The cost of failure: An empirical look at the financial effect of business failure on the self-employed

Harting, Troy R University of Virginia 2005 해외박사(DDOD)

Despite a long history of research into failure rates and the causes of small business failure, we know very little about the financial consequences of losing a business. In this dissertation I take a longitudinal sample of failed self-employed business owners from the Panel Study of Income Dynamics and compare their wealth accumulation to that of demographically comparable families who have not experienced entrepreneurial failure. Surprisingly, business failure is associated with slightly higher wealth at closure, with the resulting "failure bonus" dissipating in five years or less. I also conduct exploratory analysis to further characterize the wealth accumulation of failed households and analyze their propensity for subsequent self-employment. The higher wealth observed immediately after failure indicates that the typical household involved in self-employment may still retain a significant amount of the precautionary savings that were accumulated in preparation for an attempt at entrepreneurship. It suggests that although some households undoubtedly do lose money when a business fails, most escape relatively unscathed by exiting quickly rather than persisting in the face of an unfavorable business environment. This behavior has implications for how we interpret liquidity constraints to entrepreneurship, as well as for government policy in support of small businesses.

Student learning outcomes in a computer applications module: Online vs. face-to-face instruction

Harting, Kathleen A Southern Illinois University at Carbondale 2005 해외박사(DDOD)

The purpose of the study was to contribute to a better understanding of student learning outcomes in a web-based instructional environment. In addition, the study sought to determine if there was a significant difference between the characteristics of students who chose the entirely online web-based instruction to complete a spreadsheet software application module and those who chose the traditional lecture/demonstration instruction. The problem of the study was to determine if student achievement in a university computer applications course module is influenced by the instructional delivery method selected by the student and to discover if there is a relationship between instructional delivery method and student demographics. A quasi-experimental research design was used to conduct the study using students enrolled in six intact sections of a beginning computer applications course at a Midwestern state university. The study took place during the Microsoft Excel module of the course. There were 95 students who chose to complete this module using strictly online web-based instruction, while 106 students chose a traditional lecture/demonstration classroom setting. Both groups had the same instructional materials, and completed the same assessments. At the conclusion of the module, both groups took two assessments in the classroom: a web-based Excel concepts exam using WebCT and a hands-on Excel application exam. The instrument used to measure student achievement was a spreadsheet concept exam and a spreadsheet application exam. The majority of subjects who participated in this study were female; freshmen; in the 18--19 age group; enrolled for 15 semester hours at the time the study occurred; and had a cumulative GPA between 2.01 and 3.0 using a 4.0 system. Using an independent samples t-test, no statistically significant difference was found between exam scores and instructional delivery method. The only statistically significant difference found related to instructional delivery was the variance of a student's ACT score, which did show a positive correlation based on student's choice of the instructional delivery method. Recommendations included further investigation using an entire course to determine if instructional delivery impacts student achievement within the individual modules and the entire course.

Pyrolysis and combustion of HTPB, GAP, and OXSOL for hybrid rocket motor applications

Harting, George C The Pennsylvania State University 2000 해외박사(DDOD)

