• Korean Journal of Construction Engineering and Management
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• v.23 no.3
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• pp.116-127
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• 2022

Recently, the smart city market based on the 4th industrial revolution is rapidly expanding worldwide and is being promoted in various ways. Korea has promoted various smart city public and private partnership projects, but there were limits to the activation of smart city public and private partnership projects due to insufficient enactment and revision of laws, public-oriented ordering method, and lack of private execution capacity. Therefore, this study intends to suggest key success factors for each stage of smart city public and private partnership projects through the analysis of the order status of the smart city national pilot city and the analysis of previous research. Through this, it is expected that it will be possible to eliminate various types of risks that may occur in the domestic smart city public and private partnership projects and contribute to revitalizing the smart city public and private partnership projects.

• Membrane Journal
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• v.32 no.6
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• pp.442-455
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• 2022

High-temperature polymer electrolyte membrane fuel cell (HT-PEMFC) has been studied as an alternative to low-temperature PEMFC due to its fast activation of electrodes and high resistance to electrode poisoning by carbon monoxide. It is highly required to develop stable PEMs operating at high temperatures even doped by ion-conducting materials for the development of high-performance and durable HT-PEMFC systems. A number of studies have been conducted to develop polybenzimidazole (PBI)-based PEMs for applications in HT-PEMFC due to their high interaction with doped ion-conducting materials and outstanding thermomechanical stability under high-temperature operation. This review focused on the development of PBI-based PEMs showing high performance and durability. Firstly, the characteristic behavior of PBI-based PEMs doped with various ion-conducting materials including phosphoric acid was systematically investigated. And then, a comparison of the physicochemical properties of the PEMs according to the different membrane manufacturing processes was conducted. Secondly, the incorporation of porous polytetrafluoroethylene substrate and/or inorganic composites to PBI matrix to improve the membrane performances was studied. Finally, the construction of cross-linked structures into PBI-based PEM systems by polymer blending method was introduced to improve the PEM properties.

• The Journal of Korean Academy of Orthopedic Manual Physical Therapy
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• v.29 no.1
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• pp.1-9
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• 2023

BACKGROUND: The purpose of this study was to find out which exercise is more effective for the activation of the trunk, when the suspension plank and modified bridge exercise are performed. Weakening of the trunk muscles can lead to secondary injuries such as back injuries. In order to prevent injury, trunk muscles must be strengthened, and representative trunk strengthening exercises include planks and bridges. Each has been developed with a modified method, but since there is no paper comparing which exercise is more effective for trunk muscle strength, it was written to compare the two exercises. METHODS: The subjects were a random sample of 30 healthy men who agreed to participate in the study. The subjects were divided into two groups of 15 people each, and the suspension plank and the modified bridge exercise were performed for six weeks. The thickness of the transverse abdominis (TrA), internal abdominal oblique (IO), external abdominal oblique (EO), rectus abdominis (RA), multifidus (MF) was measured before and after the exercise. The two groups were analyzed using an independent t-test and paired t-test to compare the muscle thickness and the difference before and after exercise. RESULTS: The trunk muscle thickness was increased in both groups with suspension plank and modified bridge exercise, and there was a statistically significant difference. When comparing the two groups, the suspension plank group also showed a significant difference in RA (p<.05). CONCLUSION: As a result of this study, suspension plank exercise can have a positive effect on activating the trunk muscles and strengthening the strength of RA. Therefore, it is considered that suspension plank exercise is a more effective intervention to strengthen trunk muscle than modified bridge exercise.

• Asia-pacific Journal of Multimedia Services Convergent with Art, Humanities, and Sociology
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• v.7 no.4
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• pp.403-413
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• 2017

The study was conducted to understand the meaning of the voluntary service experience of Korean-Chinese who living in South Korea and examine the reason of participating in voluntary activities. 8 people participated in the study, who come from volunteering groups in a Korean-Chinese compact community. Data were collected through in - depth interviews and participation observation. The collected data were categorized and analyzed according to Giorgi's hermeneutic phenomenological research method. As a result of the analysis, three sets of themes were drawn on the nature of their volunteering experience. Through their volunteer activities, they have been improving their images that have been damaged and stigmatized by the mainstream society. Through their volunteer activities, they have improved their self-esteem, got more information about the society and better adapted to Korean society. Moreover, through their volunteer activities, they have increased their sense of responsibility for Korean society and redefined their position in Korea. Given this, they expect the possibility of becoming a global citizen for the future. The meanings of volunteer experience of Chinese Koreans have been examined and discussed in this study, which indicated that the activation of the volunteer activities of migrants contributes positively to the integration of multicultural society.

