New Rural Community Construction or Retention Development:A Comparative Analysis of Rural Settlement Transition Mechanism in Plain Agriculture Area of China Based on Actor Network Theory

It is an important way to realize rural revitalization and sustainable development to guide rural settlement transition(RST)in an appropriate way.This paper uses actor network theory(ANT)to construct a theoretical framework for the study of RST.Taking two typical villages with different transition paths in rural areas of North China Plain as examples,this paper reveals the mechanism of RST and makes a comparative analysis.The results show that:1)after identifying problems and obligatory passage point,key actors recruit heterogeneous actors into the actor network by entrusting them with common interests,and realize RST under the system operation.2)Rural settlements under different transition paths have similarities in the problems to be solved,collective actions and policy factors,but there are differences in the transition process,mechanism and effect.The actor network and mechanism of RST through the path of new rural community construction are more complex and the transition effect is more thorough.In contrast,the degree of RST of retention development path is limited if there is no resource and location advantage.3)Based on the applicable conditions of different paths,this paper designs a logical framework of‘Situation-Structure-Behavior-Result’to scientifically guide the identification of RST paths under the background of rural revitalization.

Coupling Mechanism of Rural Settlements and Mountain Disasters in the Upper Reaches of Min River

Human settlements are the place where human beings live,among which the rural settlements can be regarded as a reflection of human-land relationship in mountain areas because their vertical distribution is greatly influenced by the specific geographical environment and ecological conditions of mountains.Based on field investigation,this paper uses physical,geographical,and ecological theories to make a comprehensive study of rural settlements and mountain disasters in the upper Min River,which is an ecologically fragile area with high-frequency disasters(collapse,landslide,debris flow,etc.) and a minority inhabit district.By applying these modern scientific theories,this paper attempts to shed some light on the relationship between rural settlements and mountain disasters.Consequently,an in-depth understanding of this relationship was achieved as follows:(1) Rural settlements and mountain disasters are mainly distributed in the intercepted flows of water and soil; and both quantity and quality of arable lands in mountains are important indicators of these flows.(2) The Small Watershed Management Project is a complex system of rural settlements and mountain disasters that interacts with and constrains the ecological system.By this project,the human survival will be better guaranteed.Being fundamental for the ecological reconstruction,the coupling mechanism of rural settlements and mountain disasters is not only an engine to promote harmonious development between human and nature,but also a bridge to link them.

Failure mechanism of large-diameter shield tunnels and its effects on ground surface settlements

A new technique for the analysis of the three-dimensional collapse failure mechanism and the ground surface settlements for the large-diameter shield tunnels were presented.The technique is based on a velocity field model using more different truncated solid conical blocks to clarify the multiblock failure mechanism.Furthermore,the shape of blocks between the failure surface and the tunnel face was considered as an entire circle,and the supporting pressure was assumed as non-uniform distribution on the tunnel face and increased with the tunnel embedded depth.The ground surface settlements and failure mechanism above large-diameter shield tunnels were also investigated under different supporting pressures by the finite difference method.

Shield Excavation Analysis: Ground Settlement & Mechanical Responses in Complex Strata

This study delves into the effects of shield tunneling in complex coastal strata, focusing on how this constructionmethod impacts surface settlement, the mechanical properties of adjacent rock, and the deformation of tunnelsegments. It investigates the impact of shield construction on surface settlement, mechanical characteristics ofnearby rock, and segment deformation in complex coastal strata susceptible to construction disturbances. Utilizingthe Fuzhou Binhai express line as a case study, we developed a comprehensive numerical model using theABAQUS finite element software. The model incorporates factors such as face force, grouting pressure, jack force,and cutterhead torque. Its accuracy is validated against field monitoring data from engineering projects. Simulationswere conducted to analyze ground settlement and mechanical changes in adjacent rock and segments acrossfive soil layers. The results indicate that disturbances are most significant near the excavation zone of the shieldmachine, with a prominent settlement trough forming and stabilizing around 2.0–3.0 D from the excavation. Theexcavation face compresses the soil, inducing lateral expansion. As grouting pressure decreases, the segmentexperiences upward buoyancy. In mixed strata, softer layers witness increased cutting, intensifying disturbancesbut reducing segment floatation. These findings offer valuable insights for predicting settlements, ensuring segmentand rock safety, and optimizing tunneling parameters.

