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A Study on the Meaning of School Space: Criticism and Alternatives (학교 공간에 관한 의미 탐색: 비판과 대안)

  • Kim, Dal-Hyo
    • Journal of the Korean Institute of Educational Facilities
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    • v.26 no.4
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    • pp.3-10
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    • 2019
  • In school facilities, space is the basic framework. The structure and arrangement of space will provide the form and feel of school facilities. In order to become a high-quality school facility, it is necessary to focus on the educational, human and ecological aspects of the instructor and learner until the space is conceived, designed and completed. However, even when public education was introduced in the past, it did not become a school space considering this aspect. The school space, which focuses on efficiency and labor production, is a school space that reflects the characteristics of a factory-type school, which has been occupied by a large number until recently. Although efforts to improve the quality of school facilities have been attempted in recent years, there is also a need to pursue more active changes. Future-oriented and progressive school spaces include flexibility, connectivity, individualization, diversity(creativity). In other words, space should be flexible so that it can be used faithfully according to the educational situation, not the fixed and limited school space as in the past. In the future, the school space should be open and securely linked to the place where it is essential to complete community relations with the community. In addition, space should be flexible so that the school can meet the needs of each student as much as possible. And the school space should be transformed from the space design of the past fixed pattern to reflect the close relationship between spatial, psychological, physiological, and behavioral areas. When school space needs to shift away from the past and change in a new future-oriented direction, the remaining tasks should be presented with specific characteristics and content of the direction. And the function of the consignment should be handled by related research. Although the text of this study reveals the characteristics of future-oriented school space, more concrete and empirical research results should be presented by subsequent research at home and abroad. It is necessary to reduce trial and error in creating a future-oriented school space where both professors and learners can be satisfied by analyzing the common points and differences between the results of the study. In order to do this, it is necessary to make efforts to approach such research based on the participation of the subjects who teach and learn directly at the school site.

Analysis of the Behavior Characteristics of Pile Foundations Responding to Ground Deformation (지반 변형 대응형 말뚝 기초의 거동 특성 분석)

  • Lee, Junwon;Shin, Sehee;Lee, Haklin;Kim, Dongwook;Lee, Kicheol
    • Journal of the Korean Geosynthetics Society
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    • v.19 no.4
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    • pp.21-32
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    • 2020
  • As the global large-scale infrastructure construction market expands, the construction of civil engineering structures in extreme environments such as cold or hot regions is being planned or constructed. Accordingly, the construction of the pile foundation is essential to secure the bearing capacity of the upper structure, but there is a concern about loss of stability and function of the pile foundation due to the possibility of ground deformation in extreme cold and hot regions. Therefore, in this study, a new type of pile foundation is developed to respond with the deformation of the ground, and the ground deformation that can occur in extreme cold and hot region is largely divided into heaving and settlement. The new type of pile foundation is a form in which a cylinder capable of shrinkage and expansion is inserted inside the steel pipe pile, and the effect of the cylinder during the heaving and settlement process was analyzed numerically. As a result of the numerical analysis, the ground heaving caused excessive tensile stress of the pile, and the expansion condition of the cylinder shared the tensile stress acting on the pile and reduced the axial stress acting on the pile. Ground settlement increased the compressive stress of the pile due to the occurrence of negative skin friction. The cylinder must be positioned below the neutral point and behave in shrinkage for optimum efficiency. However, the amount and location of shrinkage and expansion of cylinder must comply with the allowable displacement range of the upper structure. It is judged that the design needs to be considered.

Evaluation of the effects of Hangover-releasing agent containing freeze-dried mature silkworm larval powder (SMSP) on alcohol metabolism and hangover improvement (숙잠 함유 복합물의 알코올 대사 및 숙취개선 효능평가)

  • Woo, Miseon;Cha, Ji Hyeon;Kim, Yonghwan;Kang, Hee-Taik;Kim, Hyeondok;Cho, Kyong Won;Park, Sung Sun;Lee, Jong Hun
    • Korean Journal of Food Science and Technology
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    • v.53 no.1
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    • pp.72-77
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    • 2021
  • Silkworms have traditionally been used to produce silk and textiles. However, steamed and freeze-dried mature silkworm larval powder (SMSP) contain large amounts of amino acids, vitamins, and essential minerals. In this study, we investigated the potential of SMSP as a hangover-relieving agent. Thirty individuals who met the selection criteria and exclusion criteria were included in the study and subsequently underwent a double-blind, randomized, placebo-controlled, cross-design human application test. Importantly, the test product containing SMSP (CKDHC) was proven to alleviate hangovers through a significant reduction in the plasma concentration of acetaldehyde in the context of an alcohol-induced hangover model. In particular, from 0.5 h after SMSP intake, the blood acetaldehyde concentration (mg/L), area under the time curve (AUC; indicating the degree of bioabsorption of blood acetaldehyde), and the highest blood acetaldehyde concentration (Cmax) were reduced. Altogether, these results suggest that the test product (CKDHC) exhibits an accelerated hangover-relieving effect.

