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Energy consumption optimization for edge computing-supported cellular networks based on optimal transport theory

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Science China(Information Sciences) 2024年第2期67卷 201-218页

作者： Xiangyu LV Xiaohu GE Yi ZHONG qiang LI yong XIAO School of Electronic Information and Communications Huazhong University of Science and Technology

With advancements in mobile communication technologies, there have been multiple user device(UD) connections to cellular networks. Because of changes in the spatial distribution of UDs and application requirements, the traditional offloading mechanism based on the nearest distance will result in heavy loads for some base stations(BSs). Because there is a high-order relationship between the energy consumption of the BS processing tasks and the number of computing tasks, the traditional offloading mechanism will result in high energy consumption, and UD’s offloading decision must be dynamically adjusted. The offloading decision of UDs is optimized based on detailed information about various parameters associated with a network from the standpoint of distribution. This information includes details regarding the spatial distribution of UDs,application requirements, and the offloading period of computing tasks. Based on optimal transport theory,an energy consumption optimization algorithm is suggested to lower the total amount of energy consumed by the offloading process of UDs’ computing tasks by reasonably planning the offloading BSs of the UDs in the networks. The simulation results show that the proposed offloading mechanism based on energy consumption optimization reduces the total energy consumption of the offloading process by 28.09% when compared to the traditional offloading mechanism, and the traffic managed by each BS is balanced.

关键词： optimal transport theory edge computing energy consumption reduction dynamic voltage frequency scaling

Experimental and numerical study of hypervelocity impact damage on composite overwrapped pressure vessels

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Defence Technology（防务技术） 2024年第1期31卷 58-72页

作者： yong-Pan Duan Run-qiang Chi Bao-Jun Pang Yuan Cai Hypervelocity Impact Research Center Harbin Institute of TechnologyHarbin150080China College of Science Heilongjiang University of Science and TechnologyHarbin 150022China

Ground-based tests are important for studying hypervelocity impact(HVI)damage to spacecraft pressure vessels in the orbital debris environment.We analyzed the damage to composite overwrapped pressure vessels(COPVs)in the HVI tests and classified the damage into non-catastrophic damage and catastrophic damage.We proposed a numerical simulation method to further study non-catastrophic damage and revealed the characteristics and mechanisms of non-catastrophic damage affected by impact conditions and internal pressures.The fragments of the catastrophically damaged COPVs were collected after the tests.The crack distribution and propagation process of the catastrophic ruptures of the COPVs were analyzed.Our findings contribute to understanding the damage characteristics and mechanisms of COPVs by HVIs.

关键词： Orbital debris Hypervelocity impact Composite overwrapped pressure vessels Damage mechanisms

Gibberellin promotes cambium reestablishment during secondary vascular tissue regeneration after girdling in an auxin-dependent manner in Populus

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Journal of Integrative Plant Biology 2024年第1期66卷 86-102页

作者： Yufei Zhang Lingyan wang Yuexin Wu Donghui wang Xin‐qiang He State Key Laboratory of Protein and Plant Gene Research School of Life SciencesPeking UniversityBeijing 100871China

Secondary vascular tissue(SVT)development and regeneration are regulated by phytohormones.In this study,we used an in vitro SVT regeneration system to demonstrate that gibberellin(GA)treatment significantly promotes auxin-induced cambium reestablishment.Altering GA content by overexpressing or knocking down ent-kaurene synthase(KS)affected secondary growth and SVT regeneration in poplar.The poplar DELLA gene GIBBERELLIC ACID INSENSITIVE(PtoGAI)is expressed in a specific pattern during secondary growth and cambium regeneration after girdling.Overexpression of PtoGAI disrupted poplar growth and inhibited cambium regeneration,and the inhibition of cambium regeneration could be partially restored by GA application.Further analysis of the PtaDR5:GUS transgenic plants,the localization of PIN-FORMED 1(PIN1)and the expression of auxin-related genes found that an additional GA treatment could enhance the auxin response as well as the expression of PIN1,which mediates auxin transport during SVT regeneration.Taken together,these findings suggest that GA promotes cambium regeneration by stimulating auxin signal transduction.

