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Lateral earth pressure of granular backfills on retaining walls with expanded polystyrene geofoam inclusions under limited surcharge loading 被引量:1
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作者 Kewei Fan Guangqing Yang +2 位作者 Weilie Zou Zhong Han Yang Shen 《Journal of Rock Mechanics and Geotechnical Engineering》 SCIE CSCD 2024年第4期1388-1397,共10页
Existing studies have focused on the behavior of the retaining wall equipped with expanded polystyrene(EPS)geofoam inclusions under semi-infinite surcharge loading rather than limited surcharge loading.In this paper,t... Existing studies have focused on the behavior of the retaining wall equipped with expanded polystyrene(EPS)geofoam inclusions under semi-infinite surcharge loading rather than limited surcharge loading.In this paper,the failure mode and the earth pressure acting on the rigid retaining wall with EPS geofoam inclusions and granular backfills(henceforth referred to as EPS-wall),under limited surcharge loading are investigated through two-and three-dimensional model tests.The testing results show that different from the sliding of almost all the backfill in the EPS-wall under semi-infinite surcharge loading,only an approximately triangular backfill slides in the wall under limited surcharge loading.The distribution of the lateral earth pressure on the EPS-wall under limited surcharge loading is non-linear,and the distribution changes from the increase of the wall depth to the decrease with the increase of the limited surcharge loading.An approach based on the force equilibrium of a differential element is developed to predict the lateral earth pressure behind the EPS-wall subjected to limited surcharge loading,and its performance was fully validated by the three-dimensional model tests. 展开更多
关键词 Retaining wall Expanded polystyrene(EPS)geofoam limited surcharge loading Lateral earth pressure Model test Prediction
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A Stroke-Limitation AMD Control System with Variable Gain and Limited Area for High-Rise Buildings
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作者 Zuo-Hua Li Qing-Gui Wu +1 位作者 Jun Teng Chao-Jun Chen 《Computer Modeling in Engineering & Sciences》 SCIE EI 2024年第1期865-884,共20页
Collisions between a moving mass and an anti-collision device increase structural responses and threaten structural safety.An active mass damper(AMD)with stroke limitations is often used to avoid collisions.However,a ... Collisions between a moving mass and an anti-collision device increase structural responses and threaten structural safety.An active mass damper(AMD)with stroke limitations is often used to avoid collisions.However,a strokelimited AMD control system with a fixed limited area shortens the available AMD stroke and leads to significant control power.To solve this problem,the design approach with variable gain and limited area(VGLA)is proposed in this study.First,the boundary of variable-limited areas is calculated based on the real-time status of the moving mass.The variable gain(VG)expression at the variable limited area is deduced by considering the saturation of AMD stroke.Then,numerical simulations of a stroke-limited AMD control system with VGLA are conducted on a high-rise building structure.These numerical simulations show that the proposed approach has superior strokelimitation performance compared with a stroke-limited AMD control system with a fixed limited area.Finally,the proposed approach is validated through experiments on a four-story steel frame. 展开更多
关键词 High-rise buildings active control stroke limitations variable gain variable limited area
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Exploring device physics of perovskite solar cell via machine learning with limited samples
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作者 Shanshan Zhao Jie Wang +8 位作者 Zhongli Guo Hongqiang Luo Lihua Lu Yuanyuan Tian Zhuoying Jiang Jing Zhang Mengyu Chen Lin Li Cheng Li 《Journal of Energy Chemistry》 SCIE EI CAS CSCD 2024年第7期441-448,共8页
