• International Journal of Highway Engineering
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• v.15 no.2
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• pp.105-112
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• 2013

PURPOSES : Compared to the criteria from advanced countries, Korea has conservative criteria for the buried depth of pipeline (about 30~70cm deeper) causing the waste of cost and time. Therefore, this research investigated the effect of various buried depths of pipeline on pavement performance in order to modify the criteria to be safe but economical. In addition, a recycled aggregate which is effective in economical and environmental aspect was evaluated to be used as a refilling material. METHODS : In this study, total 10 pilot sections which are composed with various combinations of pavement structure, buried depth of pipeline, and refilling material were constructed and the telecom cable was utilized as a buried pipeline. During construction, LFWD (Light Falling Weight Deflectometer) tests were conducted on each layer to measure the structural capacity of underlying layers. After the construction is completed, FWD (Falling Weight Deflectometer) tests and moving load tests were performed on top of the asphalt pavement surface. RESULTS : It was found from the LFWD and FWD test results that as the buried depth decrease, the deflections in subbase and surface layer were increased by 30% and 5~10%, respectively, but the deflection in base layer remained the same. In the moving load test, the longitudinal maximum strain was increased by 30% for 120mm of buried depth case and 5% for 100mm of buried depth case. Regarding the effect of refilling material, it was observed that the deflections in subbase and surface layer were 10% lager in recycled aggregate compared to the sand material. CONCLUSIONS : Based on the testing results, it was found that the change in buried depth and refiliing material would not significantly affect the pavement performance. However, it is noted that the final conclusion should be made based on an intensive structural analysis for the pavement under realistic conditions (i.e., repeated loading and environmental loading) along with the field test results.

• Korean journal of communication and information
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• v.63
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• pp.76-100
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• 2013

This work is for redefining of cultural diversity and suggesting measurement frame by casting light on changing cultural environment according to evolution of digital convergence media. So far, most of studies tend to confuse at using media diversity and cultural diversity and resultingly the concept of cultural diversity is not founded right yet. In communications field, there is a limit to measure cultural diversity which is substantive content because analysis of media diversity is mainly focused on financial measuring and quantitation. Therefore we define digital convergence media culture as metaculture here for analysis of cultural diversity. Additionally, we catagorize and analysis cultural diversity based on this metaculture into pluralism of media activity, diversity of cultural expression, diversity of cultural diffusion and diversity of cultural cognition. These measuration variables of the four categories are factors which can lighten aspects of cultural diversity in digital convergence media environment. Analysis of these factors of the four catagories will suggest a criterion to establish policies to protect cultural diversity. The policy of cultural diversity is to construct a cultural commune in envirnment of meta culture.

• Journal of the Korea Concrete Institute
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• v.23 no.3
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• pp.281-287
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• 2011

Recently, bridge construction technology has made great progress from development of high performance materials and new bridge types. However, most technology are based on methods of cast-in-place and material cost saving. The method of cast-in-place concrete causes environmental damages and costumer complaints. Especially, under bad weather conditions, the construction can not proceed. To overcome these disadvantages, new construction methods were developed to reduce construction time. These methods are called precast method. Most prefabricated methods have been applied to superstructure constructions of bridges, but very minutely applied to substructure constructions. The most important agendas on precast method are light weight and transportability of the precasted members, because very strict transporting specifications exist for road transportation of the precasted members. For example, the weight and length of coping members may be larger than the available transporting vehicles. Although column is constructed by precast method to save construction time, if coping member is constructed by cast-in-place method, then the column construction time reduction becomes meaningless. Therefore, in this study, a new precast coping member and a connecting system of column-coping member are proposed. The proposed method is verified by analyzing their ultimate performance through analysis and experimental study.

• Journal of Korean Academy of Nursing
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• v.29 no.1
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• pp.139-149
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• 1999

