• Title/Summary/Keyword: Compact

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A study on the granulometric and clastshape characteristic of gravel terrace deposit at Jeongdongjin area (정동진 단구 자갈층과 충진 물질의 입도 및 형상 특성에 대한 연구)

  • Kim, Jong Yeon;Yang, Dong Yoon;Shin, Won Jeong
    • Journal of The Geomorphological Association of Korea
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    • v.23 no.1
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    • pp.17-33
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    • 2016
  • Samples from newly exposed outcrop of sedimentary layers forming Jeongdongjin coastal terrace in Gangreung area are collected and analyzed to find the sedimentary environment. The site are located at the gentle hillslope of the terrace surface area. The height of the outcrop is about 8m and the altitude of it's highest part is 68~73m MSL. The lowest part of this out crop is the partly consolidated sand layer with gravel veneer within it. It is found that this part is not in-situ weathered sand stone through the OSL method. This sand layer is overlain by the gravel layer with sand matrix. The shapes of the gravels from this part are mainly 'platy', 'elongated', and 'bladed' by the index of Sneed and Folk(1958). In addition, mean roundness is not so high. It is sceptical to regard this part as marine sediments which are continuously exposed to erosional processes. The boundary between the lowest sand layer and gravel layer showing the abrupt change in forming material without any mixture or transitional zone, so gravels are seemed to deposited after some degree of consolidation of the lowest sand layer. In addition, the hight of the boundary between layers are changed by the place, so the surface of the partly consolidated sand layer is not flat and has irregularity on topography when it buried by gravels. Main part of this out crop is the poorly sorted coarse gravel(22.4mm) with sand matrix($1.36{\phi}$) layer with at least 2m thick covering the relatively fine gravels discussed above. Over 20% of particles have 'very platy', 'very elongated' and 'very bladed' shape and only less than 5% of particles have 'compact' shape, So this particles are also very hard to be regard as marine gravels which are abraded by marine processes. It can be concluded that this gravel layer formed by fluvial processes rather than coastal processes base on the form of the clast and sedimentary structure. The gravel layer is covered by fine($3{\sim}4{\phi}$) material layers of psudo-gleization which showing inter-bedding of red and white layers. Chemical composition of matrix and other fine materials should be analyzed in further studies. It is attempted to fine the burial ages of the sediment using OSL method, but failed by the saturation. So it can be assumed that these sediments have be buried over 120ka.

Axial Compression of Stub Columns for Concrete-filled Square Steel Tubes (일축 압축력을 받는 콘크리트충전 각형강관 단주의 구조적 거동)

  • Yoo, Yeong-Chan
    • Journal of the Korea Academia-Industrial cooperation Society
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    • v.22 no.2
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    • pp.617-624
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    • 2021
  • Concrete-filled steel tubular columns can improve the strength and deformation capacity of structures, thereby enabling the development of efficient structures. The Korean design standard (KDS41) regarding concrete-filled steel tubular structures, established by the architectural institute of Korea in 2005, was revised in 2009 and 2016. The objective was to understand the compressive strengths and deformation capacity of stub columns for concrete-filled square steel tubes under uniaxial compression and validate the KDS41's standard code for necessary corrections. Experiments were conducted on 26 specimens with parameters, such as the width-thickness ratio of cold-formed square tubes. The following values of the stub columns for concrete-filled square steel tubes were obtained: compressive strengths, relationship between the axial load and axial displacement, and failure modes. An analysis of these results enabled an understanding of the concrete-filled effect and the influence of the wide-thickness ratio. The compressive strengths of filled concrete saw a 9% increase compared to a state of uniaxial stress, which must be noted in a future edition of KDS41. After benchmarking the results regarding square steel tubes generated by cold forming to the guidelines provided by the KDS41, the KDS41's value of 2.26 for the limiting width-to-thickness ratio for the compact section was found to be inflated. With a safety concern, this paper proposes a more conservative value of 1.35.

