Critical State Sedimentation Line of Soft Marine Clays

The compression behavior responsible for unity sensitivity is very valuable in quantitative assessment of the effects of soil structure on the compression behavior of soft marine sediments. However, the quantitative assessment of such effects is not possible because of unavailability of the formula for the compression curve of marine sediments responsible for unit sensitivity. In this study, the relationship between the remolded state and the conventional critical state line is presented in the deviator stress versus mean effective stress plot. The analysis indicates that the remolded state is on the conventional critical state line obtained at a relatively small strain. Thus, a unique critical state sedimentation line for marine sediments of unit sensitivity is proposed. The comparison between the critical state sedimentation line proposed in this study and the existing normalized consolidation curves obtained from conventional oedometer tests on remolded soils or reconstituted soils explains well the

Recent Industrial Developments of Marine Composites Limit States and Design Approaches on Strength

To further exploit the potential of marine composites applications in building ship hulls,offshore structures,and marine equipment and components,design approaches should be improved,facing the challenge of a more comprehensive and explicit assessment of appropriately defined limit states.The structure ultimate/limit conditions shall be verified in principle within the whole structural domain and throughout the ship service life.What above calls for extended and reliable materials characterization on the one hand and for accurate and wide-ranging procedures in structural analyses.This paper presents an overview of recent industrial developments of marine composites limit states assessments and design approaches,as available in open literature,focusing on pleasure crafts and yachts as well as navy ships and thus showing a starting point to fill the gap in this respect.After a general introduction about composites characterization techniques,current design practice and rule requirements are briefly summarized.Both inter-ply and intra-ply failure modes and corresponding limit states are then presented along with recently proposed assessment approaches.Three-dimensional aspects in failure modes and manufacturing methods have been identified as the main factors influencing marine composite robustness.Literature review highlighted also fire resistance and hybrid joining techniques as significant issues in the use of marine composites.

An assessment of “fishing down marine food webs” in coastal states during 1950–2010

Mean trophic level of fishery landings（MTL） is one of the most widely used biodiversity indicators to assess the impacts of fishing. Based on the landing data compiled by Food and Agriculture Organization combined with trophic information of relevant species in Fish Base, we evaluated the status of marine fisheries from 1950 to 2010 for different coastal states in Pacific, Atlantic and Indian Oceans. We found that the phenomenon of ＂fishing down marine food webs＂ occurred in 43 states. Specifically, 27 states belonged to ＂fishing-through＂ pattern, and 16 states resulted from ＂fishing-down＂ scenario. The sign of recovery in MTL was common in the Pacific, Atlantic and Indian Oceans（occurred in 20 states）, but was generally accompanied by significantly decreased catches of traditional low trophic level species. In particular, 11 states showed significant declining catches of lower trophic levels. The MTL-based assessment of ＂fishing down marine food webs＂ needs to be interpreted cautiously.

Carrying Capacity of Marine Region in Liaoning Province

Carrying capacity is one of important studies on coordinating development of population,resources,and environment.At present,the researches on it mainly concentrate on the carrying capacity for population and economy,such as the water resources carrying capacity,the land resources carrying capacity,the environment carrying capacity,etc.Based on the related theories and methods,this paper creatively proposed the concept and meaning of carrying capacity of marine region,and formed the appraisal system.According to the developing situation of marine economy of Liaoning Province in recent years,and by employing the method of the state space,this paper also measured the carrying capacity and carrying state of marine region and discussed the sustainable problems of marine economy of Liaoning.The research results show that the carrying state of marine region of Liaoning is in the state of overloading at present,but taking a favorable turn.

