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        1.
        2024.04 구독 인증기관·개인회원 무료
        3D 프린팅 콘크리트는 임의의 형상을 자유롭게 적층하여 제작할 수 있다는 장점을 가지고 있지만, 노즐의 구조 및 형상에 따라 곡선부의 출력 품질이 달라진다. 또한, 공기중에서 출력한 경우와 수중에 서 출력한 경우 그 품질이 달라진다. 본 연구에서는 고정 마감날을 가진 사각형 노즐을 이용하여 3D 프린팅 모르타르를 수중에서 곡선 형태로 출력하고 적층한 후 출력성능, 적층성능, 및 역학적성능을 평가하였다. 30 × 30 mm 사각형 개구부를 가지고 있고 노즐 끝 양 측면에 고정 마감날이 설치된 노 즐을 사용하였다. 사전 직선 출력시험에서 선정된 조건인 호퍼 회전속도 14 rpm, 노즐 이동 속도 2000 mm/min을 적용하여 출력하였고, 1층 높이를 30mm로 출력하여 5층 적층하였다. 출력 및 적층 결과, 직선부분의 표면은 양호한 반면 곡면부분, 특히 곡률이 큰 곡선부분의 바깥쪽에서 표면균열이 관찰되었다. 직선부분의 치수 일관성은 양호한 반면, 곡률 반경이 작은 곡선부분의 폭 차이가 나타났 다. 곡선부분의 밀도와 압축강도는 직선부분보다 낮았다. 이는 곡선부에서 직사각형 노즐 회전에 따른 재료 토출이 불균일하기 때문인데, 이러한 문제점을 보완할 수 있는 제어 기술 개발이 필요하다.
        2.
        2024.04 구독 인증기관·개인회원 무료
        FRP 복합재 중 CFRP(Carbon Fiber Reinforcement Plastic)는 현재 Rebar, Plate, Grid 등 다양한 형태로 RC 구조물에 내‧외부 보강재로써 사용되고 있다. 이 중 CFRP Grid의 경우 국내에서 상용화가 되지 않아 다른 형태의 보강재보다 성능 분석 및 평가 기준이 미흡한 실정이다. 이에 따라 본 연구에 서는 Grid의 Strand, 경계조건, ASTM 고정장치의 유무 등 다양한 실험을 통하여 CFRP 그리드의 인 장 성능평가를 진행하였다. 선행 연구에서는 CFRP Grid의 인장시험 고정단의 경계조건에 따른 영향 성 분석을 위해 ASTM D7205 및 ASTM D6637에 따라 Tap-Tap (Type 1), Tap-Mortor (Type 2) 로 구성하여 인장시험을 수행하였으며, 시편의 파단 형상 및 시험 결과값이 가장 안정적인 Type 2를 CFRP Grid의 고정단 경계조건으로 설정하였다. 이러한 선행 연구를 바탕으로 고온 노출에 따른 CFRP 그리드의 인장 성능시험 평가를 진행하였으며, 인장시험은 만능재료시험기 및 고성능 카메라를 활용하여 최대 응력과 탄성계수를 도출하였다. 온도는 FRP의 전이온도인 150℃ 이내의 130℃에서 각 Case 별 5개의 시편을 70분(Case 2), 100분(Case 3), 120분(Case 4), 150분(Case 5) 노출한 후, 고온 에 노출하지 않은 시편(Case 1)과 비교하였다. 실험 결과, Case 5와 Case 1을 비교하여 인장강도와 탄성계수는 각각 최대 51.32%, 44.4% 감소하였다. 결론적으로 고온 환경에서 지속적으로 노출될 경 우, CFRP Grid의 성능이 최대 절반 수준으로 감소 되며 RC 부재 내‧외부에 보강 시에 고온 조건을 면밀히 검토하여 성능 감소를 최소화할 필요가 있다고 판단된다.
        3.