Formation Mechanism of Poor Settlements in Lanzhou City

Clarifying the formation mechanism of poor settlements is the " pathological" basis for urban regeneration and poverty governance.On the basis of scientific determination of 155 poor settlements in Lanzhou City,this paper classified their types and analyzed the characteristics of their quantity distribution and density distribution. From the perspective of spatial and social interaction,and combined the internal factors and external factors,this paper put forward the formation mechanism of poor settlements,namely,superposition of unit society collapse and physical environment degradation,interaction between differentiation of residents' income and reform of housing institution,interweaving between urban discontinuous planning and jumping construction,coupling between passive urbanization and active urbanization,and derivation of lagged economic development and unique regional culture.

Analysis of the Choice of Return Mechanism of PPP Model in Rural Human Settlement Improvement under the Rural Revitalization Strat­egy:Research Based on the Perspective of Evolutionary Game

The improvement of rural human settlement environment is a significant direction of the rural revitalization strategy.Based on the finite rational evolutionary game theory,a cooperative behavior evolutionary game model of rural human settlement environment improvement PPP model with local government,social capital and rural residents as the main game players with the reward mechanism of Government Payment and one with the reward mechanism of Viability Gap Funding are constructed.Comparing the total project revenue of two reward mechanisms,the thesis will obtain the effects of choosing the reward mechanism of rural human settlement improvement PPP.Finally,available suggestions are made to the decision of the reward mechanism of PPP project about rural human settlement environment,thus promoting the application and development of PPP in rural environmental management and to promote sustainable improvement of rural habitat improvement.

MECHANICAL ANALYSIS OF SHAFT LINING WHEN THE STRATUM SETTLEMENT RESULTING FROM WATER DRAINAGE

Based on the stratum settlement resulting from water drainage, this paper establishes the calculating method of stresses and displacements of shaft lining and stratum by using Fourier integration, obtains the calculating formulas of tangiential load which shaft lining is subjected to, and provides theoretical basis for design of shaft lining.

Kinematic analysis of shallow tunnel in layered strata considering joined effects of settlement and seepage

The purpose of this work is to predict the state of collapse in shallow tunnel in layered strata by using a new curved failure mechanism within the framework of upper bound theorem.Particular emphasis is first given to consider the effects of seepage forces and surface settlement.Furthermore,the Hoek-Brown nonlinear failure criterion is adopted to analyze the influence of different factors on the collapsing shape.Two different curve functions which describe two different rock layers are obtained by virtual work equations under the variational principle.According to the numerical results,the parameter B in Hoek-Brown failure criterion and the unit weights in different rock layers have a positive relationship with the size of collapsing block while pore pressure coefficient and the parameter A in Hoek-Brown failure criterion present a reverse tend.

Catastrophe stability analysis for shallow tunnels considering settlement

Limit analysis of the stability of geomechanical projects is one of the most difficult problems.This work investigates the influences of different parameters in NL failure strength on possible collapsing block shapes of single and twin shallow tunnels with considering the effects of surface settlement.Upper bound solutions derived by functional catastrophe theory are used for describing the distinct characteristics of falling blocks of different parts in twin tunnels.Furthermore the analytical solutions of minimum supporting pressures in shallow tunnels are obtained by the help of the variational principle.Lastly,the comparisons are made both in collapsed mechanism and stability factor with different methods.According to the numerical results in this work,the influences of different parameters on the size of collapsing block are presented in the tables and the limit supporting loads are illustrated in the form graphs that account for the surface settlement.