Perovskite solar cells(PsCs)have developed tremendously over the past decade.However,the key factors influencing the power conversion efficiency(PCE)of PSCs remain incompletely understood,due to the complexity and cou... Perovskite solar cells(PsCs)have developed tremendously over the past decade.However,the key factors influencing the power conversion efficiency(PCE)of PSCs remain incompletely understood,due to the complexity and coupling of these structural and compositional parameters.In this research,we demon-strate an effective approach to optimize PSCs performance via machine learning(ML).To address chal-lenges posed by limited samples,we propose a feature mask(FM)method,which augments training samples through feature transformation rather than synthetic data.Using this approach,squeeze-and-excitation residual network(SEResNet)model achieves an accuracy with a root-mean-square-error(RMSE)of 0.833%and a Pearson's correlation coefficient(r)of 0.980.Furthermore,we employ the permu-tation importance(PI)algorithm to investigate key features for PCE.Subsequently,we predict PCE through high-throughput screenings,in which we study the relationship between PCE and chemical com-positions.After that,we conduct experiments to validate the consistency between predicted results by ML and experimental results.In this work,ML demonstrates the capability to predict device performance,extract key parameters from complex systems,and accelerate the transition from laboratory findings to commercialapplications. 展开更多
关键词 Perovskite solar cell Machine learning Device physics Performance prediction limited samples
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Data-driven methods for predicting the representative temperature of bridge cable based on limited measured data
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作者 WANG Fen DAI Gong-lian +2 位作者 HE Chang-lin GE Hao RAO Hui-ming 《Journal of Central South University》 SCIE EI CAS CSCD 2024年第9期3168-3186,共19页
Cable-stayed bridges have been widely used in high-speed railway infrastructure.The accurate determination of cable’s representative temperatures is vital during the intricate processes of design,construction,and mai... Cable-stayed bridges have been widely used in high-speed railway infrastructure.The accurate determination of cable’s representative temperatures is vital during the intricate processes of design,construction,and maintenance of cable-stayed bridges.However,the representative temperatures of stayed cables are not specified in the existing design codes.To address this issue,this study investigates the distribution of the cable temperature and determinates its representative temperature.First,an experimental investigation,spanning over a period of one year,was carried out near the bridge site to obtain the temperature data.According to the statistical analysis of the measured data,it reveals that the temperature distribution is generally uniform along the cable cross-section without significant temperature gradient.Then,based on the limited data,the Monte Carlo,the gradient boosted regression trees(GBRT),and univariate linear regression(ULR)methods are employed to predict the cable’s representative temperature throughout the service life.These methods effectively overcome the limitations of insufficient monitoring data and accurately predict the representative temperature of the cables.However,each method has its own advantages and limitations in terms of applicability and accuracy.A comprehensive evaluation of the performance of these methods is conducted,and practical recommendations are provided for their application.The proposed methods and representative temperatures provide a good basis for the operation and maintenance of in-service long-span cable-stayed bridges. 展开更多
关键词 cable-stayed bridges representative temperature gradient boosted regression trees(GBRT)method field test limited measured data
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Optimal timing of thoracic irradiation for limited stage small cell lung cancer:Current evidence and future prospects
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作者 Omer Sager Ferrat Dincoglan +9 位作者 Selcuk Demiral Hakan Gamsiz Bora Uysal Fatih Ozcan Onurhan Colak Esra Gumustepe Yelda Elcim Esin Gundem Bahar Dirican Murat Beyzadeoglu 《World Journal of Clinical Oncology》 CAS 2022年第2期116-124,共9页
Lung cancer is a global health concern as the leading cause of cancer related mortality worldwide.Small cell lung cancer(SCLC)poses a formidable challenge to the treating physicians with the worst prognosis among all ... Lung cancer is a global health concern as the leading cause of cancer related mortality worldwide.Small cell lung cancer(SCLC)poses a formidable challenge to the treating physicians with the worst prognosis among all lung cancers.However,limited stage SCLC(LS-SCLC)has a relatively better outcome with multimodality management.Efforts have been focused on optimal integration of treatment modalities to achieve an improved therapeutic ratio for patients with LS-SCLC.While chemotherapy and thoracic radiation therapy(TRT)are primary components of initial management for LS-SCLC,there is no consensus on optimal timing of TRT.Within this context,we herein provide a concise overview of current evidence and future prospects regarding the optimal timing of thoracic irradiation for LS-SCLC in light of the literature. 展开更多
