친환경 폴리우레탄은 다양한 분야에서 다양하게 사용되는 활용성이 높은 소재로 정의 할 수 있다. 이소시아네이트와 폴리올의 합성에 따른 다양한 구조적 특성 관계는 제조현장에서 사용상의 다양 성과 맞춤화를 제공하고 있다. 폴리우레탄의 특성은 부드러운 터치 코팅부터 바위처럼 단단한 건축 자재 에 이르기까지 활용 범위가 매우 다양하다. 이러한 기계적, 화학적 및 생물학적 특성과 맞춤의 용이성은 연구분야에서 뿐만 아니라 관련 산업에서도 엄청난 관심을 불러오고 있다. 수분산 폴리우레탄 재료의 성 능향상을 높이기 위해서는 원료의 배합을 조정하고 첨가제와 나노 소재등을 추가하는 등의 과정을 통해 이끌어 낼 수 있다. 본 연구에서는 의료 과학, 자동차, 코팅, 접착제, 페인트, 섬유, 해양 산업, 목재 복 합 재료 및 의류분야의 친환경 수분산 폴리우레탄 기본 화학 구조를 조명한다.
본 연구에서는 학습자들의 VR에 대한 의식을 바탕으로 VR을 활용한 피부미용 교과목 개발을 위한 교육환경을 확보하고자, 총 105명의 학습자들의 VR에 대한 인식, VR의 체험요소, VR활용 피부미용 교과목 개발 인식, 일반적 특성에 관한 문항을 온라인 설문지를 이용하여 진행하였다. 빈도분석, 요인분석, 상관관계 분석을 통한 조사결과, VR에 대한 인지도가 높을수록 교육적 성과와 몰입도가 높을 것으로 (p<.01), 학력이 높을수록 VR 활용 피부미용 체험요소인 일탈성, 인지성, 관심도가 높은 것으로 나타났다 (p<.001). 상관관계에서는 VR이용 스킨케어 경험요인이 높을수록 VR 활용 피부미용 교과목 개발 인식이 높은 것으로 나타났다. 따라서 학습자의 기대와 4차 산업혁명 시대에 부합하는 VR을 활용한 피부미용 교 과목 개발과 교육이 빠르게 운영될 필요가 있음을 확인하였다. 이에 후속 연구에서는 VR 활용 피부미용 교과목 개발과 운영 후의 연구 진행이 필요할 것으로 사료된다.
본 논문에서는 중심가새골조의 내진성능 향상을 위한 전단항복 댐퍼의 개발을 수행하였다. 실용성이 높은 댐퍼의 개발을 위해서 구조적 간결성과 내진성능의 신뢰도에 중점을 둔 상세를 제시하기 위해 노력하였다. 지진 발생 시 에너지 소산 메커니즘에 대한 신뢰 도가 높고, 지진 발생 후 항복 부위의 교체가 쉬운 형태로 고안되었다. 댐퍼의 끼움강판 치수를 변경함으로써 전단, 휨-전단, 휨 메커니 즘을 조절하여 설계할 수 있다. 비선형 유한요소해석을 통해서 댐퍼의 항복 메커니즘에 따른 구조적 거동을 분석하였고, 전단항복 메 커니즘 댐퍼가 휨항복 메커니즘 댐퍼에 비해 강성, 강도, 에너지 소산 측면에서 우수한 성능을 가지고 있음을 확인하였다.
In this study, indoor air quality indices (IAQI-C and IAQI-E) were developed for child care centers and elderly care centers based on health effects, and compared to the air quality index (CAI) for outdoor atmosphere. In addition, composite indices that integrate individual indices for each pollutant were developed to quickly and conveniently recognize the current air quality. Among all data, 71.2% and 35.6% belonged to the grades 'Good' and 'Moderate' for child care centers and elderly care centers, respectively. This assessment is more stringent than the CAI's criteria.