        2023.12 KCI 등재 구독 인증기관 무료, 개인회원 유료
        PURPOSES : As the number of fixed traffic enforcement equipments increase rapidly, it is necessary to improve efficient operation and management plans. The aim of this study is to evaluate the factors influencing fixed traffic enforcement equipment failure. METHODS : This study utilized binary logistic regression analysis using the database provided by the Korean Road Traffic Authority to evaluate the factors affecting the failure of fixed traffic enforcement equipment. RESULTS : As a result of the evaluation of this study, the main factors affecting failure were red-light camera, old equipment, Jeju, National expressways, and equipment with low speed limits. CONCLUSIONS : This study can be used as basic data on the improvement of operation management plas for maintenance of traffic enforcement equipment. Through this study, it will be possible to establish a step-by-step plan with high efficiency comapared to the input of required manpower.
        4,000원
        4.
        2023.03 KCI 등재 구독 인증기관 무료, 개인회원 유료
        The records system is believed to have started in Italy in the 14th century in line with trade developments in Europe. In 1491, Luca Pacioli, a mathematician, and an Italian Franciscan monk wrote the first book that described double-entry accounting processes. In many countries, including Korea, the government accounting standards used single-entry bookkeeping rather than double-entry bookkeeping that can be aggregated by account subject. The cash-based and single-entry bookkeeping used by the government in the past had limitations in providing clear information on financial status and establishing a performance-oriented financial management system. Accordingly, the National Accounting Act (promulgated in October 2007) stipulated the introduction of double-entry bookkeeping and accrual accounting systems in the government sector from January 1, 2009. Furthermore, the Korean government has also introduced International Financial Reporting Standards (IFRS), and the System of National Accounts (SNA). Since 2014, Korea owned five national accounts. In Korea, valuation began with the 1968 National Wealth Statistics Survey. The academic origins of the valuation of national wealth statistics which had been investigated by due diligence every 10 years since 1968 are based on the 'Engineering Valuation' of professor Marston in the Department of Industrial Engineering at Iowa State University in the 1930s. This field has spread to economics, etc. In economics, it became the basis of capital stock estimation for positive economics such as econometrics. The valuation by the National Wealth Statistics Survey contributed greatly to converting the book value of accounting data into vintage data. And in 2000 National Statistical Office collected actual disposal data for the 1-digit asset class and obtained the ASL(average service life) by Iowa curve. Then, with the data on fixed capital formation centered on the National B/S Team of the Bank of Korea, the national wealth statistics were prepared by the Permanent Inventory Method(PIM). The asset classification was also classified into 59 types, including 2 types of residential buildings, 4 types of non-residential buildings, 14 types of structures, 9 types of transportation equipment, 28 types of machinery, and 2 types of intangible fixed assets. Tables of useful lives of tangible fixed assets published by the Korea Appraisal Board in 1999 and 2013 were made by the Iowa curve method. In Korea, the Iowa curve method has been adopted as a method of ASL estimation. There are three types of the Iowa curve method. The retirement rate method of the three types is the best because it is based on the collection and compilation of the data of all properties in service during a period of recent years, both properties retired and that are still in service. We hope the retirement rate method instead of the individual unit method is used in the estimation of ASL. Recently Korean government’s accounting system has been developed. When revenue expenditure and capital expenditure were mixed in the past single-entry bookkeeping we would like to suggest that BOK and National Statistical Office have accumulated knowledge of a rational difference between revenue expenditure and capital expenditure. In particular, it is important when it is estimated capital stock by PIM. Korea also needs an empirical study on economic depreciation like Hulten & Wykoff Catalog A of the US BEA.
        4,600원
        5.
        2023.02 KCI 등재 구독 인증기관 무료, 개인회원 유료
        A fixed-point iteration is proposed to integrate the stress and state variables in the incremental analysis of plastic deformation. The Conventional Newton–Raphson method requires a second-order derivative of the yield function to generate a complicated code, and the convergence cannot be guaranteed beforehand. The proposed fixed-point iteration does not require a second-order derivative of the yield function, and convergence is ensured for a given strain increment. The fixed-point iteration is easier to implement, and the computational time is shortened compared with the Newton–Raphson method. The plane-stress condition is considered for the biaxial loading conditions to confirm the convergence of the fixed-point iteration. 3-dimensional tensile specimen is considered to compare the computational times in the ABAQUS/explicit finite element analysis.
        4,000원
        7.
