• Korean Journal of Remote Sensing
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• v.39 no.6_2
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• pp.1615-1633
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• 2023

Sargassum horneri is one of the floating algae in the sea, which breeds in large quantities in the Yellow Sea and East China Sea and then flows into the coast of Republic of Korea, causing various problems such as destroying the environment and damaging fish farms. In order to effectively prevent damage and preserve the coastal environment, the development of Sargassum horneri detection algorithms using satellite-based remote sensing technology has been actively developed. However, incorrect detection information causes an increase in the moving distance of ships collecting Sargassum horneri and confusion in the response of related local governments or institutions,so it is very important to minimize false detections when producing Sargassum horneri spatial information. This study applied technology to automatically remove false detection results using the GOCI-II-based Sargassum horneri detection algorithm of the National Ocean Satellite Center (NOSC) of the Korea Hydrographic and Oceanography Agency (KHOA). Based on the results of analyzing the causes of major false detection results, it includes a process of removing linear and sporadic false detections and green algae that occurs in large quantities along the coast of China in spring and summer by considering them as false detections. The technology to automatically remove false detection was applied to the dates when Sargassum horneri occurred from February 24 to June 25, 2022. Visual assessment results were generated using mid-resolution satellite images, qualitative and quantitative evaluations were performed. Linear false detection results were completely removed, and most of the sporadic and green algae false detection results that affected the distribution were removed. Even after the automatic false detection removal process, it was possible to confirm the distribution area of Sargassum horneri compared to the visual assessment results, and the accuracy and precision calculated using the binary classification model averaged 97.73% and 95.4%, respectively. Recall value was very low at 29.03%, which is presumed to be due to the effect of Sargassum horneri movement due to the observation time discrepancy between GOCI-II and mid-resolution satellite images, differences in spatial resolution, location deviation by orthocorrection, and cloud masking. The results of this study's removal of false detections of Sargassum horneri can determine the spatial distribution status in near real-time, but there are limitations in accurately estimating biomass. Therefore, continuous research on upgrading the Sargassum horneri monitoring system must be conducted to use it as data for establishing future Sargassum horneri response plans.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.19 no.5
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• pp.527-536
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• 2018

This study examined the success factors of six sigma innovation in small- and medium-sized venture companies. The findings are summarized as follows. The importance of 20 items in a total of 4 factors showed that corporate vision was number one in the manager's support, followed by program composition, passionate support, high performance guarantee, and quality activity continuity. This suggests that all members can operate the program by the structured system with a sense of united goal under the company-offered vision as a community when the goal, idea or vision of six sigma activities are shared to members of the entire organization. In addition, high success can be achieved when supported by company-wide enthusiasm and high compensation for sharers' innovative efforts of six sigma at the same time. Small- and medium-sized venture companies should develop brisk six sigma activities of advanced precision parts in such an environment that the technology competition is becoming increasingly fierce. The six sigma movement should be developed as a niche strategy for small organizations with united vision sharing by company-wide operational commitment and high self-esteem for the organizational characteristics of small- and medium-sized venture companies run by key minority organizations and members.

• The Journal of the Korea Contents Association
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• v.9 no.3
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• pp.361-371
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• 2009

LAMS(learning activity management system)[1] is one of the useful tools for designing and managing effectively the learning activities such as web search, chat, forum, grouping, and board. Even if LAMS has been upgraded to support the methods for making e-Learning contents conveniently, it does not have a method to communicate with external educational contents (EEC) made by external tools like Flash, Java, Visual C++, and so on. LAMS, which has been operated on Web environment, should manage all EECs like video and dynamic educational contents as educational contents in LAMS database. However, the current LAMS does not support the functionalities which can provide information of EECs to LAMS database and can also access any information about EECs from the database yet. In this paper, we propose the communication mechanism between the LAMS and EECs for solving the problem. In special, the mechanism makes many statistical data by using the information, and provides them for reflecting in education, and can control various learning management that was impossible under the original LAMS. Based on the proposed mechanism, teachers using LAMS can make more various educational contents and can manage them in the system.

