• Korean Journal of Construction Engineering and Management
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• v.24 no.1
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• pp.40-50
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• 2023

Quality control (QC) is an essential work for the successful construction project execution. Recently, robust application of ICT to the QC tasks leads to utilizing innovative technologies and equipment. However, overall planing of QC works needs to take place before applying new technologies to each and individual QC task. The objectives of this research involve developing a database and an algorithm that identifies QC tasks and related information upfront. In addition, the researchers developed a methodology to generate inspection tasks in conjunction with construction work tasks. The Korean Ministry of Land and Transportation provides standard supervision checklists. They were classified based on criteria of inspection items, methods, period and the scope. Reinforced concrete work was selected as a case study for validation of the method. This framework can function when planing construction tasks with any type of planning tools and innovative technologies. The researchers expect this framework may contribute to various construction projects when developing QC plans and tasks with applicable technologies.

• Korean Journal of Remote Sensing
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• v.39 no.2
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• pp.223-232
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• 2023

A widely used method for monitoring land cover using high-resolution satellite images is to classify the images based on the colors of the objects of interest. In urban areas, not only major objects such as buildings and roads but also vegetation such as trees frequently appear in high-resolution satellite images. However, the colors of vegetation objects often resemble those of other objects such as buildings, roads, and shadows, making it difficult to accurately classify objects based solely on color information. In this study, we propose a method that can accurately classify not only objects with various colors such as buildings but also vegetation objects. The proposed method uses the normalized difference vegetation index (NDVI) image, which is useful for detecting vegetation objects, along with the RGB image and classifies objects into subclasses. The subclass classification results are fused, and the final classification result is generated by combining them with the image segmentation results. In experiments using Compact Advanced Satellite 500-1 imagery, the proposed method, which applies the NDVI and subclass classification together, showed an overall accuracy of 87.42%, while the overall accuracy of the subchannel classification technique without using the NDVI and the subclass classification technique alone were 73.18% and 81.79%, respectively.

• KSCE Journal of Civil and Environmental Engineering Research
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• v.28 no.6B
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• pp.709-721
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• 2008

This paper is to test the applicability of ModKIMSTORM (Modified KIneMatic Wave STOrm Runoff Model) by applying it to Namgangdam watershed of $2,293km^2$. Model inputs (DEM, land use, soil related information) were prepared in 500 m spatial resolution. Using five typhoon events (Saomi in 2000, Rusa in 2002, Maemi in 2003, Megi in 2004 and Ewiniar in 2006) and two storm events (May of 2003 and July of 2004), the model was calibrated and verified by comparing the simulated streamflow with the observed one at the outlet of the watershed. The Pearson's coefficient of determination $R^2$, Nash and Sutcliffe model efficiency E, the deviation of runoff volumes $D_v$, relative error of the peak runoff rate $EQ_p$, and absolute error of the time to peak runoff $ET_p$ showed the average value of 0.984, 0.981, 3.63%, 0.003, and 0.48 hr for 4 storms calibration and 0.937, 0.895, 8.08%, 0.138, and 0.73 hr for 3 storms verification respectively. Among the model parameters, the stream Manning's roughness coefficient was the most sensitive for peak runoff and the initial soil moisture content was highly sensitive for runoff volume fitting. We could look into the behavior of hyrologic components from the spatial results during the storm periods and get some clue for the watershed management by storms.

