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High Voltage 2021年第2期6卷 242-254页

作者： Yunpeng liu Le li Hechen liu Xiaolin li Donggen liu Lei liu li tang Songsong Zhou Hebei Key Laboratory of Distributed Energy Storage and Micro-grid North China Electric Power UniversityBaodingChina Electric Power Research Institute of China Southern Power Grid GuangzhouChina China Electric Power Research Institute BeijingChina

In recent years,electrical breakdown accidents for composite cross-arms in rain-impacted environments have occurred which might be ascribed to the degradation of the tube-internally insulated foam materials *** research has focused on the different coupling agent treatments(KH-550,KH-560,KH-792,and IPTS)of the tube-internally insulated foam materials *** effect of different coupling agents on the inter-facial electrical and physical properties in a water environment have been *** leakage current and compressive shear strength of the interface were investigated after water diffusion ***-dimensional computed tomography(μCT)was used to study the interface cross-section tomogram,interface three-dimensional volume rendering,and relative interface *** interfacial hydrolysis resistance ability and the interfacial strength modified by various coupling agents were effectively reflected by the compressive shear strength and relatively defect *** results revealed the ranking of the comprehensive coupling effect was KH-560>KH-550>KH-792>IPTS,which provides significant guidance for modifying internal insulation interface performance for composite cross-arms.

关键词： composite interface coupling

Factors associated with breastfeeding duration:a prospective cohort study in Sichuan Province,China

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World Journal of Pediatrics 2015年第3期11卷 232-238页

作者： li tang Andy H Lee Colin W Binns School of Public Health Curtin UniversityPerthAustralia

Background:The World Health Organization(WHO)recommends exclusive breastfeeding for 6 months and continued breastfeeding thereafter with appropriate complementary foods for at least 2 years or *** study aimed to determine the factors associated with breastfeeding duration in Sichuan Province of ***:A prospective longitudinal study of 695 women,with a follow-up response rate of 71.9%,was conducted in Jiangyou,Sichuan Province in the period of *** were interviewed at discharge and followed up by telephone at 1,3,6 and 12 months *** duration was estimated by the Kaplan-Meier *** regression analyses were performed to identify factors associated with the breastfeeding ***:The median duration of"any breastfeeding"was 8.0[95%confidence interval(CI):7.8,8.2]*** age less than 25 years[adjusted hazard ratio(HR):1.61;95%CI:1.32,1.96]and maternal return to work before 6 months postpartum(adjusted HR:1.69;95%CI:1.32,2.17)were associated with a shorter duration of *** who delivered at hospital(adjusted HR:1.33;95%CI:1.05,1.67),introduced solid foods(adjusted HR:130;95%CI:1.02,1.64)and intended to stop breastfeeding within 6 months,or undecided how long to breastfeed(adjusted HR:1.41;95%CI:1.16,1.72),were more likely to terminate lactation within 1 ***:The duration of breastfeeding in Jiangyou was far below the recommendation of the *** programs targeting vulnerable subgroups of mothers should be provided in Sichuan to help them maintain breastfeeding as long as possible.

关键词： breastfeeding cohort study solid foods working mother

Hybrid position/force control strategy and experiment of the six-cable driven parallel manipulator for the forty-meter aperture radio telescope

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High Technology Letters 2012年第3期18卷 230-237页

作者： li Jian tang Xiaoqiang Shao Zhufeng Yao Rui Department of Precision Instruments and Mechanology Tsinghua University Beijing 100084 P. R. China

This paper mainly analyzes a hybrid position/force control strategy and experiment of a six-cable driven parallel manipulator for a forty-meter aperture radio telescope. Through the establishments of a kinematic model, a catenary model and a cable-force characteristics model, a basic method is presented based on preventing the pseudo-drag problem of a flexible cable and realizing the hybrid position/force control for a six-cable driven parallel manipulator, and a hybrid position/force control system is developed. Some specific experiments in two typical velocities for astronomical observations are carried out. Experimental results show that the tracking accuracy is related to the speed of the movement. The desired tracking accuracy of the support system is achieved through an effective hybrid position/force control strategy, the cable forces are controlled effectively, and the pseudo-drag problem of flexible cable is solved. This study establishes the foundation of achieving the harmonious movement of the six-cable driven parallel manipulator, A-B rotating platform and the Stewart fine tuninz olatform.

