检索结果-南通市图书馆

Using Improved Particle Swarm Optimization Algorithm for Location Problem of Drone Logistics Hub

同方期刊数据库博看期刊评论

在线全文

学校读者我要写书评

暂无评论

Computers, Materials & Continua 2024年第1期78卷 935-957页

作者： li zheng Gang Xu Wenbin Chen School of Mathematics and Computer Sciences Nanchang UniversityNanchang330031China

Drone logistics is a novel method of distribution that will become prevalent.The advantageous location of the logistics hub enables quicker customer deliveries and lower fuel consumption,resulting in cost savings for the company’s transportation operations.Logistics firms must discern the ideal location for establishing a logistics hub,which is challenging due to the simplicity of existing models and the intricate delivery factors.To simulate the drone logistics environment,this study presents a new mathematical model.The model not only retains the aspects of the current models,but also considers the degree of transportation difficulty from the logistics hub to the village,the capacity of drones for transportation,and the distribution of logistics hub locations.Moreover,this paper proposes an improved particle swarm optimization(PSO)algorithm which is a diversity-based hybrid PSO(DHPSO)algorithm to solve this model.In DHPSO,the Gaussian random walk can enhance global search in the model space,while the bubble-net attacking strategy can speed convergence.Besides,Archimedes spiral strategy is employed to overcome the local optima trap in the model and improve the exploitation of the algorithm.DHPSO maintains a balance between exploration and exploitation while better defining the distribution of logistics hub locations Numerical experiments show that the newly proposed model always achieves better locations than the current model.Comparing DHPSO with other state-of-the-art intelligent algorithms,the efficiency of the scheme can be improved by 42.58%.This means that logistics companies can reduce distribution costs and consumers can enjoy a more enjoyable shopping experience by using DHPSO’s location selection.All the results show the location of the drone logistics hub is solved by DHPSO effectively.

关键词： Drone logistics location problem mathematical model diversity particle swarm optimization

Effect of screening colonoscopy frequency on colorectal cancer mortality in patients with a family history of colorectal cancer

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

World Journal of Gastrointestinal Oncology 2024年第2期16卷 354-363页

作者： li zheng Bin li ling Lei li-Jia Wang Zhi-Ping Zeng Jian-Dong Yang Department of Gastroenterology The First Hospital of NanchangNanchang 330008Jiangxi ProvinceChina Department of General Surgery The First Hospital of NanchangNanchang 330008Jiangxi ProvinceChina

BACKGROUND Colorectal cancer is a common malignant tumor in China,and its incidence in the elderly is increasing annually.Inflammatory bowel disease is a group of chronic non-specific intestinal inflammatory diseases,including ulcerative colitis and Crohn’s disease.We included the clinicopathological and follow-up data of patients with colorectal cancer who underwent laparoscopic colectomy or open colectomy at our Gastrointestinal Department between January 2019 and December 2022.Surgical indicators,oncological indicators,and survival rates were compared between the groups.The results of 104 patients who met the above criteria were extracted from the database(laparoscopic colectomy group=63,open colectomy group=41),and there were no statistically significant differences in the baseline data or follow-up time between the two groups.RESULTS Intraoperative blood loss,time to first ambulation,and time to first fluid intake were significantly lower in the laparoscopic colectomy group than in the open colectomy group.The differences in overall mortality,tumor-related mortality,and recurrence rates between the two groups were not statistically significant,and survival analysis showed that the differences in the cumulative overall survival,tumor-related survival,and cumulative recurrence-free rates between the two groups were not statistically significant.CONCLUSION In elderly patients with colorectal cancer,laparoscopic colectomy has better short-term outcomes than open colectomy,and laparoscopic colectomy has superior long-term survival outcomes compared with open colectomy.

