• Title/Summary/Keyword: Field correction

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Constraints and opportunities to sustain future wheat yield and water productivity in semi-arid environment

  • Ahmad, Mirza Junaid;Choi, Kyung-Sook
    • Proceedings of the Korea Water Resources Association Conference
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    • 2019.05a
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    • pp.185-185
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    • 2019
  • Sustaining future wheat production is challenged by anthropogenically forced climate warming and drying led by increased concentration of greenhouse gases all around the globe. Warming stresses, originating from the elevated $CO_2$ concentration, are continuously reported to have negative impacts on wheat growth and yield. Yet, elevated $CO_2$ concentration, despite being disparagingly blamed for promoting warming, is also associated with a phenomenon called $CO_2$ enrichment; in which wheat yield can improve due to the enhanced photosynthesis rates and less water loss through transpiration. The conflicting nature of climate warming and $CO_2$ enrichment and their interplay can have specific implications under different environments. It is established form the field and simulation studies that the two contrasting phenomena would act severely in their own respect under arid and semi-arid environments. Wheat is a dietary staple for masses in Pakistan. The country's wheat production system is under constant stress to produce more from irrigated agricultural lands, primarily lying under arid to semi-arid environments, to meet the rapidly growing domestic needs. This work comprehensively examines the warming impacts over wheat yield and water productivity (WP), with and without the inclusion of $CO_2$ enrichment, under semi-arid environment of Punjab which is the largest agricultural province of Pakistan. Future wheat yields and WPs were simulated by FAO developed AquaCrop model v 5.0. The model was run using the bias-correction climate change projections up to 2080 under two representative concentration pathways (RCP) scenarios: 4.5 and 8.5. Wheat yield and WPs decreased without considering the $CO_2$ enrichment effects owing to the elevated irrigation demands and accelerated evapotranspiration rates. The results suggested that $CO_2$ enrichment could help maintain the current yield and WPs levels during the 2030s (2021-2050); however, it might not withhold the negative climate warming impacts during the 2060s (2051-2080). Furthermore, 10 - 20 day backward shift in sowing dates could also help ease the constraints imposed by climate warming over wheat yields and WPs. Although, $CO_2$ enrichment showed promises to counteract the adverse climate warming impacts but the interactions between climate warming and $CO_2$ concentrations were quite uncertain and required further examination.

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Model-Based Approach to Flight Test System Development to Cope with Demand for Simultaneous Guided Missile Flight Tests (동시다발적인 유도무기 비행시험 수요에 대응하기 위한 모델기반 비행시험 시스템 개발)

  • Park, Woong;Lee, Jae-Chon
    • Journal of the Korea Academia-Industrial cooperation Society
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    • v.20 no.1
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    • pp.268-277
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    • 2019
  • Flight test systems should monitor various conditions in real time during flight tests and take safety measures in an emergency. The importance of ensuring test safety increases in more complicated and wider test environments. Also, due to the transition of wartime operational authority, many guided missile systems must be developed simultaneously. Early deployment and budget reduction by shortening the development and T&E periods are also necessary. Consequently, the risk of flight tests under the circumstance of inefficient test resources is increasing. To address this deficiency, a flight test system model using SysML was proposed in this study. The method of designing and verifying the test system is based on the agile shift left testing methodology of advanced T&E labs and utilizing a system reference model in the aerospace field. Through modeling and simulation analysis, early identification and correction of faults resulting from inconsistent test requirements can mitigate the risk of delays during the T&E phase of flight tests. Also, because the flight test system model was constructed using SysML, it can be applied to test various guided missile systems.

