• Economic and Environmental Geology
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• v.54 no.6
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• pp.743-752
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• 2021

The three-dimensional distribution of the fault was evaluated using gravity field interpretation such as curvature analysis and Euler deconvolution in the Seoul-Gyeonggi region where the Chugaryeong fault zone was developed. In addition, earthquakes that occurred after 2000 and the location of faults were compared. In Bouguer anomaly of Chugaryeong faults, the Pocheon Fault is an approximately 100 km fault that is extended from the northern part of Gyeonggi Province to the west coast through the central part of Seoul. Considering the frequency of epicenters is high, there is a possibility of an active fault. The Wangsukcheon Fault is divided into the northeast and southwest parts of Seoul, but it shows that the fault is connected underground in the bouguer anomaly. The magnitude 3.0 earthquake that occurred in Siheung city in 2010 occurred in an anticipated fault (aF) that developed in the north-south direction. In the western region of the Dongducheon Fault (≒5,500 m), the density boundary of the rock mass is deeper than that in the eastern region (≒4,000 m), suggesting that the tectonic movements of the western and eastern regions of the Dongducheon Fault is different. The maximum depth of the fracture zone developed in the Dongducheon Fault is about 6,500 m, and it is the deepest in the research area. It is estimated that the fracture zone extends to a depth of about 6,000 m for the Pocheon Fault, about 5,000 m for the Wangsukcheon Fault, and about 6,000 m for the Gyeonggang Fault.

• Journal of Korean Society of Occupational and Environmental Hygiene
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• v.32 no.3
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• pp.242-252
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• 2022

Objectives: Firefighters and police officers are exposed to various occupational hazards. No studies in Korea have investigated the occurrence of cancer by type of cancer for the two occupations. This study aims to investigate the risk of occurrences associated with types of cancers in firefighters and police officers. Methods: Utilizing National Health Insurance(NHI) Claims data from 2006-2015, the study included 8,871,468 general workers, 25,001 firefighters, and 102,274 police officers. Using general workers as a control group, we calculated the standardized incidence ratios(SIR) by types of cancer for firefighters and police officers. After calculating the SIR for all subjects, the SIR was calculated by stratifying according to gender. Results: SIR of colon cancer 1.38(95% CI, 1.11-1.69), cancer of the liver and intrahepatic bile ducts 1.27(95% CI, 1.04-1.54), and 1.88(95% CI, 1.28-2.65) bladder cancer were higher firefighters than general workers. SIR of Lip, oral cavity, and pharynx 1.26(95% CI, 1.07-1.47), Stomach 1.14(95% CI, 1.06-1.23), colon 1.33(95% CI, 1.21-1.46), liver and intrahepatic bile ducts 1.21(95% CI, 1.10-1.32), pancreas 1.24(95% CI, 1.02-1.49), other skin 1.60(95% CI, 1.26-2.00), bladder 1.27(95% CI, 1.04-1.54), other urinary tract 1.46(95% CI, 1.27-1.68), other parts of central nervous system 1.68(95% CI, 1.10-2.46) were higher police officers than general workers. Conclusions: Both firefighters and police officers are exposed to various cancer occurrence risks, necessitating the development of occupational medical protection measures to reduce risk exposure factors.

• Journal of the Korea Institute of Building Construction
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• v.21 no.3
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• pp.231-239
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• 2021

Entering the era of the fourth industrial revolution, information and communication technologies such as CCTV, home network systems and equipment are being used in the construction industry. In particular, in order to increase the autonomy of information and communication technologies in apartments, the government has announced an administrative revision of information and communication-related laws, and companies are focusing on developing technologies such as smart home services. In addition, most domestic and foreign studies on the information and communication work were mainly conducted on technology and management. However there is a lack of research on physical defects affecting the quality of ICT. Therefore, this study collected the defect data registered in the project management system of three domestic construction companies and classified them according to the standards of the Enforcement Decree of the Apartment House Management Act. According to the analysis of the frequency of defects work type, 88.10% of defects occurred in home network equipment work. In addition, analysis of defects type in the four detailed works showed the highest number of operation error. The cause was analyzed and prevention measures and countermeasures were presented in parts of design, construction, and maintenance. The results of this study will improve the quality of apartment housing and be used as basic data for future research on practical defect minimization and prevention measures.

