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A FLEXIBLE OBJECTIVE-CONSTRAINT APPROACH AND A NEW ALGORITHM FOR CONSTRUCTING THE PARETO FRONT OF MULTIOBJECTIVE OPTIMIZATION PROBLEMS
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作者 N.HOSEINPOOR M.GHAZNAVI 《Acta Mathematica Scientia》 SCIE CSCD 2024年第2期702-720,共19页
In this article, a novel scalarization technique, called the improved objective-constraint approach, is introduced to find efficient solutions of a given multiobjective programming problem. The presented scalarized pr... In this article, a novel scalarization technique, called the improved objective-constraint approach, is introduced to find efficient solutions of a given multiobjective programming problem. The presented scalarized problem extends the objective-constraint problem. It is demonstrated that how adding variables to the scalarized problem, can lead to find conditions for (weakly, properly) Pareto optimal solutions. Applying the obtained necessary and sufficient conditions, two algorithms for generating the Pareto front approximation of bi-objective and three-objective programming problems are designed. These algorithms are easy to implement and can achieve an even approximation of (weakly, properly) Pareto optimal solutions. These algorithms can be generalized for optimization problems with more than three criterion functions, too. The effectiveness and capability of the algorithms are demonstrated in test problems. 展开更多
关键词 multiobjective optimization Pareto front SCALARIZATION objective-constraint approach proper efficient solution
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Development of a DFN-based probabilistic block theory approach for bench face angle design in open pit mining
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作者 Jianhua Yan Xiansen Xing +4 位作者 Zhihai Li Weida Ni Liuyuan Zhao Chun Zhu Yuanyuan He 《Journal of Rock Mechanics and Geotechnical Engineering》 SCIE CSCD 2024年第8期3047-3062,共16页
In open pit mining,uncontrolled block instabilities have serious social,economic and regulatory consequences,such as casualties,disruption of operation and increased regulation difficulties.For this reason,bench face ... In open pit mining,uncontrolled block instabilities have serious social,economic and regulatory consequences,such as casualties,disruption of operation and increased regulation difficulties.For this reason,bench face angle,as one of the controlling parameters associated with block instabilities,should be carefully designed for sustainable mining.This study introduces a discrete fracture network(DFN)-based probabilistic block theory approach for the fast design of the bench face angle.A major advantage is the explicit incorporation of discontinuity size and spatial distribution in the procedure of key blocks testing.The proposed approach was applied to a granite mine in China.First,DFN models were generated from a multi-step modeling procedure to simulate the complex structural characteristics of pit slopes.Then,a modified key blocks searching method was applied to the slope faces modeled,and a cumulative probability of failure was obtained for each sector.Finally,a bench face angle was determined commensurate with an acceptable risk level of stability.The simulation results have shown that the number of hazardous traces exposed on the slope face can be significantly reduced when the suggested bench face angle is adopted,indicating an extremely low risk of uncontrolled block instabilities. 展开更多
关键词 Open pit mine Bench face angle Block theory Probabilistic approach Discrete fracture network modeling Fractured rock slope
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Indication and surgical approach for reconstruction with endoprosthesis in bone-associated soft tissue sarcomas:Appropriate case management is vital
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作者 RecepÖztürk 《World Journal of Clinical Cases》 SCIE 2024年第12期2004-2008,共5页
It is important for surgeons performing sarcoma surgery to know that bone resection and tumor prosthesis applications in soft tissue sarcomas(STS)have unique features in terms of indication,surgical approach and follo... It is important for surgeons performing sarcoma surgery to know that bone resection and tumor prosthesis applications in soft tissue sarcomas(STS)have unique features in terms of indication,surgical approach and follow-up,in terms of the management of these cases.Some STS are associated with bone and major neurovascular structures.Bone-associated STS are generally relatively large and relatively deep-seated.Additionally,the tendency for metastasis is high.In some cases,the decision about which structures to resect is difficult.These cases are often accompanied by poor oncological and surgical outcomes.Management of cases should be done by a multidisciplinary team in advanced centers specialized in this field.The surgical team must have sufficient knowledge and experience in the field of limb-sparing surgery.Preoperative evaluation and especially good planning of bone and soft tissue reconstruction are vital. 展开更多
