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Extraction of Water Depth in Coastal Area Using EO-1 Hyperion Imagery (EO-1 Hyperion 영상을 이용한 연안해역의 수심 추출)

  • Seo, Dong-Ju;Kim, Jin-Soo
    • Journal of the Korea Institute of Information and Communication Engineering
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    • v.12 no.4
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    • pp.716-723
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    • 2008
  • With rapid development of science and technology and recent widening of mankind's range of activities, development of coastal waters and the environment have emerged as global issues. In relation to this, to allow more extensive analyses, the use of satellite images has been on the increase. This study aims at utilizing hyperspectral satellite images in determining the depth of coastal waters more efficiently. For this purpose, a partial image of the research subject was first extracted from an EO-1 Hyperion satellite image, and atmospheric and geometric corrections were made. Minimum noise fraction (MNF) transformation was then performed to compress the bands, and the band most suitable for analyzing the characteristics of the water body was selected. Within the chosen band, the diffuse attenuation coefficient Kd was determined. By deciding the end-member of pixels with pure spectral properties and conducting mapping based on the linear spectral unmixing method, the depth of water at the coastal area in question was ultimately determined. The research findings showed the calculated depth of water differed by an average of 1.2 m from that given on the digital sea map; the errors grew larger when the water to be measured was deeper. If accuracy in atmospheric correction, end-member determination, and Kd calculation is enhanced in the future, it will likely be possible to determine water depths more economically and efficiently.

Comparison among Gamma(${\gamma}$) Line Systems for Non-Linear Gamma Curve (비선형 감마 커브를 위한 감마 라인 시스템의 비교)

  • Jang, Won-Woo;Lee, Sung-Mok;Ha, Joo-Young;Kim, Joo-Hyun;Kim, Sang-Choon;Kang, Bong-Soon
    • Journal of the Korea Institute of Information and Communication Engineering
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    • v.11 no.2
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    • pp.265-272
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    • 2007
  • This proposed gamma (${\gamma}$) correction system is developed to reduce the difference between non-linear gamma curve produced by a typical formula and result produced by the proposed algorithm. In order to reduce the difference, the proposed system is using the Least Squares Polynomial which is calculating the best fitting polynomial through a set of points which is sampled. Each system is consisting of continuous several kinds of equations and having their own overlap sections to get more precise. Based on the algorithm verified by MATLAB, the proposed systems are implemented by using Verilog-HDL. This paper will compare the previous algorithm of gamma system such as Existing system with Seed Table with the latest that such as Proposed system. The former and the latter system have 1, 2 clock latency; each 1 result per clock. Because each of the error range (LSB) is $1{\sim}+1,\;0{\sim}+36$, we can how that Proposed system is improved. Under the condition of SAMSUNG STD90 0.35 worst case, each gate count is 2,063, 2,564 gates and each maximum data arrival time is 29.05[ns], 17.52[ns], respectively.

A Study on Smart Ground Resistance Measurement Technology Based on Aduino (아두이노 기반 IT융합 스마트 대지저항 측정 기술 연구)

  • Kim, Hong Yong
    • Journal of the Society of Disaster Information
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    • v.17 no.4
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    • pp.684-693
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    • 2021
  • Purpose: The purpose is to establish a safe facility environment from abnormal voltages such as lightning by developing a smart land resistance measuring device that can acquire real-time land resistance data using Arduino. Method: This paper studied design models and application cases by developing a land resistance acquisition and analysis system with Arduino and a power line communication (PLC) system. Some sites in the wind power generation complex in Gyeongsangnam-do were selected as test beds, and real-time land resistance data applied with new technologies were obtained. The electrode arrangement adopted a smart electrode arrangement using a combination of a Wenner four electrode arrangement and a Schlumberger electrode arrangement. Result: First, the characteristic of this technology is that the depth of smart multi-electrodes is organized differently to reduce the error range of the acquired data even in the stratigraphic structure with specificity between floors. Second, IT convergence technology was applied to enable real-time transmission and reception of information on land resistance data acquired from smart ground electrodes through the Internet of Things. Finally, it is possible to establish a regular management system and analyze big data accumulated in the server to check the trend of changes in various elements, and to model the optimal ground algorithm and ground system design for the IT convergence environment. Conclusion: This technology will reduce surge damage caused by lightning on urban infrastructure underlying the 4th industrial era and design an optimized ground system model to protect the safety and life of users. It is also expected to secure intellectual property rights of pure domestic technology to create jobs and revitalize our industry, which has been stagnant as a pandemic in the post-COVID-19 era.

