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Supply Coordination Based on Bonus Policy in Assembly under Uncertain Delivery Time

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Chinese Journal of Mechanical Engineering 2013年第2期26卷 293-303页

作者： LI Guo liu mengqi WANG Zhaohua PENG Bingzong School of Management and Economics Beijing Institute of technology School of Business Administration Hunan University School of Management Huazhong University of Science and Technology

The existing research of supply coordination under uncertain delivery time mainly focuses on the collaboration between the supplier and the manufacturer, which aim at minimizing the total cost of each side and finding comparative optimal solutions under decentralized decision. In the supply coordination, the collaboration between suppliers in assembly system is usually not considered. As a result, the manufacturer’s production is often delayed due to mismatching delivery of components between suppliers. Therefore, to ensure supply coordination in assembly system, collaboration between suppliers should be taken into consideration. In this paper, an assembly system with two suppliers and one manufacturer under uncertain delivery time is considered. The model is established and optimal solution is given under decentralized decision. Furthermore, the cost functions of two suppliers are both convex, and a unique Nash equilibrium exists between two suppliers. Then the optimal decision under supply coordination is analyzed, which is regarded as a benchmark for supply coordination. Additionally, the total cost of the assembly system is jointly convex in agreed delivery time. To achieve supply coordination a bonus policy is explored in the assembly system under uncertain delivery time, and the total cost under bonus policy must be lower than under decentralized decision. Finally the numerical and sensitivity analysis shows the cost of assembly system under bonus policy equals that under supply coordination, and the cost of each side in assembly system under bonus policy is lower compared to that under decentralized decision. The proposed research minimizes the total cost of each side with bonus policy in assembly system, ensures the supply coordination between suppliers and the manufacturer, and improves the competiveness of the whole supply chain.

关键词： supply coordination bonus policy assembly system uncertain delivery time

Use of lime mud from paper mill as a heterogeneous catalyst for transesterification

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Science China(Technological Sciences) 2014年第2期57卷 438-444页

作者： LI Hui NIU ShengLi LU ChunMei liu mengqi HUO MengJia School of Energy and Power Engineering National Engineering Laboratory for Coal-Burning Pollutants Emission Reduction Shandong University

Lime mud （LM）, a solid waste from the paper mill, is used as an economic and environmental friendly heterogeneous basic catalyst for transesterification, which is accompanied by characterization of X-ray fluorescence, thermogravimetric-differential thermal analysis, X-ray diffraction, N2 adsorption, and Hammett indicator method. To investigate the performance of the achieved catalyst, which is activated through calcination, the aspects of calcination temperature, reaction time, mole ratio of methanol to oil, catalyst addition percentage, and reaction temperature are concerned. Characterization of catalyst reveals that LM could be activated through calcination to transform the carbonate and hydrate of calcium into the oxide forms and higher calcination temperature could lead to stronger basic strength. However, N2 adsorption results indicate that higher temperature causes the sintering of the catalyst and shrinkage of the catalyst grains. When LM is activated at 800℃ （LM-800） and the reac- tion is carried out at 64℃ with a methanol to oiL mole ratio of 15：1, catalyst addition percentage of 6%, and reaction time of 2 h, the maximum transesterification conversion of 94.35% could be achieved. Reusability of LM-800 is also investigated com- pared with laboratory grade CaO in five reaction cycles and the results indicate that the catalysts derived from LM can be used as an economic and efficient catalyst for biodiesel production.

关键词： lime mud biodiesel heterogeneous catalyst transesterification industry waste

Numerical Study on the Gas Leakage and Dispersion at the Street Intersection of a Building Group

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Computer Modeling in Engineering & Sciences 2020年第6期123卷 1247-1266页

作者： Weitao Zhang mengqi liu Kaiyi Wang Fan Zhang Lei Hou National Engineering Laboratory for Pipeline Safety Beijing Key Laboratory of Urban Oil and Gas Distribution TechnologyChina University of PetroleumBeijing102249China CangHaiBang Business Unit Supply Chain Business GroupSinochem Energy High-Tech Co.Ltd.Beijing100094China Sinopec Economics&Development Research Institute Beijing100029China College of Arts and Science Boston UniversityBostonMA 02215USA.

