• Journal of Space Technology and Applications
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• v.1 no.1
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• pp.23-32
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• 2021

The high-level Space Situational Awareness (SSA) objective is to provide to the users dependable, accurate and timely information in order to support risk management on orbit and during re-entry and support safe and secure operation of space assets and related services. Therefore the risk assessment for the re-entry of space objects should be managed nationally. In this research, the Software for Re-Entry Prediction of space objects (SREP) was developed for national SSA system. In particular, the rate of change of the drag coefficient is estimated through a newly proposed Drag Scale Factor Estimation (DSFE), and is used for high-precision orbit propagator (HPOP) up to an altitude of 100 km to predict the re-entry time and position of the space object. The effectiveness of this re-entry prediction is shown through the re-entry time window and ground track of space objects falling in real events, Grace-1, Grace-2, Tiangong-1, and Chang Zheng-5B Rocket body. As a result, through analysis 12 hours before the final re-entry time, it is shown that the re-entry time window and crash time can be accurately predicted with an error of less than 20 minutes.

• The Journal of the Korea Contents Association
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• v.22 no.9
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• pp.260-270
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• 2022

With the revision of the 「State Property Act」, the conditions for using state-owned land have improved. The new government is also suggesting the necessity of using state-owned land to revitalize private investment and secure financial investment capacity. In line with these policy changes, this study examines Japan's policy on the utilization of state-owned land and effective use cases, and seeks to find policy implications from the perspective of managing and promoting the use of state-owned land. The direction of Japan's public land utilization policy is to induce optimal use of state-owned land through efficient management, and to increase the value of state property by promoting active use of state-owned land through linkage of state-owned and public land and private participation, etc. It appears that the policy is being pursued in the direction of suppressing the sale of state-owned land in the country. To promote the effective use of state-owned land, it is necessary to establish a clear policy direction first. In addition, the establishment of a transparent information disclosure system and the establishment of a strong control tower capable of coordinating interests between ministries are required. The starting point of policy establishment for efficient use of state-owned land is to change the perception that the actual owner of state-owned land is the people.

• Journal of the Korean Society of Surveying, Geodesy, Photogrammetry and Cartography
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• v.40 no.5
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• pp.449-456
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• 2022

This study proposes a deep learning algorithm to predict crop yield using GIS (Geographic Information System) to extract soil properties from Soilgrids and soil suitability class maps. The proposed model modified the structure of a published CNN-RNN (Convolutional Neural Network-Recurrent Neural Network) based crop yield prediction model suitable for the domestic crop environment. The existing model has two characteristics. The first is that it replaces the original yield with the average yield of the year, and the second is that it trains the data of the predicted year. The new model uses the original field value to ensure accuracy, and the network structure has been improved so that it can train only with data prior to the year to be predicted. The proposed model predicted the yield per unit area of autumn cabbage for kimchi by region based on weather, soil, soil suitability classes, and yield data from 1980 to 2020. As a result of computing and predicting data for each of the four years from 2018 to 2021, the error amount for the test data set was about 10%, enabling accurate yield prediction, especially in regions with a large proportion of total yield. In addition, both the proposed model and the existing model show that the error gradually decreases as the number of years of training data increases, resulting in improved general-purpose performance as the number of training data increases.

• The Journal of the Acoustical Society of Korea
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• v.41 no.5
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• pp.570-588
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• 2022

We scrutinized the acoustic outputs from the 70 shock wave generators of the 15 product models whose technical documents were available, among the 46 ballistic extracorporeal shock wave therapeutic devices of 11 domestic and 6 foreign manufacturers, approved by the Minster of Food & Drug Safety (Rep. Korea). We found that the acoustic Energy Flux Density (EFD), the most popular exposure parameter, was different by up to 563.64 times among shock wave generators at their minimum output settings and by up to 74.62 times at their maximum settings. In the same product model, the EFD was shown to vary depending on shock wave transmitters by up to 81.82 times at its minimum output setting and by up to 46.15 times at its maximum setting. The lowest EFD 0.013 mJ/mm² at the maximum output settings was much lower (2.1 %) than the maximum value 0.62 mJ/mm² at the minimum settings. The Large acoustic output differences (tens to hundreds of times)from the therapeutic devices approved for the same clinical indications imply that their therapeutic efficacy & safety may not be assured. The findings suggest the regulatory authority to revise her guideline to give clearer criteria for clinical approval and equality in performance, and recommend the authority to initiate a post-approval surveillance as well as a test in conformance between the data in technical documents and the real acoustic outputs clinically used.

