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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
311

Hypothetical, not Fictional Worlds

Weinert, Friedel January 2016 (has links)
yes / This paper critically analyzes the fiction-view of scientific modeling, which exploits presumed analogies between literary fiction and model building in science. The basic idea is that in both fiction and scientific modeling fictional worlds are created. The paper argues that the fiction-view comes closest to certain scientific thought experiments, especially those involving demons in science and to literary movements like naturalism. But the paper concludes that the dissimilarities prevail over the similarities. The fiction-view fails to do justice to the plurality of model types used in science; it fails to realize that a function like idealization only makes sense in science because models, unlike works of fiction, can be de-idealized; it fails to distinguish sufficiently between the make-believe (fictional) worlds created in fiction and the hypothetical (as-if) worlds envisaged in models. Representation characterized in the fiction-view as a license to draw inferences does not sufficiently distinguish between inferences in fiction from inferences in scientific modeling. To highlight the contrast the paper proposes to explicate representation in terms of satisfaction of constraints
312

Three Essays on Product Market Capital Market Interactions

Chowdhury, Jaideep 10 December 2008 (has links)
The Industrial Organization literature investigates the product market decisions of a firm while the corporate finance literature explores the financing decisions of the firm. But the truth is both the financing decisions and the product market decisions are interdependent and should be modeled together to develop a better understanding of a firm's decisions. This thesis takes a step in that direction. The manager of a firm caters to the equity holders of the firm who are protected by limited liability. Ex-ante debt is issued and at the time of product market decision, debt is exogenous. The traditional product market capital market interaction literature has argued that debt financing leads to more aggressive product market strategies. If debt is treated as endogenous and/or the switching state of nature is endogenous, it can be shown that debt financing may lead to less aggressive product market strategies. Further, if external financing consists of both debt and equity financing, it is shown that a financially constrained firm shall produce less than what it would have produced if it was not financially constrained. Finally, managerial compensation is reported to be one of the reasons for product market aggressiveness of a firm in the context of product market capital market interaction. / Ph. D.
313

On a Class of Parametrized Domain Optimization Problems with Mixed Boundary Condition Types

Letona Bolivar, Cristina Felicitas 19 October 2016 (has links)
The methods for solving domain optimization problems depends on the case of study. There are methods that have been developed for the discretized problem, but not much is done in the infinite dimensional case. We analyze the theoretical aspects of the infinite dimensional case for a particular domain optimization problem where a portion of the boundary is parametrized, these results involve the existence of the solution to our problem and the calculation of the derivative of the shape functional. Shape optimization problems have a long history of mathematical study and a wide range of applications. In recent decades there has been an interest in solving these problems with partial differential equation (PDE) constraints. We consider a special class of PDE-constrained shape optimization problems where different boundary condition types (Dirichlet and Neumann) are imposed on the same boundary segment. We also consider the case where the interface between these different boundary condition types may also be parameter dependent. This study also includes special cases where the shape of the region where the PDE is imposed does not change, but the domain of the partial differential operator is parameter dependent, due to the change in boundary condition type. Our treatment centers on the infinite dimensional formulation of the optimization problem. We consider existence of solutions as well as the calculation of derivatives of the associated shape functionals via adjoint solutions. These derivative formulations serve as a starting point for practical numerical approximations. / Ph. D.
314

Contextual Shaping of Student Design Practices: The Role of Constraint in First-Year Engineering Design

Goncher, Andrea 07 December 2012 (has links)
Research on engineering design is a core area of concern within engineering education, and a fundamental understanding of how engineering students approach and undertake design is necessary in order to develop effective design models and pedagogies. This dissertation contributes to scholarship on engineering design by addressing a critical, but as yet underexplored, problem: how does the context in which students design shape their design practices? Using a qualitative study comprising of video data of design sessions, focus group interviews with students, and archives of their design work, this research explored how design decisions and actions are shaped by context, specifically the context of higher education. To develop a theoretical explanation for observed behavior, this study used the "nested structuration" framework proposed by Perlow, Gittell, & Katz (2004). This framework explicated how teamwork is shaped by mutually reinforcing relationships at the individual, organizational, and institutional levels. I appropriated this framework to look specifically at how engineering students working on a course-related design project identify constraints that guide their design and how these constraints emerge as students interact while working on the project. I first identified and characterized the parameters associated with the design project from the student perspective and then, through multi-case studies of four design teams, I looked at the role these parameters play in student design practices. This qualitative investigation of first-year engineering student design teams revealed mutual and interconnected relationships between students and the organizations and institutions that they are a part of. In addition to contributing to research on engineering design, this work provides guidelines and practices to help design educators develop more effective design projects by incorporating constraints that enable effective design and learning. Moreover, I found that when appropriated in the context of higher education, multiple sublevels existed within nested structuration's organizational context and included course-level and project-level factors. The implications of this research can be used to improve the design of engineering course projects as well as the design of research efforts related to design in engineering education. / Ph. D.
315

Pinpointing production constraints faced by female-headed households in rural Malawi

Russ, Katheryn Niles 02 October 2008 (has links)
In this study, an econometric model for testing whether female-headed households face unique constraints to maize production in Malawi is presented. A simulation is performed on the first-order equations of smallholder maize production functions and predicted marginal products are tested against observed input-output price ratios to detect input constraints and allocative inefficiency. Technical efficiency is also compared among headship gender categories. Results indicate that de jure female-headed households are less technically efficient than de facto female- and male-headed households. However, no evidence is found indicating that gender-specific input constraints exist. This study finds surplus labor present throughout Malawi’s smallholder sector and discusses policy alternatives in the context of poverty alleviation. / Master of Science
316