关键词： Colorectal cancer Laparoscopic surgery Open surgery Prognosis Laparoscopic colectomy Open colectomy

High-precision X-ray characterization for basic materials in modern high-end integrated circuit

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Journal of Semiconductors 2024年第7期45卷 12-24页

作者： Weiran Zhao Qiuqi Mo li zheng Zhongliang li Xiaowei Zhang Yuehui Yu National Key Laboratory of Materials for Integrated Circuits Shanghai Institute of Microsystem and Information TechnologyChinese Academy of SciencesShanghai 200050China School of Physical Science and Technology ShanghaiTech UniversityShanghai 201210China Shanghai Synchrotron Radiation Facility Shanghai Advanced Research InstituteChinese Academy of SciencesShanghai 201204China Beijing Synchrotron Radiation Facility Institute of High Energy PhysicsChinese Academy of ScienceBeijing 100049China

Semiconductor materials exemplify humanity's unwavering pursuit of enhanced performance,efficiency,and functionality in electronic devices.From its early iterations to the advanced variants of today,this field has undergone an extraordinary evolution.As the reliability requirements of integrated circuits continue to increase,the industry is placing greater emphasis on the crystal qualities.Consequently,conducting a range of characterization tests on the crystals has become necessary.This paper will examine the correlation between crystal quality,device performance,and production yield,emphasizing the significance of crystal characterization tests and the important role of high-precision synchrotron radiation X-ray topography characterization in semiconductor analysis.Finally,we will cover the specific applications of synchrotron radiation characterization in the development of semiconductor materials.

关键词： X-ray topography synchrotron radiation semiconductor materials crystal defects

Development and Validation of Diagnostic Criteria for Elderly Atopic Dermatitis

在线全文

学校读者我要写书评

暂无评论

International Journal of Dermatology And Venereology 2024年第1期07卷 1-5页

作者： Wang Shang-Shang li zheng Gu Chao-Ying Yin Hui-Bin Wu Yue-Meng Yao Xu li Wei Chinese Academy of Medical Sciences and Peking Union Medical College Nanjing Jiangsu 210042 Department of Dermatology Shanghai Institute of Dermatology Huashan Hospital Fudan University Shanghai 200040 China Department of Allergy and Rheumatology Jiangsu Key Laboratory of Molecular Biology for Skin Diseases and STIs Hospital for Skin Diseases (Institute of Dermatology)

Objective: Elderly atopic dermatitis (AD) is a newly identified subtype of AD. Whether specific diagnostic criteria are needed for elderly AD has been debated. This study aimed to propose diagnostic criteria for elderly AD and evaluate the sensitivity.Methods: A hospital-based study was conducted. We screened the clinical features of 1,312 patients with AD of different ages in 1 cohort and proposed a set of diagnostic criteria for elderly AD. The criteria were then validated in another cohort of 223 patients clinically diagnosed with elderly AD by dermatologists specialized in AD to examine the diagnostic sensitivity compared with other criteria by chi-square test.Results: Based on the patients’ clinical features, a set of diagnostic criteria for elderly AD were proposed. The new diagnostic criteria showed significantly higher sensitivity than the classical diagnostic criteria (P < 0.001), especially for mild and moderate AD (P < 0.001). Of all 223 patients with elderly AD, 93.3% fulfilled our criteria, while only 43.5%, 65.5%, and 52.0% fulfilled the Hanifin and Rajka criteria, the Japanese Dermatology Academy criteria, and the United Kingdom Working Party criteria, respectively.Conclusion: The newly proposed criteria for elderly AD yielded high diagnostic sensitivity, particularly for mild and moderate AD.

