• Title/Summary/Keyword: 균열의 특징

Search Result 184, Processing Time 0.027 seconds

A qualitative Comparative Analysis of Welfare Regimes : Interventionist, Liberalist, and Confucian Welfare State (복지국가의 유형에 관한 질적 비교분석 : 개입주의, 자유주의 그리고 유교주의 복지국가)

  • Hong, Kyung-Zoon
    • Korean Journal of Social Welfare
    • /
    • v.38
    • /
    • pp.309-335
    • /
    • 1999
  • The purpose of this study is to classify welfare regimes using the method of qualitative comparative analysis(QCA). By formalizing the logic of qualitative analysis, QCA makes it possible to bring the logic and empirical intensity of qualitative approaches to studies that normally call for the use of quantitative methods. In QCA each case is conceived holistically, as a configuration of conditions, not a collection of scores on variables. Major findings of this study are as follows. Firstly, major explanations for welfare state differences are partly supported. Indicators relevant to each explanation can appear to be important only if other causal conditions are considered. For example, in the interventionist welfare states, high GDP per capita must be combined with the weakness of the Right and ethnic homogeneity. Otherwise, it can't discern interventionist from liberalist welfare states. Secondly, the equation for the interventionist welfare states includes multiple causal conjunctures. Many studies of welfare state find the same results. The third main finding is that IDV(individualism index) which is proxy for the weakness of informal network matters. Combining with other variables, IDV seems to be important in explaining the emergence of Confucian welfare states.

  • PDF

Strengthen Effect of RC Beam Overlaid or Repaired by VES-LMC (초속경 라텍스개질콘크리트로 덧씌우기 및 보수된 철근콘크리트보의 보강효과)

  • Choi, Sung-Yong;Yun, Kyong-Ku;Choi, Seung-Sic
    • Journal of the Korea Concrete Institute
    • /
    • v.20 no.4
    • /
    • pp.423-430
    • /
    • 2008
  • VES-LMC (very-early strength latex-modified concrete) has been widely used as repair material for bridge deck overlay or rehabilitation, because the overlaid or repaired could be opened to the traffic after 3 hours of curing. Although the field performance of VES-LMC generally indicates that it has an excellent bonding to the substrate and shows a long term performance, little quantitative data or research results have been presented in the literature on structural studies. The purpose of this study was to investigate the flexural behavior, interfacial performance, crack propagation, and strengthen effect of RC beam overlaid or repaired by VES-LMC through the 4-point flexural loading test. Two different types of RC beam were fabricated for repair and rehabilitation types. The test result showed that the strengthen effect, in term of flexural stiffness, increases as the depth of repair or overlay increases. More than 40% of stiffness was improved when the depth of repair was up to steel position. However, there was a little difference between 80 mm and 120 mm repaired beam. This means the repair depth must be considered. The interfacial behavior data showed that the repaired or overlaid beams had a little relative displacement. This means that two materials behave comparatively acting together. However, there were two specimens which had large displacement at the interface, because of poor bond strength. This suggested that interface treatment is one of the most important jobs in composite beams.

Possible Methods of Identifying Underground Cavities Using Seismic Waves (지진파를 이용한 지하 공동의 탐지 방법)

  • 김소구;마상윤;김지수
    • The Journal of Engineering Geology
    • /
    • v.6 no.3
    • /
    • pp.137-153
    • /
    • 1996
  • The purpose of this study is to investigate the possibilities of identifying and detecting underground cavities using seismic waves recorded by the fixed and mobile stations. During 18 months of field work we recorded chemical explosions near the Bongdarn station. Seismic Stations were installed on the free surface and underground inside the Samba mine. The seismograms at the fixed(lorg-term) seismic station show abrupt change of polarization characteristics which can he associated with the appearance of P-to-S converted phase(PS) at 150 ~ 200 msec after the first P arrival. This result indicates that converted phases are generated very near to the Bongdarn station at a depth of 190m. Shear-wave splitting phenomena have also been observeci The time delay between fast shear(fS) and slow shear(sS) waves ranges between 30 and 60 msec(average is 42 msec). However, exact time delay between the fast and the slow shear waves can not be accurately measured because of the very short time delay and limitation of sampling rate. Chemical explosion experiments were recorded at stations along various paths to contrast the seismic response of areas with and without cavities. The seismograms recorded at the stations installed at cavity areas show an abrupt change of polarization characteristics but not on the other stations. Seismic waves propagating through the cavity are characterized by the attenuation of high frequency waves and predominantly low frequency seismic waves after the S wave arrivals.

