Showing papers by "Korea University published in 1994"
TL;DR: In this article, the authors extended Hamilton's Markov-switching model to a general state-space model and proposed a filtering and smoothing algorithm to estimate a broad class of models.
1,456 citations
TL;DR: This article found that female educational attainment has a pronounced negative effect on fertility, whereas female and male educational attainment are each positively related to life expectancy and negatively related to infant mortality, and male attainment plays a positive role in primary-school enrollment ratios, and female attainment relate positively to enrollment at the secondary level.
1,072 citations
Posted Content•
TL;DR: In this article, the effect of foreign direct investment on economic growth in a cross-country regression framework, utilizing data on FDI flows from industrial countries to 69 developing countries over the last two decades.
Abstract: We test the effect of foreign direct investment (FDI) on economic growth in a cross-country regression framework, utilizing data on FDI flows from industrial countries to 69 developing countries over the last two decades. Our results suggest that FDI is an important vehicle for the transfer of technology, contributing relatively more to growth than domestic investment. However, the higher productivity of FDI holds only when the host country has a minimum threshold stock of human capital. In addition, FDI has the effect of increasing total investment in the economy more than one for one, which suggests the predominance of complementarity effects with domestic firms.
729 citations
Posted Content•
TL;DR: In this paper, the authors present an endogenous growth model of an open economy in which the growth rate of income is higher if foreign capital goods are used relatively more than domestic capital goods for the production of capital stock.
Abstract: This paper presents an endogenous growth model of an open economy in which the growth rate of income is higher if foreign capital goods are used relatively more than domestic capital goods for the production of capital stock. Empirical results, using cross country data for the period 1960-85, confirm that the ratio of imported to domestically produced capital goods in the composition of investment has a significant positive effect on per capita income growth rates across countries, in particular, in developing countries. Hence, the composition of investment in addition to the volume of total capital accumulation is highlighted as an important determinant of economic growth.
382 citations
TL;DR: It is shown that if knowledge of the domain is available, it is exploited by the genetic algorithm leading to an even better performance of the fuzzy controller.
Abstract: The successful application of fuzzy reasoning models to fuzzy control systems depends on a number of parameters, such as fuzzy membership functions, that are usually decided upon subjectively. It is shown in this paper that the performance of fuzzy control systems may be improved if the fuzzy reasoning model is supplemented by a genetic-based learning mechanism. The genetic algorithm enables us to generate an optimal set of parameters for the fuzzy reasoning model based either on their initial subjective selection or on a random selection. It is shown that if knowledge of the domain is available, it is exploited by the genetic algorithm leading to an even better performance of the fuzzy controller. >
291 citations
Posted Content•
TL;DR: This article examined the political and economic determinants of non-tariff barriers, as well as the impact of protection on trade flows, and found that even after accounting for industry-specific factors, nations tend to protect industries that are weak, in decline and threatened by import competition.
Abstract: We use disaggregated data on trade flows, production, and trade barriers for 41 countries in 1988 to examine the political and economic determinants of non-tariff barriers, as well as the impact of protection (both tariff and non-tariff) on trade flows. We use an econometric framework that allows for the simultaneous detennination of trade barriers and trade flows. Our results are consistent with political-economy theories of the determinants of protection: even after accounting for industry-specific factors, nations tend to protect industries that are weak, in decline, and threatened by import competition. Countries also give more protection to large industries; these might be thought of as politically important. Nations use tariffs, non-tariff barriers, and exchange rate controls as complementary instruments of protection.
235 citations
TL;DR: In this paper, the political and economic determinants of nontariff barriers, as well as the impact of protection on trade flows are examined. But, the results are consistent with political-economy theories of the determinant of protection: nations tend to protect industries that are weak, in decline, politically important, or threatened by import competition, but provide less protection to industries in which exports are important.
Abstract: We use disaggregated data on trade flows, production, and trade barriers for 41 countries in 1988 to examine the political and economic determinants of nontariff barriers, as well as the impact of protection (both tariff and nontariff) on trade flows. We use an econometric framework that allows for the simultaneous determination of trade barriers and trade flows. Our results are consistent with political-economy theories of the determinants of protection: even after accounting for industry- and country-specific factors, nations tend to protect industries that are weak, in decline, politically important, or threatened by import competition, but provide less protection to industries in which exports are important.
218 citations
TL;DR: In this article, the authors measured the elastic light vector meson cross sections at an average υp center of mass energy of 180 GeV with the ZEUS detector at HERA.