Detection of Landslide-damaged Areas Using Sentinel-2 Image and ISODATA (Sentinel-2 영상과 자기조직화 분류기법을 활용한 산사태 피해지 탐지 - 2020년 곡성 산사태를 사례로 -)

  • KIM, Dae-Sun;LEE, Yang-Won
    • Journal of the Korean Association of Geographic Information Studies
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    • v.23 no.4
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    • pp.253-265
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    • 2020
  • As the risk of landslide is recently increasing due to the typhoons and localized heavy rains, effective techniques for the landslide damage detection are required to support the establishment of the recovery planning. This study describes the analysis of landslide-damaged areas using ISODATA(Iterative Self-Organizing Data Analysis Technique Algorithm) with Sentinel-2 image, regarding the case of Gokseong in August 7, 2020. A total of 4.75 ha of landslide-damaged areas was detected from the Sentinel-2 image using spectral characteristics of red, NIR(Near Infrared), and SWIR(Shortwave Infrared) bands. We made sure that the satellite remote sensing is an effective method to detect the landslide-damaged areas and support the establishment of the recovery planning, followed by the field surveys that require a lot of manpower and time. Also, this study can be used as a reference for the landslide management for the CAS500-1/2(Compact Advanced Satellite) scheduled to launch in 2021 and the Korean Medium Satellite for Agriculture and Forestry scheduled to launch in 2024.

Performance Evaluation of a Portable GC for Real-time Monitoring of Volatile Organic Compounds (휘발성 유기화합물의 실시간 모니터링을 위한 휴대형 GC의 성능 평가)

  • You, Dong-Wook;Seon, Yeong-Sik;Oh, Jun-Sik;Yi, Bongyoon;Kim, Hyun Sik;Jung, Kwang-Woo
    • Journal of the Korean Chemical Society
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    • v.64 no.6
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    • pp.327-333
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    • 2020
  • Performance of a portable GC that can be utilized for the real time determination of volatile organic compounds in air was evaluated. It employs purified/compressed ambient air as the carrier gas eliminating the need for high pressure gas tanks. The compact system with dimensions of 35 × 26 × 15 ㎤ and weight of 5 kg is powered by either a 24 V DC external adapter or battery pack. Chromatograms of the mixture sample including benzene, toluene, ethylbenzene, and oxylene at concentrations of 1 ppmv and 20 ppmv represent a good reproducibility: 3.79% and 0.48% relative standard deviations (RSDs) for peak area variations; 0.40% and 0.08% RSDs for retention times. The method detection limit was 0.09 ppmv. A 30 m long, 0.28 mm I.D. column operated at an optimal condition yielded a peak capacity of 61 with good resolution for a 10 min isothermal analysis. The relative standard deviations (RSD) of the peak area variations and retention times during consecutive measurements over 27 h were less than 2.4%RSD and 0.5%RSD, respectively. Thus, this instrument makes it suitable for continuous and field analysis of low-concentration VOC mixtures in the indoor/outdoor environment as well as the spillage accident of hazardous chemicals.

The Engineering Characteristics of the Sludge Mixed Soil (슬러지 혼합토의 공학적 특성)

  • Kim, JungUn;Kim, MyeongKyun;Bae, WooSeok
    • Journal of the Korean GEO-environmental Society
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    • v.12 no.5
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    • pp.43-50
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    • 2011
  • As a result of population growth and economic growth, household and industrial wastes continue to rapidly increase every year. Especially, sewage sludge produced at final stage is increasing with the constant construction and putting in good order of the sewage plant. In addition to the government's prohibition for filling up the sludge, it became more and more difficult to discharge wastes to the sea as London Dumping Convention '96 came into effect. And sewage sludge and the livestock wastes are expected to be thoroughly prohibited from discharging to the sea from 2012. So we need desperately economical and useful alternatives to compact and reuse these wastes. The purpose of this study is to evaluate the utilization of solidified sludge-soil mixture as an enhancement and covering material. To determine the proper mixed ratio of solidified sludge, this study conducted basic physical properties tests, compaction tests, uniaxial compression tests, and permeability test. It was found that the higher the ratio of solidified sludge, the lower the coefficient of permeability. Upon the results of particle size distribution, the mixed ratio of solidified sludge that meet the enhancement material condition was 59% or lower for SP granite soil and 48% or lower for SM granite soil respectively.