关键词 Soft tissue sarcoma Bone invasion Bone resection Endoprosthesis replacement PROStheSIS Limb salvage inDICATION approach
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Regional Brand and High-quality Development of Fruits in Ethnic Areas of the Yangtze River Economic Belt under the Greater Food Approach
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作者 Li GAO Jianjun ZHANG +2 位作者 Yuanpeng SUN Zhiyang LIU Zhiguo SUN 《Asian Agricultural Research》 2024年第3期1-7,共7页
Establishing the Greater Food Approach and promoting the Yangtze River Economic Belt s national major regional development strategy can better support and serve the agricultural power and Chinese-style modernization.T... Establishing the Greater Food Approach and promoting the Yangtze River Economic Belt s national major regional development strategy can better support and serve the agricultural power and Chinese-style modernization.This paper introduces the characteristics of fruit industry in 16 autonomous prefectures and 47 autonomous counties under the jurisdiction of the Yangtze River Economic Belt.It studies the intellectual property resources of brand marks from the aspects of geographical indications,collective trademarks,certification trademarks,well-known trademarks in China and national design patents,and analyzes the main problems of brand and high-quality development of fruit industry in these ethnic autonomous areas.Finally,it puts forward some strategies,such as improving the protection of intellectual property rights of geographical indications,using intellectual property rights of brand signs,building modern seed industry upgrading project,drawing lessons from the experience of thousand villages demonstration project,ensuring that large-scale poverty does not occur,and building a diversified food supply system. 展开更多
关键词 GREATER FOOD approach Fruit industry Regional brand the Yangtze River Economic Belt ETHNIC areas
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Change in the Number of Tropical Cyclone Landfall and Approach over Mozambique from 1980 to 2020
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作者 Dinis Chichava Jinhua Yu +1 位作者 Philemon Henry King’uza Samuel Ekwacu 《Journal of Geoscience and Environment Protection》 2024年第10期1-20,共20页
In this study, the variability of tropical cyclone (TC) landfall and approach over Mozambique as well as the environmental factors influencing were investigated. The frequencies of tropical cyclone landfall and approa... In this study, the variability of tropical cyclone (TC) landfall and approach over Mozambique as well as the environmental factors influencing were investigated. The frequencies of tropical cyclone landfall and approach as well as environmental factors were compared between the two periods (1980 to 1999 and 2000 to 2020). This study found that, according to International Best Track Archive for Climate Stewardship (IBTrACS) tropical cyclone data, the number of tropical cyclones making landfall over Mozambique increased by about 66% in the second period (2000-2020), compared to 34% in the first period (1980-1999). While the number of tropical cyclone approaches reduced from 59% in the first period to 41% in the second period. An assessment of the environmental conditions showed that warmer sea surface temperature (SST) and low vertical wind shear (VWS) were favorable to more TC genesis and, consequently, an increase in landfalls and a reduction in TC confined to the approach. 展开更多
关键词 Mozambique Tropical Cyclone Landfall Tropical Cyclone approach Environmental Conditions
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A Lane Change Model Considering the Stability of Cooperative Adaptive Cruise Control Platoon Fleet
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作者 Shunli Li Zengqiang Wang 《Proceedings of Business and Economic Studies》 2024年第5期7-12,共6页
In this article,lane change models for mixed traffic flow under cooperative adaptive cruise control(CACC)platoon formation are established.The analysis begins by examining the impact of lane changes on traffic flow st... In this article,lane change models for mixed traffic flow under cooperative adaptive cruise control(CACC)platoon formation are established.The analysis begins by examining the impact of lane changes on traffic flow stability.The influences of various factors such as lane change locations,timing,and the current traffic state on stability are discussed.In this analysis,it is assumed that the lane change location and the entry position in the adjacent lane have already been selected,without considering the specific intention behind the lane change.The speeds of the involved vehicles are adjusted based on an existing lane change model,and various conditions are analyzed for traffic flow disturbances,including duration,shock amplitude,and driving delays.Numerical calculations are provided to illustrate these effects.Additionally,traffic flow stability is factored into the lane change decision-making process.By incorporating disturbances to the fleet into the lane change income model,both a lane change intention model and a lane change execution model are constructed.These models are then compared with a model that does not account for stability,leading to the corresponding conclusions. 展开更多