Abstract: Photon proton cross sections for elastic light vector meson production, σelνp, inelastic diffractive production, σndνp, non-diffractive production, σdνp, as well as the total cross section, σtotνp, have been measured at an average υp center of mass energy of 180 GeV with the ZEUS detector at HERA. The resulting values are σelνp = 18 ± 7 μb, σdνp = 33 ± 8 μb, σndνp = 91 ± 11 μb, and σtotνp 143 ± 17 μb, where the errors include statistical and systematic errors added in quadrature.
169 citations
TL;DR: It is found that several epitopes defined by monoclonal antibodies to the G2 protein were highly conserved as detected by HAI tests and ELISA, and almost all of the isolates could be neutralized by at least one G2-specific monOClonal antibody.
163 citations
TL;DR: In this paper, the phase behavior of the ternary system can be better predicted by the Patel-Teja equation of state with the Adachi and Sugie mixing rule than with the three other mixing rules, though the concentration is not estimated satisfactorily.
Abstract: For applications related to the use of supercritical C02 to concentrate ethanol solutions from a fermentation broth, vapor-liquid equilibria for the CO 2 C 2 H 5 OH and the CO 2 C 2 H 5 OHH 2 O system were measured at 313.2, 323.2, 333.2, and 343.2 K at pressures up to 18.5 MPa over a wide range of ethanol concentration. A circulation type of equilibrium apparatus in which both vapor and liquid phases were continuously recirculated was adopted for measurements. Using C02, aqueous ethanol can be concentrated above atmospheric azeotropic composition (89.4 mol %) when the pressure in the ternary system CO 2 C 2 H 5 OHH 2 O is below the critical pressure of the binary system CO 2 C 2 H 5 OH. The experimental measurements for the phase equilibria were compared with the results predicted by Patel-Teja equation of state using each one of the four types of mixing rules: conventional, Wilson, Yu et al., and Adachi and Sugie. Good estimation was obtained for the phase equilibria of the binary systems except for the conventional mixing rule. It was also found that the phase behavior of the ternary system can be better predicted by the Patel-Teja equation of state with the Adachi and Sugie mixing rule than with the three other mixing rules, though the concentration is not estimated satisfactorily.
105 citations
TL;DR: In this paper, the authors examined O'Reilly and Chatman's compliance, identification, and internalization scales, and compared the latter measures to the OCQ, concluding that the internalization measure was more consistent with OCQ than the identification measure.
TL;DR: A measure called the satisfaction function is proposed which estimates the satisfaction degree of arithmetic comparison relations (such as >, >) and it is shown that the degree of satisfaction is higher on the positive side than the negative side.
TL;DR: The present model offers several advantages in performing behavioral tests: it is easy to apply thermal stimulation to the rat's tail using a water bottle; it iseasy to apply the mechanical stimulation with von Frey hairs and to localize sensitive areas in the tail; and blind behavioral studies are possible due to the lack of deformity in the tails after surgery.
TL;DR: In this paper, the authors present differential scanning calorimetry, optical and X-ray diffraction measurements for a new dimesogenic liquid crystal compound (KI5), which includes new smectic phases and rare phase transitions.
Abstract: We present differential scanning calorimetry, optical and X-ray diffraction measurements for a new dimesogenic liquid crystal compound (KI5). The rich polymorphism of this compound includes new smectic phases and rare phase transitions. In particular the first observation in a pure compound of two incommensurate SA phases as well as cholesteric and helical smectic phases (TGB and SC * phases) are reported. We discuss this observation in terms of the dual peculiar structural character of the molecule: a polyphilic and dimesogenic system including the concept of the central flexible spacer
TL;DR: In this paper, a non-random lattice fluid theory was derived based on the Helmholtz free energy from the full Guggenheim combinatory with vacant sites around the reference athermal solution.
TL;DR: In this article, the semantics of Korean common nouns in light of Link's (1983) semantic theory on denotations of plurals and mass terms were analyzed in Korean.
Abstract: In this paper, I try to present the semantics of Korean common nouns in light of Link's (1983) semantic theory on denotations of plurals and mass terms. First, I show that the semantic count/mass distinction of common nouns is as important in Korean as in English, despite the fact that the distinction is blurred in some constructions such as the canonical quantification structure of [CN(Nominal) + Numeral + Classifier]. Then, the semantic domains of Korean count nouns are shown to be much like those of English count nouns except that the denotation of a syntactically singular count noun in Korean may include a semantically plural domain as well as a singular domain. For instance, using Link's Logic of Plurals and Mass Terms,sakwa in Korean denotes |*apple'|, rather than |apple'|, the latter being the denotation of Englishapple. It is also shown that the semantic domains of common nouns, in Korean and even in English in some cases, are much more flexible than may be thought. This claim is made with respect to the proportional reading of Englishmany (discussed by Partee (1988)) and Koreanmanhun. In this connection, a possible semantic treatment of Korean classifiers as domain shifters is provided. This enables us to capture our semantic intuition about anomalous expressions such aschayk ‘book’,han ‘one’, and the classifiercan ‘glass’. Finally, some problems closely related to the interpretation of common nouns, namely the problems of kinds, genericity, and topicality, are discussed. It is shown how these notions are related in the theory which allows flexible interpretive domains of common nouns.