Network Performance Verification for Next-Generation Power Distribution Management System Using FRTU Simulator (FRTU 시뮬레이터를 이용한 차세대 배전지능화시스템 네트워크 성능검증)

  • Yeo, Sang-Uk;Son, Sung-Yong
    • The Journal of Korea Institute of Information, Electronics, and Communication Technology
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    • v.13 no.6
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    • pp.523-529
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    • 2020
  • Power distribution management system is essential for the efficient management and operation of power distribution networks. The power distribution system is a system that manages the distribution network based on IT, and has been evolving along with the development of the power industry. The current power distribution system is designed to operate at a relatively low network transmission speed based on the independent operation of the main equipment. However, due to distributed resources such as photovoltaic or energy storage devices, which are rapidly increasing in popularity in recent years, the operation of future distribution environments is becoming more complex, and various information needs to be collected in real time. In this study, the requirements of the next-generation power distribution system were derived to overcome the limitations of the existing power distribution system, and based on this, the communication network system and performance requirements for the distribution system were defined. In order to verify the performance of the designed system, a software-based terminal device simulator was developed because it takes excessive time and cost to introduce a large-scale system such as a power distribution system. Using the simulator, a test environment similar to the actual operation was established, and the number of terminal devices was increased up to 1,000. The proposed system was shown to satisfy the requirements to support the functions of the next-generation power distribution system, recording less than 10 % of the communication network bandwidth.

Surface Milling for the Study of Pore Structure in Shale Reservoirs (셰일 저류층 내 공극 구조 연구를 위한 표면 밀링)

  • Park, Sun Young;Choi, Jiyoung;Lee, Hyun Suk
    • Korean Journal of Mineralogy and Petrology
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    • v.33 no.4
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    • pp.419-426
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    • 2020
  • Understanding the pore structure including pore shape and connectivity in unconventional reservoirs is essential to increase the recovery rate of unconventional energy resources such as shale gas and oil. In this study, we found analysis condition to probe the nanoscale pore structure in shale reservoirs using Focused Ion Beam (FIB) and Ion Milling System (IMS). A-068 core samples from Liard Basin are used to probe the pore structure in shale reservoirs. The pore structure is analyzed with different pretreatment methods and analysis condition because each sample has different characteristics. The results show that surface milling by FIB is effective to obtain pore images of several micrometers local area while milling a large-area by IMS is efficient to observe various pore structure in a short time. Especially, it was confirmed that the pore structure of rocks with high content of carbonate minerals and high strength can be observed with milling by IMS. In this study, the analysis condition and process for observing the pore structure in the shale reservoirs is established. Further studies are needed to perform for probing the effect of pore size and shape on the enhancement of shale gas recovery.

Technical Development for Extraction of Discontinuities in Rock Mass Using LiDAR (LiDAR를 이용한 암반 불연속면 추출 기술의 개발 현황)

  • Lee, Hyeon-woo;Kim, Byung-ryeol;Choi, Sung-oong
    • Tunnel and Underground Space
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    • v.31 no.1
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    • pp.10-24
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    • 2021
  • Rock mass classification for construction of underground facilities is essential to secure their stabilities. Therefore, the reliable values for rock mass classification from the precise information on rock discontinuities are most important factors, because rock mass discontinuities can affect exclusively on the physical and mechanical properties of rock mass. The conventional classification operation for rock mass has been usually performed by hand mapping. However, there have been many issues for its precision and reliability; for instance, in large-scale survey area for regional geological survey, or rock mass classification operation by non-professional engineers. For these reasons, automated rock mass classification using LiDAR becomes popular for obtaining the quick and precise information. But there are several suggested algorithms for analyzing the rock mass discontinuities from point cloud data by LiDAR scanning, and it is known that the different algorithm gives usually different solution. Also, it is not simple to obtain the exact same value to hand mapping. In this paper, several discontinuity extract algorithms have been explained, and their processes for extracting rock mass discontinuities have been simulated for real rock bench. The application process for several algorithms is anticipated to be a good reference for future researches on extracting rock mass discontinuities from digital point cloud data by laser scanner, such as LiDAR.