关键词 Cooperative adaptive cruise control platoon lane change models STABILITY Traffic flow
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The Discourse-Historical Approach of Identity Construction in Corporate Promotional Videos for External Publicity Image
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作者 Xiaodong Wang Jing Yu 《Proceedings of Business and Economic Studies》 2024年第2期178-183,共6页
Corporate identity construction of external publicity image is an important part of the development of enterprises.Based on Wodak’s discourse-historical approach,this study takes the text of COFCO’s English promotio... Corporate identity construction of external publicity image is an important part of the development of enterprises.Based on Wodak’s discourse-historical approach,this study takes the text of COFCO’s English promotional video as the research object,analyzes the corporate brand image,media image,organizational image,and environmental image constructed by the enterprises from three steps:linguistic expression,discourse strategy,and theme to provide references for Chinese enterprises to enhance their international influence. 展开更多
关键词 Corporate promotional videos External publicity image Discourse-historical approach
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Clinical Outcome of Internal Fixation and Fusion in the Treatment of Spinal Fractures by Paraspinal Muscular Space Approach
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作者 Yafei Zhao Qiushuang Ma +3 位作者 Meng Zhang Shengwang Li Yannan Li Chenguang Tian 《Journal of Clinical and Nursing Research》 2024年第7期10-15,共6页
Objective:To explore the clinical effect of internal fixation and fusion with the paraspinal muscle gap approach in the treatment of spinal fracture patients.Methods:104 spinal fracture patients admitted to Central Ho... Objective:To explore the clinical effect of internal fixation and fusion with the paraspinal muscle gap approach in the treatment of spinal fracture patients.Methods:104 spinal fracture patients admitted to Central Hospital of TCM from October 2022 to April 2024 were selected as the study subjects and were randomly divided into the control group(n=52)and the observation group(n=52)according to the random number table method.The control group was treated with the conventional approach of internal fixation surgery,and the observation group was treated with the paraspinal muscular interspace approach of internal fixation fusion.The two groups’general data,surgical indexes,pain,lumbar spine function,and postoperative complications were observed.Results:The baseline data of the two groups of patients were not statistically significant(all P>0.05)while the intraoperative bleeding,the first postoperative time getting up from bed,and the length of hospital stay of the patients in the observation group were shorter than that of the control group(all P=0.000<0.001),and the duration of the operation was longer than that of the control group(t=2.644,P=0.010<0.05);at 3 months postoperatively,the VAS scores of the patients in the observation group were significantly lower than those in the control group(t=10.768,P=0.000<0.001),and the JOA score was higher than that of the control group(t=6.498,P=0.000<0.001);the total complication rate of patients in the observation group(3/5.77%)was significantly lower than that of the control group(12/23.08%)(χ^(2)=6.310,P=0.012<0.05).Conclusion:In the treatment of spinal fracture patients,compared with the conventional approach to internal fixation surgery,the paraspinal muscular gap approach to internal fixation and fusion treatment is less traumatic,postoperative lumbar spine function recovery is faster,and can reduce the incidence of postoperative complications. 展开更多
关键词 Paraspinal muscular interspace approach Fixation and fusion Spinal fracture
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Exploring the transformative impact of traditional Chinese medicine on depression:Insights from animal models 被引量:1
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作者 Yan Yang Yan-Kun Chen Meng-Zhou Xie 《World Journal of Psychiatry》 SCIE 2024年第5期607-623,共17页
