• International Journal of Computer Science & Network Security
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• v.23 no.3
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• pp.110-122
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• 2023

Over the last few decades, various innovative technologies have emerged that have significantly contributed to making life easier for humans. Various information and communication technologies (ITCs) have emerged as a result of the global technological revolution, including big data, IoT, 4G and 5G networks, cloud computing, mobile computing, and artificial intelligence. These technologies have been adopted in urban planning and development, which gave rise to the concept of smart cities in the 1990s. A smart city is a type of city that uses ITCs to exchange and share information to enhance the quality of services for its citizens. With the global population increasing at unprecedented levels, cities are overwhelmed with a myriad of challenges, such as the energy crisis, environmental pollution, sanitation and sewage challenges, and water quality issues, and therefore, have become a convergence point of economic, social, and environmental risks. The concept of a smart city is a multidisciplinary, unified approach that has been adopted by governments and municipalities worldwide to overcome these challenges. Though challenging, this transformation is essential for cities with differing technological and social features, which all have the potential to determine the success or failure of the digital transformation of cities into smart cities. In recent years, researchers, businesses, and the government have all turned their attention to the emerging field of smart cities. Accordingly, this paper aims to represent a thorough understanding of the movement toward smart cities. The key themes identified are smart city definitions and concepts, smart city dimensions, and smart city architecture of different layers. Furthermore, this article discusses the challenges and some examples of smart cities.

• Asia-pacific Journal of Multimedia Services Convergent with Art, Humanities, and Sociology
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• v.8 no.2
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• pp.657-666
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• 2018

This study was carried out to investigate what kind of problems gender equality in Chinese married immigrant women have in marriage. We interviewed five Chinese marriage immigrant women married to Korean men for research. Using the case study method, which is a qualitative research method, five research participants analyzed gender equality awareness and gender equality conflict after migration. As a result, the marital conflicts, which are the difference of recognition of gender equality among married immigrant women, were different according to the family life culture of their home countries, the route of meeting with their husbands, and their understanding of Chinese culture. Nonetheless, most of the research participants showed that they accepted the Korean women's values in the form of conforming to the Korean patriarchal system while taking the inequality by attempting to assimilate positively in Korean society. And some of them resulted in the failure of the family because of the patriarchal values of the Korean husband. Based on the results of this study, we discussed the problems of gender equality in multicultural families in Korea and discussed ways to improve them.

• KSCE Journal of Civil and Environmental Engineering Research
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• v.26 no.5C
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• pp.313-322
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• 2006

Liquefaction of soil foundation is one of the major seismic damage types for infrastructures. In this paper, deterministic and probabilistic approaches for the evaluation of liquefaction potential are briefly summarized and the risk assessment method is newly proposed using seismic fragility and seismic hazard analyses. Currently the deterministic approach is widely used to evaluate the liquefaction potential in Korea. However, it is very difficult to handle a certain degree of uncertainties in the soil properties such as elastic modulus and resistant capacity by deterministic approach, and the probabilistic approaches are known as more promising. Two types of probabilistic approaches are introduced including (1) the reliability analysis (to obtain probability of failure) for a given design earthquake and (2) the seismic risk analysis of liquefaction for a specific soil for a given service life. The results from different methods show a similar trend, and the liquefaction potential can be more quantitatively evaluated using the new risk analysis method.

• KSCE Journal of Civil and Environmental Engineering Research
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• v.28 no.6D
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• pp.819-829
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• 2008

Fatigue cracking occurs over long time period because dynamic strength of slab continuously decreases by vehicle loading repetitively applied to the concrete pavement. To more accurately predict the fatigue life of the concrete pavement, the stress due to environmental loading should be considered prior to calculating the stress due to the vehicle loading because the stress due to temperature and moisture distribution always exists within the slab. Accordingly, a new fatigue model considering the environmental loading was developed in this research by evaluating factors of existing fatigue models most widely used and by making data points from the models. The applicability of the new model was evaluated by performing a fatigue analysis on the general concrete pavement structure using local climatic and traffic conditions in Korea. It was concluded that the top-down cracking due to the tensile stress at top of the slab is dominant cause of the fatigue failure than the bottom-up cracking occurred at bottom of the slab. More advanced fatigue analysis considering vehicle speed is expected by developing this study.

