Institutions and Economic Development: The Case of Korea

JiSoon Lee 서울대학교 경제연구소 1997 經濟論集 Vol.36 No.4

Institution building is essential for economic development. In this regard this paper reviews how institutions were built in Korea since 1960s, how they have contributed toward Korean economic development, and reasons why some of them no longer serve their intended purposes. The paper argues that the government-led development strategy using financial repression to channel resources to the 'desirable' sectors often dominated by Chaebols, though quite successful in the earlier years, began to lose its fruitfulness from the latter of 1980s. The system is now the main hindrance to further development and the ultimate cause for the current Korean economic crisis. The paper argues that Korea needs to overhaul the entire economic management .system and accompanying institutions toward more open, transparent, and rule-based systems and institutions.

Controlling Half-Metallicity of Graphene Nanoribbons by Using a Ferroelectric Polymer

Lee, Yea-Lee,Kim, Seungchul,Park, Changwon,Ihm, Jisoon,Son, Young-Woo American Chemical Society 2010 ACS NANO Vol.4 No.3

<P>On the basis of first-principles computational approaches, we present a new method to drive zigzag graphene nanoribons (ZGNRs) into the half-metallic state using a ferroelectric material, poly(vinylidene fluoride) (PVDF). Owing to strong dipole moments of PVDFs, the ground state of the ZGNR becomes half-metallic when a critical coverage of PVDFs is achieved on the ZGNR. Since ferroelectric polymers are physisorbed, the direction of the dipole field in PVDFs can be rotated by relatively small external electric fields, and the switching between half-metallic and insulating states may be achieved. Our results suggest that, without excessively large external gate electric fields, half-metallic states of ZGNRs are realizable through the deposition of ferroelectric polymers and their electronic and magnetic properties are controllable <I>via</I> noninvasive mutual interactions.</P><P><B>Graphic Abstract</B> <IMG SRC='http://pubs.acs.org/appl/literatum/publisher/achs/journals/content/ancac3/2010/ancac3.2010.4.issue-3/nn9019064/production/images/medium/nn-2009-019064_0004.gif'></P><P><A href='http://pubs.acs.org/doi/suppl/10.1021/nn9019064'>ACS Electronic Supporting Info</A></P>

Manifestation of axion electrodynamics through magnetic ordering on edges of a topological insulator

Lee, Yea-Lee,Park, Hee Chul,Ihm, Jisoon,Son, Young-Woo National Academy of Sciences 2015 PROCEEDINGS OF THE NATIONAL ACADEMY OF SCIENCES OF Vol.112 No.37

<P><B>Significance</B></P><P>Interactions between two adjacent surfaces of different surface orientations in a single-crystal topological insulator are investigated. We show that the edge between two surfaces can host nontrivial axion electrodynamics with sizeable experimental signals owing to the unique interaction between the two topological surface states. We find that the large work function difference between facets in a topological insulator can generate strong electric fields around the edges and that, in turn, the electric fields give rise to effective magnetic fields for a given broken time-reversal symmetry. Our theoretical work highlights a route to reveal intriguing axion electrodynamics in a real solid and provides methods to exploit macroscopic topological states.</P><P>Because topological surface states of a single-crystal topological insulator can exist on all surfaces with different crystal orientations enclosing the crystal, mutual interactions among those states contiguous to each other through edges can lead to unique phenomena inconceivable in normal insulators. Here we show, based on a first-principles approach, that the difference in the work function between adjacent surfaces with different crystal-face orientations generates a built-in electric field around facet edges of a prototypical topological insulator such as Bi<SUB>2</SUB>Se<SUB>3</SUB>. Owing to the topological magnetoelectric coupling for a given broken time-reversal symmetry in the crystal, the electric field, in turn, forces effective magnetic dipoles to accumulate along the edges, realizing the facet-edge magnetic ordering. We demonstrate that the predicted magnetic ordering is in fact a manifestation of the axion electrodynamics in real solids.</P>

An Economic Analysis of the Screening Industry

Jisoon Lee 서울대학교 경제연구소 2009 Seoul journal of economics Vol.22 No.3

Utilizing a simple screening model, we explain how the provision of screening services alters equilibrium allocations of funds. For example, when screening services are available, banks tend to increase funding for risky projects and the equilibrium interest rate tends to fall. Indeed, the former is an increasing and the latter is a decreasing function of the extent of screening. These results accord well with our usual expectation. The proposed model, however, provides an unexpected result: It shows that having the screening industry run by a profit maximizing monopolist might be better than relying on many competing firms. This seemingly unusual result comes from the realization that, when many firms are competing, they produce essentially the same 'products' over and over again, resulting in serious information duplications. A monopoly can easily avoid information duplications. However, it results in deadweight losses. Separating information production businesses from information selling businesses seems to be a better option. We show that when the former is handled by a single public entity and the latter is handled by many competing firms, we can have better outcomes. This arrangement solves the information duplication problem. More importantly, the resulting equilibrium configurations could be made identical to competitive equilibrium outcomes.

