• Journal of Korean Society of Transportation
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• v.22 no.3 s.74
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• pp.145-157
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• 2004

The cycle length design model of the Korean traffic responsive signal control systems is devised to vary a cycle length as a response to changes in traffic demand in real time by utilizing parameters specified by a system operator and such field information as degrees of saturation of through phases. Since no explicit guideline is provided to a system operator, the system tends to include ambiguity in terms of the system optimization. In addition, the cycle lengths produced by the existing model have yet been verified if they are comparable to the ones minimizing delay. This paper presents the studies conducted (1) to find shortcomings embedded in the existing model by comparing the cycle lengths produced by the model against the ones minimizing delay and (2) to propose a new direction to design a cycle length minimizing delay and excluding such operator oriented parameters. It was found from the study that the cycle lengths from the existing model fail to minimize delay and promote intersection operational conditions to be unsatisfied when traffic volume is low, due to the feature of the changed target operational volume-to-capacity ratio embedded in the model. The 64 different neural network based cycle length design models were developed based on simulation data surrogating field data. The CORSIM optimal cycle lengths minimizing delay were found through the COST software developed for the study. COST searches for the CORSIM optimal cycle length minimizing delay with a heuristic searching method, a hybrid genetic algorithm. Among 64 models, the best one producing cycle lengths close enough to the optimal was selected through statistical tests. It was found from the verification test that the best model designs a cycle length as similar pattern to the ones minimizing delay. The cycle lengths from the proposed model are comparable to the ones from TRANSYT-7F.

• Journal of Life Science
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• v.25 no.2
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• pp.237-242
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• 2015

The use of calcite-forming bacteria (CFB) in crack remediation and durability improvements in construction materials creates a permanent and environmentally-friendly material. Therefore, research into this type of application is stimulating interdisciplinary studies between microbiology and architectural engineering. However, the mechanisms giving rise to these materials are dependent on calcite precipitation by the metabolism of the CFB, which raises concerns about possible hazards to cement-based construction due to microbial metabolic acid production. The aim of this study was to determine target microorganisms that possibly can have bio-corrosive effects on cement mortar and to assess multi-functional CFBs for their safe application to cement structures. The chalky test was first used to evaluate the $CaCO_3$ solubilization feature of construction sites by fungi, yeast, bacterial strains. Not all bacterial strains are able to solubilize $CaCO_3$, but C. sphaerospermum KNUC253 or P. prolifica KNUC263 showed $CaCO_3$ solubilization activity. Therefore, these two strains were identified as target microorganisms that require control in cement structures. The registered patented strains Bacillus aryabhatti KNUC205, Arthrobacter nicotianae KNUC2100, B. thuringiensis KNUC2103 and Stenotrophomonas maltophilia KNUC2106, reported as multifunctional CFB (fungal growth inhibition, crack remediation, and water permeability reduction of cement surfaces) and isolated from Dokdo or construction site were unable to solubilize $CaCO_3$. Notably, B. aryabhatti KNUC205 and A. nicotianae KNUC2100 could not hydrolyze cellulose or protein, which can be the major constituent macromolecules of internal materials for buildings. These results show that several reported multi-functional CFB can be applied to cement structures or diverse building environments without corrosive or bio-deteriorative risks.

• Journal of The Korean Association For Science Education
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• v.33 no.6
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• pp.1154-1169
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• 2013

The present work was performed to find behavioral characteristics of elementary school students corresponding to the motivation system on science learning (SL-BIS/BAS; Behavioral Inhibition/Activation System about Science Learning) in the observation situation. Eye-tracking was used for this study, which is one of the neurophysiological methods. The findings of present study were as follows: First, students who have sensitive motivation system to SL-BIS (SL-BIS group) showed meaningfully shorter fixation duration the whole time during an observation task than students who have sensitive motivation system to SL-BAS (SL-BAS group) (p<.05). Total fixation counts of SL-BIS group were significantly larger than SL-BAS group and it indicates that SL-BIS group often generated new fixations. Therefore, fixation duration per count of SL-BAS group was longer than that of SLBIS group. Second, we studied fixations in situations with movement corresponding to the motivation system on science learning. SL-BIS group and SL-BAS group exhibited similar fixation duration in the study task segment with movement, which is one of the stimulus attracting students. However, for the study task segment when the movement was finished, total fixation duration and fixation duration per count of SL-BAS group were meaningfully longer than those of SL-BIS group. Third, comparing fixation targets classified by factors of study task, SL-BIS group showed fixation on the target that is not important for the study task. But SL-BAS group concentrated on the target-related factor of the study task. The present work could be helpful in understanding students' characteristics corresponding to the motivation system on science learning in observation situation and for making a learning & teaching plan that is suitable to the feature of students.

