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| 1 | Three-dimensional experimental study of loose top-coal drawing law for longwall top-coal caving mining technology显示文摘Based on the loose medium flow field theory, the loose top-coal drawing law of longwall top-coal caving(LTCC) mining technology is studied by using self-developed three-dimensional(3D) test device. The loose top-coal drawing test with shields and the controlled test without shields are performed in the condition without any boundary effect. Test results show that shields will cause reduction in drawing volume of coal in the LTCC mining. The deflection phenomenon of drawing body is also observed in the controlled test, which is verified that the deflection of drawing body is caused by shield. It is found that the deflection angle decreases with increasing caving height, with the maximum value of atailand the minimum value of 0. In addition, the formula to calculate the drawing volume is proposed subsequently.The deflection of drawing body is numerically simulated using particle flow code PFC3 Dand the proposed formula to calculate drawing volume in LTCC is also verified. | Jiachen Wang Jinwang Zhang Zhengyang Song Zhaolong Li | 2015 | Journal of Rock Mechanics and Geotechnical Engineering2015，7，3： | 12 |
| 2 | Drawing mechanisms for top coal in longwall top coal caving(LTCC):A review of two decades of literature显示文摘This review details the state of the art in research on top coal drawing mechanisms in Longwall top coal caving(LTCC)by examining the relevant literature over the last two decades.It startswith an introduction of the brief history and basic procedures of LTCC.The framework of research on the drawing mechanism,basic concepts,and some theoretical models of LTCC are detailed in sect.research framework of top coal drawingmechanism.The authors note that theTop coal drawbody(TCD),Top coal boundary(TCB)and Top coal recovery ratio(TCRR)are key factors in the drawingmechanism.TheBody-boundary-ratio(BBR)research system has been the classic framework for research over the last 20 years.The modified Bergmark-Roos model,which considers the effects of the supporting rear canopy,flowing velocity of top coal,and its shape factor,is optimal for characterizing the TCD.A 3Dmodel to describe the TCB that considers the thicknesses of the coal seam and roof strata is reviewed.In sect.physical testing and numerical simulation,the physical tests and numerical simulations in the literature are classified for ease of bibliographical review,and classic conclusions regarding the drawing mechanism of top coal are presented and discussedwith elaborate illustrations and descriptions.The deflection of the TCDis noted,and is caused by the shape of the rear canopy.The inclined coal seam always induces a largerTCD,and a deflection in theTCDhas also been observed in it.The effects of the drawing sequence and drawing interval on the TCRR are reviewed,where a long drawing interval is found to lead to significant loss of top coal.Its flowing behavior and velocity distribution are also presented.Sect.practical applications of drawingmechanisms forLTCCmines 4 summarizes over 10 cases where the TCRRof LTCCmines improved due to the guidance of the drawing mechanism.The final section provides a summary of the work here and some open questions.Prospective investigations are highlighted to give researchers guidance on promising issues in future research on LTCC. | Jiachen Wang Shengli Yang Weijie Wei Jinwang Zhang Zhengyang Song | 2021 | International Journal of Coal Science & Technology2021，8，6： | 3 |
| 3 | Molecular cloning and expression patterns of the cholesterol side chain cleavage enzyme(CYP11A1) gene during the reproductive cycle in goose(Anas cygnoides)显示文摘Background: CYP11A1, a gene belonging to the family 11 of cytochrome P450, encodes a crucial steroidogenic enzyme that catalyzes the initial step in the production of all classes of steroids. Many studies show that CYP11A1 plays a role in ovary function. However, the role of CYP11A1 in goose reproductive cycle remains largely unknown.Results: In this study, full-length CYP11A1 c DNA of Zhedong goose was obtained using reverse transcription polymerase chain reaction(RT-PCR) and rapid amplification of c DNA ends(RACE). The c DNA consisted of a 96-base pair(bp) 5′untranslated region(UTR), a 179-bp 3′UTR and a 1509-bp open reading frame. The open reading frame encodes a putative 503 amino acid protein that shares high homology with CYP11A1 of other birds. The amino acid sequence possesses conserved domains of the P450 superfamily, which include the steroid-binding domain and the heme-binding region. Real-time quantitative polymerase chain reaction(q PCR) analysis revealed CYP11A1 mR NA was expressed ubiquitously in every Zhedong goose tissue analyzed, including the heart, liver, glandular stomach,lung, spleen, kidney, intestinum tenue, intestinum crassum, cerebrum, cerebellum, muscle, oviduct, pituitary,hypothalamus and ovary.. The relatively low levels of CYP11A1 m RNA were detected in pituitary, ovary and oviduct tissues at ovulation when compared with levels at oviposition. Interestingly, higher expression was observed in ovary and oviduct tissues during brooding. Lastly, higher m RNA expression of Yangzhou geese was detected during the ovulation period than that of Zhedong geese.Conclusions: Our findings reveal the sequence characterization and expression patterns of the CYP11A1 gene during the goose reproductive cycle, which may provides correlative evidence that CYP11A1 expression is important in reproduction activity. | Qi Xu Yadong Song Yang Chen Ran Liu Yang Zhang Yang Li Zhengyang Huang Wenming Zhao Guobin Chang Guohong Chen | 2016 | Journal of Animal Science and Biotechnology2016，7，2： | 2 |