关键词 Small cell lung cancer Thoracic irradiation limited stage small cell lung cancer Timing of thoracic radiation therapy Thoracic radiation therapy
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A Recursive Algorithm for Offspring's Genotype Frequency of Selfing Population on Multiple Alleles with Limited Loci 被引量:2
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作者 陈奇 李大林 《Agricultural Science & Technology》 CAS 2010年第6期26-27,41,共3页
This paper studies the offspring's genotype frequency of the selfing population on multiple alleles with limited loci.A recursive algorithm is given for it.It is discovered that the genotype frequency of homozygous g... This paper studies the offspring's genotype frequency of the selfing population on multiple alleles with limited loci.A recursive algorithm is given for it.It is discovered that the genotype frequency of homozygous gene of limited loci increases by generations.Relative increment reduces by generations and the genotype frequency tends to a definite value finally.The genotype frequency of limited loci with hybrid gene tends to 0 finally.But it is possibility that the genotype frequency increases in previous generations then reduces later.It is found that the number of the hybrid gene are more,the speeds tending to 0 are quicker. 展开更多
关键词 limited loci Multiple alleles SELFING POPULATION Genotype frequency
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Temperature Characteristics of Bilayer Thin-Film Devices Under Organic Interface Limited Current Conduction
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作者 杨青森 彭应全 +4 位作者 邢宏伟 李训栓 袁建挺 马朝柱 赵明 《Journal of Semiconductors》 EI CAS CSCD 北大核心 2008年第6期1075-1080,共6页
Temperature characteristics are important for the performance of organic thin film devices. On the basis of the hopping theory of Miller-Abrahams,an analytical model of charge transport for bilayer organic devices und... Temperature characteristics are important for the performance of organic thin film devices. On the basis of the hopping theory of Miller-Abrahams,an analytical model of charge transport for bilayer organic devices under the organicorganic interface limited current conduction is developed. The dependence of current, field,and carrier distribution in bilayer organic devices with the structure of "injection electrode/Layer Ⅰ/Layer Ⅱ/collection electrode" on temperature are numerically analyzed. We conclude that, for a given applied voltage, when temperature is raised, the voltage of LayerⅠ will increase,and the field will be higher. Meanwhile, the voltage of Layer Ⅲ will decrease, the field will become weaker accordingly,and the current of the device will increase. 展开更多
关键词 organic-organic interface limited temperature characteristics numerical analysis
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Study on Limited Filamentous Sludge Bulking Test in A/O Activated Sludge Process
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作者 万玉山 孙凌峰 +2 位作者 贾春霞 李娜 雷春生 《Agricultural Science & Technology》 CAS 2014年第9期1620-1623,共4页
[Objective] This study aimed to make use of the limited filamentous sludge bulking characteristics to purify water quality and save energy. [Method] The effects of dissolved oxygen (DO) on sludge bulking were explor... [Objective] This study aimed to make use of the limited filamentous sludge bulking characteristics to purify water quality and save energy. [Method] The effects of dissolved oxygen (DO) on sludge bulking were explored by changing the DO con- centration in the aerobiotic pool of NO system from the low load (0.25 kg COD/(kg MLSS.d)) and the medium to high load (0.55 kgCOD/(kg MLSSod)). [Result] In the NO activated sludge system, when the sludge load was 0.25 kg COD/(kg MLSS.d), DO=1.5 mg/L, the sludge index was at around 250, while when the sludge load- ing was 0.55 kg COD/(kg MLSS.d), DO=1.5 mg/L, the sludge index was close to 300, occurring the limited filamentous bulking. The bulked sludge still showed high removal rates to COD, SS, nitrogen and phosphorus. [Conclusion] It could improve the oxygen transfer rate and reduce the aeration rate at low DO conditions to achieve energy-saving. 展开更多
