This study aimed to investigate the difference that convolutional neural network(CNN) shows in the determining osteoporosis on panoramic radiograph by performing a paired test by inputting the original image and the limited image including the cortical bone of the posterior border of the mandible used by radiologists. On panoramic radiographs of a total of 661 subjects (mean age 66.3 years ± 11.42), the area including the cortical bone of the posterior part of the mandible was divided into the left and right sides, and the ROI was set, and the remaining area was masked in black to form the limited image. For training of VGG-16, panoramic radiographs of 243 osteoporosis subjects (mean age 72.67 years ± 7.97) and 222 normal subjects (mean age 53.21 years ± 2.46) were used, and testing 1 and testing 2 were performed on the original and limited images, respectively, using panoramic radiographs of 51 osteoporosis subjects (mean age 72.78 years ± 8.3) and 47 normal subjects (mean age 53.32 years ± 2.81). The accuracy of VGG-16 for determining osteoporosis was 97%, in the testing 1 and 100% in the testing 2. When determining osteoporosis on the original image, CNN showed sensitivity in a wide range of areas including not only the inferior cortical bone of the mandible but also the maxillary and mandibular cancellous bone, cervical spine, and zygomatic bone. When the same ROI including the lower inferior cortical border of the mandible of the osteoporosis group was applied and the sensitive region was compared between the original image and the limited image, the original image showed wider sensitive region in cancellous bone and cortical bone than on the limited image (p<.05). Since osteoporosis is a disease that affects throughout the skeletal system, this finding seems very valid.

The purpose of this study is to identify factors that influence consumers’ acceptance intentions towards Direct-to-Consumer (DTC) Genetic Testing service. DTC genetic testing service can be considered in two aspects: the application of new technology in genetic testing customers can directly purchase and the services for receiving the test results customer can’t directly analyze. Existing technology-based acceptance models have difficulty fully explaining consumers’ acceptance intentions towards DTC genetic testing services. Therefore, this study aims to propose a new acceptance model considering these two characteristics. A survey was conducted with 377 potential consumers for this research. The analysis revealed that health interest, prior knowledge, subjective norms, innovativeness, perceived usefulness, and perceived value affect consumers’ acceptance intentions. The results obtained through this study can help establish strategies and marketing plans necessary for the diffusion of services, such as DTC genetic testing services, that combine a new technology and a service. In the long term, the accumulated DTC genetic testing results data can contribute to the development of national genetic information infrastructure and preventive medical applications, as well as improve individuals’ quality of life.

목적: 가상현실을 구현하는 HMD의 광학계를 이용하여 가상현실 기반의 사위검사법을 개발하였다. 방법: HMD(Oculus rifts, Oculus, USA)를 이용하여 가상현실에 3m 및 40 cm의 사위 시표를 생성했을 때 HMD의 디스플레이에 송출된 타깃의 분리도를 측정하였고, 광학렌즈에 의해 결상된 디스플레이의 타깃 상 위치와 분리도, 배율 등을 산출하였다. 가상현실의 사위 시표는 수정된 토링톤 시표와 마독스 봉을 기반으로 제작했으며, 가상의 검사실을 제작하였고, 사위 측정 방법을 컨트롤러에 프로그래밍하였다. 결과: 가상현실에 3m 및 40 cm의 사위 시표를 생성했을 때 HMD의 디스플레이에 송출된 타깃의 분리도는 각 각 62.49mm, 58.29mm이었다. 디스플레이의 타깃은 광학렌즈에 의해 상 배율 8.07×로 광학렌즈로부터 전방 269.44mm에 상이 맺었으며, 타깃 상의 분리도는 각각 57.51mm, 20.16mm이었다. 사위 시표의 위치 인식은 HMD 사용자의 양안으로부터 양쪽 디스플레이의 타깃 상을 연결한 양안의 주시선이 교차하는 지점에서 이루어지는 것으로 나타났다. HMD를 착용했을 때 양쪽 디스플레이에 검사실 및 사위 시표가 생성되어 양안이 동시 주시를 하 였고, 컨트롤러의 트리거를 당겼을 때 우측 디스플레이의 영상이 적색선으로 교체되면서 양안의 시선이 분리되었 다. 사위검사 시 검사거리의 전환은 컨트롤러의 y-버튼을 이용했으며, 수평 사위 측정은 우측 컨트롤러의 트리거, 수직 사위 측정은 왼쪽 컨트롤러의 트리거를 이용하였다. 결론: 이상으로 가상현실을 기반의 사위검사법을 개발한 본 연구는 안경광학 분야에서 VR 기술의 활용에 대한 기초자료를 제시하였다고 생각한다.

