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The load criteria for ship mechanical noise prediction in low frequencies and experimental validation

Journal of Ocean Engineering and Science 2023年第3期8卷 278-293页

作者： Xi-An Liu de-qing yang qing Li State Key Laboratory of Ocean Engineering School of Naval ArchitectureOcean and Civil EngineeringShanghai Jiao Tong UniversityShanghai 200240China

The loading method of the external excitations generated by the equipment directly affects the predicted result of the mechanical noise which should be the same under different excitation forms for the given equipment.In this paper,general load criteria are proposed to define forces/moments as the standard form and convert other forms of loads in the low-frequency domain.As the most typical form to charac-terize equipment excitation,acceleration load loading methods for different conditions are investigated.The equivalent formula between ideal accelerations and generalized forces establishes the first load cri-terion.The second load criterion is proposed to address the issue of an average acceleration loading,in which the phase and amplitude distribution are both absent,and cannot apply to the load identification.The upper and lower limits of the mechanical noise can be determined by the vibroacoustic transfer func-tion of the three load models,and the energy-averaged value is used to represent the mechanical noise.Furthermore,the third criterion is used to handle the case where the acceleration load is given by the results of a bench test.According to the equipment source descriptor invariance,the conversion method is achieved between the bench test and the real ship based on the transfer function of a load model,and the mechanical noise is predicted by an equivalent energy method.Finally,a three-parameter method to quantitatively evaluate the well-fitting of experimental and numerical results,and the load criteria are well validated by underwater acoustic experiments of an experimental model.

关键词： Ships’mechanical noise Load criteria Vibroacoustic transfer functions Underwater acoustic experiments Accelerations load Three-parameter method

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Numerical analysis method of ship-ice collision-induced vibration of the polar transport vessel based on the full coupling of ship-ice-water-air

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Journal of Ocean Engineering and Science 2023年第4期8卷 323-335页

作者： Yuan-He Shi de-qing yang Wen-Wei Wu State Key Laboratory of Ocean Engineering School of Naval Architecture Ocean and Civil EngineeringShanghai Jiao Tong UniversityShanghai 200240China Collaborative Innovation Center for Advanced Ship and deep-sea Exploration Shanghai Jiao Tong UniversityShanghai 200240China SJTU Yazhou Bay Institute of deepsea Science and Technology Sanya 572024China National Key Laboratory on Ship Vibration&Noise China Ship Scientific Research CenterWuxi 214082China

As the Arctic Channel continues to be developed,collisions between polar navigation vessels and sea ice are inevitable,which will directly affect structural safety and vibration comfort.However,the numerical analysis method of ship-ice collision-induced vibration is not perfect,and the effect of fluid coupling is not typically considered.In this paper,a simplified numerical analysis method for ship-ice collision-induced vibration is proposed,in which a reliable ice load is obtained by first performing ship-ice-water-air coupled collision calculations,followed by ship-ice-water coupled vibration calculations to obtain the vibration response of the structure.In addition,this paper investigates the full coupling method and the modeling ranges and meshing sizes involved in the analysis ship-ice collision-induced vibration,and the computational efficiencies of the traditional ALE algorithm and S-ALE algorithm are compared.The results indicate that the simplified simulation analysis method and gradient meshing model improve the calculation accuracy and efficiency in ship-ice collision and vibration response analysis.Moreover,the modeling range of the water and air models cannot be less than 6 times the ship width,2 times the ship length,and 1 times the ship depth,and the S-ALE algorithm saves 47.86%time compared to the ALE algorithm.The research results in this paper can provide a reference for the numerical simulation of ship-ice collision-induced vibration.

关键词： Ship–ice collision Ice-induced vibration Ship–ice–water–air coupling Fluid–structure interaction S-ALE algorithm Gradient meshing model

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Targeted multi-agent communication algorithm based on state control

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defence Technology（防务技术） 2024年第1期31卷 544-556页

作者： Li-yang Zhao Tian-qing Chang Lei Zhang Jie Zhang Kai-xuan Chu de-peng Kong department of Weaponry and Control Army Academy of Armored ForcesBeijing100072China Unit 92942 Beijing100161China

As an important mechanism in multi-agent interaction,communication can make agents form complex team relationships rather than constitute a simple set of multiple independent agents.However,the existing communication schemes can bring much timing redundancy and irrelevant messages,which seriously affects their practical application.To solve this problem,this paper proposes a targeted multiagent communication algorithm based on state control(SCTC).The SCTC uses a gating mechanism based on state control to reduce the timing redundancy of communication between agents and determines the interaction relationship between agents and the importance weight of a communication message through a series connection of hard-and self-attention mechanisms,realizing targeted communication message processing.In addition,by minimizing the difference between the fusion message generated from a real communication message of each agent and a fusion message generated from the buffered message,the correctness of the final action choice of the agent is ensured.Our evaluation using a challenging set of Star Craft II benchmarks indicates that the SCTC can significantly improve the learning performance and reduce the communication overhead between agents,thus ensuring better cooperation between agents.

