Anatomical Retrofitting:Pi(脾)as Spleen and the Persistence of Ontological Ambivalence

Over the past decade,medical researchers in China have debated whether the Pi(脾)corresponds to the biomedical spleen or pancreas.This debate exemplifies a broader phenomenon of“anatomical retrofitting”,or the anachronistic imposition of contemporary categories onto living historical objects.“Anatomical retrofitting”as a means of rectifying cases of mistranslation further positions the biomedical spleen and pancreas as representing ahistorical,universal truths.This framework gives rise to a conceptual binary:while the biomedical spleen is universalized as what philosophers may describe as“logical”ontology,the Pi connects to a different nature of reality,or“metaphysical”ontology.Far from being an object of imprecision,the Pi was a dynamic vessel that also shared characteristics with the humoral spleen.Given that scholars in China have already subjected Pi to historical scrutiny,this paper urges scholars to do the same with biomedical anatomy.For instance,historically situating the humoral spleen demonstrates that it became less known and less articulated as it transformed into the biomedical spleen.Meanwhile,the pancreas remained an unstable epistemic object that took on the dynamic functions of the humoral spleen in nineteenth-century organotherapy.Through primary source analysis and literature review,this paper contends that the apparent ontological incommensurability between Pi and spleen is neither mutually exclusive nor irreconcilable.Instead,the dynamic nature of internal viscera,their many functions,and their participation in epistemic practices contribute to an ongoing ontological ambivalence that persists despite the forced certainty of anatomical retrofitting.

Rolling Decision Model of Thermal Power Retrofit and Generation Expansion Planning Considering Carbon Emissions and Power Balance Risk

With the increasing urgency of the carbon emission reduction task,the generation expansion planning process needs to add carbon emission risk constraints,in addition to considering the level of power adequacy.However,methods for quantifying and assessing carbon emissions and operational risks are lacking.It results in excessive carbon emissions and frequent load-shedding on some days,although meeting annual carbon emission reduction targets.First,in response to the above problems,carbon emission and power balance risk assessment indicators and assessment methods,were proposed to quantify electricity abundance and carbon emission risk level of power planning scenarios,considering power supply regulation and renewable energy fluctuation characteristics.Secondly,building on traditional two-tier models for low-carbon power planning,including investment decisions and operational simulations,considering carbon emissions and power balance risks in lower-tier operational simulations,a two-tier rolling model for thermal power retrofit and generation expansion planning was established.The model includes an investment tier and operation assessment tier and makes year-by-year decisions on the number of thermal power units to be retrofitted and the type and capacity of units to be commissioned.Finally,the rationality and validity of the model were verified through an example analysis,a small-scale power supply system in a certain region is taken as an example.The model can significantly reduce the number of days of carbon emissions risk and ensure that the power balance risk is within the safe limit.

Wind Turbine Noise Reduction through Blade Retrofitting

This paper outlines a plan for the effective reduction of the audible sound level produced by aerodynamic noise from the power-generating turbine blades. The contribution of aerodynamic noise can be divided into two categories: inflow turbulence and airfoil self-noise. The base model and retrofit blade designs were modeled in SolidWorks. Subsequently, noise prediction simulations were conducted and compared to the base blade model to determine which modification provided the greatest benefit using SolidWorks Flow Simulation. The result of this project is a series of blade retrofit recommendations that produce a more acoustically efficient design and reduce noise complaints while enabling turbines to be placed in locations that require quieter operations.

Numerical Calculations and Cold Tests for Flow Fields of a 220t/h Retrofitted Oil-Boiler

In this paper, cold simulation experiments and numerical calculations are conducted to predict 3 D flow field aerodynamics for an oil furnace after being retrofitted due to its fuel variation. K ε model and SIMPLE program under body fit coordination (BFC) system, in which TTM non orthogonal method is used to control the irregular geometric boundary, are adopted to solve the control equations. Model tests are conducted to check the calculation results, showing that they are in agreement with each other. Three different alternatives with different side window locations are also calculated to optimize the designs. The field retrofitting results show that the combination of cold tests with numerical calculations has prosperous application in retrofitting or renewing medium and small boilers.