A Note on Soil Structure Resistance of Natural Marine Deposits

It has been well documented that natural normally-consolidated marine soils are generally subjected to the effects of soil structure. The interpretation of the resistance of soil structure is an important issue in the theory study and engineering practice of ocean engineering and geotechnical engineering. It is traditionally considered that the resistance of soil structure gradually disappears with increasing stress level when the applied stress is beyond the consolidation yield stress. In this study, however, it is found that this traditional interpretation of the resistance of soil structure can not explain the strength behavior of natural marine deposits with a normally-consolidated stress history. A new interpretation of the resistance of soil structure is proposed based on the strength behavior. In the preyield state, the undrained strength of natural marine deposits is composed of two components: one developed by the applied stress and the other developed by the resistance of soil structure. When the applied stress is beyond the consolidation yield stress, the strength behavior is independent of the resistance of soil structure.

Measurement and Evolution of High-quality Development Level of Marine Fishery in China

High-quality development of marine fisheries provides an important advantage for China to build itself into a maritime power and implement the Blue Granary Plan effectively.Based on the concepts of‘new development’,‘food security’,and the six dimensions of‘openness,innovation,coordination,green,sharing,and security’,in this study,we established an evaluation index system for the high-quality development of China’s marine fishery sector.We applied the entropy method to evaluate the high-quality development level of China’s marine fishery sector from 2000 to 2016 and explored its spatial and temporal evolution rules.Our results indicated that:1)from 2000 to 2016,China’s marine fishery sector was in the primary stage of high-quality development;2)spatially,the highquality development of marine fisheries showed an upward trend in all provinces,autonomous regions,and municipalities in the country(not including Hong Kong,Macao and Taiwan of China),and with time,the distribution pattern changed from single to multi-polarization;3)temporally,the development level of high-quality marine fisheries fluctuated during the study period.From 2000 to 2010,the growth rate in openness was relatively slow,but after 2010,it increased rapidly.Notably,innovation is the driving force for high-quality development.The green and security factors provide a solid guarantee for high-quality development.In the high-quality development of a region,economic development is better coordinated,and the distribution of benefits is more inclusive.This study provides a theoretical basis to formulate effective marine fishery policies for the high-quality development of the marine fishery sector in China.Exploring the high-quality development and evolution process of marine fishery is conducive to promoting the sustainable development of marine fishery industry,ensuring marine fishery food security,and alleviating global food crisis.

Calculation of earth pressure based on disturbed state concept theory

The theoretical formulations of Coulomb and Rankine still remain as the fundamental approaches to the analysis of most gravity-type retaining wall,with the assumption that sufficient lateral yield will occur to mobilize fully limited conditions behind the wall.The effects of the magnitude of wall movements and different wall-movement modes are not taken into consideration.The disturbance of backfill is considered to be related to the wall movement under translation mode.On the basis of disturbed state concept(DSC),a general disturbance function was proposed which ranged from-1 to 1.The disturbance variables could be determined from the measured wall movements.A novel approach that related to disturbed degree and the mobilized internal frictional angle of the backfill was also derived.A calculation method benefited from Rankine's theory and the proposed approach was established to predict the magnitude and distribution of earth pressure from the cohesionless backfill under translation mode.The predicted results,including the magnitude and distribution of earth pressure,show good agreement with those of the model test and the finite element method.In addition,the disturbance parameter b was also discussed.

Mesoscopic analysis of the utilization of hardening model for a description of softening behavior based on disturbed state concept theory

Mesoscopic characteristics of a clayey soil specimen subjected to macroscopic loading are examined using a medi- cal-use computerized tomography (CT) instrument. Disturbed state concept (DSC) theory is based on the utilization of the hard- ening model. DSC indirectly describes material behavior by claiming that the actual response of the material is expressed in terms of the relative intact (RI) response and the fully adjusted (FA) response. The occurrence of mesoscopic structural changes of material has similarities with the occurrence of a macroscopic response of the material under loadings. In general, the relative changing value of a softening material is three to five times more than that of a hardening material. Whether special zones exist or not in a specimen cross section does not affect the following conclusion: hardening material and softening material show me- chanical differences with CT statistical indices values prominently changing, and the change is related to the superposing of a disturbance factor. A new disturbance factor evolution function is proposed. Thus, mesoscopic statistical indices are introduced to describe macroscopic behavior through the new evolution function. An application of the new evolution function proves the effectiveness of the amalgamation of a macroscopic and a mesoscopic experimental phenomenon measurement methods.

