• The Korean Journal of Applied Statistics
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• v.16 no.1
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• pp.87-100
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• 2003

Most of statistical data are generated by a set of dynamic, stochastic, and simultaneous relations. An important question is how to specify statistical models so that they are consistent with the dynamic feature of those data. A general hypothesis is that the lagged effect of a change in an explanatory variable is not felt all at once at a single point in time, but The impact is distributed over a number of future points in time. In other words, current control variables are determined by a function that can be reduced to a distributed lag function of past observations. It is possible to explain the relationship between variables in different points of time and to estimate the long-run impacts of a change in a variable on another if time lag series of explanatory variables are incorporated in the model specification. In this study, distributed lag structure is applied to the domestic stock market model to capture the dynamic response of the market by exogenous shocks. The Domestic market is found more responsive to the changes in foreign market factors both in the short and the long run.

• Journal of Convergence for Information Technology
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• v.9 no.3
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• pp.128-133
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• 2019

The purpose of this study is to verify whether the data measured by the researcher and the smart shoe sensor data are the same or similar by performing the 6 - minute walking test and time up and go test after putting smart shoes on a normal person. Ten normal adult males participated. After wearing smart shoes, they performed a 6-minute walk test and a time up and go test. The results of this experiment show that the accuracy of the current sensor is high. The difference in the distance of the 6-minute walking test is that the difference is because the turning point, which is not calculated in the actual 30-m track, measures the distance. From this point of view, it can be seen that smart shoes measure more accurate distance and it is expected that various tests will be possible through smart sensors.

• Journal of the Society of Naval Architects of Korea
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• v.59 no.6
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• pp.423-431
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• 2022

In this paper, the results of Planar Motion Mechanism (PMM) test for a 1/15 scaled model of the MARIN Joubert BB2 submarine is dealt with to derive the maneuvering coefficients for surface condition. For the depth of surface navigation, the top of the sail was exposed 0.46 m above the water surface in the model scale, and it corresponds to 6.9 m in the full scale. The resistance and self-propulsion tests were conducted, and the model's self-propulsion point was obtained for 1.328 m/s, which corresponded to 10 knots in the full scale. The maneuvering tests were performed at the model's self-propulsion point, and the maneuvering coefficients were obtained. Based on the maneuvering coefficients, a turning simulation was performed for starboard 30 degree of stern fins. The straight-line stability and control effectiveness in the horizontal plane were analyzed using the maneuvering coefficients and compared with the appropriate range. For the analysis of the neutral fin angle of the X-type stern fin, the stern fin test with drift angles was carried out. As a result, the flow straightening effect at lower and upper parts of the stern fin was discussed.

• Journal of Gastric Cancer
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• v.19 no.4
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• pp.438-450
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• 2019

Purpose: Although linear-shaped gastroduodenostomy (LSGD) was reported to be a feasible and reliable method of Billroth I anastomosis in patients undergoing totally laparoscopic distal gastrectomy (TLDG), the feasibility of LSGD for patients undergoing totally robotic distal gastrectomy (TRDG) has not been determined. This study compared the feasibility of LSGD in patients undergoing TRDG and TLDG. Materials and Methods: All c: onsecutive patients who underwent LSGD after distal gastrectomy for gastric cancer between January 2009 and December 2017 were analyzed retrospectively. Propensity score matching (PSM) analysis was performed to reduce the selection bias between TRDG and TLDG. Short-term outcomes, functional outcomes, learning curve, and risk factors for postoperative complications were analyzed. Results: This analysis included 414 patients, of whom 275 underwent laparoscopy and 139 underwent robotic surgery. PSM analysis showed that operation time was significantly longer (163.5 vs. 132.1 minutes, P<0.001) and postoperative hospital stay significantly shorter (6.2 vs. 7.5 days, P<0.003) in patients who underwent TRDG than in patients who underwent TLDG. Operation time was the independent risk factor for LSGD after intracorporeal gastroduodenostomy. Cumulative sum analysis showed no definitive turning point in the TRDG learning curve. Long-term endoscopic findings revealed similar results in the two groups, but bile reflux at 5 years showed significantly better improvement in the TLDG group than in the TRDG group (P=0.016). Conclusions: LSGD is feasible in TRDG, with short-term and long-term outcomes comparable to that in TLDG. LSGD may be a good option for intracorporeal Billroth I anastomosis in patients undergoing TRDG.

• Journal of the Korea Institute of Information and Communication Engineering
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• v.18 no.7
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• pp.1764-1776
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• 2014

This study is the context about an introduction of a bookkeeping by double entry & accrual base accounting which is the turning point of National Accounting and defense integrated financial management which is delivered following system Digital Budget Accounting system, in other words about something to do with the improvement of efficiency of financial information data. National defense Integration Financial Information system (NDIFIS) facilitates Project program management and makes the whole process of Defense financial Business manageable in one system. Also, there is a purpose to increase the credibility and transparency of National defense finances by providing internal and external information users with credible financial statements and cost materials. By using data envelopment analysis (DEA) which is a useful method to measuring the efficiency of organization, this study aims to improve the financial information data efficiency by comparing the efficiency of the same type troops and when it comes to the inefficient troops, by offering the certain objective of efficiency.

