검색결과

검색조건
좁혀보기
검색필터
결과 내 재검색

간행물

    분야

      발행연도

      -

        검색결과 3,959

        1.
        2024.03 KCI 등재 구독 인증기관 무료, 개인회원 유료
        Deep learning-based computer vision anomaly detection algorithms are widely utilized in various fields. Especially in the manufacturing industry, the difficulty in collecting abnormal data compared to normal data, and the challenge of defining all potential abnormalities in advance, have led to an increasing demand for unsupervised learning methods that rely on normal data. In this study, we conducted a comparative analysis of deep learning-based unsupervised learning algorithms that define and detect abnormalities that can occur when transparent contact lenses are immersed in liquid solution. We validated and applied the unsupervised learning algorithms used in this study to the existing anomaly detection benchmark dataset, MvTecAD. The existing anomaly detection benchmark dataset primarily consists of solid objects, whereas in our study, we compared unsupervised learning-based algorithms in experiments judging the shape and presence of lenses submerged in liquid. Among the algorithms analyzed, EfficientAD showed an AUROC and F1-score of 0.97 in image-level tests. However, the F1-score decreased to 0.18 in pixel-level tests, making it challenging to determine the locations where abnormalities occurred. Despite this, EfficientAD demonstrated excellent performance in image-level tests classifying normal and abnormal instances, suggesting that with the collection and training of large-scale data in real industrial settings, it is expected to exhibit even better performance.
        4,200원
        2.
        2024.03 KCI 등재 구독 인증기관 무료, 개인회원 유료
        This note summarizes the application of zooplankton indices for water quality management and estimation based on main research topics of articles focusing on wetland ecosystems, topics that are remained poorly investigated in S. Korea. The aquatic ecosystem-based consists of indices that respond to different target environmental factors, including environmental disturbance. Among the major indicator species and biota, we reviewed that management strategy for the wetland environment has to be focused more on small-sizes, in terms of zooplankton ecology and indices. The ecology of zooplankton communities in freshwater ecosystem has been the focus of an increasing number of studies since 2019, and considerable progress has been made in understanding the major mechanisms involved in regulating their abundance, diversity and spatio-temporal patterns. Even though studies on the freshwater ecosystem in Korea have a long history, a few of studies on zooplankton biota were conducted at wetlands. We suggested the candidate zooplankton indices proposed by the U.S. EPA and EU to suit Korean conditions. In the step of selecting metrics, the best available metrics are species-related variables, such as composition and abundance, as well as richness and diversity. Overall, in spite of several limitations, the development of a plankton-based multivariate assessment method in Korea wetlands is possible using mostly field research data. Later, it could be improved based on qualitative metrics on zooplankton, and with the emergence of further survey data. The present information can be used as basic information for researchers who are dealing with aquatic environments and its interaction with organisms.
        4,000원
        3.
        2024.03 구독 인증기관·개인회원 무료
        국토교통부 보고서 “2022 도로교 현황보고”에 따르면, 국내 교량의 수는 연간 2.9%씩 증가하고 있으며 그에 따라 보수 가 필요한 교량의 수도 늘어나는 추세이다. 교량 하부를 보수할 때 보통은 몰탈을 사용하여 보수해 왔고, 직접 보수하기 에는 작업자의 안전성 및 작업의 효율성이 떨어져 숏크리트를 사용하여 보수해 왔다. 숏크리트는 건식 숏크리트와 습식 숏크리트가 있다. 습식 숏크리트는 시멘트와 골재, 그리고 미리 혼합된 물이 호스를 통하여 이송되고 호스 끝에서 압축 공기가 이를 고속으로 분사하는 공법이다. 다만 재료를 미리 계량하고 배합한다는 한계가 재료 공급의 제약을 가져온다. 건식 숏크리트란 시멘트, 골재, 섬유 등 건조된 재료들이 호스로 빠르게 압송되어 노즐부에서 물과 만나 빠르게 분사되 는 공법이다. 이러한 공법은 장거리 압송 가능, 습식 숏크리트에 비해 상대적으로 적은 장비, 청소와 보수의 용이성, 쉬 운 적용성이 장점이다. 따라서 본 연구에서는 건식 숏크리트 공법을 채택하여 교량 슬래브 하부인 천정부에 대한 단면보 수를 진행하고자 한다. 배합설계는 혼합골재 입도곡선을 고려하고 실리카퓸은 중량의 3%를 차지한다. 연구결과 고압 살 수 및 건식 숏크리트의 현장 적용성은 우수하며, 작업의 용이성 등 교량 하부 구조물 보수에 대한 다양한 장점을 가질 수 있다고 사료된다.