Accidents involving natural gas leakage and dispersion pose a significant threat to human life and *** threat is especially relevant at the street intersection at which dense buildings,heavy traffic flow,and complex underground pipe networks *** have conducted numerous studies on gas leakage and dispersion,but investigations of natural gas leakage and dispersion at the street intersection of a building group are not *** this paper,we presented a three-dimensional(3D)physical model based on the Computational Fluid Dynamic(CFD)methodology to study the natural gas leakage and dispersion at the street intersection of a building *** validated the CFD methodology applied in the research based on the data from the field tests and wind tunnel ***,we simulated and analyzed the pressure,wind,and concentration of natural gas dispersion at the street *** simulation results showed that vortex regions,low-pressure zones,and a building group effect could cause a build-up of natural gas concentration under perpendicular wind direction *** addition,the area of hazardous region tended to increase first and then drop with the dispersion *** the case of this study,the maximum area of hazardous region is 200 m2 located in the height of 55 m,which is the middle plane in the computational *** results in the paper can provide scientific references for the safe operation and emergency-management decisions of municipal gas.

关键词： Natural gas computational fluid dynamic building group street intersection leakage and dispersion numerical simulation concentration field

Value-Added Products Derived from 15 Years of High-Quality Surface Solar Radiation Measurements at Xianghe,a Suburban Site in the North China Plain

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Advances in Atmospheric Sciences 2023年第6期40卷 1132-1141页

作者： mengqi liu Xuehua FAN Xiang'ao XIA Jinqiang ZHANG Jun LI Key Laboratory of Atmospheric Sounding Chengdu University of Information TechnologyChengdu 610225China LAGEO Institute of Atmospheric PhysicsChinese Academy of SciencesBeijing 100029China Collaborative Innovation Center on Forecast and Evaluation of Meteorological Disasters Nanjing University of Information Science&TechnologyNanjing 210044China College of Earth and Planetary Sciences University of Chinese Academy of SciencesBeijing 100049China

Surface solar radiation(SSR) is a key component of the energy budget of the Earth’s surface, and it varies at different spatial and temporal scales. Considerable knowledge of how and why SSR varies is crucial to a better understanding of climate change, which surely requires long-term measurements of high quality. The objective of this study is to introduce a value-added SSR dataset from Oct 2004 to Oct 2019 based on measurements taken at Xianghe, a suburban site in the North China Plain;two value-added products based on the 1-minute SSR measurements are developed. The first is clear sky detection by using a machine learning model. The second is cloud fraction estimation derived from an effective semiempirical method. A “brightening” of global horizontal irradiance(GHI) was revealed and found to occur under both clear and cloudy conditions. This could likely be attributed to a reduction in aerosol loading and cloud fraction. This dataset could not only improve our knowledge of the variability and trend of SSR in the North China Plain, but also be beneficial for solar energy assessment and forecasting.

关键词： surface solar radiation clear sky detection cloud fraction North China Plain

Enhanced thermal isolation in porous thermal barrier coatings by the formation of pore guided thermal-shock cracks

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Science China(Technological Sciences) 2023年第4期66卷 1007-1017页

作者： ZHEN Yu WU KaiJin liu mengqi ZHENG SongLin HE LingHui YU Yin NI Yong CAS Key Laboratory of Mechanical Behavior and Design of Materials Department of Modern MechanicsCAS Center for Excellence in Complex System MechanicsUniversity of Science and Technology of ChinaHefei 230026China National Key Laboratory of Shock Wave and Detonation Physics China Academy of Engineering PhysicsInstitute of Fluid PhysicsMianyang 621900China

Pore structure design is an effective strategy to tailor the thermal isolation capability of thermal barrier coatings(TBCs).Pursuing optimal porosity is crucial to balance the requirements of thermal isolation and mechanical reliability since the pore structure shields thermal heat transfer but increases mechanical *** this work,we investigate how thermal heat transfer couples with fracture propagation in porous TBCs by the using thermo-mechanical coupling phase field model for *** simulated results show that cracks induced by thermal shock favor deflection that is sometimes perpendicular to the direction of heat *** thermal conductivity degradation by the transverse cracks significantly impedes thermal heat transfer,leads to enhanced reduction of the effective thermal conductivity of TBCs,decreases the average thermal stress of the substrate,and thus decreases the risk of the crack penetrating into the *** numerical results demonstrate that the phase field method fully considering the thermo-mechanical interaction between cracks and pores can be a useful tool to improve the thermal isolation of porous TBCs under extreme thermal shock loadings through pore structure design.