• Journal of Practical Agriculture & Fisheries Research
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• v.17 no.1
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• pp.163-179
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• 2015

The aim of this study is to investigate to which degree farmers did the crop switching and cultivar renewal as a confrontational strategy to climate change, and which problems they had in that process, and then to provide the supporting plans for them. We conducted a questionnaire survey of 15 citrus farmers of the KNCAP graduates in Jeju Island. Most of the survey respondents agreed to the climate change of Jeju Island and the subtropical climate of its coastal area. The farmers have experienced irregular weather such as abnormal high temperature, frequent rain, and droughts, resulting in the harmful insects and new weeds attack. As the climate change strategies, they are adopting a greenhouse culture system, improving a soil drainage using reorganization of planting space, making a new pest management program, and trying to switch a crop to subtropical fruits. It is expected that 50% of the survey respondents have changed their crops or will do; and 73 % of them have changed cultivar or have a plan to do. Only a few farmers directly pointed to a reason for their efforts to change the crops or to renew the cultivars as the anti-climate change strategy, however, most farmers answered the reason was to increase profitability by meeting their consumers' tastes. Presently, it is not the anti-climate change strategy but increase of profitability by meeting the consumers' needs the reason why most of the survey respondents have changed their crops or renewed the cultivars, while a few of them switched their crops to a subtropical fruit trees due to climate change. On the crop switching, they had some difficulties such as a labor shortage, availability of land, operating costs and instable income. On the cultivar renewal, also, they encountered the lack of cultivating techniques for new cultivars and the dim future for the new market. In long-term perspective, Jeju's farmers need new information and educational programs about the effect of climate change on agriculture of Jeju, and cultivation techniques for new crops and new cultivars.

• Journal of Korea Port Economic Association
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• v.39 no.3
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• pp.33-46
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• 2023

The Autonomous ships are equipped with a function to judge and navigate the sea conditions on their own, so the job of the ship officer who operates it changes. The educational curriculum to nurture ship officer with the ability to operate and manage autonomous ships must also be changed. This study aimed to develop the curriculum for training autonomous ship officer by using the Delphi survey method suitable for predicting the uncertain future. Among the current 61 subjects for training ship officer identified in the Delphi survey, 32 subjects with high importance should be maintained in the training for autonomous ship officer, and subjects with low importance should be abolished or integrated into other subjects. These subjects were collectively referred to as 'general courses'. The expert panel of the Delphi survey suggested 42 items as new subjects, with 18 items of 'high', 14 items of 'middle', and 10 items of 'low'. Through in-depth analysis of these items by experts, 27 subjects were adjusted and three courses were proposed : 1)'Basic course(10 courses)' for developing basic capabilities such as basic theories for understanding advanced technology and information applied to autonomous ships, 2)'Job course(10 courses)' for practical competency directly related to autonomous ship operation, 3)'Intensive course(7 subjects)' for fostering land remote operators of autonomous ships. Since the introduction and spread of autonomous ships will progress rapidly, research to develop and supplement autonomous ship pilot training courses should be continued by reflecting the level of autonomous navigation of autonomous ships.

• Journal of Cadastre & Land InformatiX
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• v.53 no.2
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• pp.53-66
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• 2023

Recently, there has been a significant interest in the development of autonomous driving simulation environment based on digital twin. In the development of such digital twin-based simulation environment, many researches has been conducted not only performance and functionality validation of autonomous driving, but also generation of virtual training data for deep learning. However, such digital twin-based autonomous driving simulation system has the problem of requiring a significant amount of time and cost for the system development and the data construction. Therefore, in this research, we aim to propose a method for rapidly designing and implementing a digital twin-based autonomous driving simulation system, using only the existing 3D models and high-definition map. Specifically, we propose a method for integrating 3D model of FBX and NGII HD Map for the Busan EDC area into CARLA, and a method for adding and modifying CARLA functions. The results of this research show that it is possible to rapidly design and implement the simulation system at a low cost by using the existing 3D models and NGII HD map. Also, the results show that our system can support various functions such as simulation scenario configuration, user-defined driving, and real-time simulation of traffic light states. We expect that usability of the system will be significantly improved when it is applied to broader geographical area in the future.