TL;DR: In this paper, the effects of such constituents as the crosslinked part, non-crosslinked LDPE part, antioxidant, and residual byproducts on the formation of space charge in XLPE have been investigated.
Abstract: The effects of such constituents as the crosslinked part, non-crosslinked LDPE part, antioxidant, and residual byproducts on the formation of space charge in XLPE have been investigated. It has been found that homocharge is developed in the pure crosslinked part of XLPE. The non-crosslinked LDPE part encourages the formation of heterocharge, although its influence is not strong. Residual byproducts generated during the crosslinking reaction encourage the formation of heterocharge, whereas antioxidant was found to prohibit the formation of heterocharge. Of these, residual byproducts have been found to impose the most pronounced influence on the formation of heterocharge in XLPE, so that only heterocharge is found in an as-pressed XLPE with semiconductive electrodes. >
TL;DR: In this paper, a di-jet sample of the ZEUS detector for photoproduction events was used to study resolved photon interactions and cross sections for the resolved and direct processes were given in a restricted kinematic range.
TL;DR: Most basic isoforms of β-1,3-glucanases were induced and accumulated in both the compatible and incompatible interactions, suggesting a possible involvement of the hydrolases in the infection process rather than in the resistance expression.
TL;DR: The chondrite-normalized rare-earth element (REE) patterns of leuco-granitic gneiss and its constituent minerals exhibit the tetrad phenomenon which suggests a special event related to aqueous activity.
TL;DR: In this article, a nonrandom lattice fluid model was derived and applied to pure fluids in which an explicit expression for thermodynamic properties were obtained by expanding Helmholtz free energy and the nonrandomness factor around the reference athermal solution.
TL;DR: It is suggested that CS infection to hamsters may have a promoting effect on the development of CHCA.
Abstract: Chronic Clonorchis sinensis (CS) infection is etiologically related to cholangiocarcinoma (CHCA) in human and animals. This study was carried out to clarify the role of CS infection on dimethylnitrosamine (DMN)-induced cholangiocarcinogenesis. Fifteen hamsters were administered with 15 ppm DMN for 4 weeks and one week later, the hamsters were infected with 15 metacercariae of CS (DMN-->CS group). The other 15 hamsters were infected with CS and after 5 weeks they were treated with the drug, praziquantel. Again one week later, the hamsters were administered with DMN (CS-->DMN group). The other 15 hamsters were administered with DMN and CS simultaneously (CS+DMN group). Histopathological examination of the livers showed CHCA with papillary or adenomatous hyperplasia of bile ductules in 3 of 15 hamsters of DMN-->CS group and in 11 of 15 hamsters of DMN+CS group. These results suggest that CS infection to hamsters may have a promoting effect on the development of CHCA.
TL;DR: The Hwanggangri mineralized district is located approximately 130 km southeast of Seoul within the Paleozoic Ogcheon belt of South Korea as discussed by the authors, and the Jungbo, Suri, and Deogman mines in the district occur around the Late Cretaceous (whole-rock K-Ar age = 89.04 + or - 1.95 Ma) Susan Granite and are located on W-Mo-bearing quartz veins.