• Korean Journal of Cognitive Science
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• v.33 no.1
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• pp.51-75
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• 2022

Transcranial direct current stimulation (tDCS) is a non-invasive brain stimulation that is able to alter neuronal activity in particular brain regions. Many studies have researched how tDCS modulates neuronal activity and reorganizes neural networks. However it is difficult to conclude the effect of brain stimulation because the studies are heterogeneous with respect to the stimulation parameter as well as individual difference. It is not fully in agreement with the effects of brain stimulation. In particular few studies have researched the reason of variability of brain stimulation in response to time so far. The study investigated individual variability of brain stimulation based on circadian rhythm and chronotype. Participants were divided into two groups which are morning type and evening type. The experiment was conducted by Zoom meeting which is video meeting programs. Participants were sent experiment tool which are Muse(EEG device), tdcs device, cell phone and cell phone holder after manuals for experimental equipment were explained. Participants were required to make a phone in frount of a camera so that experimenter can monitor online EEG data. Two participants who was difficult to use experimental devices experimented in a laboratory setting where experimenter set up devices. For all participants the accuracy of 98% was achieved by SVM using leave one out cross validation in classification in the the effects of morning stimulation and the evening stimulation. For morning type, the accuracy of 92% and 96% was achieved in classification in the morning stimulation and the evening stimulation. For evening type, it was 94% accuracy in classification for the effect of brain stimulation in the morning and the evening. Feature importance was different both in classification in the morning stimulation and the evening stimulation for morning type and evening type. Results indicated that the effect of brain stimulation can be explained with brain state and trait. Our study results noted that the tDCS protocol for target state is manipulated by individual differences as well as target state.

• Journal of Gastric Cancer
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• v.4 no.4
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• pp.207-212
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• 2004

Purpose: Invasion and metastasis in solid tumors require the action of tumor-associated proteases. The serine protease urokinase-type plasminogen (uPA) and receptor (uPAR) appear to have a major function in these processes. Expression of the uPAR is elevated in breast and colon carcinomas, and this is often associated with invasiveness and poor prognosis. The purpose of this study was to determine whether the expression of the uPAR gene correlates with clinico-pathological parameters in human gastric carcinomas. Materials and Methods: We examined the expression of uPAR mRNA by using northern blot analysis and RT-PCR in 35 gastric carcinomas and the surrounding normal mucosa. Macroscopic and histopathological tumor findings and survival rates were obtained from the patient records and from endoscopic, surgical, and pathological reports. Results: The expression of uPAR and was higher in most neoplasms than in the corresponding normal mucosal tissue. uPAR mRNA expression in tumors correlated well with lymph-node metastasis (P<0.02) and tumor stage (P<0.01). The survival rate of patients with tumors displaying high uPAR expression levels was significantly lower (P<0.04) than that of patients without uPAR expression, but IL-8 showed only the tendency of survival difference. Conclusion: These results suggest that uPAR may be an important prognostic factor in human gastric carcinomas.

• Progress in Medical Physics
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• v.23 no.4
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• pp.219-228
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• 2012

The tangential breast intensity modulated radiotherapy (T-B IMRT) technique, which uses the same tangential fields as conventional 3-dimensional conformal radiotherapy (3D-CRT) plans with physical wedges, was analyzed in terms of the calculated dose distribution feature and dosimetric accuracy of beam delivery during treatment. T-B IMRT plans were prepared for 15 patients with breast cancer who were already treated with conventional 3D-CRT. The homogeneity of the dose distribution to the target volume was improved, and the dose delivered to the normal tissues and critical organs was reduced compared with that in 3D-CRT plans. Quality assurance (QA) plans with the appropriate phantoms were used to analyze the dosimetric accuracy of T-B IMRT. An ionization chamber placed at the hole of an acrylic cylindrical phantom was used for the point dose measurement, and the mean error from the calculated dose was $0.7{\pm}1.4%$. The accuracy of the dose distribution was verified with a 2D diode detector array, and the mean pass rate calculated from the gamma evaluation was $97.3{\pm}2.9%$. We confirmed the advantages of a T-B IMRT in the dose distribution and verified the dosimetric accuracy from the QA performance which should still be regarded as an important process even in the simple technique as T-B IMRT in order to maintain a good quality.

• Journal of the Korean Institute of Traditional Landscape Architecture
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• v.30 no.4
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• pp.1-13
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• 2012

Landscape Garden tradition of excellent examples of places that are focused on hydroponics management. South Korea and China, this thing was noticeable among them South Korea which emphasizes the natural contours of the natural streams in accordance with the basic idea to use examples that feature will do. Gardens in China by constructing a flat terrain also naturally expect to find examples of conscious ideas depending on the water and the mountains are characterized. These differences and similarities through the Gardens of the tradition of separating the two countries to build their Garden by site Soswaewon and Zolzengwon appear in the target hand is to identify the characteristics between the director. Research methods literature survey, field survey of the natural environment through the plantation, background history, the people who intend to study, to configure the ground water space, Jian, construction and management has been studied in hydroponics. As a result, Damyang-gun, Jeollanam-do, South Korea in the Garden of the Soswaewon(瀟灑園) organization with inner garden and outer garden of a small, but the scale of production to Yang San-Bo's 'eunilgwan' implement security based rock mooring takes the form of a linear channel and the water came down from riding pending to avoid artifacts gathered again took the form of streams flowing into that. Hutton was a rubble pile structure Jian. Building an Gwangpunggak, Jewoldang, as Daebongdae consist, respectively, depending on the purpose of the mooring was deployed by focusing. The other hand, is located at Suzhou, Jiangsu of China Zolzengwon(拙政園) flat terrain is located on. Largely divided eastern gardens, Central Gardens and the Gardens of the West was conducted by five thirds of the total area of Water accounted for. Pavilion the center of the pond, Seokgasan achieve a variety of landscapes and architectural features that are most of the Ming. The two countries, each region's natural environment and human environment, different, unique characteristics to each other in the implementation of a unique hydroponic Garden tube and ideological backgrounds, but especially the 'eunilgwan' and the terrain that is divided according to the conditions of this study, so fulfilling Garden was conducted.

