• Journal of the Korean GEO-environmental Society
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• v.12 no.1
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• pp.61-70
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• 2011

The impact protection system consists of an arrangement of circular sheet pile cofferdams-denoted dolphin structuredeeply embedded in the seabed, filled with crushed rock and closed at the top with a robust concrete cap. Centrifuge model tests were performed to investigation the behaviors of dolphins in this study. Total 7 quasi-model tests and 11 dynamic model tests were performed. The main experimental results can be summarized as follows. Firstly, The experimental force-displacement results for quasi-static tests show a limited influence on the initial stiffness of the structure from the change in fill density and the related change in the stiffness of the fill. And by comparing the dissipation at the same dolphin displacement it was found that the denser fill increase the dissipation by 16% for the 20m dolphin and by 23% for the 30m dolphin. The larger sensitivity for the large dolphin is explained by a larger contribution to the dissipation from strain in the fill. In low level impacts the dynamic force-response is up to 26~58% larger than the quasi-static and the dissipation response is showed larger in small displacement. Hence, it is concluded conservative to use the quasi-static response characteristics in the approximation of the response, and it is further concluded that the dolphin resistance to low level impacts is demonstrated to be equivalent and even superior to the high level impacts.

• Journal of the Korean GEO-environmental Society
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• v.12 no.7
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• pp.23-29
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• 2011

The oxidation slag has been widely used in civil engineering project, whereas the reduced slag from electric furnace has yet to be applied. Consequently in order to find out the recycling method in civil engineering field, the mineral compositions of the reduced slag were analyzed and some tests on water quality were performed to estimate the potential release of toxic compounds. Slag-soil mixtures of 0, 10, 20 and 30%(dry weight) soil were prepared in lysimeter columns and the effluents were collected with the period of one, two and four week options in closed system, respectively. The result from qualitative and quantitative analysis using X-ray Diffraction(XRD) and X-ray Fluorescence(XRF) indicates that the main mineral of the reduced slag is $Ca_2(SiO_4)$, a kind of calcium silicate. Also, the leaching medium analyzed by Inductively Coupled Plasma Optical Emission Spectroscopy(ICP-OES) showed that main heavy metals such as Al, Fe and Mn are included in the reduced slag due to the effect of steel production process. It can be seen that the leachate does not violate the regulation guide line of waste material of heavy metal. Also the pH levels were increased from pH 6.9 for 0% soil to pH 10 for 30% soil. However the influence on leachate circulation period of one through four weeks was negligible.

• Journal of Korean Society of Forest Science
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• v.100 no.3
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• pp.466-475
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• 2011

This study purposed to analyze the spatial pattern and the amount of carbon emission at the deforestation area based on the administrative and GIS data. The total size of deforestation area in last nine years (2000-2008) was about 649 ha, and it was occurred annually about 72 ha. The occurrence rate of deforestation per administrative area in Wonju was about 0.74%. It was 0.34% higher than that of Kwangwondo, and 0.06% less than that of National rate. On the other hand, the forms of deforestation by purpose were not related to the administrative district unit. The number of deforestation forms was highest at settlements. second most frequent form is other land. Grassland showed the lowest score. In addition, the deforestations were more occurred which is closed to the existing housing and building rather than roads. The number of deforestation was 1.2 times higher based on 300m. Seventy percent of deforestation was occurred which is less than 0.5 ha in size, and it increased to 91% when the size is less than 1ha. The total size of theoretical carbon emission based on deforestation area was estimated at 23,424 tc, and average annual carbon emission was estimated by 2,603 tc. Carbon emission per ha was 36.1 tC/ha. This study results will be useful to construct the greenhouse gas statistical verification system against the Post-2012 by GIS.