Correction Algorithm of Errors by Seagrasses in Coastal Bathymetry Surveying Using Drone and HD Camera (드론과 HD 카메라를 이용한 수심측량시 잘피에 의한 오차제거 알고리즘)

  • Kim, Gyeongyeop;Choi, Gunhwan;Ahn, Kyungmo
    • Journal of Korean Society of Coastal and Ocean Engineers
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    • v.32 no.6
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    • pp.553-560
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    • 2020
  • This paper presents an algorithm for identifying and eliminating errors by seagrasses in coastal bathymetry surveying using drone and HD camera. Survey errors due to seagrasses were identified, segmentated and eliminated using a L∗a∗b color space model. Bathymetry survey using a drone and HD camera has many advantages over conventional survey methods such as ship-board acoustic sounder or manual level survey which are time consuming and expensive. However, errors caused by sea bed reflectance due to seagrasses habitat hamper the development of new surveying tool. Seagrasses are the flowering plants which start to grow in November and flourish to maximum density until April in Korea. We developed a new algorithm for identifying seagrasses habitat locations and eliminating errors due to seagrasses to get the accurate depth survey data. We tested our algorithm at Wolpo beach. Bathymetry survey data which were obtained using a drone with HD camera and calibrated to eliminate errors due to seagrasses, were compared with depth survey data obtained using ship-board multi-beam acoustic sounder. The abnormal bathymetry data which are defined as the excess of 1.5 times of a standard deviation of random errors, are composed of 8.6% of the test site of area of 200 m by 300 m. By applying the developed algorithm, 92% of abnnormal bathymetry data were successfully eliminated and 33% of RMS errors were reduced.

A Study on Improving the Efficiency of Facility Safety Inspection Work Using Images (영상을 활용한 시설물 안전점검 작업 효율성 향상 방안 연구)

  • Jeon, Kyungsik;Kim, Jintae;Lee, Byoungkil
    • Journal of the Korean Society of Surveying, Geodesy, Photogrammetry and Cartography
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    • v.39 no.3
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    • pp.179-186
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    • 2021
  • In general, the daily safety inspection activities, which investigate damages in structures and measures the size of the damage, have been relied heavily on the visual inspection so far. Since the probe of the condition and performance of facilities by such personnel is often dependent on the subjective judgment of the investigator, the consistency and repeatability of the probing results may reduce. Particularly, damage located in a difficult-to-reach place depends mainly on experience with the naked eye, and an unsafe method using a ladder has mainly applied when necessary. Therefore, in this study, we tried to propose a way of using images that can reduce the deviation between safety inspection investigators, enhance objectivity, and improve the safety of workers. In this study, we have applied homographic transformation as a method of correcting the image. As a result of analyzing the size of the damage in the corrected image of the test subject, it confirms that the accuracy of measuring the magnitude of the damage can satisfy the target levels of 5.0mm and 0.005m2, the target accuracy levels. As a result of the field verification test to which the proposed image correction technique applied, the coefficient of variation of the crack length in the structure decreased from 5.4~7.0% to 0.072~0.12%, and that of the damaged area from 10.9% to 1.6%. It confirms that the measurement accuracy is improved. Therefore, it is expected that this study on the image utilization technique in safety inspection activities can increase the accuracy of damage measurement and improve the reliability of the safety inspection reports and exterior survey drawings.

The Mediating Effect of Social Support on Academic Stress of Nursing Students and Adjustment to College Life (간호대학생의 학업스트레스와 대학생활적응 : 사회적지지의 매개효과)

  • Seo, MyeongJa;Oh, Jinjoo
    • The Journal of the Korea Contents Association
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    • v.21 no.4
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    • pp.815-824
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    • 2021
  • Purpose: This study was to identify the degree of academic stress, college life Adjustment, and social support perceived by nursing students, and to identify the mediating effect of social support between academic stress and college life Adjustment. The participants were 248 nursing college students who have experience in field practice at 4 universities in G metropolitan city. Data analysis was analyzed using SPSS 24.0 as Descriptive statistics, Independent-test, One-way ANOVA, Pearson's correction, and Bootstrapping. Results: The study found 2.68 points for academic stress, 4.11 points for social support, and 3.5 points for college life adjustment. Academic stress was negative correlation with social support and Adjustment to college life, social support was positive correlation with Adjustment to college life. As a result of the analysis by applying the mediating effect verification model 4, first, academic stress had a significant negative effect on social support, second, academic stress had a negative effect on college life adjustment, and social support had a positive effect on college life adjustment. Third, the analysis of the total, direct, and indirect effects of academic stress and social support on college life adjustment showed that they were all significant. In conclusion, it has been found that social support has a partially controlled mediating effect between academic stress and college life adjustment.