Abstract: The Hwanggangri mineralized district is located approximately 130 km southeast of Seoul within the Paleozoic Ogcheon belt of South Korea. The Jungbo, Suri, and Deogman mines in the district occur around the Late Cretaceous (whole-rock K-Ar age = 89.0 + or - 2.0 Ma) Susan Granite and are located on W-Mo-bearing quartz veins. These veins fill fractures in the granite and its host rocks which comprise early Paleozoic limestone-rich sedimentary rocks. The K-Ar date of vein muscovite (88.58 + or - 1.95 Ma) is very similar to that of the Susan Granite (89.04 + or - 1.95 Ma), indicating that W-Mo mineralization was associated with intrusion of the granite. Molybdenite- and wolframite-rich deposits occur within or near ( 285 degrees C from H 2 O-CO 2 fluids with salinities of 0.4 to 9.7 wt percent NaCl equiv, probably in response to pH increase due to boiling (including CO 2 unmixing) of the hydrothermal fluid at pressures between 150 and 220 bars. Following W-Mo deposition, the high-temperature fluids gave way to progressively cooler, more dilute fluids associated with scheelite-base metal sulfide deposition (200 degrees -320 degrees C, 0.7-7.2 wt % NaCl equiv) and carbonate-fluorite deposition (105 degrees -225 degrees C, 0.0-3.2 wt % NaCl equiv). These trends are interpreted as the result of progressive mixing of magmatic fluids with cooler, more dilute meteoric waters.There is a systematic decrease in the measured and calculated isotopic compositions of hydrothermal waters with increasing paragenetic time and decreasing temperature: stage I, delta 18 O water = 8.0 to 1.5 per mil and delta D water = -56 to -74 per mil; stage II, delta 18 O water = 1.9 to -5.6 per mil and delta D water = -88 to -95 per mil; stage III, delta 18 O water = 0.9 to -3.0 per mil and delta D water = -93 to -97 per mil. The trend reflects the progressive increase of meteoric water involvement in the mineralizing system. During the cooling history of the Susan Granite stock, molybdenum and tungsten were partitioned preferentially into a coexisting magmatic hydrothermal fluid (delta 18 O = 8ppm, delta D = -56 to -72ppm). Sulfur isotope analyses of hydrothermal sulfide minerals suggest an igneous source of sulfur with a delta 34 S (sub Sigma S) value near 4 per mil. Following deposition of molybdenite and wolframite from magmatic fluids, wolframite was dissolved or replaced by scheelite in the outer and/or shallower portions of the hydrothermal system. This remobilization of tungsten and later redeposition as scheelite (at temperatures of 200 degrees -280 degrees C from fluids with delta 18 O = 1-2ppm) accompanied mixing with low-temperature meteoric fluids. Increasing involvement of progressively larger volumes of meteoric water resulted in successive deposition of base metal sulfides, fluorite, and carbonates.
TL;DR: It is believed that in the appropriate clinical situation, miliary tuberculosis may be suggested on HRCT, and in cases with no evidence of miliary nodules on the chest radiograph, HRCT scan may depict miliary nodsules in the lung parenchyma.
Abstract: Objective The purpose of this study was to define the range of abnormalities and to assess the contribution of high-resolution CT (HRCT) in the evaluation of miliary tuberculosis involving the lung parenchyma. Materials and methods The authors retrospectively reviewed HRCT scans of 11 patients with microbiologically or clinically proved miliary tuberculosis. Results In 10 patients, the most characteristic HRCT finding of miliary tuberculosis was the presence of small nodules uniformly distributed throughout both lungs. The profusion of nodules was numerous in all 10 patients. High-resolution CT scans showed both sharply and poorly defined, small nodules varying in sizes from 1 to 2 mm (n = 6), 1 to 3 mm (n = 2), and 1 to 4 mm (n = 2) in diameter. These nodules had a diffuse random distribution in the secondary lobule in all 10 patients. In 1 of the 10 patients with small nodules on HRCT, chest radiography had shown no evidence of miliary nodules in the lung. In addition to nodules, HRCT showed diffuse or localized reticular opacities superimposed on nodules in five patients, especially in the lower lung zones. In 1 of all 11 patients, ground-glass attenuation was the predominant abnormality seen on HRCT. Conclusion We believe that in the appropriate clinical situation, miliary tuberculosis may be suggested on HRCT. Moreover, in cases with no evidence of miliary nodules on the chest radiograph, HRCT scan may depict miliary nodules in the lung parenchyma.
TL;DR: In this paper, a glass-ceramics for low-firing temperature substrates was prepared by the addition of CeO2 flux to a glass of the MgO-Al2O3-SiO2 system.
Abstract: Dense glass-ceramics for low firing temperature substrates were prepared by the addition of CeO2 flux to a glass of the MgO-Al2O3-SiO2 system. The glass powders were fabricated by melting at 1500°C and ball milling. Glass powder compacts prepared by dry pressing were heated at 800–1000°C for 0.5–4 h and sintered at 900–1000°C for 3 h. The crystallization behaviour and sinterability of the glass powder compacts were analysed by thermal and thermomechanical techniques. X-ray diffractometry and scanning electron microscopy. The addition of CeO2 prevents the formation of μ-cordierite phase in the glass-ceramics and improves the formation of α-cordierite phase. The activation energy of the glass containing CeO2 for crystallization was lower than that of the CeO2-free glass. Therefore, crystallization properties were enhanced. Because the crystallization onset temperature increased and the softening temperature decreased on the addition of CeO2, the sinterability increased and dense glass-ceramics were fabricated below 1000°C. The properties of the glass-ceramics containing CeO2 appeared to be correct for low firing temperature substrates.
