| 水平微圆管内R22和R410a凝结压降的实验研究 |
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张会勇 李俊明 王补宣
（清华大学热能工程系 北京 100084）
摘 要 R410a是一种被广泛看好的R22替代物，研究R410a的凝结压降特性对开发适用此种制冷工质的凝结换热设备有重要意义。搭建了微细尺度凝结压降实验台，实验研究了R22和R410a在内径为0.941mm水平不锈钢圆管内饱和温度为40℃、质量流速为200～1000 kg/m2?s、干度为0.2～0.8时的凝结压降特性。实验结果表明：凝结压降随着质量流速的增大而增大，在较高干度时更加明显。与R22相比，R410a的凝结压降在较低干度和质量流速时与R22相当，在较高干度和较高质量流速时明显低于R22。 关键词 工程热物理；压降；微圆管；凝结；实验研究 |
关键词 工程热物理；压降；微圆管；凝结；实验研究
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Experimental Investigation on Pressure Drop of R22 and R410a during
Stanley P. Burg☆ and Zheng Xianzhang Zhang Huiyong☆，Li Junming,Wang Buxuan
☆Department of Thermal Engineering, Tsinghua University，Beijing,100084，China AbstractR410a is known as one of the substitutes for R22 and it is important to study the pressure drop of R410a during condensing processes. A test rig was established to measure pressure drop in micro scale and characteristics of pressure drop of R22 and R410a in a horizontal stainless round tube with an inner diameter of 0.941 mm during condensing processes were investigated experimentally at the saturation temperature of 40℃. The mass flux varied within the range of 200-1000 kg/m2s and the vapor quality 0.2-0.8．The experiment results indicate that pressure drop increases with mass flux and vapor quality and more obviously in high vapor quality region. The pressure drop of R410a is equivalent to that of R22 at low vapor quality and mass flux but obviously lower than that of R22 at higher vapor quality and mass flux.
KeywordsEngineering thermophysics； Microtube； Condensation； Pressure drop； Experimental investigation |
| 蒸发器亲水性对空调性能影响的试验研究 |
杨 强 戴立生
(中国建筑科学研究院空调所 北京 100013) |
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摘 要 采用平衡环境型房间量热计测试了亲水性不同的三组铜翅片蒸发器在不同含湿量下空调制冷性能，测试结果显示，在低湿时，除湿量较小，凝结水排除能力足够，亲水性改善空调制冷性能作用不大，在高湿时，除湿量较大，需要较强的凝结水排出能力，亲水性改善空调制冷性能作用明显。
关键词 热工学;空调;蒸发器;亲水性;含湿量 |
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Experimental Research on Effect of Evaporator Surface Wettability on Air-conditioner Performance
Yang Qiang☆, Dai Lisheng
☆Air conditioning research department of China academy of building research, Beijing,100013,China
Abstract Performance tests were conducted on three finned tube evaporators, which included one untreated copper fin evaporator, two hydrophilic treated copper fin evaporators. Each evaporator was tested with it being installed in the indoor unit of a cabinet-type air conditioner, which was used as the platform of the performance tests. Tests were conducted using the calorimeter method under the different humidity air conditions. The results showed that the evaporator surface wettability has notable effect on the air conditioner performance at high humidity air conditions because of strong ability to discharging great dew water, not at low humidity air conditions because of less water condensate.
Keywords Pyrology; Air conditioner; Evaporator; Wettability; Humidity |
| 界面活性剂的混合添加对溴化锂溶液吸收水蒸气的影响 |
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高洪涛 李 豪
（大连海事大学制冷与低温工程研究所 大连 116026） |
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摘 要 在静态池吸收实验中将两种有效添加剂混合添加，测试其对溴化锂水溶液吸收水蒸气的影响，从而探寻不同界面活性剂之间的促进或者抑制作用。通过对正辛醇、仲辛醇、异辛醇、正己醇四种物质采用单种添加和两种混合添加的测试实验表明，混合添加后的效果与其中较好的添加剂单独添加的效果接近，例如，正辛醇在四种添加剂中效果最好，其它添加剂与正辛醇混合添加的效果都与正辛醇单独添加时的效果相近。 关键词 工程热物理；吸收量；静态池；界面活性剂；溴化锂水溶液 |
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Effect of Compound Surfactants on Water Vapor Absorption of Aqueous LiBr Solution
Gao Hongtao, Li Hao
☆Institute of Refrigeration & Cryogenics Engineering , Dalian Maritime University, Dalian,116026, China
AbstractCompound surfactants were added to aqueous LiBr solution in static pool setup to study their effect on water vapor absorption of aqueous LiBr solution. 1-Octanol, 2-Octanol, 2-Ethyl-1-hexanol, and 1-Hexanol were added to 60w LiBr solution individually and in the mixture form of two surfactants. The experimental result shows that the effect of compound surfactants is near to the better one between them，for example, 1-Octanol is the best one during these four additives, the effect of any other additive mixed with 1-Octanol is near to the effect of 1-Octanol alone.