A Study of VR Interaction for Non-contact Hair Styling (비대면 헤어 스타일링 재현을 위한 VR 인터렉션 연구)

  • Park, Sungjun;Yoo, Sangwook;Chin, Seongah
    • The Journal of the Convergence on Culture Technology
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    • v.8 no.2
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    • pp.367-372
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    • 2022
  • With the recent advent of the New Normal era, realistic technologies and non-contact technologies are receiving social attention. However, the hair styling field focuses on the direction of the hair itself, individual movements, and modeling, focusing on hair simulation. In order to create an improved practice environment and demand of the times, this study proposed a non-contact hair styling VR system. In the theoretical review, we studied the existing cases of hair cut research. Existing haircut-related research tend to be mainly focused on force-based feedback. Research on the interactive haircut work in the virtual environment as addressed in this paper has not been done yet. VR controllers capable of finger tracking the movements necessary for beauty enable selection, cutting, and rotation of beauty tools, and built a non-contact collaboration environment. As a result, we conducted two experiments for interactive hair cutting in VR. First, it is a haircut operation for synchronization using finger tracking and holding hook animation. We made position correction for accurate motion. Second, it is a real-time interactive cutting operation in a multi-user virtual collaboration environment. This made it possible for instructors and learners to communicate with each other through VR HMD built-in microphones and Photon Voice in non-contact situations.

Soil Depth Estimation and Prediction Model Correction for Mountain Slopes Using a Seismic Survey (탄성파 탐사를 활용한 산지사면 토심 추정 및 예측모델 보정)

  • Taeho Bong;Sangjun Im;Jung Il Seo;Dongyeob Kim;Joon Heo
    • Journal of Korean Society of Forest Science
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    • v.112 no.3
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    • pp.340-351
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    • 2023
  • Landslides are major natural geological hazards that cause enormous property damage and human casualties annually. The vulnerability of mountainous areas to landslides is further exacerbated by the impacts of climate change. Soil depth is a crucial parameter in landslide and debris flow analysis, and plays an important role in the evaluation of watershed hydrological processes that affect slope stability. An accurate method of estimating soil depth is to directly investigate the soil strata in the field. However, this requires significant amounts of time and money; thus, numerous models for predicting soil depth have been proposed. However, they still have limitations in terms of practicality and accuracy. In this study, 71 seismic survey results were collected from domestic mountainous areas to estimate soil depth on hill slopes. Soil depth was estimated on the basis of a shear wave velocity of 700 m/s, and a database was established for slope angle, elevation, and soil depth. Consequently, the statistical characteristics of soil depth were analyzed, and the correlations between slope angle and soil depth, and between elevation and soil depth were investigated. Moreover, various soil depth prediction models based on slope angle were investigated, and corrected linear and exponential soil depth prediction models were proposed.

Prospect of Sustainable Organic Tea Farming in Lwang, Kaski, Nepa (네팔 르왕지역의 지속적 유기농차 재배 방향)

  • Chang, K.J.;Huang, D.S.;Park, C.H.;Jeon, U.S.;Jeon, S.H.;Binod, Basnet.
    • Journal of Practical Agriculture & Fisheries Research
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    • v.12 no.1
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    • pp.137-150
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    • 2010
  • Traditionally, like many people in mountain region of the Himalaya, the Lwang communities depend on mix of subsistence agriculture, animal husbandry, and seasonal migrant labor for their livelihoods. These traditional systems are characterized by low productivity, diverse use of available natural resources (largely for home consumption), limited markets, and some aversion for innovation. The potential to generate wealth through commerce has largely been untapped by these mountain residents and thus is undervalued in local and national economies. Introduction of organic tea farming is a part of Lwang community's several initiatives to break the vicious poverty cycle Annapurna Conservation Area Project (ACAP) played facilitating roles in all their efforts since beginning. In five years, the tea plantation emerged as a new means for secured a livelihood. This study aims to analyze the current practices in tea farming both in terms of farm management and soil nutrient status(technical) and the prosperity of the tea farmers (social). The technical aspect covers the soil and tea leaf analysis of various nutrients contents in the soil and tea leaf. Originally, the technical aspect of the study was not planned but later during the consultation with the advisor it was taken into consideration which added value to the research study. The sample were collected from different locations and analyzed on the field itself. The other part of the study i.e. the social aspect was done through questionnaire survey and focus group discussion. the tea farming provided them not only a new opportunity but also earned an identity in the region. This initiative was undertaken as a piloting measure. Now that the tea is in production with processing unit established locally, more serious consideration has to be given for better yield and economic prosperity. This research finding will help the community to analyze their efforts and make correction measures in tea garden management and application of fertilizer. It is also expected to fill up the gaps of knowledge and information required to reduce economic stresses and enhance capacity of farmers to make the tea farming a sustainable and beneficial business. The findings are expected to Sustainability of organic tea farming has direct impacts on biodiversity conservation compared to the other traditional farming practices that are more resource intensive. The study will also contribute to identify key action points required for reducing poverty while conserving environment and enhancing livelihoods

