This study was investigated the effect of heat treatment on the microstructure and hardness of internally hardened ductile cast iron roll. The following conclusions were obtained. Some of the graphite was decreased and a bainite was produced by heat treatment. It decreased due to the decomposition of some of the cementite precipitated in the as-cast by heat treatment, but there was no significant change when it reached a certain depth. Hardness increased due to formation of bainite by heat treatment. On the surface, the hardness decreased due to the decrease in the amount of transformation of cementite into bainite, but there was no change beyond a certain depth.

In this study, the mechanical properties of friction stir welded A6061-T6 were evaluated. This material is used as a battery pack case material for electric vehicles. The Vickers hardness, tensile strength, and yield stress of the friction stir welding (FSW) specimen were all smaller than those of the base metal specimen. As the heat input increased, the nugget zone widened, and there were differences in hardness according to the base metal zone, heat affected zone, thermal-mechanical affected zone, and nugget zone. Mechanical properties were not proportional to heat input, and the thermal-mechanical affected zone on the advancing side was the smallest in all conditions. This is because the material flow speed increased on the advancing side, where the welding direction and the tool rotation direction were the same, forming a distinct boundary with mechanical deformation.

Recently, retail technology has been developed by the rapid evolution of e-commerce and a representative example is ESL technology. In this study, we investigate ESL technology, market status and forecasts, and analyze the competitive structure between relational companies. Market analysis refers to data from market reports of Marketsandmarkets and Research, and internet media. In ESL, the display field is predicted to account for 43% of the total market in 2026, and is converting from LCD to electronic paper. The segmented type is becoming more advanced into the full-graphic type, and CAGR of 18.7% for 3-7 inches and 20.6% for 7-10 inches is predicted. The demand for ESL is greatest in North America and Europe, but CAGR is the highest in the Asia-Pacific region at 19.1%. Since ESL technology has a lot of overlap with semiconductor and display technology, the Asia-Pacific region is relatively advantageous, and this has led to rapid growth of domestic companies. However, it is expected that competition from European companies that are actually owned by Chinese companies will increase in the future, so continuous technological development and new market development are necessary.

The objective of this study was to create intelligent rail robots that are optimized for facility management and implement digital twin systems for smart road tunnel management. An autonomous surveillance system is formed by combining the sensing platform consisting of railing robots, fixed cameras and environmental detection sensors with the digital twin data platform technology for tunnel monitoring and early fire suppression. In order to develop mobile rail robots for fire extinguishing, we also designed and manufactured robots for extinguishing & monitoring and fire extinguishing devices, and then we examined the optimization of all parts. Our next step was to build a digital twin for road tunnel management by developing continuous image display system and implementing 3D modeling. After constructing prototypes, we attempted simulations by configuring abnormal symptom scenarios, such as vehicles fires. This study's proposal proposes high-accuracy risk prediction services that will enable intelligent management of risks in the tunnel with early response at each stage, using the data collected from the intelligent rail robots and digital twin systems.

As the development of hydrogen vehicles has accelerated in recent years, it is necessary to develop a storage tank for hydrogen fueling stations capable of high-pressure charging, and for this purpose, a new system with a compressor-embedded refueling tank is required. In this study, the parametric study of shape design based on strength performance evaluation was carried out to find the optimal shape design of bellows, the core component of compressor-embedded refueling tank for a newly developed hydrogen refueling station capable of high-pressure charging above 1,000 bar. The design factors for parametric study were contour shape and radius of bellows, and the performance factors were the maximum stress and the gap distance in the contact direction. In the shape design of the compressor bellows for hydrogen refueling station considered in this study, it was found that adjusting the contour radius is an appropriate design method to improve the compression performance and structural safety.

The purpose of this study is to provide basic data on effective urban regeneration projects and development directions for improving the quality of life of local residents by analyzing urban regeneration projects that have been carried out so far according to evaluation items on public design characteristics. The research method was divided into literature review and case study. The research results are as follows. First, through analysis of previous research, seven evaluation items for public design characteristics were derived: publicness, accessibility, regional identity, aesthetics, communication, functionality, and sustainability. The research subjects were four urban regeneration project cases carried out across the country. Second, among the seven evaluation items for public design characteristics, publicness was all highly applied, but the other six items were applied differently in each case. Third, to increase sustainability, we must use eco-friendly materials and consider sustainable maintenance methods, functionality must be strengthened in terms of functionality and comfort of public facilities and public spaces, and communicability must be improved for local tourists. We actively look for ways to communicate with the public, accessibility involves incorporating more universal design, aesthetics focuses on adding beauty to spaces and facilities, and regional identity focuses on the unique and unique characteristics of each region. We suggest finding a theme and actively using it in urban regeneration projects. Lastly, for an urban regeneration project to be successful, it is necessary to effectively apply not only publicness but also accessibility, local identity, aesthetics, communication, functionality, and sustainability. In the future, public design characteristics should be more actively applied and considered in urban regeneration projects.