关键词： large radio telescope six-cable driven parallel manipulator hybrid position/forcecontrol tracking accuracy

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Intraocular lymphoma

International Journal of Ophthalmology(English edition) 2017年第8期10卷 1301-1307页

作者： li-Juan tang Chang-lin Gu Ping Zhang Department of Ocular Pathology State Key Laboratory of Ophthalmology Zhongshan Ophthalmic Center Sun Yat-sen University Guangzhou 510060 Guangdong Province China Department of Traditional Chinese Medicine the Second Health Service Center of Tangxia Tianhe District Guangzhou510665 Guangdong Province China

Intraocular lymphoma （IOL） is a rare lymphocytic malignancy which contains two main distinct forms. Primary intraocular lymphoma （PIOL） is mainly a sub- type of primary central nervous system lymphoma （PCNSL）. Alternatively, IOL can originate from outside the central nervous system （CNS） by metastasizJng to the eye. These tumors are known as secondary intraocular lymphoma （SlOL）. The IOL can arise in the retina, uvea, vitreous, Bruch＇s membrane and optic nerve. There are predominantly of B-cell origin; however there are also rare T-cell variants. Diagnosis remains challenging for ophthalmologists and pathologists, due to its ability to masquerade as noninfectious or infectious uveitis, white dot syndromes, or occasionally as other metastatic cancers. Laboratory tests include flow cytometry, immunocytochemistry, interleukin detection （IL-10： IL-6, ratio 〉1）, and polymerase chain reaction （PER） amplification. Methotrexate-based systemic chemotherapy with external beam radiotherapy and intravitreal chemotherapy with methotrexate are useful for controlling the disease, but the prognosis remains poor. Therefore, it is important to make an early diagnose and treatment. This review is focused on the clinical manifestations, diagnosis, treatment and prognosis of the IOL.

关键词： intraocular lymphoma central nervous system diagnosis treatment prognosis

A Possible Experimental Test on Five-Dimensional Gravitation Theory of Complex Field

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Communications in Theoretical Physics 2008年第2期49卷 382-384页

作者： WANG Yong-Jiu li Ai-Gen tang Zhi-Ming Institute of Physics Hunan Normal University Changsha 410081 China

By appropriately choosing additional dimensions of space-time, the mass spectrum of mesons is obtained, and the calculated results agree with the experimental data.

关键词： gravitation complex field experiment inspect

MMPP/M/C queue with congestion-based staffing policy and applications in operations of steel industry

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Journal of Iron and Steel Research International 2019年第7期26卷 659-668页

作者： Yan-he Jia li-xin tang Zhe George Zhang Xiao-feng Chen liaoning Key Laboratory of Manufacturing System and Logistics Institute of Industrial and Systems Engineering Northeastern University Shenyang 110819 Liaoning China Beedie School of Business Simon Fraser University Burnaby BC V5A 1S6 Canada Department of Decision Sciences Western Washington University Bellingham WA 98225 USA

A queueing model of the Markov-modulated Poisson process (MMPP) with thresholds was investigated. The customer arrival with various arrival rates in the model was viewed as the MMPP. In contrast to the Poisson, s arrival process, the MMPP can better describe the situation that the arrival rate changes with changing conditions;therefore, the model fits better with reality. The threshold conversion was added to the model based on the general MMPP/M/C model. When the number of customers in the system exceeds a threshold, all servers work to serve;when the number of customers in the system is less than another threshold, some servers are shut down. This is the congestion-based staffing policy with two thresholds. Specifically, the problems in the slab stocking stage of slab production at the Iron and Steel Complex in China were analysed. In the slab production process, because the rate of the upstream steelmaking is not constant, the rate of slab reaching the slab yard is uncertain. The crane service is used to store slabs in a warehouse. Because the slab arrival rate varies, different numbers of cranes in service need to be optimized for cost control. Thus, MMPP was used to describe slab arrival with varied arrival rates. Therefore, an MMPP/M/C queue with thresholds was used to analyse and solve the practical problems, and the optimal number of service cranes was obtained to minimize the cost of slab stocking.

关键词： Markov-modulated Poisson process Matrix geometry Congestion-based staffing policy Threshold conversion Slab Crane

An Aggregation Cache Replacement Algorithm Based on Ontology Clustering

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Wuhan University Journal of Natural Sciences 2006年第5期11卷 1141-1146页

作者： ZHU Jiang SHEN Qingguo tang tang li Yongqiang Institute of Communications Engineering PLAUniversity of Science and Technology Nanjing. 210007Jiangsu China

This paper describes the theory, implementation, and experimental evaluation of an Aggregation Cache Replacement （ ACR ） algorithm. By considering application background, carefully choosing weight values, using a special formula to calculate the similarity, and clustering ontologies by similarity for getting more embedded deep relations, ACR combines the ontology similarity with the value of object and decides which object is to be replaced. We demonstrate the usefulness of ACR through experiments. （a） It is found that the aggregation tree is created wholly differently according to the application cases. Therefore, clustering can direct the content adaptation more accurately according to the user perception and can satisfy the user with different preferences. （b） After comparing this new method with widely-used algorithm Last-Recently-Used （LRU） and First-in-First-out （FIFO） method, it is found that ACR outperforms the later two in accuracy and usability. （c） It has a better semantic explanation and makes adaptation more personalized and more precise.