It is very important to establish precisely the historical phases of nursing. We nurses should try to acquire the central social position in the health management system in the near the future, the 21st Century. Therefore my treatise aims to orient the desirable phases of the history of nursing through the feministic survey of the history of nursing from the post medieval epoche to the modern epoche. During the time of the renaissance which gave morning light to the modern epoche, the antique Athenian thinking of sex was again revived. Athenian excluded the women from the public and autonomous regions. All the medical activity, once dominated by the women, was misfortunately regarded as superstition acted by witches. Accordingly, the nursing women were to hunted as witches. In short, in the early modern epoche, women began to be excluded from the history of medical activities. In the middle modern epoche characterized by the enlightenment movement and early capital economic system, capitalistic patriarchal system began to be formed by change in the economic system. The status of women began to be greatly dropped below by the social distinction of the private dimension of home and the Public dimension of job. The woman was deprived of even the occasion to get the official license of medicine and medical institutions were handed to the state or the powerful and rich merchants. Accordingly, nursing acted mainly in the nunnery as the total approach to the patients was destructed wholly and transformed into the means of earning the money. Therefore unprepared low class -women began to engage in nursing only for the money. From then on, nursing activity was tunneled through the dark age for 200 years. In the late modern epoche characterized by the contrast of the accumulated vast capital by industrialization and vast poverty of the peoples, feminism began to float over the surface for the acquisition of equality of men and women from England. A feminist, Nightingale insisted that the women as nurses should be responsible for the healthy life of man. She tried the professional nursing education for women. Accordingly she not only contributed to the intellectual progress of women but also inspired in women the consciousness of the professional job. She tried to realize the ideal of at-that-time-feminists by engaging in nursing all through life. She really paved the road to contemporary nursing. In the near the future, I will write to describe how the late modern epoche nursing has fallen into the dilemma through the 1st and 2nd world wars and matured capitalism and to consider contemporary nursing with the status of women. All these papers aim to give proper recognition of nursing and right orientation of the future 21st Century nursing.

• Journal of Radiation Protection and Research
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• v.41 no.3
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• pp.196-205
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• 2016

Background: The emergency planning zone (EPZ) of the city of Busan is divided into the precautionary actions zone (PAZ) and the urgent protective action planning zone; which have a 5-km radius and a 20-km to 21-km radius from the nuclear power plant site, respectively. In this study, we assumed that a severe accident occurred at Shin-Kori nuclear unit 3 and evaluated the dispersion speed of radiological material at each distance at various wind speeds, and estimated the effective dose equivalent and the evacuation time of PAZ residents with the goal of supporting off-site emergency action planning for the nuclear site. Materials and Methods: The total effective dose equivalent, which shows the effect of released radioactive materials on the residents, was evaluated using the RASCAL 4.2 program. In addition, a survey of 1,036 residents was performed using a standardized questionnaire, and the resident evacuation time according to road and distance was analyzed using the VISSIM 6.0 program. Results and Discussion: According to the results obtained using the VISSIM and RASCAL programs, it would take approximately 80 to 252.2 minutes for permanent residents to move out of the PAZ boundary, 40 to 197.2 minutes for students, 60 to 232.2 minutes for the infirm, such as elderly people and those in a nursing home or hospital, and 30 to 182.2 minutes for those temporarily within the area. Consequently, in the event of any delay in the evacuation, it is estimated that the residents would be exposed to up to $10mSv{\cdot}h^{-1}$ of radiation at the Exclusion Area Boundaries (EAB) boundary and $4-6mSv{\cdot}h^{-1}$ at the PAZ boundary. Conclusion: It was shown that the evacuation time for the residents is adequate in light of the time lapse from the initial moment of a severe accident to the radiation release. However, in order to minimize the evacuation time, it is necessary to maintain a system of close collaboration to avoid traffic congestion and spontaneous evacuation attempts.

• Journal of Korea Port Economic Association
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• v.33 no.2
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• pp.1-18
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• 2017

By using social network analysis, this study examined 102 countries, 281 ports, and 6,318 maritime routes associated with the global network of the Maersk Line. With the 'Belt and Road' in place, China is developing ports, expanding the cooperation with major ports, and increasing its influence on maritime transport. China's ports' reform and development implies establishing stable and independent logistic networks for supply of raw materials as well as exports and imports. This is closely related not only to individual ports' competitiveness, but also to relational structures between maritime powerhouses such as the US-which has the largest share and influence in the global market-and the surrounding countries. In this regard, an analysis of the maritime transport needs to consider the characteristics of individual ports together with those of each country. This study identified the characteristics of each port in light of the relationships in the global network of Maersk and applied them to each country. Moreover, the individual networks of China, the US, and Korea are compared. The findings showed that China, the US, Panama, Malaysia, and Spain accounted for large shares of the global network, while the shares of China, Korea, Taiwan, and Vietnam were high in China's network. In addition, by comparing individual networks of China, the US, and Korea, it emerged that Korean ports such as Busan and Gwangyang had secured a high level of competitiveness in the Chinese network.