This study conducted a measurement method of high temeprature conditions using infrared termography. All objects emit infrared light, and this emissivity has a significant impact on the temperature measurements of infrared thermal imaging (IR) cameras. In order to measure the temperature more accurately with the IR camera, correction equations were derived by measuring the emissivity according to the temperature change of combustible metals in a high-temperature environment. Two combustible metals, Mg and Al, were used to measure emissivity with changing temperature. Each metal was heated, the emissivity was measured by comparing the temperature with IR camera and thermocouples so that the correlation between temperature and emissivity could be anslyzed. As a result of the experiment, the emissivity of the metals increases as the temperature increased. This can be interpreted as a result of increased radiation emission as the thermal movement of internal metal molecules increased.

Lithium-ion batteries (LIB) are widely used in various sectors, such as transportation (e.g., electric vehicles (EV)) and energy (e.g., energy storage facilities) due to their high energy density, broad operating temperature (-20 ℃ ~ 60 ℃), and high capacities. LIBs are powerful but fragile on external factors, including pressure, physical damage, overheating, and overcharging, that cause thermal runaway causing fires and explosions. During a LIB fire, a large amount of oxygen is generated from the decomposition of ionogenic materials. A water fire extinguisher that helps with cooling and suffocating must be essentially required at the same time. In fact, however, it is difficult to suppress LIB fires in the case of EVs because a LIB is installed with a battery pack housing that interrupts direct extinguishing by water. Thus, this study aims to investigate effective fire extinguishing measurements for LIB fires by using an EV. Relevant documents, including research articles and reports, were reviewed to identify effective ways of LIBs fire extinguishing. A real-scale fire experiment generating thermal runaway was carried out to figure out the combustion characteristics of EVs. This study revealed that the most effective fire extinguishing measurements for LIB fires are applying fire blankets and water tanks. However, there is still a lack of adequate regulation and guidelines for LIB fire extinguishment. Taking this into account, developing functional fire extinguishment measurements and available regulatory instruments is an urgent issue to secure the safety of firefighters and citizens.

Automatic production systems are constantly advancing technologies to improve productivity and safety. Specifically, liquid filling machines are primarily utilized to package products into drums after manufacturing process in the hazardous chemical industry. Most existing filling machines allow the operator to open the drum cap and inject the product directly or semi-automation. In this study, we have developed a cap opening and closing mechanism onto the existing drum filling machine, enabling automatic and safe cap manipulation while filling the product in the IBC tank. By applying the appropriate torque value through numerical analysis, we confirmed that the system worked without any problems during the process of opening and closing the cap. Therefore, it is expected that the developed machine will give more production and reduce human efforts without risk in the chemical packaging industry.

Urban Air Mobility (UAM) is considered the future of transportation, offering solutions to urban challenges and reducing environmental issues through the use of electric power and leveraging the sky as a new transportation corridor. UAM has diverse applications, including passenger and goods transportation, emergency rescue operations, patient transfers, and urban tourism. Furthermore, it is poised to revolutionize the transportation landscape, impacting existing infrastructures such as roads and parking lots, along with autonomous vehicles. The UAM industry is anticipated to exert a significant impact on various sectors, including airframe manufacturing, the development of new materials (e.g., fuel cells and batteries), and even the defense industry, resulting in substantial economic benefits. Consequently, conducting proactive research and setting industry standards for UAM takeoff and landing infrastructure is crucial for securing market leadership. In this regard, the case of Pontoise-Cormeiles, France, stands out as it achieved the world's inaugural successful demonstration of a vertiport before the 2024 Olympics. This achievement has significant implications for our preparations for the commercialization of UAMs. Thus, a detailed review of the French vertiport construction case in this study will serve as a foundation for guiding the planning and operation of UAMs in South Korea, particularly in anticipation of upcoming demonstration tests.

