The purpose of this study is to experimentally analyze the seismic performance of a vertical irregular beam-column specimen reinforced with RBS (Replaceable Steel Brace System), a steel brace system. To evaluate the seismic performance of RBS, three specimens were manufactured and subjected to cycle loading tests. The stiffness ratio of beam-upper column of the non-retrofitted specimen was 1.2, and those of the two retrofitted specimens were 1.2 and 0.84. The stiffness ratio of the beam-lower column of all specimens was 0.36. And the stiffness ratio were used for variable. As a result of the experiment, the specimen retrofitted with RBS showed improved maximum load, effective stiffness and energy dissipation capacity compared to the non-retrofitted specimen with the same beam-upper column stiffness ratio. The specimen with 0.84 beam-upper column stiffness ratio showed improved performance compared to the specimen with 1.2 stiffness ratio.
As the use of shared kickboards rapidly increases, personal mobility (PM)-related accidents are frequently occurring. These accidents are mainly caused by careless behavior, which is typically indicated by neglecting to wear a helmet, speeding, signal violation, or illegal driving owing to incorrect driving methods. This type of user behavior increases the risk of accidents; for this reason, there is an urgent need to prepare effective measures for the safe use of shared kickboards. To reduce PM accidents, this study proposes a charging model that promotes the safe behavior of shared kickboard users. The core aim of this model is to persuade users to comply voluntarily with safety rules through incentives and penalties. Specifically, by providing a discount rate when wearing a helmet, the user is encouraged to wear a helmet, whereas in the event of an accident, a penalty is imposed to emphasize the disadvantages that occur when the safety rules are violated. This incentive structure is expected to contribute to the development of safer driving habits among shared-kickboard users. To verify the effectiveness of this charging model, simulations and user surveys were conducted in parallel. It was found that the user’s safety behavior improved, and the incidence of accidents decreased considerably. This confirmed that the proposed charging model not only reduced accidents but also naturally formed a safe driving culture for users. The shared key proposed in this study can benefit the operating company, and policymakers can contribute in the future by sharing key issues that are expected to play an important role in presentation and punishment, and provide a new paradigm for sharing key paradigms.
Purpose: This study aimed to identify the experiences of career nurses balancing clinical nursing with ongoing studies. Methods: This study was a qualitative study that used the content analysis method. Data were collected using focus group interviews with 17 career nurses with more than 5 years of clinical career at general hospital and above. Results: Six themes and 17 sub-themes were derived through qualitative content analysis. The themes included: “Chose nursing for practical reasons”, “A nurse profession that fits me”, “Seeking personal growth through ongoing studies”, “Practical challenges of being a nurse”, “The attributes that sustain commitment to clinical nursing”, “My future as a nurse”. Conclusion: This study confirmed the the driving force that enables career nurses who are pursuing academic degrees to sustain clinical nursing. The results of this study can be used as useful basic data for the management of career nurses.
In this article, to solve the problems about obsolescence of parts and unable to driving turret when internal components are failure, the DC-DC boost converter in the gun/turret drive system of mobile weapon was improved. The power converting circuit in converter is changed by applying the latest components, and the control circuit is changed from analog to digital. Also, the power converting circuits were modularized in three parallel so that it could be driven even when some components failed. The improved DC-DC boost converter secured stability such as converting to voltage in a linear manner in the entire section from the start of boosting to the end. Also, through the modular configuration, turret driving system can operates when some components failed.
Advanced technoloigy, according to the development of science, is also applied to weapons systems to prepare for future battles. But the emergence of new technologies leads to DMSMS(Diminishing Manufacturing Source and Material Shortage) because it brings a short life cycle of parts. In particular, DMSMS frequently appear in electronic parts with a short launch cycle for new products. The life support system of K2MBT(Main Battle Tank) is a key functional item related to crew survivability and convenience. Recently, various parts have been cut off on the life support system, requiring a redesign of the Control Box. The K2MBT is not only central to domestic production but also plays a key role in export projects to countries like Poland, making continuous production necessary. This study aimed to ensure the sustainability of component production and reduce maintenance costs by redesigning the control box.