A Study on the Analysis of Miles Training Effect (마일즈 훈련효과 분석에 관한 연구)

  • Lee, Yong-Yeon;Lee, Ho Jun;Kim, Yong-Pil
    • Journal of the Korea Academia-Industrial cooperation Society
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    • v.22 no.4
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    • pp.353-359
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    • 2021
  • The Army is constructing a training system using Miles equipment that applies the latest science and technology to carry out military training. The Miles training system is a system that uses Miles equipment to simulate the damage situation of combat personnel and equipment in the same way as an actual battlefield by conducting practiced maneuvers in the field. Through this, the training force can experience conditions similar to an actual battle. In particular, the training effects of the warriors participating in the training can be maximized by establishing an integrated system that utilizes cutting-edge science technologies, such as information communication and computer simulation. This study analyzed the effects of Miles training in the army using scientific techniques targeted at the mid-range Miles. In particular, the effect index for analyzing the training effect was derived from a literature survey and expert opinions. The weight of each effect index was calculated by applying the Swing method. The final training effect was calculated by combining the results of the survey from train-experienced people. The Miles training effect was 2.6 times more effective than previous training without using Miles, and the satisfaction rate with Miles training according to status was high through variance analysis, and the difference was statistically significant.

Intelligent Smart Farm A Study on Productivity: Focused on Tomato farm Households (지능형 스마트 팜 활용과 생산성에 관한 연구: 토마토 농가 사례를 중심으로)

  • Lee, Jae Kyung;Seol, Byung Moon
    • Asia-Pacific Journal of Business Venturing and Entrepreneurship
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    • v.14 no.3
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    • pp.185-199
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    • 2019
  • Korea's facility horticulture has developed remarkably in a short period of time. However, in order to secure international competitiveness in response to unfavorable surrounding conditions such as high operating costs and market opening, it is necessary to diagnose the problems of facility horticulture and prepare countermeasures through analysis. The purpose of this study was to analyze the case of leading farmers by introducing information and communication technology (ICT) in hydroponic cultivation agriculture and horticulture, and to examine how agricultural technology utilizing smart farm and big data of facility horticulture contribute to farm productivity. Crop growth information gathering and analysis solutions were developed to analyze the productivity change factors calculated from hydroponics tomato farms and strawberry farms. The results of this study are as follows. The application range of the leaf temperature was verified to be variously utilized such as house ventilation in the facility, opening and closing of the insulation curtain, and determination of the initial watering point and the ending time point. Second, it is necessary to utilize water content information of crop growth. It was confirmed that the crop growth rate information can confirm whether the present state of crops is nutrition or reproduction, and can control the water content artificially according to photosynthesis ability. Third, utilize EC and pH information of crops. Depending on the crop, EC values should be different according to climatic conditions. It was confirmed that the current state of the crops can be confirmed by comparing EC and pH, which are measured from the supplied EC, pH and draining. Based on the results of this study, it can be confirmed that the productivity of smart farm can be affected by how to use the information of measurement growth.