The Development of Nutrition Education Program for Improvement of body Perception of Middle School Girls (II);Development of Nutrition Education Program (여중생의 체형인식 개선을 위한 영양교육 프로그램 개발(II);여중생 대상 영양교육 프로그램 개발)

  • Soh, Hye-Kyung;Lee, Eun-Ju;Choi, Bong-Soon
    • Journal of the Korean Society of Food Culture
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    • v.23 no.1
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    • pp.130-137
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    • 2008
  • If we may practice the nutrition education planned on the basis which carefully grasped the inappropriate behavioral determinants of middle-school students, it might be an effective method achieving the change in perception and behavior improving the distorted perception about the ideal body shape, so we are to suggest the 8 week program of body shape perception improvement for successful nutrition education as follows. The body shape perception improvement program is a step-by-step group consulting program. At the introduction stage, we let them understand the meaning of true beauty and body change of teenage period and forming of sexual identity. At the stage of perception conversion, we let them have the opportunity to observe the status of body perception of the teenager and self-observation. At the stage of correction, we let them criticize the distorted body image in the society with mass media at the same time with the self-reflection. At the stage of maintenance and evaluation, we suggested the behavior guidance while preparing it. Setting this as the basis, we applied the contents such as the evaluations through cultural sharing events making somethings while directly participating. As the target groups to practice education were middle school students, we considered the learning level and behavioral features of the middle school students, and composed the programs including the methods such as role play, watching real things, media production, discussions and experiences. If the program of body shape perception improvement developed at this study could be utilized at the field of schools, the teenagers can change their ways of thought naturally avoiding the view about unified appearance rightly perceiving negative self-image that the teenagers can have and if the group consulting can be practiced regularly at each school, many students may experience the change in perception, so it might solicit the improvement of health of the families and local societies as well as that of the individual student.

Plant Species Richness in Korea Utilizing Integrated Biological Survey Data (생물기초조사 통합자료를 활용한 우리나라 식물종 풍부도 분석)

  • Seungbum Hong;Jieun Oh;Jaegyu Cha;Kyungeun Lee
    • Korean Journal of Ecology and Environment
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    • v.56 no.4
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    • pp.363-374
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    • 2023
  • The limitation in deriving the species richness representing the entire country of South Korea lies in its relatively short history of species field observations and the scattered observation data, which has been collected by various organizations in different fields. In this study, a comprehensive compilation of the observation data for plants held by agencies under the Ministry of Environment was conducted, enabling the construction of a time series dataset spanning over 100 years. The data integration was carried out using minimal criteria such as species name, observed location, and time (year) followed by data verification and correction processes. Based on the integrated plant species data, the comprehensive collection of plant species in South Korea has occurred predominantly since 2000, and the number of plant species explored through these surveys appears to be converging recently. The collection of species survey data necessary for deriving national-level biodiversity information has recently begun to meet the necessary conditions. Applying the Chao 2 method, the species richness of indigenous plants estimated at 3,182.6 for the 70-year period since 1951. A minimum cumulative period of 7 years is required for this estimation. This plant species richness from this study can be a baseline to study future changes in species richness in South Korea. Moreover, the integrated data with the estimation method for species richness used in this study appears to be applicable to derive regional biodiversity indices such as for local government units as well.