Constraints, a model of computation

Mantha, Suryanarayana M. 17 November 2012 (has links)
In this thesis constraint solving/satisfaction is presented as a model of computation. Advantages of using constraints as a paradigm of programming are presented. A semantic schema for constraint based computations is given, following a brief survey of the more important systems based on constraints. These systems range from particular algorithms to problem solvers to constraint based general purpose programming languages. Finally, constraint satisfaction is applied to logic programming and theorem proving. It is shown that incorporating constraint solving in definite clause programs enhances their expressive power. Also, an alternative semantics - based on constraint satisfaction - is given for theorem proving. / Master of Science
317

Is firm-level political risk priced in the equity option market?

Ho, Thang, Kagkadis, A., Wang, G. 20 September 2023 (has links)
Yes / We find a negative relation between firm-level political risk and future delta-hedged equity option returns. A quasi-natural experiment based on Brexit corroborates this finding since after the referendum there is a decrease in the option returns of the positive-Brexit exposure firms. The predictability is driven by the jump risk component of political uncertainty, is more pronounced in periods of high intermediary constraints and is stronger among high-demand pressure options but weaker among politically active firms. Finally, consistent with a risk-based explanation, investors of options on politically risky firms get compensated with high returns when major unexpected political shocks take place.
318

Financing constraints, intellectual property rights protection and incremental innovation: Evidence from transition economy firms

Abdin, J., Sharma, A., Trivedi, Rohit, Wang, Chengang 06 November 2023 (has links)
Yes / Despite a growing literature, the relationship between financing constraints (FC), intellectual property rights (IPR) protection and firm innovation remains unclear within the transitional country context. Drawing on endogenous growth theory and extending the Gorodnichenko and Schnitzer (2013) framework, we hypothesize that in addition to firm-specific factors, country-level variables manifested within FC hamper incremental innovation, albeit in varying degrees due to industry heterogeneity. Secondly, as opposed to previous studies that solely focus on FC affecting firm innovation, we propose that due to resource constraints, firms in transition economies tend to follow an imitational innovation strategy, and therefore, from this perspective, IPR protection can be crucial for firm-level innovation within those economies. Using data from the World Bank Enterprise Survey (WBES) consisting of information for about 21,960 firms from 27 Eastern European and Central Asian transition countries and employing a two-step probit model with endogenous regressors, we find that adverse effects of FC and IPR on firms' innovation activities are driven from within as well as between industries. Focusing on the differential impacts of FC and IPR protection across industries, we direct potential causal pathways from easing FC and optimal IPR protection to encourage firms' innovation. Based on the findings, while very strict IPR protection is detrimental to firms' product and process innovation in industries with limited resource and skill capabilities, it is nevertheless helpful for research and development (R&D) activities in industries characterised by strong R&D and IP capacities. Our results offer useful insights for policymakers to support incremental innovation as well as boost invention. IPR protection policies require to be customised to the industries and firms, since invariably tight or lax IPR enforcement can be discouraging to both incremental and radical innovation, causing all industries suffering from the same treatment.
319

An Activity- Based Costing and Theory of Constraints Model for Product- Mix Decisions

Gurses, Ayse Pinar 14 July 1999 (has links)
The objective of this thesis is to demonstrate the use of the Activity-Based Costing (ABC) approach together with the Theory of Constraints (TOC) philosophy in determining the optimal product-mix and restrictive bottlenecks of a company. The contribution of this thesis is a new product-mix decision model that uses activity-based cost information. This new model is proposed to be used with the TOC philosophy in order to improve the financial performance of a company.</p> Four case studies, all of which are based on hypothetical data, are prepared in this research to show the applicability of the proposed model in different manufacturing environments. Specifically, the first case study shows that the conventional product-mix decision model and the model developed in this thesis can give significantly different results regarding the best product-mix and associated bottlenecks of a company. The second case study demonstrates the use of the proposed product-mix decision model in a complex manufacturing environment. Specifically, this case study shows how companies should consider alternatives such as activity flexibility and outsourcing to improve their profitability figures. The third case study is an extension of the second case study, and it is prepared to illustrate that the proposed model can be extended to include more than one time period. The final case study demonstrates the applicability of the proposed model in a lean manufacturing environment.</p> Using the proposed model developed in this research will give managers more accurate information regarding the optimum product-mix and critical bottlenecks of their companies. By applying the TOC philosophy based on this information, managers will be able to take the right actions that will improve the profitability of their companies. Specifically, they will be able to observe the effects of several alternatives, such as activity flexibility and outsourcing, on the throughput of the whole system. In addition, the proposed model should help managers to prevent making decisions that sub-optimize the system. This may occur, for example, when using only the most efficient methods to produce each product even though the capacities of these methods are limited and some other less efficient methods are currently available in the company. By extending the model to include more than one time period, managers will be able to estimate the potential bottlenecks and the amount of idle capacities of each non-bottleneck activity performed in the company ahead of time. This information is powerful and can give companies a substantial advantage over their competitors because the users of the new model will have enough time to improve the performance of their potential bottlenecks and to search for more profitable usage of excess capacities before the actual production takes place. / Master of Science
320

Quality constraint approach : a six sigma / throughput approach in manufacturing to achieve company success and continuous improvement

Sierra, Jose E. 01 April 2003 (has links)
No description available.

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