        4.
        2024.02 KCI 등재 구독 인증기관 무료, 개인회원 유료
        역전기투석(reverse electrodialysis, RED)은 해수와 담수의 농도 차로부터 에너지를 얻는 이온교환막을 이용한 전 기막 공정이다. 해수와 담수에 포함된 다가 이온은 이온교환막의 고정 전하 그룹에 강하게 결합하여 높은 저항을 유발하며 uphill transport를 통해 개방회로 전압과 전력 밀도를 저하시킬 수 있다. 본 연구에서는 RED 응용을 위해 1가 이온 선택성 및 전기화학적 특성이 우수한 세공충진 음이온교환막(pore-filled anion-exchange membrane, PFAEM)을 제조하였다. 제조된 막의 1가 이온 선택성은 3.65였으며 동일 조건에서 1.27의 선택성을 갖는 상용막(ASE, Astom Corp.)보다 우수한 수준을 나 타내었다. 또한 제조된 막은 ASE 대비 낮은 전기적 저항 등 우수한 전기화학적 특성을 나타내었다. 0.459 M NaCl/0.0510 M Na2SO4의 해수와 0.0153 M NaCl/0.0017 M Na2SO4의 담수 조건에서 RED 성능을 평가한 결과 제조된 막을 적용하여 1.80 W/m2의 최대 전력 밀도를 얻었으며 이는 ASE 막 대비 40.6% 향상된 출력 성능이었다.
        4,300원
        5.
        2024.02 KCI 등재 구독 인증기관 무료, 개인회원 유료
        우리나라에서는 연간 250건 이상의 해양 기름유출사고가 발생하고 있으며, 이는 지역 사회 및 환경에 큰 영향을 미친다. 국제 협약 및 국내법에서는 오염자부담의 원칙을 바탕으로 기름유출에 대한 피해 배상을 유출 당사자에게 책임지도록 하고 있으며, 민·형사적 책임 규명을 위해 유출 행위자에 대한 적극적인 조사가 이루어지고 있다. 기름 유출사고의 행위자 조사의 중요성 확대에 따라서 CEN 15522-2, ASTM D 3248 등의 표준을 이용해 기름 시료 간의 유사성 판정을 하고 있다. 이 중 가장 활발히 활용되고 있는 유럽표준인 CEN 15522-2가 2023년 EN 15522-2로 3차 개정되었다. 본 연구는 EN 15522-2를 이용하여 국내 발생한 해양 기름유출사고 시료를 분석하고, 적용 성에 대하여 확인하였다. 그 결과 경질유 유출사고가 40% 이상을 차지하는 국내 유출사고의 특징을 비춰볼 때 Adamamtanes와 같은 저비 점의 물질이 추가된 EN 15522-2의 적용은 효용성이 높은 것으로 확인되었다.
        4,000원
        6.
        2024.02 KCI 등재 구독 인증기관 무료, 개인회원 유료
        PURPOSES : This study aims to propose drone-command standard operating procedure (SOP) guidelines and Analyze their potential application to increase the use and utility of drones in urban disaster situations. Although the effectiveness and efficiency of obtaining disaster-situation information through drones have been verified by previous studies and practical experience, a survey of actual drone usability indicated a utilization rate of only approximately 4.13%. METHODS : To provide guidance for improving drone command SOPs, prior research and relevant literature were reviewed to identify commonalities between disaster-response command and control and drone use. A sample of 73 active-duty firefighters, including incident commanders (ICs) and drone pilots, were surveyed and interviewed. The data were analyzed and categorized to establish the reasons why drones are not actively used in urban disaster-response procedures. RESULTS : The primary reasons identified for not actively utilizing drones in urban disaster areas were the lack of a drone command and control system and the lack of clear criteria for when to use drones in disaster situations. In addition, many problems were found in drone-operation procedures, including emergency flight approval, securing takeoff and landing sites, and accident burden due to urban flight obstacles. To address the issues identified, standards were proposed for the type, size, and scope of urban disasters requiring drone response; for accident-prevention on basic missions and through flight safety procedures; and for installing a video transmission and reception system to easily share drone video information with ICs. CONCLUSIONS : Application of the drone-command SOP guidelines to actual urban disaster situations by disaster type will help to improve the efficiency of information acquisition and flight safety. This is expected to enable increased drone utilization. In future, extension of the research reported in this paper beyond the Seoul metropolitan area via additional follow-up studies has the potential to establish applicability of the proposed SOP guidelines to a wide variety of environments and organizational characteristics.