Disturbed state concept as unified constitutive modeling approach

A unified constitutive modeling approach is highly desirable to characterize a wide range of engineeringmaterials subjected simultaneously to the effect of a number of factors such as elastic, plastic and creepdeformations, stress path, volume change, microcracking leading to fracture, failure and softening,stiffening, and mechanical and environmental forces. There are hardly available such unified models. Thedisturbed state concept （DSC） is considered to be a unified approach and is able to provide materialcharacterization for almost all of the above factors. This paper presents a description of the DSC, andstatements for determination of parameters based on triaxial, multiaxial and interface tests. Statementsof DSC and validation at the specimen level and at the boundary value problem levels are also presented.An extensive list of publications by the author and others is provided at the end. The DSC is considered tobe a unique and versatile procedure for modeling behaviors of engineering materials and interfaces. 2016 Institute of Rock and Soil Mechanics, Chinese Academy of Sciences. Production and hosting byElsevier B.V. This is an open access article under the CC BY-NC-ND license

Dynamic Positioning System Design for A Marine Vessel with Unknown Dynamics Subject to External Disturbances Including Wave Effect

In this paper, a new control system is proposed for dynamic positioning(DP) of marine vessels with unknown dynamics and subject to external disturbances. The control system is composed of a substructure for wave filtering and state estimation together with a nonlinear PD-type controller. For wave filtering and state estimation, a cascade combination of a modified notch filter and an estimation stage is considered. In estimation stage, a modified extended-state observer(ESO) is proposed to estimate vessel velocities and unknown dynamics. The main advantage of the proposed method is its robustness to model uncertainties and external disturbances and it does not require prior knowledge of vessel model parameters. Besides, the stability of the cascade structure is analyzed and input to state stability(ISS) is guaranteed. Later on, a nonlinear PD-type controller with feedforward of filtered estimated dynamics is utilized. Detailed stability analyses are presented for the closed-loop DP control system and global uniform ultimate boundedness is proved using large scale systems method. Simulations are conducted to evaluate the performance of the proposed method for wave filtering and state estimation and comparisons are made with two conventional methods in terms of estimation accuracy and the presence of uncertainties. Besides, comparisons are made in closed-loop control system to demonstrate the performance of the proposed method compared with conventional methods. The proposed control system results in better performance in the presence of uncertainties,external disturbance and even in transients when the vessel is subjected to sudden changes in environmental disturbances.

From Early States to Modem States in China： The Changing Concept and Connotation of ＂State＂

The substantive characteristics of the connotation of ＂State＂ include two parts： （I） the relatively perpetual and impersonalized political system; （II） the ductility of organization forms within the space and politics. And the later part is the absolute attribute of this connotation while the former part tends to show with different forms. Therefore, it is more suitable for the former one to be the objective for study on the evolution process of the connotation of ＂State＂ at different stages. Based on this understanding, the author discusses the specific political system at different stages and the relatively perpetual and impersonalized methods for the realization of the system, then tries to define the connotation of the early state, ancient state and modem state in Chinese history.

Li Dazhao’s Conception of Modern State Before the New Culture Movement

Based on the following two points that one is the social disorder resulted from the“republic”since the Revolution of 1911 and the other is constant reflection on the recognition of the political values of western political parties,Li Dazhao places his hope on awakening and strength of the people to deal with the gap between republican political ideal and social reality of the Republic of China finally.This kind of emphasis and expectation on the power of people makes up a key factor assisting Li Dazhao’s early conversion to Marxism.