KeywordsEngineering thermophysics; Absorption mass; Stagnant pool absorber; Surfactant; Aqueous LiBr solution |
| 毛细管气体流量特性研究 |
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冯利峰 黄晓峰 闫志恒
（广东科龙空调器有限公司 顺德 528303） |
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摘 要通过实验研究，得出了气体在毛细管中流动时的沿程能量损失规律，经过数据处理，拟合出了毛细管的气体流量随毛细管内径、长度的变化曲线及其变化率曲线，得出了其韦泊分布函数。拟合出了毛细管的气体流量随压力差变化的曲线及其直线函数。为制冷系统的设计匹配以及毛细管批量生产的质量检验提供了一些非常有益的参考。[JP]
关键词动力机械工程；毛细管气体流量特性；毛细管气体流量分布函数；曲线拟合；DPS数据处理；制冷系统匹配；毛细管检验 |
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Research on Gas Flow Characteristics in Capillary Tube
Feng Lifeng☆, Huang Xiaofeng,Yan Zhiheng
☆ Guangdong Kelon air-conditioner Co.,Ltd.,Shunde,52830,China
AbstractEnergy loss for a gas flowing inside a capillary tube was obtained experimentally. With data processing, the curves of the gas flow rate change with different lengths and inner diameters for the capillary tube were achieved. The gas flow rate change curves inside the capillary tube with the pressure difference were imitated.
Keywords Power machinery and engineering; Capillary tube gas flux speciality; Capillary tube gas flux distributing function; Curve imitate; DSP data processing; Refrigeration system matching; Capillary tube check up |
| 一种蜂窝纸毡填料用于除湿液体再生过程的实验研究 |
陈 颖 张永权 史保新
(广东工业大学材料与能源学院 广州 510006) |
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摘 要设计出一种采用新型蜂窝状“纸毡”砌成的填料塔，用来进行除湿溶液在一定工况下与空气的再生试验。在控制溶液浓度、流量以及进口空气状态的条件下，分别研究了空气流量、溶液温度以及填料层高度对溶液再生性能的影响趋势，并分析了各因素对再生性能的控制机理。通过对试验数据的整理，得到了几种填料厚度下平均Sh数的变化规律。
关键词 热工学；液体除湿；实验研究；再生性能；填料结构 |
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Experimental Investigation on Liquid Desiccant Regeneration in Packed
Tower with Honeycomb Paper Chen Ying☆, Zhang Yongquan,Shi Baoxin
☆ Guangdong University of Technology, Guangzhou,510006,China
AbstractA regeneration tower with honeycomb paper to be its packed material wa s developed. Experiments were conducted to investigate the influence of air flow, solution temperature and height of packed material on its regeneration performance with the fixed inlet air states, solution concentration and flow rate. The experimental results indicate that the mass transfer increases when the solution temperature increases and MR decreases. In addition, The change of the mean Sherwood number at several heights of packed material was obtained.
KeywordsPyrology; Liquid desiccant; Experiment study; Regeneration performance; Structure of packed material |
| 基于双流体模型的立式陈列柜风幕风口模型 |
余克志1, 2 丁国良1 陈天及2
（1.上海交通大学制冷与低温工程研究所〓上海〓200030；?2.上海水产大学制冷工程系上海 200090） |
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摘 要根据立式陈列柜风幕广泛采用的蜂窝板风口的特点，提出了基于双流体模型的风口模型。风口的双流体模型以流动状态划分两种流体，即分别以陈列柜内原有空气和通过风幕流入的空气来区分两种流体。通过风幕流入的空气的容积分数取为蜂窝板的面积系数。两种流体之间的质量、动量和能量交换采用经验关系式处理。通过对模拟计算结果的分析，发现与传统简单风口模型相比，风口的双流体模型与实验测试结果更为吻合，是很有价值的风幕模型。 关键词 热工学；风口模型；双流体模型；风幕；陈列柜 |
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Two-Fluid Model for Air Supply Opening of Air Curtain in Vertical Display Case
Yu Kezhi☆, Ding Guoliang,Chen Tianji
☆Institute of Refrigeration and Cryogenics，Shanghai Jiaotong University, Shanghai, 200030，China
AbstractConsidering the characteristics of linear grill which is widely used in vertical display cases, a two-fluid model for the air supply opening was set up. In the model the two fluids were defined as the original air in the display case and the inlet stream through the air curtains. The volume fraction of the inlet stream was defined as the area coefficient of linear grill. The mass transfer, momentum transfer, and energy transfer between two fluids were computed with empirical equations. The computational results show that the two-fluid model of air supply opening is in more agreement with the experiment than the conventional simple opening model.