• Korean Journal of Exercise Nutrition
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• v.16 no.1
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• pp.27-33
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• 2012

This study was conducted to investigate the effect of a 24-week combined exercise training program in older women with hypertension. Women with hypertension who were 70 years and older were randomized into two groups: combined exercise group (CE; n = 15) and a control group (n = 15). The CE group performed a combined exercise training program four times per week for 24 weeks and the control group did not. Five factors, including body composition (percent body fat and skeletal muscle mass), health-related physical fitness, adipocytokines (interleukin-6 [IL-6] and tumor necrosis factor-alpha [TNF-α]), kidney risk factors (glomerular filtration rate [GFR] and cystatin C), and systolic and diastolic blood pressure were measured before and after the program. The findings showed that total muscle mass, health-related physical fitness factors, and GFR increased significantly in the CE group compared to those in the control. Additionally, systolic and diastolic blood pressure and IL-6, TNF-α, and cystatin C levels in the CE group decreased significantly after the intervention. In contrast, total muscle mass decreased significantly and blood pressure remained unchanged in the control group. These results suggest that CE training may positively impact circulating levels of adipocytokines and cystatin C and improve physical fitness levels in elderly women with hypertension. Therefore, CE training helps to prevent renal disease and improve health-related physical fitness, eventually leading to a better quality of life.

• Structural Engineering and Mechanics
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• v.84 no.2
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• pp.155-165
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• 2022

The use of electricity and communication between electronic devices is increasing daily, which makes the stability of electrical power supply vital. Since the 1990s, large earthquakes have occurred frequently causing considerable direct damage to electrical power facilities as well as secondary damage, such as difficulty in restoring functions due to the interruption of electric power supply. Therefore, it is very important to establish measures to protect electrical power facilities, such as transformers and switchboards, from earthquakes. In this study, a 154 kV transformer whose service life had expired was installed on the base fabricated by simulating the field conditions and conducting the shaking table tests. The dynamic characteristics and seismic behavior of the 154 kV transformer were analyzed through the resonance frequency search test and seismic simulation test that considers the front, rear, left, and right directions. Since the purpose of this study is to analyze the acceleration amplification in the bushing due to the acceleration amplification, the experimental results were analyzed focusing on the acceleration response and the converted acceleration amplification ratio rather than the failure due to the displacement response of the transformer. The seismic force amplification at the transformer bushing was evaluated by simulating the characteristics of electrical power facilities in South Korea, and compared with the IEC TS 61463 acceleration amplification factor. Finally, the amplification factor at zero period acceleration (ZPA) modified for each return period was summarized. The results of this study can be used as data to define the amplification factor at ZPA of the transformer bushing, simulating the characteristics of electrical power facilities in Korea.

• Restorative Dentistry and Endodontics
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• v.47 no.2
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• pp.16.1-16.9
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• 2022

Objectives: This study compared the cyclic fatigue resistance of One Curve (C wire) and F6 Skytaper (conventional austenite nickel-titanium [NiTi]), and 2 instruments with thermos-mechanically treated NiTi: Protaper Next X2 (M wire) and Hyflex CM (CM wire). Materials and Methods: Ten new instruments of each group (size: 0.25 mm, 6% taper in the 3 mm tip region) were tested using a rotary bending machine with a 60° curvature angle and a 5 mm curvature radius, at room temperature. The number of cycles until fracture was recorded. The length of the fractured instruments was measured. The fracture surface of each fragment was examined with a scanning electron microscope (SEM). The data were analyzed using one-way analysis of variance and the post hoc Tukey test. The significance level was set at 0.05. Results: At 60°, One Curve, F6 Skytaper and Hyflex CM had significantly longer fatigue lives than Protaper Next X2 (p < 0.05). No statistically significant differences were found in the cyclic fatigue lives of One Curve, F6 Skytaper, and Hyflex CM (p > 0.05). SEM images of the fracture surfaces of the different instruments showed typical features of fatigue failure. Conclusions: Within the conditions of this study, at 60° and with a 5 mm curvature radius, the cyclic fatigue life of One Curve was not significantly different from those of F6 Skytaper and Hyflex CM. The cyclic fatigue lives of these 3 instruments were statistically significantly longer than that of Protaper Next.