TL;DR: In this article, two quantum invariant operators are derived from the time-dependent Hamiltonian of the harmonic oscillator with an auxiliary condition, and the solution of the Schr\"odinger equation for the system, such as the eigenfunctions, eigenvalues, and minimum uncertainty, is derived by utilizing these invariants.
Abstract: The two quantum invariant operators are found from the time-dependent Hamiltonian of the harmonic oscillator with an auxiliary condition. The solution of the Schr\"odinger equation for the system, such as the eigenfunctions, eigenvalues, and minimum uncertainty, is derived by utilizing these invariant operators. The coherent states of this system are not the squeezed states, and the eigenfunction of the invariant operator is not the eigenfunction of the Hamiltonian of the system unless it is in the invariant representation. The squeezing function, which is an eigenfunction of the Hamiltonian of the system in the invariant representation and which also gives the minimum uncertainty, is obtained by a set of unitary transformed operators, i.e., squeezing operators.
TL;DR: In this paper, the electrical conduction characteristics of polyethylene with semiconductive electrodes have been investigated at electric fields of 10 to 600 kV/cm and at temperatures of 25 to 100/spl deg/C.
Abstract: The electrical conduction characteristics of polyethylene with semiconductive electrodes have been investigated at electric fields of 10 to 600 kV/cm and at temperatures of 25 to 100/spl deg/C. It was found that the conduction characteristics of the polyethylene were influenced not only by the constituents of the polyethylene but also the electrode materials. Space-charge-limited conduction was found to be the major conduction mechanism in all cases. Differences between conduction characteristics depending on the constituents of the XLPE are described and their causes are discussed. >
TL;DR: In this paper, an ancient field component structure is recovered from the red bed facies of the Upper Carboniferous-Lower Triassic Pyongan Supergroup by detailed thermal demagnetization.
Abstract: SUMMARY The Upper Carboniferous-Lower Triassic Pyongan Supergroup is exposed in an E-W trending syncline comprising the Samcheok Coalfield in eastern South Korea; it borders the southern margin of a NE-SW trending (Okcheon) zone of Upper Jurassic-Lower Cretaceous deformation (Daebo Orogeny). Although a Recent field overprint widely recorded in Korean rocks is represented here, an ancient field component structure is recovered from the red bed facies in this Supergroup by detailed thermal demagnetization. A prominent Upper Jurassic-Cretaceous overprint is widespread (DIZ = 56.1/54.8", agS = 9.6", palaeopole at 200.4"E, 46.7"N) and records the magnetic effect of the Daebo Orogeny within the Okcheon Belt. It is post-deformational in origin and appears to have been confined mainly to the Cretaceous Normal Superchron. It has been rotated clockwise since these times, in common with the main synclinal axis, as a consequence of dextral movements along the Tan Lu Fault System. Components predating this deformation are recovered from the Lower Triassic (DIZ = 1.1/19.4", agS = 18.2", palaeopole at 306.1°E, 63.2"N), Permian (DIZ = 358.3/11.5", c~~~ = 6.3", palaeopole at 311.9"E, 58.7"N) and Upper Carboniferous (DIZ = 34l.U-9.2", mgS = 7.2", palaeopole at 335.7"E, 44.6"N) sediments. Second-order small circle dispersions of site palaeopoles record unaccommodated tectonic rotations and are largest in the oldest beds below an Upper CarboniferousLower Permian unconformity. However, the presence of reversals, probably acquired before and after the Carboniferous-Permian Reversed Superchron, defines ancient field axes and identifies an Upper Carboniferous-Lower Triassic APW path. This path correlates with the contemporaneous path from the North China Block and is removed from the path from the South China Block; agreement with North China is enhanced when these results are corrected for the rotation indicated by the Cretaceous overprint. We therefore identify a first-order correlation between the Korean Peninsula and North China at least since Upper Palaeozoic times. Establishment of, and movements along, the Tan Lu Fault System since Mesozoic times have not obscured this palaeomagnetic correlation.
University of Colorado Boulder1, Fermilab2, University of Illinois at Urbana–Champaign3, Northwestern University4, University of Notre Dame5, University of Puerto Rico at Mayagüez6, University of California, Davis7, University of South Carolina8, Vanderbilt University9, University of North Carolina at Asheville10, University of Tennessee11, Korea University12
TL;DR: In this paper, a model consisting of a sum of Breit-Wigner amplitudes for the intermediate two-body resonant decay modes and a constant term for the nonresonant contribution is presented.