• Architectural research
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• v.25 no.4
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• pp.61-72
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• 2023

The main factors that made Seoul's rapid population accommodation and urbanization possible in the mid-to-late 20th century were the ex-pansion of urban infrastructure, completion of the transportation system, and housing supply. The development of transportation and resi-dential development occurred simultaneously, and in particular, apartment complexes, a representative residential area in Seoul, were most influenced by Perry's neighborhood unit theory. The purpose of this study is to analyze the process of the physical environment of apartment complexes in the metropolitan area in response to development of transportation in the mid-to-late 20th century. The analysis sites are Jamsil Apartment Complex(1974), Dunchon Apartment Complex(1979), Mok-dong New Town(1983), Sanggye New Town(1985), Bundang New-town(1990) and Ilsan Newtown(1990), which were planned at the turning point of development of transportation and actively reflect the neigh-borhood unit theory. The analysis was conducted in three stages. Analyzing the status of transportation when the plan was established, deriv-ing the planning elements, and classifying the planning elements into walking, bus, car, and subway which is the representative transportation. The conclusions from the analysis are as follows. Firstly, completing the legal system and expanding the related infrastructure are essential. Secondly, in contrast to the increase in traffic volume, the pedestrian environment has been continuously improved. Thirdly, despite the emergence of new mode of transportation, there was a tendency to activate the linkage between transportation.

• The Journal of the Korea Contents Association
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• v.21 no.12
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• pp.95-106
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• 2021

The purpose of this study is to derive major topics in content R&D and provide directions for academic development by exploring research trends over the past 20 years using topic modeling targeting 9,858 papers published in the Journal of the Korean Contents Association. To secure the reliability and validity of the extracted topics, not only the quantitative evaluation technique but also the qualitative technique were applied step-by-step and repeated until a corpus of the level agreed upon by the researchers was generated, and detailed analysis procedures were presented accordingly. As a result of the analysis, 8 core topics were extracted. This shows that the Korean Contents Association is publishing convergence and complex research papers in various fields without limiting to a specific academic field. Also, before 2012, the proportion of topics in the field of engineering and technology appeared relatively high, while after 2012, the proportion of topics in the field of social sciences appeared relatively high. Specifically, the topic of 'social welfare' showed a fourfold increase in the second half compared to the first half. Through topic-specific trend analysis, we focused on the turning point in time at which the inflection point of the trend line appeared, explored the external variables that affected the research trend of the topic, and identified the relationship between the topic and the external variable. It is hoped that the results of this study can provide implications for active discussions in domestic content-related R&D and industrial fields.

• Journal of Digital Contents Society
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• v.2 no.2
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• pp.199-208
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• 2001

The industries of culture contents is the trend to enforce the power of National competitions in the world economy knowledge foundation which tries to exchange a labor industry to the knowledge business. The spread of internet is the apparently turning point to be devide the world economy into the industrial society and the digital society. Also the communication with internet has been recognized as it is not any more newly means of communication in Korea. Net value which is a multinational internet survey corporation clarified that Korea was the most nation in the world by the result of its research in the rate of using internet. This research look into the characteristic of the media and type of the animation in internet, also analysis a need of user and a degree of convenience of using internet in the web of education site. This study is designed to study the evaluation criteria of web interface with visual perception and to seek its development in relation to the quality of visual perception in case of web animation.

• The Journal of the Korea Contents Association
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• v.20 no.9
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• pp.271-284
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• 2020

Good reviews that Half-Life: Alyx received created a turning point for the vitalization of the VR market with an uncertain future due to the absence of a revenue model together with the increased sales of VR equipment. Based on previous studies, this study categorized the characteristics of VR games according to graphs, first-person system, interface, controller, interaction technology, sound and stories. The analysis results show that the seven elements corresponded with "interactions" and "virtual images," which represent the completion level of games as part of VR components, and were connected to one another, which led to the proposal of an upper-rank concept "presence" to put them together. "Immersiveness," which represents users' emotions as part of VR components, was analyzed with the immersion theory to assign tasks of proper difficulty level for users' abilities. In the research process, the Delphi technique and FGI were administered to a panel of 15 experts to ensure objectivity. Finally, "presence" and "immersiveness" are characteristics in proportion to each other and can be valid concepts in future analysis of VR games as well as Half-Life: Alyx, which led to the proposal a new concept framework called 'presence effects' by combining the two words.

• Journal of Korean Society of Steel Construction
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• v.12 no.1 s.44
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• pp.1-8
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• 2000

In this study, the effect of semi-rigid connections on the structural behavior of 20-story braced steel structure has been investigated utilizing the second-order elastic structural analysis program in which nonlinear behavior of beam-column connections and geometric nonlinearity have been considered. Global effects such as P-delta effect and sway at the top have been studied, as well as distribution of member force and combined stress in structural members as local effects. When the structure subjected to horizontal load and vertical load is equipped with lateral-load resisting system such as braces, replacement of shear connection with semi-rigid connection has not caused any problem in P-delta effect and top lateral displacement. Distribution of member forces resulted in reduction in member size for economic structural design.