Depression,a prevalent and complex mental health condition,presents a significant global health burden.Depression is one of the most frequent mental disorders;deaths from it account for 14.3%of people worldwide.In rec... Depression,a prevalent and complex mental health condition,presents a significant global health burden.Depression is one of the most frequent mental disorders;deaths from it account for 14.3%of people worldwide.In recent years,the integration of complementary and alternative medicine,including traditional Chinese medicine(TCM),has gained attention as a potential avenue for addressing depression.This comprehensive review critically assesses the efficacy of TCM interventions in alleviating depressive symptoms.An in-depth look at different research studies,clinical trials,and meta-analyses is used in this review to look into how TCM practices like herbal formulations,acupuncture,and mindbody practices work.The review looks at the quality of the evidence,the rigor of the methods,and any possible flaws in the current studies.This gives us an idea of where TCM stands right now in terms of treating depression.This comprehensive review aims to assess the efficacy of TCM interventions in alleviating depressive symptoms.In order to learn more about their possible healing effects,the study also looks into how different types of TCM work,such as herbal formulas,acupuncture,and mind-body practices. 展开更多
关键词 Traditional Chinese medicine DEPRESSION EFFICACY Treatment Holistic approach
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Which approach of total hip arthroplasty is the best efficacy and least complication? 被引量:1
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作者 Lertkong Nitiwarangkul Natthapong Hongku +3 位作者 Oraluck Pattanaprateep Sasivimol Rattanasiri Patarawan Woratanarat Ammarin Thakkinstian 《World Journal of Orthopedics》 2024年第1期73-93,共21页
BACKGROUND Total hip arthroplasty is as an effective intervention to relieve pain and improve hip function.Approaches of the hip have been exhaustively explored about pros and cons.The efficacy and the complications o... BACKGROUND Total hip arthroplasty is as an effective intervention to relieve pain and improve hip function.Approaches of the hip have been exhaustively explored about pros and cons.The efficacy and the complications of hip approaches remains inconclusive.This study conducted an umbrella review to systematically appraise previous meta-analysis(MAs)including conventional posterior approach(PA),and minimally invasive surgeries as the lateral approach(LA),direct anterior approach(DAA),2-incisions method,mini-lateral approach and the newest technique direct superior approach(DSA)or supercapsular percutaneouslyassisted total hip(SuperPath).AIM To compare the efficacy and complications of hip approaches that have been published in all MAs and randomized controlled trials(RCTs).METHODS MAs were identified from MEDLINE and Scopus from inception until 2023.RCTs were then updated from the latest MA to September 2023.This study included studies which compared hip approaches and reported at least one outcome such as Harris Hip Score(HHS),dislocation,intra-operative fracture,wound compliData were independently selected,extracted and assessed by two reviewers.Network MA and cluster rank and surface under the cumulative ranking curve(SUCRA)were estimated for treatment efficacy and safety.RESULTS Finally,twenty-eight MAs(40 RCTs),and 13 RCTs were retrieved.In total 47 RCTs were included for reanalysis.The results of corrected covered area showed high degree(13.80%).Among 47 RCTs,most of the studies were low risk of bias in part of random process and outcome reporting,while other domains were medium to high risk of bias.DAA significantly provided higher HHS at three months than PA[pooled unstandardized mean difference(USMD):3.49,95%confidence interval(CI):0.98,6.00 with SUCRA:85.9],followed by DSA/SuperPath(USMD:1.57,95%CI:-1.55,4.69 with SUCRA:57.6).All approaches had indifferent dislocation and intraoperative fracture rates.SUCRA comparing early functional outcome and composite complications(dislocation,intra-operative fracture,wound complication,and nerve injury)found DAA was the best approach followed by DSA/SuperPath.CONCLUSION DSA/SuperPath had better earlier functional outcome than PA,but still could not overcome the result of DAA.This technique might be the other preferred option with acceptable complications. 展开更多
关键词 Total hip arthroplasty Total hip replacement approach Supercapsular percutaneously-assisted total hip Harris Hip Score intra-operative fracture
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Pedestrian lane formation with following–overtaking model and measurement of system order
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作者 李碧璐 李政 +1 位作者 周睿 申世飞 《Chinese Physics B》 SCIE EI CAS CSCD 2024年第2期247-263,共17页
