This collection includes most of the ASU Theses and Dissertations from 2011 to present. ASU Theses and Dissertations are available in downloadable PDF format; however, a small percentage of items are under embargo. Information about the dissertations/theses includes degree information, committee members, an abstract, supporting data or media.

In addition to the electronic theses found in the ASU Digital Repository, ASU Theses and Dissertations can be found in the ASU Library Catalog.

Dissertations and Theses granted by Arizona State University are archived and made available through a joint effort of the ASU Graduate College and the ASU Libraries. For more information or questions about this collection contact or visit the Digital Repository ETD Library Guide or contact the ASU Graduate College at gradformat@asu.edu.

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Description
University graduates play a significant role in the labor market of China. Universities continuously supply senior talents and provide a strong guarantee to the country’s development. However, with the enlargement of the enrollment scale, more and more graduates become unemployed or forced to be employed. Most literatures mainly focus on

University graduates play a significant role in the labor market of China. Universities continuously supply senior talents and provide a strong guarantee to the country’s development. However, with the enlargement of the enrollment scale, more and more graduates become unemployed or forced to be employed. Most literatures mainly focus on the unemployed phenomenon or reasons, but had neglected the relationship among the employment, universities and the labor market. This assay is trying to using the supply and demand theory of classical economics to analyze the training direction and model of university from the perspective of the supply and demand of labor market. This assay proposes that universities have to integrate with the demand of the labor market so that to cultivate the talents to meet the social needs.

Firstly, the essay analyzes the relationship between the universities education and the supply and demand labor market by using the view of labor economics, and shows the mainly phenomenon and features of supply-demand imbalance. And then, the writer considered that universities talent cultivation development of China has gone through “absolute shortage”, “relative shortage” and “structural unbalanced” three stages. Thirdly, the survey results confirmed that the talent cultivation in universities does not match the demand of the labor market. On one other hand, over educated is a common phenomenon in the academic education. On the other hand, the graduates are lack of education skills training. Fourthly, the essay analyzes the reasons which lead to the unbalance. The unbalance is not only affected by the macro factors, but also by the micro factors. Fifthly, build up the interaction system model “UPT-LM” for the universities talent cultivation and the labor market, and separately building up the macro interaction system and the micro interaction system to analyze the balance of supply and demand. Based on this, it should strengthen the interaction on the feedback mechanism. At last, strengthening the connection of universities talent cultivation and labor market is a systematic program which needs the corporation from the government, the universities and the labor market.
ContributorsLin, Xiaoya (Author) / Shen, Wei (Thesis advisor) / Qian, Jun (Thesis advisor) / Li, Feng (Committee member) / Arizona State University (Publisher)
Created2017
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Description
A comprehensive and systematic investigation on the diffusion and phase behaviors of nanoparticles and macromolecules in two component liquid-liquid systems via Molecule Dynamic (MD) simulations is presented in this dissertation.

The interface of biphasic liquid systems has attracted great attention because it offers a simple, flexible, and highly reproducible template for

A comprehensive and systematic investigation on the diffusion and phase behaviors of nanoparticles and macromolecules in two component liquid-liquid systems via Molecule Dynamic (MD) simulations is presented in this dissertation.