A Study of Prestige Fashion Brands' Visual Identities on Visual Semiotic Analysis of Cosmetic Products' Packaging -Focused on Yves Saint Laurent and Giorgio Armani- (화장품 패키지의 시각기호학적 분석을 통한 패션 명품 브랜드의 시각적 정체성 연구 - 입생로랑과 조르지오 아르마니의 사례를 중심으로 -)

  • Lee, Mi-jin;Jeon, Hyeong-yeon
    • Journal of Communication Design
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    • v.64
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    • pp.64-75
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    • 2018
  • Luxury fashion brands, which have dominated the market of high-priced apparel, bags and shoes, are recently showing changes of stepping into the cosmetics market. The purpose of this study is to examine how luxury fashion brand identity is transferred to cosmetic brand while expanding into luxury cosmetic brand, and to analyze the plastic signs of cosmetic package design and to analyze visual identity through a semi-symbolic system. Therefore, in this study, we tried to analyze the visual semiotic analysis of the package design such as the cushion compact, the lip tint and the brand logo which appeared in the popular product line of the fashion luxury brand such as Yves Saint Laurent and Armani. As a result of the analysis, this study has identified the semantic qualities expressed by each plastic element through the visual semiotic analysis process of the cosmetic package of Yves Saint Laurent and Giorgio Armani. These traits were found to be used as visual signs to reveal the 'Classicism' identity pursued by Yves Saint Laurent and the 'Baroque' identity pursued by Armani. Based on the results of this study, this study finds that the brand identity as a fashion brand is not transferring to the visual identity of cosmetic brands in the case of Yves Saint Laurent. On the other hand, this study found that Armani uses visual communication strategies to effectively transfer the brand identity as a fashion brand to the visual identity of cosmetic brands. On these two different results, it is necessary to examine whether luxury fashion brands and also Korean fashion brands are expanding into the cosmetics market and how they can better grasp the existing brand identity and apply it to the communication strategies of cosmetics brands.

Parvatrema duboisi (Digenea: Gymnophallidae) Life Cycle Stages in Manila Clams, Ruditapes philippinarum, from Aphae-do (Island), Shinan-gun, Korea

  • Jung, Bong-Kwang;Chang, Taehee;Shin, Hyejoo;Ryoo, Seungwan;Hong, Sooji;Lee, Jeonggyu;Song, Hyemi;Cho, Jaeeun;Kim, Deok-Gyu;Jun, Hojong;Kim, Min-Jae;Won, Eun Jeong;Han, Eun-Taek;Shin, Eun-Hee;Chai, Jong-Yil
    • Parasites, Hosts and Diseases
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    • v.59 no.1
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    • pp.83-88
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    • 2021
  • Life cycle stages, including daughter sporocysts, cercariae, and metacercariae, of Parvatrema duboisi (Dollfus, 1923) Bartoli, 1974 (Digenea: Gymnophallidae) have been found in the Manila clam Ruditapes philippinarum from Aphae-do (Island), Shinan-gun, Jeollanam-do, Korea. The daughter sporocysts were elongated sac-like and 307-570 (av. 395) ㎛ long and 101-213 (av. 157) ㎛ wide. Most of the daughter sporocysts contained 15-20 furcocercous cercariae each. The cercariae measured 112-146 (av. 134) ㎛ in total length and 35-46 (av. 40) ㎛ in width, with 69-92 (av. 85) ㎛ long body and 39-54 (av. 49) ㎛ long tail. The metacercariae were 210-250 (av. 231) ㎛ in length and 170-195 (av. 185) ㎛ in width, and characterized by having a large oral sucker, genital pore some distance anterior to the ventral sucker, no ventral pit, and 1 compact or slightly lobed vitellarium, strongly suggesting P. duboisi. The metacercariae were experimentally infected to ICR mice, and adults were recovered at day 7 post-infection. The adult flukes were morphologically similar to the metacercariae except in the presence of up to 20 eggs in the uterus. The daughter sporocysts and metacercariae were molecularly (ITS1-5.8S rDNA-ITS2) analyzed to confirm the species, and the results showed 99.8-99.9% identity with P. duboisi reported from Kyushu, Japan and Gochang, Korea. These results confirmed the presence of various life cycle stages of P. duboisi in the Manila clam, R. philippinarum, playing the role of the first as well as the second intermediate host, on Aphae-do (Island), Shinan-gun, Korea.

