• Computers and Concrete
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• 제24권3호
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• pp.223-236
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• 2019

Experience of previous earthquakes shows that a considerable portion of concrete precast buildings sustain relatively large damages especially at the beam-column joints where the damages are mostly caused by bar slippage. Precast concrete buildings have a kind of discontinuity in their beam-column joints, so reinforcement details in this area is too important and have a significant effect on the seismic behavior of these structures. In this study, a relatively simple and efficient nonlinear model is proposed to simulate pre- and post-elastic behavior of the joints in usual practice of precast concrete building. In this model, beam and column components are represented by linear elastic elements, dimensions of the joint panel are defined by rigid elements, and effect of slip is taken into account by a nonlinear rotational spring at the end of the beam. The proposed method is validated by experimental results for both internal and external joints. In addition, the seismic behavior of the precast building damaged during Bojnord earthquake 13 May 2017, is investigated by using the proposed model for the beam-column joints. Damage unexpectedly inducing the precast building in the moderate Bojnord earthquake may confirm that bearing capacity of the precast building was underestimated without consideration of joint behavior effect.

• 지역사회간호학회지
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• 제30권2호
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• pp.243-255
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• 2019

Purpose: The purpose of this study is to examine effects of a multifactorial program for preventing the frailty of older adults and effects of a follow-up program applying a capacity building strategy. Methods: A quasi-experimental pretest-posttest design was used for the nonequivalent control group. The follow-up group (n=75) and non-follow-up group (n=68) received the same multifactorial program comprising muscle strength exercise, cognitive training, and psychosocial programs for 12 weeks. After completion of multifactorial program, the follow-up group took follow-up programs applying the capacity building strategy for following 12 weeks. The data of physical function, cognitive function, and psychological function, and self-rated health were collected from both groups three times: before intervention, after intervention, and 12 weeks after intervention. The data were analyzed using $x^2$ test and t-test. Results: In comparison with the non-follow-up group, the scores of Timed Up & Go Test, and physical activities energy expenditure were significantly improved in the follow-up group. Conclusion: These results indicate that a multifactorial program with follow-up adapting the strategies of capacity building for the older adults group is feasible to prevent the physical frailty in community.

• 환경위생공학
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• 제21권2호
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• pp.11-19
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• 2006

Ran numerical analysis about simplicity warm current model (simple turbulence model) to examine closely distributed laying stress on NOx of contaminant that happen in downtown that building is massed and result is as following. Downtown building is massed and transfer of vehicles can know that frequent area receives greatly effect of building. Pollution displays class kind phenomenon striking in the building, class kind done pollution that show high density being mixed with pollution that happen in vehicles being flowed in again side know can. Divide velocity vector of pollution and density change to ancient city and did numerical analysis. Because NOx is flowed in diversion of water neighborhood by continuous this kind in Godo 20m point, density showed density of $0.0907mg/m^3s$, and can know that Banryuhyeon that Pollution strikes in the building at ancient city 30m point is decreased and approaches with freedom flowing without cooperation (cavity) phenomenon remarkably. Because pollution strikes in the building at distance shaft 383m point, class kind do phenomenon that know appeared notedly Nopeungeonmulgwanat between building pollution density $0.067mg/m^3$ head of a families high appear.

• 건축역사연구
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• 제28권3호
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• pp.55-66
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• 2019

Pinson Hall is a dormitory building of Chosen Christian College, built in 1922, and it still remains comparatively well preserved as original form. This building is worthy in that it shows the living space of western style college in Korea, as well as characteristics of collegiate gothic style and building technology, designed by western architect in 1920s. At first, based on literate review and field survey, this study aims to trace the construction background and process of Pinson Hall, and find out its architectural characteristics with the original form when it is used as dormitory. Additionally, it deals with historic meaning and value of Pinson Hall as a modern western style college dormitory, through comparison with other dormitories in the same era. In conclusion, Pinson Hall is a Western style dormitory which allows students to accustom themselves to Western life style, using bed and desk, as well as it shows the new building technology in the early 1920s which has mixture of masonry and reinforced concrete structure.

• 국제학술발표논문집
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• The 1th International Conference on Construction Engineering and Project Management
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• pp.527-532
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• 2005

The construction industries are facing problems of productivity, quality of work, safety, and the completion of projects in time. In construction industry a worker is exposed to hazardous environment, and has to do more physical work, effecting his health and also productivity. The automation and robotics can offer solution to many problems of the industry. In the past the major barrier to construction automation is the lack of electronic components and systems. This is solved now with the development of information technology, and the current obstacle is the high cost of automated systems, shortage of public money for R&D, and problems of acceptance. The robots employed in construction have followed the same concept as those employed in manufacturing. However, construction industry requires a different kind of robot compared to manufacturing Industry. The robots are stationery and product moves along the assembly line in manufacturing sector, but construction robots have to move about the site because buildings are stationary and of large size. The construction robots must function in adverse weather conditions, including variation in humidity, and temperature and increase the overall construction productivity rate. The major objective of the paper is to review the existing applications of building robots and to assess their implementation in building industry. A case study is considered for the implementation of robots for the painting work of the University Building at Saifabad PG College of Science, Hyderabad, India.

