This study aims to assess the seismic performance of retrofitted reinforced concrete columns using a Replaceable Steel Brace (RSB) system, subjected to combined axial, lateral, and torsional loadings. Through experimental testing, one non-retrofitted concrete column specimen and two retrofitted specimens with variable sliding slot lengths were subjected to eccentric lateral loads to simulate realistic seismic loading. The retrofitted specimens with RSBs exhibited enhanced resistance against shear cracking, effective torsional resistance, and demonstrated the feasibility of easy replacement. The RSB system substantially improved seismic performance, achieving approximately 1.7 times higher load capacity and 3.5 times greater energy dissipation compared to non-retrofitted column, thus validating its efficacy under combined loading conditions.
Structural vibration induced by earthquake hazards is one of the most significant concerns in structure performance-based design. Structural hazards evoked from seismic events must be properly identified to make buildings resilient enough to withstand extreme earthquake loadings. To investigate the effects of combined earthquake-resistant systems, shear walls and five types of dampers are incorporated in nineteen structural models by altering their arrangements. All the building models were developed as per ACI 318-14 and ASCE 7-16. Seismic fragility curves were developed from the incremental dynamic analyses (IDA) performed by using seven sets of ground motions, and eventually, by following FEMA P695 provisions, the collapse margin ratio (CMR) was computed from the collapse curves. It is evident from the results that the seismic performance of the proposed combined shear wall-damper system is significantly better than the models equipped with shear walls only. The scrutinized dual seismic resisting system is expected to be applied practically to ensure a multi-level shield for tall structures in high seismic risk zones.
To ensure the safety and functionality of a railroad bridge, maintaining the integrity of the bridge via continuous structural health monitoring is important. However, most structural integrity monitoring methods proposed to date are based on modal responses which require the extracting process and have limited availability. In this paper, the applicability of the existing damage identification method based on free-vibration reponses to time-domain deflection shapes due to moving train load is investigated. Since the proposed method directly utilizes the time-domain responses of the structure due to the moving vehicles, the extracting process for modal responses can be avoided, and the applicability of structural health evaluation can be enhanced. The feasibility of the presented method is verified via a numerical example of a simple plate girder bridge.
Background: Previous robot-mediated gait training has been proven several limitations such as pointless repeated motion training, decreased presence, etc. In this research, adult stroke patients were participated in robot-mediated gait training accompanied with or without virtual reality program.
Objectives: Exploring whether the results indicated virtual reality system has contribution to muscle strength and balance ability.
Design: A case series research, cross-over trial.
Methods: Eleven participants (male 4, female 7) with adults diagnosed as stroke from medical doctor ware engaged. The participants received 2 treatment sessions of identical duration, robot-assisted gait training with virtual reality and robot-assisted gait training with screen-off randomly crossed over include 1-day for each person of wash-out period. The parameter was muscle activity, the researchers assessed sEMG (surface electromyography).
Results: The result showed less muscle activities during training in robotassisted gait training with virtual reality circumstances, and these indicated muscles were gluteus medius muscle, vastus medialis muscle, vastus intermedius and vastus lateralis muscle, semimembranosus muscle, gastrocnemius- lateral head, and soleus muscle (P<.05).
Conclusion: In this study, we analyzed the outcome of muscle activity for clinical inference of robot-assisted gait training with virtual reality (VR). Less muscle activity was measured in the treatment accompanied by VR, therefore, a more systematic, in-depth and well-founded level of follow-up research is needed.
This study is to improve the efficiency of BTL (Build Transfer Lease) project operation by comparing the infiltration rate based on the data of 5 years of infiltration of the separate sewer system and combined sewer system. In the survey site, the separate sewer system area consists of eight flowmeters in seven treatment basins, and the combined sewer system area consists of eight flowmeters in five treatment basins. The infillration rate was analyzed by night-time domestic flow evaluation method, and the average infiltration rates of the separate sewer system and combined sewer system were 13% and 16%, respectively. Combined sewer system was about 1.3 times higher than the separate sewer system. The average BOD of separate sewer system was 233 mg/L, which was about 2.4 times higher than the combined sewer system was 107 mg/L. In the comparison of the average pipe diameter-length infiltration of separate sewer system and combined sewer system, the separate sewer system and the combined sewer system were about 0.150 m3/d/mm/km and about 0.109 m3/d/mm/km, respectively. The floating population in mixed residential and commercial areas has been identified as the cause. Therefore, we propose a method to calculate the infiltration rate in consideration of the margin ratio in the area where the night active population is concentrated.