Wall Cuckoo: A Method for Reducing Memory Access Using Hash Function Categorization (월 쿠쿠: 해시 함수 분류를 이용한 메모리 접근 감소 방법)

  • Moon, Seong-kwang;Min, Dae-hong;Jang, Rhong-ho;Jung, Chang-hun;NYang, Dae-hun;Lee, Kyung-hee
    • KIPS Transactions on Computer and Communication Systems
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    • v.8 no.6
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    • pp.127-138
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    • 2019
  • The data response speed is a critical issue of cloud services because it directly related to the user experience. As such, the in-memory database is widely adopted in many cloud-based applications for achieving fast data response. However, the current implementation of the in-memory database is mostly based on the linked list-based hash table which cannot guarantee the constant data response time. Thus, cuckoo hashing was introduced as an alternative solution, however, there is a disadvantage that only half of the allocated memory can be used for storing data. Subsequently, bucketized cuckoo hashing (BCH) improved the performance of cuckoo hashing in terms of memory efficiency but still cannot overcome the limitation that the insert overhead. In this paper, we propose a data management solution called Wall Cuckoo which aims to improve not only the insert performance but also lookup performance of BCH. The key idea of Wall Cuckoo is that separates the data among a bucket according to the different hash function be used. By doing so, the searching range among the bucket is narrowed down, thereby the amount of slot accesses required for the data lookup can be reduced. At the same time, the insert performance will be improved because the insert is following up the operation of the lookup. According to analysis, the expected value of slot access required for our Wall Cuckoo is less than that of BCH. We conducted experiments to show that Wall Cuckoo outperforms the BCH and Sorting Cuckoo in terms of the amount of slot access in lookup and insert operations and in different load factor (i.e., 10%-95%).

Feasibility Study on Integration of SSR Correction into Network RTK to Provide More Robust Service

  • Lim, Cheol-Soon;Park, Byungwoon;Kim, Dong-Uk;Kee, Chang-Don;Park, Kwan-Dong;Seo, Seungwoo;So, Hyoungmin;Park, Junpyo
    • Journal of Positioning, Navigation, and Timing
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    • v.7 no.4
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    • pp.295-305
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    • 2018
  • Network RTK is a highly practical technology that can provide high positioning accuracy at levels between cm~dm regardless of user location in the network by extending the available range of RTK using reference station network. In particular, unlike other carrier-based positioning techniques such as PPP, users are able to acquire high-accuracy positions within a short initialization time of a few or tens of seconds, which increases its value as a future navigation system. However, corrections must be continuously received to maintain a high level of positioning accuracy, and when a time delay of more than 30 seconds occurs, the accuracy may be reduced to the code-based positioning level of meters. In case of SSR, which is currently in the process of standardization for PPP service, the corrections by each error source are transmitted in different transmission intervals, and the rate of change of each correction is transmitted together to compensate the time delay. Using these features of SSR correction is expected to reduce the performance degradation even if users do not receive the network RTK corrections for more than 30 seconds. In this paper, the simulation data were generated from 5 domestic reference stations in Gunwi, Yeongdoek, Daegu, Gimcheon, and Yecheon, and the network RTK and SSR corrections were generated for the corresponding data and applied to the simulation data from Cheongsong reference station, assumed as the user. As a result of the experiment assuming 30 seconds of missing data, the positioning performance compensating for time delay by SSR was analyzed to be horizontal RMS (about 5 cm) and vertical RMS (about 8 cm), and the 95% error was 8.7 cm horizontal and 1cm vertical. This is a significant amount when compared to the horizontal and vertical RMS of 0.3 cm and 0.6 cm, respectively, for Network RTK without time delay for the same data, but is considerably smaller compared to the 0.5 ~ 1 m accuracy level of DGPS or SBAS. Therefore, maintaining Network RTK mode using SSR rather than switching to code-based DGPS or SBAS mode due to failure to receive the network RTK corrections for 30 seconds is considered to be favorable in terms of maintaining position accuracy and recovering performance by quickly resolving the integer ambiguity when the communication channel is recovered.