| 4 | XiaoMu: an AI-driven assistant for MOOCs显示文摘Nowadays, massive open online courses(MOOCs), are attracting widespread interest as an alternative education model. Several MOOCs platforms, such as Coursera, edX,and Udacity have been built and they provide low-cost opportunities for anyone who needs to access a massive number of courses from the worldwide top universities. However, the learning completion rate of the learners via MOOCs is extremely low compared with that in real classroom learning.Thus, this study builds a system, called XiaoMu, to design intelligent intervention strategies for the learning process of learners and improve the learning efficiency through automatic analysis of courses and learners. We deployed our system on the website1), which is one of the largest MOOCs in China. | Zhengyang SONG Jie TANG Tracy Xiao LIU Wenjiang ZHENG Lili WU Wenzheng FENG Jing ZHANG | 2021 | Science China(Information Sciences)2021，64，6： | 1 |
| 5 | Added Value of Diffusion-weighted MR Imaging to T2-weighted and Dynamic Contrast-enhanced MR Imaging in T Staging of Gastric Cancer显示文摘 | Song Liu Jian He Wenxian Guan Qiang Li Haiping Yu Zhuping Zhou Shanhua Bao Zhengyang Zhou | 2013 | Clinical Imaging2013，，： | 1 |
| 6 | Resonance Suppression Strategy for Humanoid Robot Arm显示文摘To address the problem of resonance in the control of a robot arm,a resonance suppression strategy is proposed for a single-joint humanoid robot arm based on the proportionalresonant(PR)controller.First,an arm joint model of the humanoid robot is established.Then the influence of resonance frequency on the performance of the control system with the robot arm is analyzed.The voltage fluctuation of the drive motor caused by the changes in arm motion is recognized as the disturbance of the current loop.The PR controller has the characteristic of disturbance rejection at a specific frequency.The output fluctuation of the driving system caused by the change of arm motion state at the resonance frequency is suppressed.Therefore the output current of the inverter will not be affected by the vibration of the arm at the resonance frequency.Finally,the control system is verified by MATLAB/Simulink simulation.The simulation results demonstrate that the control strategy for the humanoid robot arm based on the PR controller can suppress the resonance of the arm effectively,improving the dynamic performance and system stability. | Weiling Zhang Qinjun Du Zhengyang Zhao Chuanming Song Wei Ding Yonggang Luo | 2020 | Journal of Beijing Institute of Technology2020，29，4： | 1 |
| 7 | A review of investigations on ground support requirements in coal burst‑prone mines显示文摘Ground support is widely implemented to mitigate dynamic rock failures in underground mines.This paper investigated the ground support requirements in burst-prone mines to mitigate the catastrophic dynamic rock failures of rock and/or coal bursts.First,the ground support principles and considerations in burst-prone conditions are identified.The objective of a ground support system is to increase the capacity to accommodate rock fracturing in a rockburst and,in turn,to minimize the kinetic energy of the ejected material.The support capacities of various yielding rockbolts and integrated support systems are then investigated using the test results in the laboratory.Apart from the energy absorption and yielding deformation capacity,the initial stiffness and energy absorption rate are also critical factors when applying yielding rockbolts in practice.Adding rope lacing and mesh strap to surface support elements can substantially enhance the support performance of the system.In practice,semi-analytical and empirical approaches are often used to determine the ground support elements in burst-prone areas.Semi-analytical methods first evaluate the support demand in burst risk zones and then select support elements according to their laboratory test results.Alternatively,empirical methods determine the ground support elements according to the locally established empirical rating scheme,which usually ranks the support capacities of various support systems based on ground support conditions and damage conditions.The outcomes of this study can provide insights into ground support strategies and assist the mining industry to develop effective coal burst control technologies. | Chunchen Wei Chengguo Zhang Ismet Canbulat Zhengyang Song Lianpeng Dai | 2022 | International Journal of Coal Science & Technology2022，9，1： | 1 |