Pedestrian self-organizing movement plays a significant role in evacuation studies and architectural design.Lane formation,a typical self-organizing phenomenon,helps pedestrian system to become more orderly,the majori... Pedestrian self-organizing movement plays a significant role in evacuation studies and architectural design.Lane formation,a typical self-organizing phenomenon,helps pedestrian system to become more orderly,the majority of following behavior model and overtaking behavior model are imprecise and unrealistic compared with pedestrian movement in the real world.In this study,a pedestrian dynamic model considering detailed modelling of the following behavior and overtaking behavior is constructed,and a method of measuring the lane formation and pedestrian system order based on information entropy is proposed.Simulation and analysis demonstrate that the following and avoidance behaviors are important factors of lane formation.A high tendency of following results in good lane formation.Both non-selective following behavior and aggressive overtaking behavior cause the system order to decrease.The most orderly following strategy for a pedestrian is to overtake the former pedestrian whose speed is lower than approximately 70%of his own.The influence of the obstacle layout on pedestrian lane and egress efficiency is also studied with this model.The presence of a small obstacle does not obstruct the walking of pedestrians;in contrast,it may help to improve the egress efficiency by guiding the pedestrian flow and mitigating the reduction of pedestrian system orderliness. 展开更多
关键词 pedestrian movement lane formation information entropy order degree
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Stability-Considered Lane Keeping Control of Commercial Vehicles Based on Improved APF Algorithm
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作者 Bin Tang Zhengyi Yang +3 位作者 Haobin Jiang Ziyan Lin Zhanxiang Xu Zitian Hu 《Chinese Journal of Mechanical Engineering》 SCIE EI CAS CSCD 2024年第1期114-129,共16页
Regarding the lane keeping system,path tracking accuracy and lateral stability at high speeds need to be taken into account especially for commercial vehicles due to the characteristics of larger mass,longer wheelbase... Regarding the lane keeping system,path tracking accuracy and lateral stability at high speeds need to be taken into account especially for commercial vehicles due to the characteristics of larger mass,longer wheelbase and higher mass center.To improve the performance mentioned above comprehensively,the control strategy based on improved artificial potential field(APF)algorithm is proposed.In the paper,time to lane crossing(TLC)is introduced into the potential field function to enhance the accuracy of path tracking,meanwhile the vehicle dynamics parameters including yaw rate and lateral acceleration are chosen as the repulsive force field source.The lane keeping controller based on improved APF algorithm is designed and the stability of the control system is proved based on Lyapunov theory.In addition,adaptive inertial weight particle swarm optimization algorithm(AIWPSO)is applied to optimize the gain of each potential field function.The co-simulation results indicate that the comprehensive evaluation index respecting lane tracking accuracy and lateral stability is reduced remarkably.Finally,the proposed control strategy is verified by the HiL test.It provides a beneficial reference for dynamics control of commercial vehicles and enriches the theoretical development and practical application of artificial potential field method in the field of intelligent driving. 展开更多
关键词 lane keeping control Commercial vehicles Lateral stability Artificial potential field AIWPSO
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Analysis of the Energy and Environmental Sustainability of a Built Space System: The Case of Patte d’Oie University Campus in Ouagadougou
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作者 Daouda Sawadogo Ousmane Coulibaly +1 位作者 Xavier Chesneau Belkacem Zeghmati 《Energy and Power Engineering》 2024年第5期197-215,共19页
The aim of this study was to carry out a dynamic simulation of the energy and environmental performance of a built space system, with a view to assessing its energy and environmental class. The use of a simulation and... The aim of this study was to carry out a dynamic simulation of the energy and environmental performance of a built space system, with a view to assessing its energy and environmental class. The use of a simulation and modeling tool, supported by various methodological references, formed the basis of our approach. Adopting a systemic perspective, we described the structural and functional aspects of the systems making up built spaces, as well as the associated energy flows. Our approach was also based on a typology, taking into account typical days, structural and functional configurations at different scales and angles of observation. The analysis tool we developed in Java