• Economic and Environmental Geology
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• v.42 no.4
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• pp.343-356
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• 2009

SCS method was applied to make the assessments of direct runoff according to land use changes in Jeju island. Land uses were obtained from 5 year-period remote sensing time series data from 1975 to 2000 which are provided by Water Management Information System (WAMIS). Hydrologic soil groups were categorized based on soil series of National Academy of Agricultural Sciences (NAAS), and permeable geologic structures such as Sumgol, Gotzawal and so on. The land uses of Jeju island are obviously characterized by urban-agricultural areas increases, and forest areas decrease. According to land use changes, curve number (CN) for Jeju island was consistently increased from 65.3 in 1975 to 69.6 in 2000. From 1975 to 2000, the amount of direct runoff and ratios increased due to CN changes. When the rainfall data in 1995 was applied to each year, the direct runoff amounts were $299.0{\sim}351.6\;mm$, and runoff ratios were $15.1{\sim}17.7%$. In the case of the application of the rainfall data in 2000, the direct runoff amounts were $136.9{\sim}161.5\;mm$, and runoff ratios were $9.7{\sim}11.5%$. Since direct runoff can be closely related to groundwater recharge and sustainable groundwater yield, the groundwater influence caused by land use changes or district exploitations should be considered for the reasonable water management and development in Jeju island.

• Journal of the Institute of Electronics Engineers of Korea TC
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• v.45 no.9
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• pp.39-48
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• 2008

Recently, many multimedia services have emerged in Internet such as real-time and non- real time services. However, in this Internet environment, we have some limitations to satisfy each service feature. To guarantee the service features in Measurement-Based Admission Control(MBAC) based system on the flow-aware network, there is the method applying Dynamic Priority Scheduling(DPS) algorithm that gives a higher priority to an earlier incoming flow in all of the link bandwidth. This paper classifies all flows under several groups according to flow characteristics on per-flow MBAC algorithm based system. In each flow group, DPS algorithm is applied. This paper proposes two methods that are a DPS based bandwidth borrowing method and a bandwidth dynamic allocation method. The former is that if low priority class has available bandwidths, the flow of high priority class borrows the bandwidth of low priority class when high priority flow has insufficient bandwidth to connect a flow call. The later is that the each group has a minimum bandwidth and is allocated the bandwidth dynamically according to the excess rate for available bandwidth. We compare and analyze the characteristics of the two proposed methods through the simulation experiments. As the results of the experiment, the proposed methods are more effective than existing DPS based method on the packet loss and delay characteristics. Consequently the proposed two methods are very useful in various multimedia network environments.

• Journal of the Korea Institute of Building Construction
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• v.22 no.6
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• pp.689-700
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• 2022

Layout work for building structures requires high precision to construct structural elements in the correct location. However, the accuracy and precision of the layout position are affected by the worker's skill, and productivity can be reduced when there is information loss and error. To solve this problem, it is necessary to automate the overall layout operation and introduce information technology, and layout process automation using construction robots can be an effective means of doing this. This study develops a prototype of an automated layout robot for building structures and evaluates its basic performance. The developed robot is largely composed of driving, marking, sensing, and control units, and is designed to enable various driving methods, and movement and rotation of the marking unit in consideration of the environment on structural work. The driving and marking performance experiments showed satisfactory performance in terms of driving distance error and marking quality, while the need for improvement in terms of some driving methods and marking precision was confirmed. Based on the results of this study, we intend to continuously improve the robot's performance and establish an automation system for overall layout work process.