• Journal of the Korean Society of Surveying, Geodesy, Photogrammetry and Cartography
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• v.39 no.2
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• pp.93-101
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• 2021

Recently, with the urban redevelopment and the spread of the planned cities, there is increasing interest in the wind environment, which is related not only to design of buildings and landscaping but also to the comfortability of pedestrians. Numerical analysis for wind environment prediction is underway in many fields, such as dense areas of high-rise building or composition of the apartment complexes, a precisive 3D building model is essentially required in this process. Many studies conducted for wind environment analysis have typically used the method of creating a 3D model by utilizing the building layer included in the GIS (Geographic Information System) data. These data can easily and quickly observe the flow of atmosphere in a wide urban environment, but cannot be suitable for observing precisive flow of atmosphere, and in particular, the effect of a complicated structure of a single building on the flow of atmosphere cannot be calculated. Recently, drone photogrammetry has shown the advantage of being able to automatically perform building modeling based on a large number of images. In this study, we applied photogrammetry technology using a drone to evaluate the flow of atmosphere around two buildings located close to each other. Two 3D models were made into an automatic modeling technique and manual modeling technique. Auto-modeling technique is using an automatically generates a point cloud through photogrammetry and generating models through interpolation, and manual-modeling technique is a manually operated technique that individually generates 3D models based on point clouds. And then the flow of atmosphere for the two models was compared and analyzed. As a result, the wind environment of the two models showed a clear difference, and the model created by auto-modeling showed faster flow of atmosphere than the model created by manual modeling. Also in the case of the 3D mesh generated by auto-modeling showed the limitation of not proceeding an accurate analysis because the precise 3D shape was not reproduced in the closed area such as the porch of the building or the bridge between buildings.

• Journal of Bio-Environment Control
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• v.32 no.1
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• pp.34-39
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• 2023

Growth modeling in plant factories can not only control stable production and yield, but also control environmental conditions by considering the relationship between environmental factors and plant growth rate. In this study, using the expolinear function, we modeled perilla [Perilla frutescens (L.) Britt.] cultivated in a plant factory. Perilla growth was investigated 12 times until flower bud differentiation occurred after planting under light intensity, photoperiod, and the ratio of mixed light conditions of 130 μmol·m^-2·s^-1, 12/12 h, red:green:blue (7:1:2), respectively. Additionally, modeling was performed to predict dry and fresh weights using the expolinear function. Fresh and dry weights were strongly positively correlated (r = 0.996). Except for dry weight, fresh weight showed a high positive correlation with leaf area, followed by plant height, number of leaves, number of nodes, leaf length, and leaf width. When the number of days after transplanting, leaf area, and plant height were used as independent variables for growth prediction, leaf area was found to be an appropriate independent variable for growth prediction. However, additional destructive or non-destructive methods for predicting growth should be considered. In this study, we created a growth model formula to predict perilla growth in plant factories.

• Journal of Intelligence and Information Systems
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• v.29 no.4
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• pp.51-68
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• 2023

With the emergence of the internet and the increasing use of online communities for over 20 years, the age range of users has also been rising. This study explores the linguistic changes that have occurred as the user age in online communities has increased. To do this, data was collected and analyzed from an online community that has been actively operating, despite new member registrations being closed nine years ago. By comparing the posts over an 11-year period from 2012 to 2022, changes such as an increase in average comments, a decrease in interrogative sentences, and a decrease in imperative statements were observed. The study also proposed loneliness due to aging and a decline in curiosity and confidence as potential causes of these changes. In South Korea, which is rapidly entering an aging society unprecedentedly fast on a global scale, the increase in single-person households has evolved loneliness from a personal issue to a social problem, manifested in an increase in solitary deaths and reclusive individuals. This research sheds light on one aspect of these social phenomena through the analysis of data from a large online community.

• Journal of Internet Computing and Services
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• v.25 no.1
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• pp.189-198
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• 2024

AI is accepted not only in the private sector but also in the defense sector as a cutting-edge technology that must be introduced for the development of national defense. In particular, artificial intelligence has been selected as a key task in defense science and technology innovation, and the importance of data is increasing. As the national defense department shifts from a closed data policy to data sharing and activation, efforts are being made to secure high-quality data necessary for the development of national defense. In particular, we are promoting a review of the business budget system to secure data so that related procedures can be improved to reflect the unique characteristics of AI and big data, and research and development can begin with sufficient large quantities and high-quality data. However, there is a need to establish standardization and quality standards for structured data and unstructured data at the national defense level, but the defense department is still proposing standardization and quality standards for structured data, so this needs to be supplemented. In this paper, we propose an unstructured data set standard format for defense unstructured data sets, which are most needed in defense artificial intelligence, and based on this, we propose a standardization method for defense unstructured data sets.

