基于非参数估计方法的中国银行业不良贷款影子价格测算

不良贷款影子价格是呈现金融风险与收益关系的重要指标,研究其变化对银行业稳健发展和促进经济高质量发展至关重要。基于2007—2020年中国95家银行机构的面板数据,采用多维非参数前沿面和Meta-frontier模型,探究中国银行业不良贷款的影子价格及其变动趋势。研究发现,总体上中国银行业不良贷款影子价格在样本期内呈现下降趋势,银行业经营风险稳定下降;其中,政策性银行的风险管理意愿最高,其次为大型商业银行和股份制银行,最后是城市商业银行。研究结论为研判如何提高银行信贷资产质量,防范系统性金融风险提供重要依据。

基于特征正交分解的材料微结构参数化表征模型及等效性能优化设计

随着计算能力的不断发展,近年来基于材料微结构图像的材料等效性能数值模拟越来越受到学者们的重视.在此背景下,提出了一种针对材料微结构图像的高效参数化表征模型.通过特征正交分解(proper orthogonal decomposition,POD)对已有材料微结构图像数据进行特征分析,得到近似描述该类材料微结构的特征缩减基.应用移动最小二乘(moving least squares,MLS)法建立特征缩减基映射系数的响应面模型,拟合得到任意给定参量相应的缩减基映射系数.利用拟合缩减基系数可获得任意给定参量对应的微结构图像矩阵.该参数化表征模型被用于表征含椭球夹杂的两相材料(2-phase composite)的二维情形,并进一步应用于这类复合材料宏观等效力学性能的优化设计.

Port Integration in China: Temporal Pathways, Spatial Patterns and Dynamics

Over the past two decades, numerous ports located in China have participated in port integration strategies, thus influencing the entire port system. The current research is initiated in order to examine the nature of port integration in China, including associated temporal pathways, spatial patterns and dynamics. Results indicate that port integration in China has been characterized by a significant increase at the turn of the 21 st century, comprising thirteen distinguishable pathways typified by differing dynamics, particularly between the northern and southern ports. Pathways were found to include 44 seaports and river ports, chiefly concentrated in the Bohai Rim, Yangtze(Changjiang) River Delta, Beibu Gulf and the southeastern Fujian, thus representing significant spatial regions. Categorically larger seaports have become the primary beneficiaries of port integration. Integration cases were divided into four categories based upon quantified dynamic magnitude including the government-driven mode, market-driven mode, government/market-driven mode and strategic alliance, and into five further categories based upon spatial extent including port internal integration, jurisdictional port integration, port integration across neighbor region, regional port integration and hub-feeder port integration. Results suggest that several factors have effectively driven port integration in China, including legislative tools and spatial planning, optimization of shoreline resources and port functionality, and port competition with the same hinterland.

Spinal alignment evolution with age:A prospective gait analysis study

AIM To describe,using gait analysis,the development of spinal motion in the growing child.METHODS Thirty-six healthy children aged from 3 to 16 years old were included in this study for a gait analysis(9m-walk).Various kinematic parameters were recorded and analyzed such as thoracic angle(TA),lumbar angle(LA)and sagittal vertical axis(SVA).The kinetic parameters were the net reaction moments(N.m/kg)at the thoracolumbar and lumbosacral junctions.RESULTS TA and LA curves were not statistically correlated to the age(respectively,P=0.32 and P=0.41).SVA increased significantly with age(P<0.001).Moments in sagittal plane at the lumbosacral junction were statistically correlated to the age(P=0.003),underlining the fact that sagittal mechanical constraints at the lumbosacral junction increase with age.Moments in transversal plane at the thoracolumbar and lumbosacral junctions were statistically correlated to the age(P=0.0002and P=0.0006),revealing that transversal mechanical constraints decrease with age.CONCLUSION The kinetic analysis showed that during growth,a decrease of torsional constraint occurs while an increase of sagittal constraint is observed.These changes in spine biomechanics are related to the crucial role of the trunk for bipedalism acquisition,allowing stabilization despite lower limbs immaturity.With the acquisition of mature gait,the spine will mainly undergo constraints in the sagittal plane.