• The Korean Journal of Archival Studies
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• no.69
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• pp.7-33
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• 2021

From the beginning of the enactment and implementation of the Public Records Management Act, there has been a steady discussion on the establishment of local archives. Local archives include not only administrative records of local governments, but also private archives such as containing the lives of residents. Along with the academic discussion, there have been movements for local autonomy and decentralization. Currently, interest and discussion on private archiving are in the historical flow. In addition, private archiving has become a social concern because of the establishment of systems such as the Public Records Management Act and the Information Disclosure Act, the establishment of a digital environment, and the spread of the meaning and value of village community activities. There are several government agencies related to private archiving, and the grounds for performing their work are different, and there are many central administrative agencies to which they belong. Therefore, I propose that the National Archives take the lead and form a 'Consortium of Private archives Management Institutions'. The organization should promote first, cooperation of collection information and archives, second, coordination of tasks and functions between institutions, and third, establishment of a nationwide private archives management system. Now is our chance. Instead of reacting on an ad hoc basis, respond systematically with a long-term perspective.

• Journal of Aerospace System Engineering
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• v.16 no.4
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• pp.95-108
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• 2022

Airworthiness certification is critical, in ensuring the flight safety of military aircraft for development tests and production operations. The MIL-HDBK-516C, latest airworthiness certification document, handles the field of flying qualities in Chapter 6 (flight technology), and refers to specific chapters of MIL-STD-1797B, which is the specification document for developing military aircraft. Since the MIL-STD-1797B released in 2006 by the U.S. Department of Defense is not disclosed to other countries, the Chapter 6 (flight technology) of MIL-HDBK-516B Expanded, the former certification standards pursuant to flying qualities, has to be applied to military aircraft being developed in the Republic of Korea. However the requirements of Chapter 6 of MIL-HDBK-516B Expanded comprise unclear sentences, because of contents from various development specifications. Also, clarification is needed in that the same requirements have to be verified in different criteria. In this paper, the results of this study present an effective verification method, for acquiring the airworthiness certification in field of flying qualities based on MIL-HDBK-516B Expanded.

• The Korean Journal of Applied Statistics
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• v.35 no.3
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• pp.407-419
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• 2022

The semiconductor fabrication process is complex and time-consuming. There are sometimes errors in the process, which results in defective die on the wafer bin map (WBM). We can detect the faulty WBM by finding some patterns caused by dies. When one manually seeks the failure on WBM, it takes a long time due to the enormous number of WBMs. We suggest a two-step approach to discover the probable pattern on the WBMs in this paper. The first step is to separate the normal WBMs from the defective WBMs. We adapt a hierarchical clustering for de-noising, which nicely performs this work by wisely tuning the number of minimum points and the cutting height. Once declared as a faulty WBM, then it moves to the next step. In the second step, we classify the patterns among the defective WBMs. For this purpose, we extract features from the WBM. Then machine learning algorithm classifies the pattern. We use a real WBM data set (WM-811K) released by Taiwan semiconductor manufacturing company.

• Journal of Environmental Impact Assessment
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• v.32 no.4
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• pp.203-213
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• 2023

The AERMOD model was the most used, accounting for 89.0%, based on the analysis of the environmental impact assessment reports published in the Environmental Impact Assessment Information Support System (EIASS) between 2021 and 2022. The mismatch of versions between AERMET and AERMOD was found to be 25.3%. There was the operational time discrepancy of 50.6% from industrial complexes, urban development projects between used in the model and applied in estimating pollutant emissions. The results of applying various versions of the AERMET and AERMOD models to both area sources and point sources in both simple and complex terrain in the Gunsan area showed similar values after AERMOD version 12 (15181). Emissions are assessed as 24-hour operation, and the predicted concentration in both simple and complex terrain when using the variable emission coefficient option that applies an 8-hour daytime operation in the model is lowered by 37.42% ~ 74.27% for area sources and by 32.06% ~ 54.45% for point sources. Therefore, to prevent the error in using the variable emission coefficient, it is required to clearly present the emission calculation process and provide a detailed explanation of the composition of modeling input data in the environmental impact assessment reports. Also, thorough reviews by special institutions are essential.

