• Structural Engineering and Mechanics
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• v.77 no.1
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• pp.75-87
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• 2021

The present study pertains to the introduction of two new types of grip adaptor for universal testing machines, namely Polyvinyl Chloride (PVC) and Polyoxymethylene (POM) grip adaptors, and their application to tension testing of FRP bars with different fiber and surface finish types. The tabs are connected to the FRP bar sample with the help of mechanical anchors, i.e. bolts. These new adaptors offer vital superiorities over the existing end tab designs (anchors with filling material or mechanical anchorage), including the reduction in the time and labor for production, reusability and the mild nature, i.e. low hardness of the tab material, which retards and even prevents peeling and crushing in the gripping regions of an FRP sample. The methods were successfully applied to FRP bars with different types of fiber (CFRP, GFRP and BFRP) and different types of surface texture (ribbed, wrapped, sand-coated and wound). The test results indicated that the both types of end caps prevented slip of the bar, crushing and peeling in the gripping zone. The mechanical properties from the material tests with the new caps were in perfect agreement with the ones from the material tests with steel tubular caps.

• Journal of Korea Trade
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• v.26 no.1
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• pp.99-112
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• 2022

Purpose - This paper empirically investigates via a spatial lag model from the perspective of space economy to find the influencing factors of South Korea's OFDI along with 60 countries. Design/methodology - In the study of regional economic phenomena, we must first test the corresponding spatial correlation, and on this basis, complete the construction of the spatial model. For the target research object, after testing the spatial correlation, if there is spatial correlation, a spatial measurement model is needed. This paper uses the global Moran's I index for calculation. Based on the characteristics and research needs of the research object, this paper selects the spatial lag model to verify the existence of the spatial effect and factors affecting OFDI. Findings - Our results show that export scale, infrastructure, technology level, political stability, resource endowment, market size, distance and labor cost have a certain impact on Korea's OFDI, but at present the distance and market size factors are the most important influencing factors for South Korea's OFDI, The technical level and political stability have little effect on South Korea's OFDI, and are not main factors determining South Korea's OFDI. Originality/value - Through spatial measurement verification, it was found that the spatial effect has a significant impact on OFDI, along with more than 60 countries. On this basis, relevant suggestions are put forward, which have strong practical significance for South Korea's OFDI to achieve healthy and sustainable development.

• The Journal of Korea Robotics Society
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• v.17 no.3
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• pp.381-386
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• 2022

We develop a business model for facade cleaning service robot system that provides service by meeting the market needs and environments. The size of the facade cleaning market is growing rapidly in recent years due to the increasing importance of indoor space and the modern trend of building construction methods. Also, maintenance of exterior appearance of buildings has become an important factor in residential and commercial facilities. Though demand for facade cleaning services is rising, the current facade cleaning services are performed dangerously in a human labor-dependent way. It is desirable that the existing human resource service should be replaced with robot-based services. In addition, quantitative analysis of rental pricing model was conducted to propose effective launch of products to the market. The robot system is economically attractive from the consumer's point of view. When the actual facade cleaning robot service is released, it is expected that verification of the business models and more accurate analysis with specific figures can be performed.

• Proceedings of the Korean Society of Computer Information Conference
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• 2021.01a
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• pp.299-300
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• 2021

이른 새벽, 건설업 일용직 근로자들은 '오늘 일을 할 수 있을까?'란 불안감과 COVID-19의 감염 위험을 안고 인력사무소에 출근한다. 새벽 건설업 시장은 높은 업무 강도와 비효율적인 구인/구직 프로세스로 인해 진입장벽이 높고, 건설기능인력의 고령화로 불법체류 근로자 고용 등의 난항을 겪고 있다. 이에 따라 본 연구에서는 건설업 시장의 구인/구직 정보를 제공하여 앱 내에서 근로자 채용을 가능하게 하고, 외부 API를 사용하여 출퇴근 관리, 안전 이수증 촬영을 통한 인증 등 근로자와 구인자를 위한 비대면 구인/구직 앱 '인력거'를 개발하였다. '인력거' 앱을 통해 간소화된 구인/구직 프로세스 등을 통해 건설업에서 청년 일자리 증대가 기대된다.

• Journal of the Korea Safety Management & Science
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• v.26 no.1
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• pp.45-53
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• 2024

A Smart factories are systems that enable quick response to customer demands, reduce defect rates, and maximize productivity. They have evolved from manual labor-intensive processes to automation and now to cyber-physical systems with the help of information and communication technology. However, many small and medium-sized enterprises (SMEs) are still unable to implement even the initial stages of smart factories due to various environmental and economic constraints. Additionally, there is a lack of awareness and understanding of the concept of smart factories. To address this issue, the Cooperation-based Smart Factory Construction Support Project was launched. This project is a differentiated support project that provides customized programs based on the size and level of the company. Research has been conducted to analyze the impact of this project on participating and non-participating companies. The study aims to determine the effectiveness of the support policy and suggest efficient measures for improvement. Furthermore, the research aims to provide direction for future support projects to enhance the manufacturing competitiveness of SMEs. Ultimately, the goal is to improve the overall manufacturing industry and drive innovation.