        2022.10 구독 인증기관·개인회원 무료
        Radionuclides stored in a radioactive waste repository over a long period of time might be leached through the barriers such as engineered rock (cement) and natural rock (granite). Organic complexing agents such as ethylenediaminetetraacetic acid (EDTA) and isosaccharinic acid (ISA) may also influence the mobility of radionuclides. In this study, a continuous fixed-column reactor packed with engineered and natural rocks was designed to investigate the effect of organic complexing agents on cesium mobility through cement and granite under anaerobic conditions. The influent flow rate of the mixed solution (organic complexing agent and cesium) at the column bottom was 0.1 mL/min, while that of groundwater was 0.2 mL/min, which was introduced between cement and granite layers in the middle of the column. The hydraulic properties such as diffusion coefficient and retardation factor were derived by a bromide tracer test. The effects of different operating parameters, such as initial cesium concentrations, initial EDTA or ISA concentrations, and bed size, on the cesium adsorption were investigated. The Thomas, Adams-Bohart, and Yoon-Nelson models were applied to the experimental data to predict the breakthrough curves using non-linear regression. These results suggest that organic complexing agents such as EDTA and ISA significantly influence the mobility of cesium in the barriers, indicating that the presence of complexing agents enhances the migration of cesium to the geosphere.
        9.
        2021.10 KCI 등재 구독 인증기관 무료, 개인회원 유료
        본 연구에서는 환경, 재료 물성 및 제작 등에서의 불확실성을 고려하여 130m급 고정식 해양구조물의 신뢰성 기반 최적설계를 수행 하였다. 구조물의 구조건전성을 엄밀하게 반영하기 위해 작용 및 허용 응력의 비인 UC 값을 신뢰성 해석 및 신뢰성 기반 최적설계의 제약조건으로 고려하였다. 해양구조물의 제작비용을 저감하기 위해 자켓형 지지구조물의 중량을 최소화하였다. 불확실성의 통계적 특성은 문헌 등을 참고하여 관측되거나 측정된 데이터를 기반으로 정의하였다. 자켓형 해양구조물의 신뢰성 해석과 신뢰 기반 최적 설계는 부재 수가 많아 계산 부담이 큼으로 문제의 차원을 축소하기 위해 응답의 중요성을 기준으로 설계변수를 선별할 수 있는 방법 을 제안한다. 또한 효율적인 계산을 위해 신뢰성 기반 최적설계를 수행하기 전 결정론적 최적설계를 먼저 수행하였다. 마지막으로, 도 출된 최적설계(안)을 기존 각 급 규정 기반 설계와 안전성 및 경제성 측면에서 비교 분석하였다.
        4,000원
        10.
        2021.06 KCI 등재 구독 인증기관 무료, 개인회원 유료
        PURPOSES : For vehicle-alone accidents with a high mortality rate, it is necessary to analyze the factors influencing the severity of roadside fixed-object traffic accidents. METHODS : A total of 313 roadside fixed obstacle traffic accidents, variables related to fixed obstacles, and variables related to road geometry were collected. The estimation model was constructed with data collected using an ordinal probit regression model. RESULTS : Piers, vertical slopes, and distances between roads and objects were the primary causes of increased accident severity. CONCLUSIONS : Countermeasures, such as object removal, relocation, clear zones, frangibles, breakaway poles, etc., are required for accident-prone or dangerous points.
        4,000원
        11.