• Journal of Practical Engineering Education
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• v.14 no.1
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• pp.119-125
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• 2022

Materials used for education are materials such as SM20C, Al6061, and acrylic. SM20C materials are carbon steel and are often used in certification tests and functional competitions, but are also widely used in industrial sites. The Al6061 material is said to be a material that has lower hardness and stronger flexibility than carbon steel, so it is a material that generates a lot of compositional selection of tools. If students are taught practical training using acrylic materials, vibration occurs due to excessive cutting in some parts and damage to the tool occurs. In this process, we examine to what extent the impact on the 2NC head, which is a five-axis equipment, can affect precision control. The weakest part of the five-axis equipment can be said to be the weakest part of the head that controls the AC axis. When the accuracy and cumulative tolerance of this part occur, the accuracy of all products decreases. Therefore, the core part of the 2NC head, the spindle housing, was carried out using an Al7075 T6 (Alcoa, USA) material. In the process of vibration and cutting applied to this material, the analysis was conducted to find out the value applied to the finite element analysis under extreme conditions. It is hoped that this analysis data will help students see and understand the structure of 5-axis machining rather than 5-axis cutting.

• Journal of Service Research and Studies
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• v.13 no.1
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• pp.144-158
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• 2023

R&D (Research and Development) investment by companies and the government continues to increase, and the total R&D expenditure of public and private sectors in 2021 reached KRW 102 trillion, and the ratio of R&D investment to GDP was 4.96%. It ranks second in the world after Israel. This study analyzes the current status of the domestic R&D service industry and the research and development (R&D) innovation ecosystem based on the business activity survey data of the National Statistical Office in terms of improving R&D productivity of domestic R&D investment that has exceeded 100 trillion won, and analyzes the global R&D service industry and analyzes the global research service industry and R&D service Industry support government policy As a result of the analysis, in the domestic R&D ecosystem, the R&D outsourcing demand of service companies is rapidly increasing, compared to the stagnant R&D outsourcing demand of traditional manufacturing companies. In order to respond to these changing demands for technological innovation, this study suggests balanced support for R&D outsourcing for manufacturing and service companies, expansion of domestic R&D outsourcing, establishment of R&D outsourcing strategies specialized for the service industry, establishment of an open R&D ecosystem, and innovation in connection with materials/parts/equipment strategies.

• Industry Promotion Research
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• v.8 no.2
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• pp.157-164
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• 2023

Since there are no related laws and regulations in the Korean private investigation industry, anyone can freely operate it if they report the business to the tax office. The reality is that companies hire PI to investigate rival companies and employees for specific reasons, as they generally rely on individual requests. The Korean PI industry is divided into two parts. The first are retired police officers and investigators who have experience in criminal investigation. The second are private citizen who can conduct investigation service activities runs a PI agency after everyone has registered with the tax office. It is no exaggeration to say that the current legal conflicts and legal problems that arise in the PI service cannot be ruled out because civilians are relatively less knowledgeable than PIs and legal experts. Therefore, in order for PI industry to operate stably in Korea, we will first study the concept and type of PI industry, comparative analysis of past PI laws, current status and reality of PI industry, and study the current status and references.

• Advanced Industrial SCIence
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• v.2 no.2
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• pp.9-15
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• 2023

Since silicone rubber heaters are flexible, they can be directly attached or installed in objects to be heated even in flat, curved or three-dimensional shapes. Since the current heating method heats the entire object to be heated and raises it to a required temperature, ignoring areas or positions where heat is not required, partial intensive heating cannot be performed. When using multi-heating zones, rather than heating the entire object to be heated, only the parts that need heat are intensively heated according to the process, so it is possible to heat quickly by local location by applying different amounts of heat with a small amount of electric capacity to each place that needs heat, and heat energy can reduce. In this study, the temperature and heating time of the partially concentrated region in the multi-heating region structure are measured so that a uniform temperature or temperature difference occurs in the region requiring thermal fusion. In order to determine the optimal power density range and reduce capacitance, the safety of a silicon rubber heater manufactured with a multi-heating zone structure is investigated. If the silicon rubber heater is manufactured in a multi-heating method, the multi-intensive heating technology can be ideally applied to all heating processes.

