Detrimental effects of interventions with the corporate governance mechanisms of young entrepreneurial firms

The purpose of this study is to assess the post-IPO performance structures of young entrepreneurial firms. Based on the propositions of the signaling model, I propose that the firm IPO performance is a determining factor in post-IPO changes in ownership structures. Furthermore, I contend that the new owners that replace the original ones in young IPO firms will be prone to request changes in corporate governance mechanisms such as top management team membership and the boards of directors based on the need to have their own agents looking after their interests as recommended by the agency theory. Following these alterations in corporate governance mechanisms, I propose such changes will be detrimental for the performance of the young entrepreneurial firms as these firms, due to their uniqueness, are still in great need of the tacit knowledge provided by their original decision makers. Finally, moderating effects of the environmental dimensions of dynamism, complexity and munificence are hypothesized to impact the relationship between the rate of change on corporate governance mechanisms and firm performance. In the literature review section I review studies that explore why firms go public, the main areas of IPO research, the importance of executives and directors in young entrepreneurial firms, the theories related to IPO performance and its measures, the uniqueness of these firms and the potential impact of environment on decision making routines. I develop a model that explains the interrelated relationships I propose to be present and the corresponding hypotheses. Using the SDC database, I identified 185 young entrepreneurial firms that went public in 2001, 2002, 2003, 2004 and 2005. Based on the previous literature, the criterion I used for being a young entrepreneurial firm was the founding date. Firms that were founded in 1991 and forward were included in this study. Using the Edgar Database, Compustat Research Insight, CRSP, Disclosures, and the company websites, I compiled a database that consists of stock performance, operating performance, and the governance data for these companies for the five years following their IPOs. The results revealed that one of the IPO performance measures, underpricing, impacts subsequent changes in blockholder ownership in young entrepreneurial firms. Following the changes in ownership structure, the new owners tend to request changes in one of the corporate governance mechanisms I considered, boards of directors, but not top management teams (TMT). I also observed a negative impact for changes in boards of directors on subsequent firm performance when accounting-based measures are considered; this was not the case with TMTs. Furthermore, the results also showed that two of the environmental dimensions exacerbated the relationship between the changes in corporate governance mechanisms and firm performance. These results implied that young entrepreneurial firms operating in complex and less munificent environments are in more need of the inputs provided by their original directors. The study ends with a discussion of the theoretical and managerial implications of the findings together with the specification of possible future extensions and limitations

Enantiospecific Detection of Chiral Nanosamples Using Photoinduced Force

We propose a high-resolution microscopy technique for enantiospecific detection of chiral samples down to sub-100-nm size based on force measurement. We delve into the differential photoinduced optical force ΔF exerted on an achiral probe in the vicinity of a chiral sample when left and right circularly polarized beams separately excite the sample-probe interactive system. We analytically prove that ΔF is entangled with the enantiomer type of the sample enabling enantiospecific detection of chiral inclusions. Moreover, we demonstrate that ΔF is linearly dependent on both the chiral response of the sample and the electric response of the tip and is inversely related to the quartic power of probe-sample distance. We provide physical insight into the transfer of optical activity from the chiral sample to the achiral tip based on a rigorous analytical approach. We support our theoretical achievements by several numerical examples highlighting the potential application of the derived analytic properties. Lastly, we demonstrate the sensitivity of our method to enantiospecify nanoscale chiral samples with chirality parameter on the order of 0.01 and discuss how the sensitivity of our proposed technique can be further improved

Magnetism and correlations in fractionally filled degenerate shells of graphene quantum dots