• Journal of the Korea institute for structural maintenance and inspection
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• v.11 no.6
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• pp.103-112
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• 2007

The purpose of this study is to evaluate the characteristics of the structural behavior in precast segmental prestressed concrete girders, which consist of five precast segments. These girders were developed to save labor and cost in construction field reducing a term of work. Therefore, four different types of specimens of 25m in length were built, and they were tested and analyzed for observing flexural behavior. The analysis included the investigation of the flexural behaviors in varying tendon amount and at joints using the relationship between moment and deflection. Moreover, nonlinear finite element analysis was utilized to verify the experimental result.

• Korean Journal of Construction Engineering and Management
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• v.17 no.2
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• pp.135-145
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• 2016

In Korea, a series of noise-reduced aluminum forms are being recently used in apartment housing construction. However, their complicated and time-consuming work processes, and the noise which is still generated due to the inherent property of aluminum when especially installing and dismantling them have been pointed out as a problem to be certainly solved for increasing their practical use in construction sites. The primary objectives of this study are proposing an optimal conceptual design of a newly designed noise-reduced aluminum form and verifying the technical feasibility by conducting a working mock-up drive experiment. Thus, conventional noise-reduced aluminum forms have been analyzed and three conceptual designs of a newly noise-reduced aluminum forms have been deducted. AHP has been applied to a survey data collected by interviewing field experts. A trade-off analysis results have shown that 'Noise-reduced System Aluminum Form with a Drop-down Floor Post and Adaptive Beam' the highest weights of safety(0.52), work convenience(0.54) and thus selected. The suggested conceptual design in this study improved problems of conventional system aluminum forms. It is also expected that the suggested design will be used as a reliable guideline for the actual development of an aluminum form that ensures noise-reduce, work convenience and labor safety.

• Proceedings of the Korean Institute Of Construction Engineering and Management
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• 2004.11a
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• pp.79-86
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• 2004

The technical expert standing system of our const겨ction industry is operated by the Ministry of Labor subjective national technical qualification law, as the professional engineer, architect and architect-engineer and so on. The construction management(CM) which is introduced on middle 1990 activates a building industry the condition of the essential indispensability for is becoming, is not officially recognized with national qualification to be, that as pending issue it is most urgent, the specialty manpower positivity which is judged as the nostril poop]e for qualification of the civil CM educational institutions has the certification which is a each educational program and a separate way and it is the actual condition which is become accomplished. The problem when as international certification the CMAA which is only it secures a reliability certification which is a CCM and SAVE seeing in the certified which is a CVS, compares in the foreign nation and the CM certification is excessive, it does not secure a reliability and an efficient characteristic to give a confusion to the capital increase lattices which in a condition are, it is mass produced it is a point. It saw from, it observes the capital increase reserve problem point which is a domestic CM and the certification integration which is a report and system anger it leads and with national certified qualification it develops to present the improvement program for, it does to sleep.

• Journal of Korean Society of Occupational and Environmental Hygiene
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• v.17 no.3
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• pp.245-253
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• 2007

This research was performed to evaluate the airborne personal concentration of hazardouse materials during the process of ship construction and surveyed from May 23 to June 30, 2007 in Kyungnam West Distirct, Korea. The subject was 94 ship construction workers exposed to welding fume and respirable particulate. The airborne concentrations of those were compared to Permissible Exposure Limit(PEL) from the Ministry of Labor in Korea. The airborne concentration of 23 samples(48.9%) of welding fumes was less than $5mg/m^3$, that of 16 (34.0%) was between 5 and $10mg/m^3$, and that of 8 (17.0%) was greater than $10mg/m^3$. The airborne concentration of 27 (57.4%) of respirable particulate masses was less than $5mg/m^3$ and the othere are greater than $5mg/m^3$. The welding fumes were identified containing the heavy metasl such as Fe, Mn, Zn, Mg, Ca, and Cu. The respirable particulates has similiar tendency with welding fumes in the component of heavy metals. But the concentration of Ca, Cu, Cr, and Ni turned out to be higher in welding fumes. Twenty (42.6%) of the 47 samples of welding fumes were exceeded PEL. In the heavy metals in welding fumes, ten (21.3%) of the 47 samples of Mn were exceeded PEL. Based on the results, the higher airborne hazardous materials were still exposed to wokers in ship construction process. It is suggested that the appropriate engineering control be applied to minimize the exposed cocnetration in ship building processes.

• Korean Journal of Construction Engineering and Management
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• v.13 no.1
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• pp.118-128
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• 2012

As the bearing wall structure, which has been widely applied to domestic apartment buildings since the 1980s, cause many problems during remodeling of buildings, the government encourages constructors to adopt flat plate or rahmen structure through legal incentives. In line with such a trend, the green frame, an eco-friendly rahmen structure that has removed the shortcomings of previous structures, was developed to enhance structural safety, constructability, and eco-friendliness. The construction of green frame can reduce the labor cost and facilitate the composition of iron bars to reduce rebar loss through calculating the quality and establishing the bar bending schedule automatically on the precast concrete member data collected over the design phase. Therefore, the purpose of this study is to develop the algorithm to automate the calculation of iron bar volume for the green frame designed on composite precast concrete members. Automated algorithm to calculate concrete structural design information and design information. Practices through the application site should prove efficacy. The database established by the developed algorithm will automate the establishment of iron bar processing map and bar cutting list and the calculation of optimal composition and order volume to minimize the rebar loss. This will also reduce the expenses on management staff and overall construction cost through the minimization of rebar loss.