关键词： atopic dermatitis elderly diagnostic criteria sensitivity clinical features atypical

Recent progress in functional modification and crosslinking of bioprosthetic heart valves

在线全文

同方期刊数据库

学校读者我要写书评

暂无评论

Regenerative Biomaterials 2024年第1期3卷 1-16页

作者： Cheng zheng li Yang Yunbing Wang National Engineering Research Center for Biomaterials Sichuan UniversityChengdu 610064China

Valvular heart disease(VHD),clinically manifested as stenosis and regurgitation of native heart valve,is one of the most prevalent cardiovascular diseases with high mortality.Heart valve replacement surgery has been recognized as golden standard for the treatment of VHD.Owing to the clinical application of transcatheter heart valve replacement technic and the excellent hemodynamic performance of bioprosthetic heart valves(BHVs),implantation of BHVs has been increasing over recent years and gradually became the preferred choice for the treatment of VHD.However,BHVs might fail within 10-15 years due to structural valvular degeneration(SVD),which was greatly associated with drawbacks of glutaraldehyde crosslinked BHVs,including cytotoxicity,calcification,component degradation,mechanical failure,thrombosis and immune response.To prolong the service life of BHVs,much effort has been devoted to overcoming the drawbacks of BHVs and reducing the risk of SVD.In this review,we summarized and analyzed the research and progress on:(i)modification strategies based on glutaraldehyde crosslinked BHVs and(ii)nonglutaraldehyde crosslinking strategies for BHVs.

关键词： bioprosthetic heart valves modification crosslinking anticalcification antithrombosis

Piezoelectric composite hydrogel with wireless electrical stimulation enhances motor functional recovery of spinal cord injury

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Journal of Materials Science & Technology 2024年第5期172卷 228-239页

作者： Zehao li Guanlin li Xinyu Wang zheng Zhao State Key Laboratory of Advanced Technology for Materials Synthesis and Processing Wuhan University of TechnologyWuhan 430070China Sanya Science and Education Innovation Park of Wuhan University of Technology Sanya 572000China

Electrical stimulation(ES)can restore motor function after spinal cord injury(SCI).However,traditional intraspinal ES has many disadvantages,such as the need for a complex circuitry device,an external power source,and a second surgery to remove the implant.Piezoelectric materials have received increasing at-tention due to their potential to convert ambient mechanical energy into ES without an external power source or implantation of electrodes.Herein,a novel polydopamine(PDA)coated barium titanate(BaTiO_(3))nanoparticles(BaTiO_(3)@PDA)incorporated silk fibroin(SF)hydrogel(SFBT)was established.The SFBT hy-drogel was crosslinked by horseradish peroxidase(HRP)/hydrogel peroxide(H_(2)O_(2))to integrate the piezo-electric potency of BaTiO_(3)with the thermal sensitivity of HRP/H_(2)O_(2)for SCI recovery.The hydrogel con-taining 5%(w/v)BaTiO_(3)@PDA nanoparticles(SFBT-5),which was selected for in vivo study,exhibited a short gelation time(5 min),suitable storage modulus(925±35 Pa),and wireless ES(average current of 124 nA).Moreover,Basso-Beattie-Bresnahan(BBB)scores test and footprint analysis demonstrated that the SFBT-5 hydrogel successfully enhanced motor functional recovery of SCI.In histopathological assess-ments,the SFBT-5 hydrogel significantly accelerated spinal cord healing,as indicated by smaller lesion cavities(∼16.7%of the SCI group).Meanwhile,the SFBT-5 hydrogel accelerated neurogenesis,facilitated axon regrowth and synapse formation,and promoted remyelination.Overall,this study highlights the potential of piezoelectric hydrogels for SCI regeneration.

关键词： Silk fibroin Barium titanate Piezoelectric hydrogel Spinal cord injury Electrical stimulation

Transfer film effects induced by 3D-printed polyether-ether-ketone with excellent tribological properties for joint prosthesis

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Bio-Design and Manufacturing 2024年第1期7卷 43-56页

作者： Yang li Jibao zheng Changning Sun Dichen li State Key Laboratory for Manufacturing System Engineering School of Mechanical EngineeringXi’an Jiaotong UniversityXi’an 710054China National Medical Products Administration(NMPA)Key Laboratory for Research and Evaluation of Additive Manufacturing Medical Devices Xi’an Jiaotong UniversityXi’an 710054China