        4,000원
        7.
        2024.02 KCI 등재 구독 인증기관 무료, 개인회원 유료
        In this study, a core-shell powder and sintered specimens using a mechanically alloyed (MAed) Ti-Mo powder fabricated through high-energy ball-milling are prepared. Analysis of sintering, microstructure, and mechanical properties confirms the applicability of the powder as a sputtering target material. To optimize the MAed Ti-Mo powder milling process, phase and elemental analyses of the powders are performed according to milling time. The results reveal that 20 h of milling time is the most suitable for the manufacturing process. Subsequently, the MAed Ti-Mo powder and MoO3 powder are milled using a 3-D mixer and heat-treated for hydrogen reduction to manufacture the core-shell powder. The reduced core-shell powder is transformed to sintered specimens through molding and sintering at 1300 and 1400oC. The sintering properties are analyzed through X-ray diffraction and scanning electron microscopy for phase and porosity analyses. Moreover, the microstructure of the powder is investigated through optical microscopy and electron probe microstructure analysis. The Ti-Mo core-shell sintered specimen is found to possess high density, uniform microstructure, and excellent hardness properties. These results indicate that the Ti-Mo core-shell sintered specimen has excellent sintering properties and is suitable as a sputtering target material.
        4,000원
        8.
        2024.02 KCI 등재 구독 인증기관 무료, 개인회원 유료
        PURPOSES : The objective of this study was to review roadway management strategies that can be utilized in the event of a radiological emergency, select feasible alternatives, and simulate a portion of the West Coast network to analyze the effectiveness of these strategies. METHODS : The methodology of the study involved reviewing the relevant literature, extracting the implications, establishing an analysis procedure, and selecting an effectiveness evaluation scale. Using a national transportation database, a network was constructed using Toba, a macroscopic model. RESULTS : A reverse-flow lane system was applied to the West Coast Expressway Glory IC–Hampyeong IC (total 25 km), and a plan to increase the number of lanes was applied to the Seokgyo Street–Shinpyeong Intersection on National Route 23 (total extension 28 km). Consequently, both road management strategies were found to be effective. CONCLUSIONS : This study examined roadway management strategies that can be utilized in the event of a radiological emergency, selected feasible alternatives, and simulated a portion of the West Coast network to verify the effectiveness of these strategies. In the case of reverse flow lanes, it is most effective when applied to expressways that can restrict the entrance and exit of vehicles. In the case of increasing the number of lanes, it is most effective when applied to general roads, and institutional arrangements should be made to enable two-way traffic to use the reserved shoulder lanes.
        4,000원
        9.
        2024.02 KCI 등재 구독 인증기관 무료, 개인회원 유료
        By developing molds and facilities to horizontally mold the functional part of the dry-cast concrete block, We intend to develop molds and a series of facilities to horizontally mold the functional part of the dry-cast concrete block to increase production per cycle while maintaining existing production methods and major facilities. In order to do so, CAE analysis is first required to develop molds and facilities for horizontally molding the functional part of the drycast concrete block in the horizontal direction. The procedure will be carried out by reviewing the validity of boundary conditions and physical properties, 3D modeling, grid generation, construction of analysis models, model validity, analysis according to frequency changes, and analysis according to physical properties. First, through the comparison of two-point support, three-point support, and two-point and three-point support in the constraint conditions, We would like to compare it with the actual molded product in the horizontal direction. But first of all, it is considered two-point support in the constraint conditions in this paper.
        4,300원
        10.