The Analysis and Preparation Guideline of Survey for Smart-City -Focused on the Case Study of Geumsan-gun- (스마트시티사업을 위한 설문결과 분석과 추진 방향 -도농복합도시 금산군의 사례-)

  • Nam, Yun-Cheol;Park, Eun-Yeong
    • Journal of the Korea Academia-Industrial cooperation Society
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    • v.22 no.3
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    • pp.422-428
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    • 2021
  • This study surveyed residents and public officials for the projects to make smart-city plans of Geumsan-gun. First, domestic and foreign cases related to smart city projects were reviewed. The local status of Geumsan-gun was investigated regarding various aspects of the natural, social, urban environment, and smart-city facilities. The survey results were as follows. Overall, more than half of the survey respondents said they were satisfied with their housing quality. Several problems in their areas, such as inefficient welfare system, shortage of parking space, and industrial infrastructure, were reported. On the other hand, tourism and leisure facilities, health care support systems, industries to boost the economy, and the job market were also important issues. The problem was that the regional problems mentioned above were not in line with their preferences for smart-city services. The implications of the survey results could be summed up as follows. The groupware surveys of Geumsan-gun should be used as survey tools, whereas IT survey tools (Google, Survey Monkey, etc.) should be used for locals. In particular, a survey targeting residents should ask plain and compact questions taking advantage of local gatherings. It is also important to have a pilot-survey with relevant public officials and select related projects and regional issues. The survey of local residents and public officials is a prerequisite for promoting smart city projects. The smart city project shall reflect the needs of residents while solving community problems by considering the survey results and local conditions.

Evaluation of Mechanical Properties and Alkali-Silica Reaction of High Strength Mortar Using Waste Glass Sand (폐유리 잔골재를 치환한 고강도 모르타르의 역학적 특성 및 알칼리-실리카 반응 평가)

  • Eu, Ha-Min;Kim, Gyu-Yong;Choe, Gyeong-Cheol;Son, Min-Jae;Nam, Jeong-Soo
    • Journal of the Korean Recycled Construction Resources Institute
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    • v.8 no.4
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    • pp.528-536
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    • 2020
  • In this study, high strength mortar and normal strength mortar using waste glass sand were evaluated. The main parameters studied were mechanical properties, alkali-silica reaction(ASR) and residual mechanical properties after ASR. As a result of this experiment, it was found that the increase in strength of the mortar has a limitation in improving the slip of the waste glass sand(GS), and rather, it causes a larger ASR. However, the possibility of improving the slip of GS was confirmed by the temporary increase of initial residal compressive and flexural strength of the mortar containing GS after the ASR. Therefore, to improve the slip of GS, the additional research is required, such as modification of the surface of GS and the incorporation of a binder which can increase the strength and makes matrix compact.

Design of a Compact GPS/MEMS IMU Integrated Navigation Receiver Module for High Dynamic Environment (고기동 환경에 적용 가능한 소형 GPS/MEMS IMU 통합항법 수신모듈 설계)

  • Jeong, Koo-yong;Park, Dae-young;Kim, Seong-min;Lee, Jong-hyuk
    • Journal of Advanced Navigation Technology
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    • v.25 no.1
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    • pp.68-77
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    • 2021
  • In this paper, a GPS/MEMS IMU integrated navigation receiver module capable of operating in a high dynamic environment is designed and fabricated, and the results is confirmed. The designed module is composed of RF receiver unit, inertial measurement unit, signal processing unit, correlator, and navigation S/W. The RF receiver performs the functions of low noise amplification, frequency conversion, filtering, and automatic gain control. The inertial measurement unit collects measurement data from a MEMS class IMU applied with a 3-axis gyroscope, accelerometer, and geomagnetic sensor. In addition, it provides an interface to transmit to the navigation S/W. The signal processing unit and the correlator is implemented with FPGA logic to perform filtering and corrrelation value calculation. Navigation S/W is implemented using the internal CPU of the FPGA. The size of the manufactured module is 95.0×85.0×.12.5mm, the weight is 110g, and the navigation accuracy performance within the specification is confirmed in an environment of 1200m/s and acceleration of 10g.