关键词 A/O process limited filamentous sludge bulking Sludge load Energy saving
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LIMITED MEMORY BFGS METHOD BY USING LINEAR INDEPENDENT SEARCH DIRECTIONS
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作者 倪勤 《Transactions of Nanjing University of Aeronautics and Astronautics》 EI 2001年第2期236-239,共4页
The degree of numerical linear independence is proposed and discussed. Based on this linear independence theory, a modified limited memory BFGS method is deve loped. Similar to the standard limited memory method, thi... The degree of numerical linear independence is proposed and discussed. Based on this linear independence theory, a modified limited memory BFGS method is deve loped. Similar to the standard limited memory method, this new method determines the new update by applying the updating formula m times to an initial positive diagonal matrix using the m previous pairs of the change in iteration and gradient. Besides the most recent pair of the change, which guarantees the quadratic termination, the choice of the other ( m -1) pairs of the change in the new method is dependent on the degree of numerical linear independence of previous search directions. In addition, the numerical linear independence theory is further discussed and the computation of the degree of linear independence is simplified. Theoretical and numerical results show that this new modified method improves efficiently the standard limited memory method. 展开更多
关键词 unconstrained optimization limited memory method BFGS method degree of linear independence
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新西兰品种权保护的域外扩张及我国的因应之策——兼评“Zespri Group Limited v Gao&Ors”案 被引量:1
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作者 李秀丽 《中国种业》 2020年第4期1-5,共5页
以“Zespri Group Limited v Gao&Ors”案判决书为研究视角,认为在侵权和损失认定方面,法官通过法律原则、国内外判例与学理学说的运用并通过解释立法目的,创造性地运用国内法律,影响其国外利益格局。该案将成为国内法域外适用向植... 以“Zespri Group Limited v Gao&Ors”案判决书为研究视角,认为在侵权和损失认定方面,法官通过法律原则、国内外判例与学理学说的运用并通过解释立法目的,创造性地运用国内法律,影响其国外利益格局。该案将成为国内法域外适用向植物新品种保护领域渗透的标志性事件。为维护我国自身利益,建议进一步做好植物新品种保护制度自身建设,加强植物新品种保护制度和植物遗传资源保护制度之间的协调。 展开更多
关键词 “Zespri GROUP limited V Gao&Ors”案 域外效力适用 植物品种权 遗传资源保护
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Combined treatment of phacoemulsification and single-port limited pars plana vitrectomy in acute angle-closure glaucoma 被引量:11
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作者 Ha Jeong Noh Seong Taeck Kim 《International Journal of Ophthalmology(English edition)》 SCIE CAS 2019年第6期974-979,共6页
AIM: To evaluate the efficacy of combined treatment of phacoemulsification(PE) and micro-incisional single-port transconjunctival limited pars plana vitrectomy(PPV) in acute angle-closure glaucoma(AACG).METHODS: A ret... AIM: To evaluate the efficacy of combined treatment of phacoemulsification(PE) and micro-incisional single-port transconjunctival limited pars plana vitrectomy(PPV) in acute angle-closure glaucoma(AACG).METHODS: A retrospective study included 26 patients who underwent PE diagnosed with AACG. Among them, 16 patients(16 eyes) underwent PE alone, 10 patients(10 eyes) underwent combined limited vitrectomy and PE. Then we compared intraocular pressure(IOP), anterior chamber angle, anterior chamber depth, central corneal thickness and corneal endothelial cell count before and after surgery, and effective PE time during cataract surgery.RESULTS: Effective PE time was shorter in the combined surgery group than in the single surgery group(P=0.040). There was no statistically significant difference in IOP and best-corrected visual acuity between the two groups postoperatively. At 6 mo postoperatively, there was no difference in the anterior chamber angle, anterior chamber depth, and central corneal thickness between two groups, but corneal endothelial cell count was higher in the combined surgery group than in the single surgery group(P=0.046). No complication such as vitreoretinal disease, endophthalmitis, bullous keratopathy was noted.CONCLUSION: Combined micro-incisional single-port transconjunctival limited PPV and PE are more effective and safer than PE alone because of less operation time and fewer complications for management of AACG. 展开更多
关键词 limited VITRECTOMY PHACOEMULSIFICATION acute ANGLE-CLOSURE glaucoma
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PERFORMANCE ANALYSIS OF POLLING SYSTEMS WITH LIMITED SERVICE 被引量:12
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作者 Zhao Dongfeng Li Bihai Zheng Sumin(Department of Information and Electronic Science, Yunnan University, Kunming 650091) 《Journal of Electronics(China)》 1998年第1期43-49,共7页