Silicon-based anode materials have attracted significant interest because of their advantages, including high theoretical specific capacity (~4,200 mAh/g), low working potential (0.4 V vs Li/Li+), and abundant sources. However, their significant initial capacity loss and large volume changes during cycling impede the application of silicon-based anodes in lithium-ion batteries. In this work, we propose a silicon oxide (SiOx) anode material for lithium-ion batteries produced with a magnesio-thermic reduction (MTR) process adopting Boryeong mud as a starting material. Boryeong mud contains various minerals such as clinochlore [(Mg,Fe)6(Si,Al)4O10(OH)8], anorthite (CaAl2Si2O8), illite [K0.7Al2(Si,Al)4O10(OH)2], and quartz (SiO2). The MTR process with Boryeong mud generates a mixture of amorphous silicon oxides (SiOx and SiO2), and magnesium aluminate which helps to alleviate the volume expansion of the electrode during charge/discharge. To observe the effects of these oxides, we conducted various analyses including X-ray diffraction (XRD), scanning electron microscopy (SEM), Fourier-Transformation infrared spectroscopy (FT-IR), Brunauer-Emmett-Teller (BET) and cyclic voltammetry (CV) galvanic cell testing. The amorphous SiO2 and MgAl2O4 suppressed the volume expansion of the silicon-based anode, and excellent cycle performance was achieved as a result.
PURPOSES : Recently, interest in radioactive accidents has increased due to domestic and international nuclear power plant accidents. In particular, local residents' concerns are increasing due to safety issues such as radioactive leaks at the Hanbit Nuclear Power Plant in South Korea. As Gwangju Metropolitan City is not included in the emergency planning area set by the Nuclear Safety and Security Commission, there are significant limitations to establishing disaster prevention measures for nuclear power plant accidents. Considering the Fukushima and Hanbit nuclear power plant accidents, the improvement of Gwangju Metropolitan City's radioactive leak accident response manual is urgently required. This study aimed to establish disaster prevention measures to respond to nuclear power plant accidents in Gwangju Metropolitan City in the event of a Hanbit Nuclear Power Plant accident and to improve resident protection measures by estimating the arrival time of radioactive materials and radiation dosage through a nuclear power plant accident simulation. Additionally, we aimed to supplement the on-site action manual for radioactive leaks at the Hanbit Nuclear Power Plant. METHODS : This study focused on establishing disaster prevention measures centered on Gwangju Metropolitan City in the event of a major accident such as a radioactive leak at the Hanbit Nuclear Power Plant. Simulations were conducted assuming a major accident such as a radioactive leak, measures to improve resident protection were established by calculating the arrival time of radioactive materials and radiation dosage in the Gwangju area in the event of a nuclear power plant accident, and on-site response action manuals were supplemented in response to a radioactive leak. RESULTS : This study considered the concerns of local residents due to the Fukushima nuclear power plant accident and the Hanbit nuclear power plant failure, conducted a simulation to derive the impact on Gwangju Metropolitan City, and examined the effectiveness of an on-site response manual for radioactive leaks to derive improvement measures. CONCLUSIONS : In the event of an accident at the Hanbit Nuclear Power Plant in Gwangju Metropolitan City, insufficient portions of the on-site response action manual should be supplemented, and close cooperation with local governments within the emergency planning area should be ensured to respond to radioactive disasters. Therefore, based on the revised on-site response action manual for radioactive leaks, close cooperation and a clear division of roles among local governments will enable effective resident protection measures to be implemented in the event of a radioactive disaster.
