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Genome-wide association study of the backfat thickness trait in two pig populations

Dandan ZHU,Xiaolei LIU,Rothschild MAX,Zhiwu ZHANG,Shuhong ZHAO,Bin FAN

《农业科学与工程前沿（英文）》 2014年第1卷第2期页码 91-95 doi: 10.15302/J-FASE-2014005

摘要： Backfat thickness is a good predictor of carcass lean content, an economically important trait, and a main breeding target in pig improvement. In this study, the candidate genes and genomic regions associated with the tenth rib backfat thickness trait were identified in two independent pig populations, using a genome-wide association study of porcine 60K SNP genotype data applying the compressed mixed linear model (CMLM) statistical method. For each population, 30 most significant single-nucleotide polymorphisms (SNPs) were selected and SNP annotation implemented using Build 10.2. In the first population, 25 significant SNPs were distributed on seven chromosomes, and SNPs on SSC1 and SSC7 showed great significance for fat deposition. The most significant SNP (ALGA0006623) was located on SSC1, upstream of the gene. In the second population, 27 significant SNPs were recognized by annotation, and 12 SNPs on SSC12 were related to fat deposition. Two haplotype blocks, M1GA0016251-MARC0075799 and ALGA0065251-MARC0014203-M1GA0016298-ALGA0065308, were detected in significant regions where the and genes were identified as contributing to fat metabolism. The results indicated that genetic mechanism regulating backfat thickness is complex, and that genome-wide associations can be affected by populations with different genetic backgrounds.

关键词： backfat thickness SNP chip genome-wide association study compressed mixed linear model pig

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Effects of sheet thickness and material on the mechanical properties of flat clinched joint

Chao CHEN, Huiyang ZHANG, Shengdun ZHAO, Xiaoqiang REN

《机械工程前沿（英文）》 2021年第16卷第2期页码 410-419 doi: 10.1007/s11465-020-0618-y

摘要： The flat clinching process is attracting a growing attention in the joining field of lightweight materials because it avoids the geometric protrusion that appears in the conventional clinching process. In this paper, the effects of sheet thickness and material on the mechanical properties of the clinched joint were studied. Al1060 and Al2024 sheets with 2 mm thickness were employed to develop the clinched joint by using different material configurations, and Al1060 sheets with 2.5- and 1.5-mm thicknesses were used to produce the clinched joint by using different thickness configurations. The clinched joints using various sheet configurations were sectioned, and dimensional analysis was conducted. Cross-tensile and shearing tests were carried out to analyze the mechanical properties of the clinched joint, including tensile strength, shearing strength, and absorbed energy. In addition, the failure modes of the clinched joints were discussed. Results indicated that the clinched joint with a stiff top sheet had increased static strength regardless of the test type. The clinched joint with a thick top sheet demonstrated lower static strength than the joint with a thick bottom sheet in the cross-tensile test. However, this result was reversed in the shearing tests. The flat clinching process has a great potential in joining dissimilar and various thickness materials.

关键词： clinched joint flat clinching process thickness configuration material configuration mechanical property

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Lamellar thickness transition of melt-crystallized polybuten-1 tetragonal phase: configurational change

Motoi YAMASHITA

《化学科学与工程前沿（英文）》 2009年第3卷第1期页码 26-32 doi: 10.1007/s11705-009-0002-2

摘要： Lamellar crystal thickness of isotactic polybutene-1 ( -PB1) have been investigated for crystallization in the melt over a wide range of crystallization temperature from 40°C to 90°C by small angle X-ray scattering experiments and density measurements. The crystal thickness demonstrates two linear dependences on inverse supercooling and a transition from one dependence to the other has been observed around = 65°C. Each of the two dependences obeys the nucleation theory in the high and low supercooling ranges, respectively. Chain folding free energy determined from the low supercooling range is larger than that determined from the high supercooling range. Possible mechanisms for the transition are discussed taking account of entropy of chain folding directions.

