Modeling of the excited modes in inverted embedded microstrip lines using the finite-difference time-domain (FDTD) technique

This thesis investigates the presence of multiple (quasi-TEM) modes in inverted embedded microstrip lines. It has already been shown that parasitic modes do exist in inverted embedded microstrips due to field leakage inside the dielectric substrate, especially for high dielectric constants (like Silicon). This thesis expands upon that work and characterizes those modes for a variety of geometrical dimensions. Chapter 1 focuses on the theory behind the different transmission line modes, which may be present in inverted embedded microstrips. Based on the structure of the inverted embedded microstrip, the conventional microstrip mode, the quasi-conventional microstrip mode, and the stripline mode are expected. Chapter 2 discusses in detail the techniques used to decompose the total probed field into the various modes present in the inverted embedded microstrip lines. Firstly, a short explanation of the finite-difference time-domain method, that is used for the simulation and modeling of inverted microstrips up to 50 GHz is provided. Next, a flowchart of the process involved in decomposing the modes is laid out. Lastly, the challenges of this approach are also highlighted to give an appreciation of the difficulty in obtaining accurate results. Chapter 3 shows the results (dispersion diagrams, values/percentage of the individual mode energies ) obtained after running time-domain simulations for a variety of geometrical dimensions. Chapter 4 concludes the thesis by explaining the results in terms of the transmission line theory presented in Chapter 1. Next, possible future work is mentioned.M.S.Committee Chair: Tentzeris, Emmanouil; Committee Member: Andrew Peterson; Committee Member: Laskar, Joy; Committee Member: Papapolymerou, Ioanni

Social Learning with Payoff Complementarities

We incorporate strategic complementarities into a multi-agent sequential choice model with observable actions and private information. In this framework agents are concerned with learning from predecessors, signalling to successors, and coordinating their actions with those of others. Coordination problems have hitherto been studied using static coordination games which do not allow for learning behavior. Social learning has been examined using games of sequential action under uncertainty, but in the absence of strategic complementarities (herding models). Our model captures the strategic behavior of static coordination games, the social learning aspect of herding models, and the signalling behavior missing from both of these classes of models in one unified framework. In sequential action problems with incomplete information, agents exhibit herd behavior if later decision makers assign too little importance to their private information, choosing instead to imitate their predecessors. In our setting we demonstrate that agents may exhibit either strong herd behavior (complete imitation) or weak herd behavior (overoptimism) and characterize the informational requirements for these distinct outcomes. We also characterize the informational requirements to ensure the possibility of coordination upon a risky but socially optimal action in a game with finite but unboundedly large numbers of players.

Strategi Pemerintah Desa Sesaot Guna Pengembangan Obyek Wisata Berbasis Masyarakat (Community Based Toursm)

The tourism industry movement in Sesaot Village needs to be more vibrant. Apart from being weak in the field of promotion, the sluggish tourism industry in the local area is also due to inadequate empowerment in community involvement and the lack of existing facilities and infrastructure in the tourist area of Sesaot Village. The quality of human resources (HR) ready to manage the tourism industry is still limited. This study aims to describe; (1) find out how the village government's strategy is in developing community-based tourism objects (Community-Based Tourism); (2) find out what factors inhibit the village government's strategy in developing community-based tourism objects (Community-Based Tourism). This study uses a descriptive qualitative approach to determine informants using a purposive technique. Data was obtained using in-depth interviews, observation, and documentation. The results of the study show that the Sesaot Village Government has a goal of developing community-based tourism objects in order to improve the economy and welfare of the local community. The strategy to be carried out is to involve the community in developing tourism objects by building good communication and facilitating community participation in each stage of development, building basic infrastructure such as roads, clean water, sanitation, and electricity to increase the comfort of tourists and strengthen village structures, encouraging the formation of groups community businesses engaged in the tourism sector to manage and promote tourism objects, improve the quality of tourism products by providing training and assistance in terms of service, security, and visitor comfort, utilizing information and communication technology to promote tourism objects

Estimating Lost Output from Allocative Inefficiency, with an Application to Chile and Firing Costs