Keywords Pyrology; Air supply opening model; Two-fluid model; Air curtain; Display case |
| 直接蒸发内融式冰蓄冷空调的蓄冷和释冷特性 |
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杜艳利1，2 何世辉1 肖 睿1，2 黄 冲1 冯自平1
(1.中国科学院广州能源研究所 广州 510640；2.中国科学院研究生院 北京 100039) |
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摘 要 直接蒸发内融式冰蓄冷空调是一种新型的冰蓄冷技术，具有换热效率高，使用范围广等优点。在一台变频空调器基础上，通过新增蓄冰槽、换热盘管、控制阀等设备改制构成直接蒸发内融式冰蓄冷空调实验系统。研究了该空调系统的蓄冰和融冰两个过程中的冰槽内盘管传热特性和系统的运行动态特性，得到了蓄冷和释冷过程的性能曲线。实验结果表明，直接蒸发内融式冰蓄冷空调系统可以使得空调电力负荷转移率达到23%左右。通过实验研究可以为直接蒸发内融式冰蓄冷空调产品的设计开发提供实验基础，具有一定的工程运用价值。
关键词 热工学；直接蒸发内融式冰蓄冷空调；蓄冰；融冰；传热；动态特性 |
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Characteristics of The Charging Process and Discharging Process of Direct
Evaporative Internal-melt Ice Storage System
Du Yanli☆,He Shihui,Xiao Rui,Huang Chong,Feng Ziping
☆ Guangzhou Institute of Energy Conversion, the Chinese Academy of Sciences, Guangzhou,51064,China
AbstractThe direct evaporative internal-melt ice storage air conditioning is a new and promising ice-storage technology. It has high heat transfer efficiency and hence can be widely used. Through adding ice storage tank and heat transfer tubes and the control valves, a split-type inverter air-conditioner was reconstructed as an evaporative internal-melt ice storage air conditioning system. In this study, the heat-transfer properties in the ice storage tank and dynamic characteristics of the system about the charging process and discharging process were studied and the performance curves of the both processes were obtained. Experimental results show that the power load shift rate of the experimental system can reach about 23%.
KeywordsPyrology; Direct evaporative internal-melt ice storage system; Charging process; Discharging process; Heat transfer; Dynamic characteristic |
| 混合制冷剂饱和气体密度的推算 |
陈建新〓陈则韶〓胡凡〓王跃武
(中国科学技术大学热科学和能源工程系〓合肥〓230027) |
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摘 要 在对比态原则下，作者发现混合工质饱和气体密度与其纯组分饱和气体密度的无量纲对比关系有同一化规律；同时，还寻找到利用纯组分的临界点密度与临界压力拟合混合工质临界点密度与临界压力的关系式，确立了混合工质的这两个特征参数。进而给出了计算混合制冷剂饱和气体密度的通用方程，该方程是隐式的。比较了文献中5种二元和三元混合工质的推算值与文献值，误差基本在±2%内。
关键词 热工学；饱和气体密度；对比态；混合工质；推算 |
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Prediction of Saturated Vapor Density of Refrigerant Mixtures
Chen Jianxin☆, Chen Zeshao, Hu Peng, Wang Yuewu
☆ Dept. of Thermal Science & Energy Engineering, University of Science and Technology of China, Hefei, 230027, China
AbstractBased on the corresponding principle, it is found that the relationship between saturated vapor corresponding-density and corresponding-temperature for mixtures accorded with that for pure-components. Moreover, a method was obtained to calculate the critical density and critical pressure of refrigerant mixtures by using the critical density and critical pressure of pure-components and thus the characteristic parameters, the critical density and critical pressure of refrigerant mixtures, were achieved. Then the generalized equation that is implicit and used to calculate saturated vapor density of refrigerant mixtures was proposed. In addition, the values calculated were compared with the values in literature for five ternary and binary refrigerant mixtures and their deviation is less than 2%.