The interface of biphasic liquid systems has attracted great attention because it offers a simple, flexible, and highly reproducible template for the assembly of a variety of nanoscale objects. However, certain important fundamental issues at the interface have not been fully explored, especially when the size of the object is comparable with the liquid molecules. In the first MD simulation system, the diffusion and self-assembly of nanoparticles with different size, shape and surface composition were studied in an oil/water system. It has been found that a highly symmetrical nanoparticle with uniform surface (e.g. buckyball) can lead to a better-defined solvation shell which makes the “effective radius” of the nanoparticle larger than its own radius, and thus, lead to slower transport (diffusion) of the nanoparticles across the oil-water interface. Poly(N-isopropylacrylamide) (PNIPAM) is a thermoresponsive polymer with a Lower Critical Solution Temperature (LCST) of 32°C in pure water. It is one of the most widely studied stimulus-responsive polymers which can be fabricated into various forms of smart materials. However, current understanding about the diffusive and phase behaviors of PNIPAM in ionic liquids/water system is very limited. Therefore, two biphasic water-ionic liquids (ILs) systems were created to investigate the interfacial behavior of PNIPAM in such unique liquid-liquid interface. It was found the phase preference of PNIPAM below/above its LCST is dependent on the nature of ionic liquids. This potentially allows us to manipulate the interfacial behavior of macromolecules by tuning the properties of ionic liquids and minimizing the need for expensive polymer functionalization. In addition, to seek a more comprehensive understanding of the effects of ionic liquids on the phase behavior of PNIPAM, PNIPAM was studied in two miscible ionic liquids/water systems. The thermodynamic origin causes the reduction of LCST of PNIPAM in imidazolium based ionic liquids/water system was found. Energy analysis, hydrogen boding calculation and detailed structural quantification were presented in this study to support the conclusions.
ContributorsGao, Wei (Author) / Dai, Lenore (Thesis advisor) / Jiao, Yang (Committee member) / Liu, Yongming (Committee member) / Green, Matthew (Committee member) / Emady, Heather (Committee member) / Arizona State University (Publisher)
Created2017
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Description
The Very High Temperature Reactor (VHTR) is one of six conceptual designs proposed for Generation IV nuclear reactors. Alloy 617, a solid solution strengthened Ni-base superalloy, is currently the primary candidate material for the tubing of the Intermediate Heat Exchanger (IHX) in the VHTR design. Steady-state operation of the nuclear

The Very High Temperature Reactor (VHTR) is one of six conceptual designs proposed for Generation IV nuclear reactors. Alloy 617, a solid solution strengthened Ni-base superalloy, is currently the primary candidate material for the tubing of the Intermediate Heat Exchanger (IHX) in the VHTR design. Steady-state operation of the nuclear power plant at elevated temperatures leads to creep deformation, whereas loading transients including startup and shutdown generate fatigue. A detailed understanding of the creep-fatigue interaction in Alloy 617 is necessary before it can be considered as a material for nuclear construction in ASME Boiler and Pressure Vessel Code. Current design codes for components undergoing creep-fatigue interaction at elevated temperatures require creep-fatigue testing data covering the entire range from fatigue-dominant to creep-dominant loading. Classical strain-controlled tests, which produce stress relaxation during the hold period, show a saturation in cycle life with increasing hold periods due to the rapid stress-relaxation of Alloy 617 at high temperatures. Therefore, applying longer hold time in these tests cannot generate creep-dominated failure. In this study, uniaxial isothermal creep-fatigue tests with non-traditional loading waveforms were designed and performed at 850 and 950°C, with an objective of generating test data in the creep-dominant regime. The new loading waveforms are hybrid strain-controlled and force-controlled testing which avoid stress relaxation during the creep hold. The experimental data showed varying proportions of creep and fatigue damage, and provided evidence for the inadequacy of the widely-used time fraction rule for estimating creep damage under creep-fatigue conditions. Micro-scale damage features in failed test specimens, such as fatigue cracks and creep voids, were quantified using a Scanning Electron Microscope (SEM) to find a correlation between creep and fatigue damage. Quantitative statistical imaging analysis showed that the microstructural damage features (cracks and voids) are correlated with a new mechanical driving force parameter. The results from this image-based damage analysis were used to develop a phenomenological life-prediction methodology called the effective time fraction approach. Finally, the constitutive creep-fatigue response of the material at 950°C was modeled using a unified viscoplastic model coupled with a damage accumulation model. The simulation results were used to validate an energy-based constitutive life-prediction model, as a mechanistic model for potential component and structure level creep-fatigue analysis.
ContributorsTahir, Fraaz (Author) / Liu, Yongming (Thesis advisor) / Jiang, Hanqing (Committee member) / Rajagopalan, Jagannathan (Committee member) / Oswald, Jay (Committee member) / Jiao, Yang (Committee member) / Arizona State University (Publisher)
Created2017
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Description
After the 2008 financial crisis, along with information technology and its application

innovation into the burst period, Shared faster economic growth, and then entered into a

rapid expansion in 2014, quickly penetrate into many areas and market segments.

As the securities industry practitioners and Internet financial practitioners, I am

very concerned about sharing economic

After the 2008 financial crisis, along with information technology and its application

innovation into the burst period, Shared faster economic growth, and then entered into a

rapid expansion in 2014, quickly penetrate into many areas and market segments.