이 연구는 통합기술수용이론(UTAUT)을 확장한 UTAUT2 모델을 활용 하여 치의학과 학생들의 UBT 수용의도에 영향을 미치는 요인을 분석하 고, 성별에 따른 조절효과를 검토하였다. 이를 위해 한 국립대학교 치의 학과 졸업시험에 응시한 학생 157명을 대상으로 설문조사를 실시하였다. 설문조사는 연구참여자의 성별, 나이, 입학 유형, 태블릿 PC 보유 여부, 스마트기기 활용 능력 등 인구통계학적 정보와 스마트기기 사용 경험, 그리고 UTAUT2 모델에 기반한 성과기대, 노력기대, 사회적 영향, 촉진 조건, 습관 등 요인과 UBT 수용의도를 평가하는 21개의 문항 등 총 27 개의 문항을 활용하였다. 설문조사 분석 결과에 따르면 사회적 영향과 습관 요인이 치의학과 학생들의 UBT 수용의도에 유의미한 영향을 미쳤 으며, 습관 요인과 UBT 수용의도간 관계에 대한 성별의 조절효과가 확 인되었다. 이러한 결과를 바탕으로 UBT 도입을 촉진하기 위해 학생들의 긍정적인 인식을 높이는 홍보 활동, 정기적인 연습 기회 제공, 성별 맞춤 형 접근, 기술적 지원과 자원 제공 등의 전략을 제안하였다.

Concrete structures must maintain their shielding abilities and structural integrity over extended operational periods. Despite the widespread use of dry storage systems for spent nuclear fuel, research on the properties of deteriorated concrete and their impact on structural performance remains limited. To address this significant research gap, static and dynamic material testing was conducted on concrete specimens carefully extracted from the outer wall of the High-flux Advanced Neutron Application ReactOr (HANARO), constructed approximately 30 years ago. Despite its age, the results reveal that the concrete maintains its structural integrity impressively well, with static compression tests indicating an average compressive strength exceeding the original design standards. Further dynamic property testing using advanced high-speed material test equipment supported these findings, showing the consistency of dynamic increase factors with those reported in previous studies. These results highlight the importance of monitoring and assessing concrete structures in nuclear facilities for long-term safety and reliability.

In this study, the SBC system, a new mechanical joint method, was developed to improve the constructability of precast concrete (PC) beam-column connections. The reliability of the finite element analysis model was verified through the comparison of experimental results and FEM analysis results. Recently, the intermediate moment frame, a seismic force resistance system, has served as a ramen structure that resists seismic force through beams and columns and has few load-bearing walls, so it is increasingly being applied to PC warehouses and PC factories with high loads and long spans. However, looking at the existing PC beam-column anchorage details, the wire, strand, and lower main bar are overlapped with the anchorage rebar at the end, so they do not satisfy the joint and anchorage requirements for reinforcing bars (KDS 41 17 00 9.3). Therefore, a mechanical joint method (SBC) was developed to meet the relevant standards and improve constructability. Tensile and bending experiments were conducted to examine structural performance, and a finite element analysis model was created. The load-displacement curve and failure pattern confirmed that both the experimental and analysis results were similar, and it was verified that a reliable finite element analysis model was built. In addition, bending tests showed that the larger the thickness of the bolt joint surface of the SBC, the better its structural performance. It was also determined that the system could improve energy dissipation ability and ductility through buckling and yielding occurring in the SBC.

Scabies, caused by an infestation of the skin with the itch mite (Sarcoptes scabiei), is highly contagious and classified as a prevalent neglected tropical diseases. The current diagnostic approach relies solely on clinical judgment based on symptoms, history, and microscopic observation by an experienced dermatologist. To enhance sensitivity and specificity, we developed an alternative method based on mite-derived DNA. Our method involves a quick DNA release from skin scraping samples and Loop-Mediated Isothermal Amplification (LAMP) targeting the scabies mite-specific DNA sequences, enabling diagnosis within 30 minutes. Importantly, no cross-reactivity was observed when the sample was contaminated by two house dust mite species, and false positives were barely detected. Currently, we are in the process of developing a Point-of-Care Testing (POCT) kit for a scabies survey targeting school-age children in Timor-Leste as a global health project.

기존 교량을 일체식 교대 교량과 같이 거동할 수 있도록 교대 흉벽과 상부슬래브를 일체화하는 흉 벽 일체식 교대 교량 공법에 관한 것으로, 교대 흉벽은 뒤채움 토사의 토압을 주요 하중으로 설계되기 때문에 배면부에는 휨보강 철근이 배치되지만 흉벽 일체화에 따른 흉벽 전면부에 온도팽창에 저항하 기에 부족한 철근량을 가지게 된다. 본 실험 연구는 일체화된 흉벽 구조체의 단차부 전면에 부착-정 착방식으로 제작된 FRP 보강체를 사용하여 휨 실험을 수행하고 이를 비교 분석하였다.

