inverters are considered as grid-support grid-forming (GsGfm) Voltage Source Inverter (VSI) with the implementation of modified droop and virtual output impedance control strategies. Proposed control strategy supports coordinated control operation between PV units and battery storage, equal power sharing among the DG sources, and smooth MG mode transition with regulation of voltage and frequency level in MG network. In addition, voltage and current THD level were analysed and verified as per the standard of AS4777.

关键词： Microgrid Distributed Generation Power Management Power Sharing Grid-Support Grid-Forming Inverter

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Reorientation and obstacle avoidance control of free-floating modular robots using sinusoidal oscillator

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Chinese Journal of Aeronautics 2024年第6期37卷 262-275页

作者： Zhiyuan yang Mingzhu LAI Jian QI Ning ZHAO Xin sui Jie ZHAO Yanhe ZHU State Key Laboratory of Robotics and System Harbin Institute of TechnologyHarbin 150001China School of Mathematics and Statistics Hainan Normal UniversityHaikou 571158China

This paper presents that a serpentine curve-based controller can solve locomotion control problems for articulated space robots with extensive flight phases,such as obstacle avoidance during free floating or attitude adjustment before *** proposed algorithm achieves articulated robots to use closed paths in the joint space to accomplish the above *** snakes,which can shuttle through gaps and adjust their landing posture by swinging their body during gliding in jungle environments,inspired the design of two *** first maneuver generates a rotation of the system by varying the moment of inertia between the joints of the robot,with the magnitude of the net rotation depending on the controller *** maneuver can be repeated to allow the robot to reach arbitrary *** second maneuver involves periodic undulations,allowing the robot to avoid collisions when the trajectory of the global Center of Mass(CM)passes through the *** maneuvers are based on the improved serpenoid curve,which can adapt to redundant systems consisting of different numbers of ***,the simulation illustrates that combining the two maneuvers can help a free-floating chain-type robot traverse complex *** proposed algorithm can be used with similar articulated robot models.

关键词： Collision avoidance Modularrobots Reorientation Free-floating space robots Nonholonomic systems Biologically inspired controllers Serpenoid curve

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Flow structure and shear stress in the presence of both ice cover on water surface and leafless vegetation in channel bed

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Journal of Hydrodynamics 2024年第2期36卷 340-354页

作者： Mahboubeh Barahimi Jueyi sui School of Engineering University of Northern British ColumbiaPrince GeorgeCanada

This study aimed to investigate the previously unexplored effects of ice cover and submerged vegetation on flow *** were undertaken under both open channel and ice-covered flow *** bed material consisted of three non-uniform *** findings revealed that when vegetation patches were present on the bed and an ice cover was present,the velocity profiles exhibited a distinctive pattern with two peak *** kinetic energy(TKE)also exhibited two peaks,one above the vegetation bending height and another at the sheath section,with a decreasing trend towards the ice ***,quadrant analysis showed that when the flow surface is covered by an ice cover,the contributions of inward and outward events increased compared with those observed in an open channel *** most cases,these contributions surpassed the sweep and ejection *** findings enhance our understanding of vegetation’s response to diverse surface conditions and have practical implications for river management and environmental engineering.

关键词： Ice cover vegetation flow structure Reynolds shear stress turbulent kinetic energy(TKE) quadrant analysis

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Establishment of genome-editing system and assembly of a near-complete genome in broomcorn millet

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Journal of Integrative Plant Biology 2024年第8期66卷 1688-1702页

作者： yang Liu Zixiang Cheng Weiyao Chen Chuanyin Wu Jinfeng Chen Yi sui State Key Laboratory of Integrated Management of Pest Insects and Rodents Institute of Zoologythe Chinese Academy of SciencesBeijing 100101China State Key Laboratory of Crop Gene Resources and Breeding Institute of Crop SciencesChinese Academy of Agricultural SciencesBeijing 100081China University of Chinese Academy of Sciences Beijing 100049China

The ancient crop broomcorn millet(Panicum miliaceum L.)is an indispensable orphan crop in semi-arid regions due to its short life cycle and excellent abiotic stress *** advantages make it an important alternative crop to increase food security and achieve the goal of zero hunger,particularly in light of the uncertainty of global climate ***,functional genomic and biotechnological research in broomcorn millet has been hampered due to a lack of genetic tools such as transformation and genome-editing ***,we successfully performed genome editing of broomcorn *** identified an elite variety,Hongmi,that produces embryogenic callus and has high shoot regeneration ability in in vitro *** established an Agrobacterium tumefaciens-mediated genetic transformation protocol and a clustered regularly interspaced short palindromic repeats(CRISPR)/Cas9-mediated genome-editing system for *** these techniques,we produced herbicide-resistant transgenic plants and edited phytoene desaturase(Pm PDS),which is involved in chlorophyll *** facilitate the rapid adoption of Hongmi as a model line for broomcorn millet research,we assembled a near-complete genome sequence of Hongmi and comprehensively annotated its ***,our results open the door to improving broomcorn millet using biotechnology.