was applied to the built space system of the Patte d’Oie university campus in Ouagadougou. Annual electricity consumption was measured at 124387.34 kWh, closely aligned with the average annual electricity bill (125224.31 kWh), with a maximum relative deviation of 1%, followed by a carbon emission balance of 58337.66 kg eq CO<sub>2</sub> per year. This validation confirmed the effectiveness of our tool. In addition, following the analysis of electricity consumption using our tool, the university campus was classified in energy class B and environmental class C. These results will be based on the emission factors of the energy mix of the West African Economic and Monetary Union (WAEMU) territory, with particular emphasis on Burkina Faso. 展开更多
关键词 Energy Function Energy Class Carbon Footprint Built Space Consumption Item Systemic approach Typological approach
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Debate on direct-anterior vs posterior approach for hip hemiarthroplasty:The authors’insights
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作者 Deepak Kumar Tarkik Thami Manjunath Nishani 《World Journal of Orthopedics》 2024年第5期486-488,共3页
We read and discussed the study entitled“Complication rates after direct anterior vs posterior approach for Hip Hemiarthroplasty in elderly individuals with femoral neck fractures”with great interest.The authors hav... We read and discussed the study entitled“Complication rates after direct anterior vs posterior approach for Hip Hemiarthroplasty in elderly individuals with femoral neck fractures”with great interest.The authors have done justice to the topic of comparison of anterior and posterior surgical approaches for bipolar hemiarthroplasty which has been an everlasting debate in the existing literature.However,there are certain aspects of this study that need clarification from the authors. 展开更多
关键词 COMMENTARY Direct anterior approach Posterior approach Hip hemiarthroplasty
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Efficiency and safety of laparoscopic left hemihepatectomy: A study of intrathecal vs extrathecal Glissonean pedicle techniques
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作者 Li-Min Kang Lei Xu +2 位作者 Fu-Wei Zhang Fa-Kun Yu Li Lang 《World Journal of Gastrointestinal Surgery》 SCIE 2024年第8期2612-2619,共8页
BACKGROUND Selective hemihepatic vascular occlusion is utilized in both right and left hemihepatectomies to preserve blood supply to the intact lobe,maintain hemo-dynamic stability,and mitigate surgical risks.While th... BACKGROUND Selective hemihepatic vascular occlusion is utilized in both right and left hemihepatectomies to preserve blood supply to the intact lobe,maintain hemo-dynamic stability,and mitigate surgical risks.While this technique encompasses both intrathecal and extrathecal Glissonean pedicle transection methods,there is a lack of systematic comparative reports on these two approaches.AIM To retrospectively analyze the clinical data of patients with hepatocellular carcinoma(HCC)undergoing laparoscopic anatomical hepatectomy in our hospital to explore the feasibility,safety,and short-and long-term efficacy of extrathecal and intrathecal Glissonean pedicle transection methods in laparo-scopic left hemihepatectomy.METHODS A retrospective study was performed to analyze the clinical data of 49 HCC patients who underwent laparoscopic left hemihepatectomy from January 2019 to December 2022 in our hospital.These patients were divided into extrathecal Glissonean pedicle transection(EGP)group(n=24)and intrathecal Glissonean pedicle transection(IGP)group(n=25)according to the different approaches used for selective hemihepatic vascular occlusion.The perioperative indicators,liver function indexes,complications,and follow-up findings were compared between these two groups.RESULTS The surgeries were smooth in both groups,and no perioperative death was noted.The hepatic pedicle transection time and the operation time were(16.1±2.3)minutes and(129.6±19.0)minutes,respectively,in the EGP group,which were significantly shorter than those in the IGP group[(25.5±2.4)minutes and(184.8±26.0)minutes,respectively],both P<0.01.There were no significant differences in intraoperative blood loss,time to anal exhaust,hospital stay,drain indwelling time,and postoperative liver function between the two groups(all P>0.05).The incidence of postoperative complications showed no significant difference[16.67%(4/24)vs 16.0%(4/25),P>0.05].All the 49 HCC patients were followed up after surgery(range:11.2-53.3 months;median:36.4 months).The overall survival rate and disease-free survival rate were not significantly different(both P>0.05).CONCLUSION Both extrathecal and intrathecal Glissonean pedicle approaches are effective and safe hepatic inflow occlusion techniques in laparoscopic left hemihepatectomy for HCC.However,the extrathecal approach simplifies the hepatic pedicle transection,shortens the operation time,and increases the surgical efficiency,making it a more feasible technique. 展开更多