• Journal of Intelligence and Information Systems
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• v.24 no.3
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• pp.67-88
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• 2018

Until recently, as we recognize the significance of sustainable growth and competitiveness of small-and-medium sized enterprises (SMEs), governmental support for tangible resources such as R&D, manpower, funds, etc. has been mainly provided. However, it is also true that the inefficiency of support systems such as underestimated or redundant support has been raised because there exist conflicting policies in terms of appropriateness, effectiveness and efficiency of business support. From the perspective of the government or a company, we believe that due to limited resources of SMEs technology development and capacity enhancement through collaboration with external sources is the basis for creating competitive advantage for companies, and also emphasize value creation activities for it. This is why value chain network analysis is necessary in order to analyze inter-company deal relationships from a series of value chains and visualize results through establishing knowledge ecosystems at the corporate level. There exist Technology Opportunity Discovery (TOD) system that provides information on relevant products or technology status of companies with patents through retrievals over patent, product, or company name, CRETOP and KISLINE which both allow to view company (financial) information and credit information, but there exists no online system that provides a list of similar (competitive) companies based on the analysis of value chain network or information on potential clients or demanders that can have business deals in future. Therefore, we focus on the "Value Chain Network System (VCNS)", a support partner for planning the corporate business strategy developed and managed by KISTI, and investigate the types of embedded network-based analysis modules, databases (D/Bs) to support them, and how to utilize the system efficiently. Further we explore the function of network visualization in intelligent value chain analysis system which becomes the core information to understand industrial structure ystem and to develop a company's new product development. In order for a company to have the competitive superiority over other companies, it is necessary to identify who are the competitors with patents or products currently being produced, and searching for similar companies or competitors by each type of industry is the key to securing competitiveness in the commercialization of the target company. In addition, transaction information, which becomes business activity between companies, plays an important role in providing information regarding potential customers when both parties enter similar fields together. Identifying a competitor at the enterprise or industry level by using a network map based on such inter-company sales information can be implemented as a core module of value chain analysis. The Value Chain Network System (VCNS) combines the concepts of value chain and industrial structure analysis with corporate information simply collected to date, so that it can grasp not only the market competition situation of individual companies but also the value chain relationship of a specific industry. Especially, it can be useful as an information analysis tool at the corporate level such as identification of industry structure, identification of competitor trends, analysis of competitors, locating suppliers (sellers) and demanders (buyers), industry trends by item, finding promising items, finding new entrants, finding core companies and items by value chain, and recognizing the patents with corresponding companies, etc. In addition, based on the objectivity and reliability of the analysis results from transaction deals information and financial data, it is expected that value chain network system will be utilized for various purposes such as information support for business evaluation, R&D decision support and mid-term or short-term demand forecasting, in particular to more than 15,000 member companies in Korea, employees in R&D service sectors government-funded research institutes and public organizations. In order to strengthen business competitiveness of companies, technology, patent and market information have been provided so far mainly by government agencies and private research-and-development service companies. This service has been presented in frames of patent analysis (mainly for rating, quantitative analysis) or market analysis (for market prediction and demand forecasting based on market reports). However, there was a limitation to solving the lack of information, which is one of the difficulties that firms in Korea often face in the stage of commercialization. In particular, it is much more difficult to obtain information about competitors and potential candidates. In this study, the real-time value chain analysis and visualization service module based on the proposed network map and the data in hands is compared with the expected market share, estimated sales volume, contact information (which implies potential suppliers for raw material / parts, and potential demanders for complete products / modules). In future research, we intend to carry out the in-depth research for further investigating the indices of competitive factors through participation of research subjects and newly developing competitive indices for competitors or substitute items, and to additively promoting with data mining techniques and algorithms for improving the performance of VCNS.

• Korean Journal of Remote Sensing
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• v.39 no.5_1
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• pp.669-681
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• 2023