关键词： Multi-agent deep reinforcement learning State control Targeted interaction Communication mechanism

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High patatin like phospholipase domain containing 8 expression as a biomarker for poor prognosis of colorectal cancer

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World Journal of Gastrointestinal Oncology 2024年第3期16卷 787-797页

作者： Peng-yang Zhou de-Xiang Zhu Yi-Jiao Chen qing-yang Feng Yi-Hao Mao Ao-Bo Zhuang Jian-Min Xu department of General Surgery Zhongshan Hospital Fudan UniversityShanghai 200032China

BACKGROUND Patatin like phospholipase domain containing 8(PNPLA8)has been shown to play a significant role in various cancer entities.Previous studies have focused on its roles as an antioxidant and in lipid peroxidation.However,the role of PNPLA8 in colorectal cancer(CRC)progression is unclear.AIM To explore the prognostic effects of PNPLA8 expression in CRC.METHODS A retrospective cohort containing 751 consecutive CRC patients was enrolled.PNPLA8 expression in tumor samples was evaluated by immunohistochemistry staining and semi-quantitated with immunoreactive scores.CRC patients were divided into high and low PNPLA8 expression groups based on the cut-off va-lues,which were calculated by X-tile software.The prognostic value of PNPLA8 was identified using univariate and multivariate Cox regression analysis.The over-all survival(OS)rates of CRC patients in the study cohort were compared with Kaplan-Meier analysis and Log-rank test.RESULTS PNPLA8 expression was significantly associated with distant metastases in our cohort(P=0.048).CRC patients with high PNPLA8 expression indicated poor OS(median OS=35.3,P=0.005).CRC patients with a higher PNPLA8 expression at either stage I and II or stage III and IV had statistically significant shorter OS.For patients with left-sided colon and rectal cancer,the survival curves of two PN-PLA8-expression groups showed statistically significant differences.Multivariate analysis also confirmed that high PNPLA8 expression was an independent prog-nostic factor for overall survival(hazard ratio HR=1.328,95%CI:1.016-1.734,P=0.038).

关键词： Biomarker Colorectal cancer Expression level Overall survival Patatin like phospholipase domain containing 8 Prognosis

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High-Superelasticity NiTi Shape Memory Alloy by Directed Energy deposition-Arc and Solution Heat Treatment

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Acta Metallurgica Sinica(English Letters) 2024年第1期37卷 132-144页

作者： Junyi Ma Lin Yu qing yang Jie Liu Lei yang State Key Laboratory of Materials Processing and Die&Mould Technology School of Materials Science and EngineeringHuazhong University of Science and TechnologyWuhan430070China School of Transportation and Logistics Engineering Wuhan University of TechnologyWuhan430074China

Directed energy deposition-arc(deD-Arc)technology has the advantages of simple equipment,low manufacturing cost and high deposition rate,while the use of deD-Arc has problems of microstructure inhomogeneity,position dependence of macroscopic mechanical properties and anisotropy.Therefore,it is necessary to carry out a subsequent heat treatment to improve its microstructure uniformity,mechanical properties and superelasticity.In this investigation,the deD-Arc 15-layer NiTi alloy thin-walled parts with the solution treatment at different process parameters were studied to analyze the effects of solution heat treatment on microstructure,phase composition,phase transformation,microhardness,tensile and superelasticity.The temperature range of solution treatment is 800-1050℃,and the treatment time range is 1-5.5 h.The results show that after solution treatment at 800℃/1 h,the content of precipitated phase decreases,the grain is refined,the microhardness increases,and the mechanical properties in the 0°direction are improved.The strain recovery rate after 10 tensile cycles has increased from 37.13%(as-built)to 49.25%(solid solution treatment).This research provides an effective post treatment method for high-performance deD-Arc NiTi shape memory alloys.