HTPB was studied under conditions that closely simulate a hybrid rocket motor. The results of the HTPB characterization indicated that the activation energy for pyrolysis was relatively low for surface temperatures between 700 to 1000 K. For the conductive heat technique, the pyrolysis activation energy was 4.9 kcal/mole. The pyrolysis activation energy in an oxidizing environment was 2.6–2.9 kcal/mole and was found to depend on pressure. The characterization of GAP energetic fuel was studied using several techniques: a strand burner, small motor firings, and a hybrid slab motor. The burning rate of GAP was found to have a moderate pressure exponent of 0.56 for pressures up to 13.5 MPa. A slope break in the burn rate curve was found to occur at pressures above 13.5 MPa with a pressure exponent of 0.12. Additionally, the temperature sensitivity of GAP had a pressure dependence below 10 MPa and ranged from 0.015 to 0.008 K<super>−1</super>. Above 10 MPa, the temperature sensitivity was constant at 0.008 K<super>−1</super>. Analysis of the decomposition mechanism of GAP indicated an activation energy for regression rate of 41 kcal/mol at surface temperatures up to 712 K and an activation energy of 6.6 kcal/mol at higher surface temperatures. The gas-phase heat flux was determined to be approximately 20 W/cm<super>2</super>, which is two orders of magnitude lower than the surface heat release rate of 1600 W/cm<super> 2</super>. The pressure dependence of GAP burning rate can be explained as a surface heat release process which is controlled by desorption of energetic GAP fragments. Based upon the small motor firings of GAP and the low gas-phase temperature and heat flux, the gas-phase composition appears to not change much from the initial decomposition products at the surface. Liquid strand burning measurements indicated a dependence of OXSOL regression rate on tube diameter. A diameter sensitivity term, analogous to the temperature sensitivity of solid propellants, was introduced and was found to decrease with pressure from 0.07 to 0.04 mm<super>−1</super>. Analysis of the gas phase temperatures indicated that water vaporization played a key role in the regression rate of OXSOL at pressures below 9 MPa.

AN EXPERIMENTAL INVESTIGATION OF THE EVOLUTION OF TURBULENT POTENTIAL AND KINETIC ENERGIES AND THE VERTICAL TEMPERATURE STRUCTURE OF HOMOGENEOUS STABLY STRATIFIED SHEARED TURBULENCE (STRATIFIED FLOW)

KELLER, KURT HARTING UNIVERSITY OF CALIFORNIA, SAN DIEGO 1999 해외박사(DDOD)

Homogeneous stably stratified sheared turbulence has been studied in detail using both standard fixed point methods and a new rapid vertical profiling system. A 10-layer thermally stratified wind tunnel generated mean flows in which both the mean temperature gradient and the mean velocity gradient could be adjusted independently. Six cases of mean flows, characterized by the gradient Richardson number, <math> <f> Ri<inf>g</inf>=N²/<fen lp="par"><rm>d<it>U/<rm>d<it> z</it></rm></it></rm><rp post="par"></fen>²,</f> </math> were studied, with initial values of <math> <f> Ri<inf>g</inf></f> </math> = 0.015, 0.055, 0.095, 0.135, 0.25 and 0.5. The turbulence was initiated with a 2.54 cm bi-planar grid. Fixed point measurements of streamwise and vertical velocity fluctuations and temperature were made at several streamwise stations using standard X-wire and cold-wire techniques. Vertical profiles of temperature were made at several streamwise stations using standard cold-wire techniques and a rapid vertical traverse. Multipoint measurements of the temperature field were also made using a vertically aligned 8-point cold-wire rake. The turbulent kinetic and potential energies were found to have identical, exponential growth rates with respect to the nondimensional time scale, τ = <italic>St</italic>. Evaluation of the first-order terms in the evolution equations for turbulent kinetic and potential energies show that the Osborn-Cox model [Osborn & Cox (1972)] is generally not valid for these types of flows. A self-preserving solution was derived and shown to predict the exponential growth, and the constant ratio of kinetic and potential energies, for homogeneous stratified shear turbulence. The vertical structure of the temperature field at low <math> <f> Ri<inf>g</inf></f> </math> was found to be dominated by high stable gradient regions adjacent to unstable patches. These structures are associated with large scale advective flux of buoyancy. Comparison of vertical and horizontal wavenumber spectra of temperature show that spectral energy in the vertical direction is confined to a narrower band of wavenumbers. This difference leads to a small scale anisotropy, which is controlled by both shear and stratification. Measurements of Thorpe scales and available potential energy show that the energy associated with overturn patches is much less than the total potential energy and that decay of the turbulence reduces the number of overturn patches but not the scale of the patches.

