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New Protocol for Orientation Reconstruction from Martensite to Austenite in Steels 钢中马氏体向奥氏体取向重建的新方法
Pub Date : 2019-06-19 DOI: 10.2139/ssrn.3406399
Cheng-Yao Huang, H. Ni, H. Yen
Abstract This work presents an approach for reconstructing the orientation of prior austenite using the martensite crystallography from an electron backscatter diffraction dataset. To optimize the accuracy and speed of reconstruction, the algorithm comprises three steps: orientation relationship refinement, orientation coalescence, and regional voting. Martensitic stainless steels with/without retained austenite were used to demonstrate this approach. The reconstruction parameters can be determined theoretically or semi-theoretically in this algorithm. Moreover, mis-indexing near the twinning boundaries of prior austenite is minimized in the regional voting process. Although some issues remain unsolved, this approach provides a balance between accuracy and efficiency in austenite reconstruction.
摘要本文提出了一种利用电子背散射衍射数据集的马氏体晶体学重建先前奥氏体取向的方法。为了优化重建的精度和速度,该算法分为三个步骤:方向关系细化、方向合并和区域投票。用带有/不带有残余奥氏体的马氏体不锈钢来证明这种方法。该算法可以从理论上或半理论上确定重建参数。此外,在区域投票过程中,在先验奥氏体的孪生边界附近的错误索引被最小化。虽然有些问题尚未解决,但该方法在奥氏体重建中提供了精度和效率之间的平衡。
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引用次数: 29
Thermodynamic Origin of Solute-Enriched Stacking-Fault in Dilute Mg-Zn-Y Alloys 稀Mg-Zn-Y合金富溶质堆积断层的热力学成因
Pub Date : 2019-06-12 DOI: 10.2139/ssrn.3411750
M. Egami, I. Ohnuma, M. Enoki, H. Ohtani, E. Abe
We investigate thermodynamic behaviors of dilute Mg-Zn-Y ternary alloys to form a unique solute-enriched stacking-fault (SESF), which is an intrinsic-II type stacking-fault (I2-SF) enriched by the Zn and Y atoms and represents the structural-unit of the long-period stacking/order (LPSO) phase. SESF in the hexagonal-close-packed (hcp) Mg matrix forms a local face-centered-cubic (fcc) environment, and hence our thermodynamic analysis is based on the Gibbs energy comparison between hcp and fcc phases over the Mg-Zn-Y ternary composition ranges, using the calculation of phase diagrams (CALPHAD) method aided by the first principles calculations. Segregation behaviors of solute Zn/Y atoms into the SESF are firstly estimated according to the Hillert's parallel tangent law, followed by the possible disorder-order phase transformation within the SESF using the multiple-sublattice model. We find that the Zn/Y co-segregations at the SESF provide a remarkable condition that the fcc layers become more stable than the hcp-Mg matrix. Besides, within the SESF, the following spinodal-like decomposition into the Mg-rich solid-solution and the Zn/Y-rich L12-type order phase causes a significant reduction of the total Gibbs energy of the system. These thermodynamic behaviors explain fairly well a phenomenological origin of the Zn-Y clustering with the L12-type short-range order, which is known to occur for the LPSO phases and also confirmed for the present SESF by electron microscopy experiments. Therefore, strong Zn-Y interactions even in dilute conditions play a key role to stabilize firmly the SESF in the Mg-Zn-Y alloys.
