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Solid Rocket Booster Thrust Asynchrony Identification Method for Solid Rocket Bundled Rockets With ESO

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Aerospace China 2024年第1期25卷 40-46页

作者： WU Kao ZHANG Chi CHEN Yan XU Guoguang BU Xiangwei Oriental Space Technology(Shandong)Co. LtdBeijing 102600

The role of the rocket attitude control system is to execute the required maneuvers for guidance and ensure the stability of the rocket's flight attitude. Attitude control technology has always been one of the key technologies for ensuring the success of rocket flights and has been a core topic in carrier rocket technology research. The Gravity-1 solid carrier rocket is the first solid rocket bundled rocket developed by China, adopting a configuration with four boosters and a core stage bundled together. During the actual flight process, the four booster engines are ignited first, and then, in the event of insufficient control force from the boosters, the core stage engine is ignited to participate in control. To address thrust asynchrony during the descent of the four boosters, an Extended State Observer(ESO) is employed in the control scheme for this flight segment. This involves real-time estimation and compensation of attitude parameters during flight, identification of thrust asynchrony among the boosters, and simultaneous determination of whether the core stage engine is ignited to participate in *** six degrees of freedom simulation analysis and Y1 flight test validation, this method has been proven to be correct and feasible.

关键词： Extended State Observer(ESO) solid booster attitude control thrust asynchrony

High Precision Guidance System of the Gravity-1 Launch Vehicle

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Aerospace China 2024年第1期25卷 56-60页

作者： ZHANG Jie XU Guoguang BU Xiangwei Orienspace Technology(Shandong)Co. LtdBeijing 100076

In the development of the Gravity-1 launch vehicle, solid rocket motors without a thrust termination mechanism created great challenges for ascent guidance. To resolve this problem, the Gravity-1 GNC system used cross product guidance in the core 2nd stage, and a nonlinear adaptive guidance algorithm in core 3rd stage, in order to achieve high orbit injection precision. On January 11, 2024, the Gravity-1 launch vehicle successfully carried out its maiden flight from a mobile sea platform off the coast of Haiyang in Shandong province, inserting its payload into a low earth orbit at an altitude of 500 kilometers, validating the guidance algorithm.

关键词： Gravity-1 guidance system high precision

MEMS development focusing on collaboration using common facilities:a retrospective view and future directions

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Microsystems & Nanoengineering 2021年第4期7卷 25-33页

作者： Masayoshi Esashi MEMS core Co.ltd.(CTO) Sendai 981-3206Japan Micro System Integration Center(pSIC)(senior research fellow) Tohoku UniversitySendai 980-0845Japan

I have been developing MEMS(microelectromechanical systems)technology and supporting the industry through collaboration.A facility was built in house on a 20 mm square wafer for use in prototyping MEMS and ICs(integrated circuits).The constructed MEMS devices include commercialized integrated capacitive pressure sensors,electrostatically levitated rotational gyroscopes,and two-axis optical *** integration,which is a MEMS on an LSI(large-scale integration),was developed for sophisticated systems using LSI made in a *** technology was applied for tactile sensor networks for safe robots,multi FBAR filters on LSI,active-matrix multielectron emitter arrays,and so *** facility used to produce MEMS on 4-and 6-inch wafers was developed based on an old semiconductor factory and has been used as an open hands-on access facility by many *** directions of MEMS research are discussed.

关键词： scanner directions companies

Predicting Turbidite Channel in Deep-Water Canyon Based on Grey Relational Analysis-Support Vector Machine Model:A Case Study of the Lingshui Depression in Qiongdongnan Basin,South China Sea

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Energy Engineering 2024年第9期121卷 2435-2447页

作者： Haichen Li Jianghai Li Li Li Zhandong Li School of Earth and Space Sciences Peking UniversityBeijing100871China Key Laboratory of Orogenic Belts and Crustal Evolution Peking UniversityBeijing100871China Geotechnical Physical and Mechanical Properties Laboratory Langfang Normal UniversityLangfang065000China Heilongjiang Northeast Petroleum University Science Park Development Co. Ltd.Daqing163318China College of Petroleum Engineering Northeast Petroleum UniversityDaqing163318China

The turbidite channel of South China Sea has been highly *** by the complex fault and the rapid phase change of lithofacies,predicting the channel through conventional seismic attributes is not accurate *** response to this disadvantage,this study used a method combining grey relational analysis(GRA)and support vectormachine(SVM)and established a set of prediction technical procedures suitable for reservoirs with complex geological *** the case study of the Huangliu Formation in Qiongdongnan Basin,South China Sea,this study first dimensionalized the conventional seismic attributes of Gas Layer Group I and then used the GRA method to obtain the main relational factors.A higher relational degree indicates a higher probability of responding to the attributes of the turbidite *** study then accumulated the optimized attributes with the highest relational factors to obtain a first-order accumulated sequence,which was used as the input training sample of the SVM model,thus successfully constructing the SVM turbidite channel *** results prove that the GRA-SVMmethod has a high drilling coincidence *** the core and logging data and taking full use of the advantages of seismic inversion in predicting the sand boundary of water channels,this study divides the sedimentary microfacies of the Huangliu Formation in the Lingshui 17-2 Gas *** comprehensive study has shown that the GRA-SVM method has high accuracy for predicting turbidite channels and can be used as a superior turbidite channel prediction method under complex geological conditions.