关键词： auxin cambium gibberellin Populus secondary vascular tissue regeneration

Impact of initial fluctuations and nuclear deformations in isobar collisions

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Nuclear Science and Techniques 2024年第6期35卷 155-162页

作者： Jian-Fei wang Hao-Jie Xu Fu-qiang wang Department of Modern Physics University of Science and Technology of ChinaHefei 230026China School of Science Huzhou UniversityHuzhou 313000China Strong-Coupling Physics International Research Laboratory(SPiRL) Huzhou UniversityHuzhou 313000China Department of Physics and Astronomy Purdue UniversityWest LafayetteIN 47907USA

Relativistic isobar^(96)_(44)Ru+^(96)_(44)Ru and^(96)_(40)Zr+^(96)_(40)Zrcollisions have revealed intricate differences in their nuclear size and shape,inspiring unconventional studies of nuclear structure using relativistic heavy ion collisions.In this study,we investigate the relative differences in the mean multiplicityR_()and the secondR_(ε2)and third-order eccentricityR_(ε3)between isobar collisions using initial state Glauber models.It is found that initial fluctuations and nuclear deformations have negligible effects on R_()in most central collisions,while both are important for the R_(ε2)and R_(ε3),the degree of which is sensitive to the underlying nucleonic or sub-nucleonic degree of freedom.These features,compared to real data,may probe the particle production mechanism and the physics underlying nuclear structure.

关键词： Relativistic isobar collisions Initial fluctuations Nuclear deformation

Long-term operation optimization of circulating cooling water systems under fouling conditions

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Chinese Journal of Chemical Engineering 2024年第1期65卷 255-267页

作者： Jiarui Liang yong Tian Shutong Yang yong wang Ruiqi Yin Yufei wang School of Chemical Engineering and Environment China University of PetroleumBeijing102249China CHN Energy Xinjiang Chemical Co. LTDUrumqi830092China College of Mechanical and Transportation Engineering China University of PetroleumBeijing 102249China

Fouling caused by excess metal ions in hard water can negatively impact the performance of the circulating cooling water system(CCWS)by depositing ions on the heat exchanger's surface.Currently,the operation optimization of CCWS often prioritizes short-term flow velocity optimization for minimizing power consumption,without considering fouling.However,low flow velocity promotes fouling.Therefore,it's crucial to balance fouling and energy/water conservation for optimal CCWS long-term operation.This study proposes a mixed-integer nonlinear programming(MINLP)model to achieve this goal.The model considers fouling in the pipeline,dynamic concentration cycle,and variable frequency drive to optimize the synergy between heat transfer,pressure drop,and fouling.By optimizing the concentration cycle of the CCWS,water conservation and fouling control can be achieved.The model can obtain the optimal operating parameters for different operation intervals,including the number of pumps,frequency,and valve local resistance coefficient.Sensitivity experiments on cycle and environmental temperature reveal that as the cycle increases,the marginal benefits of energy/water conservation decrease.In periods with minimal impact on fouling rate,energy/water conservation can be achieved by increasing the cycle while maintaining a low fouling rate.Overall,the proposed model has significant energy/water saving effects and can comprehensively optimize the CCWS through its incorporation of fouling and cycle optimization.