• Korean Journal of Agricultural and Forest Meteorology
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• v.11 no.4
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• pp.143-150
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• 2009

Deicing salt is used to melt snow and ice on the road for traffic safety during the winter season, which accumulates in the roadside vegetation and induces visible injuries. The damage may accelerate particularly when it coincides with early spring leaf out. In order to better understand the response mechanisms, C. kousa (3-year-old) was irrigated twice prior to leaf bud in a rhizosphere with solutions of 0.5, 1.0, and 3.0% calcium chloride ($CaCl_2$) concentration, that were made by using an industrial $CaCl_2$ reagent practical deicing material in Seoul. Physiological traits of the mature leaves were progressively reduced by $CaCl_2$ treatment, resulting in reductions of total chlorophyll contents, chlorophyll a:b, photosynthetic rate, quantum yield, stomatal conductance, $F_V/F_M$, and NPQ. On the contrary, light compensation point and dark respiration were increased at high $CaCl_2$ concentration. A decrease in intercellular $CO_2$ concentration by stomatal closure first resulted in a reduced photosynthetic rate and then was accompanied by low substance metabolic rates and photochemical damage. Based on the reduction of physiological activities at all treatments ($CaCl_2$ 0.5%, 1.0%, and 3.0%), C. kousa was determined as one of the sensitive species to $CaCl_2$.

• Journal of the Korean Institute of Electrical and Electronic Material Engineers
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• v.34 no.6
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• pp.495-504
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• 2021

Energy Harvesting is a technology that can convert wasted energy such as vibration, heat, light, electromagnetic energy, etc. into usable electrical energy. Among them, vibration-based piezoelectric energy harvesting (PEH) has high energy conversion efficiency with a small volume; thus, it is expected to be used in various autonomous powering devices, such as implantable medical devices, wearable devices, and energy harvesting from road or automobiles. In this study, wasted vibration energy in an automobile is converted into electrical energy by high-power piezoelectric materials, and the generated electrical energy is found to be an auxiliary power source for the operation of wireless sensor nodes, LEDs, etc. inside an automobile. In order to properly install the PEH in an automobile, vibration characteristics includes frequency and amplitude at several positions in the automobile is monitored initially and the cantilever structured PEH was designed accordingly. The harvesting properties of fabricated PEH is characterized and installed into the engine part of the automobile, where the vibration amplitude is stable and strong. The feasibility of PEH is confirmed by operating electric components (LEDs) that can be used in practice.

• Journal of the Korean Association of Geographic Information Studies
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• v.21 no.4
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• pp.26-49
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• 2018

The purpose of this study was to verify the reliability of the solar radiation model and discuss its applicability to the urban area of Seoul for summer heat stress mitigation. We extended the study area closer to the city scale and enhanced the spatial resolution sufficiently to determine pedestrian-level urban radiance. The domain was a $4km^2$ residential area with high-rise building sites. Radiance modelling (SOLWEIG) was performed with LiDAR (Light Detection and Ranging)-based detailed geomorphological land cover shape. The radiance model was evaluated using surface energy balance (SEB) observations. The model showed the highest accuracy on a clear day in summer. When the mean radiation temperature (MRT) was simulated, the highest value was for a low-rise building area and road surface with a low shadow effect. On the other hand, for high-rise buildings and vegetated areas, the effect of shadows was large and showed a relatively low value of mean radiation temperature. The method proposed in this study exhibits high reliability for the management of heat stress in urban areas at pedestrian height. It is applicable for many urban micro-climate management functions related to natural and artificial urban settings; for example, when a new urban infrastructure is planned.

• KSCE Journal of Civil and Environmental Engineering Research
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• v.41 no.1
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• pp.85-91
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• 2021

In contrast to standard train tracks, tramlines are often set along public roads, with trams running among pedestrians and other vehicles. In some cities and towns, trams and buses share the same routes and stations. Under the current investment appraisal system, trams are classified into light rail when predicting traffic demand and calculating benefits, but in the case of non-capital areas, it is notable that the origin-destination and transit lines of buses are not provided in the Korea Transport Database distribution data. Due to this problem, it is difficult to reflect proper mode changing behaviors between route buses and trams. This study examines the impact on tramlines of bus routes that are not currently considered in non-capital areas. Following an analysis of the effect of tram projects according to whether bus routes are considered or not, an improvement in methodology is proposed. Through this study, it is expected that the investment appraisal system for the planning of new tramlines will be improved in the future.