• The Journal of Korean-Japanese National Studies
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• no.21
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• pp.1-43
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• 2011

This article introduces Abe Mituie's activities related to Korean and Japanese Buddhism and two newly discovered materials. He worked as a brain of Japanese cultural rule over Joseon Korea while holding various positions such as the president of KyeongSung Il Bo, the vice president of Kokmin Newspaper and the director of Central Joseon Association. Abe was responsible for Enkak Temple, the head temple of Japanese Rinzai section, and was one of the layman followers of Syak Soen who worked for the spread of modern Japanese Buddhism to Europe and America. He was a respectful Buddhist layman so as to teach Zen Buddhism for young Buddhist monks in Japan. After he started to assume charge in the Kyeong Sung Il Bo, he was also very active in movements in relation to Joseon Buddhism to the extent that he was found to be deeply involved in Joseon Buddhism sections. On the other hand, he concluded Joseon culture to be 'devastated.' He asserted that it was necessary to develop spiritual culture and revive Buddhism in order to resolve the devastation in the Joseon. In addition, he thought that Joseon Buddhism was ruined due to the misgovernment of the Joseon Dynasty, but had its own as great tradition as Japanese Buddhism. Therefore, in his opinion, there was a need to do research on Joseon Buddhism and find some way out of the contemporary difficulties. In order to save the situation, he made efforts to protect and revive Joseon Buddhism while paying continuous visits to Joseon Buddhist temples, supporting the publication of Buddhist canons and proposing to have a regular meeting of 'The Invitation of 30 Head Temples.' From his visit to Youngju Temple and his consistent relationship with Kang Daeryeon, it can be assumed that he was involved in reorganizing power structure in Joseon Buddhism and establishing various institutions. He emphasized the strict adherence of individuals and communities to rules in his lecture for students at Jung Ang Hak Rim. It was a way to revive Joseon Buddhism by creating a new social image of Joseon Buddhism. He continued to work for the restoration of Joseon Buddhism even after he retired from Kyeong Sung Il Bo and returned to Japan. He introduced the originality of Joseon Buddhism history to Japan and sent Japanese monks to Korea in order to do research and contribute to exchange between Korean and Japanese Buddhism. All things taken together, it is evident that Abe Mitzihe regarded Joseon as backward or stagnant from a perspective of evolutionist or orientalist, and was a Japanese elite to believe that it was just for Japan to control Korea. However, he was different from other Japanese elites in that he did not considered Joseon Buddhism merely as the object of propagation. He thought that Joseon Buddhism possessed its own great tradition and culture, but was ruined because of the misadministration of the Joseon Royal House. Therefore, in his opinion, Joseon Buddhism should be recovered by means of some supports, and its revival would lead to the restoration of Joseon culture as a whole, which would be realized by Japanese rule over Korea and Japanese elites' generous assistance.

• Proceedings of the Korean Institute of Information and Commucation Sciences Conference
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• 2022.05a
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• pp.377-380
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• 2022

An application called an app can be downloaded and used on mobile devices. Among them, Android-based apps have the disadvantage of being implemented on an open source basis and can be exploited by anyone, but unlike iOS, which discloses only a small part of the source code, Android is implemented as an open source, so it can analyze the code. However, since anyone can participate in changing the source code of open source-based Android apps, the number of malicious codes increases and types are bound to vary. Malicious codes that increase exponentially in a short period of time are difficult for humans to detect one by one, so it is efficient to use a technique to detect malicious codes using AI. Most of the existing malicious app detection methods are to extract Features and detect malicious apps. Therefore, three ways to select the optimal feature to be used for learning after feature extraction are proposed. Finally, in the step of modeling with optimal features, ensemble techniques are used in addition to a single model. Ensemble techniques have already shown results beyond the performance of a single model, as has been shown in several studies. Therefore, this paper presents a plan to select the optimal feature and implement a learning model for Android app-based malicious code detection.