关键词： Directed energy deposition-arc(deD-Arc) Cold metal transfer(CMT) NiTi shape memory alloys Microstructure Phase transformation Solution heat treatment

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Coinfection with hepatic cystic and alveolar echinococcosis with abdominal wall abscess and sinus tract formation:A case report

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World Journal of Hepatology 2024年第2期16卷 279-285页

作者： Miao-Miao Wang Xiu-qing An Jin-Ping Chai Jin-Yu yang Ji-de A Xiang-Ren A School of Continuing Education Qinghai UniversityXining 810000Qinghai ProvinceChina department of Internal Medicine-Cardiovascular Qinghai Provincial People's HospitalXining 810007Qinghai ProvinceChina department of General Surgery Qinghai Provincial People's HospitalXining 810007Qinghai ProvinceChina department of Hepatic Hydatidosis Qinghai Provincial People's HospitalXining 810007Qinghai ProvinceChina department of Medical Laboratory Medicine Qinghai Provincial People's HospitalXining 810007Qinghai ProvinceChina

BACKGROUND Hepatic cystic and alveolar echinococcosis coinfections,particularly with concurrent abscesses and sinus tract formation,are extremely rare.This article presents a case of a patient diagnosed with this unique presentation,discussing the typical imaging manifestations of both echinococcosis types and detailing the diagnosis and surgical treatment experience thereof.CASE SUMMARY A 39-year-old Tibetan woman presented with concurrent hepatic cystic and alveolar echinococcosis,accompanied by abdominal wall abscesses and sinus tract formation.Initial conventional imaging examinations suggested only hepatic cystic echinococcosis,but intraoperative and postoperative pathological examination revealed the coinfection.Following radical resection of the lesions,the patient’s condition improved,and she was discharged soon thereafter.Subsequent outpatient follow-ups confirmed no recurrence of the hydatid lesion and normal surgical wound healing.Though mixed hepatic cystic and alveolar echinococcosis with abdominal wall abscesses and sinus tract formations are rare,the general treatment approach remains consistent with that of simpler infections of alveolar echinococcosis.CONCLUSION Lesions involving the abdominal wall and sinus tract formation,may require radical resection.Long-term prognosis includes albendazole and follow-up examinations.

关键词： Cystic echinococcosis Alveolar echinococcosis Abdominal wall abscess Surgical treatment Sinus tract Case report

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Review on regulation of MnS in non-qquenched and tempered steel

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Journal of Iron and Steel Research(International) 2024年第4期31卷 779-789页

作者： Guo-xing Qiu qing Du Feng Lu de-jun Miao Yong-kun yang Xiao-ming Li School of Metallurgical Engineering Xi'an University of Architecture and TechnologyXi'an 710055ShaanxiChina Laigang Technique Center Shandong Iron and Steel Group Co.Ltd.Jinan 271104ShandongChina

An overview of the current research status and control methods of MnS in non-quenched and tempered steel was provided.As a low-melting plastic inclusion,the morphology and distribution of MnS were influenced by various production processes.Therefore,control of MnS is a systematic problem that must be integrated into the entire production process.Based on the production process,the factors affecting the morphology and distribution of MnS in steel were introduced.The effects of oxygen activity,manganese,sulfur,and some alloys on MnS inclusion precipitation were summarized,mainly including MnS modification treatment and oxygen-sulfide composite precipitation control.It is believed that MnS precipitates during the solidification process of steel,and controlling the solidification cooling rate could effectively regulate the size and morphology of MnS,avoiding the precipitation of II-MnS.Additionally,by changing the deformation rate,deformation amount,deformation temperature during the hot deformation process,and heating time and temperature during heat treatment,the distribution and morphology of MnS could be improved.Through the fine control of the above process parameters,the number of II-MnS in steel could be effectively reduced,and their morphology could be improved,thereby enhancing the performance of non-quenched and tempered steel and promoting its wider application.Furthermore,applying laboratory research results to industrial production is an important direction for future research efforts in this field.

关键词： MnS Non-quenched and tempered steel Control technology Process parameter Morphology Distribution

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Influence of sintering time on microstructure and properties of hot oscillatory pressing sintered W–Cu refractory alloys

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Tungsten 2024年第2期6卷 323-332页

作者： Zi-Qian Wu Wei Zhao Ka Gao Shi-Hao Du qing-Quan Kong de-Jian Sun yang Gao School of Materials Science and Engineering Zhengzhou University of AeronauticsZhengzhou 450015China School of Mechanical Engineering University of Shanghai for Science and TechnologyShanghai 200093China department of General Medicine Changhai HospitalShanghai 200000China Hubei Key Laboratory of Mechanical Transmission and Manufacturing Engineering Wuhan University of Science and TechnologyWuhan 430081China Sichuan Province Engineering Technology Research Center of Powder Metallurgy Chengdu UniversityChengdu 610106China