Based on the building principle of additive manufacturing,printing orientation mainly determines the tribological properties of joint prostheses.In this study,we created a polyether-ether-ketone(PEEK)joint prosthesis using fused filament fabrication and investigated the effects of printing orientation on its tribological properties using a pin-on-plate tribometer in 25% newborn calf serum.An ultrahigh molecular weight polyethylene transfer film is formed on the surface of PEEK due to the mechanical capture of wear debris by the 3D-printed groove morphology,which is significantly impacted by the printing orientation of PEEK.When the printing orientation was parallel to the sliding direction of friction,the number and size of the transfer film increased due to higher steady stress.This transfer film protected the matrix and reduced the friction coefficient and wear rate of friction pairs by 39.13%and 74.33%,respectively.Furthermore,our findings provide a novel perspective regarding the role of printing orientation in designing knee prostheses,facilitating its practical applications.

关键词： 3D printing orientation Transfer film Tribological properties Polyether-ether-ketone Knee prosthesis

Accurately tracking hypersonic gliding vehicles via an LEO mega-constellation in relay tracking mode

在线全文

学校读者我要写书评

暂无评论

Journal of Systems Engineering and Electronics 2024年第1期35卷 211-221页

作者： li Zhao WANG Yidi zheng Wei College of Aerospace Science and Engineering National University of Defense TechnologyChangsha 410073China

In order to effectively defend against the threats of the hypersonic gliding vehicles(HGVs),HGVs should be tracked as early as possible,which is beyond the capability of the ground-based radars.Being benefited by the developing megaconstellations in low-Earth orbit,this paper proposes a relay tracking mode to track HGVs to overcome the above problem.The whole tracking mission is composed of several tracking intervals with the same duration.Within each tracking interval,several appropriate satellites are dispatched to track the HGV.Satellites that are planned to take part in the tracking mission are selected by a new derived observability criterion.The tracking performances of the proposed tracking mode and the other two traditional tracking modes,including the stare and track-rate modes,are compared by simulation.The results show that the relay tracking mode can track the whole trajectory of a HGV,while the stare mode can only provide a very short tracking arc.Moreover,the relay tracking mode achieve higher tracking accuracy with fewer attitude controls than the track-rate mode.

关键词： target tracking mega-constellation hypersonic gliding vehicle(HGV) sensor selection observability analysis

Safe Motion Planning and Control Framework for Automated Vehicles with Zonotopic TRMPC

在线全文

学校读者我要写书评

暂无评论

Engineering 2024年第2期33卷 146-159页

作者： Hao zheng Yinong li ling zheng Ehsan Hashemi State Key Laboratory of Mechanical Transmissions College of Mechanical and Vehicle EngineeringChongqing UniversityChongqing 400044China Department of Mechanical Engineering University of AlbertaEdmontonAB T6G 2H5Canada

Model mismatches can cause multi-dimensional uncertainties for the receding horizon control strategies of automated vehicles(AVs).The uncertainties may lead to potentially hazardous behaviors when the AV tracks ideal trajectories that are individually optimized by the AV's planning layer.To address this issue,this study proposes a safe motion planning and control(SMPAC)framework for AVs.For the control layer,a dynamic model including multi-dimensional uncertainties is established.A zonotopic tube-based robust model predictive control scheme is proposed to constrain the uncertain system in a bounded minimum robust positive invariant set.A flexible tube with varying cross-sections is constructed to reduce the controller conservatism.For the planning layer,a concept of safety sets,representing the geometric boundaries of the ego vehicle and obstacles under uncertainties,is proposed.The safety sets provide the basis for the subsequent evaluation and ranking of the generated trajectories.An efficient collision avoidance algorithm decides the desired trajectory through the intersection detection of the safety sets between the ego vehicle and obstacles.A numerical simulation and hardware-in-the-loop experiment validate the effectiveness and real-time performance of the SMPAC.The result of two driving scenarios indicates that the SMPAC can guarantee the safety of automated driving under multi-dimensional uncertainties.

关键词： Automated vehicles Automated driving Motion planning Motion control Tube MPC Zonotope