• Korean Journal of Construction Engineering and Management
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• v.20 no.6
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• pp.44-56
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• 2019

Recently, the paradigm of SOC investment has shifted from new construction to maintenance. This shift became more important for the highway system because it is as one of the most important SOC. In Korea, highway maintenance costs are about 20% of the total annual highway construction budget, which is about two-thirds of developed countries. In addition, establishing standardized guidelines for the highway maintenance operation is not in place. Therefore, in order for domestic road construction and maintenance technology to secure competitiveness in the global construction market, it is urgent to improve the management capacity for maintenance as well as the technology and management capacity. This study examines highway maintenance practices in OECD countries such as North America, Europe, Australia, New Zealand, and Japan to identify core elements of highway maintenance practice. It is imperative to establish a comprehensive management system based upon asset management principle. Even if the budget for the highway construction is reduced, investment in maintenance needs to be maintained.

• Publications of The Korean Astronomical Society
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• v.34 no.3
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• pp.31-40
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• 2019

We study the internal structure under the artificial mountain of Heumkyeonggak-nu, a Korean water-powered clock in the early Joseon dynasty. All the puppets on the artificial mountain are driven by the rotational force generated by the water wheel at their designated time. We design a model that work with three parts of the artificial mountain. At the upper part of the artificial mountain to the east, west, north and south, there are four puppets called the Four Mystical Animal Divinity and four ladies called the Jade Lady respectively. The former rotates a quarter every double hour and the latter rings the bell every hour. In the middle part of this mountain is the timekeeping platform with four puppets; the Timekeeping Official (Hour Jack), the Bell-, Drum-, and Gong-Warriors. The Hour Jack controls time with three warriors each hitting his own bell, drum, and gong, respectively. In the plain there are 12 Jade Lady puppets (the lower ladies) combined with 12 Oriental Animal Deity puppets. In his own time a lady doll pops out of the hole and her animal doll gets up. Two hours later, the animal deity lies down and his lady hides in the artificial plain. These puppets are regularly moved by the signal such as iron balls, bumps, levers, and so on. We can use balls and bumps to explain the concept of the Jujeon system. Iron balls were used to manipulate puppets of the timekeeping mechanism in Borugak-nu, another Korean water-powered clock in Joseon dynasty, which was developed earlier than Heumgyeonggak-nu. According to the North Korea's previous study (Choi, 1974), it is obvious that bumps were used in the internal structure of Heumgyeonggak-nu. In 1669, The armillary clock made by Song, I-young was also utilized bumps. Finally we presented mock-ups of three timekeeping systems.

• Journal of Korea Trade
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• v.25 no.8
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• pp.57-74
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• 2021

Purpose - This study aims to analyze the characteristics of network construction by Norwegian Air and AirAsia X, which are recognized as leading airlines in the long-haul LCC market. Based on this analysis, this study intends to provide implications for networking strategies for Korean LCCs that seek to enter the long-haul market when the aviation market stabilizes again upon the end of the COVID-19 pandemic. Design/methodology - To conduct the network analysis on long-haul low-cost airlines, the Official Airline Guide (OAG) Schedule Analyzer was used to extract long-haul data of Norwegian Air and AirAsia X. To analyze the trend of the long-haul route network, we obtained the data from 3 separate years between 2011 and 2019. The network was analyzed using UCINET 6.0 in order to examine the network structure of long-haul low-cost airlines and the growth trend of each stage. Findings - Analyzing the network of long-haul routes by visualizing the network structure of low-cost carriers showed the following results. In its early years, Norwegian Air's long-haul route network, centering on regional airports in Spain and Sweden, connected European regions, the Middle East, and Africa. As time passed, however, the network expanded and became steadily strong as the airline connected airports in other European countries to North America and Asia. In addition, in 2011, AirAsia X showed links to parts of Europe, such as London and Paris, the Middle East and India, and Australia and Northeast Asia, centering on the Kuala Lumpur Airport. Although the routes in Europe were suspended, the network continued to expand while concentrating on routes of less than approximately 7,000 km. It was found that instead of giving up on ultra-long-haul routes such as Europe, the network was further expanded in Northeast Asia, such as the routes in Korea and Japan centering on China. Originality/value - Until the COVID-19 pandemic broke out, Norwegian Air actively expanded long-haul routes, resulting in the number of long-haul routes quintupling since 2011. The unfortunate circumstance, wherein the world aviation market was rendered stagnant due to the outbreak of COVID-19, hit Norwegian Air harder than any other low-cost carriers. However, in the case of AirAsia X, it was found that it did not suffer as much damage as Norwegian Air because it initially withdrew from unprofitable routes over 7,000 km and grew by gradually increasing profitable destinations over shorter distances. When the COVID-19 pandemic ends and the aviation market stabilizes, low-cost carriers around the world, including Korea, that enter the long-haul route market will need to employ strategies to analyze the marketability of potential routes and to launch the routes that yield the highest profits without being bound by distance. For stable growth, it is necessary to take a conservative stance; first, by reviewing the business feasibility of the operating a small number of highly profitable routes, and second, by gradually expanding these routes.