本文研究了稀Mg-Zn-Y三元合金形成独特的富溶质堆积断层(SESF)的热力学行为,这是一种由Zn和Y原子富集的本征ii型堆积断层(I2-SF),代表了长周期堆积/有序(LPSO)相的结构单元。六边形密填料(hcp) Mg基体中的SESF形成了局部面心立方(fcc)环境,因此我们的热力学分析是基于在Mg- zn - y三元组成范围内hcp相和fcc相之间的吉布斯能量比较,使用相图计算(CALPHAD)方法辅助第一性原理计算。首先根据Hillert平行切线定律估计了溶质Zn/Y原子在SESF中的偏析行为,然后利用多亚晶格模型估计了SESF内可能发生的无序-有序相变。我们发现在SESF中Zn/Y的共偏析为fcc层比hcp-Mg基体更稳定提供了一个显著的条件。此外,在SESF内,随后的spinodal样分解为富mg固溶体和富Zn/ y的l12型有序相,导致体系的总吉布斯能量显著降低。这些热力学行为很好地解释了l12型短程有序的Zn-Y聚类的现象学起源,这种现象已知发生在LPSO相中,并且通过电子显微镜实验也证实了目前的SESF。因此,即使在稀释条件下,强Zn-Y相互作用也对稳定Mg-Zn-Y合金中的SESF起着关键作用。
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引用次数: 18
ปัจจัยที่มีอิทธิพลต่อผลสัมฤทธ์ิของการบริหารจัดการสหกรณ์ที่มีโรงงานแปรรูปยางพาราผ่านการรับรองมาตรฐานระบบการปฏิบัติและจัดการคุณภาพที่ดี (Factors Affecting the Achievement of GMP Certified Rubber Plantation Fund Co-Operative) ปัจจัยที่มีอิทธิพลต่อผลสัมฤทธ์ิของการบริหารจัดการสหกรณ์ที่มีโรงงานแปรรูปยางพาราผ่านการรับรองมาตรฐานระบบการปฏิบัติและจัดการคุณภาพที่ดี(影响因素实现GMP认证的橡胶种植园基金合作)
Pub Date : 2019-06-01 DOI: 10.2139/ssrn.3461567
Pheeraphan Haemarat
Thai Abstract: การวิจัยครั้งนี้มีวัตถุประสงค์เพื่อ 1) ศึกษาระดับผลสัมฤทธิ์ ของการบริหารจัดการ 2) ศึกษาระดับปัจจัยของการบริหารจัดการ3)ศึกษาปัจจัยที่มีอิทธิพลต่อผลสัมฤทธิข์ องการบริหารจัดการ และ 4) เสนอแนะตัวแบบการพัฒนาสหกรณ์กองทุนสวนยางที่มีโรงงานแปรรูปยางพาราผ่านการรับรองมาตรฐานระบบการปฏิบัติและจัดการคุณภาพที่ดี ในงานวิจัยฉบับนี้ ใช้แนวคิดเกี่ยวกับผลสัมฤทธิโ์ ดยสังเคราะห์ออกมาได้ 3 ด้าน ประกอบด้วย 1) ความประหยัด 2) ความมีประสิทธิภาพ และ 3) ความมี เป็นการวิจัยแบบผสานวิธี ทั้งเชิงปริมาณและเชิงคุณภาพ การวิจัยเชิงปริมาณดา เนินการโดยผู้ตอบแบบสอบถาม จา นวน 367 คน จากจา นวนประชากร 7,589 คน ซึ่งเลือกจากสมาชิกสหกรณ์และกลุ่มเกษตรกรที่มีโรงงานแปรรูปยางพาราผ่านการรับรองมาตรฐานระบบการปฏิบัติและจัดการคุณภาพที่ดี ส่วนการวิจัยเชิงคุณภาพ ดาเนินการโดยการสัมภาษณ์เชิงลึก โดยมีผู้ให้ข้อมูลสาจานวน 15 คน ผลการวิจัยพบว่าระดับผลสัมฤทธิ์ ของการบริหารจัดการระดับปัจจัยและปัจจัยที่มีอิทธิพลต่อผลสัมฤทธิข์ องการบริหารจัดการโรงงานแปรรูปยางพาราของสหกรณ์กองทุนสวนที่ผ่านการรับรองมาตรฐานระบบการปฏิบัติและจัดการ, คุณภาพที่ดี ตัวแบบการพัฒนาสหกรณ์กองทุนสวนยางที่มีโรงงานแปรรูปยางพาราผ่านการรับรองมาตรฐานระบบการปฏิบัติและจัดการคุณภาพที่ดีประกอบด้วย 1) ผู้นา กรรมการ และฝ่ายจัดการ 2) การมีส่วนร่วมของสมาชิก 3) เงินทุนเพียงพอ 4)กระบวนการที่ได้มาตรฐาน 5) การตลาดและลูกค้า

English Abstract: This study has the objectives of 1) to study the characteristics of Good Manufacturing Practices (GMP) certified rubber processing plants of Rubber Plantation Fund Cooperatives, 2) to study the achievement of Good Manufacturing Practices (GMP) certified rubber processing plants of Rubber Plantation Fund Cooperatives with standard manufacturing process and quality management, 3) to study the factors affecting achievements of Good Manufacturing Practices (GMP) certified rubber processing plants of Rubber Plantation Fund Cooperatives, 4) to study the problems, obstacles, and recommendations for the management of Good