• Ocean Systems Engineering
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• v.11 no.1
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• pp.83-97
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• 2021

The submerged U-shape breakwater interaction with the solitary wave is simulated by the Boussinesq equations using the finite-difference scheme. The wave reflection, transmission, and dissipation (RTD) coefficients are used to investigate the U-shape breakwater's performance for different crest width, Lc1, and indent breakwater height, du. The results show that the submerged breakwater performance for a set of U-shape breakwater with the same cross-section area is related to the length of submerged breakwater crest, Lc1, and the distance between the crests, Lc2 (or the height of du). The breakwater has the maximum performance when the crest length is larger, and at the same time, the distance between them increases. Changing the Lc1 and du of the U-shape breakwaters result in a significant change in the RTD coefficients. Comparison of the U-shape breakwater, having the best performance, with the averaged RTD values shows that the transmission coefficients, Kt, has a better performance of up to 4% in comparison to other breakwaters. Also, the reflection coefficients KR and the diffusion coefficients, Kd shows a better performance of about 30% and 55% on average, respectively. However, the model governing equations are non-dissipative. The non-energy conserving of the transmission and reflection coefficients due to wave and breakwater interaction results in dissipation type contribution. The U-shape breakwater with the best performance is compared with the rectangular breakwater with the same cross-section area to investigate the economic advantages of the U-shape breakwater. The transmission coefficients, Kt, of the U-shape breakwater shows a better performance of 5% higher than the rectangular one. The reflection coefficient, KR, is 60% lower for U-shape in comparison to rectangular one; however, the diffusion coefficients, Kd, of U-shape breakwater is 35% higher than the rectangular breakwater. Therefore, we could say that the U-shape breakwater has a better performance than the rectangular one.

• KSCE Journal of Civil and Environmental Engineering Research
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• v.13 no.5
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• pp.1-11
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• 1993

Precast/Prestressed concrete segmental bridges with moderate range of span length normally have a constant section height for economic segment manufacturing. Inside sectional dimension is often controlled for design of non-prismatic section between supports when variable stiffness is required. It is usual, in the preliminary design stage, to adopt trial bridge sections by past experience or by approximately estimated member forces. Three bridge models of different member stiffness have been selected to investigate flexural stiffness effects on member forces for preliminary design stage. The selected bridge stiffness has been determined by the flexibility index from review of the practically usable sections.

• Journal of Korean Society of Transportation
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• v.12 no.4
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• pp.53-63
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• 1994

도시확산과 지방분권화의 시대적 추세는 도시경제 및 교통-토지이용모형의 구조에 도 영향을 미치고 있다. 첫째, 도시의 공간적 확산과 고밀도화로 인한 도시내 제반 경제.사 회활동이 이전보다는 훨씬 다양해지고 복잡해지고 있다. 둘째, 지방분권화로 인해 대도시내 작은 지역단위별 주민들이 자신의 지역문제에 대한 관심과 요구들이 증가하고 있다. 또한 대부분의 도시계획 및 정책은 대도시내 공간적으로 뿐만 아니라 서로 다른 이익집단에 상이 한 영향을 미치는 것으로 파악되고 있다. 이러한 요인으로 인해 대도시 모형은 1) 도시내 제반활동의 흐름을 체계적으로 분석할 수 있어야 하며, 2) 도시계획 및 정책의 효과를 도시 내 세분화된 공간별, 업종별로 분석할 수 있어야 한다. 본 연구는 Wilson의 모형에 도시내 중요한 경제활동인 통근과 shopping변수를 추가하여 Wilson의 모형이 대도시모형으로 이용 될 때 발생하는 문제를 해결하였다. 또한 모형을 구성함에 있어 Matrix Inversion과 Non-linear Programming Model의 두 가지 방법을 도입하고 그 장단점을 비교하였다. Matrix Inversion의 경우 해 (Solution)을 찾기가 쉬워 실질적이고 승수계산과정에서 각 Round마다 승수의 크기를 알 수 있는 반면 Programming을 통한 모형의 경우 제약식의 도 입이 용이하고 목적함수의 형태를 바꾸는 것이 가능하므로 이론적 기틀을 세우는데 유리한 접근방법으로 분석되었다.