This study is on modulo scheduling algorithms for multicore processor in machine learning applications. Machine learning algorithms are designed to perform a large amount of operations such as vectors and matrices in order to quickly process large amounts of data stream. To support such large amounts of computations, processor architectures to support applications such as artificial intelligence, neural networks, and machine learning are designed in the form of parallel processing such as multicore. To effectively utilize these multi-core hardware resources, various compiler techniques are being used and studied. In this study, among these compiler techniques, we analyzed the modular scheduler, which is especially important in one core's computation pipeline. This paper looked at and compared the iterative modular scheduler and the swing modular scheduler, which are the most widely used and studied. As a result, both schedulers provided similar performance results, and when measuring register pressure as an indicator, it was confirmed that the swing modulo scheduler provided slightly better performance. In this study, a technique that divides recurrence edge is proposed to improve the minimum initiation interval of the modulo schedulers.

시료의 조단백질은 CJ4가 가장 높고 조지방, 수분, 회분, pH와 물리적인 특성은 주박분말이 많을수록 높았고 보수력은 낮았다. TBA의 CJ1은 지방산패 진행이 빨라 15일부터 가식할 수 없는 결과였다. 미생물 성장은 CJ1이 빠르게 증식하였고 CJ2, CJ3, CJ4는 15일 이후에도 부패취가 없어 주박분말이 저장성에 유용한 것으로 판단된다. 주박분말이 많을수록 L은 낮은 명도 a는 높은 적색 b는 높은 황색을 보였다. 관능검사 CJ1은 Color, Overall CJ2는 Flavor, Taste가 높은 선호도를 보였다. 주박을 첨가한 소시지의 외부 기호도는 CJ1를 내부 표현인 Overall은 CJ2를 활용한 저장성 연장관련 제품개발이 가능할 것으로 사료된다.

The purpose of this study is to examine the dual mediating effects of peer alienation and aggression in the relation between child abuse and delinquency in adolescents. Data were collected from 352 junior high school students living in Jeonbuk from October 2021 to December 2021. This study used a structured self-administered questionnaire to collect the data. In order to analyze the data, SPSS 26.0 and SPSS Process macro 4.0 program were used. The results showed that child abuse had statistically significant positive effect on delinquency via peer alienation. Also, child abuse had statistically significant positive effect on delinquency via aggression. In addition, child abuse had statistically significant positive effect on delinquency via peer alienation and aggression. Therefore, the dual mediating effects of peer alienation and aggression were verified. Based on the study results, implications for preventing adolescents' delinquency and suggestions for future study were discussed.

Purpose: The purpose of this study was to investigate the relationship between nursing students' metacognition, professional self-concept, and self-leadership and to identify the factors affecting nursing students' self-leadership. Methods: Data were collected from 195 nursing students in the first, second, and third years of nursing college located in J province, and a survey was conducted from November 13, 2023 to November 24, 2023. The collected data were analyzed through descriptive statistics, t-test, one-way ANOVA, Scheffe test, Pearson's correlation coefficient, and stepwise multiple regression analysis using SPSS/WIN 29.0 program. Result: Metacognition of the subjects showed a significant positive correlation with professional self-concept (r=.68 p<.001) and self-leadership (r=.79, p<.001), and professional self-concept showed a significant positive correlation with self-leadership(r=.67, p<.001). The major factors influencing self-leadership of nursing students were metacognition, professional self-concept, self-satisfaction, and perceived leadership level in order, and their explanatory power was 67%(F=79.92, p<.001). Conclusion: Based on the results of this study, it is necessary to develop an education program that improves metacognition and professional self-concept in order to strengthen the self-leadership of nursing students, and efforts should be made to introduce and manage it in the nursing curriculum.

This study aimed to investigate the effects of a twilight childcare programs for grandparents. The study used a non-equivalent control group and pretest-posttest design. It was conducted from September 1 to November 30, 2023 at senior centers in apartment complex in K city. It analyzed 45 (22 in the experimental group and 23 in the control group.) For data analysis, descriptive statistics, test of homogeneity in pretest, independent t-tests, and repeated measures ANOVA were used. In parenting confidence, the interaction between group and time showed a significant difference (F=30.54, p<.001). In Parenting Stress, the interaction between group and time showed a significant difference(F=10.68, p<.001), For Family Relationships, there was no significant difference in the interaction between group and time. A significant difference was found for life satisfaction(F=3.37, p=.047). This program is effective in increasing parenting confidence and life satisfaction, and reducing parenting stress.