国际海洋经济卫星账户实践及对中国启示

近年来,世界各国对海洋经济发展的重视程度日益提高。海洋经济卫星账户致力于提供与国民经济一致可比的统计数据,逐渐成为衡量海洋经济可持续发展的有力工具。通过回顾国际海洋经济统计的最新进展,重点介绍了葡萄牙和美国海洋经济卫星账户应用实践,最后针对我国海洋经济统计核算工作现状与问题提出了相关建议,以期为海洋经济监测评估与政策制定提供参考。

概念:存在和存在者状态——阿多诺对概念另类分析及其启示

在哲学研究中,传统的概念分析被束缚在实证科学的框架中,然而对阿多诺来说,哲学使用的概念与实证科学是不同的,哲学概念不是直接与经验要素结合在一起的,哲学概念必须抽象化,但是这个抽象化的概念又必须与经验的东西联系起来。这种联系是在概念的经验运用中发生的,而这种经验运用又必须在思想的自我反思中进行。概念的这种经验的运用使概念获得了存在者状态。而海德格尔在这种存在者状态之外设想了一种存在,好像存在具有原始的命名力量,它能够把概念和概念所涉及的东西直接结合起来。其实存在是一种普遍的中介,它不能脱离被中介者而存在。唯物主义在使用概念的时候必须在辩证法的意义上经验地使用概念。

数据态档案管理模式概念、特征与挑战

在档案资源对象发展演化的过程中,数据态档案作为新型资源对象,具有信号和语义双重离散的本质特征。因此,有必要对已有档案管理理念和实践进行重塑,建立能够解除语义离散带来的高阶逻辑依赖的数据态档案管理模式。本文在档案资源连续空间演化图景的指导下,明确数据态档案管理模式的概念及功能定位,阐明其区别于其他形态档案资源管理模式的特征,并对模式构建所面临的主要挑战进行分析。研究认为数据态档案管理模式以体系性、连续性、可理解性和专业性为主要特征,在空间管控、证用价值维系、管理机制协同与技术能力建设等方面面临挑战。

美国“犯罪”观念对英国普通法的传承与超越

犯罪观念不仅是刑法学科的问题,也是国家历史的一个组成部分。英美法系以判例法为主,重视经验和实用,因此两国至今未能颁布一部成文且统一的刑法典而对“犯罪”作出一致表述。美国作为英国的前殖民附属地,自然继承了普通法上的“犯罪”观念,这在犯罪的分类、构成要件和影响因素等方面均有所体现。而美国自独立战争胜利后制定的联邦宪法,助力其在刑法领域的改革与发展。从历史的角度来分析社会现象之一的犯罪,有助于我们把握美国各历史阶段下犯罪与宗教、道德、政权、经济之间的互动关系,探究美国独立后区别于英国普通法下犯罪观念的成果。

基于Bobath理念下的康复训练改善脑卒中偏瘫患者步态的临床研究

目的探究基于Bobath理念下的康复训练在脑卒中偏瘫患者中的应用。方法选取惠州市中心人民医院2021年1月至2023年4月104例脑卒中偏瘫患者作为研究对象,依照康复方式分为常规康复组和Bobath技术组。两组均行低频重复经颅磁刺激。常规康复组给予常规康复训练,Bobath技术组给予基于Bobath理念下的康复训练,对比两组步态状态、运动能力、平衡能力。结果治疗12周后,Bobath技术组10 m最快步行速度(MWS)(0.73±0.17)m/min、步长(42.21±4.07)cm及Fugl-Meyer上肢运动功能评定量表(FMA-UE)(53.24±4.13)分、Fugl-Meyer下肢运动功能评定量表(FMA-LE)(28.32±2.95)分、Berg平衡量表(BBS)(49.16±3.24)分、脑卒中姿势评定量表(PASS)(25.81±3.06)分高于常规康复组(0.61±0.12)m/min、(37.76±3.82)cm、(45.93±3.51)分、(24.17±2.72)分、(40.25±3.13)分、(21.24±1.82)分;威斯康星步态量表(WGS)(15.83±1.43)分低于常规康复组(24.21±1.75)分(P<0.05)。结论基于Bobath理念下的康复训练可调控脑卒中偏瘫患者平衡能力,改善其步态状态,调节运动能力。