Background: The small intestine plays a crucial role in animals in maintaining homeostasis as well as a series of physiological events such as nutrient uptake and immune function to improve productivity. Research on intestinal organoids has recently garnered interest, aiming to study various functions of the intestinal epithelium as a potential alternative to an in vivo system. These technologies have created new possibilities and opportunities for substituting animals for testing with an in vitro model. Methods: Here, we report the establishment and characterisation of intestinal organoids derived from jejunum tissues of adult pigs. Intestinal crypts, including intestinal stem cells from the jejunum tissue of adult pigs (10 months old), were sequentially isolated and cultivated over several passages without losing their proliferation and differentiation using the scaffold-based and three-dimensional method, which indicated the recapitulating capacity. Results: Porcine jejunum-derived intestinal organoids showed the specific expression of several genes related to intestinal stem cells and the epithelium. Furthermore, they showed high permeability when exposed to FITC-dextran 4 kDa, representing a barrier function similar to that of in vivo tissues. Collectively, these results demonstrate the efficient cultivation and characteristics of porcine jejunum-derived intestinal organoids. Conclusions: In this study, using a 3D culture system, we successfully established porcine jejunum-derived intestinal organoids. They show potential for various applications, such as for nutrient absorption as an in vitro model of the intestinal epithelium fused with organ-on-a-chip technology to improve productivity in animal biotechnology in future studies.

The aim of this study is to evaluate the possibility of damage to cultural assets resulting from vibrations generated by construction vehicle traffic. The cultural heritage's natural vibration frequency was determined to be 150Hz by measurement. The damping ratios were calculated as 4.7% using the logarithmic decrement approach and 4.3% using the half-power method. The vibration measurements obtained during vehicle operation indicated that, despite an increase in vehicle velocity of up to 15 km/h, the vibrations remained below the detectable level of 0.13 mm/sec. When the road is curved and the terrain is sloped, a suitable speed for vehicle operation was found to be around 17 km/h, at which point vibrations were seen. The highest recorded vibration amplitude at this velocity was 0.217 mm/sec, which remains below the stringent regulation limit of 2 mm/sec. Thus, it can be concluded that there is no actual harm caused by vibrations.

Decommissioning waste is generated with various types and large quantities within a short period. Concrete, a significant building material for nuclear facilities, is one of the largest decommissioning wastes, which is mixed with aggregate, sand, and cement with water by the relevant mixing ratio. Recently, the proposed treatment method for volume reduction of radioactive concrete waste was proven up to scale-up testing using unit equipment, which involved sequentially thermomechanical and chemical treatment. According to studies, the aggregate as non-radioactive material is separated from cement components with contaminated radionuclides as less than clearance criteria, so the volume of radioactive concrete waste is decreased effectively. However, some supplementation points were presented to commercialize the process. Hence, the process requires efficiency as possible to minimize the interface parts, either by integration or rearranging the equipment. In this study, feasibility testing was performed using integrated heating and grinding equipment, to supplement the possible issue of generated powder and dust during the process. Previously, heat treatment and grinding devices were configured separately for pilot-scale testing. But some problems such as leakage and pipe blockage occurred during the transportation of generated fine powder, which caused difficulties in maintaining the equipment. For that reason, we studied to reduce the interface between the equipment by integrating and rearranging the equipment. To evaluate the thermal grinding performance, the fraction of coarse and concrete fines based on 1mm particle size was measured, and the amount of residual cement in each part was analyzed by wet analysis using 4M hydrochloric acid. The result was compared with previous studies and the thermomechanical equipment could be selected to enhance the process. Therefore, it is expected that the equipment for commercialization could be optimized and composed the process compactly by this study.

Concrete structures of spent nuclear fuel interim storage facility should maintain their ability to shield and structural integrity during normal, off-normal and accident conditions. The concrete structures may deteriorate if the interim storage facility operates for more than several decades. Even if deterioration occurs, the concrete structures must maintain their own functions such as radiation shielding protection and structural integrity. Therefore, it is necessary to establish an analysis methodology that can evaluate whether the deteriorated concrete structure maintains its integrity under not only normal or off-normal condition but also accident condition. In this study, dynamic material testing was conducted on concrete cores extracted from HANARO exterior wall during seismic reinforcement construction. HANARO was constructed at the Korea Atomic Energy Research Institute in 1995, following strict nuclear quality assurance standards. In order to conduct the dynamic material testing of the extracted concrete cores, self-disposal had to be performed because the concrete cores were extracted and stored in a radiation controlled area. A self-disposal application was prepared and submitted based on the radionuclide analysis results, and it was finally approved in April 2023. Then, a test was performed by processing a specimen for dynamic property testing using a self-disposed concrete core. The concrete cores were processed to create specimens for dynamic material testing and the dynamic material testing was performed to obtain stress-strain diagrams according to the strain rate.