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Seaborne transportation by merchant vessels amounts to more than 90% of the world’s trade volume and it represents about 20% to 30% of the materials generated by the combustion of the total fuel. The International Maritime Organization (IMO) has enforced the use of 0.5% or less low-sulfur fuel oil when operation in all since 2020, and the installation of a scrubber is considered the most realistic alternative in compliance with IMO’s new regulation. However, the desulfurization process unavoidably creates a corrosive environment, and corrosion from it is mainly concentrated on welded materials. To solve the corrosion problem in that area, post-weld heat treatment was applied on Super Austenitic Stainless Steel (UNS N08031) which is commonly used for scrubbers. Upon heat treatment at 1,160 °C or at a higher temperature after welding, microsegregation of welds and base metals was dissolved. As a result, elements were distributed equally and the corrosion resistance increased due to the formation of a uniform oxide film.

This study scrutinizes the dam behavior during different rates of water level fluctuations via centrifuge model tests and verifies the results by numerical analyses. LVDTs and pore water pressure gauges were installed to scrutinize the settlement and pore water pressure behavior during different rates of water level fluctuation. The centrifuge model test results suggest that the increased rate of water level fluctuation increases the risk of dam failure as drastic variations in pore water pressure and differential settlement were observed. The differential settlement in the upstream and downstream sides of the dam due to water level fluctuation increases the risk of cracking in the dam crest. Also, the dam stability was evaluated by comparing and analyzing the pore pressure and deformation distribution values obtained from the centrifuge model tests with numerical analysis results. Soil-void fluid coupled analyses were performed in the steady and unsteady seepage flow conditions. The analysis results manifest that the increased rate of fluctuation in water level becomes a factor for a rapid increase in the displacement and pore pressure of the dam body, resulting in a reduction in the dam stability. Thus, real-time monitoring of the displacement and pore water pressure during rapid fluctuations in water level, such as heavy rain, is required to ensure dam stability.

This study analyzes the behaviors of the Kyeryong embankment dam during various rates, i.e., quick and slow rate, of water level fluctuation using geotechnical centrifuge experiments that simulate the real scale stress conditions and water level fluctuation conditions of the real field. The collapse behavior of the embankment is also evaluated, in this study, by simulating overflow conditions during torrential downpours due to climate change. The embankment models are constructed at a reduced scale of 1:50; the protected and unprotected embankment crest conditions are replicated, and pore pressure gauges, displacement sensors (linear variable differential transformer LVDT) are installed to analyze the seepage and overtopping behaviors of the embankment by carrying out geotechnical centrifuge tests. The centrifuge test results manifest that repetitive and continuous fluctuation of water level is a major factor that causes embankment deformation through the accumulation of pore water pressure and settlement. In addition, it is confirmed that the installation of protection measures along with spillway helps to prevent the scouring of soil particles in the embankment downstream slope .

Janghyeon dam, located at Gangneung-si with 6.9 m height and constructed in 1947, is modeled at a scale of 1:60 to analyze the seismic behaviors of the dam during seismic loading through dynamic centrifuge model tests. The centrifuge model tests are performed by simulating the field stress conditions and seismic loads. The results of dynamic centrifuge model tests show that the dam with an intact core satisfies the stability criteria against crest settlement. In contrast, a settlement of 1.2% of the dam height suggests that the dam with a deteriorated core does not satisfy the stability criteria. The acceleration amplification ratio from the core base to crest is 1.1–1.6 in the case of the intact dam and is 1.15–2.32 in the case of the deteriorated dam. Thus, it is inferred that the acceleration and settlement responses rely not only on seismic loads but also on the condition of the dam (i.e., intact or deteriorated). The acceleration amplification and settlement in the deteriorated dam are observed to be apparent. This is due to the weakening phenomenon of the dam by water that seeps through the deteriorated core, which increases pore water pressure and saturation level. Thus, the dynamic behaviors of the earth-filled dam, obtained through this study, can be used as primary data for seismic design and reinforcement of dam.

Purpose: The objective of this study was to investigate the effects of Kinesio taping (KT) for balance and gait in patients with stroke through meta-analysis of studies conducted in Korea. Methods: RISS, Science on, and DBPia were the three databases used to collect articles on KT. Keywords such as “Stroke,” “Kinesio tap ing,” “Elasticity taping,” and “Taping” were used to search for published articles. We systematically searched from the inception of each database to November 2020. Interventions and comparisons were KT and without KT. Outcome measures were the timed up and go (TUG) and 10-meter walking tests (10MWT). Consequently, six studies were selected for the second screening using meta-analyses. Results: Based on the results of the meta-analysis, comparison between patients with and without KT showed that KT was effective for TUG (ES: 2.51, 95% CI: 2.12 to 2.90); however, it was not effective for 10MWT (ES: 0.79, 95% CI: -0.04 to 1.62). Conclusion: The current evidence suggests that KT is more effective than without KT interventions for balance function in post-stroke patients. However, more well-conducted randomized controlled trials are required in the future.