A pump-type eDNA filtering system that can control voltage and hydraulic pressure respectively has been developed, and applied a filter case that can filter out without damaging the filter. The filtering performance of the developed system was evaluated by comparing the eDNA concentration with the conventional vacuum-pressured filtering method at the catchment conduit intake reservoir. The developed system was divided into a voltage control (manual pump system) method and a pressure control (automatic pump system) method, and the pressure was measured during filtering and the pressure change of each system was compared. The voltage control method started with 65 [KPa] at the beginning of the filtering, and as the filtering time elapsed, the amount of filtrate accumulated in the filter increased, so the pressure gradually increased. As a result of controlling the pressure control method to maintain a constant pressure according to the designed algorithm, there was a difference in the width of the hydraulic pressure fluctuation during the filtering process according to the feedback time of the hydraulic pressure sensor, and it was confirmed that the pressure was converged to the target pressure. The filtering performance of the developed system was confirmed by measuring the eDNA concentration and comparing the voltage control method and the hydraulic control method with the control group. The voltage control method obtained similar results to the control group, but the hydraulic control method showed lower results than the control group. It is considered that the low eDNA concentration in the hydraulic control method is due to the large pressure deviation during filtering and maintaining a constant pressure during the filtering process. Therefore, rather than maintaining a constant pressure during filtering, it was confirmed that a voltage control method in which the pressure is gradually increased as the filtrate increases with the lapse of filtering time is suitable for collecting eDNA. As a result of comparing the average concentration of eDNA in lentic zone and lotic zone as a control group, it was found to be 96.2 [ng μL-1] and 88.4 [ng μL-1l], respectively. The result of comparing the average concentration of eDNA by the pump method was also high in the lentic zone sample as 90.7 [ng μL-1] and 74.8 [ng μL-1] in the lentic zone and the lotic zone, respectively. The high eDNA concentration in the lentic zone is thought to be due to the influence of microorganisms including the remaining eDNA.
Intertidal mud crab (Macrophthalmus japonicus) is an organism with a hard chitinous exoskeleton and has function for an osmotic control in response to the salinity gradient of seawater. Crustacean exoskeletons change in their natural state in response to environmental factors, such as changes in the pH and water temperature, and the presence of pollutant substances and pathogen infection. In this study, the ecotoxicological effects of irgarol exposure and heavy metal distribution were presented by analyzing the surface roughness of the crab exoskeleton. The exoskeleton surface roughness and variation reduced in M. japonicus exposed to irgarol. In addition, it was confirmed that the surface roughness and variation were changed in the field M. japonicus crab according to the distribution of toxic heavy metals (Cd, Pb, Hg) in marine sediments. This change in the surface roughness of the exoskeleton represents a new end-point of the biological response of the crab according to external environmental stressors. This suggests that it may affect the functional aspects of exoskeleton protection, support, and transport. This approach can be utilized as a useful method for monitoring the aquatic environment as an integrated technology of mechanical engineering and biology.
본 논문에서는 국내 최초로 건축구조기준(KBC 2016)에 기반하여 확률적 영역에서 초과손상확률 형태와 평균손상확률 형태 의 강풍 취약도 평가 방법론을 개발하였다. 본 연구에서는 풍하중에 대한 3초 순간풍속의 영향을 고려할 수 있는 풍하중 산정식을 건 축구조기준을 기초로 유도하였다. 또한 풍하중과 관련된 문헌을 기초로 유도된 3초 순간풍속 기반의 풍하중 산정식에 적용할 수 있는 풍하중 산정계수의 통계치를 제시하였다. 본 연구에서는 초과손상확률 형태와 평균손상확률 형태의 강풍 취약도를 평가하기 위하여 몬테카를로 모사(Monte Carlo Simulation) 기법을 이용하여 해석적 확률 모델을 개발하였다. 제안한 강풍 취약도 평가 방법론의 신뢰 성은 저층 건축물 모형의 지붕 쉬딩 패널 시스템(roof sheathing panel system)을 대상으로 ASCE(American Society of Civil Engineers) 풍하중 기준을 적용한 취약도 평가 방법론의 결과와 비교·검증되었다. 본 연구는 국내 건축구조기준의 풍하중 산정식을 이용하여 강 풍 취약도의 평가 방법론을 보이며, 제안된 방법론에 의한 강풍 취약도는 기존 ASCE 기반 방법론의 결과와 비교하여 작은 오차 범위 내에서 잘 일치함이 확인되었다. 본 연구에서 제시한 강풍 취약도 평가 방법론은 자연재해저감계획 등에 따른 강풍 피해 예측 시 취약 도 구축 방법으로 적용될 수 있을 것으로 판단된다.