The production and procurement of shipbuilding and offshore equipment is an important competitive factor in the shipbuilding and offshore industry. Recently, ICT-based digital technology has been rapidly applied to the manufacturing industry following the Fourth Industrial Revolution. Under the digital transformation, real-time data interface technology based on SCM (Supply Chain Management) is emerging as an important tool to improve the efficiency of the equipment manufacturing process. In this study, the characteristics and advantages and disadvantages of interface technologies of web-based data interface technologies were compared and analyzed. The performance was compared between theoretical evaluation based on technical features and practical application cases. As a result, it was confirmed that GraphQL is useful for selective data processing, but there is a problem with optimization, and REST API has a problem with receiving data due to a fixed data structure. Therefore, this study aims to suggest ways to utilize and optimize these data interface technologies.

Artificial Neural Networks that enabled Artificial Intelligence are being used in many fields. However, the application to mechanical structures has several problems and research is incomplete. One of the problems is that it is difficult to secure a large amount of data necessary for learning Artificial Neural Networks. In particular, it is important to detect and recognize external forces and forces for safety working and accident prevention of mechanical structures. This study examined the possibility by applying the Current Neural Network of Artificial Neural Networks to detect and recognize the load on the machine. Tens of thousands of data are required for general learning of Recurrent Neural Networks, and to secure large amounts of data, this paper derives load data from ANSYS structural analysis results and applies a stacked auto-encoder technique to secure the amount of data that can be learned. The usefulness of Stacked Auto-Encoder data was examined by comparing Stacked Auto-Encoder data and ANSYS data. In addition, in order to improve the accuracy of detection and recognition of load data with a Recurrent Neural Network, the optimal conditions are proposed by investigating the effects of related functions.

Approximately 89% of all capsizing accidents involve small vessels, and despite their relatively high accident rates, small vessels are not subject to ship stability regulations. Small vessels, where the provision of essential basic design documents for stability calculations is omitted, face challenges in directly calculating their stability. In this study, considering that the majority of domestic coastal small vessels are of the Chine-type design, the goal is to establish the major hull form characteristic data of vessels, which can be identified from design documents such as the general arrangement drawing, as input data. Through the application of a deep learning approach, specifically a multilayer neural network structure, we aim to infer hydrostatic curves, operational draft ranges, and more. The ultimate goal is to confirm the possibility of directly calculating the initial stability of small vessels.

While the current share of marine energy in South Korea is less than 1%, it is globally recognized as a resource approximately four times the annual electricity production. Considering the diverse geographical features of the East Sea, South Sea, and West Sea, marine energy development is crucial for South Korea and essential for achieving the 2050 carbon neutrality goal. Policy efforts for marine energy deployment focus on establishing an innovative, open, and integrated R&D system to respond flexibly. The construction of a scientific, economic, and social valid site selection system, along with a maritime spatial planning regime that considers environmental and socio-economic impacts, is emphasized. To expedite the early activation of marine energy, comprehensive policy endeavors, including discriminatory support policies and participation in international standardization, are anticipated to contribute to the sustainable development and dissemination of marine energy. Marine renewable energy plays a significant role in sustainability and addressing climate change, considered an essential component of South Korea's efforts toward carbon neutrality.

Recurrent Neural Network technology that learns past patterns and predicts future patterns using technology for recognizing and classifying objects is being applied to various industries, economies, and languages. And research for practical use is making a lot of progress. However, research on the application of Recurrent Neural Networks for evaluating and predicting the safety of mechanical structures is insufficient. Accurate detection of external load applied to the outside is required to evaluate the safety of mechanical structures. Learning of Recurrent Neural Networks for this requires a large amount of load data. This study applied the Gated Recurrent Unit technique to examine the possibility of load learning and investigated the possibility of applying a stacked Auto Encoder as a way to secure load data. In addition, the usefulness of learning mechanical loads was analyzed with the Gated Recurrent Unit technique, and the basic setting of related functions and parameters was proposed to secure accuracy in the recognition and prediction of loads.

This study is descriptive research study to understand the impact of digital ethics-literacy, multicultural acceptance, and global citizenship of medical students' on cultural competency. The subjects for this study were the medical students of J city of Province of G, collecting data from first of October to 15th of October 2023. The tools used for this study consist of 178 questions which were 9 questions of general properties, 70 questions of digital ethics-literacy, 35 questions of multicultural acceptance, 3qustions of global citizenship and 33 questions of cultural competency. As a result of this study, the score of digital ethics-literacy was 2.67±0.85(out of 5), the score of multicultural acceptance was 3.62±1.08(out of 6), the score of global citizenship was 3.72±0.75(out of 5), and the score of cultural competency was 3.49±0.71(out of 5). There is a positive correlation between multicultural acceptance and global citizenship. The global citizenship was the factor affecting significantly on cultural competency. The power of explication was 20.8%. The education for accepting and understanding cultural diversity and offering opportunity of domestic and overseas volunteering programs so that global citizenship could be improved. There is also a need of development of integrative education programs in terms of multicultural education including direct and indirect digital media education which can perform medical service for various multicultural recipient on the medical site not an one-shot instiiled displine.