关键词： isotactic polybutene-1 tetragonal phase crystal thickness melt growth chain folding small angle X-ray scattering nucleation theory end surface free energy

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Determining the optimum economic insulation thickness of double pipes buried in the soil for district

Fating LI, Pengfei JIE, Zhou FANG, Zhimei WEN

《能源前沿（英文）》 2021年第15卷第1期页码 170-185 doi: 10.1007/s11708-020-0680-5

摘要： The insulation thickness (IT) of double pipes buried in the soil (DPBIS) for district heating (DH) systems was optimized to minimize the annual total cost of DPBIS for DH systems. An optimization model to obtain the optimum insulation thickness (OIT) and minimum annual total cost (MATC) of DPBIS for DH systems was established. The zero point theorem and fsolve function were used to solve the optimization model. Three types of heat sources, four operating strategies, three kinds of insulation materials, three buried depth (BD) values, and seven nominal pipe size (NPS) values were considered in the calculation of the OIT and MATC of DPBIS for DH systems, respectively. The optimization results for the above factors were compared. The results show that the OIT and MATC of DPBIS for DH systems can be obtained by using the optimization model. Sensitivity analysis was conducted to investigate the impact of some economic parameters, i.e., unit heating cost, insulation material price, interest rate, and insulation material lifetime, on optimization results. It is found out that the impact of sensitivity factors on the OIT and MATC of DPBIS for DH systems is different.

关键词： double pipes optimization model optimum insulation thickness minimum annual total cost

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Modeling of the minimum cutting thickness in micro cutting with consideration of the friction around

Tianfeng ZHOU, Ying WANG, Benshuai RUAN, Zhiqiang LIANG, Xibin WANG

《机械工程前沿（英文）》 2020年第15卷第1期页码 81-88 doi: 10.1007/s11465-019-0561-y

摘要： Friction modeling between the tool and the workpiece plays an important role in predicting the minimum cutting thickness during TC4 micro machining and finite element method (FEM) cutting simulation. In this study, a new three-region friction modeling is proposed to illustrate the material flow mechanism around the friction zone in micro cutting; estimate the stress distributions on the rake, edge, and clearance faces of the tool; and predict the stagnation point location and the minimum cutting thickness. The friction modeling is established by determining the distribution of normal and shear stress. Then, it is applied to calculate the stagnation point location on the edge face and predict the minimum cutting thickness. The stagnation point and the minimum cutting thickness are also observed and illustrated in the FEM simulation. Micro cutting experiments are conducted to validate the accuracy of the friction and the minimum cutting thickness modeling. Comparison results show that the proposed friction model illustrates the relationship between the normal and sheer stress on the tool surface, thereby validating the modeling method of the minimum cutting thickness in micro cutting.

关键词： tool friction minimum cutting thickness finite element method tool edge radius micro cutting

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Numerical simulation of compaction parameters for sand-filled embankment using large thickness sand filling

Wentao WANG, Chongzhi TU, Rong LUO

《结构与土木工程前沿（英文）》 2018年第12卷第4期页码 568-576 doi: 10.1007/s11709-017-0444-4

摘要： The study uses the finite element method to simulate a new technique of highway sand embankment filling in Jianghan Plain district, which can raise the thickness of sand-filled layer from 30 cm to 70 cm and can significantly shorten the construction period based on the guarantee of sand embankment construction quality. After simulating the three compacting proposals carried out on the field test, the study uses COMSOL software to research on the compacting effects of sand-filled layers in larger thicknesses by 22 ton vibratory roller alone, and then to investigate the steady compacting effect of 12 ton vibratory roller. The simulation results indicate that the sand-filled layer thickness of 70 cm is suitable for the new sand filling technique, and the sand-filled embankment project with tight construction period is suggested to choose the 12 ton vibration roller for steady compaction.

关键词： sand embankment compaction in large thickness numerical simulation small size vibratory roller steady compaction

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Optimizing environmental insulation thickness of buildings with CHP-based district heating system based

Yumei ZHANG, Pengfei JIE, Chunhua LIU, Jing LI

《能源前沿（英文）》 2022年第16卷第4期页码 613-628 doi: 10.1007/s11708-020-0700-5

摘要： The increase of insulation thickness (IT) results in the decrease of the heat demand and heat medium temperature. A mathematical model on the optimum environmental insulation thickness (OEIT) for minimizing the annual total environmental impact was established based on the amount of energy and energy grade reduction. Besides, a case study was conducted based on a residential community with a combined heat and power (CHP)-based district heating system (DHS) in Tianjin, China. Moreover, the effect of IT on heat demand, heat medium temperature, exhaust heat, extracted heat, coal consumption, carbon dioxide (CO ) emissions and sulfur dioxide (SO ) emissions as well as the effect of three types of insulation materials (i.e., expanded polystyrene, rock wool and glass wool) on the OEIT and minimum annual total environmental impact were studied. The results reveal that the optimization model can be used to determine the OEIT. When the OEIT of expanded polystyrene, rock wool and glass wool is used, the annual total environmental impact can be reduced by 84.563%, 83.211%, and 86.104%, respectively. It can be found that glass wool is more beneficial to the environment compared with expanded polystyrene and rock wool.