This paper analyzes a queue mode] of the polling system with limited service (K=1) in discrete time. By the imbedded Markov chain theory and the probability generating function method, the mean values of queue length ... This paper analyzes a queue mode] of the polling system with limited service (K=1) in discrete time. By the imbedded Markov chain theory and the probability generating function method, the mean values of queue length and message waiting time are explicitly obtained. Also, we give the simulation results. The results obtained by H. Tagai (1985) are revised. 展开更多
关键词 POLLING system limited SERVICE DISCRETE TIME
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Limited resection for duodenal gastrointestinal stromal tumors:Surgical management and clinical outcome 被引量:11
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作者 Jens Hoeppner Birte Kulemann +2 位作者 Goran Marjanovic Peter Bronsert Ulrich Theodor Hopt 《World Journal of Gastrointestinal Surgery》 SCIE CAS 2013年第2期16-21,共6页
AIM:To analyze our experience in patients with duodenal gastrointestinal stromal tumors(GIST) and review the appropriate surgical approach.METHODS:We retrospectively reviewed the medical records of all patients with d... AIM:To analyze our experience in patients with duodenal gastrointestinal stromal tumors(GIST) and review the appropriate surgical approach.METHODS:We retrospectively reviewed the medical records of all patients with duodenal GIST surgically treated at our medical institution between 2002 and 2011.Patient files,operative reports,radiological charts and pathology were analyzed.For surgical therapy open and laparoscopic wedge resections and segmental resections were performed for limited resection(LR).For extended resection pancreatoduodenectomy was performed.Age,gender,clinical symptoms of the tumor,anatomical localization,tumor size,mitotic count,type of resection resectional status,neoadjuvant therapy,adjuvant therapy,risk classification and follow-up details were investigated in this retrospective study.RESULTS:Nine patients(5 males/4 females) with a median age of 58 years were surgically treated.The median follow-up period was 45 mo(range 6-111 mo).The initial symptom in 6 of 9 patients was gastrointestinal bleeding(67%).Tumors were found in all four parts of the duodenum,but were predominantly located in the first and second part of the duodenum with each 3 of 9 patients(33%).Two patients received neoadjuvant medical treatment with 400 mg imatinib per day for 12 wk before resection.In one patient,the GIST resection was done by pancreatoduodenectomy.The 8 LRs included a segmental resection of pars 4 of the duodenum,5 wedge resections with primary closure and a wedge resection with luminal closure by Roux-Y duodeno-jejunostomy.One of these LRs was done minimally invasive;seven were done in open fashion.The median diameter of the tumors was 54 mm(14-110 mm).Using the Fletcher classification scheme,3/9(33%) tumors had high risk,1/9(11%) had intermediate risk,4/9(44%) had low risk,and 1/9(11%) had very low risk for aggressive behaviour.Seven resections showed microscopically negative transsection margins(R0),two showed positive margins(R1).No patient developed local recurrence during follow-up.The one patient who underwent pancreatoduodenectomy died due to progressive disease with hepatic metastasis but without evidence of local recurrence.Another patient died in complete remission due to cardiac disease.Seven of the nine patients are alive disease-free.CONCLUSION:In patients with duodenal GIST,limited surgical resection with microscopically negative margins,but also with microscopically positive margins,lead to very good local and systemic disease-free survival. 展开更多
关键词 GASTROINTESTINAL STROMAL tumor DUODENUM Surgery limited RESECTION SURVIVAL
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Application of internal fixation of steel-wire limited loop in early Achilles tendon rupture 被引量:10
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作者 Zhe Chen Jia-Sen Wei +3 位作者 Zhao-Yang Hou Jiong Hu Yan-Guang Cao Qi-Xin Chen 《Asian Pacific Journal of Tropical Medicine》 SCIE CAS 2013年第11期902-907,共6页