        2021.02 KCI 등재후보 구독 인증기관 무료, 개인회원 유료
        후한대 중국에 전래된 불교는 위진남북조시대에 들어 승려와 사원이 크게 증가하였다. 사원과 승려의 증가는 체계적 관리를 위한 교단과 이를 관리할 계율 제정의 필요성이 대두되었다. 이러한 상황에서 道安(312~385)을 비롯한 竺僧郞, 慧遠 등은 승단의 지도자로서 계율 제정에 노력하였다. 도안이 계율로 정한 行香定座上經上講法은 이후 佛法처럼 중국에서 정착하였고, 『法苑珠林』에는 泰始 3년인 467년 보살계를 받은 費崇先이 매번 청경을 할 때는 늘 작미향로를 무릎 앞에 두고 하였다고 기록하고 있다. 위진남북조시대와 漢代 향로의 가장 큰 차이점은 불교의례용 향로의 유무이다. 이 시기 불교의례용 병향로의 등장은 앞에서도 언급한 것처럼 계율로서의 행향과 관련이 깊지만, 및 불교경전의 한역도 병향로의 등장에 큰 영향을 미친다. 한역 경전의 ‘手執香爐’, ‘手擎香 爐’는 당시의 향로를 고려했을 때 병향로이었을 것으로 판단된다. 계율이자 의례인 行香은 동진대의 고승 道安이 제정하였지만, 행향에 사용하는 병향로는 서역에서 전래된 병향로를 바탕으로 중국적 기형인 鵲尾形柄香爐를 만든 것으로 볼 수 있 다. 위진남북조시대에 등장한 병향로는 5세기 중반에는 鵲尾香爐로 불렀다. 현재와 같은 병향로를 사용한 것은 唐代로 燉煌 출토 P.3433호 문서와 S.1774호 문서 등을 통해 8세기 후반 이후 ‘長柄香爐’라는 명칭을 사용한 것을 알 수 있다. 위진남북조시대 병향로는 작미형병향로로 대표되며, 이 향로는 화형받침과 몸체, 반구형 금구, 까치꼬리 모양 손잡이로 구성된다. 작미형병향로는 중국 남조에서 시작되어 북조로 전래된 것으로 추정되는데, 남조에서는 5세기 중후반, 북조에서는 5세기 후반경부터 작미 형병향로를 사용하였을 것으로 추정되며, 양식적으로 반구형 금구의 크기와 손잡이의 모습에 변화가 나타나는 것을 알 수 있다. 위진남북조시대 불교의례용 거향로는 새로운 기형의 등장 없이 전대의 박산향로를 불교적으로 수용하였는데, 석각화상을 통해 확인할 수 있다. 위진남북조시대 불교의례용 거향로로 사용한 박산향로는 사용 공간과 위치에 따라 다른 모습으로 표현되었고, 北魏에서 隋代 로 가면서 점차 장식적으로 변화하는 것을 알 수 있다.
        6,900원
        14.
        2020.09 KCI 등재 구독 인증기관 무료, 개인회원 유료
        In veterinary medicine, anaesthesia is fundamental for many medical acts, as complementary tests or surgical procedures. This discipline has evolved enormously in recent years, both in terms of practices as well as in terms of materials and used molecules.The aim of the present study was to compare three anaesthetic protocols, using injectable anaesthesia Ketamine/xylazine/acepromazine, ketamine/xylazine, and ketamine/xylazine /meloxicam in rabbits. Nine adult males, Neo-Zealand breed rabbits, weighing between 2.5 and 3.5 Kg were randomly divided into three groups, housed indoor to accommodate the place of experiments to evaluate their effects on risk factors associated with peri-anaesthetic mortality, along with gastrointestinal complications, in order to establish a suitable anaesthetic protocol, coupled with continuous monitoring of the anaesthetized animal. The association of acepromazine, xylazine, and ketamine, which give a deep myorelaxation and remarkable analgesia, obtained the anaesthesia. Fixed products do not lead to any myorelaxation of the mandibular muscles. The addition of a non-steroidal anti-inflammatory drug increased the effect of the peri-anaesthetic analgesia. The protocol using acepromazine, xylazine, and ketamine is the best schema for the potentiated general anaesthesia in rabbit, because of its insignificant effect on the intestinal motility.
        4,000원
        15.
        2020.08 KCI 등재 구독 인증기관 무료, 개인회원 유료
        The area around a certain airbase was affected by the noise of military helicopters, which seriously reduced the quality of the living environment in the surrounding area. In this paper, an automatic noise measurement system is set at 3 measurement points around the flight path of the 00 flight field. The fixed noise monitoring system is set up to measure the aircraft noise every day。 and selects the measurement site to facilitate the impact of noise caused by helicopter flight on the surrounding life. There is also a manual noise level measurement of the helicopter's maximum noise level for 7 days at 3 locations. Calculate the WECPNL value of 3 measuring points. Analyze the correlation between the aircraft noise evaluation unit WECPNL-Lden.
        4,000원
        17.