• 국제학술발표논문집
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• The 7th International Conference on Construction Engineering and Project Management Summit Forum on Sustainable Construction and Management
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• pp.159-166
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• 2017

Recently, the wooden structure has been revived again as an eco-friendly structure technique. It is the counterattack of the wood material, which has become more recognized as a finishing material pushed by the concrete material in the rapid growth after the Industrial Revolution. However, it is difficult to conclude that this is a tendency of the construction market in the whole country. Perhaps this is a tendency to appear more strongly in Korea. It could be seen by comparing the characteristics of the overseas construction market with Korean's and the advanced constructed case of large-scale wooden structures in overseas. National wooden buildings show own characteristics such as construction methods, materials, and member dimensions of wood structures by country, which could be seen as a result of continuously developing their own technology. However, in Korea, despite its unique wooden structure and technology (Hanok; Korean traditional housing), it has not been developed continuously and treated it only as a living building exhibit. This is evidenced by the fact that only one percent of the building is constructed with traditional wooden building technology. Therefore, there are various efforts to modernize the traditional wooden structure technology, but it still does not reach the level of advanced wooden technology abroad. The characteristics of the Korean wooden building market were analyzed in order to suggest ways to develop the Korean wood structure technology. The characteristics of Hanok construction were analyzed through quantitative criteria to define the main development tasks for Hanok development to propose the long-term development path.

• 한국CDE학회논문집
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• 제21권1호
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• pp.31-41
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• 2016

Building Information Modeling (BIM) has been adopted in variety domain of construction industry. In this circumstances, interest of BIM model quality has been increased. In many countries, automated building code checking system by Industry Foundation Classes (IFC) has been developed and studied to use web based building permission systems. IFC is international standard of BIM format. However, the data structure of IFC does not include all of objects and properties about national building codes. In this paper, we developed the information specification between IFC data structure and national building code to increase interoperability. First, we drew the criteria from literature review to analyze the building code. And then, we analyzed building code and sorted objects and properties for automated building code checking. After that we made mapping table between the sorted data and IFC specification. Using the mapping table, we developed pre-specification about building codes information that does not exist in IFC specification. And the defined information can be used to develop the BIM modeling guide and national building permission system. The pre-specification support increasing the interoperability between user and automated building code checking system. Increasing thee interoperability makes improvement accuracy and reliability about result of automated building code checking.

• Toxicological Research
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• 제25권4호
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• pp.209-216
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• 2009

We have recently reported that the continuous exposure of rats to a concrete building environment under cool temperatures had adverse effects on general health parameters and embryo-fetal development. This study examined to compare the potential effects of concrete and wood building environments on pregnant dams and embryo-fetal development in rats. Groups of 10 mated females were exposed to polycarbonate (control), concrete, or wood cages from gestational days (GD) 0 to 20 under cool temperatures $(11.9\sim12.3^{\circ}C)$. All the females underwent a caesarean section on GD 20, and their fetuses were examined for any morphological abnormalities. The temperatures in the cages were similar in all groups but the relative humidity in the concrete and wood groups were higher than in the control group. The concentration of volatile organic compounds in the wood group was higher than in the control group. In the concrete group, maternal effects manifested as an increase in the incidence of clinical signs, a lower body weight, and a decrease in the thymus and ovary weights. Developmental effects included increased post-implantation loss and decreased litter size. Infrared thermal analysis showed that the skin temperature of the rats in the concrete group was lower than that in the control group. In contrast, there were no exposure-related adverse effects on the maternal and developmental parameters in the wood group. Overall, the exposure of pregnant rats to a concrete building environment under cool temperatures has adverse effects on the clinical signs, body weight, skin temperature, organ weight, and embryo-fetal development. On the other hand, exposure to a wood building environment does not have any adverse effects in rats.

• Smart Structures and Systems
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• 제26권6호
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• pp.693-701
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• 2020

The conventional Kalman Filter (KF) provides a promising way for structural state estimation. However, the physical parameters of structural systems or models should be available for the estimation. Moreover, it is not applicable when the loadings applied to the structures are unknown. To circumvent the aforementioned limitations, a two-stage KF with unknown input approach is proposed for the simultaneous identification of structural parameters and unknown loadings. In stage 1, a modified observation equation is employed. The structural state vector is estimated by KF on the basis of structural parameters identified at the previous time-step. Then, the unknown input is identified by Least Squares Estimation (LSE). In stage 2, based on the concept of sensitivity matrix, the structural parameters are updated at the current time-step by using the estimated structural states obtained from stage 1. The effectiveness of the proposed approach is numerically validated via a five-story shearing model under random and earthquake excitations. Shaking table tests on a five-story structure are also employed to demonstrate the performance of the proposed approach. It is demonstrated from numerical and experimental results that the proposed approach can be used for the identification of parameters of structure and the external force applied to it with acceptable accuracy.

• KIEAE Journal
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• 제16권4호
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• pp.21-30
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• 2016

Purpose: Energy saving in the built facilities is getting important due to energy crisis. The Korea government has been implemented several energy and green building policies and practices. The both of government and industry also developed green building strategies ant technologies to reduce energy consumption and carbon emission. The purpose of this research is to identify applicable green building strategies and technologies for that can be cost effective and applicable to a multiplex house. Method: This research identified appropriate green building strategies from analysing green building strategies from G-SEED certified apartment projects and popular green building strategies. This study also adopted a survey research method to find out the applicable green building strategies for a multiplex housing. In addition, this research also conduct cost estimating to identify initial cost premium of green building strategies. Results: The research outcomes in this study guide a building owner to know about initial cost premiums of green building strategies and technologies and an architect and contractor to identify appropriate and cost effective green building strategies that can be applicable to a multiplex house.