关键词： ontology similarity replacement algorithm content adaptation semantic Web

Regulation of cell reprogramming by auxin during somatic embryogenesis

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aBIOTECH 2020年第3期1卷 185-193页

作者： li Ping tang Xian Sheng Zhang Ying Hua Su State Key Laboratory of Crop Biology College of Life SciencesShandong Agricultural UniversityTai’an 271018ShandongChina

How somatic cells develop into a whole plant is a central question in plant developmental *** powerful ability of plant cells is recognized as their *** embryogenesis is an excellent example and a good research system for studying plant cell ***,very little is known about the molecular basis of cell reprogramming from somatic cells to totipotent cells in this *** somatic embryogenesis from immature zygotic embryos in Arabidopsis,exogenous auxin treatment is required for embryonic callus formation,but removal of exogenous auxin inducing endogenous auxin biosynthesis is essential for somatic embryo(SE)*** expression of specific transcription factor genes,such as "LAFL" and BABY BOOM(BBM),can induce SEs without exogenous growth *** embryogenesis can also be triggered by stress,as well as by disruption of chromatin remodeling,including PRC2-mediated histone methylation,histone deacetylation,and PKL-related chromatin *** is evident that embryonic identity genes are required and endogenous auxin plays a central role for cell reprogramming during the induction of ***,we focus on reviewing the regulation of cell reprogramming for somatic embryogenesis by auxin.

关键词： Somatic embryogenesis Auxin Cell reprogramming Transcription factors Chromatin remodeling

Holographic Dark Energy Model is Consistent with Pantheon SN Ia Data

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Communications in Theoretical Physics 2019年第4期71卷 421-426页

作者： Xin li Su-Ping Zhao li tang Hai-Nan lin Department of Physics Chongqing University

We constrain three cosmological models,i.e.,ACDM model, holographic dark energy(HDE) model and R_h = ct model by using the recent Pantheon compilation of type la supernovae(SN la), the direction measurements of Hubble parameter H(z), and the baryon acoustic oscillations(BAO). The spatial curvature is considered in the ACDM model and the HDE model. We show that the HDE model in a spatially flat and HDE dominate universe has the same behavior as Rh = ct model if the characteristic parameter of the HDE model C_0 approaches to infinity. Numerical results show that the ACDM model is the best favoured one among the three models. The HDE model is consistent with observational data, the best fitting value of C_0 is around 0.8, which implies that the Rh = ct model should be modified to be compatible with the present cosmological observational data. Combing all the datasets, we give strict constraint on the Hubble constant,where h_0=0.694 ± 0.020 for the ACDM model and h_0= 0.689 ±0.019 for the HDE *** results imply that the tension of Hubble constant between Planck collaborations and Riess et al. has been partially relaxed. The constraint on the spatial curvature is also given,where Ω_(k0) =-0.066 ± 0.165 for the ACDM model andΩ_(k0)=0.029 ± 0.067 for the HDE model.

关键词： holographic dark energy cosmological observations supernova general

Insight into Biophysicochemical Principles of Biopolymers through Simulation and Theory

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Chinese Journal of Polymer Science 2023年第9期41卷 1342-1354,I0005页

作者： Hai-Xiao Wan Duo Xu Xue-Wei Dong Kai Yang li-tang Yan State Key Laboratory of Chemical Engineering Department of Chemical EngineeringTsinghua UniversityBeijing100084China Center for Soft Condensed Matter Physics and Interdisciplinary Research&School of Physical Science and Technology Soochow UniversitySuzhou215006China

The development of biopolymers for biomedical applications has traditionally been based on new ***,there is growing recognition that the biological responses can be regulated by the physical as well as the chemical properties of *** the biophysicochemical principles regarding biopolymers is thereby of great importance in the generation of advanced ***,this review article seeks to provide a conceptual framework demonstrating how the approaches of tailored computer simulations and theoretical analysis are harnessed to explore the physicochemical principles of biopolymer cellular *** briefly introduce the theoretical and simulation methods used in this field,summarize the typical findings based on these approaches,and describe the correlations between theoretical results and ***,the future prospects for the theoretical aspect of biopolymers and their biophysicochemical interactions are *** knowledge might be critical from the perspective of advantageous and safe use of designer biomaterials.

关键词： Biopolymers Computer simulation Theoretical analysis Biophysicochemical interaction Biophysics