关键词 Hepatocellular carcinoma LAPAROSCOPY Extra-Glissonian approach intra-Glissonian approach Surgical efficiency Surgical safety
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Thermodynamic model for deoxidation of liquid steel considering strong metal-oxygen interaction in the quasichemical model framework
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作者 Yong-Min Cho Youn-Bae Kang 《International Journal of Minerals,Metallurgy and Materials》 SCIE EI CAS CSCD 2024年第5期988-1002,共15页
Herein,a thermodynamic model aimed at describing deoxidation equilibria in liquid steel was developed.The model provides explicit forms of the activity coefficient of solutes in liquid steel,eliminating the need for t... Herein,a thermodynamic model aimed at describing deoxidation equilibria in liquid steel was developed.The model provides explicit forms of the activity coefficient of solutes in liquid steel,eliminating the need for the minimization of internal Gibbs energy preliminarily when solving deoxidation equilibria.The elimination of internal Gibbs energy minimization is particularly advantageous during the coupling of deoxidation equilibrium calculations with computationally intensive approaches,such as computational fluid dynamics.The model enables efficient calculations through direct embedment of the explicit forms of activity coefficient in the computing code.The proposed thermodynamic model was developed using a quasichemical approach with two key approximations:random mixing of metallic elements(Fe and oxidizing metal) and strong nonrandom pairing of metal and oxygen as nearest neighbors.Through these approximations,the quasichemical approach yielded the activity coefficients of solutes as explicit functions of composition and temperature without requiring the minimization of internal Gibbs energy or the coupling of separate programs.The model was successfully applied in the calculation of deoxidation equilibria of various elements(Al,B,C,Ca,Ce,Cr,La,Mg,Mn,Nb,Si,Ti,V,and Zr).The limitations of the model arising from these assumptions were also discussed. 展开更多
关键词 deoxidation equilibria theRMODYNAMICS quasichemical approach computational fluid dynamics
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Experimental and numerical analyses of the effect of fibre content on the close-in blast performance of a UHPFRC beam
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作者 Junbo Yan Qiyue Zhang +4 位作者 Yan Liu Yingliang Xu Zhenqing Shi Fan Bai Fenglei Huang 《Defence Technology(防务技术)》 SCIE EI CAS CSCD 2024年第1期242-261,共20页
Limited research has been conducted on the influences of fiber content on close-in blasting characteristics for ultrahigh-performance fiber-reinforced concrete(UHPFRC)beams.This paper aims to address this knowledge ga... Limited research has been conducted on the influences of fiber content on close-in blasting characteristics for ultrahigh-performance fiber-reinforced concrete(UHPFRC)beams.This paper aims to address this knowledge gap through experimental and mesoscale numerical methods.Experiments were conducted on ten UHPFRC beams built with varying steel fiber volumetric fractions subjected to close-in explosive conditions.Additionally,this study considered other parameters,such as the longitudinal reinforcement type and ratio.In the case of UHPFRC beams featuring normal-strength longitudinal reinforcement of diametersΦ12,Φ16,andΦ20,a reduction in maximum displacement by magnitudes of19.6%,19.5%,and 17.4%was observed,respectively,as the volumetric fractions of fiber increased from1.0%to 2.5%.In addition,increasing the longitudinal reinforcement ratio and using high-strength steel longitudinal reinforcement both significantly reduced the deformation characteristics and increase the blasting resistances of UHPFRC beams.However,the effects on the local crushing and spalling damage were not significant.A mesoscale finite element model,which considers the impacts of fiber parameters on UHPFRC beam behaviors,was also established and well correlated with the test findings.Nevertheless,parametric analyses were further conducted to examine the impacts of the steel fiber content and length and the hybrid effects of various types of microfibers and steel fibers on the blasting performance of UHPFRC beams. 展开更多
关键词 Blast performance Close-in blast Fiber content Mesoscale approach UHPFRC beams
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Integrated hazard assessment of rockfall incidents in the Cap Aokas Cliff Region
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作者 Zohra LADJEL Farid ZAHRI +3 位作者 Riheb HADJI Younes HAMED Karim ZIGHMI Kaddour BENMARCE 《Journal of Mountain Science》 SCIE CSCD 2024年第6期1916-1929,共14页