본 연구의 목적은 마우스 사용 시 손목터널증후군을 예방할 수 있는 스마트장갑을 연구하는 것이다. 연구에 앞서 손목의 좌·우 움직임은 미세하므로 게이지율(Gauge Factor)이 크고, 이력현상(Hysteresis)이 적은 인장 직물 센서가 필요하다. 만능재료시험기(UTM)를 통해 4가지의 직물을 분석하여 각각의 게이지율을 계산하고, 이력현상도 가장 적은 직물을 선택하였다. 또한, 3가지 부착방법을 아두이노로 분석하여 센서값 변화(△Sensor Value) 값이 큰 방법을 선택하였다. 선택된 직물과 부착방법으로 제작한 프로토타입을 아두이노를 통해 데이터 패턴을 분석하였다. 첫 번째 는 센서 1개(A 센서)로만 파악하는 방법이고, 두 번째로는 센서 2개(A, B 센서)로 파악하는 방법이다. 손목 왼쪽(A 센서), 손목 오른쪽(B 센서) 양쪽에 인장 직물 센서를 부착하고, 손목을 오른쪽으로 꺾을 때 A 센서는 늘어나서 △ Sensor Value 값이 커지고, B 센서는 줄어들어서 △Sensor Value가 작아진다. 반면에 손목을 왼쪽으로 꺾을 때는반대로 패턴이 분석되었다. 본 연구를 통해 손목이 꺾일 시 LED가 켜지는 알고리즘으로 손목터널증후군을 예방하는 스마트장갑을 연구하였고, 본 연구 결과를 기반으로 후속 연구에서는 10명을 대상으로 직접 마우스를 사용하면서 실제 사용 시 문제점을 파악하고 파악된 문제점을 해결하고자 한다.
수산업은 수산물의 남획, 국가 간의 제한, 기후변화로 인하여 수산물 개체 수 감소 등으로 전 세계 수산물 생산량이 정체되면서, 양식업은 항상 세계 식량 소비를 위해 오랫동안 지속되어 온 패러다임을 뒤집고 인류가 바다, 호수, 강의 풍부함을 새로운 방식으로 확장할 수 있도록 하는 '푸른 혁명'의 가능성을 제시하고 있다. 양식산업은 이제 인간 소비를 위한 해산물의 원료 로서 해양에서 얻는 어업생산량의 절반이상을 넘어섰다. 지속 가능한 양식산업의 발전을 위하 여 다양한 최신 생물학적 연구 방법들이 적용되고 있다. 유전체학은 2011년 대서양 대구의 염 기서열이 규명된 이래 최근 상당한 진전을 이루었으며 더 많은 종의 유전체가 해독되어 우수 형질의 육종 및 번식 기술, 질병 저항성 품질 개량, 양식 사료 및 사료방식의 최적화 등 양식산 업을 위한 보다 견고하고 생산적인 지식 기반을 제공한다. 본 리뷰는 수산양식종의 유전체 연 구를 위한 유전체 분석 기술과 수산양식종의 유전체 연구의 현황에 대해서 살펴보았다. 이와 같이 유전체 분석 기술과 유전체학의 발전은 수산양식산업의 과제를 해결하는 데 중요하며 지속 가능한 어업과 양식에 도움을 줄 것이다.
Purpose: This study aimed to develop a web-based video program related to abnormal mental disorder behaviors in standardized patients and verify its effectiveness for nursing students. Methods: This study consisted of pre-test and post-test for a non-equivalent control group design. The participants were 46 nursing students(experimental group: 23, control group: 23). The experimental group was trained in a video program that applied standardized patients, while the control group received traditional training. Data collected from March to June, 2020, were analyzed using IBM SPSS Statistics for Windows, version 25.0, chi-square test, Fisher's exact test, Mann-Whitney U test, and independent t-test. Results: The difference between the experimental and control groups was statistically significant in terms of learning satisfaction (Z=2.08, p=.038), learning self-efficacy(t=2.80, p=.009), motivation for transfer(t=3.45, p=.001), and clinical reasoning competence(t=2.28, p=.028). Conclusion: This study showed that a video program on abnormal mental disorder behaviors in standardized patients is an effective tool for mental health nursing education.
The aim of this study was to develop a body type suitable for adult men aged from their 20s to their 40s and to present a method of drafting related patterns. To this end, the somatic surface pattern data from previous studies were used. The research method involved drafting torso patterns for each type by setting and distributing the ease to the somatic surface pattern. Appearance evaluation was performed with virtual clothing. Then, the torso pattern for each body type was completed and presented as a draft method. SPSS was used for data analysis in this study. The research results are as follows. Types 1, 2, and 3 were set to 7%, 6%, 5%; 7%, 6%, 4%; and 6.5%, 7%, and 6% for chest, waist, and hip circumference measurements, respectively. The ratio of front to back was 50%:50%, 50%:50%, and 50%:50% of the spare for each body part for Type 1; 70%:30%, 50%:50%, and 60%:40% for Type 2, and 60%:40%, 70%:30%, and 60%:40% for Type 3. A tight-fit torso pattern for each body type suitable for adult males in their 20s to 40s was drafted, which was modified and supplemented through the evaluation of the first and second virtual wear. Considering the practicality of this approach, for generalization of the patterns, the items of the pattern were converted into a drafting method and presented as a draft method.