关键词： Support vector machine channel Huangliu Formation Qiongdongnan Basin

Metagenomic Insight Reveals the Microbial Structure and Function of the Full-Scale Coking Wastewater Treatment System:Gene-Based Nitrogen Removal

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Engineering 2024年第5期36卷 76-89页

作者： Jiaying Ma Fan Wang Haifeng Fan Enchao Li Huaqiang Chu Xuefei Zhou Yalei Zhang State Key Laboratory of Pollution Control and Resource Reuse College of Environmental Science and EngineeringTongji UniversityShanghai 200092China Shanghai Institute of Pollution Control and Ecological Security Tongji UniversityShanghai 200092China Baowu Water Technology Co. Ltd.Shanghai 201999China

Microbial communities play crucial roles in pollutant removal and system stability in biological systems for coking wastewater(CWW)treatment,but a comprehensive understanding of their structure and functions is still lacking.A five month survey of four sequential bioreactors,anoxic 1/oxic 1/anoxic 2/oxic 2(A1/O1/A2/O2),was carried out in a full-scale CWW treatment system in China to elucidate operational performance and microbial *** results showed that A1/O1/A2/O2 had excellent and stable performance for nitrogen *** total nitrogen(TN;(17.38±6.89)mgL1)and ammonium-nitrogen(NH4 t-N;(2.10±1.34)mg·L^(-1))in the final biological effluent satisfied the Chinese national standards for *** analysis of 16S ribosome RNA(rRNA)sequencing and metagenomic sequencing showed that the bacterial communities and metagenomic function profiles of A1 and O1 shared similar functional structures,while those of A2 significantly varied from those of other bioreactors(pcore bacterial genera and nitrogen-cycling *** were the potential main participants in nitrogen metabolism in the A1/O1/A2/O2 system for CWW *** study prov

关键词： Coking wastewater Full-scale Microbial community Metagenomic sequencing Nitrogen-cycling genes Environmental factor

The Poset Cover Problem

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Open Journal of Discrete Mathematics 2013年第3期3卷 101-111页

作者： Lenwood S. Heath Ajit Kumar Nema core Quantative Strategies Goldman Sachs India Pvt. Ltd. Bangalore India Department of Computer Science Virginia Tech Blacksburg USA

A partial order or poset P=(X, on a (finite) base set X?determines the set L(P)?of linear extensions of P. The problem of computing, for a poset P, the cardinality of L(P)?is #P-complete. A set {P1,P2,...,Pk}?of posets on X?covers the set of linear orders that is the union of the L(Pi). Given linear orders L1,L2,...,Lm on X, the Poset Cover problem is to determine the smallest number of posets that cover {L1,L2,...,Lm}. Here, we show that the decision version of this problem is NP-complete. On the positive side, we explore the use of cover relations for finding posets that cover a set of linear orders and present a polynomial-time algorithm to find a partial poset cover.

关键词： Linear Orders Partial Orders NP-Completeness Algorithms

Segmented tomographic evaluation of structural degradation of carbon support in proton exchange membrane fuel cells

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Journal of Energy Chemistry 2022年第11期31卷 359-367,I0010页

作者： Jung A.Hong Min-Hyoung Jung Sung Yong Cho Eun-Byeol Park Daehee Yang Young-Hoon Kim Sang-Hyeok Yang Woo-Sung Jang Jae Hyuck Jang Hyo June Lee Sungchul Lee Hu Young Jeong Young-Min Kim Department of Energy Science Sungkyunkwan University(SKKU)Suwon 16419Republic of Korea Fuel Cell core Parts Development Cell Hyundai Mobis Co.Ltd.Uiwang 16082Republic of Korea Electron Microscopy&Spectroscopy Team Korea Basic Science Institute(KBSI)Daejeon 34133Republic of Korea Graduate School of Semiconductor Materials and Devices Engineering Ulsan National Institute of Science and Technology(UNIST)Ulsan 44919Republic of Korea

The variation of the three-dimensional(3D)structure of the membrane electrode of a fuel cell during proton exchange cycling involves the corrosion/compaction of the carbon *** increasing degradation of the carbon structure continuously reduces the electrocatalytic performance of proton exchange membrane fuel cells(PEM-FCs).This phenomenon can be explained by performing 3D tomographic analysis at the ***,conventional tomographic approaches which present limited experimental feasibility,cannot perform such evaluation and have not provided sufficient structural information with statistical significance thus ***,a reliable methodology is required for the 3D geometrical evaluation of the carbon ***,we propose a segmented tomographic approach which employs pore network analysis that enables the visualization of the geometrical parameters corresponding to the porous carbon structure at a high *** approach can be utilized to evaluate the 3D structural degradation of the porous carbon structure after cycling in terms of local surface area,pore size distribution,and their 3D *** geometrical parameters of the carbon body were demonstrated to be substantially reduced owing to the cycling-induced *** information enables a deeper understanding of the degradation phenomenon of carbon supports and can contribute to the development of stable PEM-FC electrodes.