• Journal of the Korean Geotechnical Society
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• v.22 no.12
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• pp.67-76
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• 2006

The reasonable assessment of the shear stiffness of a dredged soft ground and soft clay is difficult due to the soil disturbance. This study addresses the development and application of a new in-situ shear wave measuring apparatus (field velocity probe: FVP), which overcomes several of the limitations of conventional methods. Design concerns of this new apparatus include the disturbance of soils, cross-talking between transducers, electromagnetic coupling between cables, self acoustic insulation, the constant travel distance of S-wave, the rotation of the transducer, directly transmitted wave through a frame from transducer to transducer, and protection of the transducer and the cable. These concerns are effectively eliminated by continuous improvements through performing field and laboratory tests. The shear wave velocity of the FVP is simply calculated, without any inversion process, by using the travel distance and the first arrival time. The developed FVP Is tested in soil up to 30m in depth. The experimental results show that the FVP can produce every detailed shear wave velocity profiles in sand and clay layers. In addition, the shear wave velocity at the tested site correlates well with the cone tip resistance. This study suggests that the FVP may be an effective technique for measuring the shear wave velocity in the field to assess dynamic soil properties in soft ground.

• Journal of the Korea Institute of Information and Communication Engineering
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• v.10 no.7
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• pp.1180-1187
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• 2006

We Studied the method of structuring the sign system for pedestrians in the underground space by investigating and analyzing the sign system at Tae-jon Underground Commercial Area in Korea by 1) classifying the signs by types and comparing their numder for each type in sections, 2) classiflying the signs by the points of installation, types, functions and contents of information and comparing their numbers, 3) classifying the signs by their height and comparing by the points of installation, and 4) classifying the signs by their points of installation finding patterns. As a result, we found out that the current pedestrian signs in Tae-jon Underground Commercial Area could by classified into those installted with a certain regularity and those concentrated in at certain points. We also found out that there were many problems with the current signs system. The big gap of the type and numble of the signs, concentration of the signs at the gate (entrance), and the big gap of the function of the signs by their points of installation. And the gap of the signs by the number of installation is big between the North side and the South side. Most of signs concentrated in the South side show the problems of installation attached by the types and quantity of information. We suggest that type of information has consistency by posting of signs, at the same time, the necessary information should be offered in order for the pedestrians to easily recognize as they more in the Underground space.

• Journal of the Korean Wood Science and Technology
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• v.40 no.3
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• pp.186-193
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• 2012

The wood-concrete composite can be effectively applied for bridge superstructure, and the concept of fully composite action between each member is one of the most important consideration. Until now, related researches have been done mainly in North America and EU countries not enough to cover the fundamental studies. Therefore, this study is planned to perform one of the important issue for using the wood-concrete composite. The objective of this study is evaluation of shear performance with different anchorage length of steel rebar in wood. Prediction of the yield mode and the reference design value was firstly performed as the preliminary investigation. Then, initial stiffness, yield load and maximum load were derived from the shear test due to different anchorage length of the steel rebar (SD30A in Korean Standard) in wood. It was found out from this study that initial stiffness and yield load are not related with the anchorage length over 20 mm of anchorage length while maximum load shows increasing tendency till 60 mm of anchorage length. Pullout strength of inserted steel rebar in wood is considered to be one reason and this was also verified with the x-ray radiography.

• Journal of the Korean Geographical Society
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• v.40 no.5 s.110
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• pp.491-513
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• 2005

The Republic of Korea is planning to build the now Multi-functional Administrative city (NMAC). The purpose of this paper is to suggest the conceptual framework for this new city that relies on the Korean geomancy, oriental viewpoint on man and nature relationship, particularly in Korea. According to the Geomancy which could conceptualize the human-environment relationship in the site, the overall landscape image of the city could be symbolized by two flying crane with three Taegueks. In transforming the overall landscape image to urban form, two diamonds which means eternity and strength arises from the western spatial viewpoint, as means to protect and harmonize the human, land and mountain relationship in this site and the symbolic meaning of this site as generative and sacred place in Korean people's mind. On the one hand, through juxtaposing of the two diamonds a geometric structure shows up, on the other hand the main axis of the city could be established from two crane and three Taegueks. On the North-South axis from the core of the symbolic green axis, symbolic things will be located, and the administrative offices will be Placed on the East-West axis. Peripherals of the central axis also play a role in developing overall land use from image. The buildings and residents could be arranged and located according to undulations and this is based on the oriental theory of geomancy. We can build cultural amenities on the head part of the crane and on the core area.