When an electron is confined to a triangular atomic thick layer of graphene [1-5] with zig-zag edges, its energy spectrum collapses to a shell of degenerate states at the Fermi level (Dirac point) [6-9]. The degeneracy is proportional to the edge size and can be made macroscopic. This opens up the possibility to design a strongly correlated electronic system as a function of fractional filling of the zero-energy shell, in analogy to the fractional quantum Hall effect in a quasi-two-dimensional electron gas[10], but without the need for a high magnetic field. In this work we show that electronic correlations, beyond the Hubbard model[6,7] and mean-field density functional theory (DFT) [7,8] play a crucial role in determining the nature of the ground state and the excitation spectrum of triangular graphene quantum dots as a function of dot size and filling fraction of the shell of zero-energy states. The interactions are treated by a combination of DFT, tight-binding, Hartree-Fock and configuration interaction methods (TB-HF-CI) and include all scattering and exchange terms within second nearest neighbors as well as interaction with metallic gate. We show that a half filled charge neutral shell leads to full spin polarization of the island but this magnetic moment is completely destroyed by the addition of a single electron, in analogy to the effect of skyrmions on the quantum Hall ferromagnet [11-14] and spin depolarization in electrostatically defined semiconductor quantum dots[15-18]. The depolarization of the ground state is predicted to result in blocking of current through a graphene quantum dot due to spin blockade (SB) [18].Comment: v2: minor corrections, new forma

Suppressing Roughness of Virtual Times in Parallel Discrete-Event Simulations

In a parallel discrete-event simulation (PDES) scheme, tasks are distributed among processing elements (PEs), whose progress is controlled by a synchronization scheme. For lattice systems with short-range interactions, the progress of the conservative PDES scheme is governed by the Kardar-Parisi-Zhang equation from the theory of non-equilibrium surface growth. Although the simulated (virtual) times of the PEs progress at a nonzero rate, their standard deviation (spread) diverges with the number of PEs, hindering efficient data collection. We show that weak random interactions among the PEs can make this spread nondivergent. The PEs then progress at a nonzero, near-uniform rate without requiring global synchronizations

Going through Rough Times: from Non-Equilibrium Surface Growth to Algorithmic Scalability

Efficient and faithful parallel simulation of large asynchronous systems is a challenging computational problem. It requires using the concept of local simulated times and a synchronization scheme. We study the scalability of massively parallel algorithms for discrete-event simulations which employ conservative synchronization to enforce causality. We do this by looking at the simulated time horizon as a complex evolving system, and we identify its universal characteristics. We find that the time horizon for the conservative parallel discrete-event simulation scheme exhibits Kardar-Parisi-Zhang-like kinetic roughening. This implies that the algorithm is asymptotically scalable in the sense that the average progress rate of the simulation approaches a non-zero constant. It also implies, however, that there are diverging memory requirements associated with such schemes.Comment: to appear in the Proceedings of the MRS, Fall 200

Synchronization Landscapes in Small-World-Connected Computer Networks

Motivated by a synchronization problem in distributed computing we studied a simple growth model on regular and small-world networks, embedded in one and two-dimensions. We find that the synchronization landscape (corresponding to the progress of the individual processors) exhibits Kardar-Parisi-Zhang-like kinetic roughening on regular networks with short-range communication links. Although the processors, on average, progress at a nonzero rate, their spread (the width of the synchronization landscape) diverges with the number of nodes (desynchronized state) hindering efficient data management. When random communication links are added on top of the one and two-dimensional regular networks (resulting in a small-world network), large fluctuations in the synchronization landscape are suppressed and the width approaches a finite value in the large system-size limit (synchronized state). In the resulting synchronization scheme, the processors make close-to-uniform progress with a nonzero rate without global intervention. We obtain our results by ``simulating the simulations", based on the exact algorithmic rules, supported by coarse-grained arguments.Comment: 20 pages, 22 figure

Non-Destructive Evaluation of Iowa Pavements Phase 2: Development of a Fully Automated Software System for Rapid Analysis/Processing of the Falling Weight Deflectometer Data

The Office of Special Investigations at Iowa Department of Transportation (DOT) collects FWD data on regular basis to evaluate pavement structural conditions. The primary objective of this study was to develop a fully-automated software system for rapid processing of the FWD data along with a user manual. The software system automatically reads the FWD raw data collected by the JILS-20 type FWD machine that Iowa DOT owns, processes and analyzes the collected data with the rapid prediction algorithms developed during the phase I study. This system smoothly integrates the FWD data analysis algorithms and the computer program being used to collect the pavement deflection data. This system can be used to assess pavement condition, estimate remaining pavement life, and eventually help assess pavement rehabilitation strategies by the Iowa DOT pavement management team. This report describes the developed software in detail and can also be used as a user-manual for conducting simulation studies and detailed analyses