Objective:To explore the clinical effect and safety of internal fixation of steel-wire limited loop in early Achilles tendon rupture.Methods:Seventy-six patients respectively with early transected and avulsed types of... Objective:To explore the clinical effect and safety of internal fixation of steel-wire limited loop in early Achilles tendon rupture.Methods:Seventy-six patients respectively with early transected and avulsed types of Achilles tendon rupture were selected and treated with internal fixation of steel-wire limited loop.The patients began to take exercise for their lower limbs through continous passive motion as early as possible after surgical repair,and the loops were removed after 3-5 months.Six months later,the condition of complications including Achilles tendon re-rupture,wound fistula,wound infection and skin necrosis,cutaneous sensation in sural nerve dominance region,time back to preinjury work or learning as well as time to physical activities were observed.One year later,the therapeutic effect was evaluated,and the maximum circumferences of bilateral legs and raptured plane circumferences of Achilles tendon were measured.Results:The wound of all patients healed well,no complications like Achilles tendon re-rupture,wound fistula,wound infection and skin necrosis occured,and the cutaneous sensation in sural nerve dominance region was normal.The mean time back to preinjury work or learning as well as to pysical activities of all patients were respectively 10 and 22 weeks.Seventy out of 76 patients(92.1%) achieved an excellent effect,and 6(7.9%) good effect.The excellent and good rate came up to 100%.The maximum circumference in the affected leg decreased to 2 mm averagely compared with the offside,while the ruptured plane circumferences of Achilles tendon in the affected side increased to 2.2 mm compared with the offside.Conclusions:Kor early Achilles tendon rupture,internal fixation of steel-wire limited loop can recover the ankle function better,return to the preinjury state in the shortest lime,and has few complications. 展开更多
关键词 ACHILLES TENDON rupture Steel-wire limited LOOP Internal fixation ANKLE function
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Standardizing the classification of gastric cancer patients with limited and adequate number of retrieved lymph nodes:an externally validated approach using real-world data 被引量:2
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作者 Wei Wang Yu-Jie Yang +7 位作者 Ri-Hong Zhang Jing-Yu Deng Zhe Sun Sharvesh Raj Seeruttun Zhen-Ning Wang Hui-Mian Xu Han Liang Zhi-Wei Zhou 《Military Medical Research》 SCIE CAS CSCD 2022年第5期565-575,共11页
Background:Currently,there is no formal consensus regarding a standard classification for gastric cancer(GC)patients with<16 retrieved lymph nodes(rLNs).Here,this study aimed to validate a practical lymph node(LN)s... Background:Currently,there is no formal consensus regarding a standard classification for gastric cancer(GC)patients with<16 retrieved lymph nodes(rLNs).Here,this study aimed to validate a practical lymph node(LN)staging strategy to homogenize the nodal classification of GC cohorts comprising of both<16(Limited set)and≥16(Adequate set)rLNs.Methods:All patients in this study underwent R0 gastrectomy.The overall survival(OS)difference between the Limited and Adequate set from a large Chinese multicenter dataset was analyzed.Using the 8th American Joint Committee on Cancer(AJCC)pathological nodal classification(pN)for GC as base,a modified nodal classification(N’)resembling similar analogy as the 8th AJCC pN classification was developed.The performance of the proposed and 8th AJCC GC subgroups was compared and validated using the Surveillance,Epidemiology,and End Results(SEER)dataset comprising of 10,208 multi-ethnic GC cases.Results:Significant difference in OS between the Limited and Adequate set(corresponding N0–N3a)using the 8th AJCC system was observed but the OS of N0_(limited)vs.N1_(adequate),N1_(limited)vs.N2_(adequate),N2_(limited)vs.N3_(aadequate),and N3_(alimited)vs.N3_(badequate)subgroups was almost similar in the Chinese dataset.Therefore,we formulated an N’classification whereby only the nodal subgroups of the Limited set,except for pT1N0M0 cases as they underwent less extensive surgeries(D1 or D1+gastrectomy),were re-classified to one higher nodal subgroup,while those of the Adequate set remained unchanged(N’0=N0_(adequate)+pT1N0M0_(limited),N’1=N1_(adequate)+N0_(limited)(excluding pT1N0M0_(limited)),N’2=N2_(adequate)+N1_(limited),N’3a=N3_(aadequate)+N2_(limited),and N’3b=N3_(badequate)+N3_(alimited)).This N’classification demonstrated less heterogeneity in OS between the Limited and Adequate subgroups.Further analyses demonstrated superior statistical performance of the pTN’M system over the 8th AJCC edition and was successfully validated using the SEER dataset.Conclusion:The proposed nodal staging strategy was successfully validated in large multi-ethnic GC datasets and represents a practical approach for homogenizing the classification of GC cohorts comprising of patients with<16 and≥16 rLNs. 展开更多