As the securities industry practitioners and Internet financial practitioners, I am

very concerned about sharing economic model in the development of securities

investment niche. As the Internet and mobile penetration rate rise in recent years, the

Internet financial in the rapid development of our country, investors get used for

investment decision-making information via the Internet. Internet social investment

sharing platform based on knowledge sharing and rapid development, has formed

"opinion leaders", "combined with", "automated financial innovation model". The

emergence of these new patterns, provide investors with investment of knowledge sharing,

the investors behavior changes, many small and medium-sized investors into social

sharing platform for the combination of investment talent information and follow orders,

and centered on investment talent view form fan interaction.

This article around the "Shared economic environment on the impact of portfolio

share on investor behavior research," the theme, the relevant literature and resources, and

to detect Shared economic environment provided by the social share portfolio, whether to

change the traditional information decision and disadvantages of small and medium-sized

investors, whether really improved the small and medium-sized investors return on

investment, its conclusion try to explain the traditional period research literature on active

investment and passive investment, the relevant conclusions of small and medium-sized

investors and institutional investors, sharing in the Internet the rapid development of

economic period is changed.
ContributorsMa, Gang (Author) / Gu, Bin (Thesis advisor) / Yan, Hong (Thesis advisor) / Shen, Wei (Committee member) / Arizona State University (Publisher)
Created2017
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Description
Over the past several years, the density of integrated circuits has been increasing at a very fast rate, following Moore’s law. The advent of three dimensional (3D) packaging technologies enable the increase in density of integrated circuits without necessarily shrinking the dimensions of the device. Under such constraints, the solder

Over the past several years, the density of integrated circuits has been increasing at a very fast rate, following Moore’s law. The advent of three dimensional (3D) packaging technologies enable the increase in density of integrated circuits without necessarily shrinking the dimensions of the device. Under such constraints, the solder volume necessary to join the various layers of the package is also extremely small. At smaller length scales, the local cooling rates are higher, so the microstructures are much finer than that obtained in larger joints (BGA, C4). The fraction of intermetallic compounds (IMCs) present in solder joints in these volumes will be larger. The Cu6Sn5 precipitate size and spacing, and Sn grain structure and crystallography will be different at very small volumes. These factors will most certainly affect the performance of the solder. Examining the mechanical behavior and reliability of Pb-free solders is difficult, primarily because a methodology to characterize the microstructure and the mechanics of deformation at these extremely small length scales has yet to be developed.

In this study, Sn grain orientation and Cu6Sn5 IMC fraction, size, and morphology are characterized in 3D, in pure Sn based solder joints. The obtained results show differences in morphology of Sn grains and IMC precipitates as a function of location within the solder joint indicating influence of local cooling rate differences. Ex situ and in situ electromigration tests done on 250 um and 500 um pure Sn solder joints elucidate the evolution of microstructure, specifically Sn grain growth, IMC segregation and surface degradation. This research implements 3D quantification of microstructural features over micro and nano-scales, thereby enabling a multi-scale / multi-characterization approach.
ContributorsKirubanandham, Antony (Author) / Chawla, Nikhilesh (Thesis advisor) / Jiao, Yang (Committee member) / Lu, Minhua (Committee member) / Rajagopalan, Jagannathan (Committee member) / Arizona State University (Publisher)
Created2016
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Description
An accurate knowledge of the complex microstructure of a heterogeneous material is crucial for quantitative structure-property relations establishment and its performance prediction and optimization. X-ray tomography has provided a non-destructive means for microstructure characterization in both 3D and 4D (i.e., structural evolution over time). Traditional reconstruction algorithms like filtered-back-projection (FBP)

An accurate knowledge of the complex microstructure of a heterogeneous material is crucial for quantitative structure-property relations establishment and its performance prediction and optimization. X-ray tomography has provided a non-destructive means for microstructure characterization in both 3D and 4D (i.e., structural evolution over time). Traditional reconstruction algorithms like filtered-back-projection (FBP) method or algebraic reconstruction techniques (ART) require huge number of tomographic projections and segmentation process before conducting microstructural quantification. This can be quite time consuming and computationally intensive.

In this thesis, a novel procedure is first presented that allows one to directly extract key structural information in forms of spatial correlation functions from limited x-ray tomography data. The key component of the procedure is the computation of a “probability map”, which provides the probability of an arbitrary point in the material system belonging to specific phase. The correlation functions of interest are then readily computed from the probability map. Using effective medium theory, accurate predictions of physical properties (e.g., elastic moduli) can be obtained.