• Journal of Navigation and Port Research
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• v.30 no.1 s.107
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• pp.97-104
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• 2006

Recently the first stage qf construction for Busan new port emerged over the sea surface at the north container terminal site. With this, there are lot of discussions and debates on increasing the water depth at the approaching channel and mooring basin from the existing 15m to 18m by dredging work in order to be able to serve 12,000TEU containership, and at the same time, correction to the reclamation plan of hinterland at the part of Undong Bay qf the new port site. Since the attack of typhoon 'Maemi' in 2003, it is expected that the design wave parameters for coastal and harbor structures in this area would be somewhat changed and so the extreme wave condition at each terminal and tranquility of berthing area does, and therefore, it is necessary to analyze the tranquility at each berth Hence in this study, we constructed a wave model for these conditions and performed simulation together with the circulation model simulation, compared with the field data collected The result showed the increase of the harbor response throughout the basin but not severe condition However, a certain location needs to be prepared for the rough sea condition when a severe typhoon hit the site.

• KSCE Journal of Civil and Environmental Engineering Research
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• v.36 no.5
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• pp.791-803
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• 2016

Recently, frequency of extreme rainfall events in South Korea has been substantially increased due to the enhanced climate variability. Korea is prone to flooding due to being surrounded by mountains, along with high rainfall intensity during a short period. In the past three decades, an increase in the frequency of heavy rainfall events has been observed due to enhanced climate variability and climate change. This study aimed to analyze extreme rainfalls informed by their frequency of occurrences using a long-term rainfall data. In this respect, we developed a Poisson-Generalized Pareto Distribution (Poisson-GPD) based rainfall frequency method which allows us to simultaneously explore changes in the amount and exceedance probability of the extreme rainfall events defined by different thresholds. Additionally, this study utilized a Bayesian approach to better estimate both parameters and their uncertainties. We also investigated the synoptic patterns associated with the extreme events considered in this study. The results showed that the Poisson-GPD based design rainfalls were rather larger than those of based on the Gumbel distribution. It seems that the Poisson-GPD model offers a more reasonable explanation in the context of flood safety issue, by explicitly considering the changes in the frequency. Also, this study confirmed that low and high pressure system in the East China Sea and the central North Pacific, respectively, plays crucial roles in the development of the extreme rainfall in South Korea.

• Journal of the Korean Home Economics Association
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• v.32 no.5
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• pp.165-182
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• 1994

Korea's clothing industry which has been country's leading export industry and basic strategical industry is now faced with many difficulties both domestically and internationally. Domestically it is faced with continuing shortage of manpower in both production line and management high labour cost causing increase in price putting more weight on behavior of consumers resulting in change of industrial environment and continuing structural problems of industry itself. Internationally it is faced with strengthening of import regulations and protectionism of developed countries and rapid emergence of underdeveloped countries as leading exporting nations. In reality export plays the most essential role in our economy and is especially sensitive to the external environmental factors. Already economic bloc phonomenon can be seen everywhere and is continuing to accelerate in place such as E. U in Europ, North & South America as NAFTA, and South East Asian contries which recent tendency of economic unity effort is present. These countries of such economic blocs are imposing heavy custom duties reinforcing provision of country origin and acting out strict inspection regulations in order to protect the interest of their own industry. Therefore it is vital to manufacture excellent quality goods For these reasons study in this area has brought attention in Korea as well as worldwide in the recent years. Apparel industry which requires professional technology and ability is the most competitive international business. In order to challenge the international market the high level of intelligence is most required to produce high quality goods. The purpose of this study is to analyze the relationship between functions and roles of marketing and to approach problems in more efficient manner. Apparel industry is composed of various programs such as design pattern making merchandising and textile science. To succeed in the business is to give the highest satisfaction to the targeted market. Hence this study will example the factors that determine the Cost Quality and Performance of apparel products. The study will involve following steps; firstly establish relationship between the quality concept and productivity of apparel products Secondly inquire in to marketing strategy laying stress on apparel production related factors focusing on merchandising marketing production and operations Thirdly prospect 21st century apparel industry focusing on garment production and trade and also other countries structural improvement Fourthly establish the new dimension of competitive factors by grasping the actual circumstance of Korea's apparel industry in the international market. The research method will include; First reality approach method by analysing the present state of industry Second literal analysis such as marketing comparisons between leading apparel exporting countries.