• Korean Journal of Radiology
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• v.24 no.7
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• pp.647-659
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• 2023

Objective: The study was conducted to investigate the effect of correct occlusion of the left atrial appendage (LAA) on intracardiac blood flow and thrombus formation in patients with atrial fibrillation (AF) using four-dimensional (4D) flow magnetic resonance imaging (MRI) and three-dimensional (3D)-printed phantoms. Materials and Methods: Three life-sized 3D-printed left atrium (LA) phantoms, including a pre-occlusion (i.e., before the occlusion procedure) model and correctly and incorrectly occluded post-procedural models, were constructed based on cardiac computed tomography images from an 86-year-old male with long-standing persistent AF. A custom-made closed-loop flow circuit was set up, and pulsatile simulated pulmonary venous flow was delivered by a pump. 4D flow MRI was performed using a 3T scanner, and the images were analyzed using MATLAB-based software (R2020b; Mathworks). Flow metrics associated with blood stasis and thrombogenicity, such as the volume of stasis defined by the velocity threshold ($\left|\vec{V}\right|$ < 3 cm/s), surface-and-time-averaged wall shear stress (WSS), and endothelial cell activation potential (ECAP), were analyzed and compared among the three LA phantom models. Results: Different spatial distributions, orientations, and magnitudes of LA flow were directly visualized within the three LA phantoms using 4D flow MRI. The time-averaged volume and its ratio to the corresponding entire volume of LA flow stasis were consistently reduced in the correctly occluded model (70.82 mL and 39.0%, respectively), followed by the incorrectly occluded (73.17 mL and 39.0%, respectively) and pre-occlusion (79.11 mL and 39.7%, respectively) models. The surfaceand-time-averaged WSS and ECAP were also lowest in the correctly occluded model (0.048 Pa and 4.004 Pa^-1, respectively), followed by the incorrectly occluded (0.059 Pa and 4.792 Pa^-1, respectively) and pre-occlusion (0.072 Pa and 5.861 Pa^-1, respectively) models. Conclusion: These findings suggest that a correctly occluded LAA leads to the greatest reduction in LA flow stasis and thrombogenicity, presenting a tentative procedural goal to maximize clinical benefits in patients with AF.

• Journal of Korea Technology Innovation Society
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• v.16 no.1
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• pp.323-345
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• 2013

In this paper, problems with the Korean system regulating the use of university royalties are identified and investigated in order to suggest measures to improve the system in a way that provides a better R&D environment at universities. The Delphi technique was used to gather data from royalty specialists at universities and government ministries. The first Delphi survey conducted used open questions to identify problems in the use of university royalties. Then, closed questions were used for the second Delphi survey. The number of responses and the frequency of answers were analyzed after the first survey, and validity, stability, and reliability analyses were conducted for the second survey. The measures suggested to improve the system regulating the use of university royalties are as follows: First, bonuses for researchers, which are currently 50% or more of collected royalties, need to be decreased, as they are rather high compared to similar bonuses in developed countries, which are around 30% of collected royalties. The guideline for limiting the bonuses, which is explained as XX% or less of collected royalties, is suggested to prevent the excessive use of royalties. Second, rewards for those who contribute to technology transfer and commercialization should be increased. It is also important to build a consensus around the need to reward those who contribute to technology transfer and commercialization. Third, the scale of re-investment into R&D needs to increase. Regulations on royalties should be meaningfully applied to create a positive feedback structure for R&D, which can be described as the process of research, R&D outcomes, technology transfer, collecting royalties, rewarding researchers, and re-investing in R&D. To build a university's R&D capability, re-investment into R&D needs to be regularized as XX% or more of royalties. Fourth, regulations on the royalties of ministries and universities need to be unified. Each category for using royalties needs to be regularized, with detailed matters such as the guideline, process and method for using royalties specified. Also, universities need to make their own specific regulations. Fifth, specific priorities on the use of royalties need to be suggested. Regulation is necessary for the categories that do not have guideline and priorities for the use of royalties. It is hoped that the findings of this research will contribute to reinforcing the R&D capability of universities.