船舶自动识别系统(AIS)数据在海洋渔业中研究应用现状

在全球海洋主要经济渔业资源衰退的背景下,如何保护和可持续开发利用海洋渔业资源受到全球各国、地区和组织高度重视,一直是研究热点。受传统海洋渔业数据的制约,一直难以全面了解远洋渔船的捕捞足迹,因此,无法对其实行有效监控和管理。船舶自动识别系统(automatic identification system,AIS)提供的全球远洋渔船轨迹数据可以用于量化分析从单艘到全球渔船行为,挖掘的历史捕捞强度空间信息可为海洋捕捞活动的监测管理和生态压力评估提供良好的可替代数据来源,成为近年海洋信息和海洋渔业研究的新热点。为促进AIS数据在我国海洋渔业中的研究应用,对AIS近年的研究内容和应用现状进行总结,指出AIS数据目前研究的不足和未来潜在的研究方法,以期为AIS在海洋渔业中的研究和应用提供参考。

基于扰动状态概念的砂土-混凝土桩接触面荷载传递模型研究

基于扰动状态概念理论,考虑砂土密实度对扰动函数的影响,建立混凝土桩-砂土接触面荷载传递模型。用混凝土板表征桩侧粗糙度效应,采用大型直剪仪开展不同密实度的砂土-混凝土桩接触面力学行为的试验模拟,研究砂土密实度对混凝土桩-砂土接触面的力学特性的影响规律,分析接触面模型初始剪切系数、模型扰动参数(A和Z)对桩-砂土接触面荷载传递模型的作用机制。研究结果表明:1)混凝土桩-砂土接触面易呈现应变软化,在低法向应力条件下,混凝土桩-密砂接触面的应变软化程度最大。2)模型扰动参数Z在数值上近似等于孔隙比。模型扰动参数A越大,砂土与混凝土桩接触面的软化显著程度越大。参数A随着密实度增大而增大。随着法向应力增大,密砂的扰动参数A呈近似线性衰减,松砂和中密砂的扰动参数A近似呈双折线衰减。3)初始剪切系数k_s随着法向应力增大而增大,密实度越大,增速越快。4)基于扰动状态概念的桩-砂土接触面荷载传递模型可靠、参数的物理意义明确且易确定,能很好地表征桩-砂土接触面的应变软化及硬化等力学特征。

双星跟飞测高卫星在轨初步验证

卫星测高反演重力场的常规做法是利用海面高差求解垂线偏差,进一步计算海洋重力异常和海洋大地水准面高等信息。显然,提高海面高差的测量精度可以直接提升海洋重力场的反演精度。本文给出了双星跟飞卫星测高原理,通过轨道设计使双星星下点跨轨间距(即分辨率)在1′左右,双星同时测量沿其轨道的海面高差及跨轨的星间海面高差,此时轨道径向误差表现为星间或单星历元间的相对轨道径向误差,而与大气传播和地球物理效应等有关的改正项,对于地面轨间距只有1′的双星近似相等,其在海面高差中几无体现,因此海面高差的精度相比于传统的单星测量将有显著提高。利用测高A/B双星的实际观测数据,初步验证了相对轨道径向误差和海面高差中的8项改正的差值误差。结果表明,对于定标阶段约25 km的星下点间距,干对流层、湿对流层、电离层、固体潮、极潮和逆大气压等改正项的差值误差均在5 mm量级;海潮改正差值、海况偏差差值中分别有约1 cm和2 cm的残留误差;对于业务轨道约2 km的星下点间距,相对轨道径向误差约为3 mm,除了海况偏差差值有约0.52 cm的残留误差,其他改正项的差值误差均小于0.05 cm,可完全忽略不计。