Studies have tried to apply remote sensing technology, a non-destructive survey method, instead of the existing destructive survey, which requires relatively large labor input and a long time to estimate chlorophyll content, which is an important indicator for evaluating the growth of fruit trees. This study was conducted to non-destructively evaluate the chlorophyll content of pear tree leaves using unmanned aerial vehicle-based hyperspectral imagery for two years(2021, 2022). The reflectance of the single bands of the pear tree canopy extracted through image processing was band rationed to minimize unstable radiation effects depending on time changes. The estimation (calibration and validation) models were developed using machine learning algorithms of elastic-net, k-nearest neighbors(KNN), and support vector machine with band ratios as input variables. By comparing the performance of estimation models based on full band ratios, key band ratios that are advantageous for reducing computational costs and improving reproducibility were selected. As a result, for all machine learning models, when calibration of coefficient of determination (R²)≥0.67, root mean squared error (RMSE)≤1.22 ㎍/cm², relative error (RE)≤17.9% and validation of R²≥0.56, RMSE≤1.41 ㎍/cm², RE≤20.7% using full band ratios were compared, four key band ratios were selected. There was relatively no significant difference in validation performance between machine learning models. Therefore, the KNN model with the highest calibration performance was used as the standard, and its key band ratios were 710/714, 718/722, 754/758, and 758/762 nm. The performance of calibration showed R²=0.80, RMSE=0.94 ㎍/cm², RE=13.9%, and validation showed R²=0.57, RMSE=1.40 ㎍/cm², RE=20.5%. Although the performance results based on validation were not sufficient to estimate the chlorophyll content of pear tree leaves, it is meaningful that key band ratios were selected as a standard for future research. To improve estimation performance, it is necessary to continuously secure additional datasets and improve the estimation model by reproducing it in actual orchards. In future research, it is necessary to continuously secure additional datasets to improve estimation performance, verify the reliability of the selected key band ratios, and upgrade the estimation model to be reproducible in actual orchards.

• Korean Journal of Agricultural and Forest Meteorology
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• v.19 no.3
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• pp.153-163
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• 2017

The objective of this study is to enhance the model's speed of estimating weather variables (e.g., minimum/maximum temperature, sunshine hour, PRISM (Parameter-elevation Regression on Independent Slopes Model) based precipitation), which are applied to the Agrometeorological Early Warning System (http://www.agmet.kr). The current process of weather estimation is operated on high-performance multi-core CPUs that have 8 physical cores and 16 logical threads. Nonetheless, the server is not even dedicated to the handling of a single county, indicating that very high overhead is involved in calculating the 10 counties of the Seomjin River Basin. In order to reduce such overhead, several cache and parallelization techniques were used to measure the performance and to check the applicability. Results are as follows: (1) for simple calculations such as Growing Degree Days accumulation, the time required for Input and Output (I/O) is significantly greater than that for calculation, suggesting the need of a technique which reduces disk I/O bottlenecks; (2) when there are many I/O, it is advantageous to distribute them on several servers. However, each server must have a cache for input data so that it does not compete for the same resource; and (3) GPU-based parallel processing method is most suitable for models such as PRISM with large computation loads.

• Journal of Appropriate Technology
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• v.6 no.2
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• pp.174-182
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• 2020

The permissible limit of ammonia concentration in drinking water recommended by the World Health Organization (WHO) is 1.5 mg/L. However, in the case of groundwater in Kathmandu, Nepal, the concentration of ammonia fluctuates dramatically from 0 to 120 mg/L at different locations and groundwater depths (Chapagain et al., 2010). Such a high concentration of ammonia causes aesthetic problems in drinking water, such as bad taste and odor; hence, prior treatment is required. In Kathmandu, half of the population utilizes groundwater, which is also employed for drinking water, but owing to a lack of knowledge of household water filters, residents of Kathmandu tend to depend greatly on commercially available jar water than on the installation of a proper household filtration method. Thus, in our study, we employed adsorption and reverse osmosis (RO) as two of the most viable decentralized/household treatment options to address the issue of high contamination of ammonia in drinking water. We evaluated their performances from technical and the economic perspectives using synthetically prepared groundwater at varying ammonia concentrations (50 mg/L and 15 mg/L). Consequently, it was found that adsorption via ion exchange (IE) resin was a comparatively better ammonia removal technology than RO, with 100% ammonia removal even after regeneration; the removal by RO was limited to up to 90%. Furthermore, our study suggests that IE is the most suitable ammonia removal technology for places with lower water consumption (< 50 L/day), whereas RO seemed to be a cost-effective technology for places with higher water consumption, where the daily water demand exceeds 50 L/day. Lastly, these assessments suggest that installing a suitable household treatment system would be more efficient and sustainable from both technical and economic points of view than purchasing commercially bottled water.