본 연구는 경상남도 지역 내 치유농장 운영 실태를 조사하여 향후 경남지역에 적합한 치유농장 운영과 프로그램 개발을 위한 기초 자료를 제공하기 위해 수행되었다. 조사 결과, 37개 치유농장 중 62.1%는 기존에 교육농장, 사회적 농업 거점농장, 농가 맛집, 체험농장 등으로 운영되다가 3년 전부터 치유농업을 도입하여 현재 다양한 형태로 운영되고 있는 것으로 나타났다. 치유농장 시설의 경우, 숙박시설이 있는 농가는 40.5%, 예약제로만 운영되는 농가는 59.5%, 장애인을 위한 편의시설이 마련된 농가는 48.6%로 나타났다. 또한, 응급 처치 및 안전 관련 용품은 100%의 농가에서 비치하고 있었고, 치유농장 홍보는 SNS와 온라인을 이용하는 농가가 84.1%로 가장 많았다. 예방 중심형 치유 프로그램을 운영하는 농가는 76.2%였고, 개인보다 단체 참여 비율이 86.3%로 높게 나타났다. 치유 프로그램 운영자는 치유농업사 양성기관 교육을 이수하거나 치유농업 시설 운영자 교육 이수자 또는 치유농업사 자격 소지의 농장 경영주가 59.6%로 가장 많았으며, 1회당 참여 인원은 11명에서 20명까지가 43.2%, 1회당 운영 시간은 120분이 51.4%, 참가 비용은 1만원에서 3만원까지가 71.3%로 가장 많은 비중을 차지했다. 활용 자원으로는 식물 자원이 48.6%, 농촌 환경 문화 자원이 39.2%, 동물 및 곤충 자원이 12.2%로 나타났다. 프로그램 운영에 있어 치유농장 운영자의 전문성은 4.48점으로 가장 높았고, 치유농장 자원 중 환경 자원은 4.37점, 편의시설은 쾌적하고 청결한 환경 4.13점, 기타 부가서비스는 농장의 신뢰성이 4.45점으로 가장 중요한 요소로 평가되었다. 효율적인 치유농장 운영에 있어 치유농장 운영자의 전문성, 친밀감·편안한 분위기, 자연경관, 편안하고 안락한 시설, 농장의 신뢰성 요소는 서로 상관관계(p<.05)가 있는 것으로 나타났다.
본 연구는 애니매이션 『진격의 거인』 속 관계들을 프로이트의 구조적 관점을 통하여 21세기 현재 우리 나라에서 보여지는 MZ세대의 특징과 연결해보고자 하였다. 연구 결과 첫째, 이드 충동으로써의 에렌은 현재의 만족만을 추구하는 MZ세대의 부정적 측면으로 나타나므로 계획하고 조 절할 수 있는 자아의 능력이 필요하다. 둘째, 박해적 초자아로써의 마레 는 MZ세대의 부모의 욕구에 동일시 되는 것으로 나타나므로 무의식적 죄책감이 자극된 초자아의 형성이 아닌 긍정적 초자아의 형성이 필요하 다. 셋째, 마비된 자아로써의 벽 안 인류는 MZ세대의 기본적인 욕구를 포기하는 것으로 나타나므로 이드 충동의 추구가 아니라 초자아를 완화 하고 자아를 강화하는 것이 필요하다. 따라서 MZ세대는 자아를 강화하 기 위해 자신이 진정으로 원하는 것과 할 수 있는 것이 무엇인지를 찾아 야 하며 사회는 MZ세대를 이해하는 관심을 통하여 성숙하고 성장하여야 한다.
The main hydraulic pump is a device that generates the hydraulic pressure needed for the K2 tank. It is a pressure-compensated swash plate piston pump that generates the hydraulic power necessary to drive the hydraulic device. Hydraulic pump design changes were made due to frequent failures of the hydraulic pump. As a result of checking the operation records of the hydraulic pump, about 71% of the total engine operation time was in a stationary state where hydraulic pressure was not needed. This has the problem of constantly running when the engine is started, consuming unnecessary endurance time, and generating high noise. In this study, ISG(Idle Stop & Go) was applied to improve operation method. When applying ISG, the pressure can be reduced to about 85% or less in an environment where the operation of the main hydraulic pump is not necessary. So, the lifespan of the main hydraulic pump increases as a result of ISG application, thereby reducing the waste of national funds due to maintenance costs. Also, it is expected to contribute to improving combat power by reducing crew fatigue due to noise reduction.