'리델 하트'(B. H. Liddell Hart)의 間接接近 戰略思想

김길영 國防大學院 1990 국내석사

Prosodic Repulsion in English

William Hart Hankuk University of Foreign Studies. Graduate Sch 2017 국내박사

영어의 운율적 반발 본 연구는 영어를 비롯해 여러 언어에서 나타나는 다양한 음운 구조 및 현상들을 Hart (2015a)에서 처음으로 언급된 운율적 반발(prosodic repulsion)이라는 개념을 이용하여 설명하고자 한다. Hart (2015a)에서는 운율적 반발을 “모든 언어에 나타나는 다양한 음운 구조 및 현상들에 영향을 미치는 반발력”이라고 정의한다. 본 연구는 이러한 개념을 좀 더 구체적인 사례에 적용시켜, 분절음과 같은 가장 기본적인 단위에서부터 운율단어와 같은 가장 복잡한 단위에 이르기까지 모든 운율 구조가 서로 상충하는 요소들 사이에 발생하는 힘의 균형을 통해 결정되고 설명될 수 있다고 주장한다. 다시 말해, 음운적 요소들은 그들 사이에 발생하는 인력과 반발력이라는 상충하는 힘들로 인해 서로를 잡아당김과 동시에 밀어내기도 한다. 본 연구는 요소들 사이의 힘의 관계를 정립하는 과정에서 음운 구조가 결정된다고 주장한다. 앞서 언급된 두 가지 힘 중 인력과 관련하여서는 정렬(alignment; Selkirk 1984, McCarthy and Prince 1993b)이라는 이론적 장치가 활발히 사용된 반면, 밀어 내는 힘에 관해서는 아직 제대로 논의된 바가 없다. 이러한 점에서 본 연구는 반발력이 하는 주요한 역할을 영어를 비롯한 여러 언어 사례들을 통해 입증해 보이고자 한다는 점에서 그 의의를 가진다. 나아가 이러한 발견은 음운 구조의 본질에 대해 고찰해 볼 수 있는 기회를 제공할 수 있다는 점에서 주목할 만하다. 본 연구는 음운 현상에서 반발력이 하는 역할을 제약을 기반으로 한 최적성 이론 (Optimality Theory; Prince and Smolensky 1993/2004)을 사용하여 설명하고자 하며, 이를 위해 필요한 제약으로는 아래에 제시된 대로, 음운적 반발력을 총망라하는 일반화된 반발(Generalized Repulsion)제약이 있다. (i) Generalized Repulsion: REPEL(Category 1, Category 2, Edge, Buffer) 위 제약에 따르면, Category 1에 해당하는 요소와 Category 2에 해당하는 요소의 왼쪽이나 오른쪽 끝 사이에는 반발력이 존재하여 두 요소가 서로 인접할 수 없다. 또한 여기에는 반발력을 완화시켜주는 완충 요소(Buffer)가 작용하여, 두 요소 사이의 최소 거리를 결정해준다. 이러한 제약의 골자를 기반으로 영어의 음운 구조를 분석하기 위해, 아래와 같은 일반적 반발에 속하는 세부 제약들이 사용되었다. (ii) Consonant extrametricality: REPEL(μ, PrWd, R, C) (ii)에 제시된 제약에 따르면 운율어의 모라는 운율 단어(prosodic word)의 오른쪽 끝에 정렬될 수 없다. 왜냐하면 해당 제약에 사용된 완충 요소에 따라 모라와 운율 단어 오른쪽 끝 사이의 거리는 최소한 자음 하나가 되어야 하기 때문이다. 이 제약을 활용할 수 있는 대표적인 현상으로는 영어에서 나타나는 어말 비(非)-모라 현상 (nonmoraicity)을 들 수 있다. 예를 들면, 이 제약을 활용할 경우 왜 영어의 devélop과 같이 어말에 CVC 구조를 가지는 단어가 eráse (어말 CVVC 구조) 또는 tormént (어말 CVCC구조)와 같은 단어들과 다른 강세 유형을 보이는지를 설명할 수 있다. (iii) Syllable extrametricality: REPEL(FtHd, PrWd, R, σ) 다음에 제시된 음절 운율외성(syllable extrametricality) 제약은 핵음보(head foot)가 운율 단어의 오른쪽 끝과 정렬되지 못하게 한다. 이 때, 완충 요소에 따르면 두 요소 사이의 최소한의 거리는 1음절이다. 이 제약은 품사에 따라 다르게 나타나는 영어의 강세 규칙을 설명하는데 유용하게 사용될 수 있다. 좀 더 구체적으로 설명하자면, 영어의 de(vélop), e(ráse), tor(mént)와 같은 동사의 경우, 마지막 음절이 항상 음보에 속하는데 반해 A(méri)ca, (géne)sis, (láby)rinth와 같은 명사의 마지막 음절은 운율외성으로 처리된다. 이를 (iii)의 제약으로 설명해보자면, 명사는 동사와 달리 완충 요소로 인해 핵음보가 운율 단어의 오른쪽 끝으로부터 최소한 1음절의 간격을 두고 위치해야 하기 때문에 이와 같은 강세 유형을 보이는 것이다. (iv) Primary stress retraction: REPEL(FtHd, PrWd, R, Ft) 마지막으로 제시된 제약은 영어에 일반적으로 나타나는 강세 유형과 다른 예외의 경우를 설명하는데 유용하다. 일반적으로 영어에서는 제 1강세가 단어의 가장 오른쪽 음보에 위치하는 경향이 있지만 여기에는 예외가 존재한다. 이러한 예외는 (Àdi)(rón)-(dàck)이나 (cáta)ma(ràn)와 같은 단일형태소 단어 뿐만 아니라, 하나 이상의 형태소로 이루어진 (désig)(nàte), (jéopar)(dìze)와 같은 단어들에서도 살펴볼 수 있다. 이러한 단어들의 공통점은 제 1강세가 단어의 가장 오른쪽 음보가 아닌 끝에서 두번째 음보에 주어진다는 점이다. 이러한 현상은 (iii)에서 제시된 제약과 같이 핵음보와 운율 단어의 오른쪽 끝 사이에 저항력을 적용한 (iv)의 제약으로 설명할 수 있다. 다만, 두 제약의 차이는 후자의 경우 음절이 아닌 전체 음보가 완충요소로 작용한다는 점이다. 이 제약을 특정한 접사 및 단어에 적용할 경우 제 1강세가 끝에서 두번째 음보로 “뒤로 후퇴”하는 현상을 설명할 수 있다. Prosodic Repulsion in English This dissertation explores and expands upon the concept of prosodic repulsion, first introduced in Hart (2015a) to describe a force of resistance that can seen to be exerting an influence on various kinds of phonological structures and phenomena across all human languages. It is argued that all prosodic structures, from the most basic units to the most complex ones, are defined by a balance of opposing forces that simultaneous draw phonological constituents together while pushing them away from each other at the same time, representing an eternal structural struggle between the forces of attraction and repulsion. While the former of these two forces has been investigated in much previous research with the theoretical device of alignment (cf. Selkirk 1984; McCarthy and Prince 1993b), the latter has never been recognized or received a unified treatment, and is thus the sole focus of this project. In presenting a detailed case study of the prosodic structure and phonological phenomena of the English language, as well as evidence from various other languages of the world, this dissertation will demonstrate the