Keywords Pyrology；Air cycle heat pump；Dry technology；Energy efficiency |
| 冷壁面霜层生长的支持向量机模型 |
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任 能 谷 波
（上海交通大学制冷与低温研究所 上海 200240） |
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摘 要针对结霜过程因具有明显的非线性特征，采用传统方法难以精确预测的问题。建立了基于支持向量机的冷壁面霜成生长的预测模型，应用实验数据对模型进行验证、评估，并与基于最小二乘法的非线性多元回归模型进行了对比、分析。结果表明，基于支持向量机的预测模型能够很好的解决非线性预测问题。在已建立的预测模型基础上，以霜层生长过程中传热率预测为例，分别在测试集中的自变量与因变量加入不同噪声信号对模型预测性能影响进行了研究。结果表明，基于支持向量机的模型具有良好的抗干扰能力。 关键词 热工学；预测模型；支持向量机；结霜；噪声 |
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Predication Model of Frost Growth on Cold Surface Based on Support Vector Machine
Ren Neng☆, Gu Bo
☆ Institute of Refrigeration and Cryogenics , Shanghai Jiaotong University, Shanghai,200240,China
AbstractA novel machine learning method, support vector machine (SVM), was used to develop a prediction model for frost growth on cold surface. The prediction model was validated by experimental data. The values predicted were compared with those by multivariable nonlinear regression (NLR) model which is based on the least square method, and the results show that the SVM based model has a good prediction accuracy. Then the SVM based total heat flux prediction model was investigated as an example in the capability of dealing white noise signal by adding noise in the input vectors and the output vector of the training set. The result shows that the present SVM prediction models are robust against noise.
Keywords Pyrology； Prediction model; Support Vector Machine (SVM); Frost growth; Noise
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| 真空冷冻干燥过程参数对扇贝冻干升华干燥时间的影响 |
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李 敏 蒋小强 关志强
（广东海洋大学工程学院 湛江 524025） |
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摘 要 通过采用二次正交回归组合试验，建立了真空冷冻干燥升华时间和单位厚度升华时间的二次多元回归模型，利用降维法分析了真空冷冻干燥过程中物料厚度、干燥室压强和加热板温度三个主要过程参数对扇贝真空冷冻干燥升华干燥时间的影响。结果表明，物料厚度、干燥室压强和加热板温度对冻干时间影响呈二次函数规律变化，影响的主次因素依次为：物料厚度、干燥室压强、加热板温度。对单位厚度冻干时间进行岭嵴分析，给出了在本试验三因素取值范围内的冻干过程优化参数：物料厚度为9mm；干燥室压强为50Pa；加热板温度为39℃，优化的物料单位厚度升华干燥时间为0.146h。 关键词 食品加工技术；真空冷冻干燥升华时间；扇贝 |
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Experimental Study on Scallop Sublimation Time in Vacuum Freeze Drying
Li Min☆,Jiang Xiaoqiang,Guan Zhiqiang
☆ College of Engineer, Guangdong Ocean University,Zhanjiang，524025,China
AbstractOn the basis of the quadratic thogonal experiment , the mathematical models of time or energy consumption related to the material thickness, heating temperature, and pressure in a drying chamber were established by the SAS statistical software and F tests. The effects of the three main influence parameters above on the drying time and energy consumption were analyzed. The results indicate that the influence of the three parameters exhibits a quadratic function to the freeze drying time. Moreover, under the present experiment conditions, the importance sequence of the three factors is as follows: materials thickness, pressure in the drying chamber, and heating temperature. In our study, the optimal parameters were a thickness of 9mm, pressure of 50 Pa, and heating temperature of 39 ℃, and the unit thickness time of drying was 0.146h.