关键词 Lymph nodes limited ADEQUATE Gastric cancer American Joint Committee on Cancer Tumor-node-metastasis Staging system Overall survival
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A LIMITED MEMORY QUASI-NEWTON METHOD FOR LARGE SCALE PROBLEM 被引量:3
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作者 邓卫兵 《Numerical Mathematics A Journal of Chinese Universities(English Series)》 SCIE 1996年第1期71-79,共9页
We study how to use the SR1 update to realize minimization methods for problems where the storage is critical. We give an update formula which generates matrices using information from the last m iterations. The numer... We study how to use the SR1 update to realize minimization methods for problems where the storage is critical. We give an update formula which generates matrices using information from the last m iterations. The numerical tests show that the method is efficent. 展开更多
关键词 LARGE SCALE PROBLEM limited MEMORY methods SR1 formula.
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Optimal Power Allocation with Limited Feedback of Channel State Information in Multi-User MIMO Systems 被引量:7
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作者 Kusi Ankrah Bonsu Weiwei Zhou +1 位作者 Su Pan Yan Yan 《China Communications》 SCIE CSCD 2020年第2期163-175,共13页
In this paper,an expression for the user’s achievable data rate in the multi-user multiple-input multiple-output(MU-MIMO)system with limited feedback(LF)of channel state information(CSI)is derived.The energy efficien... In this paper,an expression for the user’s achievable data rate in the multi-user multiple-input multiple-output(MU-MIMO)system with limited feedback(LF)of channel state information(CSI)is derived.The energy efficiency(EE)is optimized through power allocation under quality of service(QoS)constraints.Based on mathematical equivalence and Lagrange multiplier approach,an energy-efficient unequal power allocation(EEUPA)with LF of CSI scheme is proposed.The simulation results show that as the number of transmitting antennas increases,the EE also increases which is promising for the next generation wireless communication networks.Moreover,it can be seen that the QoS requirement has an effect on the EE of the system.Ultimately,the proposed EEUPA with LF of CSI algorithm performs better than the existing energy-efficient equal power allocation(EEEPA)with LF of CSI schemes. 展开更多
关键词 energy efficiency unequal power allocation limited feedback MU-MIMO QoSguarantee and precoding
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Exogenous application of glycine betaine improved water use efficiency in winter wheat(Triticum aestivum L.) via modulating photosynthetic efficiency and antioxidative capacity under conventional and limited irrigation conditions 被引量:3
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作者 Nazir Ahmed Yushi Zhang +3 位作者 Ke Li Yuyi Zhou Mingcai Zhang Zhaohu Li 《The Crop Journal》 SCIE CAS CSCD 2019年第5期635-650,共16页
Improving water use efficiency(WUE)is an important subject in agricultural irrigation for alleviating the scarcity of water resources in semiarid regions of the North China Plain.Moreover,glycine betaine(GB)is one of ... Improving water use efficiency(WUE)is an important subject in agricultural irrigation for alleviating the scarcity of water resources in semiarid regions of the North China Plain.Moreover,glycine betaine(GB)is one of the most effective compatible solutes synthesized naturally in plants for enhancing stress tolerance under abiotic stress,but little information is available on the involvement of GB in regulating crop WUE under field conditions.This study was conducted to explore the role of exogenously applied GB in improving WUE and plant physiological and biochemical responses inwinterwheat subjected to conventional or limited irrigation during the 2015–2016 and 2016–2017 growing seasons.Exogenous application of GB significantly enhanced antioxidant enzyme activities and reduced the accumulation ofmalondialdehyde and hydrogen peroxide under limited irrigation conditions.Furthermore,GB-treated plantsmaintained higher leaf relative water content andmembrane stability,which led to higher chlorophyll content and gas exchange attributes for better intrinsic and instantaneouswater use efficiencies compared to control plants under limited irrigation