• The Korean Journal of Franchise Management
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• v.2 no.1
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• pp.134-151
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• 2011

The strategy for brand alliance is a new type of franchise to iron out the problems like the hotel restaurant's structural contradiction and decreasing profits caused by keen competition with external restaurants. This study is purposed to present the decisive factors for the brand alliance throughexamining the correlations between the brand restaurant designation standards and the expected effects from local low- and mid-priced hotel's brand alliance. The questionnaires were distributed to instructors and professors who have experience in teaching the food and beverage sections at college's hotel and tourism departments and 100 specialists at managerial level of a hotel's food and beverage parts.This survey was conducted for 20 days from December 2 to 22, 2004 and analyzed by independent t-test and canonical correlation analysis. The findings of this survey are as follows.Firstly, the service of the expected effect factors of the brand alliance was recognized relatively high by the specialists in hotel industry, while the sales effect factor of restaurant designation standards was recognized higher by the academic experts.The specialists of the hotel industry recognized the factors of menu and corporate culture higher than the academic experts. Secondly, the entire factors of the brand restaurant designation standards showed a correlation with the whole factors of the restaurant designation standards.In particular, the 'menu' factor presented the most influential to the expected effects of brand alliance.The factors of 'risk reduction' and 'synergy effect' exerted the strongest effect on the restaurant designation standards, which indicated the mutual correlation between the expected effect of brand alliance and the restaurant designation standards. Based on this study, the correlation between the expected effect of brand alliance and brand restaurant designation standards may play a primary role to choose a partner for the brand alliance, a decisive factor for the success.The execution of the brand alliance or the method to designate the alliance partner may vary from the hotel's desirable effects when the brand alliance is determined.In other words, the partner designation standards should be corresponding to the expected effects from the brand alliance between hotel and brand restaurant, and the academic and industrial experts' perceived differences in the expected effects of brand alliance and restaurant designation standards should be clarified to display the direction of decision-making and find the potential risks.

• KSCE Journal of Civil and Environmental Engineering Research
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• v.28 no.3A
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• pp.341-347
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• 2008

Among coating systems used for steel bridge coatings on highway such as red lead-pigmented alkyd, chlorinated rubber, waterborne inorganic zinc, inorganic zinc/epoxy/urethane and inorganic zinc/epoxy/fluororesin, evaluation of deterioration degree and prediction of lifetime through regression analysis were carried out for coating systems widely used and grossly degraded. For evaluation of deterioration degree, 75 bridges on highway were selected, and evaluations were carried out according to point offering method regulated by Guideline of maintenance coating for steel bridges used in Korea Expressway Corporation. Lifetime prediction results showed 13.0~13.3 years for the whole nation, 11.8 years for urban and industrial region in the metropolitan area, 13.2 years for rural region except the metropolitan area, 13.5~13.7 years for chlorinated rubber coating systems, and 12.86 years for red lead-pigmented alkyd systems. For prediction of the rest life of coating, we tried to execute parallel translations of standard deterioration curve to current life and deterioration degree for both x and y axes, and it was thought that parallel translation for x axis corresponded to deterioration aspects in actual environment. Maximum and minimum equations were derived from standard deterioration equation by adding and subtracting error values deduced in regression analysis to/from each coefficient in order to establish maintenance coating criteria for overall steel bridges on highway. Whole domain was divided into 8 parts in order to predict the rest life of coating and optimum time of maintenance coating, and maintenance coating criteria for each 8 domains were presented.

• Journal of the Microelectronics and Packaging Society
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• v.31 no.1
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• pp.29-34
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• 2024

The heating element utilizing the Joule heating generated when current flows through a conductor is widely researched and developed for various industrial applications such as moisture removal in automotive windshield, high-speed train windows, and solar panels. Recently, research utilizing heating elements with various nanostructures has been actively conducted to develop flexible heating elements capable of maintaining stable heating even under mechanical deformation conditions. In this study, flexible polyurethane possessing excellent flexibility was selected as the substrate, and silver (Ag) thin films with low electrical resistivity (1.6 μΩ-cm) were fabricated as the heating layer using magnetron sputtering. The 2D heating structure of the Ag thin films demonstrated excellent heating reproducibility, reaching 95% of the target temperature within 20 seconds. Furthermore, excellent heating characteristics were maintained even under mechanically deforming environments, exhibiting outstanding flexibility with less than a 3% increase in electrical resistance observed in repetitive bending tests (10,000 cycles, based on a curvature radius of 5 mm). This demonstrates that polyurethane/Ag planar heating structure bears promising potential as a flexible/wearable heating element for curved-shaped appliances and objects subjected to diverse stresses such as human body parts.