| 8 | Numerical and theoretical investigations of the effect of the gangue-coal density ratio on the drawing mechanism in longwall top-coal caving显示文摘Discrete element calculations of the top-coal drawing process for diferent gangue-coal density ratios were conducted to investigate the efect of the gangue-coal density ratio on the drawing mechanism in longwall top-coal caving.The efects were analyzed for the drawing body,the top-coal boundary,and the recovery of top coal.The results show that for increasing density ratio,the initial drawing body on the goaf side is farther away from the drawing support and its width and volume gradually increase.The upper part of the sickle-shaped drawing body extends near the initial drawing body with increasing density ratio in the normal cycling stage,and the distance from the drawing body to the initial drawing body is its maximum width.The larger the density ratio,the smaller the height of the top coal above the goaf at the end of the initial drawing process.The height of the top-coal boundary decreases with increasing density ratio,until it reaches a limit.In a normal cycle,due to hysteretic development,the top-coal boundary moves toward the goaf until the density ratio is approximately 2.0,which is consistent with the physical experiment results.Finally,increasing the advance length of the working face is benefcial for increasing the overall recovery of top coal. | Jinwang Zhang Dongliang Cheng Yinchao Yang Weijie Wei Zhaolong Li Zhengyang Song | 2022 | International Journal of Coal Science & Technology2022，9，2： | 0 |
| 9 | Mechanical responses and acoustic emission behaviors of coal under compressive differential cyclic loading(DCL):a numerical study via 3D heterogeneous particle model显示文摘The stability of coal walls(pillars)can be seriously undermined by diverse in-situ dynamic disturbances.Based on a 3D par-ticle model,this work strives to numerically replicate the major mechanical responses and acoustic emission(AE)behaviors of coal samples under multi-stage compressive cyclic loading with different loading and unloading rates,which is termed differential cyclic loading(DCL).A Weibull-distribution-based model with heterogeneous bond strengths is constructed by both considering the stress-strain relations and AE parameters.Six previously loaded samples were respectively grouped to indicate two DCL regimes,the damage mechanisms for the two groups are explicitly characterized via the time-stress-dependent variation of bond size multiplier,and it is found the two regimes correlate with distinct damage patterns,which involves the competition between stiffness hardening and softening.The numerical b-value is calculated based on the mag-nitudes of AE energy,the results show that both stress level and bond radius multiplier can impact the numerical b-value.The proposed numerical model succeeds in replicating the stress-strain relations of lab data as well as the elastic-after effect in DCL tests.The effect of damping on energy dissipation and phase shift in numerical model is summarized. | Zhengyang Song Yunfeng Wu Yong Zhang Yi Yang Zhen Yang | 2023 | International Journal of Coal Science & Technology2023，10，3： | 0 |
| 10 | Metabolic profile differences in ACTH-dependent and ACTH-independent Cushing syndrome显示文摘Background:The most common etiologies of Cushing’’s syndrome(CS)are adrenocorticotropic hormone(ACTH)-producing pituitary adenoma(pitCS)and primary adrenal gland disease(adrCS),both of which burden patients with metabolic disturbance.The aim of this study was to compare the metabolic features of pitCS and adrCS patients.Methods:A retrospective review including 114 patients(64 adrCS and 50 pitCS)diagnosed with CS in 2009-2019 was performed.Metabolic factors were then compared between pitCS and adrCS groups.Results:Regarding sex,females suffered both adrCs(92.2%)and pitCS(88.0%)more frequently than males.Regarding age,patients with pitCS were diagnosed at a younger age(35.40±11.94 vs.39.65±11.37 years,p=0.056)than those with adrCS,although the difference was not statistically significant.Moreover,pitCS patients had much higher ACTH levels and more serious occurrences of hypercortisolemia at all time points(8 AM,4 PM,12 AM)than that in adrCS patients.Conversely,indexes,including body weight,BMI,blood pressure,serum total cholesterol,low density lipoprotein cholesterol(LDL-C),high density lipoprotein cholesterol(HDL-C),triglycerides,fasting plasma glucose,and uric acid,showed no differences between adrCS and pitCS patients.Furthermore,diabetes prevalence was higher in pitCS patients than in adrCS patients;however,there were no significant differences in hypertension or dyslipidemia prevalence between the two.Conclusions:Although adrCS and pitCS had different pathogenetic mechanisms,different severities of hypercortisolemia,and different diabetes prevalences,both etiologies had similar metabolic characteristics. | Zhengyang Li Chen Zhang Chong Geng Yongfeng Song | 2022 | Chronic Diseases and Translational Medicine2022，8，1： | 0 |