• The Korean Nurse
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• v.35 no.2
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• pp.71-91
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• 1996

The objectives of thes study were to identify the need for equipment development in nursing, and to determine the priorities for that development. The study was descriptive study done between March 2 and May 30, 1995, in which the subjects, including 421 patients, 223 family members, and 198 nurses from neurosurgery, orthopedic, rehabilitation medicine, internal medicine and intensive care units of nine general hospitals in Seoul, completed a questionnarie developed by the research team. The questionnaire consisted of 35 open and closed questions. Data was analyzed using frequencies and percentages. The results ware summarized as follows: 1) The average age of the nurses was 27.9 years, 48% of the patients were between 20 and 40 years of age, and 17% were over 60. The average lingth of experience for the nurse subjects was four years five months with 36.9%. having over five years experience. The most frequent diagnoses of patients were spinal disc(35.9%), internal medicine disease(26.0%), cerebral vascular accident(16.6%) and spinal cord injury(10%) 2) Many of the nurses(96.4%) reported deficiencies with existing equipment and 96.5% of the nurses, but only 79.8% of the patients, nurses' time. Further, 82.3% of the nurses and 75.8% of the patients felt that the development of new equipment would lead to a decrease in the cost of nursing care. 3) Nurses felt that the greatest areas of inconvenience were patient feeding(71.7%), hygiene(71.2%), caring for a patient confined to bed(70.7%), patient clothing(67.2%), mobility transfers(63.5%) and urinary elimination(52.0%). However, patients and family members listed the following as being the most inconvenient: urinary elimination(58.7%), Hygiene(50.5), feeding(48.4%), mobility transfers(47.1%) and bed care(45.2%). 4) Generally the nurses listed more inconveniences and patients and family members listed more demands for the development of equipment. These included utensils with large handles, and regulators for tube feedings; mattresses that provide for automatic position change and massage, which have patient controlled levers and a place for bed pan insertion; automatic lifts or transfer from bed to wheelchair; equipment to facilitate washing and oral hygiene as well as equipment that will allow patients with spinal cord injuries easy access to showers; a bed pan/urinal for women that is comfortable and effective from which urine can be measured and disposed of easily; disposable dressing sets and tracheostomy care sets and a convenient way of measuring changes in wound size; a safe delivery system for oxygen, a variety of mask sizes and better control of humidity, tracheal material than at present, as well as a communication system for patients with tracheostomies; clothing that will allow access to various parts of the body for treament or assessment without patients having to remove all of their clothing; and finally a system that will allow the patient to control lighting, telephones and pagers. Priority areas for equipment development reported by the nurses were, urinary elimination(58. 7%), hygiene(50.5%), feeding(48.4%), mobility transfers(47..1%), bowel elimination(40.8%). Those reported by the patients family members were feeding(71.7%), hygiene(70.0%), bedcare(70.7%), clothing(67.2%), mobility transfers(63.6%), urinary elimination(52.9%) and bowel elimination(50.5%) Altogether, nurses, patients and family members listed the following as priorities; clothing (178), bed care(144), urinary elimination(92), environment(81), hygiene(70). Further, a health professional forum listed urinary elimination, oxygen delivery, medication delivery, mobility transfers, bed care and hygiene in that order as priority areas. From this study it can be concluded that the first need is to develop equipment that will address the problems of urinary elimination. To do (l)This nurses who are interested in equipment development should organize an equipment development team to provide a forum for discussion and production of equipment for nursing.