关键词： Electron tomography Fuel cell Proton exchange membrane Membrane electrode assembly Carbon corrosion

Research on the quality deterioration of UHT milk products during shelf life:core microorganisms and related characteristics

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Food Science and Human Wellness 2024年第5期13卷 2866-2875页

作者： Ruixue Ding Kairu He Rina Wu Mengxue Lou Zhili Liu Yuqiong Piao Xiaoyan Liu Zhishen Mu Junrui Wu College of Food Science Shenyang Agricultural UniversityShenyang 110866China Shenyang Key Laboratory of Microbial Fermentation Technology Innovation Shenyang 110866China Liaoning Engineering Research Center of Food Fermentation Technology Shenyang 110866China Inner Mongolia Mengniu Dairy Grp.Co. Ltd.Hohhot 010000China

Commercial sterility does not guarantee the sustained stability of ultrahigh temperature(UHT)milk over 6 months shelf *** explore the microbiota presented in normal(SZ)and quality deteriorated UHT milk(QY and WY)products from the same *** on high-throughput sequencing research results,11 phyla and 54 genera were identified as dominant ***,Streptococcus,and Acinetobacter as core functional microbiota significantly influenced the UHT milk quality ***,principal component analysis(PCA)and multivariate analyses were used to examine the quality characteristics,including 11 physicochemical parameters,10 fatty acids,and 2 enzyme activities,in normal and quality deteriorated UHT *** found that the abundance of Pseudomonas increased in quality deteriorated milk(WY)and showed a significant positive correlation with heat-resistant protease *** in quality deteriorated milk(QY)also considerably contributed to the content of heat-resistant lipase,which resulted in spoilage deterioration of UHT milk.

关键词： Ultrahigh temperature(UHT) Quality deterioration High-throughput sequencing core functional microbiota Lipase Protease

Deciphering chemical and metabolite profiling of Chang-Kang-Fang by UPLC-Q-TOF-MS/MS and its potential active components identification

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Chinese Journal of Natural Medicines 2023年第6期21卷 459-480页

作者： YANG Fengge ZHANG Sihao TIAN Danmei ZHOU Guirong TANG Xiyang MIAO Xinglong HE Yi YAO Xinsheng TANG Jinshan Institute of Traditional Chinese Medicine and Natural Products College of Pharmacy/Guangdong Province Key Laboratory of Pharmacodynamic Constituents of Traditional Chinese Medicine and New Drug Research/International Cooperative Laboratory of Traditional Chinese Medicine Modernization and Innovative Drug Development of Ministry of Education(MOE)of ChinaJinan UniversityGuangzhou 510632China State Key Laboratory of core Technology in Innovative Chinese Medicine Tasly Pharmaceutical Group Co.Ltd.Tianjin 300410China Tasly Pharmaceutical Group Co. Ltd.Tianjin 300410China

Chang-Kang-Fang(CKF)formula,a Traditional Chinese Medicine(TCM)prescription,has been widely used for the treatment of irritable bowel syndrome(IBS).However,its potential material basis and underlying mechanism remain ***,this study employed an integrated approach that combined ultra-performance liquid chromatography-quadrupole time-of-flight mass spectrometry(UPLC-Q/TOF-MS)with network pharmacology to systematically characterize the phytochemical components and metabolites of CKF,as well as elucidating its underlying *** this comprehensive analysis,a total of 150 components were identified or tentatively characterized within the CKF ***,six N-acetyldopamine oligomers from Cicadae Periostracum and eight resin glycosides from Cuscutae Semen were characterized in this formula for the first ***,149 xenobiotics(58 prototypes and 91 metabolites)were detected in plasma,urine,feces,brain,and intestinal contents,and the in vivo metabolic pathways of resin glycosides were elaborated for the first ***,network pharmacology and molecular docking analyses revealed that alkaloids,flavonoids,chromones,monoterpenes,N-acetyldopamine dimers,p-hydroxycinnamic acid,and Cus-3/isomer might be responsible for the beneficial effects of CKF in treating IBS,and CASP8,MARK14,PIK3C,PIK3R1,TLR4,and TNF may be its potential *** discoveries offer a comprehensive understanding of the potential material basis and clarify the underlying mechanism of the CKF formula in treating IBS,facilitating the broader application of CKF in the field of medicine.

关键词： Chang-Kang-Fang Chemical profile Metabolites profile UPLC-Q-TOF/MS Network pharmacology Molecular docking