Manufacturing Practices (GMP) certified rubber processing plants of Rubber Plantation Fund Cooperatives, and 5) to recommend model to improve manufacturing process and quality management of Good Manufacturing Practices (GMP) certified rubber processing plants of Rubber Plantation Fund Cooperatives. The achievement of Good Manufacturing Practices (GMP) mean the practice of organization which follow the activity that result on Outcome as a result of outputs in activity. The effectiveness has depended on critical success factors (CSR) which is important to achieve objective of all KPI. We analyze into 1) Economy 2) Efficiency 3) Effectiveness. This study is a mixed methodology using both quantitative and qualitative research. The quantitative research employed survey method conducted on 367 samples from the total population of 7,589 members of Good Manufacturing Practices (GMP) certified rubber processing plants of Rubber Plantation Fund Cooperatives. The qualitative study used in-depth interview with 15 key informants who were cooperative managers and experts, who were selected us
泰语:本研究的目的是:1)研究管理效果的影响程度;2)研究管理效果的影响因素;4)通过标准化、实用和高质量的方法来研究发展的建议。这项量化研究由75,89名人口的367名受访者进行。通过标准认证、操作系统和质量管理,通过深入的访谈,进行了高质量的研究。该研究发现,通过标准、操作和管理系统认证的橡胶种植园基金,具有良好的质量发展模式,通过标准、操作和管理系统认证的橡胶种植园基金,2)会员参与,4)标准流程,5)市场和客户满意度。2)标准化处理标准化处理标准化处理标准化处理标准化处理标准化处理标准化处理。3)到标准化处理标准化处理,4)到标准化处理。5)到最佳工艺处理和质量处理。1) Economy 2) effect .这是一种混合二元性的方法。无论如何,我们都将选择与我们的方法相关联。
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引用次数: 0
Fabrication of Multipurpose Agricultural Tiller 多功能农用分蘖机的研制
Pub Date : 2019-05-17 DOI: 10.2139/ssrn.3507973
Sai Vinay M. R., A. G, Vinod. K.V, Vikas Noolkar, K. R
The main objective of the project is development and fabrication of a multipurpose agricultural tiller which will perform a wide range of operations such as rotary, ploughing, seeding, pesticide spraying, harvesting, weeding at a reasonable cost to overcome the challenges faced by the farmer. The multipurpose agricultural tiller has been fabricated on a rigid chassis frame which holds a universal shaft on which rotary and wheels can be mounted. This universal shaft derives 8 BHP of power from a 4-Stroke IC engine placed firmly on the chassis frame. The mechanism used is such that the same engine drives the wheels, rotavator, harvester, pesticide sprayer, seeder, leaver, plough and trolley. The reciprocating motion provided to the harvester cuts the crop precisely, consuming less time as compared to conventional techniques of harvesting. A power sprayer is used which will facilitate spraying of pesticide at different heights of crop cultivation. A multi-way adjustable plough is also used whose position can be adjusted on a slide through frame according to the requirement of the farmer. A multi variety seeding operation is also setup. Multipurpose agricultural tiller can be easily afforded by average and marginal class of farmers.