The purpose of this study was to examine the current satisfaction levels with nurse uniforms at Taizhou General Hospital in China and to find areas for improvement in order to develop nurse uniforms with improved comfort, fit and convenience. To investigate satisfaction with nurse uniforms, a survey was conducted of 150 nurses. The general characteristics of the nurses, uniform conditions, feelings of satisfaction, fit, preferred designs, inconvenient aspects of the uniforms, and areas for improvement were analyzed. Eight materials of cotton/polyester blended fabrics were selected according to Chinese nurse uniform regulations, and the physical properties of the materials were tested along with the materials used in current nurse uniforms. Four new nurse uniforms with increased aesthetics, functionality, and comfort were developed based on the survey results. Materials with excellent absorption, moisture permeability, and ventilation were used as main fabrics. According to the preferred designs of nurses at Taizhou City General Hospital, China, 4 types of nurse uniforms designed, consisting of design 1 (shirt and pants), design 2 (shirt and pants), design 3 (dress), and design 4 (shirt and skirt). The new nurse uniforms offered better functionality with an improved fit at the armpits, waist, hips, and knees based on product measurements.
1. 본 연구는 한국-미얀마 농업분야 개발협력(ODA)의 지속 가능성 강화 방안을 분석하기 위해 2001~2017년 시계열(time series)자료를 토대로 자기회귀분포시차 모델(Autoregressive Distributed Lag, ARDL)방법과 최소자승법(Ordinary Least Square, OLS)을 사용하였다. 2. 분석결과 1) 미얀마 농업 개발에 지원된 국제사회의 ODA, 한국이 지원한 농업 분야 ODA, 농촌 개발에 대한 한국 ODA 등의 변수가 미얀마의 농업 GDP에 긍정적으로 기여한 반면, 2) 한국 ODA는 가치사슬 분야 및 기술전수 분야에 미친 영향이 부정적으로 나타났다. 이는 이 분야의 지원 규모가 매우 작아 미얀마 농업발전에 미친 영향을 측정하기 어렵기 때문인 것으로 해석할 수 있다. 또한 한국이 미얀마에 제공한 농업 ODA 중 농산물 생산 및 유통 분야에 대한 지 원은 영향이 미미한 것으로 나타났으나 양(+)의 영향을 나타 내었다. 3. 분석 결과 한국의 미얀마 대상 농업 분야 ODA는 선택과 집중을 토대로 미얀마 농업 발전에 긍정적인 영향을 미치고 있는 농촌개발 분야에 장기적으로 지원을 확대할 필요성이 있음을 확인하였다.
As Deepfakes phenomenon is spreading worldwide mainly through videos in web platforms and it is urgent to address the issue on time. More recently, researchers have extensively discussed deepfake video datasets. However, it has been pointed out that the existing Deepfake datasets do not properly reflect the potential threat and realism due to various limitations. Although there is a need for research that establishes an agreed-upon concept for high-quality datasets or suggests evaluation criterion, there are still handful studies which examined it to-date. Therefore, this study focused on the development of the evaluation criterion for the Deepfake video dataset. In this study, the fitness of the Deepfake dataset was presented and evaluation criterions were derived through the review of previous studies. AHP structuralization and analysis were performed to advance the evaluation criterion. The results showed that Facial Expression, Validation, and Data Characteristics are important determinants of data quality. This is interpreted as a result that reflects the importance of minimizing defects and presenting results based on scientific methods when evaluating quality. This study has implications in that it suggests the fitness and evaluation criterion of the Deepfake dataset. Since the evaluation criterion presented in this study was derived based on the items considered in previous studies, it is thought that all evaluation criterions will be effective for quality improvement. It is also expected to be used as criteria for selecting an appropriate deefake dataset or as a reference for designing a Deepfake data benchmark. This study could not apply the presented evaluation criterion to existing Deepfake datasets. In future research, the proposed evaluation criterion will be applied to existing datasets to evaluate the strengths and weaknesses of each dataset, and to consider what implications there will be when used in Deepfake research.