| 11 | Exogenous melatonin alleviated growth inhibition and oxidative stress induced by drought stress in apple rootstock显示文摘Drought stress is one of the major environmental obstacles that limit the production and development of apples(Malus domestica Borkh.).The role of melatonin is well known in the protection of plants under environmental stresses.In this study,we investigated the effect of melatonin on apple rootstock M.hupehensis Rehd under drought stress.The results showed that drought inhibited the growth of M.hupehensis and dramatically reduced root surface area,root volume,the number of tips and forks,and root diameter.Drought-induced growth inhibition was significantly decreased by adding melatonin.Net photosynthetic rate(Pn),intercellular CO_(2)concentration(Ci),stomatal conductance(Gs),transpiration rate(Tr),were markedly reduced under drought stress.However,the application of melatonin could mitigate the damage to the photosynthetic apparatus and increase the quantum yield of PSII photochemistry.Additionally,generation of hydrogen peroxide(H_(2)O_(2))and superoxide radicals(O_(2)^(•–))sharply increased in apple leaves after 4 days under drought stress,and the accumulation of electrolyte leakage(EL)represented oxidative stress,while by applying melatonin under drought stress,the generation of O_(2)^(•–)and H_(2)O_(2)were significantly reduced and protected the membrane from drought damages.These results suggest that the adverse effects of drought can be minimized by applying melatonin to apples. | MEIGE WANG JUAN GONG CHUNHUI SONG ZHENGYANG WANG SHANGWEI SONG JIAN JIAO MIAOMIAO WANG XIANBO ZHANG TUANHUI BAI | 2022 | BIOCELL2022，46，7： | 0 |
| 12 | LRRC25 plays a key role in all-trans retinoic acid-induced granulocytic differentiation as a novel potential leukocyte differentiation antigen显示文摘 | Weili Liu Ting Li Pingzhang Wang Wanchang Liu Fujun Liu Xiaoning Mo Zhengyang Liu Quansheng Song Ping Lv Guorui Ruan Wenling Han | 2018 | Protein & Cell2018，9，9： | 0 |
| 13 | Hybrid energy harvesting systems for self-powered sustainable water purification by harnessing ambient energy显示文摘The development of self-powered water purification technologies for decentralized applications is crucial for ensuring the provision of drinking water in resource-limited regions. The elimination of the dependence on external energy inputs and the attainment of self-powered status significantly expands the applicability of the treatment system in real-world scenarios. Hybrid energy harvesters, which convert multiple ambient energies simultaneously, show the potential to drive self-powered water purification facilities under fluctuating actual conditions. Here, we propose recent advancements in hybrid energy systems that simultaneously harvest various ambient energies (e.g., photo irradiation, flow kinetic, thermal, and vibration) to drive water purification processes. The mechanisms of various energy harvesters and point-of-use water purification treatments are first outlined. Then we summarize the hybrid energy harvesters that can drive water purification treatment. These hybrid energy harvesters are based on the mechanisms of mechanical and photovoltaic, mechanical and thermal, and thermal and photovoltaic effects. This review provides a comprehensive understanding of the potential for advancing beyond the current state-of-the-art of hybrid energy harvester-driven water treatment processes. Future endeavors should focus on improving catalyst efficiency and developing sustainable hybrid energy harvesters to drive self-powered treatments under unstable conditions (e.g., fluctuating temperatures and humidity). | Zhengyang Huo Young Jun Kim Yuying Chen Tianyang Song Yang Yang Qingbin Yuan Sang Woo Kim | 2023 | Frontiers of Environmental Science & Engineering2023，17，10： | 0 |
| 14 | Effect of heterogeneity on mechanical and micro-seismic behaviors of sandstone subjected to multi-level cyclic loading: A discrete element method investigation显示文摘In numerical simulation of the mechanical responses and acoustic emission(AE)characteristics of rocks under cyclic loading,the impacts of compositional heterogeneities of mineral grains have barely been considered.This will lead to a poor reproduction of rock’s behaviors in terms of stress-strain relationship and micro-seismic characteristics in numerical simulation.This work aims to analyze and reveal the impact of parameter heterogeneity on the rock’s fatigue and micro-seismic properties based on PFC3D.Two distribution patterns(uniform and Weibull distributions),are implemented to assign four critical parameters(i.e.tensile strength,cohesion,parallel bond stiffness and linear stiffness)for 32 sets of numerical schemes.The results show that the models with high heterogeneity of tensile strength and cohesion can better reproduce the stress-strain relationship as well as the patterns of cumulative AE counts and energy magnitude.The evolution of the proportion of three-level AE events in the laboratory test is consistent with the numerical results when the highly heterogeneous tensile strength and cohesion are distributed.The numerical results can provide practical guidance to the PFC-based modeling of rock heterogeneity when exposed to multi-level cyclic loading and AE monitoring. | Zhengyang Song Zhen Yang Min Zhang Fei Wang Martin Herbst Heinz Konietzky | 2023 | Journal of Rock Mechanics and Geotechnical Engineering2023，15，10： | 0 |
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