Strategy for Energy Efficiency Retrofit of Rural Buildings in Hot-summer and Hold-winter Zone——A Case Study in Xinjiang New District,Jiangxi

Under the background of new urbanization, rural buildings＇ energy efficiency retrofit is an essential part of the overall work of the building energy conservation. Therefore, taking rural buildings in hot-summer and cold-winter zone as the research object, we carried out field investigation by combining geographical climate charactedstics with social-economic conditions and analyzed the energy consumption and energy conservation of rural buildings in hot-summer and cold-winter zone. On the basis of the investigation and analysis, this paper pointed out the questions with its energy efficiency retrofit and proposed the energy-saving strategy which was suitable for rural buildings in hot-summer and cold-winter zone based on people＇s livelihood and development.

考虑多功能区低碳改造与氢能多模式利用低碳特性的综合能源系统不确定性协同规划方法

随着碳中和目标的推进,综合能源系统(integrated energy system,IES)以其多能耦合、能量梯级利用等优势,逐渐成为能源供应的重要发展方向。在具有差异化用能需求的多功能区IES之间实现协同规划与调度,对提高系统经济性、降低系统碳排放有着重要作用。然而,由于碳捕集机组、多类型氢能利用设备等低碳元件的接入以及可再生能源发电的不断增加,随之而来的元件模型非凸性与系统内多类型不确定性对系统规划的影响亟需研究。对此,该文考虑了机组低碳改造和氢能多模式利用低碳特性,提出了一种针对多功能区综合能源系统的不确定性协同规划方法。首先,详细分析了多功能区供/用能特性与多能互补关系,构建了具有分区差异化特征的多功能区设备规划策略。其次,建立了低碳改造后的热电联产机组和氢能多模式利用设备的数学模型,并对其低碳特性进行了分析。基于此,为应对规划周期内系统低碳改造成本的不确定性和短期内可再生能源出力的不确定性,提出了一种混合长-短期不确定性的多功能区IES协同规划模型。通过基于二进制扩展的凸包线性化方法,对所提规划模型中的非线性约束进行凸化,并采用相应的迭代收缩求解算法实现模型的有效求解。最后,通过某实际多功能区IES算例进行仿真,结果验证了所提模型和所用算法的有效性。

基于ISM模型的老旧小区改造物业管理影响因素研究

时代不停发展,老旧小区改造工作方兴未艾,物业管理作为老旧小区改造三个“革命”中的“管理革命”是不可或缺的部分。为探究老旧小区改造物业管理发展的影响因素,文章在参考相关文献的基础上从政府、物业管理及业主3个维度出发,确定13个影响因素。运用ISM模型分析影响因素之间的关系,绘制影响因素层次结构图。结果显示:法律法规、服务意识等作为表层影响因素直接影响老旧小区改造物业管理发展;收费标准、监管机制等6个因素作为中间层影响因素;有关政策及经济水平作为深层影响因素根本影响其发展。最后根据研究结果提出相关建议,为将来老旧小区改造物业管理发展提供策略与参考。

上海虹桥国际机场航站楼绿色建筑实践案例解析

上海虹桥机场T1和T2航站楼已获得绿色建筑二星级运行标识,是依据《既有建筑绿色改造评价标准》GB/T 51141-2015开展运行评价的首个经上海市住建委认定的既有航站楼改造项目。虹桥机场T1和T2航站楼在运行后开展改扩建和既有航站楼改造提升工作,全面提升其绿色低碳性能。本文从规划与建筑、结构与材料、暖通空调、给水排水、电气、施工管理、运行管理七个方面出发,详细介绍了虹桥机场航站楼在设计、施工、运行管理全过程的绿色低碳实践工作,为既有航站楼的绿色建筑标识认证提供了借鉴和参考。