关键词： optimum environmental insulation thickness heat medium temperature energy grade extracted heat exhaust heat

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The ITZ microstructure, thickness, porosity and its relation with compressive and flexural strength of

《结构与土木工程前沿（英文）》页码 191-201 doi: 10.1007/s11709-021-0792-y

摘要： A new insight into the interfacial transition zone (ITZ) in cement mortar specimens (CMSs) that is influenced by cement fineness is reported. The importance of cement fineness in ITZ characterizations such as morphology and thickness is elucidated by backscattered electron images and by consequences to the compressive (F_c) and flexural strength (F_f), and porosity at various water/cement ratios. The findings indicate that by increasing the cement fineness the calcium silicate hydrate formation in the ITZ is favored and that this can refine the pore structures and create a denser and more homogeneous microstructure. By increasing cement fineness by about 25% of, the ITZ thickness of CMSs was reduced by about 30% and F_c was increased by 7%–52% and F_f by 19%–40%. These findings illustrate that the influence of ITZ features on the mechanical strength of CMSs is mostly related to the cement fineness and ITZ microstructure.

关键词： cement fineness interfacial transition zone compressive and flexural strength

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Eddy current measurement of the thickness of top Cu film of the multilayer interconnects in the integrated

Zilian QU,Yonggang MENG,Qian ZHAO

《机械工程前沿（英文）》 2015年第10卷第1期页码 1-6 doi: 10.1007/s11465-015-0325-2

摘要：

This paper proposes a new eddy current method, named equivalent unit method (EUM), for the thickness measurement of the top copper film of multilayer interconnects in the chemical mechanical polishing (CMP) process, which is an important step in the integrated circuit (IC) manufacturing. The influence of the underneath circuit layers on the eddy current is modeled and treated as an equivalent film thickness. By subtracting this equivalent film component, the accuracy of the thickness measurement of the top copper layer with an eddy current sensor is improved and the absolute error is 3 nm for sampler measurement.

关键词： CMP eddy current multilayer wafer Cu interconnects equivalent unit

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numerical studies on concrete encased trapezoidally web profiled cold formed steel beams by varying depth-thickness

Divahar RAVI, Aravind Raj PONSUBBIAH, Sangeetha Sreekumar PRABHA, Joanna Philip SARATHA

《结构与土木工程前沿（英文）》 2020年第14卷第4期页码 930-946 doi: 10.1007/s11709-020-0652-1

摘要： Concrete encased with trapezoidally corrugated web profiled cold-formed steel beams are used worldwide to improve resistance toward fire and corrosion, higher load carrying capacity as well as significant increase in the bending stiffness by encasing concrete on the beam portion. The present work gives a detailed description on the experimental, analytical and numerical investigation on the flexural behavior of concrete encased trapezoidally corrugated web profiled cold-formed steel beams which were simply supported at both ends and subjected to two point symmetric loading. The flexural behavior of such structure has been experimentally tested to failure under pure bending. To find the effect of concrete encasement in the web, 12 experiments were conducted by two different series. Beams having three different web corrugation angles of 0°, 30°, and 45° with two different web depth-thickness ( / ) ratios of 60 and 80 were tested. Experimental results such as load-deflection relationship, ultimate capacity, load-strain relationship, moment-curvature curves, ductility and failure mode indices of the specimens are presented. From the static bending tests the concrete encased trapezoidally corrugated web beam showed improved moment carrying capacity, ductility behavior and the resistance to transverse deflections in comparison to concrete encased with plain web beam. Especially for the beams with concrete encased 30° trapezoidally corrugated web having ( / ) ratio 60 and 80, the loading capacity was improved about 54% and 67.3% and the ductility also increased about 1.6 and 3.6 times, when compared to concrete encased beams with plain web. This research should contribute to the future engineering applications on seismic resistant structures and efficient usage of concrete encased with cold-formed steel beams by exhibiting its super elasto-plastic property. The analytical and numerical results showed good agreement with the experimental results at yield load, which indicates that the proposed analytical equations can be applied in predicting flexural strength accurately for such concrete encased trapezoidally corrugated web profiled cold-formed steel beams.