Limit analysis of supporting pressure in tunnels with regard to surface settlement

The proliferation of Hoek-Brown nonlinear failure criterion and upper bound theorem makes it possible to evaluate the stability of circular tunnels with an original curved collapsing mechanism. The arch effect of shallow circle tunnel is not taken into consideration so that the mechanical characteristics can be easily described. Based on the mechanism, the upper bound solution of supporting pressure of tunnels under the condition of surface settlements and overloads on the ground surface is derived. The objective function is formed from virtual work equations under the variational principle, and solutions are presented by the optimum theory. Comparisons with previous works are made. The numerical results of the present method show great agreement with those of existing ones. With regard to the surface settlement and overloads, the influence of different rock parameters on the collapsing shape is analyzed.

Tunnel face stability and ground settlement in pressurized shield tunnelling

An analysis of the stability of large-diameter circular tunnels and ground settlement during tunnelling by a pressurized shield was presented. An innovative three-dimensional translational multi-block failure mechanism was proposed to determine the face support pressure of large-shield tunnelling. Compared with the currently available mechanisms, the proposed mechanism has two unique features:(1) the supporting pressure applied to the tunnel face is assumed to have a non-uniform rather than uniform distribution, and(2) the method takes into account the entire circular excavation face instead of merely an inscribed ellipse. Based on the discrete element method, a numerical simulation of the Shanghai Yangtze River Tunnel was carried out using the Particle Flow Code in two dimensions. The immediate ground movement during excavation, as well as the behaviour of the excavation face, the shield movement, and the excavated area, was considered before modelling the excavation process.

Sediment consolidation settlement of Chengbei Sea area in the northern Huanghe River subaqueous delta,China

One of the most important factors controlling the morphology of the modem Huanghe （Yellow） River delta is consolidation settlement, which is impacted by fast deposition, high water content, and low density of seafloor sediment. Consolidation settlement of the Huanghe River subaqueous delta was studied based on field data, laboratory experiments on 12 drill holes, and the one-dimensional consolidation theory. Results show that vertical sediment characteristics varied greatly in the rapidly forming sedimentary bodies of the modem Huanghe River subaqueous delta. Sediments in the upper parts of drill holes were coarser than those in the deeper parts, and other physical and mechanical properties changed accordingly. On the basis of the one-dimensional consolidation theory and drilling depth, the final consolidation settlement of drill holes was between 0.6 m and 2.8 m, and the mean settlement of unit depth was at 1.5-3.5 cm/m. It takes about 15-20 years for the consolidation degree to reach 90% and the average sedimentation rate within the overlying 50 m strata was at 5 cm/a to 12 cm/a. This study helps to forecast the final consolidation settlement and settlement rate of the modem Huanghe River subaqueous delta, which provides key geotechnical information for marine engineers.

Analysis of Control Measures for Settlement of Differences on the Problems of Highway Subgrade Widening

The study mainly discusses the issues of the settlement of differences that occurs in the process of highway subgrade widening. Firstly, it briefly introduces the settlement of difference and its harms;then it analyzes the mechanism of settlement of differences in the process of difference widening, including four aspects: the new and old roadbeds themselves, design, construction and other links;finally, based on the above analysis of the mechanism, it discusses the corresponding control measures, mainly proposing these suggestions as followings: the use of lightweight materials, the foundation treatment, the cut slope excavation steps, and the strict control of the degree of compaction, etc. The paper is expected to provide some theoretical basis for the control measures of highway subgrade widening settlement of difference.