We propose a new measure of allocative efficiency based on unrealized increases in aggregate productivity growth. We show that the difference in the value of the marginal product of an input and its marginal cost at any plant - the plant-input "gap" - is exactly equal to the change in aggregate output that would occur if that plant changed that input's use by one unit. The mean absolute gap across plants for any input can then be interpreted as an approximation to the gain to society that would occur if every plant had a one-unit change in that input in the efficient direction, holding everything else constant. We show how to estimate this average gap using plant-level data for 1982-1994 from Chilean manufacturing, a sector largely viewed as being one of South America's least distorted. We find the gaps for blue and white collar labor are quite large in absolute value and imply that a one-unit move in the correct direction for blue collar would increase aggregate value added by almost 0.5%. We also find that the gaps for blue and white collar workers are increasing over time while the gaps for materials and electricity are not. The timing of the two separate increases in firing costs and the sharpest increases in the labor gaps is suggestive that the increases in average within-firm labor gaps may be related to the increases in severance pay.

The Wall Street Walk when Blockholders Compete for Flows

Publicly traded corporations are a¤ected by a core agency problem: managers pay the full cost of e¤ort in running the corporations but shareholders enjoy most of the bene?ts. When ownership is dispersed individual shareholders have little incentive to monitor managers and little ability to in?uence them. Holders of equity blocks (?blockholders?) are a natural solu- tion to this problem. Because they own many shares they have both the incentive to monitor and the ability to in?uence management. Several well-known papers (e.g. Grossman and Hart (1980), Shleifer and Vishny (1986), Admati, P?eiderer, and Zechner (1994) and Kahn and Winton (1998)) have shown that blockholders can increase ?rm value through monitoring and activism. Activism can take the form of bringing forth shareholder proposals, proxy voting against management, informal negotiations with management, jawboning etc. These activities are collectively referred to as the use of ?voice?by blockholders.

Job Security Does Affect Economic Efficiency: Theory, A New Statistic, and Evidence from Chile

The extensive empirical macro- and micro-level evidence on the impact of job security provisions is largely inconclusive. We argue that the weak evidence is a consequence of the weak power of statistics used, which is suggested by a dynamic theory of plant-level labor demand that we develop. This model speaks clearly on one issue: firing costs drive a wedge between the marginal revenue product of labor and its marginal cost. We examine changes in this gap as our test statistic. It is easy to compute and has a welfare interpretation. We use census data of Chilean manufacturing firms for the years 1979-1996 to look for real effects induced by two significant increases in the costs of dismissing employees. Similar to previous findings in other data, the traditional labor demand statistics provide little evidence of a negative impact from increases in firing costs. While we find no evidence that gaps increase for inputs that are not directly affected by firing costs, we find large and statistically significant increases in the mean and variance of the within-firm gap between the marginal revenue product of labor and the wage for both blue and white collar workers.

Financial equilibrium with career concerns

What are the equilibrium features of a financial market where a sizeable proportion of traders face reputational concerns? This question is central to our understanding of financial markets, which are increasingly dominated by institutional investors. We construct a model of delegated portfolio management that captures key features of the US mutual fund industry and embed it in an asset pricing framework. We thus provide a formal model of financial equilibrium with career concerned agents. Fund managers differ in their ability to understand market fundamentals, and in every period investors choose a fund. In equilibrium, the presence of career concerns induces uninformed fund managers to churn , i.e., to engage in trading even when they face a negative expected return. Churners act as noise traders and enhance the level of trading volume. The equilibrium relationship between fund return and net fund flows displays a skewed shape that is consistent with stylized facts. The robustness of our core results is probed from several angles.Career concerns, financial equilibrium, trade volume

Measuring Aggregate Productivity Growth Using Plant-Level Data

We define productivity growth as the change in welfare that arises from additional output holding primary inputs constant. Using this traditional growth-accounting definition, we show that gains may arise because of plant-level technology shocks, and, in imperfectly competitive settings, from the reallocation of inputs across plants with differing markups and/or shadow values of primary inputs. With plant-level data, the alternative and most popular definition of productivity growth looks at the difference in the first moments of the productivity distribution. We show that this definition adds an additional term to the growth-accounting measure, which has been called “reallocation.” We show there is a very weak relationship between the two indexes in almost every 3-digit manufacturing industry in both Chile from 1987-1996 and Colombia from 1981-1991 - 49 in total - primarily because this “reallocation” term is large and volatile. We explore the theoretical reasons for this sharp divergence, in the process uncovering a number of previously unnoticed and unattractive features of the first-moment definition. For example, it is not tethered to any theoretical model, it is sensitive to measured units, and it can report positive productivity growth when welfare has fallen.