One and Two Photon Excitation of Radiofrequency Trapped Ca

Radiofrequency （rf） trapped ions are versatile candidates for a large panel of applications ranging from quantum information to the creation of cold molecules. Sample size can range from a single to 10^6 ions, and the internal and external energy states of the atoms can be controlled with high precision. In the experiment, we focus on different protocols related to frequency metrology using rf trapped Ca.

A Review on Tectonic Record of Strain Buildup and Stress Release across the Andean Forearc along the Gulf of Guayaquil-Tumbes Basin (GGTB) near Ecuador-Peru Border

Gravimetric and geologic data show that the reactivation of the Neogene Interandean depression and/or the ~75 - 65 Ma ophiolite suture into the modern dynamic of the Andes controlled the Gulf of Guayaquil Tumbes basin (GGTB) location and evolution during the past 1.8 - 1.6 Myr at least. Depending on whether the remobilization occurred along the interandean depression or the ophiolite suture, the GGTB evolved trough pure or simple shear mechanisms, respectively. Because the GGTB exhibits an along strike tectonic asymmetry associated with a pervasive seismic gap, the simple shear solution is more likely. Tectonic inversion occurred along a mid-crust detachment (the Mid-Crust detachment hereafter) matching the ophiolite suture that accommodates the North Andean Block (NAB) northward drift. The so-called Decoupling Strip located at the shelf slope break accommodated the tensional stress rotation from N-S along the shelf area i.e. NAB-drift induced to E-W along the continental margin i.e. subduction-erosion-induced. The landward dipping Woollard detachment system located at the Upper-Lower slope boundary connects the subduction channel at depth, allowing the Upper slope to evolve independently from the Lower slope wedge. The long-term recurrence interval between earthquakes, the strong interplate coupling, and the aseismic creeping deformation acting along the main low-angle detachments i.e. the Woollard and the Mid-Crust detachments may account for the pervasive seismic gap at the GGTB area. Because the subduction channel exhibits no record of significant seismic activity, no evidence exists to establish a link between the GGTB sustained subsidence and a basin-centered asperity. Because the GGTB is a promising site of hydrocarbon resources, to understand processes at the origin of this escape-induced forearc basin has a major economic interest.

Kinetics and mechanism of thymine degradation by TiO_2 photocatalysis

The advanced oxidation processes were examined toward the degradation of thymine （CsH6N202）, a type of nucleic acid from the pyrimidine family. As observed, the photodegradation of thymine over TiO2 photocatalyst was rapid and significant in aqueous solution under UV irradiation. Different parameters were studied, including the adsorption of thymine onto TiO2 photocatalyst, the kinetics of degradation, and the effect of pH on the photocatalytic properties of thymine degradation. Additionally, the mineralization of the products obtained upon thymine photodegradation was studied. The disappearance and mineralization rates of thymine during the photocatalytic process were also compared and discussed. The mineralization of nitrogen was also investigated, and the identification of the intermediate products was established. Finally, electronic density calculations were used to propose possible chemical pathways for the photodegradation of thymine over TiO2 photocatalyst under UV irradiation.

Refined Agent Model Using Shape-Based Grained Structure: Application to Membrane Molecules

Multi-agent model is well-known to suit design of complex systems. This paradigm allows describing autonomous entities to interact together directly or through their environment. It is specially adapted to design 3D simulations taking into account spatial constraints on agents. In this work, we have designed a multi-agent model which adds a feature to the classical representation of agent: a body, encapsulating a physical model of the agent. We have applied this model to lipids and proteins belonging to the inner mitochondrial membrane, a biological membrane. Information provided by atomic structures is available through international databases and has been used to design a shape-based grain model for the agent body. We selected a model with three grains per molecule in which each grain is characterized by a type determining how they interact together and consequently the agent behaviors. Lipids and two kinds of protein structures have been described within this model allowing us to simulate their organization in membranes.