  • PDF

Enhancement of Cookie Quality by Microwave Treatment of Allergy Reaction-reduced "Ofree" Wheat Flour (마이크로웨이브 조사를 통한 알러지 저감 밀 오프리의 제과 가공적성 개선)

  • Park, JinHee;Yoon, Young-Mi;Son, Jae-Han;Choi, Chang-Hyun;Kim, Kyeong-Hoon;Kim, Kyeong-Min;Cheong, Young-Keun;Kang, Chon-Sick;Yang, Jinwoo
    • KOREAN JOURNAL OF CROP SCIENCE
    • /
    • v.64 no.4
    • /
    • pp.366-372
    • /
    • 2019
  • The use of flour milled from the Ofree wheat cultivar for baking attenuates allergies because some of the genes related to the allergic reaction have been knocked because some of its genes related to allergic reactions have been knocked down or knocked out through genetic mutation. However, the utilization of this flour is limited because the Ofree grain contains high content of total protein and gluten. Microwave irradiation has been used for changing the protein and gluten characteristics of wheat flour. Thus, this study investigated appropriate conditions of microwave irradiation to enhance the utilization of Ofree flour. As a result, when the flour was microwave-treated for 2 min, although the total protein and gluten contents were not changed, some qualities of the baked sugar-snap cookies, such as spread factor (diameter and thickness) and appearance (crack), were ameliorated. However, excessive heat treatment of the flour for over 3 min led to protein denaturation, which negatively affected the quality of the products. These results indicate that 2 min of microwave irradiation of flour that has high content of total protein and gluten can be used for the enhancement of cookie quality. Therefore, these results are expected to increase the utilization of Ofree wheat flour.

Study on the Characteristics of Gas Hydrate Layers Distributed in the Southern Ulleung Basin, the East Sea (동해 울릉분지 남부해역에 분포하는 가스 하이드레이트층의 특성 연구)

  • Huh Sik;Yoo Hai-Soo;Kim Han-Joon;Han Sang-Joon;Lee Yong-Kuk
    • The Korean Journal of Petroleum Geology
    • /
    • v.10 no.1_2 s.11
    • /
    • pp.18-22
    • /
    • 2004
  • To identify and interpret the distribution and the characteristics of the gas hydrate layers in the Ulleung Basin, we have surveyed and gathered the multi-channel seismic data, Chirp sub-bottom profiler, SeaBeam and 12 m piston core samples since 1996. In previous works, high-resolution seismic profiles showed acoustic anomalies such as acoustic void, acoustic turbidity and pock mark which indicate the presence of gas-charged sediments. The patterns of horizontal degassing cracks originated from free methane expansion is the strong indicator of shallow gas-charged sediments in the core samples. The observation of submarine slides and slumps from destabilizing the sediments in the southern part of the Ulleung Basin may also point out that the gas had been released from gas hydrate dissociation during lowstand of sea level. The multi-channel seismic data show BSR, blanking and phase reversal. The gas hydrate layers above which large-scale shallow gases are distributed exist at the depth of about 200 m from the sea-floor with water depth of 2,100 m. From the interpretation of seismic sections in the southern Ulleung Basin, gas hydrate layers occur in the Pleistocene-Holocene sediments. These gas-charged sediments, acoustic anomalies and BSR may be all related to the existence of gas hydrate layers in the study area.

  • PDF

Bond Strength Properties of CFRP Rebar in Concrete According to the Concrete Strength (콘크리트 강도에 따른 CFRP 보강근의 부착강도 특성)

  • Kim, Ho-Jin;Kim, Ju-Sung;Kim, Young-Jin;Choi, Jung-Wook;Park, Sun-Gyu
    • Journal of the Korean Recycled Construction Resources Institute
    • /
    • v.9 no.4
    • /
    • pp.569-577
    • /
    • 2021
  • CFRP(Carbon Fiber Reinforced Plastic) can maintain the same strength even if the diameter is reduced by about one - third, and the weight is about one - twentieth of that of the deformed reinforcing bars that have been used in the construction industry. In particular, it is resistant to corrosion, which is the weakest part of reinf orcing bars, and there is no concern that it will deteriorate over time, It is light and durable, so transportation costs are low and it is convenient for high-rise buildings. This paper experimentally clarifies the adhesive properties of CFRP and clarifies its behavior. That is, bond strength test was conducted with the directness of CFRP and the strength of concrete as experimental variables, and the bond mechanism was clarified experimentally. Furthermore, based on the experimental results, we constructed the bond stress-slip-strain relationship of CFRP compared to the existing deformed reinforcing bars.

Post-Historical Description and Spatial Attribute - Focusing on the Movie Paradise in Service - (탈역사 서술과 공간의 표상 - 영화 <군중낙원>을 중심으로)

  • Jin, Sung Hee
    • Cross-Cultural Studies
    • /
    • v.43
    • /
    • pp.405-428
    • /
    • 2016
  • The purpose of this paper is to examine the narrative-building method and the post-historical descriptive aspects of the movie Paradise in Service, which deals with the modern history of Taiwan. Although Paradise in Service tells the history of a certain time period, it focuses on the anguish and agony felt by people who lived during that age rather than on the meaning of historical events or interpretation of the past in terms of official historical discourse. That is, as it avoids looking at the present by composing a narrative in the descriptive historical context and from bearing weight from the viewpoint of realism, it gains the possibility of establishing a new field of discourse through a post-historical discussion using descriptive historical texts. However, the movie tries to create fantasy through a special type of licensed prostitution as a means of post-historical description. In other words, when this movie tries to reproduce the microscopic history of common people in trouble because of a historical tragedy, it considers only men and excludes "weak" women. Thus, although Paradise in Service has meaning in that it gives an example of how movies can disrupt official historical discourse and group memory and rewrite history by focusing on individuals, it is limited by its male-centrism.