该项目的主要目标是开发和制造一种多用途农业播种机,它将以合理的成本执行广泛的操作,如旋转、犁地、播种、喷洒农药、收获、除草,以克服农民面临的挑战。该多用途农用分蘖已被制造在刚性底盘框架上,该底盘框架持有可安装在其上的旋转和车轮的通用轴。这个通用轴从一个4冲程集成电路发动机牢牢地放在底盘框架上获得8马力的动力。所使用的机械装置是由同一台发动机驱动轮子、旋转机、收割机、农药喷雾器、播种机、除草机、犁和小车。提供给收割机的往复运动精确地切割作物,与传统的收割技术相比,消耗更少的时间。采用动力喷雾器,方便在作物种植的不同高度喷洒农药。还采用了多路可调犁,其位置可根据农民的要求在滑架上调整。还建立了多品种播种操作。普通和边缘阶层的农民可以很容易地负担得起多用途农业耕作机。
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引用次数: 0
Parametric Optimization in Machining of Hybrid MMCs – A Review 混合mmc加工中的参数优化研究综述
Pub Date : 2019-05-17 DOI: 10.2139/ssrn.3507966
N. H., N. Chikkanna, Kushal N., K. M.
Metal Matrix Composites represents a category of substances that have giant applications because of their customizable choice within the preparation which results in changing properties which could have numerous applications based totally on the tailor made properties. Although we can find the various applications of MMCs it is a really hectic and tough task for any individual to forecast the exact parametric combination of machining them.  An attempt is made by the researchers to gather and conclude the statement of better parametric combination in machining of MMCS has been made several times. Many procedural observations along with the results are described considering many mathematical, scientifical and statistical models build to analyze the effects of various parametric combination altogether. This paper focuses on the assessment made by using literature associated with the topic selected.
金属基复合材料代表了一类具有巨大应用的物质,因为它们可以在制备过程中进行可定制的选择,从而改变性能,从而完全基于定制的性能可以有许多应用。虽然我们可以找到mmc的各种应用,但对于任何个人来说,预测加工它们的确切参数组合是一项非常忙碌和艰巨的任务。研究人员多次尝试收集和总结MMCS加工中较好的参数组合的说法。考虑到为分析各种参数组合的影响而建立的许多数学、科学和统计模型,描述了许多程序观察结果。本文的重点是利用与所选主题相关的文献进行评估。
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引用次数: 0
Case Studies on Sustainable Soil Health Management Through Application of Organic Amendments in Dolichos Bean Cultivation 应用有机改良剂对豆栽培土壤可持续健康管理的案例研究
Pub Date : 2019-05-17 DOI: 10.2139/ssrn.3511437
M. S., H. K.
The experiment was conducted to standardize the quantity of bulky and concentrated organic manures for Dolichos Bean to substitute the inorganic fertilizers. The experiment was laid out in a randomized block design with 14 treatments in 3 replications. The treatment schedule included various levels of bulky (25 and 75 % N) and concentrated organic manures (25 and 75 % N), inorganic fertilizers along with an absolute control. The bulky organic manures used were FYM and vermicompost and the concentrated manures used were neem cake and groundnut cake. The nutrient content of bulky and concentrated organic manures used in the study were FYM (0.80, 0.41 and 0.74 % NPK), vermicompost (1.60, 2.20 and 0.67 % NPK), poultry manure (3.47, 1.33 and 3.1 NPK), neem cake (5.2, 1.0 and 1.4 % NPK) and castor cake (4.1, 1.9 and 1.4 % NPK). Quantity of organic manures required was computed on the basis of nitrogen equivalent to substitute the recommended dose of chemical fertilizer (32:72 kg NP ha-1) in garden bean.Among the organic manures and concentrated oil cakes applied, 75 per cent N supplied through vermicompost @ 2.41 t ha-1 along with 25 per cent N supplied through neem cake @ 0.22 t ha-1 followed by 75 percent N supplied through poultry manure @ 0.61 t ha-1 along with neem cake @ 0.22 t ha-1 were identified.Which recorded the maximum level of soil physico-chemical properties, number of,nutrient uptake ,post harvest nutrient status of soil and yield of Garden bean.