综掘工作面混合式风流调控下的粉尘沉降研究

煤矿掘进过程中粉尘聚集严重,目前针对综掘工作面混合式风流调控下粉尘沉降规律及优化的研究还不够深入。基于混合式风流调控系统,依托陕煤集团神木柠条塔矿业有限公司综掘工作面,分析了压风口距工作面距离、压风口右偏角度、压风口口径、抽风口距工作面距离和压抽比等混合式风流调控参数对粉尘沉降规律的影响:随着压风口距工作面距离增加,司机处和回风侧行人呼吸带截面大颗粒粉尘占比先增后减再增,小颗粒粉尘占比增加;随着压风口右偏角度增加,司机处和回风侧行人呼吸带截面大颗粒粉尘占比变化明显;随着压风口口径增加,司机处截面小颗粒粉尘占比先增后减再增,回风侧行人呼吸带截面大颗粒粉尘占比先增后减;随着抽风口距工作面距离增加,司机处截面大颗粒粉尘占比先增后减,小颗粒粉尘占比先增后减再增,回风侧行人呼吸带截面粉尘粒径分布变化不大;随着压抽比增大,司机处和回风侧行人呼吸带截面小颗粒粉尘占比减小。以上述风流调控各参数为自变量,回风侧行人呼吸带全尘平均浓度和司机处呼尘平均浓度最低为优化目标,建立了粉尘沉降优化回归模型,利用粒子群优化算法求解模型,得到最优风流调控方案:压风口距工作面距离为8.9 m,压风口右偏角度为14.8°,压风口口径为0.9 m,抽风口距工作面距离为4.3 m,压抽比为1.1。搭建了风流调控下粉尘沉降实验平台,实验结果表明:测试值与粉尘沉降优化回归模型的模拟值误差在13%以内,验证了模型的准确性;优化后粒径为71~100μm的粉尘受风流调控参数影响明显,沉降在掘进机前方;优化后回风侧行人呼吸带全尘平均浓度和司机处呼尘平均浓度分别降低了47.4%和42.4%,降尘效果明显。

广西创新国际商事争端解决机制和机构建设路径研究

通常而言,商贸活动越繁荣,对高效、公平的争端解决服务的要求就越高。高效、公平的国际商事争端解决机制除了能定分止争,还能规范国际商贸秩序并为国际商贸发展提供指引。创新国际争端解决机制是广西加快对接《区域全面经济伙伴关系协定》(RCEP)经贸新规则的重要措施之一。这既能满足争端解决的市场需求,也有助于广西进一步优化营商环境,发展相关产业,提升治理水平。比较而言,广西创新国际争端解决机制仍面临机构、人才、竞争力等方面发展不足的挑战。广西可以重点聚焦涉及东盟跨境经贸和商业领域,从集成创新政策工具释放广西各类政策红利,依靠相关优惠政策吸引争端解决人才和机构集聚,营造市场化、法治化、国际化的一流营商环境,创新发展RCEP争端解决服务机制,规划建设“争端解决服务”集中区,鼓励相关机构集聚和引导有序竞争等方面,推动国际商事争端解决机制的创新和机构发展,面向东盟和RCEP,建设具有区域特色和国际影响力的国际商事争端解决中心。

论强制调解于“一带一路”投资争端解决的适用

“一带一路”倡议实施十年间,沿线国直接投资数额显著增加、投资结构持续多元化,但也有若干项目由于投资者和当地政府矛盾而被迫中断。“一带一路”是和平之路、合作共赢之路,可以效仿国内法中的强制调解制度,通过引入程序上的强制性来扩大调解在投资者-东道国投资争端解决中的适用,发挥其比投资仲裁更为经济、灵活、有助于合作关系修复的优势。强制调解制度并不会改变调解作为ADR自愿性的本质特征,和解协议的达成仍取决于双方同意。“一带一路”投资争端解决引入强制调解制度时,应该选择适当的路径,明确适用范围,综合考虑磋商、仲裁、东道国法院诉讼等其他争端解决方式的优劣,通过程序规则衔接,着眼于一整套高效、灵活争端解决机制的构建。

乡村旅游聚落的概念模型与形成机理——基于婺源的扎根研究

旅游活动在传统乡村聚落的开展,推动形成一种新型独特聚落形态——乡村旅游聚落。本文选择婺源五个乡村旅游地为案例地,运用扎根理论的方法,构建“乡村旅游聚落”的概念模型,探索其形成机理。结果表明,乡村旅游聚落是基于原有乡村聚落,在众多内外因素的影响与作用下开展旅游活动,使聚落主体和要素等发生变化,形成既能满足居民的生产、生活等传统需要,又能满足游客、从业人员等利益相关者多重需要的一种新型聚落类型。它在空间上表现为全新的生产、生活和生态三个空间组织形态,其形成与发展经历内外因素蓄力、开发建设投入、功能产业转化、聚落空间再生产、反馈循环演化五个阶段。乡村旅游高质量发展要树立“乡村旅游聚落”系统观,编制聚落系统发展规划、建立聚落共生发展机制、加强聚落功能空间优化、注重聚落文化保护传承、重视聚落开发管理提升。