关键词： Computer simulation Circulating water system Fouling Concentration cycle Optimization Variable frequency drive

Improving Fatigue Properties of 316L Stainless Steel Welded Joints by Surface Spinning Strengthening

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Acta Metallurgica Sinica(English Letters) 2024年第5期37卷 840-854页

作者： Dongqiqiong wang qiang wang Xiaowu Li Zhefeng Zhang Department of Materials Physics and Chemistry School of Materials Science and Engineeringand Key Laboratory for Anisotropy and Texture of Materials(Ministry of Education)Northeastern UniversityShenyang 110819China Shi-Changxu Innovation Center for Advanced Materials Institute of Metal ResearchChinese Academy of SciencesShenyang 110016China College of Light Industry Liaoning UniversityShenyang 110036China

The surface spinning strengthening(3S)mechanism and fatigue life extension mechanism of 316L stainless steel welded joint were systematically elucidated by microstructural analyses and mechanical tests.Results indicate that surface gradient hardening layer of approximately 1 mm is formed in the base material through grain fragmentation and deformation twin strengthening,as well as in the welding zone composed of deformedδ-phases and nanotwins.The fatigue strength of welded joint after 3S significantly rises by 32%(from 190 to 250 MPa),which is attributed to the effective elimination of surface geometric defects,discrete refinement ofδ-Fe phases and the appropriate improvement in the surface strength,collectively mitigating strain localization and surface fatigue damage within the gradient strengthening layer.The redistributed fineδ-Fe phases benefited by strong stress transfer of 3S reduce the risk of surface weak phase cracking,causing the fatigue fracture to transition from microstructure defects to crystal defects dominated by slip,further suppressing the initiation and early propagation of fatigue cracks.

关键词： 316L stainless steel Welded joint Surface spinning strengthening Nanotwin Fatigue life

Enhancement of heavy metals desorption from the soil by eddy deep leaching in hydrocyclone

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Journal of Environmental Sciences 2024年第1期135卷 242-251页

作者： Ning wang Hao Lu Bo Liu Tai Xiong Jianping Li Hualin wang qiang Yang School of Mechanical and Power Engineering East China University of Science and TechnologyShanghai 200237China National Engineering Laboratory for High Concentration Refractory Organic Wastewater Treatment Technology East China University of Science and TechnologyShanghai 200237China

An eddy deep leaching technology was developed in this paper to address the challenge of treating heavy metal contaminants in industrial mining areas.The desorption effect of As,Cd,Sb and Pb was investigated utilizing chemical leaching and physical eddy techniques.It was found that the heavy metals concentration increased with decreasing particle size.The highest proportion of Cd in the form distribution of soil was in the bound to iron and manganese oxides,while the maximum proportion of As,Sb and Pb were in the residual.The optimal solid-liquid ratio of the hydrocyclone was 1:20,and the corresponding separation efficiency and flow rate were 84.7%and 1.76 m^(3)/hr,respectively.The grade efficiency of soil particle separation increases with particle size and exceeds 99%for particles above 1,000μm.Leaching experiments have revealed that oxalic acid(OA)and a combination of oxalic acid and EDTA(OAPE)were more efficient than citric acid(CA)and a combination of citric acid and EDTA(CAPE)for the desorption of heavy metals,respectively.The comparison of OAPE and eddy leaching found that the latter improved the desorption efficiency by 9.4%,7.5%,7.2%and 7.8%for As,Cd,Sb and Pb compared to the former,respectively.The results demonstrated that the eddy leaching technique could further enhance the desorption efficiency of heavy metals.It is expected to provide technical support for soil remediation with reduced usage of leaching agents.

关键词： Heavy metals Soil remediation Oxalic acid Eddy leaching Hydrocyclone

Supplementary inferior phrenic artery embolization in the interventional treatment of hemoptysis

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Chinese Medical Journal 2009年第5期122卷 514-520页

作者： LIU Feng-yong wang Mao-qiang FAN Qing-sheng DUAN Feng wang Zhi-jun SONG Peng Department of Interventional Radiology Clinical Division of Medicine Chinese People's Liberation Army General Hospital Beijing 100853 China