Financial Reforms: Benefits and Costs

Jisoon Lee 서울대학교 경제연구소 2006 Seoul journal of economics Vol.19 No.4

Using financial reforms as example, we demonstrate that reform measures should be undertaken only when they have substantial net expected benefits. In most cases, financial reform measures entail substantial upfront fixed costs in return for a steady flow of benefits over a long period of time. The benefits tend to become larger in tandem with the volume of financial transactions. Because of these, it would be easier for wealthier countries to undertake financial reforms: They can afford expensive but better systems. However, poor countries cannot do so easily, because they lack sufficient resources. Consequently poor countries would better take more gradual and pragmatic approaches to financial reforms.

Finance and Economic Activities

Jisoon Lee 서울대학교 경제연구소 1999 Seoul journal of economics Vol.12 No.4

This paper reviews the roles and limits of finance in modern economies. Finance improves the efficiency of resource allocations. It does this by first correcting market failures and second by making markets function better. Finance also contributes toward economic growth and development. Finance does this by making more efficient investments and faster technological progress possible. Finance, when it malfunctions, can bring serious economic disasters. Because of the asymmetry of information inherent in financial transactions, and because of the ability of the most important segment of the financial industry to create credit, finance may break down under certain conditions. When finance breaks down, it can easily bring the entire economy into trouble because finance is so pervasive. Finance can malfunction, too, when the policy environment surrounding the financial markets and systems are so ill-designed as to give them wrong incentives. Here, financial controls used by developing economies often turn out to be the real causes for the breakdown of finance. One of the key reasons why finance may malfunction has to do with poorly working corporate governance mechanisms. When mechanisms governing the behavior of financial institutions and markets, the lenders and the intermediators, do not work properly, the latter are very likely to malfunction. When financial markets and institutions malfunction, they can easily bring trouble to the real economy. When mechanisms governing the corporate sector, the investor-borrowers, do not work properly, the real sector could breakdown. And when the real sector breaks down, financial systems and markets could breakdown, too. The paper also compares different modes of corporate governance being used in Korea, Japan, and America.

Field emission of metal nanowires studied by first-principles methods

Lee, Choong-Ki,Lee, Bora,Ihm, Jisoon,Han, Seungwu IOP Pub 2007 Nanotechnology Vol.18 No.47

<P>We study the field-emission properties of an ultrathin silver nanowire using first-principles methods. The simulation and analysis of the field emission are carried out based on density-functional theory using a localized basis scheme. Through the explicit time evolution of wavefunctions, we obtain the emission currents and spatial distributions of emitted electrons from a silver nanowire. In contrast to carbon nanotubes, the localized states are not found. Instead, pronounced emission currents are observed for s-like extended states that are free of nodes in a plane normal to the field direction, and the total emission currents of a silver nanowire are found to be significantly larger than those of carbon nanotubes. A quantum-mechanical analysis is presented to explain the observed current enhancement. On the other hand, an ultrathin gold nanowire gives much smaller emission currents than the silver nanowire due to a larger work function.</P>

Markov Property and Excess Sensitivity in Aggregate Consumption

Jisoon Lee 서울대학교 경제연구소 1988 Seoul journal of economics Vol.1 No.2

Graphene as a flexible template for controlling magnetic interactions between metal atoms

Lee, Sungwoo,Kim, Dongwook,Robertson, Alex W,Yoon, Euijoon,Hong, Suklyun,Ihm, Jisoon,Yu, Jaejun,Warner, Jamie H,Lee, Gun-Do Institute of Physics 2017 Journal of Physics, Condensed Matter Vol.29 No.8

<P>Metal-doped graphene produces magnetic moments that have potential application in spintronics. Here we use density function theory computational methods to show how the magnetic interaction between metal atoms doped in graphene can be controlled by the degree of flexure in a graphene membrane. Bending graphene by flexing causes the distance between two substitutional Fe atoms covalently bonded in graphene to gradually increase and these results in the magnetic moment disappearing at a critical strain value. At the critical strain, a carbon atom can enter between the two Fe atoms and blocks the interaction between relevant orbitals of Fe atoms to quench the magnetic moment. The control of interactions between doped atoms by exploiting the mechanical flexibility of graphene is a unique approach to manipulating the magnetic properties and opens up new opportunities for mechanical-magnetic 2D device systems.</P>

commentary : ICT, a Stepping-stone for Prosperity

Jisoon Lee 정보통신정책연구원 2008 ICT World Today Vol.1 No.1