        2019.02 KCI 등재 구독 인증기관 무료, 개인회원 유료
        합성보에 휨모멘트가 작용하면, 콘크리트 슬래브의 아랫면과 강재보의 윗면은 각각 인장력과 압축력에 의하여 팽창과 수축을 한다. 필연적으로 두 부재의 사이에서는 미끄러지려고 하는 수평전단력이 작용하게 되며, 이에 저항할 수 있는 전단 연결재의 역할이 매우 중요하다. 이 연구에서는 화약의 폭발력을 사용하여 강재보의 플랜지에 전단연결재를 고정하는 방법을 개발하였다. 개발 고정방법의 구조성능을 검증하기 위하여 보-기둥 접합부 실험과 유한요소해석을 수행하였다. 실험 및 해석결과를 기반으로 판단했을 때, 개발된 접합방식을 통하여 충분한 연성 및 강도를 확보할 수 있을 것으로 판단된다.
        4,000원
        19.
        2018.09 KCI 등재 구독 인증기관 무료, 개인회원 유료
        As a method of seismic-design for pile-supported wharves, equivalent static analysis, response spectrum analysis, and time history analysis method are applied. Among them, the response spectrum analysis is widely used to obtain the maximum response of a structure. Because the ground is not modeled in the response spectrum analysis of pile-supported wharves, the amplified input ground acceleration should be calculated by ground classification or seismic response analysis. However, it is difficult to calculate the input ground acceleration through ground classification because the pile-supported wharf is build on inclined ground, the methods to calculate the input ground acceleration proposed in the standards are different. Therefore, in this study, the dynamic centrifuge model tests and the response spectrum analysis were carried out to calculate the appropriate input ground acceleration. The pile moment in response spectrum analysis and the dynamic centrifuge model tests were compared. As a result of comparison, it was shown that the response spectrum analysis results using the amplified acceleration in the ground surface were appropriate.
        4,300원
        20.
        2018.07 구독 인증기관·개인회원 무료
        While previous research has demonstrated the effect of implicit theories (i.e. the belief whether human attributes are fixed or malleable) on attitudes and behaviors in many domains, such a relationship has not been investigated in the domain of beauty. In this research, we examine the effect of implicit theories of beauty on how consumers access their actual versus ideal self, and how they experiment the self, in turn influencing brand variety seeking. We theorize that believing beauty is fixed (versus malleable) would make the ideal, desired self more accessible, as entity theorists tend to orient more towards performance goals, ones that ensure the desired judgments (Dweck, Hong, & Chiu, 1993) while incremental theorists strive to enhance their ability (i.e. learning goals) (Dweck & Leggett, 1988). In an experiment using a reaction time task, we found that participants who were primed with an incremental theory of beauty (i.e. beauty is malleable) took longer to react to words that describe their ideal self compared to words that describe their actual self. On the contrary, participants who were primed with the entity theory of beauty (i.e. beauty is fixed) reacted towards ideal self related words as quick as the actual self related words. Results from this experiment shows that when people believe is fixed, their ideal self is as accessible as their actual self. Believing beauty is fixed activates the yearn to possess characteristics that one desires, making the ideal, desired self more accessible. We further examined the effect of implicit theories of beauty on experimenting tendency and brand variety seeking, as experimenting different looks by using cosmetic products might be a way to experience multiple ideal selves. With a sample of over 1200 female consumers in four countries, including two Asian countries (Indonesia and Thailand) and two Western countries (the UK and Australia), we found a consistent pattern that the beauty is fixed (vs. malleable) belief is associated with greater tendency to experiment with beauty looks, which in turn leads to higher variety seeking of beauty brands. This result demonstrated that beauty essentialism can be a universal mechanism that drive behaviour in a beauty domain. Our finding provides insights for the marketing of beauty products. We show that beauty essentialism is a factor that drives consumer’s desire for their ideal self, similarly drives the tendency to experiment with new makeup looks as a way to express the multiple ideal selves. The belief whether beauty is fixed or malleable is thus a factor that customer segmentation can be based on. Further, communicating the message that beauty is fixed might motivate the consumers to try out new makeup products. Our findings further shed lights on some of the strategies that are currently implemented by companies. For instance, does Dove’s Real Beauty campaign really encourage consumers to embrace their actual beauty, or does it in fact make them desire for the ideal beauty even more?
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