关键词： phasefield TBCs porosity thermal shock cracks

Data-driven Estimation of Cloud Effects on Surface Irradiance at Xianghe,a Suburban Site on the North China Plain

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Advances in Atmospheric Sciences 2022年第12期39卷 2213-2223页

作者： mengqi liu Jinqiang ZHANG Hongrong SHI Disong FU Xiang'ao XIA Key Laboratory of Atmospheric Sounding Chengdu University of Information TechnologyChengdu 610225China Key Laboratory of Middle Atmosphere and Global Environment Observation Institute of Atmospheric PhysicsChinese Academy of SciencesBeijing 100029China Collaborative Innovation Center on Forecast and Evaluation of Meteorological Disasters Nanjing University of Information Science&TechnologyNanjing 210044China

Clouds are a dominant modulator of the energy *** cloud shortwave radiative effect at the surface(CRE)is closely related to the cloud macro-and micro-physical *** observation of surface irradiance and cloud properties are needed to narrow uncertainties in *** this study,1-min irradiance and Total Sky Imager measurements from 2005 to 2009 at Xianghe in North China Plain are used to estimate cloud types,evaluate cloud fraction(CF),and quantify the sensitivities of surface irradiance with respect to changes in CF whether clouds obscure the sun or *** annual mean CF is 0.50,further noting that CF exhibits a distinct seasonal variation,with a minimum in winter(0.37)and maximum in summer(0.68).Cumulus occurs more frequently in summer(32%),which is close to the sum of the occurrence of stratus and *** annual CRE is–54.4 W m^(–2),with seasonal values ranging from^(–2)9.5 W m^(–2)in winter and–78.2 W m^(–2)in *** clouds do not obscure the sun,CF is a dominant factor affecting diffuse irradiance,which in turn affects global *** is a positive linear relationship between CF and CRE under sun-unobscured conditions,the mean sensitivity of CRE for each CF 0.1 increase is about 1.2 W m^(–2)[79.5°

关键词： cloud radiative effect solar radiation cloud fraction cloud-radiation interaction

Role of CYP311A1 in wing development of Drosophila melanogaster

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Insect Science 2024年第3期31卷 748-758页

作者： Xubo Zhang mengqi liu Andi Cheng Bernard Moussian Jianzhen Zhang Wei Dong Shanxi Key Laboratory of Nucleic Acid Biopesticides Institute of Applied BiologyShanxi UniversityTaiyuanChina College of Life Science Shanxi UniversityTaiyuanChina INRAE CNRSInstitut Sophia AgrobiotechSophia AntipolisUniversite Cote d'AzurNiceFrance

Lipid homeostasis is crucial for growth and development of *** cytochrome P450 monooxygenases(CYPs)are involved in lipid *** function of Cyp3llal in the anterior midgut as a regulator of phosphatidylethanolamine(PE)metabolism in Drosophila melanogaster has been demonstrated,as depletion of Cyp31lal caused larval growth arrest that was partially rescued by supplying *** this study,we investigated the role of CYP311A1 in wing morphogenesis in *** the GAL4-UAS system,Cyp31lal was selectively knocked down in the wing disc.A deformed wing phenotype was observed in flies with reduced Cyp31lal *** and oil red O staining revealed a reduction of neutral lipids in the wing disc after the depletion of *** addition,we observed an enhanced sensitivity to Eosin Y penetration in the wings of Cyp31lal knocked-down ***,the reduction of CYP311A1 function in developing wings does not affect cell proliferation and apoptosis,but entails disordered Phalloidin or Cadherin distribution,suggesting an abnormal cell morphology and cell cortex structure in wing epithelial *** together,our results suggest that Cyp3llal is needed for wing morphogenesis by participating in lipid assembly and cell homeostasis.