既有时速250 km高速铁路提速通信系统改造方案研究

为解决既有时速250 km的高速铁路提至更高速度时通信各子系统面临的技术改造问题,对通信各子系统的速度适应性以及提速改造方案进行研究。从技术标准层面,对通信各子系统与列车速度的关系进行分析。结合既有信号列控等级和GSM-R的覆盖方式,提出GSM-R系统的提速改造方案,并对传输系统、综合视频监控系统及电源设备的提速改造方案进行研究,可供类似工程借鉴参考。

Fragility curves of concrete bridges retrofitted by column jacketing

The Northridge earthquake inflicted various levels of damage upon a large number of Caltrans' bridges not retrofitted by column jacketing.In this respect,this study represents results of fragility curve development for two (2) sample bridges typical in southern California,strengthened for seismic retrofit by means of steel jacketing of bridge columns.Monte Carlo simulation is performed to study nonlinear dynamic responses of the bridges before and after column retrofit.Fragility curves in this study are represented by lognormal distribution functions with two parameters and developed as a function of PGA.The sixty (60) ground acceleration time histories for the Los Angeles area developed for the Federal Emergency Management Agency (FEMA) SAC (SEAOC-ATC CUREe) steel project are used for the dynamic analysis of the bridges. The improvement in the fragility with steel jacketing is quantified by comparing fragility curves of the bridge before and after column retrofit.In this first attempt to formulate the problem of fragility enhancement,the quantification is made by comparing the median values of the fragility curves before and after the retrofit.Under the hypothesis that this quantification also applies to empirical fragility curves developed on the basis of Northridge earthquake damage,the enhanced version of the empirical curves is developed for the ensuing analysis to determine the enhancement of transportation network performance due to the retrofit.

Effect of seismic retrofit of bridges on transportation networks

The objective of this research is to determine the effect earthquakes have on the performance of transportation network systems.To do this,bridge fragility curves,expressed as a function of peak ground acceleration(PGA)and peak ground velocity(PGV),were developed.Network damage was evaluated under the 1994 Northridge earthquake and scenario earthquakes.A probabilistic model was developed to determine the effect of repair of bridge damage on the improvement of the network performance as days passed after the event.As an example,the system performance degradation measured in terms of an index,'Drivers Delay,'is calculated for the Los Angeles area transportation system,and losses due to Drivers Delay with and without retrofit were estimated.

重庆地区既有办公建筑超低能耗改造技术措施研究

超低能耗技术是建筑领域高能效的节能减排实施路径,是对建筑能耗进行控制的重要技术措施。以重庆地区既有办公建筑为研究对象,运用能耗模拟软件,分析提升围护结构性能对空调冷热负荷的影响,研究既有办公建筑超低能耗改造的技术方案,为既有办公建筑超低能耗改造提供参考,对建筑存量市场的低能耗转型有一定指导意义。

Self-centering seismic retrofit scheme for reinforced concrete frame structures:SDOF system study

This paper presents the results of a parametric study of self-centering seismic retrofit schemes for reinforced concrete (RC) frame buildings. The self-centering retrofit system features flag-shaped hysteresis and minimal residual deformation. For comparison purpose,an alternate seismic retrofit scheme that uses a bilinear-hysteresis retrofit system such as buckling-restrained braces (BRB) is also considered in this paper. The parametric study was carried out in a single-degree-of-freedom (SDOF) system framework since a multi-story building structure may be idealized as an equivalent SDOF system and investigation of the performance of this equivalent SDOF system can provide insight into the seismic response of the multi-story building. A peak-oriented hysteresis model which can consider the strength and stiffness degradation is used to describe the hysteretic behavior of RC structures. The parametric study involves two key parameters -the strength ratio and elastic stiffness ratio between the seismic retrofit system and the original RC frame. An ensemble of 172 earthquake ground motion records scaled to the design basis earthquake in California with a probability of exceedance of 10% in 50 years was constructed for the simulation-based parametric study. The effectiveness of the two seismic retrofit schemes considered in this study is evaluated in terms of peak displacement ratio,peak acceleration ratio,energy dissipation demand ratio and residual displacement ratio between the SDOF systems with and without retrofit. It is found from this parametric study that RC structures retrofitted with the self-centering retrofit scheme (SCRS) can achieve a seismic performance level comparable to the bilinear-hysteresis retrofit scheme (BHRS) in terms of peak displacement and energy dissipation demand ratio while having negligible residual displacement after earthquake.