KeywordFood processing technology; The time of sublimation vacuum freeze-drying; Scallop
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| 不同的冷却方法和冷藏对小白菜（油菜）品质的影响 |
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刘 升 武田吉弘堀 茂 树
（1.国家蔬菜工程技术研究中心北京市农林科学院蔬菜研究中心 北京 100097;2.日本长野农业合试验场 长野 382）
摘 要 试验研究了小白菜采后真空冷却和空气冷却后，在2℃条件下冷藏7天、10天、14天、19天和29天的品质变化。结果表明：冷藏19天的小白菜新鲜并具有商品性。随着冷藏时间的延长，小白菜的失重率逐渐增多，颜色变浅，维生素C含量 和还原型维生素C含量逐渐降低，冷藏前10天小白菜的叶绿素含量变化不大，10天以后明显降低。真空冷却后的小白菜品质明显好于空气冷却后的小白菜品质，前者维生素C 、还原型维生素C、叶绿素含量的损失均低于后者，且真空冷却后2℃冷藏29天的小白菜仍具有商品性。 关键词 园艺学；真空冷却；空气冷却；冷藏；小白菜 |
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Effect of Different Cooling Method and Cold Storing on Quality of Pakchoi
Liu Sheng☆, Yosihiro Takeda,Sigeki Hori
☆ National Engineering Research Center for Vegetables, Beijing Vegetable Research Center, Beijing,100097,China
Abstract The quality changes of pakchoi in cold storage with vacuum cooling and air cooling, at 2℃ for 7 days, 10 days, 14 days, 19 days and 29 days were studied. The results show that the pakchoi with the marketability could be stored for 19 days at 2℃. During cold storage, the weight loss rate of pakchoi increased gradually; the color became light; Vitamin C and reducing Vitamin C contents decreased gradually; the change of chlorophyll content in first 10 days cold storage was not great but later the reduction of chlorophyll content was significant. In addition, the losses of Vitamin C, reducing Vitamin C and chlorophyll contents by vacuum cooling were lower than those by air cooling. The pakchoi with the marketablity by vacuum cooling could be stored for 29 days at 2℃
KeywordsHorticulture; Vacuum cooling; Air cooling; Cold storage; Pakchoi |
| 一种涡旋压缩机电流和功率因子计算模型的建立 |
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胡 健 文 航 谷 波
上海交通大学制冷与低温研究所 上海 200030）
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摘 要针对涡旋压缩机的运行电流，在经典性能方程的基础上进行了修正，建立了更精确，通用性更好的性能关联式。并针对涡旋压缩机的功率因子，提出了一种计算模型。在对大量的实验数据进行采集分析的基础上，运用多元非线性拟合方法求解出拟合系数。结果表明，由该方法建立的模型能够准确地描述变工况下涡旋压缩机的电流和功率因子，校核结果显示两个公式的平均相对误差分别为1.97%和1.503%。同时具有较好的通用性，适用于整个系列的压缩机的运行电流和功率因子的计算。 关键词动力机械工程;涡旋压缩机;电流;功率因子;关联式;多元非线性拟合 |
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New Modeling of Current and Power Efficiency for Scroll Compressor
Hu Jian ， Wen Hang , Gu Bo
☆ Inst. of Refrigeration and Cryogenics Eng., Shanghai Jiao tong Univ., Shanghai,200030, China
AbstractA new formula for compressor current was proposed by revision of the conventional formula and a formula for the calculation of the compressor power efficiency was also proposed. A multiple non-linear mathematical method was used to achieve fitted coefficient. The average related errors between the experiment data and the fitted data are 1.97% and 1.503%. The result shows that the present two calculation models can describe accurately the compressor performance and energy consumption for a whole series of scroll compressors.
KeywordsPower machinery and engineering;Scroll compressor; Current; Power efficiency; Formula; Multiple non-linear |
| 反问题法在相变材料热导性能研究中的应用 |
袁艳平1 杜雁霞2 程宝义2
（1.西南交通大学机械工程学院 成都 610031；2.南京解放军理工大学 南京 210007） |
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摘 要基于相变导热模型，提出将相界面运动的测试实验与数值计算相结合来求解有效导热系数的反问题法，对几种相变储能材料添加金属介质后导热系数的改善进行了研究。结果表明，金属介质的导热系数越大，则相变材料的有效导热系数也越大；在相同的添加比例下，低热导率相变材料有效导热系数的改善程度要大于高热导率相变材料。该方法的求解结果与相关文献吻合较好。 关键词 工程热物理；相变材料；导热性能；反问题法 |
Application of Inverse Problem Method in Investigation of Thermal Conductivity for PCMs
Yuan Yanping☆, Du Yanxia,Cheng Baoyi
☆ Southwest Jiaotong University,Chengdu,610031,China
AbstractBased on the model of phase change heat conduction , an inverse problem method combining phase interface motion experiment and numerical calculation was developed to study the improvement of thermal conductivity when metal is added in PCMs(Phase Change Materials ) .The results show that the greater the thermal conductivity of metal , the higher the effective therma conductivity of PCMs .It is indicated that when the a dded ratio of metal is the same, the improvement is greater for PCMs with low conductivity than that for PCMs with high conductivity . The results agree well with those in literature.
Keywords Engineering thermophysics; PCMs; Thermal conductivity; Inverse problem method |
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