Case Analysis of Seismic Velocity Model Building using Deep Neural Networks (심층 신경망을 이용한 탄성파 속도 모델 구축 사례 분석)

  • Jo, Jun Hyeon;Ha, Wansoo
    • Geophysics and Geophysical Exploration
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    • v.24 no.2
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    • pp.53-66
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    • 2021
  • Velocity model building is an essential procedure in seismic data processing. Conventional techniques, such as traveltime tomography or velocity analysis take longer computational time to predict a single velocity model and the quality of the inversion results is highly dependent on human expertise. Full-waveform inversions also depend on an accurate initial model. Recently, deep neural network techniques are gaining widespread acceptance due to an increase in their integration to solving complex and nonlinear problems. This study investigated cases of seismic velocity model building using deep neural network techniques by classifying items according to the neural networks used in each study. We also included cases of generating training synthetic velocity models. Deep neural networks automatically optimize model parameters by training neural networks from large amounts of data. Thus, less human interaction is involved in the quality of the inversion results compared to that of conventional techniques and the computational cost of predicting a single velocity model after training is negligible. Additionally, unlike full-waveform inversions, the initial velocity model is not required. Several studies have demonstrated that deep neural network techniques achieve outstanding performance not only in computational cost but also in inversion results. Based on the research results, we analyzed and discussed the characteristics of deep neural network techniques for building velocity models.

Oil Storage Tank Inspection using 3D Laser Scanner (3D 레이저스캐너를 활용한 유류 저장탱크의 검사)

  • Park, Joon-Kyu;Lee, Keun-Wang
    • Journal of the Korea Academia-Industrial cooperation Society
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    • v.21 no.12
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    • pp.867-872
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    • 2020
  • Oil storage tanks are a major structure in chemical industrial complexes. Damage to the structure due to natural disasters or poor management can cause additional damage, such as leakage of chemicals, fire, and explosion, so it is essential to understand the deformation. In this study, data on oil storage tanks were acquired using a 3D laser scanner, and various analyzes were performed for storage tank management by comparing them with design data. Modeling of the oil storage tank was performed using the data and design drawings acquired by a 3D laser scanner. An inspection of the oil storage tank was effectively performed by overlapping. In addition, cross-sectional and exploded views of the deformation were produced to generate visible data on the deformation of the facility, and it was suggested that the oil storage tank had a maximum deformation of -7.16mm through quantitative analysis. Data that can be used for additional work was obtained by producing drawings to be precisely inspected for areas with large deformation. In the future, an inspection of oil storage tanks using 3D laser scanners is quantitative and visible data on oil storage tank deformation. This will greatly improve the efficiency of facility management by rebuilding it.

Analysis of UAV-based Multispectral Reflectance Variability for Agriculture Monitoring (농업관측을 위한 다중분광 무인기 반사율 변동성 분석)

  • Ahn, Ho-yong;Na, Sang-il;Park, Chan-won;Hong, Suk-young;So, Kyu-ho;Lee, Kyung-do
    • Korean Journal of Remote Sensing
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    • v.36 no.6_1
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    • pp.1379-1391
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    • 2020
  • UAV in the agricultural application are capable of collecting ultra-high resolution image. It is possible to obtain timeliness images for phenological phases of the crop. However, the UAV uses a variety of sensors and multi-temporal images according to the environment. Therefore, it is essential to use normalized image data for time series image application for crop monitoring. This study analyzed the variability of UAV reflectance and vegetation index according to Aviation Image Making Environment to utilize the UAV multispectral image for agricultural monitoring time series. The variability of the reflectance according to environmental factors such as altitude, direction, time, and cloud was very large, ranging from 8% to 11%, but the vegetation index variability was stable, ranging from 1% to 5%. This phenomenon is believed to have various causes such as the characteristics of the UAV multispectral sensor and the normalization of the post-processing program. In order to utilize the time series of unmanned aerial vehicles, it is recommended to use the same ratio function as the vegetation index, and it is recommended to minimize the variability of time series images by setting the same time, altitude and direction as possible.

A Study on Possibility of Improvement of MIR Brightness Temperature Bias Error of KOMPSAT-3A Using GEOKOMPSAT-2A (천리안2A호를 이용한 다목적실용위성3A호 중적외선 밝기 온도 편향오차 개선 가능성 연구)

  • Kim, HeeSeob
    • Journal of the Korean Society for Aeronautical & Space Sciences
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    • v.48 no.12
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    • pp.977-985
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    • 2020
  • KOMPSAT-3A launched in 2015 provides Middle InfraRed(MIR) images with 3.3~5.2㎛. Though the satellite provide high resolution images for estimating bright temperature of ground objects, it is different from existing satellites developed for natural science purposes. An atmospheric compensation process is essential in order to estimate the surface brightness temperature from a single channel MIR image of KOMPSAT-3A. However, even after the atmospheric compensation process, there is a brightness temperature error due to various factors. In this paper, we analyzed the cause of the brightness temperature estimation error by tracking signal flow from camera physical characteristics to image processing. Also, we study on possibility of improvement of MIR brightness temperature bias error of KOMPSAT-3A using GEOKOMPSAT-2A. After bias compensation of a real nighttime image with a large bias error, it was confirmed that the surface brightness temperature of KOMPSAT-3A and GEOKOMPSAT-2A have correlation. We expect that the GEOKOMPSAT-2A images will be helpful to improve MIR brightness temperature bias error of KOMPSAT-3A.