major role played by the force of repulsion in defining the phonological structures of human languages. As the analyses put forward in this work are presented within the constraintbased framework of Optimality Theory (Prince and Smolensky 1993/2004), the following constraint scheme for Generalized Repulsion is proposed to encapsulate the force of prosodic repulsion: (i) Generalized Repulsion: REPEL(Category 1, Category 2, Edge, Buffer) What this scheme entails is that a prosodic constituent of Category 1 resists alignment with a constituent of Category 2 at either the left or the right Edge, and requires the unit specified as the Buffer as the minimal distance between the two, this buffer being needed to quell the force of repulsion and hold the two specified constituents apart from each other. A few of the Generalized Repulsion constraints used in the analyses of English prosodic structures are presented below. (ii) Consonant extrametricality: REPEL(μ, PrWd, R, C) The constraint in (ii) prohibits the alignment of a mora with the right edge of a prosodic word, demanding at the minimum a consonantal segment serving as a buffer to quell the resistance between these two constituents and keep them apart. This constraint can be used to account for the nonmoraicity of word-final consonants in languages such as English, which results in differing patterns of stress for CVC-final words such as iv devélop in comparison to CVVC-final words such as eráse and CVCC-final words such as tormént. (iii) Syllable extrametricality: REPEL(FtHd, PrWd, R, σ) The repulsion constraint in (iii) bans any head foot from alignment with the right edge of the word in which it is situated, minimally requiring a syllabic buffer to hold the two apart from each other. This constraint allows us to illuminate the long-noted difference in stress patterns between lexical items of different word categories in English. While the final syllables of verbs such as de(vélop), e(ráse) and tor(mént) are always parsed into feet, the final syllables of nouns such as A(méri)ca, (géne)sis and (láby)rinth are not. It is the category-specific constraint in (iii) which accounts for this difference, demanding that the head foot of a noun be pushed back from the right edge of the word by the distance of at least a syllable. (iv) Primary stress retraction: REPEL(FtHd, PrWd, R, Ft) While the usual tendency in English is for primary stress to fall on the rightmost foot of a word, this is not always the case. In monomorphemic words such as (Àdi)(rón)(dàck) and (cáta)ma(ràn), as well as in morphologically complex words like (désig)(nàte) and (jéopar)(dìze), the primary stress is located not on the rightmost foot, but rather on the penultimate one. This state of affairs can be accounted for using the constraint in (iv), which encodes a force of resistance acting upon the head foot of a word, just like the constraint in (iii). What sets the constraint in (iv) apart from its predecessor is the buffer, which is an entire foot rather than a mere syllable. Due to the influence of this constraint, which is proposed to apply specifically to particular affixes and lexical groups, primary stress appears to be “retracted backward” to the penultimate foot. In addition to these aspects of prosodic structure, repulsion constraints are proposed to account for several other areas of English phonology, including syllable structure, foot structure, the stress well environment, final tensing, closed syllable shortening, prevocalic tensing, glottal epenthesis, name truncation and rhythm reversal. While the examination of English prosodic structure and phenomena represents the key offering of this dissertation, this case study of a single language is followed by an exploration of the many ways in which the concept of repulsion can be applied to other languages of the world in order to illuminate various phenomena in other areas of phonological research, including tonal phonology, accentual systems, intonation contours, and constraints on morphemic structure.