关键词： concrete encased beam trapezoidally corrugated web loading capacity super elasto-plastic

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Elastoplastic frictional contact problem study on interference fits of compressor

ZHANG Hongwu, WU Changhua, LIAO Aihua

《能源前沿（英文）》 2008年第2卷第3期页码 313-319 doi: 10.1007/s11708-008-0026-1

摘要： The FE parametric quadratic programming (PQP) method developed from the parametric variational principle (PVP) was used for the analysis of the stress distribution of the 3D elastoplastic frictional contact of an impeller-shaft sleeve-shaft. A locomotive-type turbocharger compressor with 24 blades under combined centrifugal and interference-fit loading was considered in the numerical analysis. The solution of elastoplastic frictional contact problems belongs to unspecified boundary problems where the interaction between two kinds of nonlinearities should occur. To save time in the numerical computation, a multi-substructure technique was adopted in the structural modeling. The effect of fit tolerance, wall thickness of the shaft sleeve, and rotational speed on the contact stress was discussed in detail in the numerical computation. To decrease the difficulty of the assembly process and ensure the safety of the working state, the amount of interference between the shaft sleeve and shaft by press-fitting should be controlled strictly to avoid the rapid increase of contact stress. The numerical results show that the algorithm has high accuracy and good convergence. The study can be referred to in deciding the proper fit tolerance and improving the design and manufacturing technology of compressor impellers.

关键词： computation thickness interference-fit interference unspecified

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The effects of interfacial strength on fractured microcapsule

Luthfi Muhammad MAULUDIN, Chahmi OUCIF

《结构与土木工程前沿（英文）》 2019年第13卷第2期页码 353-363 doi: 10.1007/s11709-018-0469-3

摘要： The effects of interfacial strength on fractured microcapsule are investigated numerically. The interaction between crack and microcapsule embedded in mortar matrix is modeled based on cohesive approach. The microcapsules are modelled with variation of core-shell thickness ratio and potential cracks are represented by pre-inserted cohesive elements along the element boundaries of the mortar matrix, microcapsules core, microcapsule shell, and at the interfaces between these phases. Special attention is given to the effects of cohesive fracture on the microcapsule interface, namely fracture strength, on the load carrying capacity and fracture probability of the microcapsule. The effect of fracture properties on microcapsule is found to be significant factor on the load carrying capacity and crack propagation characteristics. Regardless of core-shell thickness ratio of microcapsule, the load carrying capacity of self-healing material under tension increases as interfacial strength of microcapsule shell increases. In addition, given the fixed fracture strength of the interface of microcapsule shell, the higher the ratio core-shell thickness, the higher the probability of microcapsules being fractured.

关键词： interfacial strength cohesive elements microcapsule core-shell thickness ratio fracture properties

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深表土冻结壁变形规律

郭永富

《中国工程科学》 2011年第13卷第11期页码 81-88

摘要：

利用ANSYS软件建立数学模型，分析不同地压、不同冻结壁厚度、不同冻结壁平均温度、不同开挖段高与冻结壁变形之间的关系。通过研究发现,井帮位移随冻结壁平均温度的降低、冻结壁厚度的增大而减小，随施工段高增大、地层地压值的增大而增大，且地压值的变化对冻结壁的变形影响最为显著。据此提出了深表土冻结壁应按变形条件进行设计，且施工段高是影响冻结壁稳定性的极为重要的参数，在施工中应严格控制。研究提出当冻结壁厚度为10 m左右，平均温度达到－20 ℃时，采取降低冻结壁平均温度的方式比增加冻结壁厚度能更加有效地提高冻结壁的

关键词：井帮位移冻结壁厚度平均温度掘砌段高

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Numerical investigation on side heat transfer enhancement in 300 kA aluminum reduction cell

WANG Changhong, ZHU Dongsheng, LEI Junxi, ZHOU Jiemin

《能源前沿（英文）》 2008年第2卷第3期页码 256-260 doi: 10.1007/s11708-008-0051-0

摘要： Industrial test and numerical simulation were synchronously applied to analyze the side heat transfer process and enhance heat transfer in aluminum reduction cell. The 3D slice finite element model of aluminum reduction cell was developed, with which the sidewall temperature field of the cell was computed by using software ANSYS. The main influencing factors on heat dissipation were analyzed and some effective measures were proposed to enhance sidewall heat transfer. The results show that the shell temperature of the test cell and the common cell is respectively 312°C and 318°C and the ledge thickness is 16 cm and 15 cm when side coefficient of heat transfer between the shell and the surroundings is 70 W/(mK). With the increase of the side coefficient of heat transfer between the shell and the surroundings, the temperature of the shell decreases but the thickness of the side ledge increases when the electrolytic temperature, the ambient temperature, the coefficient of heat transfer between molten bath and ledge, the eutectic temperature and the thermo-resistance of the side lining are constant.