Obesity, a global health concern characterized by excessive fat accumulation, necessitates the discovery of anti-obesity compounds. Rottlerin, known for its anti-cancer effects as a mitochondrial uncoupler, has been a subject of interest. However, its impact on reducing intracellular lipid accumulation remains a gap in our understanding. This study aimed to fill this gap by dissecting the mechanism of rottlerin in 3T3-L1 adipocytes. We treated differentiated 3T3-L1 cells with 0-20 mM of rottlerin for 48 hours to assess its capability to induce lipid accumulation. Notably, we observed no cytotoxicity associated with the treatment of rottlerin up to 20 mM, indicating its safety at these concentrations. Lipid accumulation, measured by oil Red O, was downregulated dose-independently by rottlerin. We also found that key lipogenic enzymes, including SCD1 and DGAT1, were decreased. The transcription factor of lipogenic genes, SREBP1, was reduced by approximately 80% with rottlerin. LRP6, a crucial link between de novo lipogenesis mechanism reactions and Wnt signaling, was also degraded by around 70%. Interestingly, the downstream regulation of LRP6, b-catenin, and TCFL2 was diminished by rottlerin. Our data indicate that rottlerin alleviates adipocyte lipid accumulation by suppressing the LRP6/β-catenin/SREBP1c pathway. These findings underscore the potential of rottlerin as a safe nutraceutical for combating obesity.
This study evaluated the changes in the quality characteristics of extracts (Quantum Energy) from Rehmannia glutinosa, ginseng, balloonflower, Poria cocos, and Adenophora stricta. The extracts were prepared through a six-day aging process, during which the pH decreased with a longer aging period while the viscosity and oBrix values were increased. The color difference (E) of the extracts ranged from 0.27 to 0.49 for all samples, indicating minimal color change with aging. The free sugar content was highest for fructose and glucose, while lactose was not detected. Furthermore, the total free sugar content ranged from 24.518 to 27.646 g/100 g, generally decreasing with the aging time. Benzo[a]pyrene in the extracts ranged from 0.040 to 0.074 g/kg, which is below the limit of quantification. In addition, all extracts were free of total aerobic bacteria, Escherichia coli, and coliforms, confirming that the aging method used in this study was microbiologically safe.
본 연구에서는 서울 북부지역에서 유통된 1,737건의 농 산물을 대상으로 잔류농약 실태 조사 및 위해성 평가를 하였다. 분석 시료는 QuEChERS 법으로 전처리한 후 GCMS/ MS 및 LC-MS/MS를 이용하여 분석하였으며, 다빈도 부적합 성분을 대상으로 직선성과 정량한계, 회수율, 상대 표준편차(RSD%) 구한 결과 OECD 및 Codex의 기준에 적 합하였다. 또한 모니터링 결과 72품목 560건(32.2%)에서 잔류농약이 검출되었으며 22품목 38건(2.2%)이 잔류농약 허 용치를 초과하였다. 잔류농약이 많이 검출된 품목은 과일류 53.8%, 채소류 33.0%, 허브류 28.6%, 두류 15.4%, 곡류가 10.5% 순이였으며, 잔류농약 허용치를 초과한 품목은 채소 류 중 엽채류, 엽경채류, 근채류, 향신료 및 버섯 등이었다. 검출된 농약은 105종으로 그 중, dinotefuran, fluxametamide, chlorfenapyr, azoxystrobin, carbendazim이 가장 많이 검출되 었으며, terbufos, carbendazim, fluxametamide 등 23종의 성 분에서 잔류 허용기준이 초과되었다. 잔류허용기준을 초 과한 농약에 대해 위해 평가를 수행한 결과 위해 지수가 0.00003-1.31406%로 매우 낮은 수준으로 산출되어 안전한 것으로 평가되었다.