关键词： apoptosis cell cortex cell proliferation Cyp31lal lipid wing

Arbitrarily polarized bound states in the continuum with twisted photonic crystal slabs

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Light(Science & Applications) 2023年第4期12卷 542-550页

作者： Haoye Qin Zengping Su mengqi liu Yixuan Zeng Man-Chung Tang Mengyao Li Yuzhi Shi Wei Huang Cheng-Wei Qiu Qinghua Song Tsinghua Shenzhen International Graduate School Tsinghua UniversityShenzhen 518055China Department of Electrical and Computer Engineering National University of SingaporeSingapore 117583Singapore Institute of Precision Optical Engineering School of Physics Science and EngineeringTongji UniversityShanghai 200092China Key Laboratory of Multifunctional Nanomaterials and Smart Systems Suzhou institute of Nano-Tech and Nano-Bionics(SINANO)Chinese Academy of Sciences(CAS)Suzhou 215123China

Arbitrary polarized vortex beam induced by polarization singularity offers a new platform for both classical optics and quantum entanglement *** states in the continuum(BICs)have been demonstrated to be associated with topological charge and vortex polarization singularities in momentum *** conventional symmetric photonic crystal slabs(PhCSs),BIC is enclosed by linearly polarized far fields with winding angle of 2π,which is unfavorable for high-capacity and multi-functionality integration-optics ***,we show that by breakingσz-symmetry of the PhCS,asymmetry in upward and downward directions and arbitrarily polarized BIC can be realized with a bilayer-twisted *** exhibits elliptical polarization states with constant ellipticity angle at every point in momentum space within the vicinity of *** topological nature of BIC reflects on the orientation angle of polarization state,with a topological charge of 1 for any value of ellipticity *** coverage of Poincarésphere(i.e.,-π/4≤X≤4 and-π/2≤ψ≤π/2)and higher-order Poincarésphere can be realized by tailoring the twist *** findings may open up new avenues for applications in structured light,quantum optics,and twistronics for photons.

关键词： Poincaré polarized twisted

Fengyun-4 Geostationary Satellite-Based Solar Energy Nowcasting System and Its Application in North China

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Advances in Atmospheric Sciences 2022年第8期39卷 1316-1328页

作者： Chunlin HUANG Hongrong SHI Ling GAO mengqi liu Qixiang CHEN Disong FU Shu WANG Yuan YUAN Xiang′ao XIA Key Laboratory of Aerospace Thermophysics Ministry of Industry and Information TechnologyHarbin Institute of TechnologyHarbin 150001China Key Laboratory of Middle Atmosphere and Global Environment Observation Institute of Atmospheric PhysicsChinese Academy of SciencesBeijing 100029China Collaborative Innovation Center on Forecast and Evaluation of Meteorological Disasters Nanjing University of Information Science&TechnologyNanjing 210044China National Satellite Meteorological Center China Meteorological AdministrationBeijing 100192China Key Laboratory of Atmospheric Sounding Chengdu University of Information TechnologyChengdu 610225China State Key Laboratory of Operation and Control of Renewable Energy&Storage Systems China Electric Power Research Institute(CEPRI)Beijing 100192China Key Laboratory of Cloud-Precipitation Physics and Severe Storms Institute of Atmospheric PhysicsChinese Academy of SciencesBeijing 100029China

Surface solar irradiance(SSI)nowcasting(0-3 h)is an effective way to overcome the intermittency of solar energy and to ensure the safe operation of grid-connected solar power *** this study,an SSI estimate and nowcasting system was established using the near-infrared channel of Fengyun-4A(FY-4A)geostationary *** system is composed of two key components:The first is a hybrid SSI estimation method combining a physical clear-sky model and an empirical cloudy-sky *** second component is the SSI nowcasting model,the core of which is the derivation of the cloud motion vector(CMV)using the block-matching *** goal of simultaneous estimation and nowcasting of global horizontal irradiance(GHI)and direct normal irradiance(DNI)is *** system was evaluated under different sky conditions using SSI measurements at Xianghe,a radiation station in the North China *** results show that the accuracy of GHI estimation is higher than that of DNI estimation,with a normalized root-mean-square error(nRMSE)of 22.4%relative to 45.4%.The nRMSE of forecasting GHI and DNI at 30-180 min ahead varied within 25.1%-30.8%and 48.1%-53.4%,*** discrepancy of SSI estimation depends on cloud occurrence frequency and shows a seasonal pattern,being lower in spring-summer and higher in *** FY-4A has great potential in supporting SSI nowcasting,which promotes the development of photovoltaic energy and the reduction of carbon emissions in *** system can be improved further if calibration of the empirical method is improved.

关键词： Fengyun-4A surface solar irradiance estimates and forecasting cloud motion block-matching