关键词： constant ambient temperature thickness electrolytic temperature transfer process

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Numerical simulation of liquid falling film on horizontal circular tubes

Fengdan SUN, Songlin XU, Yongchuan GAO

《化学科学与工程前沿（英文）》 2012年第6卷第3期页码 322-328 doi: 10.1007/s11705-012-1296-z

摘要： The objective of this study is to investigate numerically the flow characteristics of falling film on horizontal circular tubes. Numerical simulations are performed using FLUENT for 2D configurations with one and two cylinders. The volume of fluid method is used to track the motion of liquid falling film and the gas-liquid interface. The effect of flow characteristics on heat and transfer coefficient may be remarkable, although it has been neglected in previous studies. The velocity distribution and the film thickness characteristics on the top tube, some special flow characteristics on the bottom tube, intertube flow modes and effect of liquid feeder height on flow characteristics have been studied. Our simulations indicate that 1) the velocity distributions of the upper and lower parts of the tube are not strictly symmetric and non-uniform, 2) the film thickness depends on flow rate and angular distributions, 3) the flow characteristics of the top tube are different from those of the bottom tube, 4) three principal and two intermediate transition modes are distinguished, and 5) the liquid feed height plays an important role on the formation of falling film. The numerical results are in a good agreement with the theoretical values by the Nusselt model and the reported results.

关键词： falling film horizontal tube flow characteristics film thickness liquid feeder height

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标题作者时间类型操作

Genome-wide association study of the backfat thickness trait in two pig populations

Dandan ZHU,Xiaolei LIU,Rothschild MAX,Zhiwu ZHANG,Shuhong ZHAO,Bin FAN

期刊论文

Effects of sheet thickness and material on the mechanical properties of flat clinched joint

Chao CHEN, Huiyang ZHANG, Shengdun ZHAO, Xiaoqiang REN

期刊论文

Lamellar thickness transition of melt-crystallized polybuten-1 tetragonal phase: configurational change

Motoi YAMASHITA

期刊论文

Determining the optimum economic insulation thickness of double pipes buried in the soil for district

Fating LI, Pengfei JIE, Zhou FANG, Zhimei WEN

期刊论文

Modeling of the minimum cutting thickness in micro cutting with consideration of the friction around

Tianfeng ZHOU, Ying WANG, Benshuai RUAN, Zhiqiang LIANG, Xibin WANG

期刊论文

Numerical simulation of compaction parameters for sand-filled embankment using large thickness sand filling

Wentao WANG, Chongzhi TU, Rong LUO

期刊论文

Optimizing environmental insulation thickness of buildings with CHP-based district heating system based

Yumei ZHANG, Pengfei JIE, Chunhua LIU, Jing LI

期刊论文

The ITZ microstructure, thickness, porosity and its relation with compressive and flexural strength of

期刊论文

Eddy current measurement of the thickness of top Cu film of the multilayer interconnects in the integrated

Zilian QU,Yonggang MENG,Qian ZHAO

期刊论文

numerical studies on concrete encased trapezoidally web profiled cold formed steel beams by varying depth-thickness

Divahar RAVI, Aravind Raj PONSUBBIAH, Sangeetha Sreekumar PRABHA, Joanna Philip SARATHA

期刊论文

Elastoplastic frictional contact problem study on interference fits of compressor

ZHANG Hongwu, WU Changhua, LIAO Aihua

期刊论文

The effects of interfacial strength on fractured microcapsule

Luthfi Muhammad MAULUDIN, Chahmi OUCIF

期刊论文

深表土冻结壁变形规律

郭永富

期刊论文

Numerical investigation on side heat transfer enhancement in 300 kA aluminum reduction cell

WANG Changhong, ZHU Dongsheng, LEI Junxi, ZHOU Jiemin

期刊论文

Numerical simulation of liquid falling film on horizontal circular tubes

Fengdan SUN, Songlin XU, Yongchuan GAO

期刊论文

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