conditions.GB-treated plants had higher indole-acetic acid and zeatin riboside levels but lower ABA levels compared to control plants under conventional and limited irrigation conditions.Additionally,GB enhanced the grain filling rate and duration,grain number per spike,and final grainweight,which resulted in higher grain yield compared to the control.Interestingly,GB significantly improved the integrative and photosynthetic WUE under conventional and limited irrigation conditions,although GB treatment did not markedly affect total water consumption.These results suggest the involvement of GB in improving WUEs in winter wheat by modulating hormonal balance,membrane stability,photosynthetic performance and antioxidant systems to maintain higher grain yield under conventional and limited irrigation conditions. 展开更多
关键词 Winter wheat GLYCINE BETAINE Water use efficiency limited irrigation PHOTOSYNTHETIC performance Antioxidant systems
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Micro-arc Oxidation Inverter Power Supply Based on the Limited Bipolar Soft-switch Control Method 被引量:2
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作者 ZENG Min CHEN Xiaohong CAO Biao 《Chinese Journal of Mechanical Engineering》 SCIE EI CAS CSCD 2009年第3期390-394,共5页
In order to overcome many limitations of the conventional power supplies, such as ponderosity, big wastage, and simplex output characteristic, a dual-inverter power supply is designed to meet the different requirement... In order to overcome many limitations of the conventional power supplies, such as ponderosity, big wastage, and simplex output characteristic, a dual-inverter power supply is designed to meet the different requirements of micro-arc oxidation. The main circuit structure and principle of the dual-inverter power supply for micro-arc oxidation is described, the control system and the control adjustment method are also introduced. The dual-inverter technology is adopted in micro-arc oxidation power supply. The limited bipolar control mode is applied in the power inverter circuit for adjusting the voltage, and various voltage waveform can be obtained by controlling the chopper circuit. Meanwhile, the control accuracy and response speed are improved greatly because of the higher inverter frequency. The power supply can output direct current(DC) waveform, DC pulse waveform, symmetry alternating current(AC) waveform, asymmetry AC waveform, and so on. Besides, the parameters such as pulse width, range, frequency, duty cycle can be adjusted. The experimental result shows that the power supply has many advantages, such as stable output, wonderful waveform consistency and obvious advantage in technique, and it can meet the requirements of micro-arc oxidation process fully. 展开更多
关键词 micro-arc oxidation power supply INVERTER CHOPPER limited bipolar
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Simulation research on monomer agglomeration of nonmetallic inclusions in steel with a diffusion limited aggregation model 被引量:5
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作者 Hong Li Linxin Ning +3 位作者 Juan Wen Jiongming Zhang Yasushi Sasaki Mitsutaka Hino 《Journal of University of Science and Technology Beijing》 CSCD 2006年第2期117-120,共4页
The monomer agglomeration of nonmetallic inclusions was simulated with a diffusion limited aggregation (DLA) model of the fractal theory. The simulation study with a random two-dimensional diffusion was carried out.... The monomer agglomeration of nonmetallic inclusions was simulated with a diffusion limited aggregation (DLA) model of the fractal theory. The simulation study with a random two-dimensional diffusion was carried out. The results indicate that the DLA model can be used for the simulation of agglomeration behavior of the cluster-type inclusions. The morphology of clusters was observed with SEM and compared with the simulated agglomerates. The modelling procedure of the DLA model is applicable for the agglomeration process. The uncertainty of agglomeration process and the persuasive average agglomerative ratio was analyzed. The factors about the agglomerative ratio with the collision path distance and the size of particles or seed were discussed. The adherence of the nonmetallic inclusions on the dam, the weir and the walls of a tundish, and the absorption of inclusions by stopper or nozzle were also discussed. 展开更多
关键词 fractal theory diffusion limited aggregation (DLA) model monomer agglomeration agglomerative ratio nonmetallic inclusions
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