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Key Technologies and Applications of the Design and Manufacturing of Non-Circular TBMs

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Engineering 2017年第6期3卷 905-914页

作者： jianbin Li China Railway Hi-Tech Industry Corporation Limited Beijing 100070 China

With the rapid development of the exploitation of underground space, more and more large- or super- large-diameter tunnel-boring machines （TBMs） are being employed to construct underground space projects. At present, because conventional circular TBMs cannot completely meet the requirements of underground space exploitation regarding the cross-section and space-utilization ratio, non-circular TBMs. which are the tunneling equipment for an ideal cross-section, have become the new market growth point. This paper first presents the technical features and development status of non-circular TBMs. Next, in reference to typical projects and technological innovation, this paper investigates key techniques including shield design optimization, multi-cutterhead excavation, special-shaped segment erection, and soil conditioning in loess strata for a rectangular pipe-jacking machine and a horseshoe-shaped TBM, in order to provide a set of feasible solutions for the design, manufacture, and construction of non-circular TBMs. Relevant engineering practice shows that non-circular TBMs with customized design and manufacture have great advantages in terms of construction schedule, settlement control, and space utilization.

关键词： Non-circular TBMs Rectangular pipe-jacking machine Horseshoe-shaped TBM Underground space exploitation

DISPOSING THE LEFTOVERS UNDER THE CONSIGNMENT CONTRACT WITH REVENUE SHARING:RETAILER VS SUPPLIER

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Journal of Systems Science & Complexity 2012年第2期25卷 262-274页

作者： Wei HU jianbin LI School of Mathematical Sciences and LPMC Nankai University School of Management Huazhong University of Science and Technology

This paper studies the consignment contract with revenue sharing where the retailer offers two revenue share schemes between himself and his supplier from the viewpoint of inventory ownership: One is that the retailer takes charge of the unsold items,the other one is that the retailer returns the unsold items to the supplier at the end of the selling period,and the supplier disposes those *** each contract,the retailer deducts a percentage from the selling price for each sold item and transfers the balance to the *** supplier solves a two-stage problem:She first chooses contract,then decides retail price and delivery quantity according to the terms of the contract *** an iso-price-elastic demand model,the authors derive the retailer and suppliers’ optimal decisions for both *** addition,the authors characterize how they are affected by disposing *** authors compare the decisions between the two schemes for disposing cost turn out to be holding cost or salvage value,*** authors use numerical examples to show the supplier’s first-stage optimal decision depends critically on demand price elasticity,the disposing cost and the retailer’s share for channel cost.

关键词： Consignment sales revenue sharing stackelberg game supply chain management.

基于指数滤波模型的青藏高原根系层土壤水分估算研究

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高原气象 2025年第1期44卷 134-149页

作者：宋雨曦苏建宾文军郑东海成都信息工程大学大气科学学院高原大气与环境四川省重点实验室四川成都610225 中国科学院青藏高原研究所青藏高原地球系统与资源环境全国重点实验室国家青藏高原科学数据中心北京100101

高精度、长时序的土壤水分数据对青藏高原陆-气相互作用研究十分重要。然而,当前青藏高原土壤水分研究大多聚焦表层土壤水分的卫星反演,根系层土壤水分的估算研究相对匮乏。基于青藏高原五个土壤水分观测网络(狮泉河、帕里、那曲、黑河... 详细信息

高精度、长时序的土壤水分数据对青藏高原陆-气相互作用研究十分重要。然而,当前青藏高原土壤水分研究大多聚焦表层土壤水分的卫星反演,根系层土壤水分的估算研究相对匮乏。基于青藏高原五个土壤水分观测网络(狮泉河、帕里、那曲、黑河上游、玛曲)数据,本文系统评估了指数滤波模型在青藏高原不同气候与下垫面区域估算根系层(10 cm/20 cm/40 cm)土壤水分的适用性,探讨了不同环境因素(土壤、气候、植被)对模型特征时长参数T值的影响,最后评估了利用三种方法(各观测网络或青藏高原站点最优T值(Topt)中位数、随机森林模型)获取的区域T值估算青藏高原根系层土壤水分的可靠性。研究发现:(1)随着土壤深度的增加,根系层与表层土壤水分的相关性降低,而其空间异质性增大,导致指数滤波模型的应用精度降低,而模型T值及其空间异质性增大;(2)空间上随着降水量和土壤含水量的增加,根系层与表层土壤水分的相关性增大,而其空间异质性降低,使得指数滤波模型的应用精度上升,而其在区域内不同站点应用精度的差异呈现降低趋势;(3)土壤性质尤其是砂土含量是控制青藏高原区域T值空间分布的主要因素;(4)T值的获取对指数滤波模型在青藏高原的应用精度影响较小,当前常用的区域Topt中位数和随机森林模型均能获取相对合理的区域T值和取得一致且相对准确的模拟结果。本研究的发现有望推动利用指数滤波模型基于卫星表层土壤水分资料准确获取青藏高原根系层土壤水分。

关键词：青藏高原指数滤波模型根系层土壤水分不同气候与下垫面区域

OPTIMAL DECISIONS WHEN BALANCING EXPECTED PROFIT AND CONDITIONAL VALUE-AT-RISK IN NEWSVENDOR MODELS

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Journal of Systems Science & Complexity 2010年第6期23卷 1054-1070页

作者： Minghui XU jianbin LI School of Economics and Management Wuhan University Wuhan 430072 China. School of Management Huazhong University of Science and Technology Wuhan 430072 China.