본 연구에서는 경기 북부지역 및 온라인에서 유통되는 건고추 및 고춧가루 88건을 대상으로 잔류농약을 분석했 다. 시료는 QuEChERS법으로 전처리한 후 GC-MS/MS, LC-MS/MS를 이용하여 분석했다. 88건 중 70건(79.5%)에 서 잔류농약이 검출되었고 그 중 4건(4.5%)인 수입산 건 고추 2건, 수입산 고춧가루 2건이 농약 잔류허용기준을 초 과하였다. 총 61종의 농약이 검출되었고 검출 빈도가 가 장 높은 농약은 살균제 tebuconazole로 52회 검출되었다. 쌀에 사용하는 진균제 tricyclazole은 베트남산 시료 12개 중 3개 시료에서, ethion은 인도산 시료 1개에서 농약 잔 류허용기준을 초과하여 검출되었다. tricyclazole과 ethion 은 고추 품목에서의 사용이 금지되어 positive list system 제도에 의해 규제되고 있다. 본 연구를 통해 국내산 건고 추 및 고춧가루의 잔류농약 수준이 비교적 잘 관리되고 있으며 수입산 건고추 및 고춧가루에 대한 지속적인 관리 가 필요한 것으로 확인하였다.
Scientific exploration of how occupational health risks relate with occupational illnesses are essential for mitigating health-related issues in industries. This study analyzed the risk scores obtained by occupational health risk assessments at 3,172 manufacturing companies and examined their effects on occupational illness. Statistical analyses revealed that companies with an occupational health manager (scored 89.1 out of 100) had significantly higher activity scores of health management compared to those without (78.2). However, companies with a history of occupational illness (79.1) or those classified as high-risk industries (85.2) had significantly lower activity scores than their counterparts (81.7, 87.3). In addition, regression analyses using factor analysis showed that latent risk factors such as cardiovascular disease/job stress, health management, and musculoskeletal problem significantly influenced the risk of occupational illness. The activity factors such as health management, work environment management, and regulatory complaisance significant impacted the reduction of occupational illness. The findings of this study can be used to improve the occupational health risk assessment method and utilized in effectively managing occupational risks in industries.
이 연구는 전기고령여성의 화장품 사용실태 및 요구도에 따른 노인화장 품의 필요성에 대해 검증하고자 하였다. 이 연구는 서울 및 지방도시 지역 에 거주하는 60세 이상의 전기고령 여성을 대상으로 2023년 12월 23일부 터 2024년 1월 16일까지 최종 286부를 SPSS 25.0 프로그램을 활용하 였다. 분석결과, 전기고령 여성은 자신의 스타일과 피부에 맞는 제품을 찾 기 위해 개인적으로 화장품을 선택하고 구매하는 경향을 보였고, 피부 건강 과 미용에 대한 관심이 높았으며, 피부 탄력과 주름 개선에 초점을 맞춘 제품을 선호하는 것으로 나타났다. 또한, 화장품의 촉촉함과 무향성을 중요 시하며, 특히 주름 개선 기능이 있는 아이크림에 대한 수요가 높았다. 제품 의 용량과 가격을 고려하는 것이 중요한 경제적 요인으로 작용했으며, 화장 품의 디자인으로 심플함과 쉬운 개폐 구조를 선호하는 것으로 나타났다. 이상의 연구결과에서, 노인화장품은 피부 건강과 미용에 대한 전기고령 여 성들의 요구를 충족시키고, 경제적으로 적정한 가격대의 노인화장품을 개발하 고 보급한다면, 전기고령 여성들의 삶의 질 향상에 기여할 것으로 예상된다.