Secondly, a stochastic optimization procedure that enables one to accurately reconstruct material microstructure from a small number of x-ray tomographic projections (e.g., 20 - 40) is presented. Moreover, a stochastic procedure for multi-modal data fusion is proposed, where both X-ray projections and correlation functions computed from limited 2D optical images are fused to accurately reconstruct complex heterogeneous materials in 3D. This multi-modal reconstruction algorithm is proved to be able to integrate the complementary data to perform an excellent optimization procedure, which indicates its high efficiency in using limited structural information.

Finally, the accuracy of the stochastic reconstruction procedure using limited X-ray projection data is ascertained by analyzing the microstructural degeneracy and the roughness of energy landscape associated with different number of projections. Ground-state degeneracy of a microstructure is found to decrease with increasing number of projections, which indicates a higher probability that the reconstructed configurations match the actual microstructure. The roughness of energy landscape can also provide information about the complexity and convergence behavior of the reconstruction for given microstructures and projection number.
ContributorsLi, Hechao (Author) / Jiao, Yang (Thesis advisor) / Chawla, Nikhilesh (Committee member) / Liu, Yongming (Committee member) / Ren, Yi (Committee member) / Mu, Bin (Committee member) / Arizona State University (Publisher)
Created2017
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Description
Dealloying, the selective electrochemical dissolution of an active component from an alloy, often results in nanoscale bi-continuous solid/void morphologies. These structures are attracting attention for a wide range of applications including catalysis, sensing and actuation. The evolution of these nanoporous structures has been widely studied for the case at low

Dealloying, the selective electrochemical dissolution of an active component from an alloy, often results in nanoscale bi-continuous solid/void morphologies. These structures are attracting attention for a wide range of applications including catalysis, sensing and actuation. The evolution of these nanoporous structures has been widely studied for the case at low homologous temperature, TH, such as in Ag-Au, Cu-Au, Cu-Pt, etc. Since at low TH the solid-state mobility of the components is of order 10-30 cm2s-1 or less, percolation dissolution is the only mechanism available to support dealloying over technologically relevant time scales. Without the necessity of solid-state mass transport, percolation dissolution involves sharp transitions based on two key features, the parting limit and critical potential.

Dealloying under conditions of high TH, (or high intrinsic diffusivity of the more electrochemically reactive component) is considerably more complicated than at low TH. Since solid-state mass transport is available to support this process, a rich set of morphologies, including negative or void dendrites, Kirkendall voids and bi-continuous porous structures, can evolve. In order to study dealloying at high TH we have examined the behavior of Li-Sn and Li-Pb alloys. The intrinsic diffusivities of Li were measured in these alloys using electrochemical titration and time of flight measurements. Morphology evolution was studied with varying alloy composition, host dimension and imposed electrochemical conditions. Owing to diffusive transport, there is no parting limit for dealloying, however, there is a compositional threshold (pPD) as well as a critical potential for the operation of percolation dissolution and the formation of bi-continuous structures. Negative or void dendrite morphologies evolve at compositions below pPD and at large values of the applied electrochemical potential when the rate of dealloying is limited by solid-state mass transport. This process is isomorphic to dendrite formation in electrodeposition. Kirkendall voiding morphologies evolve below the critical potential over the entire range of alloy compositions.