        2024.02 KCI 등재 구독 인증기관 무료, 개인회원 유료
        Occurrence of process environment changes, such as influent load variances and process condition changes, can reduce treatment efficiency, increasing effluent water quality. In order to prevent exceeding effluent standards, it is necessary to manage effluent water quality based on process operation data including influent and process condition before exceeding occur. Accordingly, the development of the effluent water quality prediction system and the application of technology to wastewater treatment processes are getting attention. Therefore, in this study, through the multi-channel measuring instruments in the bio-reactor and smart multi-item water quality sensors (location in bio-reactor influent/effluent) were installed in The Seonam water recycling center #2 treatment plant series 3, it was collected water quality data centering around COD, T-N. Using the collected data, the artificial intelligence-based effluent quality prediction model was developed, and relative errors were compared with effluent TMS measurement data. Through relative error comparison, the applicability of the artificial intelligence-based effluent water quality prediction model in wastewater treatment process was reviewed.
        4,800원
        11.
        2024.01 KCI 등재 구독 인증기관 무료, 개인회원 유료
        본 연구의 목적은 청소년 엘리트 운동선수를 위한 단기 의사소통 훈련 프로 그램이 의사소통 만족도, 집단응집력, 운동성과에 미치는 효과를 검증하는 데 있다. 본 연구에서는 대학생 운동선수를 대상으로 효과가 검증되었던 의사소통 훈련 프로그램을 참여 집단의 특성과 학교 현장 여건에 맞게 수정 및 보완하여 활용하였다. 연구참여자는 G시 소재의 고등학교 축구부를 대상으로 모집되었 고, 프로그램은 주 1회 100분씩 총 6회기 실시되었다. 프로그램의 효과검증을 위 해 양적 자료로 의사소통 만족도, 집단응집력, 운동성과 척도 점수가, 질적 자료 로 회기별 경험보고서가 수집되었다. 수집된 자료를 바탕으로 단기 의사소통 훈 련 프로그램의 효과를 검증한 결과는 다음과 같다. 첫째, 단기 의사소통 훈련 프 로그램의 양적 효과는 청소년 운동선수의 의사소통 만족도, 집단응집력, 운동성 과에 있어 유의하지 않았다. 둘째, 단기 의사소통 훈련 프로그램의 질적 효과는 청소년 운동선수에게 즐거움을 주고, 의사소통의 중요성을 인식시키며, 선수 간 의 관계 개선에 긍정적인 영향을 미치는 것으로 확인되었다. 양적 효과와 질적 효과의 상반된 결과에 대한 분석 및 해석은 논의에 제시하였다.
        5,700원
        12.
        2024.01 KCI 등재 구독 인증기관 무료, 개인회원 유료
        본 논문의 목적은 타 문화권 선교사의 크리스천 코칭 경험의 의미를 분석하여 크리스천 코칭을 수단으로 하는 멤버케어의 적용 가능성을 밝히고, 멤버케어를 지원하는 크리스천 코칭의 발전을 위한 기초자료를 제공하는 데 있다. 이를 위하 여 본 연구는 선교지에서 발생하고 있는 선교사들 간의 갈등, 부부 및 자녀 문제, 재정, 스트레스, 우울증, 위기, 추방, 코로나 팬데믹, 탈진으로 인한 중도탈락 등 많은 이유로 인해 선교사 돌봄의 문제가 부각되고 있다는 점을 논의하였다. 이러 한 논의를 바탕으로 임상적인 크리스천 코칭 프로그램의 참여 경험에 대한 연구 를 수행하기 위하여 본 연구는 질적 사례연구방법을 채택하였다. 타 문화권 선교 사의 크리스천 코칭 경험을 통해서 볼 때, 본 연구는 크리스천 코칭의 잠재적 멤 버케어 적용 가능성을 충분히 시사하고 있으며, 연구참여자들은 크리스천 코칭 이 전문가의 멤버케어의 영역에서 긍정적인 변화를 가져왔다고 진술하였다. 본 연구는 타 문화권 선교사의 멤버케어 방법으로 크리스천 코칭 이론을 본 격적으로 도입하여 활용하였으며, 선교와 코칭이 융합적인 맥락에서 활용되었 을 때, 선교적 시너지 효과를 낼 수 있음을 확인하였다. 또한 본 연구는 타 문화 권 선교사를 대상으로 하는 크리스천 코칭의 현장 임상을 통해 연구 결과를 얻 었으며, 복음의 도구와 선교적 방법론으로 크리스천 코칭의 이론과 실제를 다루 었다는 점에서 의의가 있다.