本试验旨在规范豆科作物块状、浓缩有机肥替代无机肥的用量。试验采用随机区组设计,14个处理,3个重复。处理计划包括不同水平的肥肥(25%和75% N)和浓缩有机肥料(25%和75% N),无机肥料以及绝对控制。施用的有机肥主要为有机肥和蚯蚓堆肥,施用的浓缩有机肥主要为印楝饼和花生饼。本研究使用的块状和浓缩有机肥料的营养成分含量分别为:FYM(0.80、0.41和0.74%氮磷钾)、蚯蚓堆肥(1.60、2.20和0.67%氮磷钾)、禽粪(3.47、1.33和3.1氮磷钾)、印米饼(5.2、1.0和1.4%氮磷钾)和蓖麻饼(4.1、1.9和1.4%氮磷钾)。以氮肥当量为基础计算有机肥需要量,以替代菜豆化肥推荐用量(32:72 kg NP ha-1)。在施用有机肥和浓缩油饼中,75%的氮素通过蚯蚓堆肥提供,@ 2.41 t hm -1, 25%的氮素通过印楝饼提供,@ 0.22 t hm -1, 75%的氮素通过禽粪提供,@ 0.61 t hm -1, @ 0.22 t hm -1。记录了菜豆的土壤理化性质、数量、养分吸收量、采后土壤养分状况和产量的最高水平。
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引用次数: 0
Application of Bottles as a Sustainable Material in Building Construction 瓶子作为可持续材料在建筑施工中的应用
Pub Date : 2019-04-28 DOI: 10.2139/ssrn.3379190
Akshaykumar Raut
The cost of construction in building the world house is important factor in field of construction. It depends upon the individual requirements and if people are below poverty line then it is difficult for them. Also the increase in urbanization has developed the non-renewable products like plastic bottle. This products can be used in construction. So that the Eco-friendly construction can be done forming the suitable thermal resistance to structure. Plastic bottles are generally used to store different material for consumption and for many other uses. When bottles are incinerated the huge amount of toxic fume are produced which are harmful to nature. Recycling is only survival option because only PET bottles can be recycled all other bottles are discarded and only 1 out of 5 bottles are sent to the recycle bin. So this tends to need for constructive use of waste plastic bottles in environment friendly way. This paper consist of use of plastic bottle as sustainable material i.e. as a substance similar to brick in nature, which is filled with compacted sand, fly ash and combination of both, different testing on them comparative to bricks and economic advantages over the traditional brick so that idea of safe and Ecofriendly construction can be incorporated and a wise step towards environment saving can be take place.
世界住宅的建造成本是建筑领域的一个重要因素。这取决于个人需求,如果人们在贫困线以下,那么他们就很难。此外,城市化的增加也开发了不可再生的产品,如塑料瓶。本产品可用于建筑施工。从而形成适宜的结构热阻,实现环保建筑。塑料瓶通常用来储存不同的消费材料和许多其他用途。当瓶子被焚烧时,会产生大量有害于自然的有毒烟雾。回收是唯一的生存选择,因为只有PET瓶可以回收,所有其他的瓶子被丢弃,只有1 / 5的瓶子被送到回收站。因此,这往往需要以环保的方式建设性地利用废旧塑料瓶。本文包括使用塑料瓶作为可持续材料,即作为一种性质类似于砖的物质,它填充了压实的沙子,粉煤灰和两者的组合,对它们进行了不同的测试,与砖相比,与传统砖相比具有经济优势,因此可以纳入安全和环保建筑的理念,并朝着节约环境迈出明智的一步。
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引用次数: 2
CFD Modeling and Simulation of Oil-Water Flows in Oil Reservoir 油层油水流动的CFD建模与模拟
Pub Date : 2019-04-28 DOI: 10.2139/ssrn.3371766
Rachida Chemini, M. Aksouh, Bassim Lemouari, Soumana Abubacar Djibo
Understanding fluid flow in porous media is of tremendous importance for many industrial and environmental applications at various spatial and temporal scales. The present study consequently focuses on CFD 2D modeling of single-phase flow in steady mode, and unsteady mode oil-water flows by the Volume-of-Fluid method (VOF) in oil reservoir using ANSYS Fluent while meshing has been done on Gambit. The effects of temperature and permeability on water flow in porous medium, which was considered as a reservoir have been studied in this work, velocity and pressure distributions, also have been presented. In oil-water flow simulation, total pressure and oil volume fraction distributions have been visualized. Besides, the study of pressure gradient and permeability effects on the breakthrough time and on the recoverable oil has been carried out.