This paper investigates a risk-averse inventory model by balancing the expected profit and conditional value-at-risk （CVaR） in a newsvendor model setting. We find out that： i） The optimal order quantity is increasing in the shortage cost for both the CVaR only criterion and the tradeoff objective, ii） For the case of zero shortage cost, the optimal order quantity to the CVaR criterion or tradeoff objective is increasing in the selling price, respectively. However, it may not be monotonic in the selling price when incorporating a substantial shortage cost. Moreover, it may be larger or less than the risk-neutral solution, iii） Under the tradeoff objective function, although the optimal order quantity for the model without shortage cost is increasing in the weight put on the expected profit, this property may not be true in general for the model with a substantial shortage cost. Some numerical examples are conducted to verify our results and observations.

关键词： Conditional value-at-risk newsvendor model risk aversion shortage cost.

Advances in thin film lubrication(TFL): From discovery to the aroused further researches

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Science China(Technological Sciences) 2015年第10期58卷 1609-1616页

作者： MA LiRan LUO jianbin State Key Laboratory of Tribology Tsinghua University

Thin film lubrication(TFL) is known as a mode of fluid-film lubrication regime bridging the gap between elastohydrodynamic lubrication(EHL) and boundary lubrication(BL). Since the first recorded literature published in 1995, TFL has become one of the landmarks in the development of lubrication theory over the last twenty years. This article presents an overview of the advances in the research of TFL regime. We first begin with a brief introduction of the discovery of the phenomenon, followed by the discussion of the relevant essential aspects, such as the performing approach, theory and physical model. The state-of-the-art studies on both the theoretical and experimental fields are also presented, also latter with emphasis on the review of researches in several promising applications.

关键词： thin film lubrication film thickness ordered structure interface

A head-to-toe makeover for classical sequencing-by-synthesis helps users to squeeze more out of each base

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National Science Review 2019年第1期6卷 3-4页

作者： jianbin Wang Angela Wu School of Life Sciences Tsinghua University Division of Life Science Hong Kong University of Science and Technology Department of Chemical and Biological Engineering Hong Kong University of Science and Technology

Today, many next-generation sequencing (NGS) methods, technologies and platforms have been developed that allow users to produce Tera base pairs of data in less than one day or ultralong reads covering multiple genes. By far the most popular NGS approach to date is cyclic sequencing-by-synthesis (SBS),whereby each DNA template’s complementary strand is synthesized by DNA polymerase and, as the new strand grows base by base, the identity of each

关键词： A head-to-toe makeover for classical sequencing-by-synthesis helps users to squeeze more out of each base

Thin film lubrication in the past 20 years

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Friction 2016年第4期4卷 280-302页

作者： Liran MA jianbin LUO State Key Laboratory of Tribology Tsinghua University Beijing 100084 China

Thin film lubrication (TFL),a lubrication regime that fills the gap between boundary lubrication (BL)and elastohydrodynamic lubrication (EHL) regimes,was proposed 20 years *** it was first recorded in the literature,TFL has gained substantial interest and has been advanced in the fields of theoretical and experimental *** the revelation of the TFL phenomenon and its central ideas,many studies have been *** paper attempts to systematically review the major developments in terms of both the history and the advances in *** begins with the description and definition of TFL,followed by the state-of-art studies on experimental technologies and their *** prospects of relevant studies and applications are also discussed.

关键词： thin film lubrication TFL thin EHL film ordered structure interface

Micro/atomic-scale vibration induced superlubricity

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Friction 2021年第5期9卷 1163-1174页

作者： Shuai SHI Dan GUO jianbin LUO State Key Laboratory of Tribology Tsinghua UniversityBeijing 100084China China Fortune Land Development Industrial Investment Co. Ltd.Beijing 100027China

With the rapid development of industry,the inconsistency between the rapid increase in energy consumption and the shortage of resources is becoming *** is one of the main causes of energy consumption;thus,the emergence of superlubricity technology can substantially improve the energy efficiency in motion *** this study,an efficient method to control superlubricity at the atomic‐scale is *** method employs vibrational excitation,which is called vibration induced superlubricity(VIS).The VIS can be easily and steadily achieved by employing external vibration in three *** simple method does not depend on the type of sample and *** of oscillation amplitude,frequency,scanning speed,and normal force(F_(N))on friction were *** and simulated explorations verified the practical approach for reducing energy dissipation and achieving superlubricity at the atomic‐scale.

关键词： superlubricity atomic‐scale vibration energy dissipation

Electrical bearing failures in electric vehicles

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Friction 2020年第1期8卷 4-28页

作者： Feng HE Guoxin XIE jianbin LUO State Key Laboratory of Tribology Department of Mechanical EngineeringTsinghua UniversityBeijing 100084China

In modern electric equipment,especially electric vehicles,inverter control systems can lead to complex shaft voltages and bearing *** an electric motor,many parts have electrical failure problems,and among which bearings are the most sensitive and vulnerable *** recent years,electrical failures in bearing have been frequently reported in electric vehicles,and the electrical failure of bearings has become a key issue that restricts the lifetime of all‐electric motor‐based power systems in a broader *** purpose of this review is to provide a comprehensive overview of the bearing premature failure in the mechanical systems exposed in an electrical environment represented by electric *** electrical environments in which bearing works including the different components and the origins of the shaft voltages and bearing currents,as well as the typical modes of electrical bearing failure including various topographical damages and lubrication failures,have been *** fundamental influence mechanisms of voltage/current on the friction/lubrication properties have been summarized and analyzed,and corresponding countermeasures have been ***,a brief introduction to the key technical flaws in the current researches will be made and the future outlook of frontier directions will be discussed.

关键词： electric vehicles bearing premature failure electrical environment shaft voltage