• Journal of Cadastre & Land InformatiX
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• v.53 no.2
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• pp.79-92
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• 2023

With a growing interest in the Han River Skyline, which greatly influences Seoul's image, careful consideration of the skyline form has become crucial in the redevelopment plans for apartment complexes along the Han River. The Seoul Metropolitan City government has lifted the height limitations for apartments along the Hang River to cultivate a vibrant skyline. However, traditional skyline analysis often overlooks specific attributes, limiting the provision of precise guidelines for Seoul's unique skyline plans. Despite advancements in Digital Twin technology, only some tools effectively manage urban skylines with preferred shapes. Hence, this study aims to make a substantial contribution to the advancement of a Digital Twin 3D modeling program capable of effectively managing urban skylines. This is achieved through the utilisation of Conjoint Analysis, which assesses the importance of each attribute in determining the preferred skyline shape. Focusing on Apgujeong apartment complexes along the Han River currently undergoing redevelopment or planned for redevelopment, the study analyses the preferred skyline shape to propose standards for the Digital Twin 3D modeling program development. It also suggests that Conjoint Analysis can be beneficial in this process.

• Korean Journal of Environment and Ecology
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• v.38 no.2
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• pp.178-188
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• 2024

The dynamics of suspended sediment (SS) in forested catchments vary depending upon human or natural disturbances, including land use change, forestry activity, forest fires, and landslides. Understanding the dynamics of SS originating from the potential sources within a forested catchment is crucial for establishing an effective water quality management strategy. Therefore, to suggest a systematic method for interpreting SS dynamics, we evaluated the performance and applicability of ten methods for calculating the hysteresis index based on observed hydrological data and two calculation models (Lawler's method and Lloyd's method) with five sampling intervals (50th, 25th, 10th, 5th, and 1st percentiles). Our results showed that Lloyd's method, which used a sampling interval at the 1st percentile, had the largest number of analyzable runoff events and exhibited the best performance. The results of this study can contribute to quantifying the hysteresis in the relationship between discharge and SS and provide useful information for interpreting SS dynamics.

• Journal of Cadastre & Land InformatiX
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• v.54 no.1
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• pp.49-61
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• 2024

South Korea faces a declining population and rural areas vanishing due to urbanization. Infrastructure, especially medical facilities, may not be sustainable for a long-term. This may impact vulnerable groups like children, teens, and the elderly, worsened by an aging population and low birth rates. Gangwon-do, notably Chuncheon-si, suffers from rural depopulation and poor healthcare self-sufficiency. In this paper, using 2SFCA(Two-Step Floating Catchment Area), we analyze healthcare access in Chuncheon-si, identifying gaps and vulnerable areas. LISA analysis helps map medical vulnerability, considering patient demand and supply. The Gini coefficient assesses spatial inequality. We propose distributing healthcare services and personnel based on age and region. The aim is to identify locations for additional hospitals catering to the elders, Infants, Children, and Adolescents,considering spatial accessibility.

• Journal of the Korean Society of Marine Environment & Safety
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• v.30 no.4
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• pp.340-347
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• 2024

In this study, an expert survey was conducted using the Delphi technique to select items and indicators for evaluation before installing educational facilities in the marine fisheries safety field, in which the educational infrastructure gap between regions is wide. Seven indicators were selected as geographic, social, and administrative factors. In order to objectively evaluate each indicator, evaluation indicators that could be evaluated using public data such as the "Comprehensive National Balanced Development Information System" and "National Statistical Portal" were developed. The Analytic Hierarchy Process (AHP) method was applied to select the weight for each indicator, resulting in 10 most important influencing factors on the selection of the location of educational facilities of the Marine Fisheries Safety Education Facilities: the distribution of marine officers, access to high-speed railways, the number of small ships less than 5 tons, access to highways interchange, the distribution of fishing boats, the close relationship of related industries, the planned new port, the distribution of commercial ports, the number of marine leisure riders, and the availability of long-term land leases in local government councils. The location evaluation index of marine and fishery safety education facilities developed in this study can be used to evaluate each region using national public data, and has the advantage of enabling objective evaluation. Therefore, it is judged that this evaluation index can be used to verify the feasibility of installing marine fisheries safety education facilities as well as other marine-related facilities.