了解多孔介质中的流体流动对于许多工业和环境应用在不同的空间和时间尺度上是非常重要的。因此,本文的研究重点是在Gambit上进行网格划分的同时,利用ANSYS Fluent对稳态模式下的单相流动和非稳态模式下的油水流动进行CFD二维建模。本文研究了温度和渗透率对多孔介质中水流的影响,并给出了速度和压力的分布。在油水流动模拟中,总压和油体积分数的分布已经可视化。此外,还研究了压力梯度和渗透率对突破时间和可采原油的影响。
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引用次数: 0
Double-Difffusive Natural Convection of TiO2-Water Nanofluid in a Square Cavity 二氧化钛-水纳米流体在方形腔中的双扩散自然对流
Pub Date : 2019-04-19 DOI: 10.2139/ssrn.3373790
Nihal Toudja, N. Labsi, Y. K. Benkahla, Seif-Eddine Ouyahia, Mahdi Benzema
Natural convection heat and mass transfer in a square cavity is numerically studied in the present paper. The cavity is filled with a water-based nanofluid containing TiO2 nanoparticles. The governing equations are solved numerically using the finite volume method. The velocity-pressure coupling is achieved using the SIMPLER algorithm. This study focuses on the effect of some parameters, namely, the Rayleigh number and the nanoparticles volume fraction on the flow pattern as well as on heat and mass transfer.
本文对方形腔内的自然对流传热传质进行了数值研究。空腔被含有TiO2纳米颗粒的水基纳米流体填充。采用有限体积法对控制方程进行了数值求解。采用更简单的算法实现速度-压力耦合。本文主要研究了瑞利数和纳米颗粒体积分数等参数对流动型和传热传质的影响。
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引用次数: 0
Design and Fabrication of Multi Nut Opener and Tightener 多螺母开紧器的设计与制造
Pub Date : 2019-04-16 DOI: 10.2139/ssrn.3372737
Rahul Samre, Arif Khan, Shubham Jhunjhune, Surendra Sawner, Singh Dangi Yashpal
This project aim is to design and fabrication of Multi Nut Opener and tightener for tightening and removing of four nuts altogether. With the increment of number of car on the road, the number of cars problem due to tyre failure has increased. Often, the car is provided with tyre wheel nuts remover and jack for instance spare tyre replacement. Nevertheless, due to difficulty in applying torque to remove nut and to save a time. We develop tool having a gear mechanism. In our project we are tried to focus on the minimization of human effort for fixing all for nuts of 100mm PCD wheel . The main objective of work is to develop a single tool, which can be made use during assembling and disassembling of wheels in automobiles. It can be successfully used as standard tool irrespective of the model of the vehicle. Also it can be used garages, workshops and service stations. The remover is designed to be ergonomic to be used, easy maintenance, easy storage, easy to handled and able to remove all nuts at once.
本设计的目的是设计和制造一种多螺母开扣器,用于同时拧紧和拆卸四个螺母。随着道路上汽车数量的增加,因轮胎故障引起的汽车问题也越来越多。通常,汽车配有轮胎螺母拆卸器和千斤顶,例如备用轮胎更换。然而,由于难以施加扭矩来拆卸螺母并节省时间。我们开发有齿轮机构的工具。在我们的项目中,我们试图专注于将人力最小化,以固定100mm PCD轮的所有螺母。工作的主要目标是开发一种可以在汽车车轮的组装和拆卸过程中使用的单一工具。无论车辆的型号如何,它都可以成功地作为标准工具使用。也可用于车库、车间和服务站。该去除器设计符合人体工程学,易于维护,易于储存,易于处理,能够一次去除所有螺母。
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引用次数: 0
期刊
MatSciRN: Other Materials Processing & Manufacturing (Topic)
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