• KDI Journal of Economic Policy
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• v.46 no.1
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• pp.53-89
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• 2024

The effects of the betterment of enforced intellectual property rights (IPRs) provisions on services export diversification are investigated. The analysis used an unbalanced panel dataset of 76 developing countries over the period of 1970-2014. The empirical analysis is based on the feasible generalized least squares estimator. It suggests that the implementation of weaker IPR protection fosters services export diversification in less developed countries (i.e., those whose real per capita incomes are less than US$US$ 1458.60), including those with a low level of export product upgrading. Conversely, in relatively advanced developing countries (countries whose real per capita income exceeds US$ 3356.80), including those with high levels of export product upgrading, the implementation of stronger IPR laws induces greater services export diversification. Finally, the analysis revealed the existence of a non-linear relationship between IPR protection and services export diversification. The implementation of stronger intellectual property laws spurs services export diversification in countries with high degree of IPR protection, especially when IPR protection exceeds a certain level, recorded here as having a score of 1.197. In contrast, in countries with weaker IPR protection, in particular those with IPR protection levels that score less than 0.915, it is rather the implementation of weaker intellectual property laws that promotes services export diversification.

• Economic and Environmental Geology
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• v.46 no.2
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• pp.165-178
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• 2013

This study is for the genetic differences of two closed asbestos mines from Jeongjeon and Ocheon areas in Boryoung, Chungnam. They are mined asbestos for past several decades. Host rocks are serpentinites for Jeongjeon mine and dolomites for Ocheon mine. Asbestos samples and their host rocks are collected from the field trips and examined with microscopes and FESEM, and analysed with XRD and EDX to confirm for the type and/or compositions of the minerals. The asbestos occur as layers, cracks and fractures assummed as a pathway of the hydrothermal water, but show different characteristics. The serpentinites from the Jeongjeon mine contain chrysotile, tremolite and actinolite asbestos. Non-asbestos minerals including tremolite and actinolite were also found. The chrysotiles occur as a cross fiber or slip fiber at veins and along cracks of several mm to cm thickness. Tremolite and actinolite asbestos occur along cracks and fractures of several cm to ten cm thickness. It suggests that the asbestos from Jeongjeon area were formed by the reactions between serpentinite and hydrothermal water. The dolomites of the Ocheon mine only contain tremolite and actinolite asbestos. The asbestos occur along layers, cracks and fractures, suggestive of asbestos from Ocheon area formed by the reactions between dolomite and hydrothermal waters influxed along layers, cracks and fractures. Overall results suggest that two asbestos mines showing different host rocks are located in a Boryoung area. They show a different type of asbestos minerals, reflecting variety of petrogeneses.

• Asian-Australasian Journal of Animal Sciences
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• v.14 no.8
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• pp.1118-1124
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• 2001

Fifteen lactating crossbred cows were randomly allotted to three groups of 5 each, and fed three isoproteinous concentrate mixture varying in RDP and UDP ratios, viz. 71: 29 (T1) and 58: 42 (T2) and 44: 56 (T3), along with green maize and wheat straw given as 2/3 and 1/3 of total roughage respectively, for a period of 120 days. The DM intake (kg/d) differed significantly (p<0.01) among the treatments as well as among the fortnights over a period of 120 days. DMI (kg/d) progressively increased from first to eighth fortnight in all the treatments. The daily DMI (% BW) was significantly (p<0.01) lower in T1 (2.37) than those of T2 (2.82) and T3 (2.67). The body weights of cows decreased up to 4th fortnight in T1 and up to 3rd fortnight in T2 and T3, then it showed an increasing trend till the end of the experiment in all the treatments. Cows in T1 lost 10 kg body weight but cows in T2 and T3 gained 23 and 12 kg the body weight, respectively. Both the milk and FCM yield differed significantly (p<0.01) among the fortnights. The FCM yield increased up to 2nd fortnight in all the treatments and thereafter, the FCM yield declined gradually as the lactation advanced. The FCM yield (kg/d) was significantly (p<0.05) higher in T3 (10.47) than in T2 (9.81) and T1 (9.68), however, milk yield, SCM yield and milk energy yield did not differ among the treatments as well as among the fortnights. Fat and protein % in milk increased as the lactation advanced. However, fortnightly SNF % in milk showed an irregular trend. The % fat, protein, SNF and total solids in milk differed significantly (p<0.01) among the fortnights. The % fat and protein in milk varied significantly (p<0.01) among the treatments, being lowest in T1 and highest in T3. The feed efficiency for milk production showed a non-significant variation among the treatments as well as among the fortnights, but increased with the increase in UDP level. It is concluded that by increasing the UDP level from 29 to 56 per cent of CP in the diet of medium producing cows, the milk production increases and cost of milk production reduces.