法国阿尔卑斯山西部大型S6chilienne滑坡的深层地球

在大型S6chilienne滑坡开展了地球物理成像活动，包括4条长度950m的电剖面和4条长度470m的地震剖面，目的在于限制受影响区的深度与体积。与未受扰动的地面相比，滑动区域展现了较低速度和较高电阻率值。对比现有大地测量数据、地形数据和地质数据（调查通道与钻孔）表明，这些地球物理参数的变化主要由密集断裂以及滑动物质范围内空气填充孔隙渐进发育引起。在最不稳定区内发现的滑动物质最大厚度为150m至200m。局部地区显示近垂直极低电阻率异常，这与由粘土质物质填充的碎裂区有关。通过应用Wyllie实验定律，从地震层析成像剖面导出岩体孔隙度图像。经调查，从不稳定区顶部至底部的孔隙率在30％和4％之间，这表明了深水位的影响。假定探测基岩的孔隙率界限为3．7％，那么，Sechilienne滑坡的总体积估计约为60×10×10^6m^3，该值比原来的估计值（20×106to100×10^6m^3）更为精确。

Nanoscale Stiffness Distribution in Bone Metastasis

Nanomechanical heterogeneity is expected to have an effect on elasticity, injury and bone remodelling. In normal bone, we have two types of cells (osteoclasts and osteoblasts) working together to maintain existing bone. Bone cancers can produce factors that make the osteoclasts work harder. This means that more bone is destroyed than rebuilt, and leads to weakening of the affected bone. We report here the first demonstration of the nanoscale stiffness distribution in bone metastases before and after treatment of animals with the bisphosphonate Risedronate, a drug which is currently used for the treatment of bone metastases in patients with advanced cancers. The strategy used here is applicable to a wide class of biological tissues and may serve as a new reflection for biologically inspired scaffolds technologies.

Investigations on MBSE modelling and dynamic performance assessment of an electrical trimmable horizontal stabilizer actuator

With the development of power-by-wire technology for more electric aircraft,the electromechanical actuator(EMA)has the advantages to replace the conventional hydraulic servo actuator in some aerospace flight controls.Conventional hydraulically powered trimmable horizontal stabilizer actuation(THSA)system is nowadays developed to be electrically supplied.Given their safety-criticality,no-back mechanism and redundant load paths are utilized to meet the flight control requirements.However,rare literatures have introduced these functions and addressed the virtual prototyping activities from system-level point of view.This paper proposed such a model of a THSA system with dual electric power sources and fault-tolerant mechanical load paths.The nonlinear effects of components are considered with realism,and system-level simulation test is conducted to support the model-based system engineering(MBSE)approach.The models are developed with a power view instead of a pure signal view.Focusing on the friction effect and compliance effect with backlash or preload,some improved and novel approaches are adopted for these crucial components and validated via experimental results.Meanwhile,the implemented systemlevel model enables injection of crucial faults.Finally,the simulation of the proposed model shows that it is an efficient resource to investigate the actuator’s dynamic performance,to virtually prove that the actuator meets the fail/safe constraint,and to demonstrate the soundness of the fault monitoring functions.

区域性系统调查方法在典型遗址研究中的应用——以吉林大安汉书遗址为例

2012~2014年,后套木嘎遗址考古队连续三年在大安市新荒泡与月亮泡周边作了区域性系统调查[1]。'区域系统调查(Systematic Regional Survey),又称作全覆盖式调查(Full-Coverage Survey),是以聚落形态为目的的考古调查方法。'[2]2014年度在该区域调查时途经汉书遗址,并运用区域性系统调查方法对该遗址进行了调查、采集和记录。本次调查将全部队员分为四组(J、K、I、L组)。