W–Cu refractory alloys are widely used in aerospace,aviation,electronics,power,and other fi elds.However,because of its large melting point diff erence between alloy elements,the conventional powder metallurgy method required a long time of high temperature sintering is very likely to cause low density and abnormal grain size growth.Therefore,90W-10Cu refractory alloys were successfully prepared by hot oscillatory pressing(HOP)under diff erent sintering time in this work.Then the infl uence of sintering time on the microstructure,grain size,density,Vickers hardness,room-tensile property,and electrical conductivity of the W–Cu refractory alloy was systematically invested.The results showed that during the short sintering time(30–90 min),the density,Vickers hardness,tensile strength,and electrical conductivity of the W–Cu refractory alloy increased signifi cantly to 98.7%,163.29 HV 30,507.3 MPa,and 14.2%International Annealed Copper Standard with the sintering time increasing,respectively,while its grain size showed no obvious change.When the sintering time further increased to 120 min,the density was basically consistent with the sintering time of 90 min.Nevertheless,the prolonged high temperature sintering resulted in the grain growth of the samples,which caused the deterioration of the Vickers hardness,room-tensile strength,and conductivity properties of the W–Cu refractory alloy.At the same sintering time,the density,Vickers hardness,and electrical conductivity of the HOP sintered W–Cu refractory alloy were signifi cantly higher than those of the HP sintered sample.It was indicated that high density,fi ne-grain,and excellent properties W–Cu refractory alloys could be prepared by hot oscillatory pressing under appropriate sintering time.

关键词： W–Cu refractory alloy Hot oscillatory pressing Sintering time Microstructure Property

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Effect of alumina occurrence form on metallurgical properties of hematite and magnetite pellets

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Journal of Iron and Steel Research(International) 2024年第4期31卷 797-809页

作者： Jian Pan Chen-mei Tang Cong-cong yang de-qing Zhu Zheng-qi Guo Wei-qun Huang School of Minerals Processing and Bioengineering Central South UniversityChangsha 410083HunanChina Exploration and development of Geology and Mineral Resources Co. Ltd.Nanchang 330030JiangxiChina

The effect of alumina occurrence form on the metallurgical properties of both hematite and magnetite pellets was investigated at the same Al_(2)O level of 2 wt.%,including reduction index(RI),low-temperature reduction disintegration index(RDI),reduction swelling index(RSI),and high-temperature softening-dripping performance.The mineralogy of fired pellets was also studied to reveal the influence of alumina occurrence form on the phase composition and microstructure.From the results,the alumina occurrence form presents tremendous impacts on the metallurgical perfor-mance of both magnetite and hematite pellets.Addition of all alumina occurrence forms contributes to inferior reducibility of pellets,especially in the case of gibbsite for magnetite pellets with a RI of 58.4%and kaolinite for hematite pellets with a RI of 56.8%.However,addition of all alumina occurrence forms improves the RDI of magnetite pellets,while there is no significant difference among various alumina occurrence forms.In contrast,alumina occurrence forms have little influence on the RDI of hematite pellets.The presence of free alumina,gibbsite,and kaolinite tends to improve the RSI of hematite and magnetite pellets,whereas hercynite gives the opposite trend with a RSI of 25.6%.For softening-dripping performance of magnetite pellets,all alumina occurrence forms contribute to narrower softening-melting interval.Meanwhile,alumina,gibbsite,and kaolinite give narrower softening-dripping interval,at 229,217,and 88℃,respectively,whereas addition of hercynite results in the largest melting range at 276℃ due to its high melting point.Regarding hematite pellets,free alumina,gibbsite,and hercynite tend to enlarge melting range,whereas kaolinite contributes to lower dripping temperature of 1148℃ and narrow softening-dripping interval of 88℃ due to the formation of a greater amount of slag phase at high temperatures.

关键词： Oxidized pellet Magnetite Hematite Alumina occurrence form Metallurgical performance Blast furnace

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Investigation of Quantum Dot Color Filter Micro-LED Display

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Photonic Sensors 2024年第1期14卷 40-47页

作者： Xuhui PENG yang ZENG Sitao HUO Zhenyuan yang Xiaoping HUANG qing ZHAO School of Resources and Environment University of Electronic Science and Technology of ChinaChengdu 611731China yangtze delta Region Institute(Huzhou) University of Electronic Science and Technology of ChinaHuzhou 313001China Shanghai Tianma Microelectronics Shanghai 201201China

In this work,we present the investigation of the quantum dot color filter(QDCF)micro-light emitting diode(micro-LED)display.Green and red quantum dot photoresist(QDPR)materials are patterned into a pixelated array and precisely bonded with an all-blue micro-light emitting diode(micro-LED)substrate,forming a red,green,and blue(RGB)full color display through color conversion.A few factors that influence the achievable color gamut are further investigated.The resulting 1.1-inch 228-pixels per inch(ppi)display demo shows the good performance.The findings in this paper pave a way to the future industrialization of the micro-LED display.

关键词： Quantum dot color filter(QDCF) color conversion micro-light emitting diode(micro-LED) color gamut

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