Analysis of acoustic emission parameters according to failure of rock specimens (암석시편 파괴에 따른 acoustic emission 특성인자 분석)

  • Lee, Jong-Won;Oh, Tae-Min;Kim, Hyunwoo;Kim, Min-Jun;Song, Ki-Il
    • Journal of Korean Tunnelling and Underground Space Association
    • /
    • v.21 no.5
    • /
    • pp.657-673
    • /
    • 2019
  • A monitoring method based on acoustic emission (AE) sensor has been widely used to evaluate the damage of structures in underground rock. The acoustic emission signal generated from cracking in material is analyzed as various acoustic emission parameters in time and frequency domain. To investigate from initial crack generation to final failure of rock material, it is important to understand the characteristics of acoustic emission parameters according to the stress ratio and rock strength. In this study, uniaxial compression tests were performed using very strong and weak rock specimen in order to investigate the acoustic emission parameters when the failure of specimen occurred. In the results of experimental tests, the event, root-mean-square (RMS) voltage, amplitude, and absolute energy of very strong rock specimen were larger than those of the weak rock specimen with an increase of stress ratio. In addition, the acoustic emission parameters related in frequency were more affected by specification (e.g., operation and resonant frequency) of sensors than the stress ratio or rock strength. It is expected that this study may be meaningful for evaluating the damage of underground rock when the health monitoring based on the acoustic emission technique will be performed.

Study on the Characteristics of Materials and Manufacturing Techniques for the Mural Paintings in Daeunjeon at Ssanggyesa Temple, Jindo (진도 쌍계사 대웅전 벽화의 재질특성 및 제작기법 연구)

  • Lee, Na Ra;Yu, Yeong Gyeong;Lee, Hwa Soo
    • Journal of Conservation Science
    • /
    • v.37 no.6
    • /
    • pp.701-711
    • /
    • 2021
  • This study identifies the structure and material characteristics of the mural paintings in Daeungjeon at Ssanggyesa temple in Jindo by conducting scientific research and analysis including microscope examination, SEM-EDS, XRD, particle size analysis, and others. According to the analyses, the murals were considered to be of a typical soil mural style for Korean Buddhist murals, given that the walls were made of sand and soil and the murals had layers consisting of wall layers and a finishing layer. However, some finishing layer used calcite, while some ground layer used zinc white beneath the thick paint. In addition, there were similar features to those found on the surfaces of oil paintings such as cracks along with the paint layer, high gloss on surfaces, and thick brush strokes in many areas. It was found that the walls on which the murals were painted were made of soil but that the paint layer was created based on the oil painting technique using drying oil. It determined that the murals were painted in a unique painting style that is rarely found in other typical Buddhist murals in Korea.

Evaluation of bonding state of shotcrete lining using nondestructive testing methods - experimental analysis (비파괴 시험 기법을 이용한 숏크리트 배면 접착상태 평가에 관한 실험적 연구)

  • Song, Ki-Il;Cho, Gye-Chun;Chang, Seok-Bue;Hong, Eun-Soo
    • Journal of Korean Tunnelling and Underground Space Association
    • /
    • v.11 no.1
    • /
    • pp.71-83
    • /
    • 2009
  • Shotcrete is an important primary support for tunnelling in rock. The quality control of shotcrete is a core issue in the safe construction and maintenance of tunnels. Although shotcrete may be applied well initially onto excavated rock surfaces, it is affected by blasting, rock deformation and shrinkage and can debond from the excavated surface, causing problems such as corrosion, buckling, fracturing and the creation of internal voids. This study suggests an effective non-destructive evaluation method of the tunnel shotcrete bonding state applied onto hard rocks using the impact-echo (IE) method and ground penetration radar (GPR). To verify previous numerical simulation results, experimental study carried out. Generally, the bonding state of shotcrete can be classified into void, debonded, and fully bonded. In the laboratory, three different bonding conditions were modeled. The signals obtained from the experimental IE tests were analyzed at the time domain, frequency domain, and time-frequency domain (i.e., the Short- Time Fourier transform). For all cases in the analyses, the experimental test results were in good agreement with the previous numerical simulation results, verifying this approach. Both the numerical and experimental results suggest that the bonding state of shotcrete can be evaluated through changes in the resonance frequency and geometric damping ratio in a frequency domain analysis, and through changes in the contour shape and correlation coefficient in a time-frequency analysis: as the bonding state worsens in hard rock condition, the autospectral density increases, the geometric damping ratio decreases, and the contour shape in the time-frequency domain has a long tail parallel to the time axis. The correlation coefficient can be effectively applied for a quantitative evaluation of bonding state of tunnel shotcrete. Finally, the bonding state of shotcrete can be successfully evaluated based on the process suggested in this study.