        7,000원
        13.
        2024.01 KCI 등재 SCOPUS 구독 인증기관 무료, 개인회원 유료
        New piezoelectric and triboelectric materials for energy harvesting are being widely researched to reduce their processing cost and complexity and to improve their energy conversion efficiency. In this study, BaTiO3 films of various thickness were deposited on Ni foams by R.F. magnetron sputtering to study the piezoelectric and triboelectric properties of the porous spongy structure materials. Then piezoelectric nanogenerators (PENGs) were prepared with spongy structured BaTiO3 and PDMS composite. The output performance exhibited a positive dependence on the thickness of the BaTiO3 film, pushing load, and poling. The PENG output voltage and current were 4.4 V and 0.453 μA at an applied stress of 120 N when poled with a 300 kV/cm electric field. The electrical properties of the fabricated PENG were stable even after 5,000 cycles of durability testing. The triboelectric nanogenerators (TENGs) were fabricated using spongy structured BaTiO3 and various polymer films as dielectrics and operated in a vertical contact separation mode. The maximum peak to peak voltage and current of the composite film-based triboelectric nanogenerator were 63.2 V and 6 μA, respectively. This study offers new insights into the design and fabrication of high output nanogenerators using spongy structured materials.
        4,000원
        14.
        2024.01 KCI 등재 구독 인증기관 무료, 개인회원 유료
        본 연구는 자살생존 배우자의 애도경험을 보다 새롭고 깊이 있게 탐구 하기 위한 목적으로 Aguirre와 Bolton(2014)이 제시한 질적 해석적 메 타통합 방법(Qualitative Interpretive Meta Synthesis, QIMS)을 적용 하였다. 연구의 목적은 1차 질적 문헌연구들을 수집하고 이를 체계적으 로 분석하여 자살생존 배우자들의 애도경험을 이해하고, 이들의 회복과 삶의 재건을 도울 수 있는 새로운 실천방안을 발굴하는 것이다. 이를 위 해 2010년부터 2023년 9월까지 국내에서 수행된 자살생존 배우자 애도 경험에 관한 7편의 질적 논문을 최종분석에 포함하였고, 자살생존 배우 자 34명의 진술을 분석하였다. 자료범위의 축소와 주제 추출 및 통합 과 정을 통해 새롭고 의미 있게 도출된 내용은 39개의 주제범주, 12개의 통 합주제로 결집하였다. 이를 다시 근거이론의 패러다임 모형에 재배열하 여 구조화하였다. 마지막으로 연구결과에 근거하여 자살생존 배우자들의 애도경험을 체계적으로 해석 기술했으며, 자살생존 배우자들의 회복을 돕는 실천방안을 제시했다.
        8,300원
        15.
        2023.12 KCI 등재 구독 인증기관 무료, 개인회원 유료
        Background: Cerebral palsy presents significant challenges in motor function for affected children. While conventional bottom-up approaches are common in physical therapy, there is increasing interest in the efficacy of the top-down approach. Objectives: To investigated the impact of applying the top-down approach in physical therapy for a child diagnosed with cerebral palsy, focusing on functional improvement and quality of life. Design: A single-case study. Methods: The patient was a 15-year-old boy with spastic diplegic cerebral palsy who was entering middle school. Cerebral palsy treatment approach of the top-down method (jumping rope) was used to guide and direct physical therapy. Results: The child improved in muscle strength of lower extremity, gross motor function, participation and self-esteem, but the pattern of his gait seemed to be more severe on tiptoe. When the child participated in a jumping rope class, he was able to do more than 10 jumps. Conclusion: The effectiveness of the top-down approach in enhancing functional outcomes and quality of life in children with cerebral palsy. It highlights the potential of this approach in pediatric physical therapy, warranting further research validation.
        4,000원
        16.