We summarize our results by introducing dealloying morphology diagrams that we use to graphically illustrate the electrochemical conditions resulting in various morphologies that can form under conditions of low and high TH.
ContributorsGeng, Ke (Author) / Sieradzki, Karl (Thesis advisor) / Crozier, Peter (Committee member) / Chan, Candace (Committee member) / Jiao, Yang (Committee member) / Arizona State University (Publisher)
Created2017
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Description在我国绩效管理领域,国内企业目前大多仅适用客观评价指标,而往往忽略了更有弹性的主管评价等主观评价指标。但在世界范围内,随着绩效管理理论的不断发展,以平衡计分卡(BSC)为代表的新型绩效管理体系管理范围更加广泛,除了客观业绩之外,还将很多主观指标也纳入绩效评价系统内,并且得到了诸多跨国公司的引用。为了探究以主管评价为代表的主观指标与客观业绩之间的关系,本文以R公司为例,基于其内部的实际数据,分析了员工业绩与主管评价之间的相互关系。研究发现,员工历史客观业绩与主管评价呈正相关关系,且相较于员工长期客观业绩,这种关系在员工短期业绩中更加明显。基于此,研究还发现,主管历史评价与员工后期的客观业绩也呈正相关关系,且相较于前期主管评价,这种关系在当期主管评价中更加明显。除此之外,本文还发现主管和员工的性别差别和学历差别会同时减弱上述员工业绩与主管评价之间的正相关关系。综上,本文研究结果为企业设计和制定绩效考核标准提供了一定的参考,有助于企业更好地进行绩效体系的构建。
ContributorsJin, Tao (Author) / Shen, Wei (Thesis advisor) / Chang, Chun (Thesis advisor) / Wu, Fei (Committee member) / Arizona State University (Publisher)
Created2022
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Description自雇司机是公路货运司机中比例人数最多、最基层的一员,他们在公路物流行业中扮演着极为重要的角色,他们承担着各种来源的压力。本文以疫情前后按揭购买卡车的自雇司机为研究样本,基于本研究收集到的独特数据,研究发现自雇卡车司机在面临按揭压力时,倾向采取更为激进的经营及驾驶行为,表现为更少的休息天数、更长的工作时长以及更危险的高速驾驶行为,并在一系列稳健性检验中基本结论仍然存在;基于新冠疫情事件研究发现,新冠疫情带来的非预期性经济停摆和收入中断,导致疫情前的发生的按揭贷款的卡车司机面临更强的还款压力,在经济恢复后面对按揭压力更有可能采用激进的经营和驾驶行为;进一步,通过机制检验研究本文发现这种按揭压力主要表现为担心当前或者未来发生不能及时偿还按揭款。再者,基于人格性征和家庭支持的调节效应检验,本文发现神经质人格特征、谨慎尽责性人格特征以及工作压力感没有在按揭压力与自雇卡车司机激进的经营和驾驶选择上起到调节作用,这可能是自雇卡车司机面临的按揭压力都很大,个体性格特征很大程度无法缓和其压力感,而家庭的支持和家庭-工作平衡可以有效缓解自雇卡车司机面临按揭压力时提高工作时长和危险驾驶行为的倾向。 最后,本文设计一项随机对照干预实验,向自雇卡车司机发送短息或者微信,提醒他们避免疲劳驾驶和危险超速驾驶,然后观察发送短信微信前后自雇卡车司机经营及驾驶行为的变化,识别考察外界积极主动的关心和提醒能否起到相应的后果。本文发现对自雇卡车司机获得外部主动积极地的关心和提醒,在面临按揭压力时意识到简单地减少休息增加运营时长以及采用危险驾驶行为抢时间的策略可能给其带来很大的风险,从而相应地缓解对按揭压力的过度反应;进一步调节作用检验表明,短信干预实验在神经质和谨慎尽责性人格司机中起到更大的减缓作用,同时家庭支持较少时短信干预实现效应也更为明显。
ContributorsMa, Liqun (Author) / Shen, Wei (Thesis advisor) / Wu, Fei (Thesis advisor) / Zhang, Zhen (Committee member) / Arizona State University (Publisher)
Created2021
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Description本文对中国制药企业并购溢价影响因素进行了研究,提出了对制药企业并购非常重要的两个新的影响因素:可生产药品批文和在研新药批文。本文以2011年1月—2019年12月间我国制药行业上市公司并购事件为样本,对在研新药和可生产药品批文的价值从四个维度度量:是否有在研新药和可生产药品批文;在研新药数量及可生产药品批文数量;根据创新药和仿制药两个类别进行细分;标的企业所拥有的在研新药和可生产药品批文的市场价值。论文发现药品批文对企业并购溢价的影响不是很显著。进一步的,本文探究了药品批文对主并企业的对被并购公司的估值的影响。实证结果表明,我国制药企业在并购估值时确实会考虑到在研新药和可生产药品批文的价值。本文还发现对于可生产药品来说,相对创新药,被并购公司持有的仿制药批文影响更显著。而对于在研新药来说,主并企业更看重在研的创新药,在研仿制药对并购估值的影响不大。最后,本文选取了两个代表性案例进一步分析和探讨药品批文对企业并购的影响。
ContributorsYe, Tao (Author) / Shen, Wei (Thesis advisor) / Chang, Chun (Thesis advisor) / Jiang, Zhan (Committee member) / Gu, Bin (Committee member) / Arizona State University (Publisher)
Created2022