Synthetic studies on tetramic acid macrolactams

Hart, Amy C University of Colorado at Boulder 2005 해외박사(DDOD)

Cylindramide A is a tetramic acid macrolactam isolated by Fusetani and coworkers in 1993 from the marine sponge Halichondria cylindrata. Although isolated from a sponge, similar structures have recently been obtained from terrestrial bacteria, which strongly suggests a microbial origin for cylindramide A. Additionally, cylindramide A has demonstrated cytotoxic activity against B16 melanoma cell lines (IC50 = 0.8mug/mL), although inadequate quantities of material were isolated to allow broader testing. Our interest in cylindramide A was furthered by its unique architecture which contains elements from both polyketide and non-ribosomal peptide biosynthesis. Cylindramide A is comprised of two major subunits: a dienyl macrolactam that also encapsulates a tetramic acid, and a stereochemically rich bicyclo[3.3.0]octene. Our overall synthesis strategy was based on the use of tandem olefin metathesis. While olefin metathesis has been utilized by synthetic chemists as a way to functionalize olefins and close macrocycles, tandem metathesis reactions have seen little use in total synthesis. We have developed a tandem ring-opening-ring-closing-cross metathesis that allows rapid access to the highly functionalized bicyclo[3.3.0]octene core of cylindramide A. The tandem metathesis chemistry developed for cylindramide A has also been applied to other molecules in this class, including geodin A. The bicyclo[3.3.0]octene arising from the tandem metathesis sequence could be elaborated to a number of substrates suitable for coupling with the amino acid portion of the molecule. Use of a Stille reaction, a Sonogashira reaction, and a Homer-Wadsworth-Emmons reaction to couple the two halves of the molecule was investigated. Ultimately, the Horner-Wadsworth-Emmons approach was most successful. The total synthesis was accomplished by macrocyclic closure via intramolecular nucleophilic trapping of an acyl ketene intermediate which was formed in situ by thermolysis of a dioxenone. Several deprotections and installation of the tetramic acid by Lacey-Dieckmann cyclization provided cylindramide A in 19 steps (longest linear sequence).