        2023.12 KCI 등재 구독 인증기관·개인회원 무료
        스마트팜형 시설 딸기에 예찰 없이 작물 정식 초기에 천적을 먼저 적용하는 생태공학적 Natural Enemy in First (NEF) 기법이 총채벌레류 와 진딧물류의 밀도에 미치는 영향을 확인하였다. 대조구는 약제를 처리하여 비교하였다. NEF 처리구에서 총채벌레류와 진딧물류의 천적과 서식 처로 참멋애꽃노린재와 Portulaca sp.를 적용하여 작기 종료시점까지 해충의 밀도를 대조구와 유사하게 효과적으로 관리할 수 있었다.
        17.
        2023.12 KCI 등재 구독 인증기관 무료, 개인회원 유료
        ROK Navy Landing Ship Fast(LSF-II) is equipped with special equipment that is not compatible with other combat ships due to special missions. So there are almost no maintenance capabilities except for simple repair parts replacement and maintenance parts. The researcher determined that the way to solve these problems was to apply Performance Based Logistics (PBL), and reviewed the cases of PBL applications abroad and domestically. To confirm the current maintenance capability, we visited LSF-II operation unit to identify maintenance capabilities for each mounted equipment, and interviews with operators and maintenance practitioners confirmed the limitations of outsourcing maintenance and the need to apply PBL. In order to analyze the effect of PBL application, the measure of effectiveness and measure of performance were selected based on the opinions of LSF-II operation/maintenance practitioners and PBL experts and the practical experience of this researcher. A survey was conducted on operation/maintenance practitioners and professional personnel. Based on the survey results, the effect of applying PBL was analyzed using the AHP technique, and an efficient PBL application plan was proposed for LSF-II.
        4,000원
        18.
        2023.12 구독 인증기관 무료, 개인회원 유료
        Zhong Hua Zi Jing is Chinese teaching material promoted nationwide and overseas for the purpose of “fast literacy and early reading”, which covers Level 4 Chinese characters specified in the HSK exam outline. Its content includes knowledge of fifty major categories, including astronomy, geography, human relations, history, and the like. Therefore, this study is based on Xu Tongqiang’s sinogram-based theory. This paper proposes a teaching plan using the Zhong Hua Zi Jing in teaching Chinese as a foreign language in order to achieves positive results in vocabulary and Chinese character learning. A survey was first conducted on Korean students in years three and four of the Chinese language major to demonstrate their level of understanding of Chinese characters included in Zhong Hua Zi Jing, and to elucidate the level of understanding of Chinese characters Zhong Hua Zi Jing. Then, the necessity and specific solutions of using Zhong Hua Zi Jing to teach vocabulary mainly based on Chinese characters was explored.
        4,800원
        19.
        2023.12 KCI 등재 구독 인증기관 무료, 개인회원 유료
        Liquified hydrogen is considered a new energy resource to replace conventional fossil fuels due to environmental regulations by the IMO. When building tank for the storage and transportation of liquified hydrogen, materials need to withstand temperatures of -253°C, which is even lower than that of LNG (-163°C). Austenitic stainless steel mainly used to build liquified hydrogen tank. When building the tanks, both the base material and welding zone need to have excellent strength in cryogenic condition, however, manual arc welding has several issues due to prolonged exposure of the base material to high temperatures. Laser welding, which has some benefits like short period of exposure time and decrease of thermal affected zone, is used many industries. In this study, laser bead on plate welding was conducted to determine the laser butt welding conditions for STS 304 and STS 316L steels. After the BOP test, cross-section observations were conducted to measure and compare four bead parameters. These tendency result of laser BOP test can be used as conditions laser butt welding of STS 304 and STS 316L steel.
        4,000원
        20.
        2023.12 KCI 등재 구독 인증기관 무료, 개인회원 유료
        MCCI, one of the ex-vessel phenomena during a severe accident, is generally caused by mutual reactions between molten core and reactor building basemat concrete, but occurs between sacrificial materials made by concrete and corium in APR nuclear power plant with PECS applied. In this paper, MCCI analysis was performed to design and apply a device to block the core melt at the junction connected to the ICI cavity sump from the core catcher installed in the reactor cavity of the APR. Unlike the sacrificial material, which has a cooling effect by inducing erosion of the ex-vessel core melt, the device is composed of concrete applied as a barrier to protect the ICI cavity sump. The decent thickness of the barrier wall of the device was calculated.
        4,000원
        1 2 3 4 5