• Journal of Intelligence and Information Systems
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• v.27 no.4
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• pp.23-48
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• 2021

The Korean economy has achieved continuous economic growth for the past several decades thanks to the government's export strategy policy. This increase in exports is playing a leading role in driving Korea's economic growth by improving economic efficiency, creating jobs, and promoting technology development. Traditionally, the main factors affecting Korea's exports can be found from two perspectives: economic factors and industrial structural factors. First, economic factors are related to exchange rates and global economic fluctuations. The impact of the exchange rate on Korea's exports depends on the exchange rate level and exchange rate volatility. Global economic fluctuations affect global import demand, which is an absolute factor influencing Korea's exports. Second, industrial structural factors are unique characteristics that occur depending on industries or products, such as slow international division of labor, increased domestic substitution of certain imported goods by China, and changes in overseas production patterns of major export industries. Looking at the most recent studies related to global exchanges, several literatures show the importance of cultural aspects as well as economic and industrial structural factors. Therefore, this study attempted to develop a forecasting model by considering cultural factors along with economic and industrial structural factors in calculating the import volume of each country from Korea. In particular, this study approaches the influence of cultural factors on imports of Korean products from the perspective of PUSH-PULL framework. The PUSH dimension is a perspective that Korea develops and actively promotes its own brand and can be defined as the degree of interest in each country for Korean brands represented by K-POP, K-FOOD, and K-CULTURE. In addition, the PULL dimension is a perspective centered on the cultural and psychological characteristics of the people of each country. This can be defined as how much they are inclined to accept Korean Flow as each country's cultural code represented by the country's governance system, masculinity, risk avoidance, and short-term/long-term orientation. The unique feature of this study is that the proposed final prediction model can be selected based on Design Principles. The design principles we presented are as follows. 1) A model was developed to reflect interest in Korea and cultural characteristics through newly added data sources. 2) It was designed in a practical and convenient way so that the forecast value can be immediately recalled by inputting changes in economic factors, item code and country code. 3) In order to derive theoretically meaningful results, an algorithm was selected that can interpret the relationship between the input and the target variable. This study can suggest meaningful implications from the technical, economic and policy aspects, and is expected to make a meaningful contribution to the export support strategies of small and medium-sized enterprises by using the import forecasting model.

• Journal of the Korean Institute of Landscape Architecture
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• v.52 no.1
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• pp.17-33
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• 2024

This study suggests management planning of Bonguisan Neighborhood Park located on the central of Chuncheon city and highly used for citizen's rest and leisure space utilizing its vegetation structure feature. Bonguisan has been the central of the chuncheon since the period of the Three states in Korean history and consistently damaged, especially in present era, an isolation and sererance of its ecosystem has deepen for indiscreet urban development. The percentage of actual vegetation of Boinguisan Neighborhood Park is as follows: Quercus mongolica is 28.5%, Quercus mongolica - Quercus serrata is 2.1%, Pinus densiflora is 15.6%, Pinus densiflora - Quercus mongolica is 15.9%, Betula schmidtii is 1.6%, Robinia pseudoacacia is 5.9%, Pinus koraiensis is 1.6%. Quercus mongolica is distributed on the southwest, northwest, southeast side of region, Pinus densiflora is distributed on the ridge of east and southeast side of region, Betula schmidtii is distributed on the valley of northeast side region and steep slope region which is on the north side of chungwonsa temple. Pinus densiflora community (Comm. I) and Quercus acutissima - Robinia pseudoacacia community (Comm. V) is expected to undergo succession since it's categorized as Quercus spp. and Quercus mongolica community (Comm. II) and Quercus serrata-Quercus mongolica community (Comm. III), Betula schmidtii community (Comm. IV), Pinus koraiensis community (Comm. VI) is expected to maintain. Also for target vegetation and management planning, Vegetation of Bonguisan Neighborhood Park is classified as 1st Natural landscape conservation and improvement type, 2nd Ecological succession type, 3rd Unusual community conservation type, and 4th Recreation and experience type. And we suggested ecological management measure about each management types. For efficient management of Bonguisan Neighborhood Park, it is need to unify management system of it and after designating Pinus densiflora community and Betula schmidtii community which has high ecological preservation value as an ecological landscape protected area and manage it.