Modelling and simulation of flight control electromechanical actuators with special focus on model architecting, multidisciplinary effects and power flows

In the aerospace field, electromechanical actuators are increasingly being implemented in place of conventional hydraulic actuators. For safety-critical embedded actuation applications like flight controls, the use of electromechanical actuators introduces specific issues related to thermal balance, reflected inertia, parasitic motion due to compliance and response to failure. Unfortunately, the physical effects governing the actuator behaviour are multidisciplinary, coupled and nonlinear. Although numerous multi-domain and system-level simulation packages are now available on the market, these effects are rarely addressed as a whole because of a lack of scientific approaches for model architecting, multi-purpose incremental modelling and judicious model implementation. In this publication, virtual prototyping of electromechanical actuators is addressed using the Bond-Graph formalism. New approaches are proposed to enable incremental modelling,thermal balance analysis, response to free-run or jamming faults, impact of compliance on parasitic motion, and influence of temperature. A special focus is placed on friction and compliance of the mechanical transmission with fault injection and temperature dependence. Aileron actuation is used to highlight the proposals for control design, energy consumption and thermal analysis, power network pollution analysis and fault response.

Multi-level virtual prototyping of electromechanical actuation system for more electric aircraft

Electromechanical actuators（EMAs） are becoming increasingly attractive in the field of more electric aircraft because of their outstanding benefits, which include reduced fuel burn and maintenance cost, enhanced system flexibility, and improved management of fault detection and isolation. However, electromechanical actuation raises specific issues when being used for safetycritical aerospace applications like flight controls： huge reflected inertia to load, jamming-type failure, and increase of backlash with service due to wear and local dissipation of heat losses for thermal balance. This study proposes an incremental approach for virtual prototyping of EMAs. It is driven by a model-based system engineering process in order to enable simulation-aided design.Best practices supported by Bond graph formalism are suggested to develop a model＇s structure efficiently and to make the model ready for use（or extension） by addressing the above mentioned issues. Physical effects are progressively introduced, and the realism of lumped-parameter models is increased step-by-step. In particular, multi-level component models are architected to ensure continuity between engineering activities. The models are implemented in the AMESim simulation environment, and simulation responses are given to illustrate how they can be used for preliminary sizing, control design, thermal balance verification, and faults to failure analysis. The proposed best practices intend to provide engineers with fast, reusable, and efficient means to assess performance virtually and enhance maturity, performance, and robustness.

Review on signal-by-wire and power-by-wire actuation for more electric aircraft

The huge and rapid progress in electric drives offers new opportunities to improve the performances of aircraft at all levels：fuel burn,environmental footprint,safety,integration and production,serviceability,and maintainability.Actuation for safety-critical applications like flight-controls,landing gears,and even engines is one of the major consumers of non-propulsive power.Conventional actuation with centralized hydraulic power generation and distribution and control of power by throttling has been well established for decades,but offers a limited potential of evolution.In this context,electric drives become more and more attractive to remove the natural drawbacks of conventional actuation and to offer new opportunities for improving performance.This paper takes the stock,at both the signal and power levels,of the evolution of actuation for safety-critical applications in aerospace.It focuses on the recent advances and the remaining challenges to be taken toward full electrical actuation for commercial and military aircraft,helicopters,and launchers.It logically starts by emphasizing the specificity of safety-critical actuation for aerospace.The following section addresses in details the evolution of aerospace actuation from mechanically-signaled and hydraulically-supplied to all electric,with special emphasis on research and development programs and on solutions entered into service.Finally,the last section reviews the challenges to be taken to generalize the use of all-electric actuators for future aircraft programs.