Aci Tatli Yiyoruz: Bitter or sweet we eat. The economics of love and marriage in Orselli village (Turkey)

Hart, Kimberly Indiana University 2005 해외박사(DDOD)

Aci Tatli Yiyoruz explores transformations in gender, kin relationships and marriage in a Turkish village over a forty year period and argues that there is a connection between economic and social change, which is mediated by a local-level politicization of ideas of tradition and modernity. Rather than relying on abstract, unembodied notions of modernity, I provide a close and concrete analysis of the material, emotional and personal interpretations of rural modernity based on twenty months of intensive field study, from 1989 to 2004, using ethnographic methods, including survey, interviews, photography, video and participant-observation. I argue that the villagers are engaged in a deliberate process of creating links to a national and a global Muslim identity through the adoption of infrastructure, secular education, orthodox Sunni Islam, and technology. Furthermore, they have attempted to make their village society sustainable in a women's carpet weaving cooperative. In the cooperative, ideas of modernity and tradition come together as women take on new roles as weavers of "traditional," new-production carpets in an export-only business. Women, therefore, embody an important pivotal position between constructions of gender in a conservative Muslim community, skilled craftswomen in a local cottage industry dedicated to "traditional" weavings, and actors in a transforming economy based on herding. In the context of these realities, I focus the second half of my study on the struggles of young women in making a transition to adulthood through marriage and argue that their experiences demonstrate an imaginative engagement with modernity on an intimate and individual level. While adult women, that is married women, have a position of increased power and agency as weavers, their daughters must embody "traditional" ideals of gender in displaying their obedience and steady labor as unpaid weavers and domestic workers in their natal households. Despite the interest in progressive, modernist ideals, the community maintains conservative notions of gender, which are institutionalized in Islamic practice, formalized by kinship, expressed economically through weaving and other forms of labor, and enacted in the rites of marriage. I explore daughters' agency in marriage practices, including elopement and abduction, arranged marriage and innovations in romantic attachments. Material transformations connect a transforming economic and social world to marriage through dowry/trousseaux, the role of traditional textiles and the commercialization of carpet weaving.

Neural Representation of Economic Parameters by Dopamine Release: A Quantitative Analysis

Hart, Andrew S University of Washington 2012 해외박사(DDOD)

The goal of the field of neuroeconomics is to understand the neural representations of variables relevant to theories of decision-making. These variables include the expected value of a prospect and the uncertainty associated with a choice. Recordings from dopamine neurons in awake, behaving monkeys strongly indicate that dopamine plays a role in representing these parameters. A complementary role of dopamine is the encoding of a reward prediction error signal, which can be used to iteratively update the expected value associated with a cue that predicts reward. While these roles of dopamine neurons have been qualitatively described, there are very few quantitative analyses that relate dopamine to these variables, and none have been conducted at the level of dopamine release. In the current thesis, I combined simple Pavlovian and operant behavioral tasks with recordings of dopamine release in the nucleus accumbens core of rats, using the electrochemical method fast-scan cyclic voltammetry. To address the relationship between dopamine release and expected value and uncertainty, I applied regression analyses to conditioned stimulus-evoked dopamine signals during learning. To address the relationship between dopamine release and reward prediction error signaling, I applied an axiomatic reward prediction error model to reward-evoked dopamine release from rats performing an operant task with probabilistic rewards. I report that dopamine release correlates with expected value, uncertainty, and reward prediction error signals. Expected value and uncertainty signals may be blended at the level of dopamine release, and reward prediction error signals can be represented in a balanced or an imbalanced manner depending on the range of errors studied and the behavioral task.

An history analysis of three New York production of Eugene O'Neill's "long day's journer into night"

Hart, Doris U. M. I. 1982 국내박사