많은 인테리어 관련 어플리케이션이 개발됨에 따라 일반인들도 인테리어 관련 전문영역에 쉽게 접근할 수 있게 되었다. 인테리어 관련 많은 기업들과 스타트업은 더욱 정확하고 전문적인 서비스 제공하기 위해 3D Scanning, 증강현실, 등 다양한 4차산업 기술과 접목해 연구와 개발을 진행하고 있다. 하지만 현재 일반 사용자에게 제공되는 서비스는 단순한 view 역할을 하거나 전문가가 아닌 일반인들이 사용하기 어려운 시스템이 많다. 이에 본 연구는 전문가가 아닌 일반 사용자들도 쉽게 접근하고 사용할 수 있는 3D Scanning과 다양한 기술을 접목한 모바일 인테리어 시스템을 제안하였다. 제안된 시스템을 기반으로 인테리어 전문가영역 수준의 정보를 제공받고, 견적서까지 받아 볼 수 있는 시스템 시나리오를 도출하였으며, 이는 사용자가 원하는 디자인 변경가능과, 디자인 변경을 위한 견적서 산출까지의 업무를 진행하여 효율적인 개인 맞춤형 인테리어 시스템이 될 것이라 예상된다.

Background: Although studies have been conducted on muscle thickness and balance in trunk stabilization exercise and exercise using vibration props, studies on trunk stabilization exercise using active vibration for spinal alignment are still insufficient to draw a conclusion.Objectives: To investigate the effect of trunk stabilization exercise using active vibration on the spinal alignment in adult females.Design: A randomized controlled trial.Methods: Twenty-six adult females were randomly assigned to the experimental group (active vibration) and 13 control groups (active non-vibrating) and exercised three times a week for 8 weeks. Each group was measured for spinal alignment before exercise and 8 weeks after exercise. Spinal alignment, trunk imbalance, pelvic tilt, and pelvic torsion were measured using a spinal alignment analyzer.Results: Trunk imbalance was a significantly different depending on the time in the experimental group and the control group (P .05). Pelvic torsion was no significant difference in both groups (P>.05).Conclusion: This study demonstrates that trunk stabilization exercise using active vibration has a positive effect on the alignment of the spine.

Due to less visibility, underground facilities such as sewer pipelines are subjected to degradation until a major failure occurs. So, leakage detection of deteriorated underground sewer pipes is necessary to prevent expensive rehabilitation costs. The major causes of the frequent occurrence of ground subsidence and sewer leakage are excessive use of groundwater, reckless exploitation of natural resources, etc. In this study, the aerial thermal imaging (ATI) technique has been used to identify the leakage points in sewer pipelines by analyzing surface thermal diffusion behavior of the ground surface. Leakage is suspected at points of anomalous temperature variation. Then, ground-penetrating radar and closed-circuit television surveys have been carried out to strengthen the suspicion of sewer leakage. Irregular, erratic parabolic-shaped lines are observed at the points where the leakage is suspected through ATI. Finally, the test-pit excavation and simple cone penetration tests have been carried out which confirms the sewer leakage points. The leakage points are confirmed by a greater depth of penetration. The results of the cone penetration test carried out in E-21 and 23-24 sewer pipelines show that the depth of penetration at the leakage points is about 35 cm, which is greater than the depth of penetration at other points. So, it can be concluded that the aerial thermal imaging technique is an effective method to predict leakage in deteriorated underground sewer pipelines.

Managed aquifer recharge (MAR), an intentional storage of excess water to an aquifer, is becoming a promising water resource management tool to cope with the worldwide water shortage. Bioclogging is a commonly encountered operational issue that lowers hydraulic conductivity and overall performance in MAR. The current study investigates the impact of carbon and nitrogen in recharge water on bioclogging in MAR. For this investigation, continuous-flow columns packed with sand grains were operated with influents having 0 (C1), 5 (C2), and 100 mg/L (C3) of glucose with or without introduction of nitrate. Hydraulic conductivity was analyzed to evaluate bioclogging in the systems. In C1 and C2, hydraulic conductivity was not significantly changed overall. However, hydraulic conductivity in C3 was decreased by 28.5% after three weeks of operation, which appears to be attributed to generation of fermentation bacteria. Introduction of nitrogen to C3 led to a further decrease in hydraulic conductivity by 25.7% compared to before it was added, most likely due to stimulation of denitrifying bacteria. These findings indicate that high carbon contents and introduction of additional nitrogen in recharge water cause serious bioclogging in MAR, suggesting the necessity for controlling quality of recharge water.

Background: Combination of metformin to reduce the fasting plasma glucose level and an α-glucosidase inhibitor to decrease the postprandial glucose level is expected to generate a complementary effect. We compared the efficacy and safety of a fixed-dose combination of voglibose plus metformin (vogmet) with metformin monotherapy in drug-naive newly-diagnosed type 2 diabetes mellitus. Methods: A total of 187 eligible patients aged 20 to 70 years, with a glycosylated hemoglobin (HbA1c) level of 7.0% to 11.0%, were randomized into either vogmet or metformin treatments for 24 weeks. A change in the HbA1c level from baseline was mea sured at week 24. Results: The reduction in the levels of HbA1c was -1.62%±0.07% in the vogmet group and -1.31%±0.07% in the metformin group (P=0.003), and significantly more vogmet-treated patients achieved the target HbA1c levels of