Investment during the Korean Financial Crisis: A Structural Econometric Analysis

This paper uses firm-level panel data to analyze the role of financial factors in determining investment outcomes during the Korean financial crisis. Our identification strategy exploits the presence of foreign-denominated debt to measure shocks to the financial position of firms following the devaluation that occurred during the crisis period. Structural parameter estimates imply that financial factors may account for 50% to 80% of the overall drop in investment observed during this episode. Our estimates also imply that foreign-denominated debt had relatively little effect on aggregate investment spending. Counterfactual experiments suggest sizeable contractions in investment through this mechanism for economies that are more heavily dependent on foreign-denominated debt however.

Applications of Hydrodynamic Cavitation in Dairy Manufacturing: Process Development and Standardization

The phenomenon of hydrodynamic cavitation involves the formation, growth, and subsequent collapse of bubbles when a given liquid experienced a reduction of pressure below its vapor pressure. The presence of cavitation limits the performance and the safe operation of many machinery and pumps. However, innovation in the design of the hydrodynamic cavitation devices has offered promising applications in the food and dairy industry. Upon collapse of the cavities, the fluid experiences significant mechanical effects (shear and turbulence) as well as instantaneously elevation of the fluid temperature. All these effects can be put to work for mixing, dispersion, particle size reduction, disinfection, and emulsification. In this thesis, the feasibility of using a rotational cavitator for different unit operations was systematic evaluated. The feasibility of hydrodynamic cavitation was evaluated in terms of analysis of cavitation parameters, characterization of the increase in the fluid temperature, microbial efficiency, and emulsification of ice cream mix. The analysis of the cavitator revealed that the velocities generated inside the rotational cavitator are sufficiently high to induce cavitation within the fluid. The development of the cavitation was influenced by the flow rate, speed of the rotor, temperature, and fluid properties. The pressure at which cavitation would first appear was calculated as a function of the operating parameters. The increase in the temperature of the fluid was modeled, showing satisfactory correlation with the experimental data. The increased in the temperature of the fluid due to cavitation was used to develop a process for assisting thermal pasteurization with the idea of reducing the log counts of thermoduric bacteria. The newly developed process can be operated within a wide range of processing conditions (50-300 L h-1, 600-3600 RPM, 70-85°C with residence time from 10-110 s). It was found a 3.5 log reduction of Bacillus coagulans by cavitation followed by thermal treatment, while thermal treatment along yielded a 2.77 log reduction. The hydrodynamic cavitation was applied during the manufacture of ice cream with the idea of reducing the concentration of stabilizers. Particle size of ice cream mix and rheology test was conducted to determine the influence of the stabilizer amounts in ice cream mix. Hydrodynamic cavitation itself reduced the particle size of cream and ice cream mix. Dynamic rheological measurements (strain and frequency sweeps) of ICM indicated increased product stability at a rotation speed of 3600 RPM and flow of 100 L -1. However, the mechanical spectra were considerable different. Imparted viscosities at medium shear rates were at least 2-fold greater compared to formulations homogenized conventionally

Which Companies are More Profitable When Using Data Mining Techniques?

Over the past decade, many organizations have begun to routinely capture huge volumes of historical data describing their operations, products, and customers. The incredible amounts of data can be saved in electronic formats at reasonable costs with the development of latest data processing and storage technologies. The field of data mining addresses the question of how best to use this vast amount of historical data to discover general regularities and improve the process of making decisions. The concept of data mining is gaining acceptance by many companies as a means of seeking higher profits and lower costs. This research will review several important concepts of data mining and will survey many companies through questionnaires. After receiving survey results, the authors will analyze profits/costs effects by data mining while comparing these effects by SIC indexes

Stitching for multi-view videos with large parallax based on adaptive pixel warping

Conventional stitching techniques for images and videos are based on smooth warping models, and therefore, they often fail to work on multi-view images and videos with large parallax captured by cameras with wide baselines. In this paper, we propose a novel video stitching algorithm for such challenging multi-view videos. We estimate the parameters of ground plane homography, fundamental matrix, and vertical vanishing points reliably, using both of the appearance and activity based feature matches validated by geometric constraints. We alleviate the parallax artifacts in stitching by adaptively warping the off-plane pixels into geometrically accurate matching positions through their ground plane pixels based on the epipolar geometry. We also exploit the inter-view and inter-frame correspondence matching information together to estimate the ground plane pixels reliably, which are then refined by energy minimization. Experimental results show that the proposed algorithm provides geometrically accurate stitching results of multi-view videos with large parallax and outperforms the state-of-the-art stitching methods qualitatively and quantitatively

Charge density functional plus UU calculation of lacunar spinel GaM4_4Se8_8 (M = Nb, Mo, Ta, and W)

Charge density functional plus $U$ calculations are carried out to examine the validity of molecular $J_\text{eff}$=1/2 and 3/2 state in lacunar spinel GaM$_4$X$_8$ (M = Nb, Mo, Ta, and W). With LDA (spin-unpolarized local density approximation)$+U$, which has recently been suggested as the more desirable choice than LSDA (local spin density approximation)$+U$, we examine the band structure in comparison with the previous prediction based on the spin-polarized version of functional and with the prototypical $J_\text{eff}$=1/2 material Sr$_2$IrO$_4$. It is found that the previously suggested $J_\text{eff}$=1/2 and 3/2 band characters remain valid still in LDA$+U$ calculations while the use of charge-only density causes some minor differences. Our result provides the further support for the novel molecular $J_\text{eff}$ state in this series of materials, which can hopefully motivate the future exploration toward its verification and the further search for new functionalities

Non-local Correlation Effects in Fermionic Many-Body Systems: Overcoming the Non-causality Problem

Motivated by the intriguing physics of quasi-2d fermionic systems, such as high-temperature superconducting oxides, layered transition metal chalcogenides or surface or interface systems, the development of many-body computational methods geared at including both local and non-local electronic correlations has become a rapidly evolving field. It has been realized, however, that the success of such methods can be hampered by the emergence of noncausal features in the effective or observable quantities involved. Here, we present a new approach of extending local many-body techniques such as dynamical mean field theory (DMFT) to nonlocal correlations, which preserves causality and has a physically intuitive interpretation. Our strategy has implications for the general class of DMFT-inspired many-body methods, and can be adapted to cluster, dual boson or dual fermion techniques with minimal effort.Comment: 6 pages + 5 pages supplemental materia