• Korea Science and Art Forum
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• v.19
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• pp.243-257
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• 2015

The Cultural Heritage Administration has selected Seoul Fortress Wall as the representative heritage of Korea to be applied for being registered as UNESCO World Heritage and announced the plan to restore and organize it, which has increased the interest to the Seoul Fortress Wall, the Historical Site No. 10. The great work to make the heritage value of Walls, 4 Big Gates and 4 Small Gates composing the Seoul Fortress wall with the length of 18.627 km to be recognized worldwide has limits if it is focused only on the physical restoration. It is because the Seoul Fortress Wall represents the long historical and cultural value as the space of life which connects closely the capital city and its vicinity. We need the plan to discover and utilize historical and cultural contents of Seoul Fortress Wall and its vicinity. Especially, Gwangheemun, which is one of the four Small Gates of Seoul Fortress Wall, is a precious cultural heritage which represents the transition of fortification technology of Chosun period as the space representing ordinary people. However, now Gwangheemun and its vicinity does not stand out the charm because of passive accessibility, landscape falling behind and absence of program. This made the lack of domestic and overseas tourists and the convenient space and various contents. This reality is because the value of space has been considered simply as a cultural heritage without considering the traditional, historical and cultural specificity. Therefore, this study is aimed to find the meaning and value of Gwangheemun by discovering its own latent intangible cultural, historical and artistic resource, and to find the way to connect with Gwangheemun, the existing tangible traditional architectural space and the way of vitalizing Gwangheemun as a new space.

• Korean Chemical Engineering Research
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• v.61 no.3
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• pp.472-478
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• 2023

In this study, the acetaldehyde removal characteristics of activated carbon (AC) for air purifier filters were investigated using metal catalysts-impregnation and functional group-modification method. The AC with a high specific surface area(1700 m²/g) and micropores was prepared by KOH activation of coconut charcoal and the efficiency of catalyst and functional group immobilization was examined by varying the drying conditions within the pores after immersion. The physical properties of the prepared activated carbon were analyzed by BET, ICP, EA, and FT-IR, and the acetaldehyde adsorption performances were investigated using gas chromatography (GC) at various impregnation and modified conditions. As the concentration of impregnation solution increased, the amount of impregnated metal catalysts increased, while the specific surface area showed a decreasing trend. The adsorption tests of the metal catalyst-impregnated and functional group-modified activated carbons revealed that excellent adsorption performance in compositions MgO10@AC, CaO10@AC, EU10@AC, and H-U3N1@AC, respectively. The MgO10@AC, which showed the highest adsorption performance, had a breakthrough time of 533.8 minutes and adsorption capacity of 57.4 mg/g for acetaldehyde adsorption. It was found that the nano-sized MgO catalyst on the activated carbon improved the adsorption performance by interacting with carbonyl groups of acetaldehyde.

• Journal of Korean Medicine Rehabilitation
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• v.33 no.4
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• pp.15-29
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• 2023