This study aimed to develop strain-specific polymerase chain reaction (PCR) primers to detect Fusobacterium hwasookii KCOM 1249T, F. hwasookii KCOM 1253, F. hwasookii KCOM 1256, F. hwasookii KCOM 1258, and F. hwasookii KCOM 1268 on the basis of nucleotide sequences of a gene specific to each strain. The unique genes for each F. hwasookii strain were determined on the basis of their genome sequences using Roary. The strain-specific PCR primers based on each strain-specific gene were designed using PrimerSelect. The specificity of each PCR primer was determined using the genomic DNA of the 5 F. hwasookii strains and 25 strains of oral bacterial species. The detection limit and sensitivity of each strain-specific PCR primer pair were determined using the genomic DNA of each target strain. The results showed that the strain-specific PCR primers correspond to F. hwasookii KCOM 1249T, F. hwasookii KCOM 1253, F. hwasookii KCOM 1258, F. hwasookii KCOM 1256/F. nucleatum subsp. polymorphum KCOM 1260, or F. hwasookii KCOM 1268/Fusobacterium sp. oral taxon 203 were developed. The detection limits of these strain-specific PCR primers ranged from 0.2 to 2 ng of genomic DNA for each target strain. The results suggest that these strain-specific PCR primers are valuable in quality control for detecting specific F. hwasookii strains.
Automated Guided Vehicle (AGV) is commonly used in manufacturing plant, warehouse, distribution center, and terminal. AGV is self-driven vehicle used to transport material between workstations in the shop floor without the help of an operator, and AGV includes a material transfer system located on the top and driving system at the bottom to move the vehicle as desired. For navigation, AGV mostly uses lane paths, signal paths or signal beacons. Various predominant sensors are also used in the AGV. However, in the conventional AGV, there is a problem of not turning or damaging nearby objects or AGV in a narrow space. In this paper, a new driving system is proposed to move the vehicle in a narrow space. In the proposed driving system, two sets of the combined steering-drive unit are adopted to solve the above problem. A prototype of AGV with the new driving system is developed for the comparative analysis with the conventional AGV. In addition, the experimental result shows the improved performance of the new driving system in the maximum speed, braking distance and positioning precision tests.
This paper is to study the technology of inspection and history management systems for wind power that are continuously increasing around the world. In the past, inspections and analysis of major devices in renewable energy system have been operated in an analog way that identifies problems through photography and passive method. To improve this problem, we conduct a study on VR-based inspection history management system using 3D texturing technique of drone image. The paper describes the current status and prospects of wind power, research and development of wind power blade inspection and history management systems, experiments and reviews in the field, and expected effects and future utilization of this technology. It is expected that the latest technology for inspection and management of renewable system will be secured and introduced to the site through the development research of this system to reduce maintenance costs and power generation costs.
The efficient nutrient solution cooling system consisting of buffer tank, three-way valve, and heat pump et al. was developed for hydroponics of leafy vegetables at high temperatures period. It was designed in such a way that the buffer tank was first cooled to enable precise temperature control of the nutrient solution with small capacity heat pump. Developed system was installed in the NFT hydroponics farm cultivating leafy vegetables and performance evaluation was carried out. For cultivation of Lalique lettuce(Lactuca sativa var.), the temperature of nutrient solution tank, buffer tank, and the root zone, the performance of cooling system, and the environment of greenhouse were analyzed. Also, by measuring the growth and yield of lettuce, the effect of cooling nutrient solution on the growth of lettuce NFT hydroponics was analyzed.
Gas springs applied to various industrial fields are generally composed of a cylinder, a piston rod, a cover, and a seal mount. Because of the thin wall of the cylinder, small gas springs are manufactured using a roller forming process that presses the cylinder wall into a groove of cover in the cylinder. In this study, finite element analysis and process design of roller forming are performed to systematically manufacture the small gas spring and develop a roller forming machine. In order to perform roller forming analysis, tensile tests of structural steel pipe are performed and mechanical properties are analyzed. Roller forming process parameters such as radius and depth of roller grooves are derived using the incompressible condition of plastic deformation theory and the results of finite element roller forming analysis. Using the derived roller shape, a roller forming machine is developed and prototypes of the small gas spring are manufactured. Finally, the dimensional accuracy of the manufactured gas spring prototypes is analyzed through three-dimensional shape measurement.
This study was to develop a piston rod made of SiC by applying a sintering treatment after press molding in order to replace the imported piston rod used in the past. As a result of evaluating the mechanical properties of the developed piston rod, the following conclusions were obtained. The surface roughness value of the piston rod made of silicon carbide was 0.950Ra, and the surface Vickers hardness value was 19.94GPa. As a result of XRD analysis of the surface of the prototype piston rod, the main crystalline phase was 6H-SiC, and the crystalline phases of 4H-SiC and α-SiC were existed. In addition, a trace amount of SiC was detected. As a result of SEM observation of the piston rod surface of the prototype, a number of large porosity were observed. As a result of measuring the surface hardness of the piston rod made of SiC, it showed 70% of the physical properties compared to imported products.