Rock fall accidents in mountainous cliff areas have significant consequences for human life and transportation.This study aimed to evaluate the rockfall hazard in the Cap Aokas cliff region located along the northeast... Rock fall accidents in mountainous cliff areas have significant consequences for human life and transportation.This study aimed to evaluate the rockfall hazard in the Cap Aokas cliff region located along the northeast coast of Algeria by identifying the key factors contributing to rockfall occurrence.We employed a combination of kinematic analysis,Matterocking method,and 3D trajectory simulations to determine zones that are susceptible to rockfall mobilization.By using a probabilistic and structural approach in conjunction with photogrammetry,we identified the controlling factors.The kinematic analysis revealed the presence of five discontinuity families,which indicated both plane and wedge failure modes.The 3D trajectory simulations demonstrated that the falling blocks followed the stream direction.We then validated the susceptibility maps generated from the analysis using aerial photos and historical rockfall events.The findings of this study enhance our understanding of rockfall phenomena and provide valuable insights for the development of effective strategies to mitigate rockfall hazards. 展开更多
关键词 Trajectory simulations Probabilistic analysis Structural approach Rockfall hazard Cap Aokas cliff
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Presentation of the Berry-Tabor conjecture in Levy plates
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作者 Chao Li Guo-Lin Hou 《Chinese Physics B》 SCIE EI CAS CSCD 2024年第10期240-247,共8页
The Berry-Tabor(BT)conjecture is a famous statistical inference in quantum chaos,which not only establishes the spectral fluctuations of quantum systems whose classical counterparts are integrable but can also be used... The Berry-Tabor(BT)conjecture is a famous statistical inference in quantum chaos,which not only establishes the spectral fluctuations of quantum systems whose classical counterparts are integrable but can also be used to describe other wave phenomena.In this paper,the BT conjecture has been extended to Lévy plates.As predicted by the BT conjecture,level clustering is present in the spectra of Lévy plates.The consequence of level clustering is studied by introducing the distribution of nearest neighbor frequency level spacing ratios P(r),which is calculated through the analytical solution obtained by the Hamiltonian approach.Our work investigates the impact of varying foundation parameters,rotary inertia,and boundary conditions on the frequency spectra,and we find that P(r)conforms to a Poisson distribution in all cases.The reason for the occurrence of the Poisson distribution in the Lévy plates is the independence between modal frequencies,which can be understood through mode functions. 展开更多
关键词 Berry-Tabor conjecture frequency spectra Hamiltonian approach Lévy plates
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Probabilistic Analysis of Slope Using Finite Element Approach and Limit Equilibrium Approach around Amalpata Landslide of West Central, Nepal
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作者 Mahendra Acharya Khomendra Bhandari +2 位作者 Sandesh Dhakal Aasish Giri Prabin Kafle 《International Journal of Geosciences》 CAS 2024年第5期416-432,共17页
The stability study of the ongoing and recurring Amalpata landslide in Baglung in Nepal’s Gandaki Province is presented in this research. The impacted slope is around 200 meters high, with two terraces that have diff... The stability study of the ongoing and recurring Amalpata landslide in Baglung in Nepal’s Gandaki Province is presented in this research. The impacted slope is around 200 meters high, with two terraces that have different slope inclinations. The lower bench, located above the basement, consistently fails and sets others up for failure. The fluctuating water level of the slope, which travels down the slope masses, exacerbates the slide problem. The majority of these rocks are Amalpata landslide area experiences several structural disruptions. The area’s stability must be evaluated in order to prevent and control more harm from occurring to the nearby agricultural land and people living along the slope. The slopes’ failures increase the damages of house existing in nearby area and the erosion of the slope. Two modeling techniques the finite element approach and the limit equilibrium method were used to simulate the slope. The findings show that, in every case, the terrace above the basement is where the majority of the stress is concentrated, with a safety factor of near unity. Using probabilistic slope stability analysis, the failure probability was predicted to be between 98.90% and 100%. 展开更多
关键词 Finite Element approach Limit Equilibrium Method SLOPE Factor of Safety
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