• Economic and Environmental Geology
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• v.37 no.6 s.169
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• pp.603-612
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• 2004

Pyrochlore is known as one of the most promising materials for the immobilization of radionuclide in high level waste. This study included the synthesis, phase relation and characteristics of $pyrochlore(CaCeZr_xTi_{2-x}O_{7,\;x=0.2\~2.0)$ in the system of Ca-Ce-Zr-Ti-O. Using the CPS(Cold pressing and sintering) method, the mixtures of $CaCO3_,\;CeO_2,\;ZrO_2\;and\;TiO_2$ oxides were pressed, and sintered at $1100\~1600^{\circ}C$ for 20 hours. The optimal synthetic conditions at various compositions were differed from 1300 to $1600^{\circ}C$ Even in the optimal temperatures, pyrochlore or fluorite coexisted with minor amount of perovskite, $CeO_2\;or\;Ce_{0.75}Zr_{0.25}O_2$. It was confirmed that pyrochlore and fluorite structures were stable at $x\leq0.6\;and\;x\geq1.0$, respectively. Especially, the compositions of pyrochlore or fluorite showed non-stoichiometric compositions in that contents of Ca and Ti were more deficient and those of Zr and Ce were more excess than batch compositions with the increase of x value. These characteristics stemmed from the behavior of elements occupied at eight- and six-coordinated site, and then caused the coexistence of perovskite, $CeO_2\;or\;Ce_{0.75}Zr_{0.25}O_2$ along with pyrochlore or fluorite.

• Economic and Environmental Geology
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• v.32 no.4
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• pp.385-398
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• 1999

The Narim gold mine is located approimately 200km southeast of Seoul within the Muju mineralized district of the Sobaegsan gneiss complex, Korea. Environmental geochemistry were undertaken for various kinds of water (surface, ground and mine water) collected of April, September and November in 1998 from the narim mine creek. Hydrogeochemical compositions of water samples are characterized by the relatively significant enrichment of Na+K, alkali ions, $HCO_{3}$, $NO_{3}$, Cl and F in groundwater, wheras the mine and surface waters are relatively enriched in Ca+Mg, hea표 metals and $SO_{4}$. Therefore, the groundwaters belong to the (Na+Ca)-( $HCO_{3}+SO_{4}$) type, respectively. The pH and EC values of the non-mining creek surfers are relatively lower compared with those of the surface water of the mine and ore dump area. The d values ($\delta$D-8$\delta^{18}$O) of all kinds of water from the Narim mine creek are 5.8 to 13.1 The range of $\delta$D and $\delta^{18}$O values (relative to SMOW) are shown in distinct two groups as follows: for the April waters of -64.8 to -67.8$\textperthousand$ and -9.6 to -10.0$\textperthousand$(d value=10.1 to 13.1), and for the November waters of -65.9 to -70.2$\textperthousand$ and -9.3 to -9.6$\textperthousand$ (d value=5.8 to 7.9), respectively. This range variation indicates that two group water were composed of distinct waters with seasonal difference. Geochemical modeling showed that mostly toxic metals (As, Fe, Mn, Ni, Pb, Zn) may exist largery in the from of metal $(M2^+)$ and metal-sulfate $(MSO_4\;^{2-$\mid$),\; and \;SO_4^{2-$\mid$}$ concentration influenced the speciation of heavy metals in the meteoric water. These metals in the groundwater could be formed of $CO_3 \;and \;(OH)_3$ complex ions. Using computer program, saturation index of albite, calcite, dolomite in meteoric water show undersaturated and progreddively evolved toward the saturation state, however, ground and mine water are nearly saturated. The gibbsited water-mineral reaction and stabilities suggest that the weathering of silicate minerals may be stable kaolinite, illite and Nasmectite. The clay minerals will be transformed to more stable kaolinite owing to the contiunous reaction.