Evolution, accessibility and dynamics of road networks in China from 1600 BC to 1900 AD

Before the emergence of modern modes of transport, the traditional road infra structure was the major historical means of carrying out nationwide socioeconomic exchange However, the history of transport infrastructure has received little attention from researchers. Given this background, the work reported here examined the longterm development of transport networks in China. The national road network was selected for study and the 3500 years from 1600 BC to 1900 AD was chosen as the study period. Indicators were designed for the maturity level of road networks and an accessibility model was developed for the paths of the shortest distance. The evolution of the road network in China since the Shang Dynasty （1600 BC） was described and its major features were summarized to reveal longterm regu larities. The maturity level of the road network and its accessibility was assessed and regions with good and poor networks were identified. The relationship between China＇s natural, social and economic systems and the road network were discussed. Our analysis shows that the road network in China has a number of longterm regularities. The continuously expanding road network follows a path of inland expansion especially towards the border areas. How ever, its coverage and accessibility are characterized by a coreperipheral configuration, which has close relationships with, not only the natural conditions, but also national defense and warfare. The centralization of national power, national land governance, postal transport, the transport of specialized cargos, and international trade are also related to the develop ment of the road network. This research draws attention to the evolving regularities of trans port networks.

Best practices for model-based and simulation-aided engineering of power transmission and motion control systems

This paper deals with the modelling and simulation of aircraft systems, in particular for power transmission and control. It is intended to review, propose and disseminate best practices for making model-based/simulation-aided engineering more efficient at any phase of the system life cycle. The proposals are aimed at creating value, not only by increasing the performance of the product under study but also by shortening the time to market, capitalizing knowledge, mitigating risks and facilitating concurrent engineering. The needs associated with the engineering activities are firstly identified to define a set of requirements for the models. Then, these requirements are used to drive the considerations leading to model development, focusing in particular on the process,modelled physical effects, modelling level, model architecting and concurrent engineering. The third part deals with the model implementation, giving special consideration to the different types of models, causalities, parameterization, implementation and verification. Each part is illustrated by examples related to safety critical actuators.

Palcernuine, the first [5/6/6/6]-cernuane-type alkaloid from Palhinhaea cernua f.sikkimensis

One novel（named palcernuine, 1） and five known cernuane-type（2–6） alkaloids were isolated from the whole plant of Palhinhaea cernua f. sikkimensis. The structure of 1, possessing an unprecedented [5/6/6/6]-tetracyclic ring system containing two nitrogen atoms, was established on the basis of spectroscopic methods, and its absolute configuration was determined by comparison of the experimental and calculated electronic circular dichroism（ECD） spectra. A plausible biosynthetic pathway to 1 is proposed.

Joint Multi-modal Parcellation of the Human Striatum:Functions and Clinical Relevance

The human striatum is essential for both lowand high-level functions and has been implicated in the pathophysiology of various prevalent disorders,including Parkinson's disease(PD)and schizophrenia(SCZ).It is known to consist of structurally and functionally divergent subdivisions.However,previous parcellations are based on a single neuroimaging modality,leaving the extent of the multi-modal organization of the striatum unknown.Here,we investigated the organization of the striatum across three modalities—resting-state functional connectivity,probabilistic diffusion tractography,and structural covariance—to provide a holistic convergent view of its structure and function.We found convergent clusters in the dorsal,dorsolateral,rostral,ventral,and caudal striatum.Functional characterization revealed the anterior striatum to be mainly associated with cognitive and emotional functions,while the caudal striatum was related to action execution.Interestingly,significant structural atrophy in the rostral and ventral striatum was common to both PD and SCZ,but atrophy in the dorsolateral striatum was specifically attributable to PD.Our study revealed a cross-modal convergent organization of the striatum,representing a fundamental topographical model that can be useful for investigating structural and functional variability in aging and in clinical conditions.

Transition metal-templated synthesis of catenanes and rotaxanes

Among the various methods nowadays used to make catenanes and rotaxanes,the metal template synthesis occupies a place of choice,because of its versatility.This contribution shows that,thanks to the richness of their chemistry,metal templates can fulfil multiple functions for the construction of these topologically-interesting molecules,from the entwining or threading of their precursors to the simultaneous catalysis of the interlocking reaction.