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61.
以提高铅铋快堆的经济性与固有安全性为目标,开展100 MWt超长寿命小型自然循环铅铋快堆SPALLER-100概念设计,在选用PuN-ThN燃料和208Pb-Bi冷却剂的基础上,提出了一种添加固体慢化剂BeO的燃料组件设计方案,开展了堆芯布置研究和控制棒系统设计,分析了堆芯物理特性与稳态自然循环特性。结果表明:在低燃料装载量和小堆芯体积条件下,SPALLER-100堆芯换料周期达32 a,平均卸料燃耗高达210.38 MW·d/kg(HM),整个寿期内的反应性系数均为负值。稳态运行工况下燃料包壳、芯块最大温度均小于安全限值,反应堆具备一回路自然循环能力和一定流量自动分配能力。  相似文献   
62.
This study presents systematic packaging design tools integrating functional and environmental consequences on product life cycle. To design packaging for sustainability, the trade-offs between functional and environmental aspects of packaging throughout the product life cycle should be considered. However, it is difficult for packaging designers to understand the overall trade-offs because the extent of the design consequences on the entire life cycle of packaging and its contents is unclear. We developed two tools for packaging design: the Life Cycle Association Matrix (LCAM) and the Function Network Diagram (FND). The following three steps, based on literature reviews and interviews with industrial experts, were applied. Firstly, we listed the product functions and design variables related to the functions as the attributes allocated to the product life cycle. Secondly, the attributes were connected appropriately based on causal relationships. Lastly, we identified the factors to support decision making in the packaging design procedure. As a result, the LCAM depicts the design consequences on the life cycle, and the FND determines the stakeholders affected by the design consequences. Two case studies were demonstrated to analyze the trade-offs by using our tools. In the case studies, a liquid laundry detergent bottle and a milk carton were redesigned. The tools identified the design consequences and stakeholders affected by the redesign of the usability and protective function for the detergent and milk cases, respectively. The results showed the significance of understanding the design consequences on the product life cycle by integrating the functional and environmental aspects.  相似文献   
63.
Accurate remaining useful life (RUL) prediction of proton exchange membrane fuel cells (PEMFCs) can assess the reliability of fuel cells to determine the occurrence of failures and mitigate their operational risk. However, is it quite challenging to design a high-precision prediction method because the implicit degradation details of PEMFCs are difficult to learn well from the measurement data with high-frequency noise. Recognizing this, a novel RUL prediction method based on singular spectrum analysis (SSA) and deep Gaussian process (DGP) is proposed in this paper. The SSA-based method is firstly employed to preprocess the measurement data, which can strengthen the effective information of PEMFC degradation data at the same time remove the noise and spikes that interfere with degradation prediction. As a deep structural model, DGP has strong feature learning ability which can represent the nonlinear details of degradation data and give more accurate prediction results. At the same time, it serves as a probabilistic model that can provide the confidence interval to enhance reliability of RUL prediction. The effectiveness of the proposed method is evaluated by experimental data of the PEMFCs under steady-state conditions, and the results show that the SSA-DGP method has higher accuracy and reliability than conventional methods.  相似文献   
64.
Abstract

Once celebrated as a tourist destination, and now filled with derelict hotels, Varosha is a contested landscape at once embodying contradicting political and economic aspirations and featuring vividly in negotiations for political reconciliation in Cyprus. This paper provides a history of the antagonisms that surround this area by interrogating the creation of hotels and landscapes of leisure in 1960s Varosha and by exposing how these aspired to transform the cultural identity of the entire island. Casting the spotlight on the Golden Sands hotel, the paper demonstrates that, along with advancing iconographies of global modernity, hotel design was insidiously shaped by ethnic disputes as well as socio-economic and environmental contestations. Seen in the context of other conflict-torn cities, this history of the contested landscape of Varosha provides crucial insights into the imbrications of architectural history and design practices in the management of contested instances of modern, twentieth-century heritage.  相似文献   
65.
柴保明  魏琛 《煤矿机械》2020,41(3):88-91
为了解直线振动筛侧板裂纹的综合性能,首先对侧板进行静力学分析得到侧板危险区域。其次对该区域进行裂纹布置,应用断裂力学理论对振动筛侧板进行应力强度因子的计算,分析侧板危险区域裂纹扩展特性,同时针对不同形状、大小的裂纹进行参数分析,得到振动筛侧板裂纹扩展规律。最后对侧板进行疲劳寿命计算,得到含初始裂纹处侧板的疲劳寿命及安全系数,为侧板的设计优化提供理论指导。  相似文献   
66.