• English & American cultural studies
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• v.10 no.2
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• pp.73-97
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• 2010

Representation of destitution may be considered as an expression of a social desire toward forging a bond or solidarity with the impoverished. However, political and ethical demands of the solidarity force the formulaic framework structuring the form of representation to its limits. The thesis aims to examine the responses to such demands within the tradition of modernist literature that can be traced from Charles Baudelaire, Knut Hamsun to Franz Kafka and that somehow culminates with Samuel Beckett, and to analyze how the issue of destitution that weaves through Beckett's works criticizes and inherits such a heritage. Whereas destitution in 19th century Realism is structurally fixed and its potential for change is inherently excluded, for these writers, destitution is no longer the state of rigid reality in which any possibility is limited. It is destitution as an imperative that calls for exploitation of possibilities that can be recuperated from the impoverished condition of destitution. What these writers consistently resist against is destitution that leads to compensation and reward. Since occupying a superior position toward the other as the subject of description or sympathy can be seen as one form of profit or reward, they have persistently pursued absolute solitariness and austere conditions rather than prematurely simulating a sense of solidarity and community. The ultimate goal of destitution as an imperative is to pursue destitution in order to worsen it by identifying and then excluding and expending possessions and assets to a state of penury. This is a paradoxical process that opens up the realm of possibilities of destitution and redefines it as abundance and wealth. Destitution for Beckett as seen in the writers above is the objective of literature. But, what he focuses on is to amplify the shreds of economic world that still remain in a state of poverty and to reveal extreme poverty as a state of odd affluence and to transform it into a pursuit of accumulation and profit. One of his famous axioms, "less is more", contains the essence of such a paradoxical strategy. In a sense, such approach is a twist on the strategy that identifies and uses any remaining potential hidden in destitution as was pursued by other writers. It also expands on the imagination of the destitute described by Hamsun. But Hamsun and Beckett are diametrical opposites. Unlike Hamsun, Beckett does not link imagination with a sense of guilt. Imagination is not intended to overcome the destitute reality nor to culminate in artistic martyrdom as in the case of Kafka's hunger artist. The imagination of the impoverished in Beckett is simply a hilarious game and not an escape that ends in a sense of guilt. This game formulates a "rhetorical question" or derision at the ironical situation where the pursuit of hunger and art as the disinterestedness has been turned into symbolic capital. It is inherently a fundamental critique at the aestheticization of destitution that has been pursued by Modernism. Beckett's efforts at divulging falsehood inherent in non-profit acts such as charity, donation and hospitality are dissections of social fictions in which aestheticization of destitution remains a part of the whole.

• Journal of the Korean Geotechnical Society
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• v.21 no.9
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• pp.35-44
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• 2005

Recently, underground cavities such as limestone cavity and abandoned mine give rise to a lot of damage in SOC facilities. But there are many difficult problems such as delay of the working terms and enormous economic losses in finding a new method and changing construction design. In this study, a new filling material for underground cavities was developed using the stone-dust classified as industry waste polluting environment. As a result of test, filling material properties was that a compressive strength was $34{\~}60\;kgf/cm^2$, a change ratio in length was $0.268{\~}0.776\%$ and water absorption was $34.3{\~}46.9\%$. Also as a result of suspended mass test and pH test, it was confirmed that the developed filling material has a characteristic of non-separating in water and it was an environmentally friendly material.