可持续迭代的村镇人居环境设计体系研究

目的为建构可持续建设与有机更新下村镇人居环境设计的基本框架,揭示其在不同发展阶段、地域特征和建设主题下村镇人居样本的应对性设计原则与理论,总结村镇设计在经济、社会、技术影响下的迭代及在地化应变,探讨未来村镇人居环境设计的前沿模式。方法基于可视化文献分析法,对可持续村镇人居环境设计进行系统的脉络梳理,并根据可持续设计的路径推演、要素解析、模式特征进行村镇人居环境设计体系的框架搭建,提出村镇人居环境设计的基本原则与适配化设计技术路线。结果构建了可持续人居建设迭代下的村镇人居环境设计体系,通过解析可持续设计的基本构成要素,分析了村镇人居环境可持续设计的动力机制,揭示了其在需求侧、供给侧和承载侧的基本特征及三者的联动关系,提出了四项村镇人居环境可持续设计的基本原则,并总结出三点分类适配化设计思路。结论以综合设计视角,探讨未来中国村镇转型下的设计思想与技术脉络,根据时代背景、在地特征、未来场景,采取动态应变与适配的原则,提出可持续设计模式、方法与路径,为设计学相关研究者、决策者和执业人员提供理论梳理和实践指导。

预制拼装综合管廊承插式接头扭转力学性能

为研究节段预制拼装综合管廊承插式接头扭转力学性能,利用ABAQUS有限元软件建立预制拼装管廊节段与土体纵向三维模型,对管廊正向扭转与反向扭转进行模拟,分析管廊扭转承插式接头应力分布规律,得到管廊承插式接头扭矩随横向差异沉降变化规律及管廊横向极限差异沉降量。研究结果表明:管廊节段正向扭转与反向扭转沉降量相同时,承插式接头应力、最大主应力与切应力分布规律基本相同。管廊扭转接头插口端侧壁应力较大,接头顶底板中间与腋角处应力较小,接头最大主应力集中在承口端侧壁距顶板外侧1 m处与插口端顶底板,接头切应力在顶底板中间与侧壁中间最小,向两侧逐渐增大至腋角处切应力最大。管廊承插式接头横向极限差异沉降为1.2 mm,管廊插口端极限扭矩与采用箱型截面计算的结果相差不大,工程实际中可采用箱型截面对管廊插口端抗扭设计。研究结果为预制拼装管廊安全运营提供科学依据。

以创造精神抓住契机推动世界贸易组织上诉机制的改革

习近平总书记在2023年9月27日中共中央政治局有关世界贸易组织规则与世界贸易组织改革的集体学习会上强调,“参与世界贸易组织改革,要坚定维护以世界贸易组织为核心的多边贸易体制权威性和有效性,积极推动恢复世界贸易组织争端解决机制正常运转”。在WTO上诉机制已经陷入危机、多边贸易体制本身相关性受损的背景下,启动恢复上诉机制的谈判,应是推动WTO改革的优先事项和中国的选项。近年来,美国企图利用其他成员恢复上诉机制的动机以引入针对“非市场导向的政策和做法”的规则。拜登政府近期的动作表明美国前述意图已经有所松动。在各界提出的上诉机制改革新方案中,“沃克原则”和“伍尔夫建议”因应美国诉求以推动美国支持上诉机制改革,具有可行性。包括中国在内的WTO成员方应抓住此契机,了解并梳理美国关于上诉机制的诉求,逐项考虑其可接受性,以此推动上诉机制的改革。