Experience on offshore cathodic protection retrofitting in the northern South China Sea

Platforms I and II are steel structures located in offshore areas southeast of the Zhujiang (Pearl) River Delta, the northern South China Sea,. in about 110 in water depth. The jackets, with aluminum sacrificial anodes for cathodic protection (CP) of the immersed zone, were launched in March 1995. In May 096 a CP survey showed that, after almost one year of service, a low polarization level had been achieved and some extended unprotected zones existed; mainly in the deepest part of the Platform II. Further to this, a joint activity was decided in order to assess the need of a possible retrofitting of the CP systems. The results of the activity carried out are dealt with, including technical and economical comparisons amongst several retrofitting options, both with sacrificial anodes and with impressed current systems. The adopted solution is illustrated and data are reported on the level of protection presently achieved.

Seismic design or retrofit of buildings with metallic structural fuses by the damage-reduction spectrum

Recently, the structural fuse has become an important issue in the field of earthquake engineering. Due to the trilinearity of the pushover curve of buildings with metallic structural fuses, the mechanism of the structural fuse is investigated through the ductility equation of a single-degree-of-freedom system, and the corresponding damage-reduction spectrum is proposed to design and retrofit buildings. Furthermore, the controlling parameters, the stiffness ratio between the main frame and structural fuse and the ductility factor of the main frame, are parametrically studied, and it is shown that the structural fuse concept can be achieved by specific combinations of the controlling parameters based on the proposed damage-reduction spectrum. Finally, a design example and a retrofit example, variations of real engineering projects after the 2008 Wenchuan earthquake, are provided to demonstrate the effectiveness of the proposed design procedures using buckling restrained braces as the structural fuses.

Pseudo-dynamic tests on masonry residential buildings seismically retrofitted by precast steel reinforced concrete walls

A retrofitting technology using precast steel reinforced concrete（PSRC） panels is developed to improve the seismic performance of old masonry buildings. The PSRC panels are built up as an external PSRC wall system surrounding the existing masonry building. The PSRC walls are well connected to the existing masonry building, which provides enough confinement to effectively improve the ductility, strength, and stiffenss of old masonry structures. The PSRC panels are prefabricated in a factory, significantly reducing the situ work and associated construction time. To demonstrate the feasibility and mechanical effectivenss of the proposed retrofitting system, a full-scale five-story specimen was constructed. The retrofitting process was completed within five weeks with very limited indoor operation. The specimen was then tested in the lateral direction, which could potentially suffer sigifnicant damage in a large earthquake. The technical feasibility, construction workability, and seismic performance were thoroughly demonstrated by a full-scale specimen construction and pseudo-dynamic tests.

Spectral and fragility evaluations of retrofitted structures through strength reduction and enhanced damping

A retrofit procedure for existing buildings called the ＂weakening and damping technique＂ （WED） is presented in this paper. Weakening of structures can limit the maximum response accelerations during severe ground motions, but leads to an increase in the displacements or inter-story drifts. Added damping by using viscous dampers, on the other hand, reduces the inter-story drifts and has no significant effect on total accelerations, when structures behave inelastically. The weakening and damping technique addresses the two main causes for both structural and nonstructural damage in structures. The weakening retrofit is particularly suitable for structures that have overstressed components and weak brittle components. In this paper, the advantages of the WeD are verified by nonlinear dynamic analysis and simplified spectral approach that has been modified to fit structures with additional damping devices. A hospital structure located in the San Fernando Valley in California is selected as a case study. The results from both analyses show that the retrofit solution is feasible to reduce both structural acceleration and displacement. A sensitivity analysis is also carried out to evaluate the effectiveness of the retrofitting method using different combinations of performance thresholds in accelerations and displacements through fragility analysis.