Background Transcatheter bronchial artery embolization （BAE） is widely used for the treatment of hemoptysis and the immediate success rate is high, but there are still some hemorrhage recurrences. One of the common reasons for failure of BAE is collateral branches as blood supply. The inferior phrenic artery （IPA） is one of the most common collateral branches that is scarcely reported. Our purpose was to observe manifestations of IPA supplying to hemoptysis and evaluate the efficacy and safety of IPA embolization. Methods Angiography during interventional treatment of 178 hemoptysis patients in the past 7 years confirmed that IPA hemorrhage resulted in hemoptysis in 25 patients （26-67 years old） who had： lung cancer （11 patients）, bronchiectasis （11 patients）, chronic lung inflammation （2 patients）, and pulmonary tuberculosis （1 patient）. Among the 25 patients, 7 patients had twice interventional operations within one week and 6 patients still experienced intraoperative hemoptysis after conventional embolization of the bronchial artery, the internal thoracic artery, and the intercostal artery, then had the second interventional operation immediately. The total number of cases were 191. Selective embolization of the IPA was performed using polyvinyl alcohol microspheres, gelatin sponge particles, and microcoil. The safety and clinical significance of IPA embolization were evaluated. The Pearson X2 test and Fisher＇s exact probability test were used in this study. Results Selective IPA angiography showed increased diameter of the IPA, disorganization of the branches, and varying degrees of angiogenesis. In 11 cases, contrast material was seen in vessels supplying the tumor and in the tumor. In 9 cases, contrast material had leaked into the area supplied by the IPA; in 8 cases, non-specific flake-like deposits of contrast material were seen; and in 14 cases, abnormal communication or shunt was visualized. Lesions were closely related to the pleura in 25 patients. Fifteen lesions were close to the diaphragmatic pleura

关键词： hemoptysis inferior phrenic arteries angiography embolization, therapeutic

Endovascular embolization of pulmonary arteriovenous malformations

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Chinese Medical Journal 2010年第1期123卷 23-28页

作者： LIU Feng-yong wang Mao-qiang FAN Qing-sheng DUAN Feng wang Zhi-jun SONG Peng Department of Interventional Radiology Clinical Division ofInternal Medicine Chinese People's Liberation Army GeneralHospital Beijing 100853 China

Background The major consequence of pulmonary arteriovenous malformations （PAVMs） is the direct inflow of blood from the pulmonary artery to the pulmonary vein which induces hypoxemia. Severe complications include transient ischemic attacks, paradoxical embolization in the central nervous system, massive hemoptysis or hemothorax, etc. The conventional treatment is surgical intervention. However, this can be very traumatic and dangerous. Endovascular embolization has advantages over surgery such as a faithful therapeutic effect, a low complication rate, repeatability, etc. Methods Patients （n=-23） with symptomatic PAVMs underwent endovascular embolization; 11 were males and 12 were females, with ages ranging from 6 months to 58 years. During the embolization, microcoils were applied in 6 cases and standard steel coils were used in 17 cases. Results Multiple PAVMs lesions were found in 16 cases and single PAVMs lesion was found in 7 cases. Embolotherapy was carried out 28 times for 23 patients. The success rate was 100%. The results of pulmonary arteriography after treatment showed that single lesion disappeared completely while the main abnormal vessels in multiple lesions also disappeared. The mean blood oxygen saturation increased from （78.04＋8.22）% to （95.13＋3.67）% after the procedure. A correlated groups t test showed changes in blood oxygen saturation before and after embolization （t=9.101, P 〈0.001）. Symptoms of cardiac insufficiency disappeared in 5 cases and vascular murmur in the chest disappeared in 13 cases. After embolization, mild chest pain occurred in 11 cases, small amounts of pleural effusion occurred in 5 cases, and 1 patient died 2 months later because of a pyogenic infection secondary to the pulmonary infarction. Among the 22 remaining cases, with overall follow-up ranging from 18 months to 12 years, general conditions were fine, daily lives were normal and there were no neurologic symptoms or signs, except for 3 patients with diffused PAVMs who had persistent blood oxygen saturation between 85

关键词： pulmonary arteriovenous malformations pulmonary artery endovascular embolization pulmonary arteriography