Recently, with the strengthening of environmental regulations, there has been an increasing interest in eco-friendly energy sources, leading to a trend of the increasing scale of Cargo Containment Systems (CCS) for Liquefied Natural Gas (LNG) carriers. Among these systems, membrane tanks have gained popularity in LNG transport vessels due to their superior spatial utilization and competitiveness. However, due to high initial investment costs and the difficulty in repair in case of damage, a safety layer, the secondary barrier, must be installed without fail. In this study, in order to apply a new secondary barrier to the existing membrane-type LNG CCS, tests were conducted on the fiberglass layer previously used in the Triplex-Flexible Secondary Barrier (FSB), substituting it with basalt fiber. Tensile and vertical tensile tests were performed to assess the newly applied material. Environmental tests were conducted at room temperature (25℃) and extremely low temperatures (-170℃), considering the temperatures to which substances may be exposed during LNG vessel operations. The basalt-FSB produced in this study demonstrated superior results compared to the specifications of the existing product, confirming its potential applicability for implementation.

Purpose: The purpose of this study was to investigate the relationship between emotional intelligence, nursing professionalism, and resilience of nursing students and to identify the factors affecting resilience of nursing students. Methods: Data were collected from 205 nursing students in the 1st, 2nd, and 3rd grades of nursing colleges located in J province, and a survey was conducted from November 20th to November 30th, 2023. The collected data were analyzed through descriptive statistics, t-test, one-way ANOVA, Scheffe test, Pearson's correlation coefficient, and stepwise multiple regression analysis using SPSS/WIN 29.0 program. Result: The emotional intelligence of the subjects showed a significant positive correlation with nursing professionalism(r=.56 p<.001) and resilience(r=.75, p<.001), and nursing professionalism showed a significant positive correlation with resilience(r=.55, p<.001). The major factors influencing the resilience of nursing students were emotional intelligence, nursing professionalism, academic performance, and personality in order, and their explanatory power was 62% (F=83.05 p<.001). Conclusion: Based on the results of this study, it is necessary to develop an educational program that improves emotional intelligence and nursing professionalism in order to strengthen the resilience of nursing students.

The logistics industry is converging with digital technology and growing into various logistics automation systems. However, inspection and loading/unloading, which are mainly performed in logistics work, depend on human resources, and the workforce is shrinking due to the decline in the productive population due to the low birth rate and aging. Although much research is being conducted on the development of automated logistics systems to solve these problems, there is a lack of research and development on load stacking stability, which has the potential to cause significant accidents. In this study, loading boxes with various sizes and positions of the center of gravity were set up, and a method for stacking that with high stability is presented. The size of the loading box is measured using a depth camera. The loading box's weight and center of gravity are measured and estimated by a developed device with four loadcells. The measurement error is measured through various repeated experiments and is corrected using the least squares method. The robot arm performs load stacking by determining the target position so that the centers of gravity of the loading boxes with unbalanced masses with a random sequence are transported in alignment. All processes were automated, and the results were verified by experimentally confirming load stacking stability.

In this study, we examined changes in the food consumption patterns of Korean adults due to COVID-19 using the results of the 2019 and 2021 adult household member food consumption behavior surveys. In the weight and BMI analysis results, both men and women showed a significant increase in 2021 compared to 2019 (male; p<0.01 female; p<0.001). The frequency of breakfast skipping was found to increase with none and over 5 times. As for interest in domestic agricultural products, the proportion of 'not interested' and 'average' responses decreased, while the proportion of those who responded 'interested' increased (p<0.01). The rate of eating out was found to have significantly decreased in 2021 compared to 2019. As a result of the eating lifestyle analysis, the taste seeking type, quality safety seeking type, and health seeking type also showed an increase in 2021 compared to 2019, and a significant level was confirmed. In the purchasing competency index, the use of labeling for agricultural products, use of agricultural food information, and agricultural food purchasing environment items all showed significantly improved results in 2021 compared to 2019, and the eating competency index showed a significant increase in healthy eating and traditional eating habits. Through this study, we aim to suggest directions for establishing food marketing strategies and dietary education for adults in the event of a future pandemic.