Objectives The purpose of this study is to systematically review the effects of Neuromuscular Electrical Stimulation treatment on muscle wasting in cancer patients. Methods Randomized controlled trials (RCTs) were searched from seven online databases (PubMed, Cochrane Library, EMBASE, China National Knowledge Infrastructure, Oriental Medicine Advanced Searching Integrated System, Korean studies Information Service System, Research Information Sharing Service. The selected RCTs were evaluated for methodological quality through the Cochrane RoB. Results A total of 126 articles were identified, and 4 randomized controlled trials were selected for systematic review. In one study, it was found that there were statistically significant improvements in the Health-Related Quality of Life (FACTH&N total score, p<0.001). Additionally, significant effects were observed in measurements that represented the size of the quadriceps muscle (cross-sectional area of Vastus lateralis and Rectus femoris, p=0.004), maximum muscle strength, the twitch response of resistance muscles, and voluntary activation (p<0.001). However, no significant differences were observed between the intervention and control groups in terms of quadriceps muscle strength in two other studies (p>0.05). Lastly, while one study showed no significant differences in muscle fiber characteristics between the two groups, it did report significant improvements in measurements related to mitochondria within muscle tissue and muscle strength in the intervention group (p<0.05). Conclusions Neuromuscular electrical stimulation can be a method used to improve muscle strength in muscle wasting of cancer patients, but it is difficult to see its effects as significant compared to other treatments.

• KIPS Transactions on Software and Data Engineering
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• v.12 no.12
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• pp.519-524
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• 2023

In hashing-based image retrieval, the hash code of a manipulated image is different from the original image, making it difficult to search for the same image. This paper proposes and evaluates a self-supervised deephashing model that generates perceptual hash codes from feature information such as texture, shape, and color of images. The comparison models are autoencoder-based variational inference models, but the encoder is designed with a fully connected layer, convolutional neural network, and transformer modules. The proposed model is a variational inference model that includes a SimAM module of extracting geometric patterns and positional relationships within images. The SimAM module can learn latent vectors highlighting objects or local regions through an energy function using the activation values of neurons and surrounding neurons. The proposed method is a representation learning model that can generate low-dimensional latent vectors from high-dimensional input images, and the latent vectors are binarized into distinguishable hash code. From the experimental results on public datasets such as CIFAR-10, ImageNet, and NUS-WIDE, the proposed model is superior to the comparative model and analyzed to have equivalent performance to the supervised learning-based deephashing model. The proposed model can be used in application systems that require low-dimensional representation of images, such as image search or copyright image determination.

• Journal of the Korea institute for structural maintenance and inspection
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• v.28 no.2
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• pp.27-34
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• 2024

This study was conducted to examine the feasibility of using Fe-activated wood-derived biochar as a conductive filler for manufacturing cement-based strain sensor. To evaluate the compressive and electrical properties of cement composite with 3% Fe-activated biochar, three cubic specimens of size 50 x 50 x 50mm³ and three prismatic cement-based sensors of size 40 x 40 x 80mm³ were prepared respectively. The four-probe method of electrical resistance measurement was used for cement-based sensors. For cement-based sensors with FE-activated biochar, the conductive performance such as electrical resistance and impedance under different water content and repeated compression was investigated. Results showed that the fractional changes in the DC electrical resistivity of cement-based sensors increase with increasing time and the maximum fractional changes in the resistivity decrease with increasing the moisture contents during 900s. At moisture content of 7.5% range, the conductive performance of cement composite including 3% Fe-activated biochar as a conductive filler showed the most stable, while the strain detection ability tended to decrease somewhat as the repeated compressive stress increased between repeated compressive strain and fractional change in resistivity (FCR).

• Korean Chemical Engineering Research
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• v.62 no.2
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• pp.147-152
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• 2024

Most medical sensors are disposable products. In order to reduce inspection and diagnosis costs, it is more important to develop the inexpensive electrode materials. We fabricated the CuO NPs/PANI/E-PGE as an electrode material for disposable electrochemical sensors and applied it to a non-enzymatic glucose sensor. For surface activation of PGE, pretreatment was performed using chemical and electrochemical methods, respectively. Electrochemical properties according to the pretreatment method were analyzed through chronoamperometry (CA), cyclic voltammetry (CV) and electrochemical impedance (EIS). From these analytical results, the electrochemically pretreated PGE (E-PGE) was finally adopted. The non-enzymatic glucose sensor based on CuO NPs/PANI/E-PGE shows sensitivity of 239.18 mA/mM×cm² (in a linear range of 0.282~2.112 mM) and 36.99 mA/mM×cm² (3.75423~50 mM), detection limit of 17.6 μM and good selectivity. Based on the results of this study, it was confirmed that the modified PGE is a high-performance electrode material. Therefore, these electrodes can be applied to a variety of disposable sensors.