关键词： broomcorn millet CRISPR/Cas9 editing genome assembly herbicide resistance transformation system

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Single-cell RNA sequencing analysis of the retina under acute high intraocular pressure

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Neural Regeneration Research 2024年第11期19卷 2522-2531页

作者： Shaojun Wang Siti Tong Xin Jin Na Li Pingxiu Dang yang sui Ying Liu Dajiang Wang Division of Ophthalmology The Third Medical Center of PLA General HospitalBeijingChina Department of Ophthalmology Beijing Rehabilitation HospitalCapital Medical UniversityBeijingChina

High intraocular pressure causes retinal ganglion cell injury in primary and secondary glaucoma diseases,yet the molecular landscape characteristics of retinal cells under high intraocular pressure remain *** models of acute hypertension ocular pressure were established by injection of cross-linked hyaluronic acid hydrogel(Healaflow■).Single-cell RNA sequencing was then used to describe the cellular composition and molecular profile of the retina following high intraocular *** results identified a total of 12 cell types,namely retinal pigment epithelial cells,rod-photoreceptor cells,bipolar cells,Müller cells,microglia,cone-photoreceptor cells,retinal ganglion cells,endothelial cells,retinal progenitor cells,oligodendrocytes,pericytes,and *** single-cell RNA sequencing analysis of the retina under acute high intraocular pressure revealed obvious changes in the proportions of various retinal cells,with ganglion cells decreased by 23%.Hematoxylin and eosin staining and TUNEL staining confirmed the damage to retinal ganglion cells under high intraocular *** extracted data from retinal ganglion cells and analyzed the retinal ganglion cell cluster with the most distinct *** found upregulation of the B3gat2 gene,which is associated with neuronal migration and adhesion,and downregulation of the Tsc22d gene,which participates in inhibition of *** study is the first to reveal molecular changes and intercellular interactions in the retina under high intraocular *** data contribute to understanding of the molecular mechanism of retinal injury induced by high intraocular pressure and will benefit the development of novel therapies.

关键词： apoptosis axon degeneration high intraocular pressure microglia ocular hypertension photoreceptor cells retina retinal degeneration retinal ganglion cells single-cell RNA sequencing

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Refractory autoimmune hemolytic anemia in a patient with systemic lupus erythematosus and ulcerative colitis:A case report

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World Journal of Clinical Cases 2024年第13期12卷 2286-2292页

作者： Dai-Xing Chen Yue Wu sui-Feng Zhang Xiao-Jun yang Department of Digestive System Chongqing Traditional Chinese Medicine HospitalChongqing 400021China

BACKGROUND Ulcerative colitis(UC)and systemic lupus erythematosus(SLE)are both systemic immunoreactive diseases,and their pathogenesis depends on the interaction between genes and environmental *** are no reports of UC with SLE in China,but six cases of SLE with UC have been reported in *** combination of these two diseases has distinct effects on the pathogenesis of both *** SUMMARY A female patient(30 years old)came to our hospital due to dull umbilical pain,diarrhea and mucous bloody stool in August 2018 and was diagnosed with *** symptoms were relieved after oral administration of mesalazine(1 g po tid)or folic acid(5 mg po qd),and the patient were fed a control *** June 24,2019,the patient was admitted for treatment due to anemia and *** hospitalization,the patient had repeated low-grade fever and a progressively decreased Hb *** tests revealed positive antinuclear antibody test,positive anti-dsDNA antibody,0.24 g/L C3(0.9-1.8 g/L),0.04 g/L C4(0.1-0.4 g/L),32.37 g/L immunoglobulin(8-17 g/L),and 31568.1 mg/24 h total 24-h urine protein(0-150 mg/24 h).The patient was diagnosed with SLE involving the joints,kidneys and blood *** reported cases of SLE were retrieved from PubMed to characterize clinicopathological features and identify prognostic factors for *** The patient was discharged in remission after a series of treatments,such as intravenous methylprednisolone sodium succinate,intravenous human immunoglobulin,cyclophosphamide injection,and plasma *** discharge,the patient took oral prednisone acetate tablets,cyclosporine capsules,hydroxychloroquine sulfate tablets and other treatments for symptoms and was followed up regularly for 1 month,after which the patient's condition continued to improve and stabilize.

关键词： Plasma exchange Autoimmune hemolytic anemia Systemic lupus erythematosus Ulcerative colitis Case report

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Self-Sustaining of Critical Park Microgrids Integrating Mobile Emergency Generators Subjective to Major Outage

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CSEE Journal of Power and Energy Systems 2024年第4期10卷 1441-1453页

作者： Quan sui Lei Zhang School of Electrical and Information Engineering Zhengzhou UniversityZhengzhou 450001China School of Electrical and New Energy Three Gorges UniversityYichang 443002China

In the event of a major power outage,critical park microgrids(PMGs)could be self-sustaining if mobile emergency generators(MEGs)are stationed to share ***,the need for privacy protection and the value of flexible power support on minute-time scales have not been given enough *** address the problem,this paper proposes a new self-sustaining strategy for critical PMGs integrating ***,to promote the cooperation between PMG and MEG,a bi-level benefit distribution mechanism is designed,where the participants'multiple roles and contributions are identified,and good behaviors are also ***,to increase the alliance benefits,three loss coordination modes are presented to guide the power exchange at the minute level between the MEG and PMG,considering the volatility of renewable generation and *** this basis,a multi-time scale power-energy scheduling strategy is formulated via the alternating direction method of multipliers(ADMM)to coordinate the PMG and ***,a dimensionality reduction technology is designed to equivalently simplify the optimization problem to facilitate the adaptive-step-based ADMM *** studies indicate that the proposed strategy achieves the self-sustaining of PMGs integrating MEGs while increasing the economy by no less than 3.1%.

关键词： Distributed optimization loss coordination mode mobile emergency generator park microgrid power-energy self-sustaining privacy protection

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