• Korean Journal of Culture and Social Issue
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• v.12 no.2
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• pp.77-100
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• 2006

This study investigates happy life experiences and their emotional responses to these experiences with a sample of Korean students and adults. A total of 489 Korean university students and adults completed an open-ended questionnaire developed by the present researchers. Three sets of results have been found. First, while experiences of achievement and failure affect the strength of feelings of happiness or unhappiness, social relationships with family members and friends affect the frequency of feelings of happiness or unhappiness. Second, while strong positive affects are aroused by sense of achievement and pride, frequent positive affects are aroused by feeling of calmness and positive relational emotions (such as Jung - deep affection and attachment). Third, while strong negative affects are aroused by sense of frustration and sadness, frequent negative affects are aroused by anxiety and negative relational emotions (such as the sense of indebtedness and shame). These results indicate that the interpersonal relationships with family members and friends and personal achievements and failures influence the subjective well-being of feeling happy or unhappy with people's lives.

• Journal of The Korean Association For Science Education
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• v.29 no.8
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• pp.861-873
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• 2009

This study investigated the types of analogies generated by science-gifted students, mapping errors on the chromatography, and the perceptions on generating analogy. The subjects were science-gifted eighth-graders (N=68) enrolled at four gifted-education centers in Seoul. Analyses of the results revealed that most science-gifted students represented the analogies using verbal and pictorial forms based on concrete and everyday experiences, and they elaborately explained them including the functional attributes and the causal relationships of the target concept. Science-gifted students selected the analogies having rich similarities or similar structure and principle between the target concept and the analogy as the best of the self-generated analogies. And they used mainly their 'school life' as analogy materials. The results of the mapping test showed that many science-gifted students had mapping errors such as 'failure to map' and 'overmapping'. They were found to have the positive perceptions on generating analogy. The present study will provide the basic information to develop an instructional model in generating analogy in an education program for science-gifted students.

• Archives of Plastic Surgery
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• v.51 no.2
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• pp.258-261
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• 2024

Career building can be challenging for young surgeons, especially when topics such as lifestyle, work-life balance and subspecialization arise. Suggestions and advice from senior colleagues is very valuable but many young surgeons do not have such opportunities or are limited to a few senior surgeons. The International Microsurgery Club (IMC), in collaboration with the World Society of Reconstructive Microsurgery, organized a combined webinar for this topic and invited world renownedmicrosurgery masters polled by the IMCmembers to join, including Prof. Peter Neligan (Emeritus from University of Washington, United States), Prof. Raja Sabapathy (Ganga Hospital, India), Dr. Gregory Buncke (The Buncke Clinic, United States), Prof. Isao Koshima (Hiroshima University Hospital, Japan), Prof. David Chwei-Chin Chuang (Chang Gung Memorial Hospital, Taiwan), and Prof. Eric Santamaria (Hospital General Dr. Manuel Gea Gonzalez, Mexico) on May 1, 2022. Prof. Joon-Pio Hong (Asan Medical Center, South Korea) and Prof. Fu-Chan Wei (Chang Gung Memorial Hospital, Taiwan) were also selected but unfortunately could not make it and were therefore invited to another event in April 2023, summarized in a recently published paper. There is ample literature reporting on different aspects of developing a microsurgical career but the goal of this session was to offer an opportunity for direct exchange with experienced mentors. Moreover, insights from experienced microsurgeons from different part of the world were more likely to offer different perspectives on aspects such as career building, failure management, and team culture. This webinar event was moderated by Dr. Jung-Ju Huang (Taiwan), Dr. Susana Heredero (Spain), and Dr. Wei F. Chen (United States).