Determinants of Family Ownership: The Choice between Control and Performance

This paper analyzes what determines ownership structure of family firms in Korea. Our analysis shows that control is as important a factor as performance in the determination of whether a family in Korea chooses to own a firm. The controlling family prefers to own shares of de facto holding companies because they provide control over affiliated companies and firms that perform well. The family, however, allows its affiliated companies to own more shares of firms that perform poorly and of firms that do not provide the family with power to control the firm. In addition, controlling families own fewer shares of firms that make bond investments in affiliated companies because bond holding does not provide control. We carry out logit regressions for firms without family ownership and for firms with a positive family ownership. The family chooses not to own shares regardless of a firm's performance if the firm does not provide significant control over affiliated companies. We also show that the family values its control more for closely held firms.

The Choice of Group Structure: Divide and Rule

This paper concerns the structure of Korean business groups. We investigate the factors that affect a controlling shareholder's decision regarding the structure of his business group and the location of its member firms, using financial and ownership data on conglomerate groups in Korea. We define new measures that represent the levels of vertical and circuitous structures of a group, and the location of member firms in the group. We empirically confirm that controlling shareholders strategically choose the structure of their business groups to secure control over the groups and to seek private benefit of control. The risk diversification and propping incentive of controlling shareholders is also found to affect the decisions.

Regulatory guideline for biosimilar products in Korea

AbstractThe regulatory framework of biosimilar products in Korea is a 3-tiered system: 1) Pharmaceutical Affairs Act; 2) Notification of the regulation on review and authorization of biological products; 3) Guideline on evaluation of biosimilar products. A biosimilar product is regulated under the same regulation as biological products. The difference from new biological product is that biosimilar product requires full comparability data with reference product. Based on these data, some of the non-clinical and clinical data could be abbreviated. As Korean guideline for biosimilar products was developed along with that of the WHO’s, most of the recommendations were based on similar principle except the clinical evaluation to demonstrate similarity. No biosimilar products are licensed yet, however, 4 IND products have been approved for phase I or III clinical trials. The addressed issues during review were as follows: acceptability of reference products manufactured in different sites, determination of acceptable criteria for differences and selection of analytical tests for the comparability exercise to detect potential differences in quality attributes, relevant species for non-clinical study, and duration of toxicity study, etc. These and other future issues will be dealt with scientific advancement, experiences of collaborating work with WHO or other NRAs, which will be reflected in the guidelines on regulations of biosimilar products in Korea

Separation of incident and reflected waves in wave-current flumes

author's final versionA technique is developed to separate the incident and reflected waves propagating on a known current in a laboratory wave-current flume by analyzing wave records measured at two or more locations using a least squares method. It can be applied to both regular and irregular waves. To examine its performance, numerical tests are made for waves propagating on quiescent or flowing water. In some cases, to represent the signal noise and measurement error, white noise is superimposed on the numerically generated wave signal. For all the cases, good agreement is observed between target and estimation

Wave Reflection from Partially-Perforated-Wall Caisson Breakwater

In 1995, Suh and Park developed a numerical model that computes the reflection of regular waves from a fully-perforated-wall caisson breakwater. This paper describes how to apply this model to a partially-perforated-wall caisson and irregular waves. To examine the performance of the model, existing experimental data are used for regular waves, while a laboratory experiment is conducted in this study for irregular waves. The numerical model based on a linear wave theory tends to over-predict the reflection coefficient of regular waves as the wave nonlinearity increases, but such an over-prediction is not observed in the case of irregular waves. For both regular and irregular waves, the numerical model slightly over- and under-predicts the reflection coefficients at larger and smaller values, respectively, because the model neglects the evanescent waves near the breakwater.author's final versio

Corporate Governance, Product Market Competition, and Payout Policy

This paper investigates how the interaction between internal corporate governance and product market competition affects corporate payout. Empirically, existing papers demonstrate that corporate governance has a significantly negative effect on corporate payout; however, we observe that this negative relation is observed only in less competitive (concentrated) markets, and disappears or decreases in more competitive markets. The result suggests that the substitution effect between internal corporate governance and product market competition in the effect on firm value, as suggested in previous literatures, is also valid in payout policy. Our results will provide practical and institutional implications regarding the most efficient method of finding optimal internal corporate governance structure given market structures

Experimental verification of horizontal two-dimensional modified mild-slope equation model

In order to verify modified mild-slope equation models in a horizontal two-dimensional space, a hydraulic experiment is made for surface wave propagation over a circular shoal on which water depth varies substantially. A horizontal two-dimensional numerical model is also constructed based on the hyperbolic equations that have been developed from the modified mild-slope equation to account for the substantial depth variation. Comparison between experimental measurements and numerical results shows that the modified mild-slope equation model is capable of producing accurate results for wave propagation in a region where water depth varies substantially, while the conventional mild-slope equation model gives large errors as the mild-slope assumption is violated.author's final versio

Gardenia jasminoides

Ultraviolet radiation (UV) is a major cause of photoaging, which also involves inflammatory cytokines and matrix metalloproteinases (MMP). The present study was undertaken to examine the UVB-protecting effects of yellow-colored plant extracts in cell-based assays. HaCaT keratinocytes were exposed to UVB in the absence or presence of plant extracts, and resulting changes in cell viability and inflammatory cytokine expression were measured. Of the plant extracts tested, Gardenia jasminoides extract showed the lowest cytotoxicity and dose-dependently enhanced the viabilities of UVB-exposed cells. Gardenia jasminoides extract also attenuated the mRNA expressions of interleukin-1β (IL-1β) and tumor necrosis factor-α (TNF-α) in HaCaT cells stimulated by UVB. Conditioned medium from UVB-exposed HaCaT cells was observed to stimulate MMP-1 protein expression in human dermal fibroblasts, and this effect was much smaller for the conditioned medium of HaCaT cells exposed to UVB in the presence of Gardenia jasminoides extract. Gardenia jasminoides extract also exhibited antioxidative and antiapoptotic effects in HaCaT cells exposed to UVB. These results indicated that UVB-induced injury and inflammatory responses of skin cells can be attenuated by yellow-colored plant extracts, such as Gardenia jasminoides extract

Scattering of irregular waves by vertical cylinders

author's final versionAn analytical model has been developed that can predict the scattering of irregular waves normally incident upon an array of vertical cylinders. To examine the predictability of the developed model, laboratory experiments have been made for the reflection and transmission of irregular waves from arrays of circular cylinders with various diameters and gap widths. Though the overall agreement between measurement and calculation is fairly good, the model tends to over- and under-predict the reflection and transmission coefficients, respectively, as the gap width decreases. The model also underestimates the energy loss coefficients for small gap widths because it neglects the evanescent waves near the cylinders. The peaks of the measured spectra of the reflected and transmitted waves slightly shift towards higher frequencies compared with that of the incident wave spectrum probably because of the generation of shorter period waves due to the interference of the cylinders. Both model and experimental data show that the wave reflection and transmission become larger and smaller, respectively, as the wave steepness increases, which is a desirable feature of the cylinder breakwaters