Exploring high ion/electron conductive olivine-type transition metal phosphates is of vital significance to broaden their applicability in rapid-charging devices. Herein, we report an interface engineered LiFe0.5Mn0.5PO4/rGO@C cathode material by the synergistic effects of rGO and polydopamine-derivedN-doped carbon. The well-distributed LiFe0.5Mn0.5PO4 nanoparticles are tightly anchored on rGO nanosheet benefited by the coating of N-doped carbon layer. The design of such an architecture can effectively suppress the agglomeration of nanoparticles with a shortened Li+ transfer path. Meantime, the high-speed conducting network has been constructed by rGO and N-doped carbon, which exhibits the face-to-face contact with LiFe0.5Mn0.5PO4 nanoparticles, guaranteeing the rapid electron transfer. These profits endow the LiFe0.5Mn0.5PO4/rGO@C hybrids with a fast charge-discharge ability, e.g. a high reversible capacity of 105 mAh·g-1 at 10 C, much higher than that of the LiFe0.5Mn0.5PO4@C nanoparticles (46 mA·h·g-1). Furthermore, a 90.8% capacity retention can be obtained even after cycling 500 times at 2 C. This work gives a new avenue to fabricate transition metal phosphate with superior electrochemical performance for high-powerLi-ion batteries.  相似文献   
67.
李华  沈旸 《建筑师》2019,(5):4-6
建筑评论是一项针对具体对象,将目之所及的事物背后不可视的背景、思想、价值判断、驱动力等,转化为可以言说、可以讨论、具有建筑学和文化社会意义的思辨性活动。[1]这项活动的基础工作之一是概念的辨析与运用。因此,在东南大学建筑学院开设的"建筑评论课",通过课程主题的组织,在帮助学生建立多维批评视野的同时,以概念辨析为切入点,通过基于精读、研究的写作训练,实现思辨性思维的培养、学术素养和写作的培训,以及对建筑评论和中国现当代建筑话语的理解。  相似文献   
68.
Javier de Mesones-Cabello was an influential and active planner of the 1960s and 1970s in Spain, who passed away in December, 2016. His professional career as a self-taught urban planner was extensively linked to his academic and institutional activities. These connections supported the establishment of relationships with prestigious professionals working in urban planning practice. In planning the 1969 masterplan for the city of Valladolid, in Spain, de Mesones-Cabello made several intellectual references to the Greek urban planner Doxiadis. This masterplan covers a relatively unknown example of directional city growth in a European context. My findings elucidate the extent to which de Mesones-Cabello was influenced by Doxiadis, and the circumstances in which these ideas have continued to dominate thinking about Valladolid's urban development.  相似文献   
69.
This study evaluated the effect of dry white mulberry and walnut paste (Gobdin, a traditional Turkish food) in probiotic yogurt on the survival of Lactobacillus acidophilus and yogurt properties. Six different yogurts were produced with 0%, 5% and 10% Gobdin using Lactobacillus bulgaricus + Streptococcus thermophilus and with 0%, 5% and 10% Gobdin using L. bulgaricus + S. thermophilus + L. acidophilus. The physical, chemical, microbiological and sensorial properties of the yogurts were evaluated based on storage at 4 ± 1 °C. Probiotic shelf life and the most suitable combinations were determined. The highest L. acidophilus count (8.65 log cfu g?1) was found in the 5% Gobdin‐supplemented yogurt on the 7th day of storage, while the lowest count (8.11 log cfu g?1) was found in the probiotic control yogurt on the 21st day. Although the L. acidophilus counts in the probiotic yogurts declined during storage, all values found throughout the 21‐day storage period were >8 log cfu g?1. This is above the level necessary to provide the desired therapeutic effect in probiotic products (106–107 cfu g?1). The highest overall acceptability score was obtained on the first day from the yogurt with 5% Gobdin. However, all yogurt samples had general acceptability scores between 7 and 8 points from a 9‐point maximum. Thus, this study determined that a new functional yogurt can be produced using L. acidophilus with 5% Gobdin.  相似文献   
70.
为分析高速列车转向架构架损伤、等效应力及寿命分布特性,对构架疲劳关键测点进行动应力线路实测并对测点实测时域数据波形进行解析;基于实测应力时间历程及雨流计数法编制二维应力谱,利用Goodman等寿命方程将二维应力谱等效转换为一维应力谱;阐述线性累积损伤及非线性累积损伤模型的建立方法并对实测数据的线性累积损伤及非线性累积损伤进行了计算及对比分析;分别基于线性累积损伤理论及非线性累积损伤理论推导出各理论下的等效应力,基于实测数据对两种等效应力进行了计算及对比分析;通过结合非线性累积损伤及线性累积损伤理论计算的等效应力及不同可靠度下的材料S-N曲线计算并对比分析构架结构的疲劳寿命。研究结果表明,与非线性疲劳分析理论相比,线性疲劳分析理论对高速列车转向架构架的疲劳特性评估偏于保守。  相似文献   
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