Aluminum alloys are the light weight materials, they are commonly used in many industrial applications such as electronic, aerospace, automotive, and medical industry. Because they are used in these such applications. Therefore, their light weight and high surface quality are required. In this paper, the surface improvement round flat aluminum alloy using lapping finishing method was explored. In order to find the optimal condition, lapping parameters such as, rotational speeds, abrasive grain sizes of pad, processing times, and lapping oils were investigated in this study. The improvement in surface roughness was found to be highest with optimal condition at 200 rpm of rotational speed, 1 ㎛ abrasive grain size of pad, 0.5ml of light oil for 720 sec. By using the optimal condition, the initial surface roughness Ra of round flat aluminum alloy can be enhanced from 2.59㎛ to 0.02 ㎛. This can be concluded that the small CNC machine with lapping finishing method can be used to enhance the surface roughness of round flat aluminum alloy effectively.
To ensure the safety and functionality of a railroad bridge, maintaining the integrity of the bridge via continuous structural health monitoring is important. However, most structural integrity monitoring methods proposed to date are based on modal responses which require the extracting process and have limited availability. In this paper, the applicability of the existing damage identification method based on free-vibration reponses to time-domain deflection shapes due to moving train load is investigated. Since the proposed method directly utilizes the time-domain responses of the structure due to the moving vehicles, the extracting process for modal responses can be avoided, and the applicability of structural health evaluation can be enhanced. The feasibility of the presented method is verified via a numerical example of a simple plate girder bridge.
본 연구에서는 조선소에서 작업자의 안전 확보를 위하여 스마트디바이스를 기반으로 동작, 체온, 외부온도, 맥박, 호흡, 청각적 기능을 탑재하였고, 이로부터 획득되는 정보들을 취합하여 서버 컴퓨터로 보내기 위한 클라이언트/서버 프로그램을 개발하였다. 또한, 작업자의 안전 상태를 진단할 수 있는 종합안전지수의 개념을 제시하였고 실제 선박에 탑승하여 센서모듈 및 스마트디바이스 테스트를 수행을 통해 획득된 데이터들에 대한 상관관계분석 및 다중 회귀분석을 통해 결과데이터와 센서 값 사이에 유의미한 상관관계를 가지고 있음을 확인하였다.
In accordance with the nature, characteristics, uses, etc. of the information that are as distinguishing criteria, information classification is a means clustering things meeting the same standard. Classification is the basis of scientific research. The purpose of Information Classification on handed down Chinese Dictionary in Japan, South Korea and China is to provide a professional platform for philology researchers easily retrieve and inquiry. And providing a theoretical basis for the development and application of the depth of shared dictionary database of East Asian. This article analyzes and studies Information Organization, Information Retrieval and Information Classification of handed down Chinese Dictionary in Japan, South Korea and China, the Paper noted that standardized information classification principles is a prerequisite for East Asian countries to regulate the construction of database of handed dictionaries ,and to maximize sharing Chinese character resources.
Pressure sores are painful and needless complications of critical illness. and manifest as a localized area of ischemic necrosis of tissue caused by pressure. This study analyzed the bed-backrest elevation system combined with hip and knee flexion for lower extremity lower pressure reduction. Eight healthy adults aged 21 to 26 years were recruited. The Body Pressure Measurement Mat of the TekScan system was used to measure the location and magnitude of the peak pressures on the body bed interface. The SPSS statistical package was used to analyze the significance of differences between the general bed-backrest elevation system and the bed-backrest elevation system combined with hip and knee flexion using the paired t-test. The result showed that the body-pressure of the lower extremity was more significantly reduced for the bed-backrest elevation system combined with hip and knee flexion (26.6±4.3 mmHg) than a general bed-backrest elevation system (37.3±5.2 mmHg) (p<.05).
본 연구에서는 광촉매 반응과 막분리 기술을 접목시킨 혼성 고도 정수처리 공정에서 소독 부산물의 전구체로 알려진 자연산 유기물을 효과적으로 제거하고자 하였고 다양한 운전 조건에서 시스템의 성능을 비교 평가하였다. 자연산 유기물은 흡입여과 방식의 분리막과 TiO2 광촉매를 이용하여 광분해하였을 때 광촉매 투입량의 증가에 따라 반응속도가 증가하였지만 과량의 촉매 주입시에는 반응 속도 향상에 오히려 부정적으로 작용하였다. 자연산 유기물을 보다 효과적으로 제거하기 위해 산화철 주입, TiO2 표면처리, 분리막 표면코팅을 시도하여 제거특성 및 운전에 따른 막여과 특성을 평가하였다. 산화철 주입은 초기에 흡착작용으로 인해 제거율 증가를 보였으나 반응이 진행됨에 따라 산화철 입자에 의한 광산란으로 광분해 효율이 오히려 감소되었다. 산화철 입자에 의한 광산란을 제어하고자 TiO2 표면을 광처리와 열처리 방법을 이용해 철을 직접 부착시킨 경우 긍정적인 효과를 얻지 못했다. 그러나 산화철로 막표면을 코팅하여 광산란 효과를 배제시킨 경우에는 향상된 결과를 보였다 막투과 플럭스 15 L/m2-h에서 정밀여과를 수행하였을 때 TiO2나 산화철에 의한 막오염은 거의 일어나지 않았고 안정된 막투과도를 나타내었다.