Effectiveness of two conventional methods for seismic retrofit of steel and RC moment resisting frames based on damage control criteria

This study investigates the efficiency of two types of rehabilitation methods based on economic justification that can lead to logical decision making between the retrofitting schemes. Among various rehabilitation methods, concentric chevron bracing（CCB） and cylindrical friction damper（CFD） were selected. The performance assessment procedure of the frames is divided into two distinct phases. First, the limit state probabilities of the structures before and after rehabilitation are investigated. In the second phase, the seismic risk of structures in terms of life safety and financial losses（decision variables） using the recently published FEMA P58 methodology is evaluated. The results show that the proposed retrofitting methods improve the serviceability and life safety performance levels of steel and RC structures at different rates when subjected to earthquake loads. Moreover, these procedures reveal that financial losses are greatly decreased, and were more tangible by the application of CFD rather than using CCB. Although using both retrofitting methods reduced damage state probabilities, incorporation of a site-specific seismic hazard curve to evaluate mean annual occurrence frequency at the collapse prevention limit state caused unexpected results to be obtained. Contrary to CFD, the collapse probability of the structures retrofitted with CCB increased when compared with the primary structures.

Resilience-based retrofitting of existing urban RC-frame buildings using seismic isolation

The improvement of the seismic resilience of existing reinforced-concrete(RC) frame buildings, which is essential for the seismic resilience of a city, has become a critical issue. Although seismic isolation is an effective method for improving the resilient performance of such buildings, target-oriented quantitative improvements of the resilient performance of these buildings have been reported rarely. To address this gap, the seismic resilience of two existing RC frame buildings located in a high seismic intensity region of China were assessed based on the Chinese Standard for Seismic Resilience Assessment of Buildings. The critical engineering demand parameters(EDPs) affecting the seismic resilience of such buildings were identified. Subsequently, the seismic resilience of buildings retrofitted with different isolation schemes(i.e., yield ratios) were evaluated and compared, with emphasis on the relationships among yield ratios, EDPs, and levels of seismic resilience. Accordingly, to achieve the highest level of seismic resilience with respect to the Chinese standard, a yield ratio of 3% was recommended and successfully applied to the target-oriented design for the seismic-resilience improvement of an existing RC frame building. The research outcome can provide an important reference for the resilience-based retrofitting of existing RC frame buildings using seismic isolation in urban cities.

Seismic retrofitting of reinforced concrete frame structures using GFRP-tube-confined-concrete composite braces

This paper presents a new type of structural bracing intended for seismic retrofitting use in framed structures. This special composite brace, termed glass-fiber-reinforced-polymer （GFRP）-tube-confined-concrete composite brace, is comprised of concrete confined by a GFRP tube and an inner steel core for energy dissipation. Together with a contribution from the GFRP-tube confined concrete, the composite brace shows a substantially increased stiffness to control story drift, which is often a preferred feature in seismic retrofitting. An analysis model is established and implemented in a general finite element analysis program - OpenSees, for simulating the load-displacement behavior of the composite brace. Using this model, a parametric study of the hysteretic behavior （energy dissipation, stiffness, ductility and strength） of the composite brace was conducted under static cyclic loading and it was found that the area ratio of steel core to concrete has the greatest influence among all the parameters considered. To demonstrate the application of the composite brace in seismic retrofitting, a three-story nonductile reinforced concrete （RC） frame structure was retrofitted with the composite braces. Pushover analysis and nonlinear time-history analyses of the retrofitted RC frame structure was performed by employing a suite of 20 strong ground motion earthquake records. The analysis results show that the composite braces can effectively reduce the peak seismic responses of the RC frame structure without significantly increasing the base shear demand.