A Study on the Practical Methodology of Engineering Education through Multi-account Service Composition with Enhanced User Security (사용자 보안을 강화한 다중 계정 서비스 구성을 통해 이루어진 공학 교육 실천 방법론에 관한 연구)

  • Kang, Kyoung-Bo;Park, Jea-Soon;Chang, Eun-Young
    • Journal of Practical Engineering Education
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    • v.10 no.1
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    • pp.1-7
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    • 2018
  • The dual security system that manages user's account information and uses NFC and OTP has been proposed. It also enhances the security of the user authentication phase by using the features that recognize within the range of less than 1m of NFC and the high security of NFC itself. During the graduation work design process which was carried out for one year and six months in a group of two in the electronics engineering major of the four-year undergraduate system was conducted. In the interim results, we participated in the conferences and thesis contest at the Institute of related to major for three times. Finally passed the examination process for three times judged by 6 professors in the major. The results were published in a graduation thesis together with other people who passed and composed in thesis form. Through the experience gained through these stages of design and production, it has gained the confidence to gain employment opportunities and actively pursue the growth stage, and presented a methodology to practice engineering education through employment.

A Study on the Improvement of Skin Loss Area in Skin Color Extraction for Face Detection (얼굴 검출을 위한 피부색 추출 과정에서 피부색 손실 영역 개선에 관한 연구)

  • Kim, Dong In;Lee, Gang Seong;Han, Kun Hee;Lee, Sang Hun
    • Journal of the Korea Convergence Society
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    • v.10 no.5
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    • pp.1-8
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    • 2019
  • In this paper, we propose an improved facial skin color extraction method to solve the problem that facial surface is lost due to shadow or illumination in skin color extraction process and skin color extraction is not possible. In the conventional HSV method, when facial surface is brightly illuminated by light, the skin color component is lost in the skin color extraction process, so that a loss area appears on the face surface. In order to solve these problems, we extract the skin color, determine the elements in the H channel value range of the skin color in the HSV color space among the lost skin elements, and combine the coordinates of the lost part with the coordinates of the original image, To minimize the number of In the face detection process, the face was detected using the LBP Cascade Classifier, which represents texture feature information in the extracted skin color image. Experimental results show that the proposed method improves the detection rate and accuracy by 5.8% and 9.6%, respectively, compared with conventional RGB and HSV skin color extraction and face detection using the LBP cascade classifier method.

Analysis on the Aspect of Learners' Explorations Reflected in High School Informatics Textbooks Based on the 2015 Revised National Curriculum (2015 개정 교육과정에 근거한 고등학교 정보 교과서의 탐구성 분석)

  • Kang, Oh-Han
    • KIPS Transactions on Computer and Communication Systems
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    • v.8 no.5
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    • pp.103-110
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    • 2019
  • In this research, one common chapter, Problem Solving and Programming, in seven different types of high school informatics textbooks was analyzed in terms of the aspect of learners' explorations. These textbooks were newly developed based on the 2015 revised national curriculum. Romey's analysis was used to the textbooks along with four analytic elements: texts, data, activities, and evaluation. The study results showed that the textbooks can highly encourage learners' further explorations according to the four analytic elements reflected in the seven textbooks: one out of the six textbooks well designed for texts, three for data, six for activities, two for evaluation. In terms of Romey's involvement index points, six of the seven textbooks had low indexes of texts, ranging from 0.175 to 0.393. Data indexes were extremely low in four out of the seven textbooks, ranging from 0.058 to 0.226. Five out of the seven textbooks had very high indexes of evaluation in the broad range of 2 to 6.333 points. Furthermore, these newly designed textbooks can more greatly facilitate students' explorations than previously existing textbooks in three elements: texts, data, and activities. Evaluation indexes significantly increased in these new textbooks from 0.916 to 3.914, which had excessive points in terms of promoting students' explorations. Further methods to improve the textbook quality is proposed based on the results from this analysis.