12주간의 복합운동프로그램이 노인의 스트레스와 자율 신경계 활성도에 미치는 영향을 규명하는데 있다. 방법: 연구대상자들은 65∼75세의 노인 14명으로 7명의 노인을 대상으로 복합 운동프로그램을 7명의 노인을 대 상으로 걷기 운동을 12주 동안 주 2회 실시하였다. 중재를 실시하기 전과 12주 후의 평가 결과를 분석하였다. 자 료 분석 방법은 SPSS 23.0 프로그램을 이용하여 t-검정, 반복측정 분산분석으로 분석하였다. 결과: 복합 운동프로 그램 그룹의 경우 12주 후 스트레스 저항도와 전체 자율신경 활성도에서 유의한 증가를 보였다. 비록 지각된 스 트레스와 신체수행능력 점수에서 대조군과 유이한 차이를 보이지 않았지만 복합 운동프로그램 그룹에서 중재 후 유의한 개선을 보여 긍정적인 양상을 볼 수 있었다. 결론: 이러한 연구결과를 통해 노인들의 자율 신경계 활성도 를 높여 심혈관계 질환을 예방하기 위한 운동 프로그램으로 복합 운동 프로그램을 제안한다.
Painting system are widely used to prevent corrosion damage The coating method on various corrosion preventive method was usually adopted for the functional ability and excellent appearance. In this study, to evaluate the deterioration curve of coating system for steel bridge, the combined cyclic corrosion test was conducted base on ISO 20340. The deterioration areas were measured depending on corrosion cycle. The deteriorations of newly-built coating were compared with those of re-coating.
본 연구에서는 열전소자와 플라즈마 장치를 삽입하여 제작된 컨테이너와 기존의 사용되고 있는 스티로폼(EPS)박스에 소고기를 저장하면서 저장 중 품질특성을 조사하였다. 온도변화 측정 결과 저장기간 동안 TCS-1 컨테이너가 2℃ 이하로 온도유지가 잘 되는 것으로 측정되었다. EPS박스는 저장 3일 이후 소고기가 부패되어 더 이상 실험이 불가능 하였다. 소고기의 신선도를 나타내는 휘발성염기질소(VBN)과 지방산패도(TBA)값의 측정 결과, 저장 7일째 TCS-1의 VBN은 7.72 mg%, TBA는 0.52 mgMA/kg, TCS-2의 VBN 값은 9.20 mg%, TBA는 0.91 mgMA/kg로 측정되어 TCS-1이 TCS-2 보다 유의적으로 적은 증가율을 나타내어 소고기의 신선도를 더 잘 유지하는 것으로 판단되었다. 미생물 변화는 저장 7일 TCS-1은 4.62 log CFU/g, TCS-2는 7.09 log CFU/g으로 측정되어 TCS-1이 유의적으로 미생물 증식 억제에 효과적인 것으로 나타났다. 기호도 조사 또한 저장 7일째 TEU-1은 모든 항목에서 6.5점 이상의 평가를 받았으나 TCS-2는 4.1 이하의 평가를 받아 소고기의 상품성이 상실된 것으로 판단되었다. 모든 분석항목에서 TCS-1이 TCS-2보다 소고기 신선도 유지에 효과적인 것으로 판단되었다.
For the distribution of fresh produce, the thermoelectric cooling system combined with thermo electric materials (TEM) and phase change material (PCM) was studied. The PCM used this study was produced by in-situ polymerization technology which referred microencapsulation of hydrocarbon (n-tetradecane and n-hexadecane). In this study, quality characteristics of bell peppers in thermoelectric cooling system combined with TEM and PCM were analyzed and control was placed in an EPS (expanded polystyrene) box. As a result of quality characteristics analysis, weight of bell peppers decreased and moisture content of bell peppers was 90.96~94.43% during storage. Vitamin C content of bell pepper decreased during storage and reduction ratio of control was higher than that of BPT-5 treatment(bell pepper in thermoelectric cooling system with PCM which is kept the temperature at 5℃). The result of color value, on 21 day, ΔE value of BPT-5 treatment was 5.05 while that of control was 41.8. On 21 day, total bacteria count of BPT-5 treated bell pepper shown less than that of control. In conclusion, it suggested that the thermoelectric cooling system combined with PCM improved quality of fresh produce during transportation and storage.