• Journal of the Korean Institute of Electrical and Electronic Material Engineers
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• v.34 no.5
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• pp.283-295
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• 2021

For the last decades, a research hotspot for the halide perovskites (HPs) is now showing great progress in terms of improving efficiency for numerous photovoltaic devices (PVDs). However, it still faces challenges in the case of long-term stability in the air atmosphere. Defect-free high-quality HP single crystals show their promising properties for the remarkable development of highly efficient and stable PVDs. Here, we summarize the growth processing routes for the stable HP single crystals as well as briefly discuss the pros and cons of those well-established synthesis routes. Furthermore, we briefly include the comparison note between the HP single crystals and polycrystalline perovskite films regarding their device applications. Based on the future progress, the review concludes subjective perspectives and current challenges for the development of HPs high-quality PVDs.

• Journal of Powder Materials
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• v.29 no.1
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• pp.14-21
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• 2022

In the powder bed fusion (PBF) process, a 3D shape is formed by the continuous stacking of very fine powder layers using computer-aided design (CAD) modeling data, following which laser irradiation can be used to fuse the layers forming the desired product. In this method, the main process parameters for manufacturing the desired 3D products are laser power, laser speed, powder form, powder size, laminated thickness, and laser diameter. Stainless steel (STS) 316L exhibits excellent strength at high temperatures, and is also corrosion resistant. Due to this, it is widely used in various additive manufacturing processes, and in the production of corrosion-resistant components with complicated shapes. In this study, rectangular specimens have been manufactured using STS 316L powder via the PBF process. Further, the effect of heat treatment at 800 ℃ on the microstructure and hardness has been investigated.

• Journal of the Korean Institute of Electrical and Electronic Material Engineers
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• v.36 no.5
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• pp.513-519
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• 2023

It was reported that a tetragonal phase can be stabilized with maintaining good piezoelectric properties when Na_0.5K_0.5NbO₃ (KNN) is modified with 0.06 mol SrTiO₃. However, such a high amount of SrTiO₃ leads not only to poor sinterability but low Curie temperature (T_C). To maintain high TC with good piezoelectric properties in KNN-based lead-free piezoelectric ceramics, this study investigates the effect of Li-doping on the dielectric and piezoelectric properties of 0.96Na_0.5K_0.5NbO₃-0.04SrTiO₃ (KNN-4ST) ceramics. As a result, the orthorhombic-tetragonal phase transition was observed at 2 mol% Li₂CO₃ modified KNN-4ST ceramics, whose T_C, d₃₃ and k_p values are 328℃, 165pC/N and 0.33, respectively.

• Quality Improvement in Health Care
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• v.28 no.2
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• pp.14-29
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• 2022

Purpose:In order to improve the quality of cardiac rehabilitation, it is important to examine the experiences of the patients and how they feel about each part of the process. We used a qualitative research methodology to conduct an in-depth review of the experiences of patients who participated in cardiac rehabilitation. Methods: According to semi-structured guidelines, in-depth interviews were conducted with a total of five patients undergoing cardiac rehabilitation. Results: A total of 232 codes was derived; these codes were split into 4 categories and 10 subcategories. Although the patients were apprehensive about the diagnosis of heart disease, it also gave them a chance to reflect on their health behaviors of the past. In addition, they began to appreciate their families and support networks more as the disease progressed. The participants did not know about cardiac rehabilitation until the medical staff recommended it, but they participated in the program with the expectation that they could become healthier. The participants felt that they became more physically and mentally healthy while undergoing cardiac rehabilitation. Rehabilitation served as an opportunity to improve other health behaviors as well. However, they emphasized that it is necessary to continuously maintain improved health behavior, find an exercise method that is suitable for one's physical ability and not monotonous, and prepare a plan to reduce the time and economic burden of cardiac rehabilitation. Conclusion: The participants' positive experiences confirmed in this study will be used as evidence for the expansion of cardiac rehabilitation programs.

• Journal of Korean Medicine Rehabilitation
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• v.34 no.3
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• pp.13-26
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• 2024

Objectives This study aimed to examine the efficacy of Korean traditional medicine treatments for recurrent lumbar disc herniation by analyzing randomized controlled trials (RCTs). Methods The following 6 databases were used Korean studies Information Service System, Oriental Medicine Advanced Searching Integrated System, Research Information Sharing Service, ScienceON, PubMed, and China National Knowledge Infrastructure. Only RCTs were selected. The risk of bias was assessed by Cochrane's risk of bias tool. Results A total of 10 RCTs were analyzed, which utilized 8 types of interventions, including acupuncture, moxibustion, warm needling, electroacupuncture, herbal medicine, cupping, and chuna manual therapy. Acupuncture and moxibustion were the most frequently used treatments. There were 7 outcome measures, including the effective rate, visual analog scale, Japanese Orthopedic Association. The effective rate was assessed in all studies. Meta-analysis results indicated that warm needling therapy and traditional Chinese medicine interventions were more effective compared with the control. Conclusions In this study, warm needling therapy and herbal medicine interventions demonstrated beneficial effects. As the meta-analysis was conducted with only a subset of RCT studies, further large-scale, systematic RCT studies are needed.

• 건강소식
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• v.27 no.10 s.299
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• pp.42-43
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• 2003

• Proceedings of the Korean Environmental Sciences Society Conference
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• 1998.04a
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• pp.125-127
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• 1998

• Journal of the KSME
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• v.56 no.8
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• pp.52-56
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• 2016

이 글에서는 울산 산업단지의 에너지 네트워크의 추진 배경과 전략 그리고 사업화 현황을 살펴보고, 산업단지의 에너지 네트워크 확대를 위한 정책제언을 하고자 한다.

• 한국상하수도협회지
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• s.9
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• pp.16-21
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• 2005

• Bulletin of the Korean Chemical Society
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• v.19 no.4
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• pp.400-401
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• 1998